Optical Properties of Single Layer Non-Absorptive Broadband CLC Polarizers

Abstract

Abstract We report for the first time the results of theoretical study on the optical properties of single layer non-absorptive broadband cholesteric liquid crystals (BBCLC) polarizers. The objective of this study is to understand the effect of material parameters and sample configuration on the performake of BBCLC films and therefore provide guidance for the fabrication of high quality single layer broadband polarizers. The study is based on Berreman's 4×4 matrix formalism. Nonlinear pitch distribution across the cell thickness is used in the simulation. Pitch gradient smaller than 20nm/μm is found necessary for high extinction ratio for chosen material system. The extinction ratio decreases significantly when the incident angle (internal angle) is greater than 20° and an extinction revere region is found in the case of large angle of incidence. The theoretical results are compared with the experimental results of Reveo's broadband polarizers and show reasonably good agreement.