Dr. Gary Eden, University of Illinois Micro-Cavity Arrays: Lighting the Way to the Future (2005-present) A research team funded by AFOSR has pioneered the use of micro-plasmas in a revolutionary approach to illumination, and Drs. Gary Eden and Sung-Jin Park of the University of Illinois, UrbanaChampaign, have founded Eden Park Illumination, Inc. to bring this new lighting technology to the world. Just as in a fluorescent light, a micro-cavity array is energized by an applied voltage. By successfully confining that plasma in parallel rows of micro-cavities within thin sheet materials, Eden and Park ultimately arrived at various implementations of micro-plasma arrays, some of which result in inexpensive, wafer-thin, and very flexible sheets of light. The key to these light arrays are the microcavities that are formed within the flexible sheets. In one of the most important implementations, the one being developed by Eden Park Illumination, a sheet of aluminum foil is placed in an anodizing bath. By controlling the bath parameters, its temperature, and the time of anodizing, large arrays of micro-cavities can be formed with near optimum shape and with automatically placed interconnecting aluminum electrodes. The largest array thus far contains a quarter-million luminous micro-cavities. When A/C power is supplied through the almost invisible grid, the array bursts to life. The microcavity arrays (MCAs) are ruggedized to a certain extent and have an ultimate thickness of about 4 millimeters, leaving a wafer that weighs less than 200 grams. This revolutionary advance in lighting offers many advantages: the array is thin, flat, and small – a major contributor to efficiency; the fluorescent light tube has a stated efficiency of about 75 to 80 lumens per watt – by comparison, the efficiency of the MCA is over 90 percent; and the MCA does not contain mercury – an environmental advantage. In addition, the array is fully dimmable while fluorescent lighting is not. The MCA also offers better color rendering, its components are fully recyclable, and it lasts up to 20,000 hours before failure. While the MCA is currently not as efficient as an LED, it runs much cooler and is far lighter. Special applications might include aircraft cockpit lighting and displays due to less weight, size, and heat, as well as the flexibility to conform to cramped interior spaces. Tanks and other combat vehicles would offer an ideal application. Interior lighting for homes and offices could be transformed given the flexibility of the technology. Even the lowly refrigerator light could be in line for an upgrade. AFOSR Program Manager Dr. Howard Schlossberg has funded Eden’s MCA work since 2005.112
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“My students and I owe a great debt to AFOSR. Because of continuous support from Dr. Howard Schlossberg of AFOSR, for the past 34 years, we have been able to pursue research avenues in lasers and plasmas that defy quick solutions and yet have considerable promise for DoD and commercial applications. As a result, 44 individuals have received the Ph.D. degree with AFOSR support and many have made enormous contributions to military systems, commercial products, and advances in research. Companies have been formed that now manufacture lighting and water purification systems that have not existed in the past. The sustained support of AFOSR for investigators throughout this country is a crucial factor in the discovery and development of technologies that undergird the force capabilities of the DoD but also serve as the basis of entirely new products and industries that provide the future for the U.S. economy. Congratulations, AFOSR, on your 60th birthday! My deepest thanks for your support and my hope is that the next 60 years are as productive, and beneficial for our country, as have the first six decades.”