| 摘要 |
PURPOSE:To enable a high conversion efficiency and an improved laser beam to be obtained by providing an angular phase conformity type non-linear optical crystal as the second harmonic generating element and by providing an adjusting system of the diameter of laser beam and the length of non-linear optical crystal. CONSTITUTION:By allowing a laser beam generated from an oscillator to incide the second harmonic generating element formed from a non-linear optical crystal body, a laser beam wavelength is converted. In this case, an angular phase conformity type crystal is used as a non-linear optical crystal body. A crystal such as KTiOPO4 and beta-BaB2O4 can be used. By using a non-linear optical crystal body of angular phase conformity type to adjust the length of laser beam diameter and that of this crystal body, the second higher harmonic of higher efficiency can be generated. A laser oscillator has for example a laser oscillating element 1, an output mirror 2, and a plain all-reflection mirror 3 and a collimater lens for collecting light 4 and the second higher harmonic generating element 5 using a non-linear optical crystal are provided between this output mirror 2 and the plane total-reflection mirror 3. |
