Liquid crystal polymer viewing angle compensator for liquid crystal display having its largest refractive index in the thickness direction

DETAILED DESCRIPTION In one embodiment of the present invention, a viewing angle compensator for a liquid crystal display is provided which comprises a light transmitting substrate base and a film of a liquid crystalline polymer formed on the substrate, wherein said liquid crystalline polymer in the state of liquid crystal has a structure wherein a refractive index in the thickness direction is larger than a refractive index at least in one direction within the plane of the polymer and assuming a glassy state at a temperature lower than the liquid crystal transition point.
In a second embodiment of the present invention there is provided a viewing angle compensator for a liquid crystal display wherein the liquid crystalline polymer is orientated in a homeotropic fashion in the state of liquid crystal.
In a third embodiment of the present invention there is provided a viewing angle compensator for a liquid crystal display wherein the liquid crystalline polymer is a polyester containing an ortho-substituted aromatic unit.
In a fourth embodiment of the present invention there is provided a viewing compensator for a liquid crystal display using a film obtained by heat-treating a liquid crystalline polymer on a light transmitting substrate at a temperature higher than the glass transition point of the liquid crystalline polymer and then cooling the polymer to a temperature lower than the glass transition point to solidify the structure wherein said polymer has a refractive index in a thickness direction that is larger than a refractive index at least in one direction within the plane of the polymer.
The present invention also provides a process for compensating the viewing angle of a liquid crystal display using the aforementioned liquid crystalline polymer film.