Asymmetric tunable Fabry-Perot cavity using switchable polymer stabilized cholesteric liquid crystal optical Bragg mirror

Kedar Sathaye (1) , Laurent Dupont (1) , Jean-Louis de Bougrenet de La Tocnaye (1)

1 OPT - Département Optique

Optical properties of an asymmetric Fabry-Perot (FP) cavity interferometer made up of a conventional metallic mirror and a polymer stabilized cholesteric liquid crystal (PSCLC) Bragg mirror have been investigated. The first FP cavity design comprises a gold mirror, an isotropic layer made up of the polymer glue, a quarter wave plate to convert the input linearly polarized modes into the circularly polarized modes inside the cavity, and the PSCLC Bragg mirror, all sandwiched between two indium tin oxide glass plates. The second FP cavity has a layer of conducting polymer deposited on the quarter-wave plate to apply the electric field only to the cholesteric stack. To have reflectivity above 95% in visible range we implement 30 layers of cholesteric liquid crystal in a planar Grandjean texture. The device compactness and the mirror parallelism due to the monolithic fabrication of FP are advantageous from the technical point of view. We test the FP tunability by shifting the resonance wavelength through an entire period; by applying electric field and/or by varying the temperature.

Mots clés: Liquid crystal device; Cholesteric; Filters

Domaines: Optique / photonique

Kedar Sathaye, Laurent Dupont, Jean-Louis de Bougrenet de La Tocnaye. Asymmetric tunable Fabry-Perot cavity using switchable polymer stabilized cholesteric liquid crystal optical Bragg mirror. Optical Engineering, 2012, 51 (3), pp.034001-1-034001-7. ⟨hal-00703660⟩