Resonator with raster collimators for short-wavelength plasma lasers

An analysis is made of a resonator for short-wavelength plasma lasers in which the mirrors are protected from the plasma products and scattered radiation of the heating laser by raster collimators in the form of a set of plates or tubes (microchannel plates). The resonator makes it possible to bring the mirrors closer to a plasma filament and thus increase the efficiency of utilization of the energy stored in media characterized by a short population-inversion lifetime. The range of permissible values of the parameters of these collimators is determined. Computer calculations are used to show that lasers with such resonators should be capable of emitting radiation subject to a relatively slight deterioration in the characteristics. Direct experiments are reported and they demonstrate the effectiveness of mirror protection by tubular collimators.