MOLECULAR EXPRESSIONS - Key Persons
The principal Abbe Diffraction Apparatus components are illustrated in the figure presented above. Objective stops are designed to control the amount of light passing through the microscope. The smaller stops on the left transmit only the central beam (smallest single slit) or the central beam and half of the first-order spectra (largest single slit). The stop having three slits is designed to transmit the central beam and the second-order spectra only. The larger stops (on the right-hand side of the drawing) are designed for diffraction experiments with a 10x achromatic objective. An inexpensive kit, the equipment was proposed by Ernst Abbe in 1876 and manufactured for many years by the Carl Zeiss Company for their 6x achromatic objective having a numerical aperture of 0.17. The 10x objective stops are an aftermarket product designed to be used with the more widely available higher magnification lenses.
Albert Michelson (1852-1931) - Albert Abraham Michelson, a Polish-American physicist, was awarded the Nobel Prize in Physics in 1907. He is best known for his experiments in which he proved that the hypothetical medium of light, the "ether", did not exist, and his many attempts at accurately measuring the speed of light. Michelson is also well known for developing a means to more accurately measure the speed of light and the size of stars.
Albertus Magnus (1193-1280) - During his pursuit of science, Albertus touched upon a number of subjects and phenomena, including the nature of light. He was particularly interested in the formation of rainbows and wrote upon the subject with enthusiasm. He also hypothesized that the speed of light was finite though it could travel extremely fast, and examined the darkening action of bright sunlight on crystals of silver nitrate. Furthermore, looking out at the night sky, Albertus determined that the Milky Way was just an immense assembly of stars that received the light of the sun and argued that figures visible on the face of the moon were configurations on its surface, rather than a reflection of the Earth's seas and mountains, as had been previously believed. He also studied the reflection of light through the use mirrors, as well as the refraction capabilities of certain crystals.
Alexander Jablonski (1898-1980) - Born in the Ukraine in 1898, Alexander Jablonski is best known as the father of fluorescence spectroscopy. Jablonski's primary scientific interest was the polarization of photoluminescence in solutions, and in order to explain experimental evidence gained in the field, he differentiated the transition moments between absorption and emission. His work resulted in his introduction of what is now known as a Jablonski Energy Diagram, a tool that can be used to explain the kinetics and spectra of fluorescence, phosphorescence, and delayed fluorescence.
Alexandre Edmond Becquerel (1820-1891) - During his investigations into the nature of fluorescence and phosphorescence, Becquerel invented the phosphoroscope, a device capable of measuring the duration of time between the exposure of a solid, liquid, or gas to a light source and the substance's exhibition of phosphorescence. Through the use of the phosphoroscope, the physicist was able to more accurately determine whether or not certain materials exhibited phosphorescence or fluorescence. The phosphoroscope also enabled Becquerel to discover phosphorescence in a number of materials that were previously not believed to exhibit the effect.
Anders Jöns Ångström (1814-1874) - Anders Ångström was a Swedish physicist, mathematician, and astronomer who is widely considered the father of spectroscopy. In his research, Ångström expressed the results in the unit (one ten-millionth of a millimeter) that now bears his name.
Angelo Sala (1576-1637) - Angelo Sala was the self-educated son of an Italian spinner whose experiments with silver salts were an important step towards the invention of the photographic process. In 1614, he demonstrated that the sun blackened powdered silver nitrate, as well as paper that was wrapped around it, and published his findings in a pamphlet. Robert Boyle had made a similar observation previously, but mistakenly believed that the darkening resulted from exposure to air, rather than light. It was not until Sala's discovery was combined with the optics work of many others, however, that photography was finally invented in the 1830s.
Antonie van Leeuwenhoek (1632-1723) - Antonie van Leeuwenhoek was a famous Dutch scientist who made simple microscopes that were able to magnify objects over 275 times, an amazing feat for the period. He studied Protists, plant cells, various types of algae, and was the first person to view bacteria, which he termed "animalcules". Leeuwenhoek's curiosity about this microscopic world and his diligence in recording his painstaking observations enabled him to share with others what he had seen with his microscopes.
Armand Fizeau (1819-1896) - Armand Fizeau is best known for being the first to develop a reliable experimental method of determining the speed of light on the Earth. Previously, the speed of light was measured based upon astronomical phenomena. Fizeau also conducted experiments that demonstrated that the velocity of light is a constant, regardless of the motion of the medium it is passing through. It was previously established that light traveled at different rates through different mediums, but prior to Fizeau's discovery, it was believed that if the medium was in motion, the velocity of the speed of light would be increased by the movement of the medium.
August Köhler (1866-1948) - August Köhler, a German scientist and expert microscopist born in 1866, is best known for his development of a superior microscope illumination technique, which is still utilized today, and for designing the first ultraviolet microscope. The method, termed Köhler illumination, is also known as double diaphragm illumination, because it uses both a field and an aperture iris diaphragm to configure microscope illumination. Setting up the light path correctly with this configuration results in an evenly illuminated field of view and a brighter image without glare.
Becke Lines - Are defined as the broad, dark or bright lines (due to refraction and/or diffraction) formed in the image at the boundary between media of different optical path lengths. They move in the direction of the longer optical path when the distance between the objective and the object is increased. The Becke line disappears in the region of the object that lies in exact focus.
Formation of Becke lines is illustrated in the figure above. In (a) the transparent specimen has a higher refractive index than the surrounding medium. When the objective is raised above focus a bright Becke line appears inside the specimen, but the Becke line appears to enlarge and surrounds the specimen when the objective is moved below the focus point. If the specimen has a lower refractive index than that of the medium (b), the situation is reversed and raising the objective above focus produces a bright Becke line surrounding the specimen.
Grains and fibers are often convex in shape and either diverge or converge light, depending upon whether their refractive index is lower or higher than the surrounding medium (usually oil). In either case, light is converged into the medium having a higher refractive index. A specimen having parallel faces will produce Becke lines at the boundaries having the higher refractive index by total internal reflection.
Reliable Becke lines may be obtained with medium-power objectives (10x through 50x) with numerical apertures ranging from 0.5 to around 0.7. The condenser aperture should be reduced until strong Becke lines are observed through the microscope eyepieces, with increasingly smaller aperture sizes being employed as the refractive index difference between the specimen and medium is narrowed. Adjustment of the condenser aperture should be undertaken while viewing the specimen and progressively closing the diaphragm until good Becke lines are observed.
Note: This phenomenon is used to recognize relative differences in refractive index of two adjacent media, for example, a particle and the surrounding mounting medium. When the refractive indices are matched the Becke line disappears.
Benjamin Franklin (1706-1790) - Benjamin Franklin was born to a poor soap boiler on January 17, 1706 in Boston, Massachusetts. As a journalist, scientist, inventor, statesmen, philosopher, musician, and economist, Benjamin Franklin can be thought of as a colonial Renaissance man. Through hard work and great ideas, Franklin helped shaped a young nation with the aid of his many hard-earned skills. Benjamin Franklin was a pivotal player in the foundation of the United States of America.
Benjamin Martin (1704-1782) - Benjamin Martin, an eighteenth century English instrument maker, is considered one the greatest designers and manufacturers of microscopes of his time. Martin had a significant influence on the development of the microscope and optical instruments in general, and designed several microscopes that were revolutionary for the period. He was one of the first designers to incorporate achromatic lenses into microscopes to help reduce the severity of chromatic aberration.
Carl Zeiss (1816-1888) - Carl Zeiss was a famous German instrument maker who lived during the nineteenth century and founded Carl Zeiss, Inc., one of the world's leading manufacturers of optical microscopes and related equipment. Zeiss was also instrumental in the foundation of the Schott Glass Works through a collaboration with Ernst Abbe and Otto Schott. Today, Zeiss microscopes are renowned for their high optical quality and fine craftsmanship.
Chandrasekhar Venkata Raman (1888-1970) - While studying light diffraction, Raman discovered that when an intense light was passed through a transparent medium, a small fraction of the light surfaced in directions other than the incoming beam, and an even smaller part of this fraction of light exhibited different wavelengths than the incident light. After his findings were made public in 1928, the scattering of the light molecules came to be known as Raman scattering, which was considered a result of the Raman effect, the change in wavelength of light when it is deflected by molecules.
Charles Wheatstone (1802-1875) - Charles Wheatstone was a prominent nineteenth century physicist who made significant contributions to a number of areas without having ever received a formal scientific education. He was particularly influential in the field of optics where he revolutionized contemporary notions of vision and spatial perception. His various studies and experiments led Wheatstone to develop the theory of stereoscopic vision, which involves the idea that each eye sees a slightly different view of a single scene, which combine in a way that results in depth perception. In addition to his work in optics, Wheatstone also designed the first viable telegraph system in conjunction with William Cooke, and measured the velocity of current flow. His other significant contributions in the field of electricity include improvements to the dynamo, the invention of an adjustable resistor known as the rheostat, and popularizing a method of measuring electrical resistance invented by Samuel Christie, which came to be known as the Wheatstone bridge.
Christiaan Huygens (1629-1695) - Christiaan Huygens was a brilliant Dutch mathematician, physicist, and astronomer who lived during the seventeenth century, a period sometimes referred to as the Scientific Revolution. Huygens, a particularly gifted scientist, is best known for his work on the theories of centrifugal force, the wave theory of light, and the pendulum clock. His theories neatly explained the laws of refraction, diffraction, interference, and reflection, and Huygens went on to make major advances in the theories concerning the phenomena of double refraction (birefringence) and polarization of light.
Christian Doppler (1803-1853) - Christian Johann Doppler was a nineteenth century physicist and mathematician who is most often remembered for his discovery of the Doppler effect, which is central to modern conceptions of sound and light. Doppler first demonstrated this phenomenon with a group of musicians traveling in an open railroad car, but was unable to successfully prove the theory for visible light frequencies. Since that time, however, the Doppler effect has proven invaluable for astronomical observations, paving the way for a host of new scientific discoveries and concepts. Most notably, the motions of stars detected through this manner led to the development of the big bang theory of creation.
Claude Chappe (1763-1805) - Claude Chappe was an engineer and cleric who invented a device known as the semaphore visual telegraph, an optical signaling system especially important during the French Revolution. In August of 1794, Chappe's semaphore visual telegraph conveyed in less than an hour the news that the Republican army had recaptured Condé-sur-l'Escaut from the Austrians, a feat that would have taken approximately twenty-four hours if transported by courier on horseback. The system was considered a success and another line was soon installed between Paris and Landau, others following in later years.
Claudius Ptolemy (Approximately 87-150) - Claudius Ptolemy was one of the most influential Greek astronomers and geographers of his time. Ptolemy propounded the geocentric theory in a form that prevailed for 1400 years. According to historians, Ptolemy was a mathematician of the very highest rank, however others believed that he committed a crime against his fellow scientists by betraying the ethics and integrity of his profession.
Colonel Billings received the first shipment of 17 microscopes from Mayall in October 1884, followed by eight very rare microscopes in 1886, and three early Italian models in 1887. By 1888, Mayall had purchased over 140 microscopes for Colonel Billings, who was himself searching throughout Europe for antique instruments. These efforts inspired many American collectors to contribute to the growing museum collection and Colonel Billings continued to assist in growing the collection until his death in 1913.
Today, the collection houses over 600 microscopes, many of which are very rare and valuable. Army museum curators have now termed these microscopes The Billings Microscope Collection, and a book has been written that illustrates and describes the microscopes.
Daniel Barbaro (1514-1570) - Daniel Barbaro was an Italian nobleman who encouraged the use of the camera obscura for artistic endeavors. By the time he adapted the technique, however, the chamber of the camera obscura was typically a simple box rather than an entire room. Barbaro is credited with translating ten books on architecture written by the celebrated Roman engineer Vitruvius and composed his own work "La pratica della perspettiva" ("Practice of Perspective"), which was published in 1568.
Dennis Gabor (1900-1979) - In the late 1940s, Dennis Gabor attempted to improve the resolution of the electron microscope using a procedure that he called wavefront reconstruction, but which is now known as holography. Though he was unable to realize his goal at the time, his work was to find much more prolific use years later, after the development of the laser in 1960. Gabor received the Nobel Prize in Physics in 1971 for his foundational holographic research and experimentation.
Galileo Galilei (1564-1642) - Galileo's many and varied accomplishments span the scientific disciplines of astronomy, physics, and optics. He was also an inventor, mathematician, and author who is widely known for his famous experiment dropping different size balls from the Leaning Tower of Pisa that resulted in new ideas about physics and the idea that "laws" of science could, and should, be questioned.
