Effects limiting the average power of compact pulse-periodic KrF lasers

Comparative investigations were made of the characteristics of two compact KrF lasers with different geometries and different gas flow velocities. The same electric-discharge system, optimised to reach a high KrF laser efficiency (~ 3.5%), was used in both lasers. It was established that at a high pulse repetition frequency the specific nature of acoustic perturbations, which appeared in the gasdynamic channel, influenced the homogeneity of the discharge and of the laser radiation.