Electrically switchable mirrors based on polymer-stabilized cholesteric liquid crystals

Abstract

We developed an electrically switchable mirror based on polymer-stabilized, short-pitched cholesteric liquid crystals using electro-optical cells with planar alignment. The devices enable the switching of a pre-selected reflective wavelength of the cholesteric to reflect a different wavelength in corresponding to the magnitude of applied electric field. The principle of the wavelength shift to a shorter wavelength is a result of field-induced pitch shortening near the boundaries. The spectral wavelength shift of the reflected wavelength is about 140-nm and the wavelength shift is linearly proportional to the magnitude of applied voltage. The optical response of the device is also studied.