{"40455":{"#nid":"40455","#data":{"type":"news","title":"Scientists Develop Focus-Changing Eyeglass Lenses","body":[{"value":"\u003Cp\u003EOptical scientists at The University of Arizona and the Georgia Institute of Technology have developed new switchable, flat, liquid crystal diffractive lenses that can adaptively change their focusing power.\u003C\/p\u003E\n\u003Cp\u003EThat\u0027s great news for those old enough to wear bifocals.\u003Cbr \/\u003E\nAnd it\u0027s great news for anyone with imperfect vision, for it opens the wayfor next-generation \u0022smart\u0022 eyeglasses -- glasses with built-in automatic focus. \n\u003C\/p\u003E\n\u003Cp\u003EIn the foreseeable future, for example, you won\u0027t change prescription eyeglasses -- your eye doctor will just tweak a new prescription into the specs you already own.\n\u003C\/p\u003E\n\u003Cp\u003EYou could even program your glasses for better than 20-20 vision.\n\u003C\/p\u003E\n\u003Cp\u003E\u0022Right now, in our prototype, you switch the lenses on or off to change focus,\u0022 said Nasser Peyghambarian, chair of photonics and lasers in UA\u0027s College of Optical Sciences and professor of optical sciences, materials science and engineering. \u0022But ultimately this will act just like your automatic camera: Eyeglass lenses will know where to focus just like your auto-focusing camera does.\u0022\n\u003C\/p\u003E\n\u003Cp\u003EPeyghambarian is part of the team that began developing the focus-changing lenses in 2001 under an agreement between the university and private industry. The UA licensed three patents from the work to the Johnson and Johnson Development Corp., which sponsored the research. A firm called Pixel Optics has since purchased the patent licenses from Johnson and Johnson to commercialize the innovative technology.\n\u003C\/p\u003E\n\u003Cp\u003ETen UA scientists and two colleagues now at the Georgia Institute of Technology are publishing their first science paper about the switchable-focus lenses this week in an article online at the Proceedings of the National Academy of Sciences website, \u003Ca href=\u0022http:\/\/www.pnas.org\/current\/shtml\u0022 title=\u0022http:\/\/www.pnas.org\/current\/shtml\u0022\u003Ehttp:\/\/www.pnas.org\/current\/shtml\u003C\/a\u003E.\n\u003C\/p\u003E\n\u003Cp\u003E\u0022It\u0027s great to see our new concept materialize and be validated after all these years of continuous efforts,\u0022 said Bernard Kippelen. Kippelen, who helped start the project when he was at the UA, is now a professor of electrical and computer engineering and associate director of the Center for Organic Photonics and Electronics at Georgia Tech.\n\u003C\/p\u003E\n\u003Cp\u003EThe novel lenses focus electroactively, said Guoqiang Li, UA optical sciences assistant research professor and lead author on the scientific paper. \n\u003C\/p\u003E\n\u003Cp\u003EThey are basically two pieces of flat glass spaced five microns apart. Five microns is an incredibly small space -- roughly one-twentieth the diameter of a human hair. The space is filled with liquid crystal -- the same kind of stuff in your laptop\u0027s liquid crystal display.\n\u003C\/p\u003E\n\u003Cp\u003EThe flat glass is coated with an even thinner layer (one-tenth micron) of indium tin oxide, or ITO, which is a transparent electrode. Unlike electrodes made of aluminum or gold, ITO transmits most of the light that hits it. \n\u003C\/p\u003E\n\u003Cp\u003EThe transparent electrodes are patterned in a circular array over the area of the lens. The circular pattern is created through photolithography, an extremely precise technique that processes with light and chemicals.\n\u003C\/p\u003E\n\u003Cp\u003EApplying less than two volts to the circuit changes the orientation of the liquid crystal molecules, and that changes the optical path length through the lens. It takes only about 1.8 volts to change the index of refraction so that light refocuses, Peyghambarian and Li explained. The result is a flat piece of glass that acts like a lens.\n\u003C\/p\u003E\n\u003Cp\u003EThe scientists first tested the imaging properties of the lens on a model human eye, then built prototype eyeglasses that real humans tested. The clinical results agreed with the model eye test.\n\u003C\/p\u003E\n\u003Cp\u003ETheir tests showed that distance vision was no way impaired when the glasses were switched off and enabled close-up vision when switched on.