Acoustic measurement method in investigation of optical phenomena in a modulated CO 2 laser plasma

Abstract

The paper describes the results of investigations of optical phenomena on an RF excited slab-waveguide CO 2 laser. The experiments are performed in two optical arrangements: two-mirror resonator and three-mirror one. The main purpose of the experiments is to check possibilities to observe the optical phenomena using a microphone. The laser plasma is modulated with a self-mixing signal in the three-mirror resonator. The response of the microphone is observed and analyzed. Detection of the laser signature phenomenon with the microphone is experimentally considered. The experiments are done at cw regime of the laser. The investigations are performed at pulse operation of the laser, as well. The response of the microphone is analyzed. It is checked how the laser pulse is reconstructed at a profile of the microphone signal. The output laser pulse with a mapped laser signature in the laser pulse profile is compared to the microphone signal shape. The presence of the laser signature at the acoustic signal is investigated.