Patent ID: 7599410
Filing Date: 2009-10-06
Classification: H01S

Abstract:
1. A semiconductor-diode-pumped solid state laser device comprising: a non-linear optical crystal and a solid etalon, which are accommodated in an optical resonator including a solid state laser medium excited by a laser beam outputted from a semiconductor laser, wherein only a second harmonic wave of a fundamental wave oscillating in the optical resonator is outputted to an external part, a part of the second harmonic wave is detected and a driving current of the semiconductor laser is controlled by a driving circuit based upon the detected second harmonic wave so that the output of the second harmonic wave is constant, wherein the solid state laser medium is composed of Nd: YAG, said second harmonic wave consists of light having a wavelength between 557 and 559 nm, and the free spectral range of the solid etalon is any of the values of the ranges of 1.04 to 1.07 nm, 1.42 to 1.61 nm, 2.07 to 2.14 nm and 2.37 to 3.21 nm.