Robert Grosseteste (1175-1253) - Grosseteste was particularly interested in astronomy and mathematics, and he asserted that the latter was essential to investigations of natural phenomena. Consequently, his study of light often took a mathematical turn, resulting in a refinement of optical science. In his investigations of rainbows, comets, and other optical phenomena, he notably made use of both observational data and mathematical formulations. Moreover, Grosseteste was an early proponent of the need for experimental support of scientific theories and carried out numerous experiments with mirrors and lenses.
Edmund Halley (1656-1742) - Though they at first appeared to follow different laws of motion than the planets, Edmund Halley believed that comets must also be affected by gravitational pulls. In his analysis of comet observations, he realized that certain aspects of three were so similar that they must be the successive returns of a single entity whose orbit was an elongated ellipse. He then determined the periodicity of the comet and successfully predicted it would return in 1758. In addition to his study of comets, Halley discovered relative motion among the stars, which had previously been believed to be fixed. He contrived the first meteorological weather map and established accurate quantitative mortality tables. Halley also commanded the first sea voyage undertaken purely for scientific purposes, noting any compass variations that could be caused by the Earth's magnetic field.
Edmund Hartnack (1826-1891) - Edmund Hartnack was a nineteenth century German microscope maker who studied his craft in Berlin under Wilhelm Hirschmann. In 1857, Hartnack joined the instrument-making firm of his uncle, Georges Oberhauser (1798-1868), which was based in Paris and enjoyed a reputation for high quality products. Hartnack made improvements to the drum-shaped microscope that allowed for better and more easily obtained oblique lighting and was also one of the first instrument makers to include a substage condenser in his designs. Hartnack is perhaps best known, however, for the great improvements he made to water immersion lenses.
Job Titles:
- Founder of the Polaroid Corporation
Edwin Herbert Land (1909-1991) - The founder of the Polaroid Corporation, Edwin Herbert Land was an American inventor and researcher who dedicated his entire adult life to the study of polarized light, photography and color vision. Perhaps Land's most famous contribution to science, however, was his development of instant photography. The invention was inspired by his three-year old daughter when she asked him why she could not instantly see a picture he had just taken of her on vacation. The one-step dry photographic process took Land three years to perfect, but his success was phenomenal.
Ernest Rutherford (1871-1937) - Rutherford's atomic model paved the way for the modern understanding of the atom. It was also the foundation of the important developments regarding the structure of atoms made by Niels Bohr, who was once his protégée. Based on studies of alpha particles passing through thin plates of mica and gold, Rutherford came to the conclusion that the intense electric field required to cause the large deflections that were occurring could be explained only if all the positive charge in the atom were concentrated on a very small central nucleus. He further postulated that the positive charge on the nucleus must be balanced by an equal charge on all the electrons distributed around the nucleus.
Ernst Abbe (1840-1905) - Ernst Abbe was a brilliant German mathematician and physicist who made several of the most important contributions to the design of lenses for optical microscopy. Abbe studied physics and mathematics as an undergraduate at the University of Jena and went to graduate school at the University of Göttingen, where he received a doctorate in thermodynamics. In 1863 Abbe joined the faculty at the University of Jena where he taught physics. He met Carl Zeiss in 1866 and became very interested in the optical problems surrounding mid-nineteenth century microscopy. Together with Zeiss, Abbe formed a partnership and he was made the research director of Zeiss Optical Works late in 1866, and assumed control of the company when Zeiss died in 1888.
Ernst Abbe was a brilliant German mathematician and physicist who made several of the most important contributions to the design of lenses for optical microscopy. As a young boy, Abbe lived in an impoverished family where his father labored 16 hours a day to provide for his wife and children. Abbe worked his way through school by earning scholarships and with the help of his father's employer.
Abbe studied physics and mathematics as an undergraduate at the University of Jena and went to graduate school at the University of Göttingen, where he received a doctorate in thermodynamics. In 1863 Abbe joined the faculty at the University of Jena where he taught physics. He met Carl Zeiss in 1866 and became very interested in the optical problems surrounding mid-nineteenth century microscopy.
Together with Zeiss, Abbe formed a partnership and he was made the research director of Zeiss Optical Works late in 1866. For the next six years, Zeiss and Abbe worked intensively to lay the scientific foundations for the design and fabrication of advanced optical systems. In 1869, they introduced a new "illumination apparatus" that was designed to improve the performance of microscope illumination. Three years later, in 1872, Abbe formulated his wave theory of microscopic imaging and defined what would become known as the "Abbe Sine Condition". Several years later, Zeiss began to offer a lineup of 17 microscope objectives designed on the basis of Abbe's theoretical calculations. In his own words Abbe stated:
Ernst Ruska (1906-1988) - German engineer Ernst Ruska designed and built the first electron microscope, a device that far surpassed previous resolution capabilities and allowed scientists to view things too small to be seen with a light microscope. He was awarded the Nobel Prize for Physics in 1986 for the feat, an honor he shared that year with Heinrich Rohrer and Gerd Binnig, who co-developed the scanning tunneling microscope.
Erwin Müller (1911-1977) - Erwin Wilhelm Müller was a German-born physicist who invented both the field emission microscope and the field ion microscope, the latter of which enabled him to be the first person to ever observe individual atoms. In 1967, Müller invented yet another important scientific instrument, which he referred to as an atom probe, but later came to be more widely known as the atom probe field ion microscope. Along with Müller's other inventions, the atom probe field ion microscope represented a significant advance in the field of materials science.
Erwin Schrödinger (1887-1961) - The Austrian physicist Erwin Schrödinger made fundamental advances in establishing the groundwork of the wave mechanics approach to quantum theory. Influenced by de Broglie's work, which had gained additional weight due to the support of Albert Einstein, Schrödinger attributed the quantum energies of the electron orbits in the atom thought to exist to the vibration frequencies of electron matter waves, now known as de Broglie waves, around the nucleus of the atom. For his significant contributions to science, Schrödinger was bestowed with many honors, including the Nobel Prize for Physics, which he shared with Paul Dirac in 1933.
Friedrich Johann Karl Becke (1855-1931) - Friedrich Johann Karl Becke was an Austrian geologist, mineralogist and petrologist from the University of Prague, who developed a method for determining the relationship between light refraction and refractive index differences observed in microscopic specimens. The phenomenon, which is now referred to as the formation of Becke lines, has been named for him.
Friedrich Johann Karl Becke was an Austrian geologist, mineralogist and petrologist from the University of Prague, who developed a method for determining the relationship between light refraction and refractive index differences observed in microscopic specimens. The phenomenon, which is now referred to as the formation of Becke lines, has been named for him. Becke also conducted important work on metamorphic rock recrystallization, and later contributed to the development of a descriptive terminology and classification of mineral assemblages in metamorphic rocks.
In transmitted-light microscopy, the Becke line test is a comparative test utilized to determine the approximate refractive index of a mineral. Utilizing plane-polarized light, the substage iris diaphragm is partly closed to accentuate grain boundaries, resulting in the appearance of a thin line of light, the Becke line, which either surrounds the specimen or is visible within the specimen boundaries. If the microscope objective is then moved up or down, away from the position of focus, the Becke line will move into the medium having a higher refractive index. In general, a medium suitable for determination of refractive indices (and to observe Becke lines) is either an adjacent mineral of known refractive index, an immersion oil, or a mounting medium such as Canada balsam.
Born on New Year's Eve, 1855 in Prague (then part of the Austro-Hungarian Empire), Becke moved to Vienna, where he studied under Gustav Tschermak and was appointed chairman of mineralogy at the University of Vienna (1898). Many years later, he was made rector (1921), and died ten years after that in the summer of 1931. Becke presented a landmark paper (1903) on the composition and texture of the crystalline schists to the International Geological Congress, which represented the first comprehensive theory on metamorphic rocks. His subsequent work on retrogressive metamorphism led to a more thorough understanding of many ancient mountain belts, and he served as editor of the journal Mineralogische und Petrographische Mitteilungen (Mineralogical and Petrographical Notices) after 1899.
The Austrian Mineralogical Society (founded in 1901) awards the Becke Medal, a tribute to the famous mineralogist and their second president, to outstanding scientists for their significant contributions to mineralogy, crystallography, petrology, and other disciplines in geophysics and geochemistry. Becke was a member of the Berlin-Brandenburg Academy of Sciences and Humanities (then the Prussian Academy of Sciences and Humanities) and an honorary member of the Geological Society of Sweden (1916).
Friedrich Adolf Nobert (1806-1881) - Friedrich Nobert was a German scientist and instrument maker who was the first to develop fine line gratings used in stage micrometers. Nobert attached an apparatus, which held a carefully positioned diamond point, to a circle dividing engine so he could cut parallel ruled sets of lines onto glass. His first test plate, created in 1845, contained ten ruled lines separated by a specific distance. The first line was divided into 1/1000 of a Paris line and the tenth into 1/4000 of a Paris line. In this manner, the first resolution test for the compound optical microscope had been created.
Frits Zernike (1888-1966) - Frits Zernike was a Dutch-born German mathematician and physicist who discovered the phase contrast phenomenon and won a Nobel Prize in 1953. As a young man, Zernike was very interested in physics and chemistry. He accumulated a variety of spare equipment with which he would perform numerous experiments. Zernike was also interested in mathematics, astronomy, and photography, and conducted a number of investigations in these areas. He even dabbled in color photography when the field was largely experimental.
George Eastman (1854-1932) - From humble beginnings, George Eastman revolutionized the field of photography by simplifying the process and making it accessible to the masses. In 1884, he patented a paperbacked-film, and roll-holders to use with the material soon followed. The new photographic system was instantly successful, but Eastman was intent on reaching an even wider consumer base. He was struck with the idea of selling a preloaded camera that was sent back to the company for development and printing, making photography possible even for amateurs. In 1888, the first Kodak camera was ready to be sold and Eastman advertised in the leading periodicals, introducing photography to the general public to much acclaim.
George Gabriel Stokes (1819-1903) - Throughout his career, George Stokes emphasized the importance of experimentation and problem solving, rather than focusing solely on pure mathematics. His practical approach served him well and he made important advances in several fields, most notably hydrodynamics and optics. Stokes coined the term fluorescence, discovered that fluorescence can be induced in certain substances by stimulation with ultraviolet light, and formulated Stokes Law in 1852. Sometimes referred to as Stokes shift, the law holds that the wavelength of fluorescent light is always greater than the wavelength of the exciting light. An advocate of the wave theory of light, Stokes was one of the prominent nineteenth century scientists that believed in the concept of an ether permeating space, which he supposed was necessary for light waves to travel.
Georges Nomarski (1919-1997) - A Polish born physicist and optics theoretician, Georges Nomarski adopted France as his home after World War II. He is credited with numerous inventions and patents, including a major contribution to the well-known differential interference contrast (DIC) microscopy technique. Also referred to as Nomarski interference contrast (NIC), the method is widely used to study live biological specimens and unstained tissues.
Giovanni Battista Amici (1786-1863) - Giovanni Amici was an Italian microscopist, astronomer, optical instrument designer, and botanist, who is best known as the achromatic lens inventor, also designed reflecting telescopes and introduced a lens for the inspection of an objective's rear focal plane, termed the Amici-Bertrand lens. In 1850, he also invented the water immersion lens.
Giovanni Amici was an Italian microscopist, astronomer, optical instrument designer, and botanist, who is best known as the achromatic lens inventor, also designed reflecting telescopes and introduced a lens for the inspection of an objective's rear focal plane, termed the Amici-Bertrand lens. In 1850, he also invented the water immersion lens.
Born in the Duchy of Modena, Amici received an 1807 diploma in engineering and architecture from the University of Bologna. He was a professor of mathematics at the University of Modena (1815-1825) and then chief astronomer to the Grand Duke of Tuscany. Amici was also the director of the observatory and professor of astronomy at Royal Museum in Florence. By 1859, he was responsible for reporting microscopic observations to the Museum of Physics and Natural History where he published a wide variety of papers. Minor planet (3809) Amici is named in his honor, as is a crater on the dark side of the Moon.
