The divergence of a long pulse, low gain XeCl 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 lead to high brightness beams (9.1 10 W/(cm sr)). Different reflection profiles were studied with respect to their influence on the beam quality and the energy extraction.
- Electromagnetic wave diffraction
- Laser beams
- Laser pulses
- Optical resonators
- Excimer lasers
- Light reflection
- Confocal positive branch unstable resonators