Optics and photonics are technical enablers for many areas of the economy, and dramatic technical advances have had a major impact on daily life. For example, in the last decade, advances in optical fiber communications have permitted a nearly 100-fold increase in the amount of information that can be transmitted from place to place, enabling a society-transforming Internet to thrive. As noted in the introduction to Charles Kao’s 2009 Nobel Prize lecture on his work in optical fiber communications, “the work has fundamentally transformed the way we live our daily lives.”1 Indeed, optical fiber communications have enabled what Thomas Friedman has called a “flat world.”2 Without optics, the Internet as we know it would not exist.
The phrase “optics and photonics” is used throughout this study to capture light’s dual nature (1) as a propagating wave, like a radio wave, but with a frequency that is now a million times higher than that of a radio wave; and (2) as a collection of traveling particles called photons, with potential as a transformative field similar in impact to electronics. Further proof that optics and photonics are technical enablers can be seen in the laser. A laser provides a source of light that can be (1) coherent, meaning that a group of photons can act as a single unit; and
1 Kao, C.K. “Sand from Centuries Past: Send Future Voices Fast.” Nobel Lecture. 2009. Available at http://www.nobelprize.org/nobel_prizes/physics/laureates/2009/kao_lecture.pdf. Accessed July 30, 2012.
2 Friedman, T.L. 2005. The World Is Flat. New York, N.Y.: Farrar, Straus, and Giroux.
(2) monochromatic, meaning that the photons can have a well-defined single color. Today we can see how these effects are used in many areas. With light:
• High amounts of energy can be precisely directed with low loss.
• Many different properties of waves (i.e., degrees of freedom such as amplitude, frequency, phase, polarization, and direction) can be accurately manipulated.
• Waves can be coherently processed to have high directionality, speed, and dynamic range.
Optics, Electro-optics, Optoelectronics, and Photonics: Definitions and the Emergence of a Field
Optics—the science that deals with the generation and propagation of light—can be traced to 17th-century ideas of Descartes concerning transmission of light through the aether, Snell’s law of refraction, and Fermat’s principle of least time. These ideas were subsequently built upon through the 19th century by Hooke (interference of light and wave theory of light), Boyle (interference of light), Grimaldi (diffraction), Huygens (light polarization), Newton (corpuscular theory), Young (interference), Fresnel (diffraction), Rayleigh, Kirchhoff, and, of course, Maxwell (electromagnetic fields). The end of the 19th century marked the close of the era of classical optics and the start of quantum optics. In 1900, Max Planck’s introduction of energy quanta marked the first steps toward quantum theory and an early understanding of atoms and molecules. With the demonstration in 1960 of the first laser, many of the fundamental and seemingly disconnected principles of optics established by Einstein, Bose, Wood, and many others were focused and drawn together.
“Electro-optics” and “optoelectronics” are both terms describing subfields of optics involving the interaction between light and electrical fields. Although John Kerr, who discovered in 1875 that the refractive index of materials changes in response to an electrical field, could arguably be regarded as the inaugurator of the field of electro-optics, the term “electro-optics” first gained popularity in the literature in the early 1960s. By 1964 authors from RAND could be found publishing from a group called the Electro-Optical Group. In 1965 the Quantum Electronics Council of the Institute of Electrical and Electronics Engineers (IEEE) was formed from IEEE’s Electronic Devices Group and Microwave Theory and Techniques Group; in 1977 became an IEEE society; and in 1985 took the name Lasers and Electro-Optics Society, thus legitimizing the use of the name in the professional field.
The exact origins and limits of the term “optoelectronics” are difficult to pin down. Some claim that optoelectronics is a subfield of electro-optics involving the study and application of electronic devices that source, detect, and control light. Colloquially, the term “optoelectronics” is most commonly used to refer to the quantum mechanical effects of light on semiconductor materials, sometimes in the presence of an electrical field. Semiconductors started to assume serious importance in optics in 1953, when McKay and McAfee demonstrated electron multiplication
Although the fields of optics and photonics have developed gradually (Box 1.1), important changes have occurred over the past several years that merit study and related action:
1. The science and engineering of light have enabled dramatic technical advances.
2. Globalization of manufacturing and innovation has accelerated.
in silicon and germanium p-n junctions, and Neumann indicated separately in a letter to a colleague that that one could obtain radiation amplification by stimulated emission in semiconductors. Japan’s Optoelectronics Industry and Technology Development Association was established in 1980, and the U.S. counterpart is the Optoelectronics Industry Development Association.
