位相差補償素子及び投射型画像投影装置

Japanese Patent JP6502021

B2

A phase difference compensating element that can effectively compensate polarization disturbance, and a projection-type image projecting device are provided. The phase difference compensating element includes: a birefringent layer formed with a film stack of obliquely-deposited films, each of the obliquely-deposited films having a thickness equal to or smaller than the used wavelength; and an Rd-AR film that is formed with a film stack of two or more kinds of dielectric films having different refractive indexes, and provides an arbitrary phase difference to a phase difference in obliquely-incident transmitted light in the birefringent layer. The phase difference Rd to be provided by the Rd-AR film satisfies 1