Investigation of slab cavity cleanliness of high power laser amplifiers

Experimental research of the slab cavity cleanliness of high power laser amplifiers is presented in this paper. The results indicate that materials within the slab cavity are readily pyrolyzed due to flashlamp high irradiance, and thus produce large quantity of airborne particles at the scale of micrometers. Experiments are carried out at two conditions, one of which is measuring the particles without nitrogen flushing, and the other is measuring the particles with several minutes of high flow nitrogen flushing slab cavity immediately after flashlamp pumping. Experimental results show that Class100,000~500,000 aerosols (diameter ³ 0.5m m) are usually produced immediately following the flashlamp firing. Flushing of the slab cavity with a high flow of filtered nitrogen can significantly