As used in its present sense, the term “photonics” appeared as “la photonique” in a 1973 article by French physicist Pierre Aigrain. The term began to be seen in print in English around 1981 in press releases, annual reports of Bell Laboratories, and internal publications of Hughes Aircraft Corporation and in the more general press. In 1982, the trade magazine Optical Spectra changed its name to Photonics Spectra, and in 1995 the International Society for Optics and Photonics (SPIE) debuted Photonics West, arguably one of the largest conferences in optics and photonics. Sternberg defines “photonics” as the “engineering applications of light,” involving the use of light to detect, transmit, store, and process information; to capture and display images; and to generate energy. However, in the professional literature, “photonics” is used almost synonymously with the term “optics,” referring equally to both science and applications. The term “photonics” continues to gain popularity today. In 2006 Nature Publishing Group established the journal Nature Photonics, and in 2008 the Lasers and Electro-Optics Society became the IEEE Photonics Society.
Brown, R.G.W., and E.R. Pike. 1995. A history of optical and optoelectronic physics in the twentieth century. In Twentieth Century Physics, Vol. III, L.M. Brown, A. Pais, and B. Pippard, eds. Bristol, U.K., and Philadelphia, Pa.: Institute of Physics Publishing; New York, N.Y.: American Institute of Physics Press.
IEEE Global History Network. 2012. “IEEE Photonics Society History.” Available at http://www.ieeeghn.org/wiki/index.php/IEEE_Photonics_Society_History. Accessed August 1, 2012.
Nature Publishing Group. 2006. “Nature Publishing Group Announces the Launch of Nature Photonics.” Available at http://www.nature.com/press_releases/Nature_Photonics_launches.pdf. Accessed August 1, 2012.
SPIE. 2011. “History of the Society.” Available at http://spie.org/x1160.xml. Accessed August 3, 2012.
Sternberg, E. 1992. Photonic Technology and Industrial Policy: U.S. Responses to Technological Change. Albany, N.Y.: State University of New York Press.
3. Optics and photonics have become established as enabling technologies for a multitude of industries that are vital to our nation’s future.
Accordingly, the National Research Council’s Committee on Harnessing Light: Capitalizing on Optical Science Trends and Challenges for Future Research undertook a new study to examine the current state of the art and economic impact of optics and photonics technologies, with an eye toward ensuring that optics and photonics continue to enable a vibrant and secure future for U.S. society.
Optics and photonics, an enabling technology with widespread impact, exhibits the characteristics of a general-purpose technology, that is, a technology in which advances foster innovations across a broad spectrum of applications in a diverse array of economic sectors. Improvements in those sectors in turn increase the demand for the technology itself, which makes it worthwhile to invest further in improving the technology, thus sustaining growth for the economy as a whole. The transistor and integrated circuit are good examples of general-purpose technologies. The importance of photonics as an enabling technology since 1998 can be highlighted by a few examples:
• A cell phone can enable video chats and perform an Internet search, with optics and photonics playing a key part. The most obvious contribution of optics is the high-resolution display and the camera. In addition, the cell phone uses a wireless radio connection to a local cell tower, and the signal is converted to an optical data stream for transmission along a fiber-optic network. An Internet search conducted on the phone will be directed over these fibers to a data center, and in a given data center clusters of co-located computers talk to each other through high-capacity optical cables. There can be more than 1 million lasers involved in the signaling.
• People are surrounded by objects whose manufacture was enabled by highly accurate directed-energy light. For example, nearly every microprocessor has been fabricated using optical lithographic techniques, and in nearly all advanced manufacturing, high-power lasers are used for cutting and welding.
• Optics is rapidly changing medical imaging, making it possible not only to see with higher resolution inside the body but also to distinguish between subtle differences in biological material. Swallowed capsules can travel through the body and send images back to a doctor for diagnosis. Today, the relatively young field of optical coherence tomography has the potential
to save thousands of lives annually3 by providing dramatically better images for early detection of disease. Optical spectroscopic techniques can provide valuable information from blood and tissue samples that is critical in early detection and prevention of health problems, and eye, dental, and brain surgery now uses focused lasers for ablating, cutting, vaporizing, and suturing.
• In World War II, only a small fraction of the bombs dropped from airplanes hit their target. “Smart” bombs debuted in Vietnam. Although the Thanh Hoa Bridge withstood 871 sorties by conventional bombs and 11 U.S. planes were lost, the bridge was destroyed with four sorties and no losses the first time smart bombs were used. In Iraq and Afghanistan, smart bombs are the norm.4 The critical advance is accurate targeting using laser designators and laser-guided munitions. Moreover, situational awareness of the battlefield and of enemy terrain provides information for targeting. Imaging systems using LIDAR (light detection and ranging), such as HALOE, can provide wide-area three-dimensional imaging. Even wider-area passive sensors such as ARGUS-IS can provide highly detailed mapping of a country in days as opposed to months.
