LIQUID-CRYSTAL LENSES

Abstract

BIFOCAL LENSES AND THE dizziness anddisoemfort that come from gazing through them could become a thing of the past, thanks to new liquid-crystal lenses that quickly switch between corrective states (Proc. Natl. Acad. Set. USA, published online April 5, dx.doi.org/10.1073/ pnas.0600850 103). Because lenses made with nematic liquid crystals can easily change their focusing power, optics researchers have eagerly eyed them as potential replacements for multifocal lenses. But these efforts have been hamstrung by slow response times associated with the relatively thick layers of liquid crystal required. Now, a group led by University of Arizona optical scientists Guoqiang Li and Nasser Peyghambarian have come up with a lens design that uses a liquid-crystal layer just 5 ice thick. Prototype spectacles made with these lenses can change focus in less than a second and require only low voltage. The lens design features a liquid- crystal layer sandwiched between two thin sheets of glass. Tiny electrodes photolithog...