Output coupler design of unstable cavities for excimer lasers

摘要

We tested the performance of a XeCl laser with unstable resonators using as an output coupler a phase unifying (PU) mirror, a super-Gaussian mirror, and a hard-edge mirror. The quantitative impact of the output coupler design on the energy extraction efficiency, near-field profile, far-field energy distribution, and spatial coherence time evolution has been investigated. Laser beams of larger brightness have been obtained with the PU unstable cavity. A faster growth of the laser beam spatial coherence has been observed with the PU cavity by time-resolved, far-field measurements. (C) 1997 Optical Society of America.