Circularly polarized light separation plate, production thereof and liquid crystal display

摘要

Disclosed are a method for producing a circularly polarized separated plate which comprises coating an oriented cholesteric liquid crystal polymer layer with a different kind of cholesteric liquid crystal polymer and heat orienting the resulting coated layer, or heat pressing oriented cholesteric liquid crystal polymer layers on each other, or adhering oriented cholesteric liquid crystal polymer layers to each other through a volatile liquid or a volatile liquid in which a cholesteric liquid crystal polymer is dissolved, thereby forming a close contact laminate of two or more cholesteric liquid crystal polymer layers in which an upper layer is different from a lower layer in helical pitch; a circularly polarized separated plate comprising a close contact laminate of two or more cholesteric liquid crystal polymer layers in which an upper layer is different from a lower layer in helical pitch, the laminate having a mixed layer of cholesteric liquid crystal polymers forming the upper and lower layers, which is different from the upper and lower layers in helical pitch, in a close contact interface thereof to provide multistage changes in helical pitch in the direction of thickness; an optical element in which the circularly polarized separated plate is provided with at least one of a 1/4 wavelength plate and a polarizer; a polarization light source device comprising the circularly polarized separated plate or optical element on a light outgoing side of a light pipe; and a liquid crystal display comprising the circularly polarized separated plate, optical element or polarization light source device on a visual back face side of a liquid crystal cell. <IMAGE>