Optical apparatus, and wavelength conversion laser light source, image display apparatus, and laser light source device adopting such optical apparatus

摘要

A wavelength conversion laser light source includes: a non-linear optical crystal of an oxygen octahedral structure, having added thereto a metal ion in other components than a main component; a light source for projecting light into the non-linear optical crystal in an operation mode; and a refractive index recovery mechanism for carrying out a recovery operation for recovering a refractive index of said non-linear optical crystal as shifted overtime due to light projected into the non-linear optical crystal in the operation mode with an applied external energy into the non-linear optical crystal in a non-operation mode in which light is not injected to the non-linear optical crystal.