An optical liquid crystal element, a liquid crystal display element and liquid crystal projection display apparatus - of which this element used

摘要

A liquid crystal optical element comprises a pair of substrates with electrodes and a liquid crystal and polymer composite material, which is interposed between the pair of substrates, in which liquid crystal is dispersed and held in a polymer matrix so that the refractive index of the polymer matrix substantially coincides with the refractive index of the liquid crystal used in either state of applying a voltage or without applying voltage, and the refractive indices don't coincide with each other in the other state, wherein the elastic modulus of the polymer material which forms the polymer matrix is 3 × 10⁷ N/m² or less at 20°C and 1 × 10³ N/m² or more at 40°C.