Tunable Fresnel lens using nanoscale polymer-dispersed liquid crystals
نویسندگان
چکیده
An electrically tunable Fresnel zone plate lens is demonstrated using nanoscale polymer-dispersed liquid crystal droplets. In the voltage-off state, the zone plate behaves like a positive lens. The measured diffraction efficiency is close to the theoretical limit and is controllable by voltage. The major advantages of such a Fresnel lens are simple fabrication, large aperture size, polarization independent, and fast switching speed, although the required operating voltage is relatively high. © 2003 American Institute of Physics. @DOI: 10.1063/1.1604943#
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