| 摘要 |
PURPOSE:To obtain a laser in which an output light is not fluctuated without influence of a retardation of a KTP crystal by controlling the retardation of a nonlinear optical crystal to an integer times of half a wavelength of a basic wave. CONSTITUTION:A solid-state laser such as Nd:YVO4 to be excited by a pumping light of a semiconductor laser 1 constitutes a resonator between an output mirror 2 and an end face of a semiconductor laser side of an Nd:YVO4 crystal 3, and oscillated. Since the crystal is uni-axial in this state, a basic wave laser light to be oscillated is a linearly polarized light 4 parallel to a c-axis of the crystal. When a KTP 5 is, for example, inserted to the resonator as a nonlinear optical crystal for generating harmonic waves, a polarized state of a basic wave is eliminated by the linearly polarized light due to retardation of the KTP. Then, the KTP is operated as a wavelength plate of integer times of half a wavelength by specifying the crystal length of the KTP. |