In 1840, Amici introduced the oil-immersion technique to microscopy that minimizes optical aberrations, followed by the water-immersion objective (1855). Many innovations by this nineteenth century Italian designer have led important developments in the modern microscope, including a compound "periscope" instrument (1833) that moved microscopic viewing from the horizontal to vertical position, and a series of horizontal compound achromatic microscopes (circa 1850). One achromatic microscope had a quad-observation tube that allowed four individuals to simultaneously observe the specimen. The Amici prism, a combination of three prisms, is still used in refracting spectroscopy.
In astronomy, Amici studied double stars, Jupiter's moons and designed improvements to reflecting telescope mirrors including grinding several 10-inch and 12-inch metal mirrors. With his own micrometer design, Amici made accurate measurements of the polar and equatorial diameters of the Sun. Combining botany interests with innovative advances in compound microscopes, the Italian scientist made important discoveries about the circulation of sap in plants and the processes of plant reproduction, including many details of orchid pollination and seed development.
Giovanni Borelli (1608-1679) - Born as Giovanni Francesco Antonio Alfonso in Naples, Italy on July 28, 1608, the son of a Spanish infantryman was to become a great mathematician and physicist, later changing his surname to Borelli. An adept microscopist, Borelli was dedicated to preserving and advancing the Galilean tradition of studying nature and is most renowned for his studies in physiology. In 1681, Borelli posthumously published a work that ultimately led to his being termed the father of biomechanics. His physiological studies were based on solid mechanical principles, which included muscle analysis and a mathematical illustration of movements, such as running and jumping.
Savile Bradbury (1931-2001) - Savile Bradbury, a noted English microscopist, published his first paper in 1955, and more than 80 more were to follow over the rest of his career. He also authored, or co-authored, 13 books, many of them staples of the scientific community. Through works such as The Evolution of the Microscope (1967), An Introduction to the Optical Microscope (1989), and Introduction to Light Microscopy (1998), Bradbury pioneered efforts to both preserve the history of microscopy and to introduce the field to a new generation of scientists. He was also a talented lecturer, and reached thousands of developing minds through his educational and interesting presentations.
Borelli was a professor of mathematics at Messina beginning in 1649, but took another teaching position in Pisa in 1656. Eleven years later he returned to Messina, but was compelled to retire in 1674 to Rome, where he lived under the protection of Christina, Queen of Sweden. Throughout his lifetime Borelli carefully studied a variety of topics, but he is particularly noted for his microscopic investigations of red blood cells and his accurate observation of the regularity of stomatal movements in plants.
Girolamo Cardano (1501-1576) - Girolamo Cardano was a sixteenth century mathematician and physician who made an important adaptation to the design of the camera obscura. His most popular works during his lifetime were De subtilitate libri, published in 1550, and its follow-up De subtilitate rerum, published in 1557. The works covered a wide array of topics and contained natural history, anecdotes, physical experiments, and inventions. It was in De subtilitate libri that Cardano made his primary contribution to optics. Within the work, he described the use of a bi-convex lens in conjunction with a camera obscura, the earliest known mention of such a design. He also included detailed descriptions of the improved images he was able to achieve with the configuration, which increased both sharpness and intensity.
Gregorio Weber (1916-1997) - At Cambridge University in England, Gregorio Weber's thesis advisor suggested he study the fluorescence of flavins and flavoproteins, instigating the beginning of a long, successful career that resulted in Weber becoming generally recognized as the founder of modern fluorescence spectroscopy. Among the many groundbreaking feats that Weber achieved in the field of fluorescence was the introduction of fluorescence polarization as a method to study macromolecular dynamics, the creation of the first broadly utilized phase-modulation fluorometer, and the presentation of the first report regarding the classical technique of measuring the absolute quantum yield of fluorescence.
Gustav Robert Kirchhoff (1824-1887) - Gustav Kirchhoff was a nineteenth century physicist who is well known for his contributions to circuit theory and the understanding of thermal emission, but who also made significant discoveries in optics. His work in the area spectroscopy, much of which was carried out in conjunction with chemist Robert Bunsen, was foundational to the field, as was his study of black body radiation. Kirchhoff's findings are commonly considered to have been instrumental to Max Planck's quantum theory of electromagnetic radiation formulated at the beginning of the twentieth century.
Hans Lippershey (1570-1619) - Hans Lippershey was a Dutch eyeglass maker who most historians believe was the inventor of the first telescope. In 1608, Lippershey applied for a patent for his telescope with the Belgian government. Lippershey called his invention a kijker, meaning looker in Dutch. Even though he was paid very well for his invention, a patent was not granted because it was felt the instrument could not be kept a secret.
Heinrich Rudolph Hertz (1857-1894) - The German physicist Heinrich Hertz is widely known for his work with electromagnetic waves, but is also important for his contributions to the field of optics. Most notably, Hertz was the first investigator ever to observe the phenomenon that would eventually come to be known as the photoelectric effect. The discovery of this phenomenon, which is generally defined as the emission of electrons from a surface exposed to electromagnetic radiation above a certain threshold frequency, had a tremendous influence on the perception of light, which was just beginning to be understood in terms of a duality between waves and particles late in Hertz's lifetime, and which would not come to be widely accepted until many years after his death.
Henry Baker (1698-1774) - Henry Baker was an eighteenth century English naturalist, poet and pioneer of education for the deaf and for children with speech impediments. Although he did not make any major contributions in the areas of scientific research, he made a significant contribution to the popularization and dissemination of scientific knowledge. His particular interest was the field of microscopy. Baker published two books about microscopes that were widely popular with translations made into Dutch and French.
Hugh Powell (1799-1883) - Hugh Powell was a famous British instrument maker who, together with his brother-in-law Peter Lealand, made the world-renowned No. 1 microscope. Powell was a pioneer of using very high powers in objective lens systems and advanced microscope design, and his contributions to the fields of optics and microscopy were integral in the shaping of modern research. In fact, many of Powell's designs are still incorporated in scientific instruments today.
Ignazio Porro (1801-1875) - Ignazio Porro's primary contribution to optics was an innovative prism image erecting system that is commonly used in binoculars and stereomicroscopes, though he also invented and improved a number of other scientific instruments. Binoculars designed with Porro prisms, which were first conceived in the mid-1800s, were refined by other scientists and became one of the most popular varieties of binoculars by the dawn of twentieth century. In fact, the instruments, which enjoy simplicity of design as well as greater depth perception and a wider field-of-view than many other binocular designs, continue to be sold around the globe in the early twenty-first century.
Jacques Babinet (1794-1872) - Jacques Babinet was a French physicist, mathematician, and astronomer born in Lusignan, who is most famous for his contributions to optics. Among Babinet's accomplishments are the 1827 standardization of the Ångström unit for measuring light using the red cadmium line's wavelength, and the principle (bearing his name) that similar diffraction patterns are produced by two complementary screens.
Jacques Babinet was a French physicist, mathematician, and astronomer born in Lusignan, who is most famous for his contributions to optics. Among Babinet's accomplishments are the 1827 standardization of the Ångström unit for measuring light using the red cadmium line's wavelength, and the principle (bearing his name) that similar diffraction patterns are produced by two complementary screens.
After initiating his studies at the Lycée Napoléon, Babinet was persuaded to abandon his legal education for the pursuit of science. Formally educated at the École Polytechnique, which he left in 1812 for the Military School at Metz, Babinet was later a professor at the Sorbonne and in 1840, elected as a member of the French Academy of Sciences. In addition to his brilliant lectures on meteorology and optics research, Babinet was also a great promoter of science, an amusing and clever lecturer, and a brilliant and entertaining author of popular scientific articles. Unlike many of his contemporaries, Babinet was beloved by all for his kindly and charitable nature.
Babinet was interested in the optical properties of minerals throughout his career. He designed and created many scientific instruments utilized to determine crystalline structure and polarization properties, including the polariscope and a goniometer to measure refractive indices. The Babinet compensator, an accessory useful in polarized light microscopy, was built with twin, opposed quartz wedges having mutually perpendicular crystallographic axes, and is still widely employed in microscopy. This design avoids the problems inherent in the basic quartz wedge, where the zero reading coincides with the thin end of the wedge, which is often lost when grinding the plate during manufacture.
Expanding his fascination of diffraction to meteorology, Babinet spent a significant amount of time in the study of rainbow optics. His astronomical research focused on Mercury's mass and the Earth's magnetism, while his inventions included valve improvements for air pumps and a hygrometer. In geography and hydrogeomorphology, the Baer-Babinet Law helps to explain and predict directionality in the course of rivers. Babinet's cartography work includes homalographic projections where the parallels are rectilinear and meridian lines are elliptical.
Babinet Compensator - An optical device that enables the addition of a controllable retardation to the optical path difference of a specimen in polarized light microscopy. Unlike a fixed wave plate where the path difference is fixed, a Babinet compensator can be adjusted to provide a variable path difference.
The Babinet compensator consists of paired quartz wedges, which are cut in such a fashion that one is positioned with the optical axis parallel to the edge, while the other has the axis perpendicular to the edge. The optical path difference in each wedge increases from the edge to the base and the birefringence has opposite values in the wedges. When combined, a line appears where the net optical path difference through the compensator becomes zero, and increases in a direction at right angles to the zero line as the distance grows larger. Between crossed polarizers, dark bands are observed in monochromatic light at a separation distance of one wavelength of optical path difference. In white light, the polarization colors appear in rising orders. In polarized light microscopy, measurements are conducted by observing the fringe shift caused by the addition of the optical path difference of the specimen under observation.
James Bradley (1693-1762) - James Bradley was an English astronomer most famous for his discovery of the aberration of starlight. The finding was an important piece of evidence supporting Copernicus's theory that the Earth moved around the sun and provided an alternative way to assess the velocity of light. When Edmund Halley died in 1742, Bradley was named his successor as Astronomer Royal at Greenwich Observatory. He held the influential position for the rest of his life, greatly improving upon the condition of the observatory and the instruments it contained.
James Clerk Maxwell (1831-1879) - James Clerk Maxwell was one of the greatest scientists of the nineteenth century. He is best known for the formulation of the theory of electromagnetism and in making the connection between light and electromagnetic waves. He also made significant contributions in the areas of physics, mathematics, astronomy and engineering. He considered by many as the father of modern physics.
James Gregory (1638-1675) - James Gregory was a seventeenth century mathematician and astronomer who developed infinite series representations for various trigonometric functions, but is better known for providing the first account of a practical reflecting telescope. Due to his hesitancy to publish, however, he received only a fraction of the credit he deserved during his lifetime, the magnitude of his achievements only becoming recognized in the 1930s when his papers were examined and published by H. W. Turnbull.
James Hillier (1915-Present) - During his graduate years at the University of Toronto, James Hillier became involved in a project that would alter the course of his life, as well as the field of electron microscopy. As a graduate student, Hillier, along with Albert Prebus developed a high-voltage electron microscope that could be used to examine biological specimens. The device they created could magnify objects up to 7,000 times their actual size, a significant improvement over 1930s light microscopes, which could only increase the dimensions of specimens by about 2000 times.
Jan Jacbz Swammerdam (1637-1680) - Jan Swammerdam was a seventeenth century Dutch microscopist and naturalist who is most famous for his microscopic observations and descriptions of insect development that were published posthumously as The Bible of Nature, but is more often referred to as The Book of Nature due to a mistranslation of the title. Swammerdam pioneered the use of the microscope for zoological purposes, and is considered a founder of both comparative anatomy and entomology.
Jean-Baptiste Biot (1774-1862) - Jean-Baptiste Biot was a physicist and mathematician who made advances in geometry, astronomy, elasticity, magnetism, heat and optics. For his work on the polarization of light passing through chemical solutions, Biot received the Rumford Medal from the Royal Society in 1840. Biot also worked with Felix Savart to discover that the intensity of the magnetic field established by a wire carrying an electric current is inversely proportional to the distance from the wire. The relationship, now referred to as the Biot-Savart Law, is an elemental component of modern electromagnetic theory.
Jean-Baptiste Biot was a physicist and mathematician who made advances in geometry, astronomy, elasticity, magnetism, heat and optics. For his work on the polarization of light passing through chemical solutions, Biot received the Rumford Medal from the Royal Society in 1840.
Biot's father was a treasury official who had planned for his son to enter the world of commerce. Biot was provided with a private math tutor in his youth and was educated at the college of Louis-le-Grand before joining the French army in 1793. After serving briefly in the artillery, he enrolled at the Polytechnic School in Paris. He later moved to Beauvais to act as a mathematics professor, but returned to Paris in 1800 when he was given the position of chair of mathematical physics at the College de France. Elected to the French Academy of Sciences at an unusually young age in 1803, that same year Biot was sent to investigate objects falling from the sky. His findings helped initiate the general acceptance of the existence of meteorites. Then, in 1804, he accompanied Joseph Gay-Lussac on the first balloon trip undertaken for scientific purposes.
