Study On The Noise Characteristics Of All-solid-state Frequency-double Laser

LD pumped all solid state lasers have a variety of applications due to their advantages of compact, small size, high efficiency, good beam equality and so on. Through intracavity nonlinear optical frequency mixing, lasers with the wavelengths that differ from the oscillating wavelengths in cavity can be obtained.The noise proprieties of CW intracavity doubling-frequency blue laser were studied in theory and experiments. The theory of the rate equations of intracavity doubling-frequency multi-longitudinal mode was applied to the quasi-three level blue lasers. The noise cases of single-longitudinal mode, two modes and more than two modes were analyzed. The stability output second harmonic generation experiment results of single-longitudinal mode and multi-longitudinal mode with long cavity were explained reasonably with these rate equations.The high polarization of fundamental wave in the isotropic laser media Nd:YAG with type-I critical phase-matching LBO was studied with the rate equations including polarization of fundamental light. Using the polarization function of LBO, a quartz full-wave plate was introduced into the cavity, a kind of birefringent filter by considering the combination of the polarization function of the type-I critical phase-matching doubling frequency crystal LBO and the quartz whole-wave plate was constructed. The blue laser noise was depressed by selecting single-longitudinal mode. The stable operation of LD pumped Nd:YAG/LBO mas obtained.