\n\u003C\/p\u003E\n\u003Cp\u003E\u0022We have demonstrated switchable liquid crystal diffractive lenses with high diffraction efficiency, high optical quality, rapid response time, and diffraction limited performance,\u0022 they reported in the PNAS article. \u0022These flat lenses are highly promising to replace conventional area division refractive, multi-focal spectacle lenses used by presbyopes,\u0022 they report.\n\u003C\/p\u003E\n\u003Cp\u003EEstimates are that 93 percent of the world\u0027s population over age 45 have the condition called \u0022presbyopia,\u0022 where an aging person\u0027s eye lens loses flexibility and therefore, its ability to shift focus from distant to near objects.\n\u003C\/p\u003E\n\u003Cp\u003EPresbyopes will be some of the first to benefit from the UA research.\n\u003C\/p\u003E\n\u003Cp\u003EElectroactively focusing eyeglasses will revolutionize the $50 billion worldwide vision care industry, backers said at the outset of the UA research project. \n\u003C\/p\u003E\n\u003Cp\u003ETheir major step in creating state-of-the-art liquid crystal diffractive lenses will have applications beyond vision care, the scientists predict. Tools with switchable lens elements would be valuable in dentistry, for example.\n\u003C\/p\u003E\n\u003Cp\u003E\u0022People don\u0027t often recognize that university scientists make prototypes,\u0022 Peyghambarin said. \u0022People think of us as just generating science papers. But when we actually make something like this, in house, people begin to realize we have real expertise that\u0027s applicable to everyday problems.\u0022\n\u003C\/p\u003E\n\u003Cp\u003EIn addition to Li and Peyghambarian, UA optical scientists who collaborated in the research are David L. Mathine, Pouria Valley, Pekka Ayras, M. S. Giridhar, Gregory Williby, James Schwiegerling (who also is on the faculty in UA\u0027s department of ophthalmology and vision sciences), Gerald R. Meredith, and Seppo Honkanen. Bernard Kippelen and Joshua N. Haddock of the Georgia Institute Technology also collaborated. \n\u003C\/p\u003E\n\u003Cp\u003EWritten by Lori Stiles, University of Arizona.\n\u003C\/p\u003E\n\u003Cp\u003E\u003C\/p\u003E\n\u003Cp\u003E\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"Scientists at Georgia Tech and the University of Arizona have developed eyeglass lenses that can change focus. The lenses could replace bifocals and lead to programmable eyeglasses.","format":"limited_html"}],"field_summary_sentence":[{"value":"Programmable lenses could replace bifocals"}],"uid":"27310","created_gmt":"2006-04-05 00:00:00","changed_gmt":"2016-10-08 03:00:55","author":"David Terraso","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2006-04-05T00:00:00-04:00","iso_date":"2006-04-05T00:00:00-04:00","tz":"America\/New_York"},"extras":[],"hg_media":{"40456":{"id":"40456","type":"image","title":"Focus-changing lenses","body":null,"created":"1449174200","gmt_created":"2015-12-03 20:23:20","changed":"1475894191","gmt_changed":"2016-10-08 02:36:31","alt":"Focus-changing lenses","file":{"fid":"189441","name":"tgs57814.jpg","image_path":"\/sites\/default\/files\/images\/tgs57814.jpg","image_full_path":"http:\/\/www.tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/tgs57814.jpg","mime":"image\/jpeg","size":1067720,"path_740":"http:\/\/www.tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/tgs57814.jpg?itok=O3NQJJJs"}}},"media_ids":["40456"],"related_links":[{"url":"http:\/\/www.ece.gatech.edu\/faculty\/fac_profiles\/bio.php?empno=517632","title":"Bernard Kippelen"}],"groups":[{"id":"1183","name":"Home"}],"categories":[{"id":"135","name":"Research"}],"keywords":[{"id":"2943","name":"eyeglasses"},{"id":"2944","name":"glasses"},{"id":"2942","name":"Kippelen"},{"id":"2945","name":"lens"},{"id":"2946","name":"lenses"},{"id":"2768","name":"optics"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cp\u003E\u003Cstrong\u003EGeorgia Tech Media Relations\u003C\/strong\u003E\u003Cbr \/\u003ELaura Diamond\u003Cbr \/\u003E\u003Ca href=\u0022mailto:laura.diamond@comm.gatech.edu\u0022\u003Elaura.diamond@comm.gatech.edu\u003C\/a\u003E\u003Cbr \/\u003E404-894-6016\u003Cbr \/\u003EJason Maderer\u003Cbr \/\u003E\u003Ca href=\u0022mailto:maderer@gatech.edu\u0022\u003Emaderer@gatech.edu\u003C\/a\u003E\u003Cbr \/\u003E404-660-2926\u003C\/p\u003E","format":"limited_html"}],"email":["david.terraso@comm.gatech.edu"],"slides":[],"orientation":[],"userdata":""}}}