Biot's interest in optics was spurred in 1806 when Thomas Young revived the wave theory of light. The resurgence of the theory divided the great physics minds of the day into two separate camps, one that supported the wave theory, and another that believed in the corpuscular nature of light. Biot, a member of the latter group, began devoting his time to developing mathematical support for the idea that light existed as particles. In 1808, experiments performed by Etienne-Louis Malus showed that reflected light became polarized, a finding that could only be explained by the wave theory of light. However, Biot chose to repeat and expand upon the work of Malus in hopes of attaining validation for the opposing light theory.
Although he was sometimes forced to create ingenious explanations to maintain his support of the corpuscular theory, Biot made significant advances in the study of optics. In 1815, he demonstrated that polarized light, when passing through an organic substance, could be rotated clockwise or counterclockwise, dependent upon the optical axis of the material. Further investigation showed that the angle of rotation was a direct measure of the concentration of the substance, which provided a simple mechanism for analyzing saccharine solutions. Biot's substantial research in the field of polarization also laid the groundwork for much of Louis Pasteur's work and established the science of polarimetry.
Collaboration with the physicist Felix Savart led to another of Biot's significant accomplishments. Together, in 1820, they discovered that the intensity of the magnetic field established by a wire carrying an electric current is inversely proportional to the distance from the wire. The relationship, now referred to as the Biot-Savart Law, is an elemental component of modern electromagnetic theory.
In addition to his scientific pursuits, Biot was a prolific writer. By the time he passed away in Paris on February 3, 1862, he had completed over 250 works of various types, the most renowned of which is his Elementary Treatise on Physical Astronomy (1805). Biot was widely recognized during his lifetime for his many contributions and was honored with election into the prestigious French Academy of Sciences in 1856.
Jean-Baptiste Romé de l'Isle (1736-1790) - Jean-Baptiste Romé de l'Isle was a French mineralogist who is best known as one of the founders of scientific crystallography. Within his works, he established that various shapes of crystals of the same natural or artificial substance are all closely related to each other. Moreover, measurements he took with a goniometer enabled him to determine that the angles between corresponding faces of a crystal are always the same, which is often described as the first law of crystallography.
Jean-Bernard-Leon Foucault (1819-1868) - Jean-Bernard-Leon Foucault was a French physicist who is considered one of the most versatile experimentalists of the nineteenth century. Together with the French physicist Armand Fizeau, Foucault developed a way to measure the speed of light with extreme accuracy. He also proved independently that the speed of light in air is greater than it is in water. Foucault's other contributions to the field of optics included a method of measuring the curvature of telescope mirrors, an improved technique to silver astronomical mirrors, a method of testing telescope mirrors for surface defects, and the invention of a polarizing prism to analyze polarized light.
Jesse Ramsden (1735-1800) - Jesse Ramsden was an eighteenth century English designer and manufacturer of mathematical and astronomical instruments. He is best known for the design of a telescope and microscope eyepiece (ocular) still commonly used today and bearing his name. Ramsden designed instruments of great accuracy. These included instruments to divide circles and straight lines, sextants, and vertical circles for astronomical observatories. The Ramsden eyepiece reduces blurring of the image caused by chromatic aberrations and is still used to this day in telescopes and microscopes.
Johan Sebastiaan Ploem (1927-Present) - Johan Ploem, a renowned scientist, has been a physician, educator and researcher, but is most famous for his invention of the epi-illumination cube used in fluorescence microscopy. Ploem's vertical illuminator bears his name and is commonly used today. The design consists of an excitation filter, dichroic mirror (or beamsplitter), and a barrier (or emission) filter housed together in a small cube. In addition to solving lighting problems previously incurred in fluorescence microscopy, Ploem's illumination cube has made it a simple process to change fluorescence filter combinations by rotating a knob or translating a lever.
Johann Nathanael Lieberkühn was a German physician, anatomist, and physicist. He is most widely known for development of the solar microscope, studies of the intestine, and invention of a reflector for improving microscopic viewing of opaque specimens. He was also a member of the mathematics department at the Berlin Academy of Sciences and created a lens that enhanced the use of early portable microscopes for botanical fieldwork.
During his lifetime, normal and pathological anatomies were more established sciences than microscopy. Yet, Lieberkühn's work heavily depended on the microscope. As an anatomist, his research largely focused on the digestive system. The crypts of Lieberkuhn, named in his honor, are the intestinal glands found between the villi that act as a source for digestive enzymes and various hormones. The receptors and carriers necessary for digestion and absorption are contained in the complex network of membranes. Some of Lieberkühn's anatomical specimens have survived for over 250 years. When Catherine the Great acquired them in 1765, she placed them in the Russian Medical Military Academy's Museum of Anatomy, where they remain today.
To aid his anatomical work, Lieberkühn used a simple microscope fitted with a concave mirror or reflector to study injected animal specimens with epi-illumination. The Lieberkuhn reflector, or reflecting speculum, is made of silver or another highly polished metal, and increases the amount of light illuminating a specimen. The main advantage of the reflector is that it illuminates an opaque object from almost every azimuth. Although used by many early microscope makers, for most applications the stereomicroscope and modern incident lighting have made the Lieberkuhn device obsolete. Olympus, however, still manufacturers Lieberkühn's design as an option for some of its modern microscope models that use 20-millimeter and 38-millimeter macro lenses.
Lieberkühn invented the solar microscope around 1740. Structurally similar to a microscope, in reality it was a projector that required very intense light for good resolution of fine anatomical details. The microscope was designed for showing magnifications of transparent specimens to large audiences, such as an anatomy class. The horizontal instrument was placed at the base of a window along with a mirror that collected and reflected the incident sunlight. A bi-convex lens focused the light rays onto the transparent specimen. The resulting image was enlarged and could be projected a considerable distance from the instrument and object. If sunlight was not accessible, a gas lamp or other light source could alternatively be used with the microscope.
Johann Nathanael Lieberkühn (1711-1756) - Johann Nathanael Lieberkühn was a German physician, anatomist, and physicist. He is most widely known for development of the solar microscope, studies of the intestine, and invention of a reflector for improving microscopic viewing of opaque specimens. He was also a member of the mathematics department at the Berlin Academy of Sciences and created a lens that enhanced the use of early portable microscopes for botanical fieldwork.
Johann Wilhelm Ritter (1776-1810) - Johann Ritter's greatest accomplishment is generally considered his discovery in 1801 of a previously unknown region of the solar spectrum. A year before, William Herschel had announced the existence of the infrared region, which extends past the red region of visible light. Ritter, who believed in the polarity of nature, hypothesized that there must also be invisible radiation beyond the violet end of the spectrum and commenced experiments to confirm his speculation. Ritter initially referred to the new type of radiation as chemical rays, but the title of ultraviolet radiation eventually became the preferred term.
Johannes Kepler (1571-1630) - Johannes Kepler was a sixteenth century German astronomer and student of optics who first delineated many theories of modern optics. In 1609, he published Astronomia Nova delineating his discoveries, which are now called Kepler's first two laws of planetary motion. This work established Kepler as the "father of modern science", documenting how, for the first time, a scientist dealt with a multitude of imperfect data to arrive at a fundamental law of nature.
John Dollond (1706-1761) - John Dollond was a British telescope maker who patented the discovery of the achromatic lens in the middle eighteenth century. The discovery of achromatic lenses made of flint and crown glass heralded a new era for telescope makers, but the same did not apply to the microscope. This is primarily due to technical difficulties in manufacturing the tiny achromatic compound lenses necessary for microscope objectives. The story of the achromatic lens is filled with controversy because it is widely believed that Dollond was not the inventor of the achromatic lens, but learned about its properties from lens maker George Bass.
John Kerr (1824-1907) - John Kerr was a Scottish physicist who discovered the electro-optic effect that bears his name and invented the Kerr cell. Pulses of light can be controlled so quickly with a modern Kerr cell that the devices are often used as high-speed shutter systems for photography and are sometimes alternately known as Kerr electro-optical shutters. In addition, Kerr cells have been used to measure the speed of light, are incorporated in some lasers, and are becoming increasingly common in telecommunications devices.
John S. Billings (1838-1913) - Lieutenant Colonel John S. Billings served as the curator for the United States Army Medical Museum for a ten year period from 1883 until 1893. During that time, he initiated the assembly of what has become one of the world's largest collections of microscopes. This collection was begun in 1874 by Colonel Billings' predecessor, Lieutenant Colonel George A. Otis, an Army medical officer who acquired several historic microscopes from a Philadelphia instrument maker. Visitors to Washington DC can view many of the microscopes in the Billings Collection at the National Museum of Health and Medicine at Walter Reed Army Hospital.
John Thomas Quekett (1815-1861) - Inspired by Joseph Jackson Lister's 1830 paper on achromatic microscopes, Quekett and his brother Edwin were among the seventeen founding members of the Microscopical Society of London, now known as the Royal Microscopical Society. As the world's first microscopical organization, formation of the group was of great consequence and has resulted in a significant impact on many fields related to microscopy. They began humbly, however, in 1839 at Edwin's house, Number 50 Wellclose Square in London.
Samuel Tolansky (1907-1973) - Born in Newcastle upon Tyne, England as Samuel Turlausky, Tolansky performed a significant amount of his research and developed the interference contrast microscopy technique that bears his name. Other research interests of Tolansky included the analysis of spectra to investigate nuclear spin and the study of optical illusions. Although he was primarily concerned with the spectrum of mercury, during World War II Tolansky was asked to ascertain the spin of uranium-235, the isotope capable of fission in a nuclear chain reaction.
John Tyndall (1820-1893) - From a humble background, John Tyndall rose to great heights, becoming one of the most eminent men of science during his period. The self-made man was a powerful lecturer and an influential writer who published on topics ranging from molecular physics and magnetism to mountaineering, literature, religion, and the motion of glaciers. In optics, he is most famous for his discovery of the phenomenon that came to be known as the Tyndall effect.
Hans Lippershey (1570-1619) - Hans Lippershey was a Dutch eyeglass maker who most historians believe was the inventor of the first telescope. In 1608, Lippershey applied for a patent for his telescope with the Belgian government. Lippershey called his invention a kijker, meaning looker in Dutch. Even though he was paid very well for his invention, a patent was not granted because it was felt the instrument could not be kept a secret.
Joseph Jackson Lister (1786-1869) - The nineteenth century amateur microscopist Joseph Jackson Lister is credited with making some of the most important advances toward correcting image aberrations and establishing the microscope as a powerful means of carrying out serious scientific investigations. Aided by the renowned optician William Tulley, Lister had found that by combining lenses of flint glass with those of crown glass and spacing them at specific distances from one another, the refractive problems of one were amended by the other, enabling clearer microscopic observations than ever before.
Joseph Janvier Woodward (1833-1884) - Lieutenant Colonel Joseph J. Woodward was a brilliant United States army surgeon who greatly advanced the field of photography through the microscope or photomicrography. Although microscopy was still in its infancy, by 1870, Woodward and others had established photomicrography as a means of keeping permanent records of phenomena recorded with optical microscopes. At the time, woodcut engravings were the normal method of producing illustrations, but Woodward was instrumental in advancing optical micrographs to explain various topics such as resolution in fine line gratings and detail in microscopic organisms.
Joseph Nicéphore Niepce (1765-1833) - Joseph Niepce was a French researcher who is most famous for producing the first known photograph. Exposure of the image took approximately eight hours long and, therefore, Niepce realized that further advances needed to occur before the process could be commercialized. Though he was initially hesitant, in 1829 he formed a partnership with Louis-Jacques-Mandé Daguerre in hopes of more expediently perfecting the technique. Niepce never gained widespread recognition during his lifetime, but his fundamental contributions to the silver-halide based process are forever written into the annals of photography.
Jan Jacbz Swammerdam (1637-1680) - Jan Swammerdam was a seventeenth century Dutch microscopist and naturalist who is most famous for his microscopic observations and descriptions of insect development that were published posthumously as The Bible of Nature, but is more often referred to as The Book of Nature due to a mistranslation of the title. Swammerdam pioneered the use of the microscope for zoological purposes, and is considered a founder of both comparative anatomy and entomology.
