Variable reflectivity unstable resonators for a long pulse XeCl excimer laser

摘要

The divergence of a long pulse. low gain XeC1 excimer laser has been improved using confocal positive branch unstable resonators with variable reflectivity mirrors as outcouplers. With variable reflectivity unstable resonators, nearly diffraction limited beams are obtained. Variable reflectivity resonators head to high brightness beams (9.1 × 10~(14) W/(cm~(2) sr)). Different reflection profiles were studied with respect to their influence on the beam quality and the energy extraction.