Patent ID: 9450370
Filing Date: 2016-09-20
CPC Classification: H01S

Claim Text:
1. A planar waveguide laser device comprising: a laser medium that is shaped like a plate and has a waveguide structure in a direction of a thickness of a surface thereof perpendicular to an optical axis thereof, and that has a characteristic of generating a gain for both light rays which have equal wavelength and are polarized in directions perpendicular and horizontal to a waveguide of said waveguide structure, the laser medium outputting fundamental laser light which includes light rays having a perpendicular polarization and a horizontal polarization; a nonlinear material that is placed on the optical axis of said laser medium close to said laser medium and has a waveguide structure in a direction which is same as that of the waveguide structure of said laser medium, and that performs wavelength conversion on the fundamental laser light to generate harmonic laser light; and a ¼ wavelength plate that is placed close to an opposite side to the laser medium with respect to the nonlinear material along the optical axis, and that rotates by 90-degrees a polarization direction of the fundamental laser light coming from the nonlinear material and returns the rotated fundamental laser light to the nonlinear material, the ¼ wavelength plate including a first surface facing with the nonlinear material and a second surface being an opposite side to the first surface along the optical axis.