Laser cavities with diffraction gratings in autocollimation mode
Abstract
Frequency selective losses in laser cavities with circular apertures containing diffraction gratings are investigated experimentally and theoretically. A cavity incorporating a tilted plane mirror used to compute the frequency selective loss function is described. Calculations for a wide range of cavity parameters make it possible to apply the findings to infrared lasers, for which the region of confocality and Fresnel number of parameters employed is characteristic. Carbon dioxide laser experiments confirm the findings. The influence of radial inhomogeneity of the active medium is found to consist primarily of changes in the amount of nonselective losses as compared with a hollow cavity. Selective losses remain practically unchanged. The influence of the beam spreader on the selectivity is found to be insufficient in certain cases for realizing an amplification zone above the threshold, even for comparatively low pressure lasers.
- Publication:
-
USSR Rept Phys Math JPRS UPM
- Pub Date:
- January 1986
- Bibcode:
- 1986RpPhM.......18B
- Keywords:
-
- Carbon Dioxide Lasers;
- Collimators;
- Fresnel Diffraction;
- Gratings (Spectra);
- Laser Cavities;
- Computation;
- Infrared Lasers;
- Inhomogeneity;
- Losses;
- Selectivity;
- Lasers and Masers