Joseph Swan (1828-1914) - Physicist and Chemist Sir Joseph Swan is remembered most for his work with incandescence for illumination purposes, as well as his research into light sources such as the carbon filament incandescent lamp and an improved version of Edison's patented light bulb. The most significant feature of Swan's lamps were that they lacked enough residual oxygen in the vacuum tube to ignite the filament, thus allowing the tungsten could glow almost white-hot without catching fire. Swan also invented the dray plate in 1871 and bromide photographic paper in 1879.
Joseph von Fraunhofer (1787-1826) - In 1813, von Fraunhofer accomplished what is often considered his greatest achievement. He independently rediscovered William Hyde Wollaston's dark lines in the solar spectrum, which are now known as Fraunhofer lines. He described a great number of the 500 or so lines he could see using self-designed instruments, labeling those most prominent with letters, a form of nomenclature that is still in favor. Fraunhofer lines would eventually be used to reveal the chemical composition of the sun's atmosphere.
Louis-Jacques-Mandé Daguerre (1787-1851) - Born near Paris, France on November 18, 1787, Louis-Jacques-Mandé Daguerre was to become both a painter and the inventor of the first successful form of photography. As an artist, Daguerre was interested in creating realistic renderings and utilized a camera obscura to aid his efforts. In hopes of simplifying the process, he became intrigued with the idea of permanently fixing an image chemically, as were many others during the period. Working with Joseph-Nicephore Niepce, Daguerre developed a photographic process termed the daguerreotype, which enjoyed widespread use in Europe for a limited time during the middle 1800s.
Leonardo da Vinci (1452-1519) - Leonardo da Vinci was a painter, sculptor, architect, engineer, scientist and genius who best represents the ideals of the Renaissance period. Da Vinci was a great engineer and inventor who designed buildings, bridges, canals, forts and war machines. He was also fascinated by birds and flying and drew designs of fantastic flying machines. Da Vinci was also intrigued with the study of optics and conducted extensive investigations and made drawings about the nature of light, reflections, and shadows. Even though it was not until over 100 years later that the first telescope was invented by Hans Lippershey, da Vinci realized the possibility of using lenses and mirrors to view heavenly bodies. Da Vinci was one of the greatest painters of all times. The Last Supper and the Mona Lisa are two of his best-known paintings.
René Descartes (1596-1650) - René Descartes is often referred to as the father of modern philosophy for his revolutionary breach from Aristotelian thought. In its place he attempted to establish a dualistic system that rested on a clear distinction between the mind, the origin of thought, and matter. He is, perhaps, most commonly remembered for his philosophical declaration, "Cogito, ergo sum" (I think, therefore I am). However, in addition to his many philosophical reflections, Descartes made significant contributions to mathematics and the sciences, including optics.
Leonhard Euler (1707-1783) - Leonhard Euler is best known as a prolific mathematician, but he also made notable contributions in optics and astronomy. In optics, Euler entered the debate on the nature of light and argued, contrary to the more popular view at the time, that light was not composed of particles. Instead, Euler's theory of light was founded upon the existence of ether, which he believed served as a pervasive medium for light vibrations. Much of Euler's work on light was published in the three-part work Dioptrica, the first volume of which was published in 1769. Within Dioptrica, the properties of lenses are discussed, the groundwork for the calculation of optical systems is established, and descriptions of microscopes and telescopes are provided.
Louis de Broglie (1892-1987) - During his long and illustrious career, de Broglie worked on various aspects of wave mechanics and published a large number of scientific treatises. He also taught theoretical physics at the Sorbonne in Paris and composed several books exploring the relationship between physics and philosophy. In addition to the Nobel Prize, de Broglie received a large number of other honors, including a number of honorary doctorate degrees, an appointment as an adviser to the French Atomic Energy Commissariat, and election into the French Academy of Sciences and the British Royal Society.
Georges de Buffon (1707-1788) - Born Georges-Louis Leclerc, the eighteenth century natural historian, mathematician, and scientist who pioneered drastic alterations in the design of lenses used in lighthouses, is often better known as Georges de Buffon, a name associated with an estate he inherited from his mother when he was about 25 years old. His method of constructing concave mirrors continues to be used in modern times and one of his inventions was a special mirror that could be used as a weapon by focusing sunlight intensely onto flammable objects.
Maksymilian Pluta (1929-2002) - While still a graduate student, Pluta began working at the Optics Department in the Institute of Precise Mechanics, which was later reorganized into the Central Optics Laboratory and then into the Institute of Applied Optics. He would remain involved with the department and Warsaw University in varying capacities throughout his entire professional career. Among the many awards bestowed upon Pluta were the Silver Cross of Merit, the Cross of Poland's Independence, and the Gold Honor Badge of the Italian Society of Mineralogy and Petrology (SIMP). He was also awarded a prestigious prize from the Foundation of Polish Science in 1995 in the field of technical science for his opus Advanced Light Microscopy, which is still available from booksellers. Pluta's landmark treatise on basic and advanced techniques is considered by many microscopists to be the most comprehensive and definitive treatment of optical microscopy yet published.
Marcello Malpighi (1628-1694) - Marcello Malpighi was a seventeenth century Italian physiologist who directed his microscope toward biological investigations and became one of the greatest microscopists of all time. Many historians regard Malpighi as the father of microscopical anatomy in both animals and plants, although he was considered more of a practical researcher than a theorist.
Marie Alfred Cornu (1841-1902) - Cornu made a wide variety of contributions to the fields of optics and spectroscopy, but is most noted for significantly increasing the accuracy of contemporary calculations of the speed of light. In 1878, Cornu made adjustments to an earlier method of measuring the velocity of light developed by Armand Fizeau in the 1840s. The changes and improved equipment resulted in the most accurate measurement taken up to that time, 299, 990 km per second. Other significant accomplishments of Cornu include a photographic study of ultraviolet radiation and the establishment of a graphical approach, known as the Cornu spiral, for calculating light intensities in Fresnel diffraction.
Marvin Lee Minsky (1927-Present) - While at Harvard University, Marvin Minsky made his primary contribution to the field of optics by inventing the confocal scanning microscope. Despite the theoretical benefits of the confocal approach for biological purposes, Minsky's microscope originally generated little interest. In hindsight it has become apparent that the technology of the period limited Minsky's demonstration of the potential of the confocal approach. Yet, years later, with the advent of such applicable devices as lasers, sensitive low-noise photodetectors, and fast microcomputers with image processing capabilities, Minsky's microscopy technique has become widespread in biological research.
Max Berek (1886-1949) - Max Berek was a German physicist and mathematician, associated with the firm of E. Leitz, who designed a wide spectrum of optical instruments, in particular for polarized light microscopy and several innovative camera lenses. Professor Berek is credited as the inventor of the Leica camera lens system at their Wetzlar factory.
Georges Nomarski (1919-1997) - A Polish born physicist and optics theoretician, Georges Nomarski adopted France as his home after World War II. He is credited with numerous inventions and patents, including a major contribution to the well-known differential interference contrast (DIC) microscopy technique. Also referred to as Nomarski interference contrast (NIC), the method is widely used to study live biological specimens and unstained tissues.
Max Planck (1858-1947) - Max Planck, a German physicist, is best known as the originator of the quantum theory of energy for which he was awarded the Nobel Prize in 1918. His work contributed significantly to the understanding of atomic and subatomic processes. Planck made significant contributions to science throughout his life. He is recognized for his successful work in a variety of fields including, thermodynamics, optics, statistical mechanics, and physical chemistry.
Michael Faraday (1791-1867) - When Michael Faraday was born to a blacksmith in Surrey, England on September 22, 1791, there was little expectation that he would become one of the most influential scientists of the nineteenth century. Before his career had ended, Faraday succeeded in discovering the aromatic hydrocarbon benzene, built the first electric motor, and his studies spawned the vast field of cryogenics. He also invented the transformer and dynamo, and then established the principle of electromagnetic induction in 1831 to explain his experimental findings. By 1832, Faraday had also revealed the laws of electrolysis that bear his name. In 1845, Faraday began studying the influence of magnetic fields on plane-polarized light waves, and discovered that the plane of vibration is rotated when the light path and the direction of the applied magnetic field are parallel, a phenomenon now known as the Faraday effect. In his attempts to prove that all matter reacts to a magnetic force, Faraday established the classes of materials known as paramagnetic and diamagnetic, and ultimately revolutionized contemporary notions of space and force.
Michael Kasha (1920-Present) - Michael Kasha has made numerous discoveries and contributions to the scientific world, greatly influencing the development of molecular electronic spectroscopy and molecular photochemistry. His work concerning excited-state radiationless transitions resulted in what came to be known as Kasha's Rules, and he also demonstrated that a solvent containing heavy atoms could generate singlet-triplet transitions of organic molecules, a phenomenon eventually designated the Kasha effect.
Nicolas Zucchi (1586-1670) - Nicolas Zucchi was a Jesuit preacher who designed one of the earliest reflecting telescopes in 1616. Zucchi described his reflecting telescope and his invention of it in the treatise Optica philosophia experimentalis et ratione a fundamentis constituta, which was published in the 1650s. The landmark work reportedly influenced James Gregory and Sir Isaac Newton, both of whom built improved reflecting telescopes in the 1660s.
Pavel Alekseyevich Cherenkov (1904-1990) - In 1958, Pavel Cherenkov was awarded the Nobel Prize in Physics for his discovery and characterization of the Cherenkov effect, an optical phenomena that occurs when charged particles move at speeds greater than the speed of light. Today, the Cherenkov effect is considered invaluable to the field of spectroscopy, as well as to the study of cosmic rays and other high-speed particles. Cherenkov counters, which are specialized instruments that can measure particle velocity by using the light emitted by Cherenkov radiation, have garnered widespread use by experimental scientists studying particle and nuclear physics.
Nicolaus Copernicus (1473-1543) - Perhaps realizing what the consequences might be for openly opposing long-held beliefs and standard Church doctrine, Nicolaus Copernicus postponed the publication of his complete body of work supporting the heliocentric theory for more than thirty years. A young scholar Georg Joachim Rheticus, who lived with Copernicus for a period between 1539 and 1542, was integral in moving the project forward. It was under his name that a brief account of Copernicus's heliocentric theory known as the Narratio Prima was published in 1540.
Niels Bohr (1885-1962) - Building on Ernest Rutherford's work on the nucleus, Bohr developed a new theory of the atom, which he completed in 1913. The work proposed that electrons travel only in certain orbits and that any atom could exist only in a discrete set of stable states. Bohr further held that the outer orbits, which could hold more electrons than the inner ones, determine the atom's chemical properties and conjectured that atoms emit light radiation when an electron jumps from an outer orbit to an inner one. Although Bohr's theory was initially viewed with skepticism, it earned him the Nobel Prize in physics in 1922 and was eventually expanded by other physicists into quantum mechanics.
Ole Christensen Roemer (1644-1710) - Roemer' s greatest achievement was the first relatively accurate measurement of the speed of light, a feat he accomplished in 1676. At the Royal Observatory in England, Roemer's studies of Jupiter's moon Io and its frequent eclipses enabled him to predict the periodicity of an eclipse period for the moon. By applying the relatively inaccurate calculations for the distances between Earth and Jupiter available during the seventeenth century, Roemer was able to approximate the speed of light to be 137,000 miles (or 220,000 kilometers) per second.
Otto Schott (1851-1935) - Schott was considered a leading pioneer in glass chemistry due to his creation of new glass types of high quality for use in optics and in the industry. Together with Ernst Abbe and Carl Zeiss, Schott formed the Scott Glass Works, which produced glass for apochromatic microscope objective lenses virtually free of chromatic aberration. Microscopes equipped with these advanced lenses produce the highest degree of resolution and are widely utilized today.
Joseph Nicéphore Niepce (1765-1833) - Joseph Niepce was a French researcher who is most famous for producing the first known photograph. Exposure of the image took approximately eight hours long and, therefore, Niepce realized that further advances needed to occur before the process could be commercialized. Though he was initially hesitant, in 1829 he formed a partnership with Louis-Jacques-Mandé Daguerre in hopes of more expediently perfecting the technique. Niepce never gained widespread recognition during his lifetime, but his fundamental contributions to the silver-halide based process are forever written into the annals of photography.
