A simple holographic technic for fabricating a LC/polymer switchable Fresnel lens

Abstract

In this article, we report on a novel technique for fabricating an electrically switchable Fresnel lens made from liquid-crystal–polymer composite. The Fresnel pattern is formed by means of interference between two planar and spherical wavefronts reflected from a single plano-convex lens. The simplicity of the procedure and capability to fabricate different focal lengths with the same arrangement are the unique advantages of this technique.

Phase Structure Recording in a Nematic Side-Chain Liquid-Crystalline Polymer

“…Various methods of producing lenses were reported for low molecular weight NLCs (including creation of polymer networks) [18][19][20][21][22][23][24][25]31,32] and amorphous polymers [26]. In this study, we applied the optical recording of the phase structures in the NLCP for the formation of negative and positive lenses.…”

“…In this case the steady-state inhomogeneous NLC structure reveals itself upon application of external ac field. This method was used to record conventional [18][19][20][21][22] and Fresnel [23][24][25] lenses. Phase structures, including microlens arrays [26], can be recorded in amorphous polymers.…”

53.3: A Shifting Holographic Fabrication for Switchable LC/Polymer Fresnel Lens

“…The ratio of TMPTA/NVP/S-271/NPG/RB is 63/24/10/2/1 by weight. And the refractive index of the cured polymer is 1.522 at 632.8 nm [8]. The applied LC is HCCH-03 with an ordinary refractive index of n o = 1.521, and an extraordinary refractive index of n e = 1.746.…”

Liquid crystal Fresnel zone lens based on single-side-patterned photoalignment layer

“…First, by exploiting striped electrodes to generate periodic electrical field distribution and locally control the directors of uniformly aligned LCs. [1] The second approach deals with direct guide the initial LC directors to realize periodic refractive index profile through patterned polymer relief [7,8] polymer dispersed liquid crystals [9,10], polymerstabilized liquid crystal [11,12], dye doped liquid crystals [13][14][15][16] and UV-modified alignment film [4,5] etc.…”