Patent ID: 7202926
Filing Date: 2007-04-10
Classification: G02B,G02F

Abstract:
1. A retardation optical element comprising a retardation layer having a cholesteric-regular molecular structure with liquid crystalline molecules in planar orientation, a helical pitch in the molecular structure being so adjusted that a wavelength of light selectively reflected by the retardation layer due to its molecular structure falls in a range shorter than a wave range of incident light to achieve smaller optical activity, wherein directions of directors of liquid crystalline molecules on one surface of two opposite main surfaces of the retardation layer are substantially the same, and those of directors of the liquid crystalline molecules on the other surface of the retardation layer are also substantially the same, and wherein the directions of the directors of the liquid crystalline molecules on the one surface of the retardation layer are substantially parallel with those of the directors of the liquid crystalline molecules on the other surface of the retardation layer.