Paul Gottlieb Nipkow (1860-1940) - Paul Nipkow was a German engineer and inventor who proposed the world's first electromechanical television system. The innovative system was based upon a simple device known as the Nipkow disk, which consisted of either metal or cardboard and was perforated with a series of square holes arranged in a spiral. Nipkow once used his device to transmit a visual image from London to Paris, but the system was never developed for commercial use. The Nipkow disk is currently used extensively in reflected light confocal scanning microscopy to produce images that can be viewed in real time through the microscope eyepieces. Several thousand points are simultaneously illuminated on the disk to mimic the effect of several thousand confocal microscopes running in parallel. The rapidly spinning disk fills spaces between the holes to create a real-time confocal image.
Pavel Alekseyevich Cherenkov (1904-1990) - In 1958, Pavel Cherenkov was awarded the Nobel Prize in Physics for his discovery and characterization of the Cherenkov effect, an optical phenomena that occurs when charged particles move at speeds greater than the speed of light. Today, the Cherenkov effect is considered invaluable to the field of spectroscopy, as well as to the study of cosmic rays and other high-speed particles. Cherenkov counters, which are specialized instruments that can measure particle velocity by using the light emitted by Cherenkov radiation, have garnered widespread use by experimental scientists studying particle and nuclear physics.
Antonie van Leeuwenhoek (1632-1723) - Antonie van Leeuwenhoek was a famous Dutch scientist who made simple microscopes that were able to magnify objects over 275 times, an amazing feat for the period. He studied Protists, plant cells, various types of algae, and was the first person to view bacteria, which he termed "animalcules". Leeuwenhoek's curiosity about this microscopic world and his diligence in recording his painstaking observations enabled him to share with others what he had seen with his microscopes.
Philipp Eduard Anton Lenard (1862-1947) - Philipp Lenard is somewhat of controversial figure in the history of science. He undoubtedly made significant contributions to the field of physics, but suffered in reputation in his later life due to his alignment with the Nazi party and his unfounded condemnation of other scientists, especially Albert Einstein and other individuals with Jewish backgrounds. Ironically, it was Einstein's theoretical work that helped make sense of some of Lenard's most important experimental work on the photoelectric effect and which greatly influenced the Nobel Foundation's decision to award the 1905 Nobel Prize for Physics to Lenard.
Richard Adolph Zsigmondy (1865-1929) - Richard Zsigmondy was an Austrian chemist and professor who invented the ultramicroscope and used the device to make numerous discoveries regarding the nature of colloids. The instrument, completed in 1903, illuminated colloidal particles with an intense beam of light oriented in a position perpendicular to the microscope's optical axis. As particles scattered the incident light, their movements could be seen as flashes against a dark background. His efforts to improve upon the design of the ultramicroscope resulted in the invention of the immersion ultramicroscope in 1913. In 1925, Zsigmondy received the crowning glory of his career when he was awarded the Nobel Prize in Chemistry for his inventions and colloid research.
Robert Andrews Millikan (1868-1953) - Robert Millikan was an American physicist who was awarded the Nobel Prize for Physics for his experiments on the photoelectric effect and on the charge carried by an electron. The renowned scientist also is well known for his studies of cosmic rays and his role in establishing the California Institute of Technology as a leading research establishment. Throughout his life, Millikan was dedicated to reconciling the realms of science and religion, publishing many books on the topic.
Robert Day Allen (1927-1986) - Robert Day Allen was a renowned microscopist, a prominent researcher of cell motility processes, and a co-developer of video-enhanced contrast microscopy ((VEC)), which is a modification of the traditional form of differential interference contrast (DIC) microscopy. Along with Georges Nomarski and G. B. David, Allen assisted the Carl Zeiss Optical Company in developing a Nomarski differential interference microscope for transmitted light applications. In a hallmark paper published in Zeitschrift für wissenschaftliche Mikroskopie und mikroskopische Technik, Allen and his colleagues defined the basic principles of the DIC technique and the interpretation of images.
Robert Grosseteste (1175-1253) - Grosseteste was particularly interested in astronomy and mathematics, and he asserted that the latter was essential to investigations of natural phenomena. Consequently, his study of light often took a mathematical turn, resulting in a refinement of optical science. In his investigations of rainbows, comets, and other optical phenomena, he notably made use of both observational data and mathematical formulations. Moreover, Grosseteste was an early proponent of the need for experimental support of scientific theories and carried out numerous experiments with mirrors and lenses.
Robert Hooke (1635-1703) - Robert Hooke was an experimental scientist who lived in seventeenth century England where he made major contributions to the emerging discipline of optical microscopy. Hooke's interest in microscopy and astronomy is exemplified by the treatise Micrographia, his best known work on optical microscopy, and a volume on comets, Cometa detailing his close observation of the comets occurring in 1664 and 1665. Hooke observed a wide diversity of organisms in the microscope, including insects, sponges, bryozoans, diatoms, and bird feathers. Perhaps less well known, Robert Hooke coined the term "cell", in a biological context, as he described the microscopic structure of cork like a tiny, bare room or monk's cell in his landmark discovery of plant cells with cell walls.
Robert Wilhelm Bunsen (1811-1899) - Robert Bunsen is most familiar with scientists today in association with the Bunsen burner, a device found in educational chemistry laboratories around the word. Ironically, Bunsen only made minor alterations to the familiar burner, rather than inventing it, and made many more generally important contributions to science. Indeed, in work he carried out with Gustav Kirchhoff, Bunsen helped lay the foundations of spectroscopy, a field that has had a tremendous impact on the modern understanding of the world.
Robert Bunsen is most familiar today in association with the Bunsen burner, a device found in educational chemistry laboratories around the word. Ironically, Bunsen only made minor alterations to the familiar burner, rather than inventing it, and made many more generally important contributions to science. Indeed, in work he carried out with Gustav Kirchhoff, Bunsen helped lay the foundations of spectroscopy, a field that has had a tremendous impact on the modern understanding of the world.
Bunsen was born in Göttingen, Germany on March 31, 1811 and was raised in an environment conducive to learning, his father being a professor of modern languages at the university there. Before he was twenty years old, Bunsen had obtained his doctorate in chemistry at Göttingen University. He spent several years following this achievement traveling through Western Europe. Upon his return, Bunsen taught at several different universities, including institutions in Marburg and Breslau, before settling at Heidelberg, where he taught from 1852 until his retirement, and established an exceptional chemistry department. There he was habitually absorbed by his experiments and analyses, never finding the time nor the inclination to marry.
In 1834, Bunsen discovered that hydrated ferric oxide was an antidote to arsenic poisoning, a finding that was personally significant to him since he nearly died of arsenic poisoning several years later while carrying out studies of cacodyl, an arsenical oil. During his investigations of the toxic compound he also became blinded in one eye from an explosion in the laboratory. These setbacks led him to ultimately abandon organic chemistry research. He was extremely inventive, however, and found many other topics to occupy his time. In 1857, he published Gasometrische Methoden, a work that detailed his methods for obtaining volume measurements of gases, and later developed several new devices, including the filter pump (1868), a sensitive ice calorimeter (1870), and the vapor calorimeter (1887). He also was the inventor of what has come to be known as the Bunsen cell (a carbon-zinc electric cell) and the grease-spot photometer, which he developed in order to quantify the amount of light produced by the cell.
Bunsen's investigations with magnesium, which he was the first to obtain in the pure metallic state and to find that it was a brilliant illuminating agent, reportedly influenced his interest in the relationship between light and chemicals, and Bunsen became a pioneer of photochemistry. In this field, he collaborated with Sir Henry Roscoe for nearly a decade, the pair primarily concentrating on the formation of hydrogen chloride from gaseous hydrogen and chlorine, which is specifically related to the amount of light present. In the late 1850s, Bunsen suddenly broke off his work with Roscoe due to a new collaborative effort with the physicist Gustav Kirchhoff, whom he had become acquainted with in 1851 and had arranged to be given an appointment at Heidelberg University. The momentous nature of Kirchhoff's discovery that similarly colored flames could be distinguished from one another by utilizing a prism to divide the light into its constituent rays and that all pure substances have their own characteristic spectra appears to have led to Bunsen's decision. He subsequently dedicated his laboratory to the nascent field of analytical spectroscopy (the study of the emission and absorption of light and other radiation by matter in terms of their relationship to the wavelength of the radiation).
During their spectroscopic investigations, Bunsen and Kirchhoff discovered cesium and rubidium, and more importantly, made it possible for a more detailed understanding of the composition of the sun, stars, and other celestial bodies to be obtained. It was also in the course of these studies that Bunsen redesigned the burner in his laboratory, which has become the well-known Bunsen burner. The improved device allowed for more ready control over the heat of the flame obtained. Bunsen and Kirchhoff's research was further aided by their development of the spectroscope, which continues to be a vital optical instrument even today.
Bunsen's illustrious career made him highly esteemed by his students and colleagues, and he received many honors. He was elected into the Chemical Society of London (1842), the French Academy of Sciences (1853), and the Royal Society of London (1858). The latter association bestowed him with the Copley Medal in 1860, and in 1877 Bunsen and Kirchhoff became the recipients of the very first Davy Medal. In 1898, the year before he died, Bunsen was awarded the prestigious Albert Medal by the Royal Society for the Encouragement of Arts. Despite his numerous tributes, Bunsen maintained a reputation for modesty and even once characteristically claimed of his awards that, "Such things had value for me only because they pleased my mother; she is now dead."
Roger Bacon (1214-1294) - Roger Bacon was an English scholastic philosopher who was also considered a scientist because he insisted on observing things for himself instead of depending on what other people had written. Bacon's writings included treatises on optics (then called perspective), mathematics, chemistry, arithmetic, astronomy, the tides, and the reformation of the calendar. His skill in the use of optical and mechanical instruments caused him to be regarded by many as a sorcerer. Bacon was acquainted with the properties of mirrors, knew the powers of steam and gunpowder, had a working knowledge in microscopy, and possessed an instrument very much like a modern telescope.
Roger Bacon was an English scholastic philosopher who was also considered a scientist because he insisted on observing things for himself instead of relying on what other people had written. Bacon was born into a wealthy family in 1214 and died in 1294. He was trained in the classics, geometry, arithmetic, music and astronomy and was a student at the University of Paris as a young man where he received the degree of Doctor of Theology. Bacon spent forty years studying and lecturing on the natural sciences at Oxford University in England. For these efforts, he is considered to be the most important cultivator of the natural sciences during the Middle Ages.
Bacon's writings included treatises on optics (then called perspective), mathematics, chemistry, arithmetic, astronomy, the tides, and the reformation of the calendar. His skill in the use of optical and mechanical instruments caused him to be regarded by many as a sorcerer. Bacon was acquainted with the properties of mirrors, knew the powers of steam and gunpowder, had a working knowledge in microscopy, and possessed an instrument very much like a modern telescope. He claimed that his telescope could make the most distant object appear near, that it could make stars appear at will, and even further, that it had the power of visualizing future events.
Bacon once frightened his students by creating a rainbow by passing light through some glass beads. This demonstration marked one of the earliest attempts to duplicate a natural phenomenon in the laboratory. Bacon believed that the Earth was spherical and that one could sail around it. He estimated the distance to the stars at 130 million miles, and he used a camera that projected an image through a pinhole to observe solar eclipses. His work was so popular that it encouraged others to experiment on their own, and by so doing helped bring about the Renaissance.
In 1266, Bacon sent a letter to Pope Clement IV suggesting improvements in the scientific curricula and installing laboratory experimentation in the educational system. He made the bold claim that the entire educational system needed to be rebuilt, and that the foundations for this revitalization could be found in his work. Bacon gave to the pope a proposal for a universal encyclopedia of knowledge and asked for a team of collaborators to be coordinated by a body in the Church to build the encyclopedia. Unfortunately, Pope Clement was unaccustomed to receiving proposals such as Bacon's and misunderstood his request. Thinking that Bacon's encyclopedia of science already existed, the Pope demanded to see the documents. In the confusion, Pope Clement bound Bacon by a papal oath of secrecy to reveal all of his beliefs and philosophies. Because Bacon revered the pope and could not disobey, he quickly composed a three-volume encyclopedia on the sciences. These works consisted of the Opus Majus (Great Work), the Opus Minus (Lesser Work) and the Opus Tertium (Third Work), explaining to the pope the rightful role of the sciences in the university curriculum and the interdependence of all disciplines.
