Control of high power CO2 laser beam by adaptive optical elements

Abstract The spatial and temporal beam characteristics of a cw pumped CO 2 laser with active mirrors in the cavity have been investigated. The five-pass unstable cavity with magnification M = 2 was used, where one of the folding mirrors was replaced by a water cooled flexible mirror based on a bimorph piezoelement. The pulse-periodical regime of the laser generation in different frequency range of controlling signals with a 100% beam power modulation depth was realized. The maximal pulse power value exceeding three times the average power level was obtained at 3.8 kHz pulse repetition frequency. The modulation and stabilization of the output power of a CO 2 100 W laser with a Fabry-Perot interferometer was realized.