| 摘要 |
A laser oscillator comprising a means for oscillating a basic wave by pumping a pumping medium (3) with a pumping light source (7), an output sensor (6) for measuring the average output or the pulse energy of the basic wave, a wavelength conversion element (5) arranged on the optical path of the basic wave and converting the basic wave into harmonic laser light, and a controller (9) for storing a judgment value set lower than a breakdown threshold for the average output or pulse energy of laser light from the wavelength conversion element (5) and controlling the output of the basic wave to below the breakdown threshold when the measurement of the output sensor reaches at least the judgment value. Consequently, the wavelength conversion element (5) can be protected against damage by confining the beam strength in the wavelength conversion element (5) to within the breakdown threshold. |