Unfortunately, in 1268 Pope Clement IV died. With the Pope's death, Bacon's chances of seeing the encyclopedia project through to completion vanished and even worse, a defeat for the prospect of revamping the university curriculum. Undaunted, Bacon embarked on another great project and started to write the Communia naturalium (General Principles of Natural Philosophy) and the Communia mathematica (General Principles of Mathematical Science). He never finished this work and only part of it was published.
In 1277, The Minister General of the Franciscans condemned Bacon's work because of the "suspect novelties" it contained. In response, the loyal Brothers of the Order had him imprisoned. Bacon had always submitted his writings to the judgment of the Church, and now appealed to the new Pope. The appeal was lost and Bacon was imprisoned, but the exact amount of time he served is unknown. Some sources say two years, others much longer. His last work, published the year of his death, was a stinging reproach of a corrupted Church. Although largely incomplete, Bacon's last contribution found him just as determined as any time in his life to expose ignorance.
Samuel Tolansky (1907-1973) - Born in Newcastle upon Tyne, England as Samuel Turlausky, Tolansky performed a significant amount of his research and developed the interference contrast microscopy technique that bears his name. Other research interests of Tolansky included the analysis of spectra to investigate nuclear spin and the study of optical illusions. Although he was primarily concerned with the spectrum of mercury, during World War II Tolansky was asked to ascertain the spin of uranium-235, the isotope capable of fission in a nuclear chain reaction.
Savile Bradbury was a renowned professor of anatomy and expert in both optical and electron microscopy. He was born in Halifax, England on February 6, 1931 but moved with his family to the town of Derby at the beginning of World War II. There he attended grammar school before being awarded a state scholarship to the University of Oxford. However, he decided to fulfill his duty of National Service before continuing his education. An accomplished flutist, Bradbury joined the Royal Air Force and became a member of the Central Band, which provided him with the opportunity to travel extensively during his two-year service.
His military obligation complete, in 1951 Bradbury began coursework at Oxford's Brasenose College, where he focused his studies on zoology. After receiving his undergraduate degree, Bradbury decided to pursue his doctorate, which was awarded in 1958. By the time his formal education was complete, Bradbury was an extremely skilled microscopist, a characteristic that garnered him an appointment as a demonstrator in the Department of Human Anatomy. He continued in the post until 1963, when he was promoted to University Lecturer, a title he held until his retirement in 1990.
In addition to his work at Oxford, Bradbury was heavily involved in a number of scientific organizations. His interest in microscopy inspired him to join the Royal Microscopical Society in 1959. He became a council member of the organization in 1962 and continued to serve the group in varying capacities for most of his career. Also a member of the Quekett Microscopical Society, Bradbury had the rare privilege of being elected to honorary membership of both of the organizations, a testament to his tremendous capabilities. Other notable groups with which he was associated include the Anatomical Society and the British Society for the History of Science.
Bradbury published his first paper in 1955, and more than 80 more were to follow over the rest of his career. He also authored, or co-authored, 13 books, many of them staples of the scientific community. Through works such as The Evolution of the Microscope (1967), An Introduction to the Optical Microscope (1989), and Introduction to Light Microscopy (1998), Bradbury pioneered efforts to both preserve the history of microscopy and to introduce the field to a new generation of scientists. He was also a talented lecturer, and reached thousands of developing minds through his educational and interesting presentations.
In Bradbury's later years, he continued to be very active in scientific circles and with Oxford University, despite his formal retirement. Though he passed away on November 29, 2001 the legacy of his many achievements lives on. With a seemingly indefatigable enthusiasm, Bradbury shared his passion for microscopy and science with all who knew him and, through his written works, will continue to do so for many years to come.
Shinya Inoué (1921-Present) - Shinya Inoué is a microscopist, cell biologist, and educator who has been described as the grandfather of modern light microscopy. The pioneering microscopist heavily influenced the study of cell dynamics during the 1980s through his developments in video-enhanced contrast microscopy (VEC), which is a modification of the traditional form of differential interference contrast (DIC) microscopy. Inoué developed the method in parallel with Robert and Nina Allen and described his work at the same meeting of the American Society for Cell Biology as his fellow scientists. His seminal work, Video Microscopy, was published in 1986, and a second revised and updated edition, co-authored with Kenneth Spring, followed in 1997. The book is a cornerstone of microscopical knowledge and is highly regarded throughout the scientific community.
Sir David Brewster (1781-1868) - Sir David Brewster was a Scottish physicist who invented the kaleidoscope, made major improvements to the stereoscope, and discovered the polarization phenomenon of light reflected at specific angles. In his studies on polarized light, Brewster discovered that when light strikes a reflective surface at a certain angle (now known as Brewster's Angle), the light reflected from that surface is plane-polarized. He elucidated a simple relationship between the incident angle of the light beam and the refractive index of the reflecting material.
Sir David Brewster was a Scottish physicist who invented the kaleidoscope, made major improvements to the stereoscope, and discovered the polarization phenomenon of light reflected at specific angles. Brewster was born in Jedburgh, Scotland in 1781 and grew to become a brilliant student who entered the University of Edinburgh at the age of 12 to study the ministry. He was a prolific writer and became editor of the Edinburgh Magazine in 1802 and the Edinburgh Encyclopedia in 1808. In 1799 as a teenager, Brewster's interests turned to physics with a keen focus on optics, and he constructed several telescopes while dabbling in the physics of light. Brewster was a licensed minister of the Church of Scotland, but never practiced this career, instead pursuing the finer aspects of optics and light.
Brewster's career blossomed while he was in his late twenties and early thirties. At that time, he was intensely pursuing details of the theory of light and wrote his first paper Some Properties of Light in 1813. One of Brewster's most important contributions to the science of physics was his work on polarization of light by reflection and biaxial crystals. To aid in his experiments, Brewster often constructed his own tools and even improved many technical instruments of the period.
In his studies on polarized light, Brewster discovered that when light strikes a reflective surface at a certain angle (now known as Brewster's Angle), the light reflected from that surface is plane-polarized. He elucidated a simple relationship between the incident angle of the light beam and the refractive index of the reflecting material. When the angle between the incident beam and the refracted beam equals 90 degrees, the reflected light becomes polarized. This rule is often used to determine the refractive index of materials that are opaque or available only in small quantities.
Brewster was elected to the Royal Society in 1815 and eventually was one of only a handful of scientists to be awarded all three principal medals of the Society. For his work in optics, Brewster was awarded the Copley Medal in 1815, the Rumford Medal in 1818, and the Royal Medal in 1830. He also was a founder of the British Association for the Advancement of Science.
An energetic enthusiast of color, Brewster invented the kaleidoscope in 1816 and patented it the following year. He published his extensive studies on the theory, design, and construction of kaleidoscopes in 1819 in a volume entitled Treatise on the Kaleidoscope. Apparently there were some problems with the registration of his patent, because he was not able to enforce infringements and many companies began to offer custom versions of the kaleidoscope without paying royalties. The instrument ignited a craze in the early nineteenth century and quickly became a household toy for both children and adults alike.
Brewster was deeply interested in photography and had many conversations with Fox Talbot about the design of Talbot's Calotype process. He favored this process over the Daguerreotype and is quoted:
Sir George Biddell Airy (1801-1892) - Sir George Airy was a distinguished nineteenth century English Astronomer Royal who carried out optical research and first drew attention to the visual defect of astigmatism. Airy manufactured the first correcting eyeglasses (1825) using a cylindrical lens design that is still in use. The diffraction disks that bear his name (Airy Disks) were discovered in the spherical center of a wavefront traveling through a circular aperture. These diffraction patterns form the smallest unit that comprises an image, thus determining the limits of optical resolution.
Sir George Airy was a distinguished nineteenth century English Astronomer Royal who carried out optical research and first drew attention to the visual defect of astigmatism. After graduating from Trinity College, Cambridge in 1823, Airy worked as a mathematics tutor, but was later better-known for his skills in Latin and ancient Greek, poetry, history, theology, architecture, engineering, geology, and his then-controversial beliefs in separating education from religion. By 1826, Airy's interest in astronomy increased dramatically when he was a Professor of Mathematics at Cambridge University. He published a treatise entitled Mathematical Tracts on Physical Astronomy and by 1828, became Professor of Astronomy and Director of the Cambridge Observatory.
Under Airy, the Observatory blossomed from simply providing data to the Royal Navy to a major research institution with the addition of the Altazimuth telescope in 1847 and the Airy Transit Circle. Departments in magnetism and meteorology were subsequently added and regular observations of sunspots and spectroscopy were conducted on a routine basis. From studying eclipses to measuring gravity, Airy's extra-observatory activities were varied, and included his supervision of the first transatlantic telegraph cable placement and the construction of Big Ben's chimes. It took four offers by the Queen, before he agreed to become Sir George in July 1872. Known for his sarcasm and caustic personality, Airy had an ongoing battle with Charles Babbage in which he prevailed professionally and financially to the detriment of science. Airy's infamy ranges from ignoring John Adams' discovery of Neptune to dismissing Michael Faraday's field theory.
In the field of optics, Airy's water telescope helped erase the antiquated theory of æther, the substance in air through which light was supposed to travel, laying the groundwork for Einstein's Theory of Relativity. Suffering from astigmatism, he manufactured the first correcting eyeglasses (1825), with a cylindrical lens design that is still in use. The diffraction disks that bear his name (Airy Disks) were discovered in the spherical center of a wavefront traveling through a circular aperture. These diffraction patterns form the smallest unit that comprises an image, thus determining the limits of optical resolution.
Sir Isaac Newton (1642-1727) - Sir Isaac Newton, who was ironically born the same year that Galileo died, is popularly known as one of history's greatest scientists. Many of his discoveries and theories in the areas of light, color, and optics form the basis for current scientific thought in these disciplines. In addition to his extensive work in optics, Newton is perhaps best known for his theory of universal gravitation. He also is considered one of the inventors of calculus along with German mathematician Gottfried Leibniz. Newton's three laws of motion are considered basic to any physics student's education.
Theodore Harold Maiman (1927-Present) - Theodore Maiman is best remembered for constructing the world's first laser, a device that has transcended the field of optics to find a diversity of applications in the modern world. In May of 1960, Maiman built his prototype laser using a synthetic ruby rod silvered at both ends to reflect light. Small enough to be held in the palm of the hand, when the atoms in the rod were excited by an intense beam of light from a xenon lamp, a release of energy was initiated and an internal chain reaction occurred that caused the energy to bounce back and forth within the rod. When the energy built up to a certain level, it escaped from one end of the ruby rod to form an intense beam of monochromatic light centered at 694.3 nanometers.
Thomas Alva Edison (1847-1931) - Thomas Edison was an American inventor who achieved his greatest successes in his Menlo Park laboratory and was called the "Wizard of Menlo Park." This research and development laboratory was the first of its kind anywhere; it became a model for later, modern research and development facilities such as Bell Laboratories. It was during this period of his life that Edison and his staff were responsible for many inventions and innovations. More patents were issued to Edison than have been issued to any other single person in United States history, a total of 1,093. Edison is perhaps best known for his invention of the incandescent light bulb.
Thomas Young (1773-1829) - Thomas Young was an English physician and a physicist who was responsible for many important theories and discoveries in optics and in human anatomy. His best known work is the wave theory of interference. Young was also responsible for postulating how the receptors in the eye perceive colors. He is credited, along with Hermann Ludwig Ferdinand von Helmholtz, for developing the Young-Helmholtz trichromatic theory.
Tycho Brahe (1546-1601) - Tycho Brahe was a Danish astronomer who made the most accurate observations possible without the aid of a telescope. On November 11, 1572 he observed what seemed to be a bright new star near Cassiopeia and studied it for the next 18 months. Brahe was surprised to find that the star seemed to be further away than the moon and that it intensified in brightness before eventually slowly fading out of view. The event was extremely significant because it would not have been possible if the Aristotelian conception of a harmonious and unchanging universe were correct. Brahe attempted to modify the Ptolemaic theory to coincide with his observations, and proposed the Tychonic system, in which the Earth remained immobile, but the sun served as a secondary center. Although it was an interesting attempt at a compromise between two completely different viewpoints, the Tychonic system never garnered much support.
Tycho Brahe was a Danish astronomer who made the most accurate observations possible without the aid of a telescope. His detailed astronomical findings led many to question the Aristotelian notion of a perfect and unchanging universe and laid the groundwork for future scientific breakthroughs.
