Optical device, laser beam source, laser apparatus and method of producing optical device

Abstract

After forming domain inverted layers 3 in an LiTaO 3 substrate 1, an optical waveguide is formed. By performing low-temperature annealing for the optical wavelength conversion element thus formed, a stable proton exchange layer 8 is formed, where an increase in refractive index generated during high-temperature annealing is lowered, thereby providing a stable optical wavelength conversion element. Thus, the phase-matched wavelength becomes constant, and variation in harmonic wave output is eliminated. Consequently, with respect to an optical wavelength conversion element utilizing a non-linear optical effect, a highly reliable element is provided.

1 . A laser device, comprising:
 at least one laser light source including a semiconductor laser;   a first optical system for irradiating a spatial modulation element with laser light emitted from the laser light source; and   a second optical system for irradiating a screen with the light emitted from the spatial modulation element,   wherein the laser light source further includes:   a fiber for conveying laser light from the semiconductor laser;   a solid state laser crystal for receiving laser light from the fiber and generating a fundamental wave; and   a bulk type optical wavelength conversion element in which periodic domain inverted structures are formed, the optical wavelength conversion element receiving the fundamental wave and generating a harmonic wave,   wherein the fiber is configured to prevent a variation in temperature of the optical wavelength conversion element caused by a heat generated from the semiconductor laser.   
     
     
         2 . A laser device according to  claim 1 , wherein the spatial modulation element is a liquid crystal cell. 
     
     
         3 . A laser device according to  claim 1 , wherein the semiconductor laser is wavelength-locked. 
     
     
         4 . A laser device according to  claim 3 , wherein wavelength-locking is performed using a grating or a filter.