Very few people realize that most great scientific discoveries are the result of advances in the measurement of light. But consider these developments: Nineteenth-century spectrometers revealed atoms' discrete spectra and led to quantum mechanics. The Michelson interferometer's optical-phase measurements laid the groundwork for special relativity. Microscopes have given us biology, and telescopes astronomy. Indeed, our most important source of information about our universe is light, and our ability to extract information from it is limited only by our ability to measure it...
At the same time, light is also a powerful practical tool in our kit of phenomena for the development of new life-enhancing and life-saving technologies, from medical diagnostics to telecommunications to next-generation computing to navigation (GPS). Again, our ability to utilize this wonderful tool is limited only by our ability to measure it.