Optics – A Science as Old as Mankind
Optics is the science that studies the nature, properties and applications of light.
Light and color have fascinated the mankind from its early beginnings, for a very simple reason: the intimate link between light and our sense of sight makes optics phenomena visually reach and, often, eye pleasing. We see the world through one of the most exquisite optical instruments of all: the human eye. One does not need a Ph.D. in Science to gaze in wonder at a rainbow, or to enjoy the light and colors of a beautiful sunset.
The nature of light has intrigued the brightest minds from early ages to modern day era. From the first looking glasses alluded to in the Exodus to modern era night vision goggles, from early mirrors uncovered in ancient Egypt to the 2.4 meter-diameter hyperboloidal primary mirror of the Hubble Space Telescope, from Leonardo da Vinci’s Camera Obscura (the first pinhole camera) to the modern digital cameras, the history of human kind is dotted with attempts to understand light, control it and use it to better human lives. The first whirlwind of accomplishments in Optics occurred in the seventeenth century starting with the invention of the refractive telescope and of the compound microscope. During the course of the next 350 years, the field of Optics has evolved and advanced at an ever increasing pace. Great advances have been made in the application of Optics in various fields of human activity, and our fundamental theoretical understanding of light has advanced tremendously during that time, laying the foundation for even greater things to come and opening the door to a genuine explosion in the practical applications of light and Optics.
Photonics: The Science of Harnessing Light
It was the development of the laser in the 1960’s and of the low-loss optical fibers that placed Optics at the center of the next technological revolution, and opened the door of a new age in technology: the age of Photonics.
The inventions of the laser and optical fibers have meant for Optics what the invention of the transistor and integrated circuits have meant for Electronics. Indeed, the invention of the transistor in 1948 has paved the way for the microelectronics industry and thus has opened the door to the computer age, making electronics a pervasive presence and changing our lives in more ways than one could have predicted or even imagined. In much the same way, the invention of the laser, coupled with the development of low-loss optical fibers, has ignited an explosion in the field of optical communication, and, along the way, has created more and far-reaching applications for light than anyone could have imagined.
The word Photonics was coined in the late 1960’s to describe a research field whose primary goal at the time was to use light (either visible or infrared) to performs functions that traditionally used to fall within the typical domain of electronics, such as telecommunications, remote sensing, control, information processing and the like. Since light is made up of photons – the fundamental particle of light and a fundamental building block of the universe – the word photonics was born, in a similar way that the word “electronics” is derived from electron, the fundamental particle and quanta of electric charge. At a component and system level then, photonics describes components and systems that operate with photons –particles of light- much in the same way that the word “electronics” describes components and systems that operate with electrons.
One should note that photonics is not a technology to (completely) replace electronics; rather, the two work hand-in-hand: photonics benefits greatly from the advancements in electronics, and electronics growth along with photonics. In fact, there is a significant and increasing overlap between the two fields, in what traditionally has been called opto-electronics. The sophisticated combination of light and electricity has created synergies that no one could have envisioned when the term photonics was coined. There is also no clear-cut distinction between the terms Optics, Photonics, and Optoelectronics, in their most general sense, particularly at the applications level. Increasingly, the word photonics is used where traditionally the terms Optics and/or Optoelectronics have been used in the past.
According to the Photonics Dictionary, published by Laurin Publishing – an authoritative source in the field – “Photonics is the technology of generating and harnessing light and other forms of radiant energy whose quantum unit is the photon. The science includes light emission, transmission, deflection, amplification and detection by lasers and other light sources, optical components and instruments, fiber optics, electro-optical instrumentation, related hardware and electronics, and sophisticated systems. The range of applications of photonics extends from energy generation to detection to communications and information processing.”
Many science fields come together in conceiving, designing, developing and bringing into being the materials, devices and systems able to perform the functions described in the above definition of photonics. As such, photonics is an interdisciplinary field across such diverse fields as optics, physics, electrical engineering, chemistry, materials science, and more. If one adds the actual applications of photonics, the field touches practically every aspect of human life, and the possibilities for growth are endless.
Optics and Photonics – The Technology of the 21st Century
Whereas the enabling technology of the 20th century was undoubtedly electronics, the 21st century is predicted to become the century of photonics. The economic implications are far reaching, and entities as large as whole continents or countries, or as small as universities, schools and start-up companies try to position themselves in a leading role, at their respective levels, in the development and implementation of the new technology. As a measure of the significance and impact of this new technology at all society levels, one should note that both the United States and the European Union have commissioned their own separate expert groups to conduct thorough assessments of the broad field of Optics and Photonics Science and Engineering, and come up with recommendations aimed at positioning themselves in leading roles and maximizing the benefits of the new technology to the society. Both reports have identified Photonics (Optics) Science and Engineering as an area vital to their national interest s.
The 1999 report “Harnessing Light: Optical Science and Engineering for the 21st Century” prepared by the United States National Research Council (the principal operating agency of the National Academy of Science, National Academy of Engineering and Institute of Medicine) was the product of an unprecedented effort to “bring together all aspects of the field of optics in one assessment organized around national needs”. The report recognizes optics (in its broadest sense) as an enabling technology pervasive in modern life, and identifies seven major areas of national interest that optics (photonics) enables:
- Information Technology and Telecommunications
- Health Care and the Life Sciences – Biophotonics
- Optical Sensing, Lighting, and Energy
- Optics in Manufacturing
- National Defense
- Manufacturing of Optical Systems and Components
- Education and Research
The content of this page was prepared by Dr. Corneliu Rablau, Associate Professor of Physics at Kettering University, Director of the Photonics and Fiber Optics Lab.