| 摘要 |
<p>The invention relates to a method and a laser device which operates under passive optical switch regime with high energy pulse emission and ultra-short semi-amplitude duration, in the range of nanoseconds. According to the invention, the method is characterized in that, in order to obtain, under passive optical switch regime of the quality factor of the laser resonant cavity, a high-energy laser pulse emission with Gauss or super-Gauss distribution of laser intensity, corresponding to the laser oscillation in TEMmode of high volume, at wavelengths in the spectral range of 1...5μm and semi-amplitude duration approximately equal with the time of passing both ways through said laser resonant cavity, there is employed a passive optical switch, device having a high contrast factor, i.e. having, at the laser wave length, an optical transmittance which varies from a very low initial value to a very high final value corresponding to the laser emission, limited by Fresnel reflections on its optically-active surfaces, as well as laser mirrors having radially variable reflectance according to a Gauss or super-Gauss distribution law. The device claimed by the invention consists of a solid state laser the resonant cavity of which comprises a laser mirror (1) having a reflectance of about 100% at the laser wavelength, a polarizer (2) consisting of a quartz lamella mounted under a Brewster angle as compared to the optical axis of the laser resonant cavity, a passive optical switch (3) of the quality factor of the laser resonant cavity, a solid state laser active medium (4) and a laser mirror (5) having a reflectance at the laser wavelength which is radially variable according to a Gauss or super-Gauss distribution law.</p> |
