Patent ID: 8369366

Claim:
A semiconductor laser excited solid state laser device comprising: a semiconductor laser that oscillates a pumping laser light; a solid state laser medium that outputs a fundamental wave by being pumped by the pumping laser light; a Q switch element; a second harmonic generation crystal that outputs a second harmonic wave from the fundamental wave; and a third harmonic generation crystal that outputs a third harmonic wave from the fundamental wave and the second harmonic wave; and wherein the second harmonic generation crystal is a PPMgSLT that is a quasi phase matching element obtained by forming a polarization inversion structure in a magnesium doped stoichiometric LT; wherein the third harmonic generation crystal is a type I nonlinear optical crystal; and wherein laser light traverses a path between the third harmonic generation crystal and the second harmonic generation crystal without polarization manipulation along said path therebetween.