Switchable reflective lens based on cholesteric liquid crystal.

We demonstrated a switchable reflective lens based on choleteric liquid crystal (CLC) with a plano-convex shape. The plano-convex CLC lens was fabricated by assembling a planar substrate and a concave substrate. The reflective CLC lens exhibits wavelength selectivity and handedness sensitivity like the conventional CLC cell. The plano-convex CLC lens acts as a biconvex lens with the same curvature due to the Bragg reflection of the CLC layer. In addition, the reflective CLC lens was defocused by applying external voltage.