Patent ID: 6900469
Filing Date: 2005-05-31
Classification: G02F

Abstract:
1. A liquid crystal display element comprising a pair of substrates, a liquid crystal layer being provided between the substrates, and a visible light absorbing layer on a reverse surface of one of the substrates, the liquid crystal layer containing a liquid crystal composition that exhibits a cholesteric phase, the liquid crystal display element being driven by application of a voltage to the liquid crystal layer, the liquid crystal display being a reflective type liquid crystal display in which visible light of a particular wavelength is selectively reflected by changing the liquid crystal between focal conic and planar bistability states to form a display, wherein: the liquid crystal composition contains a mixture of a chiral material and nematic liquid crystal; a viscosity a [cP] of the liquid crystal composition is in a range from 30 to 150; a dielectric anisotropy b of the liquid crystal composition is in a range from 5 to 50; a thickness c [μm] of the liquid crystal layer is in a range from 3 to 8; and a product of a, b, and c is not less than 3500, wherein the liquid crystal display element is adapted to exhibit a stable focal conic state.