Wavelength conversion laser light source having dual optical receiver and a temperature control unit, and projection display device, liquid crystal display device and laser light source provided with same

Abstract

A wavelength conversion laser light source includes: a fundamental light source for outputting fundamental light; a wavelength conversion element with a nonlinear optical effect for converting the fundamental light into harmonic light of a different wavelength; a first optical receiver for receiving light of a specific polarization direction contained in the fundamental light output from the fundamental light source and converting an amount of light thereof into an electrical signal; a second optical receiver for receiving the harmonic light output from the wavelength conversion element and converting an amount of light thereof into an electrical signal; a temperature holding unit for holding a temperature of the wavelength conversion element constant; a fundamental light control unit for performing first control of controlling an amount of light of the fundamental light output from the fundamental light source based on the electrical signal from the second optical receiver, and second control of controlling an amount of light of the fundamental light based on the electrical signal from the first optical receiver; and a temperature control unit for performing third control of controlling a holding temperature of the temperature holding unit based on the electrical signal from the second optical receiver.