PROJECTION DISPLAYING APPARATUS

摘要

PURPOSE: To perform the temperature compensation of a projection display device provided with a liquid crystal display device having the layer of a liquid crystal material between two supporting plates provided with electrodes for stipulating picture elements capable of applying a voltage through the electrodes over the picture elements. CONSTITUTION: Practically parallel light beams 3 are made incident on the liquid crystal display device 4 and the liquid crystal material 13 is present between transparent substrates 7. A simple temperature compensation is performed buy optimizing a d.Δn value (d) is the thickness of a liquid crystal layer, Δn is the difference in refractive indexes between normal waves and abnormal waves} at a maximum operating temperature. Related transmission/ voltage characteristics at different temperatures are practically parallelly extended, and thus, temperature change is compensated by single voltage compensation.