Additional examples of optics and photonics as enabling technologies are discussed in subsequent chapters and also in Appendix C.
From an economic standpoint, an enabling technology like optics and photonics tends to be commercialized outside the industry, and profits can be generated by companies that do not consider themselves a part of the photonics industry. These companies are more inclined to invest in previously validated applications for which photonics can but does not necessarily provide the sole technology solution, rather than to invest in photonics in particular. Since 2000, the photonics industry has tended to receive little interest from the investment community and little financial analyst coverage, and start-up companies in photonics can have difficulty acquiring seed capital.5
However, a large fraction of the major companies in the United States rely on
3 Center for Integration of Medicine and Innovative Technology. Capabilities brochure. Available at http://www.cimit.org/images/media_center/CapabilitiesBrochure.pdf. Accessed July 30, 2012.
4 Air University Review. 1987. “The Decisive Use of Air Power?” Available at http://www.airpower.maxwell.af.mil/airchronicles/aureview/1987/werrell.xhtml. Accessed July 30, 2012.
photonics-enabled technologies to be competitive in the marketplace.6 To move forward in general, having an optics and photonics technology roadmap that focuses on meeting needs in specific market applications and that is synergistic with business and marketing trends could help to improve business development, profitability, and growth.
In considering actions for global leadership in the photonics industry, the committee took note of several important points. For example, although many key optics and photonics innovations occurred in the United States, including in display and communications technologies, the multibillion-dollar display industry has moved mostly to Southeast Asia, with a negligible fraction of display production remaining in the United States. Furthermore, whereas the United States for decades led the manufacture of telecommunications equipment, China went from having no company in 1998 in the top 10 largest telecommunications companies in the world to having three such companies in 2011. A similar scenario exists for Chinese companies that specialize in selling optical components and subsystems. By contrast, data centers continue to be located overwhelmingly in the United States, possibly because the United States has the most effective communications infrastructure at the moment.
A theme evident in several of the presentations made to the committee was that innovation will remain critical to ensuring a U.S. leadership position in optics and photonics. The United States has acclaimed educational institutions and a creative, entrepreneurial corporate spirit. According to the U.S. Patent and Trademark Office, the number of patents granted to the United States in 2010 in the field of optics was more than 50 percent greater than that granted to the next-nearest country. Yet, according to the records of the Optical Society of America, the number of research papers submitted to its journals in 2010 by scholars from the Pacific Rim countries exceeded the number of papers submitted by North American authors.7
Education plays a critically important role in ensuring a vibrant future for the United States in the fields of optics and photonics. Today, the United States has
6 See, for example, the National Center for Optics and Photonics Education’s (OPTEC’s) Photonics: An Enabling Technology, for fields that are important. Available at http://www.op-tec.org/pdf/Enabling_Technology_9NOV2011.pdf. Accessed July 30, 2012.
7 Cao, J. 2012. A new journal in optics and photonics—Light: Science and Applications. Editorial. Light: Science and Applications 1:Online. Available at http://126.96.36.199/lsa/journal/v1/n3/full/lsa20123a.xhtml. Accessed July 26, 2012.
many outstanding universities that educate students from around the world in the classroom and in research laboratories. Over the past several years, many institutions outside the United States have also invested heavily in excellent educational facilities. Because education is inextricably linked to innovation in optics and photonics, the committee underscores the importance to the nation of maintaining a strong U.S. educational infrastructure in optics and photonics. Although the present study does not focus on education, it does mention specific examples that might benefit from action, including the training of skilled technicians as well as ensuring that an adequate numbers of citizens can be hired by the defense industry. The committee concluded that improvements in technical education are needed to increase the quality of skilled blue-collar workers in optics and photonics.
Although many of the innovations in optics and photonics (i.e., the science and engineering of optical waves and photons) have occurred in the United States, U.S. leadership is far from secure. The committee has heard compelling arguments that, if the United States does not act with strategic vision, future scientific advances and economic benefits might be led by others.
It is the committee’s hope that this study will help policy makers and leaders decide on courses of action that can advance the future of optics and photonics; promote a greener, healthier, and more productive society; and ensure a leadership position for the United States in the face of increasing foreign competition.
In general, the committee’s recommendations call for improved management of U.S. public and private research and development resources, emphasizing the need for public policy that encourages adoption of a portfolio approach to investing in the wide and diverse opportunities now presented by optics and photonics.