Brahe was born the son of a nobleman on December 14, 1546, the surviving member of a pair of twin boys. He was raised, however, by a wealthy, childless uncle and became his heir. His rank afforded him an excellent education and Brahe studied at the universities of Copenhagen and Leipzig, among others. Due to his uncle's desires Brahe entered school with the intention to prepare for a career in politics, but his own predilections led him to the field of astronomy. A discrepancy between the predicted and observed time of a partial eclipse of the sun perturbed Brahe, and he dedicated his life to making astronomy a more precise science in order to alleviate such inconsistencies. The death of his uncle in 1565 enabled him to spend more time traveling and exploring his interests. Brahe accumulated scientific instruments, began composing his own star charts, and dabbled in alchemy.
Brahe returned to Denmark in 1570, where he lived with another uncle and set up his own observatory. From the homemade post, Brahe made a discovery that would make a profound impact on his life and on astronomy. On November 11, 1572 he observed what seemed to be a bright new star near Cassiopeia and studied it for the next 18 months. Brahe was surprised to find that the star seemed to be further away than the moon and that it intensified in brightness before eventually slowly fading out of view. The event was extremely significant because it would not have been possible if the Aristotelian conception of a harmonious and unchanging universe were correct.
After publishing a brief tract regarding his discovery in 1573, Brahe became an important figure in scientific circles. In 1574, he lectured on astronomy at the University of Copenhagen before embarking on a tour of Germany, on which he interacted with a number of other prominent astronomers. Fearing that Brahe would permanently relocate to Germany, in 1576, King Frederick II of Denmark offered to provide him with the money to develop a state of the art observatory on the island of Hven, which was located near Copenhagen. Brahe accepted the proposition and construction soon began on the observatory that would be known as Uraniborg, or Castle of the Heavens. The facility, the first of its kind, attracted leading scholars from around the world.
In 1577, Brahe observed a bright comet, another phenomenon that did not correspond to the Aristotelian discipline. His measurements revealed that it, too, was more distant from the Earth than the moon, and could not, therefore, be an atmospheric occurrence as was suggested by Aristotle. Moreover, Brahe determined that the comet's path was elongate, rather than circular, which would mean that it would have to travel through the impenetrable spheres that were believed to carry the planets through the sky, a concept of Ptolemy. Brahe published his troubling findings that same year and also proposed a new theory regarding the system of the planets.
Unwilling to accept Copernicus's heliocentric theory, Brahe attempted to modify the Ptolemaic theory to coincide with his observations. In the Tychonic system, the Earth remained immobile, but the sun served as a secondary center. Mercury and Venus orbited around the sun, forming a small system that revolved around the Earth. Mars, Jupiter, and Saturn, Brahe suggested, orbited both the sun and the Earth, while the stars remained in a fixed sphere that made a full revolution each day. Although it was an interesting attempt at a compromise between two completely different viewpoints, the Tychonic system never garnered much support.
Upon the death of Frederick II, Brahe lost his financial backing and decided to relocate to Prague in 1597. There he again set up his instruments, many of which had been salvaged from his observatory at Hven, and obtained a new assistant, Johannes Kepler. When Brahe died following a brief illness in 1601, Kepler inherited all of Brahe's data and equipment. This act of bequeathal was yet another important scientific contribution made by Brahe, since Kepler would use the information to develop his system of planetary motion.
Walter C. McCrone (1916-2002) - Walter McCrone was an optical microscopist from Chicago who founded the world-famous McCrone Research Institute and made a significant number of contributions to microscopy as an investigational tool. McCrone's acclaimed work with the Shroud of Turin received worldwide attention in 1978 when he concluded that the Turin Shroud is a medieval painting. This observation was vindicated by radioactive carbon-14 dating techniques in 1988. In 2000, McCrone received the American Chemical Society National Award in Analytical Chemistry for his work on the Turin Shroud and for this enduring patience for the defense of his work for nearly 20 years.
Warren de la Rue (1815-1889) - Warren de la Rue was a nineteenth century microscopist, astronomer, and chemist who invented the photoheliograph. His investigations of photoactive chemicals, electrical discharge in gaseous substances, and batteries are especially notable, the latter resulting in the invention of the silver chloride cell. De la Rue was also intrigued by optics and carried out many experiments in the field, some of which tested the wave theory of light. He is most remembered, however, for his pioneering role in astrophotography.
Henri Hureau de Sénarmont (1808-1862) - Sénarmont was a professor of mineralogy and director of studies at the École des Mines in Paris, especially distinguished for his research on polarization and his studies on the artificial formation of minerals. He also contributed to the Geological Survey of France by preparing geological maps and essays. Perhaps the most significant contribution made by de Sénarmont to optics was the polarized light retardation compensator bearing his name, which is still widely utilized today.
Willebrord Snell (1580-1626) - Willebrord Snell was an early seventeenth century Dutch mathematician who is best known for determining that transparent materials have different indices of refraction depending upon the composition. Snell discovered that a beam of light would bend as it enters a block of glass, and that the angle of bending was dependent upon the incident angle of the light beam. Light traveling in a straight line into the glass will not bend but, at an angle, the light is bent to a degree proportional to the angle of inclination. In 1621, Snell found a characteristic ratio between the angle of incidence and the angle of refraction. Snell's law demonstrates that every substance has a specific bending ratio-the "refractive index. The greater the angle of refraction, the higher the refractive index for a substance.
William Fox Talbot (1800-1877) - William Fox Talbot, an English chemist, philosopher, mathematician, linguist, and Egyptologist, is best known for the innovative photographic techniques he developed. His work in the mid-1800s is the foundation upon which modern photography is based. Bad timing, however, has left Talbot a footnote to Louis-Jacques-Mandé Daguerre who is more popularly known as the founder of modern photography. Daguerre publicly announced his method for creating a plate from which a single photographic print could be made. Only a few weeks after this announcement, Talbot revealed his innovation, the Calotype.
William Henry Bragg (1862-1942) - Sir William Henry Bragg was a noted British physicist and President of the Royal Society who had numerous research interests, but the work that earned him a rank as one the great leaders in science was his historic advancements in X-ray crystallography. Working with his son William Lawrence Bragg, he developed a method of bombarding single crystals with high-energy X-rays emitted by specially constructed vacuum tubes. By examining the pattern of X-rays diffracted by various crystals, Bragg and his son were able to establish some fundamental mathematical relationships between an atomic crystal structure and its diffraction pattern. For this achievement, William Henry Bragg and William Lawrence Bragg were awarded the Nobel Prize in Physics in 1915.
William Henry Bragg was a professor of physics and mathematics, and was known for making important contributions to many scientific disciplines. Born in Westward, Cumberland in the United Kingdom on July 2, 1862, Bragg was thoroughly educated while attending Market Harborough Grammar School and King William's College in the Isle of Man. He later went on to study physics at the Cavendish Laboratory, as well as becoming elected to the Professorship of Mathematics and Physics at the University of Adelaide, in Southern Australia. Bragg's career continued to flourish, and he was subsequently appointed Cavendish Professor of Physics at Leeds, Quain Professor of Physics at the University College London, and Fullerian Professor of Chemistry at the Royal Institution.
Bragg had numerous research interests, but the work that earned him a rank as one the great leaders in science was his historic advancements in X-ray crystallography. Working with his son William Lawrence Bragg, he developed a method of bombarding single crystals with high-energy X-rays emitted by specially constructed vacuum tubes. When X-rays pass through the single crystal, they are diffracted according to a law discovered by the Braggs and are thus quantitatively deviated from their course. Patterns of diffracted X-rays can be imaged using photographic film, because the X-rays expose grains of silver bromide when they collide. By examining the pattern of X-rays diffracted by various crystals, Bragg and his son were able to establish some fundamental mathematical relationships between an atomic crystal structure and its diffraction pattern. For this achievement, William Henry Bragg and William Lawrence Bragg were awarded the Nobel Prize in Physics in 1915.
Bragg turned his attention to detection of sound in water during the First World War, and spent several years conducting research on the detection and measurement of sound with the intention of locating submarines. Following the war, Bragg was knighted and earned the Order of Merit in 1931. He was elected president of the Royal Society in 1935. His reputation earned Bragg honorary doctorate degrees from over 15 universities, and he was a distinguished member of many leading foreign science societies. Bragg was awarded the Royal Society's Rumford Medal in 1916 and the highest award, the Copley Medal in 1930. After a lifetime of achievement, Bragg died quietly on March 10, 1942.
John Frederick William Herschel (1792-1871) - John Herschel was the only child of renowned scientist and astronomer William Herschel. In 1820, the younger Herschel was one of the founding members of the Royal Astronomical Society, and when his father died in 1822 he carried on with the elder Herschel's work, making a detailed study of double stars. In collaboration with James South Herschel compiled a catalog of observations that was published in 1824. The work garnered the pair the Gold Medal from the Royal Astronomical Society and the Lalande Prize from the Paris Academy of Sciences. In 1839, Herschel developed a technique for creating photographs on sensitized paper, independently of William Fox Talbot, but did not attempt to commercialize the process. However, he published several papers on photographic processes and was the first to utilize the terms positive and negative in reference to photography.
William Herschel (1738-1822) - Friedrich William Herschel was an eighteenth century German astronomer who is credited with the discovery of the planet Uranus. In addition, Herschel measured the heights of about one hundred mountains on the moon, carefully recorded the data, and prepared papers that were presented to the Royal Society of London. In the late 1700s, he began to build and sell telescopes. The high quality of Herschel's optics was soon widely known outside of England, and he utilized them to publish three catalogues containing data on 2500 heavenly objects, including the sixth and seventh moons of Saturn, Enceladus and Mimas. Herschel continued making observations and cataloging his discoveries until his death in 1822 at age 84.
William Hyde Wollaston (1766-1828) - Although formally trained as a physician, Wollaston studied and made advances in many scientific fields, including chemistry, physics, botany, crystallography, optics, astronomy and mineralogy. He is particularly noted for originating several inventions in optics, including the Wollaston prism that is fundamentally important to interferometry and differential interference (DIC) contrast microscopy.
William Parsons Rosse (1800-1867) - Born William Parsons, Rosse was known as Lord Oxmantown before he became the third Earl of Rosse upon the death of his father in 1841. He served in a variety of political positions and was an avid astronomer. He is most famous for his construction of the largest and most powerful reflecting telescope in the Victorian period, which was frequently referred to as the Leviathan. The Leviathan's tremendous resolving power enabled Rosse, who was principally interested in nebulae, to make a number of astronomical discoveries and attracted scientists from around the world. It remained the world's largest telescope for almost 75 years and continued as the most powerful in terms of resolution for an even longer period of time. Dismantled in the early twentieth century, Rosse's telescope was restored in 1997 and is now part of a historic science center located at Birr.
William Rowan Hamilton (1805-1865) - Largely due to his important treatise on systems of rays, William Rowan Hamilton won the position of Royal Astronomer of Ireland while still an undergraduate at Trinity College, but it would be for his prediction of conical refraction that he would achieve even wider recognition in scientific circles. Hamilton later concentrated his efforts on the study of dynamics and produced several important papers in the field. Hamiltonian mechanics became appreciated as the discipline of quantum mechanics began to take shape in the twentieth century.
Zacharias Janssen (1580-1638) - Zacharias Janssen is generally believed to be the first investigator to invent the compound microscope. However, because the accomplishment is generally agreed among historians to be dated in the 1590s, most scholars believe that his father, Hans, must have played an important role in the creation of the instrument. The pair worked together as spectacle makers in Middleburg, Holland not far from Hans Lippershey, another optical scientist who is often alternatively credited with the invention of the microscope.
Étienne-Louis Malus (1775-1812) - In 1807, Malus commenced experiments on double refraction, the phenomenon that causes a light beam to divide into two orthogonal rays on passing through certain materials, such as Iceland spar. Malus's findings supported those obtained earlier by Dutch scientist Christiaan Huygens, whose description of double refraction was founded upon the then controversial idea that light is characteristically wavelike. In 1808, Malus discovered that light could be polarized (a term coined by Malus) by reflection as he observed sunlight reflected from the windows of the Luxemburg Palace in Paris through an Iceland spar crystal that he rotated.
Étienne-Jules Marey (1830-1904) - A French physiologist, Étienne-Jules Marey invented the photographic "gun", which was capable of taking 12 pictures per second and looked similar to a rifle. This instrument is commonly considered the first movie camera. Following the release of improved photographic film by George Eastman in 1885, Marey was able to vastly increase the photographic gun's exposure speed to 60 images per second, greatly improving the quality of his motion pictures and essentially laying the foundations of modern cinematography.