NONTRADITIONAL PRINCIPLES OF POWERFUL LAS ERS DESIGN

A review of papers dealing with pulsed Raman lasers (''beam combining' ' lasers) based on liquid nitrogen, methane and hydrogen as an active media is done. In case of hydrogen both cases, using vibrational and r otational transitions, are considered. The considered pump energies li e in the range of 1 to 250 J. Only those laser schemes and performance are reviewed that allow to scale the obtained results up to higher en ergies. It is shown that Raman lasers can provide considerable gain in brightness and serve as powerful sources of radiation in new waveleng th regions. In those cases when the characteristics of the pumping neo dimium lasers are close to ultimate and there is no need to rise their brightness, the use of Raman laser (''pulse combining'' laser) as an end cascade allow to increase the efficiency of the whole laser system in several times. This opens a new perspectives for creation of laser systems with output energies of the order of 1 kJ and higher.