JPS5610989A - Laser oscillator - Google Patents

Abstract

PURPOSE:To obtain the high power and small-sized laser oscillator by cooling medium gas directly by using the thermodynamic cooling effect caused upon expansion of gas produced when introducing high pressure gas into a laser discharge tube. CONSTITUTION:A flange 13 operating also as an electrode is fixed at each of both ends of a discharge tube 1 made of an outer tube 1a and an inner tube 1b including a number of fine holes 10. When compressed gas is introduced through a conduit 14 into the tube 1 after cooling the gas via a heat exchanger, high pressure is retained between the outer and the inner tubes to inject gas through the holes 10 into the inner tube 1b. The inner tube is evacuated through an exit 12 to retain at low pressure to diffuse the gas thus injected momentarily in the tube. The CO2 gas thus injected is lowered to several tens degrees below zero due to the cooling effect of gas expansion. The CO2 molecules of low level diffused and heated by the discharge are collided with neutral molecules of low temperature to heat exchange therebetween so as to uniformly cool to the center of the discharge tube. Accordingly, it can obtain easily the effect in the vicinity of high speed convection cooling by the small evacuation unit.