Patent ID: 6496241
Filing Date: 2002-12-17
Classification: G02F

Abstract:
A liquid crystal device comprising:a layer of twisted liquid crystal having a first surface director orientation oriented in a first direction at a first surface of the layer and a second surface director orientation oriented in a second direction at a second surface of the layer, the first direction being different from and non-perpendicular to the second direction; a retarder arranged immediately adjacent the layer to compensate for a residual retardation of the layer with a first finite applied field across the layer, the retarder having an optic axis which is substantially parallel or perpendicular to the bisectrix of the first and second directions; and a reflector for reflecting light transmitted through the layer, wherein the retarder is a waveplate whose retardation is equal to &lgr;/4Â±the residual retardation, where &lgr; is a working wavelength of the device.