| 摘要 |
PURPOSE:To improve the conversion efficiency of a wavelength in a nonlinear optical crystal and obtain stable conversion light with a high output. CONSTITUTION:A temperature gradient is provided in a nonlinear optical crystal 3 by each peltier element 10 and 11. For example, the temperature of one side of the nonlinear optical crystal 3 is increased and the temperature of the other side is decreased. Therefore, the deviation of a phase matching angle and the deviation of a phase matching angle due to a beam angle divergence of laser light in the nonlinear optical crystal 3 is canceled, and a large beam section can be obtained by a phase matching on the substantially entire surface of the beam, and a conversion efficiency of a wavelength can be improved. |
