High-quality beam transversal gas transport cw CO2 laser

Abstract

A new optical resonator configuration for transverse flow CO2 laser was developed. A high value of the matching coefficient (the cross section of the laser beam/the cross section of the electrical discharge)-(eta) m, is obtained for laser beams with TEM00/01 intensity distribution (that corresponds to the low values of the Fresnel number-NF of the optical resonator). Simultaneously, both types of the gain and refractive index asymmetries of the active medium (parallel and perpendicular on the flow direction) are compensated. A 90 degree(s) deflection device is the main constructive element (this is built by two mirrors at 45 degree(s) relative angle and offers the pentaprism properties). This deflection device reverses the wavefront in one of the two discharge channel and in addition improved the resonator stability. The main results are (eta) m is congruent to 0.83 for NF is congruent to 1.9 and the beam pattern is independent of the power level in the range of 300 W to 1800 W.