| 摘要 |
<p>In a solid state laser apparatus, a fundamental laser beam generated in a laser medium is resonated so as to travel through a nonlinear optical crystal element provided within a resonator to thereby generate a secondary harmonic laser light. An optical element is provided within the resonator suppressing coupling caused by a sum-frequency generation between two polarization modes of the fundamental wave laser beam. A control device controls the effective resonator length of the resonator such that the two polarization modes of the fundamental wave laser beam become the same in oscillation intensity. Therefore, mode hopping noise caused by the mode coupling of the fundamental laser beam within the same polarization mode can be avoided and the oscillation can be stabilized. <IMAGE></p> |
