Kilowatt single transverse discharge excited slab waveguide array CO2 laser

Abstract

In the past decade, RF transverse discharge excited diffusively cooled CO2 lasers have experienced the advances from single-channel and folded-channel structures to waveguide array devices in aiming to obtain compact size and high quality beam. In recent years, an area scaling technique with the advantage of simplicity has been reported, which makes use of the slab waveguide large area RF discharge uniform excitation and an optical unstable resonator, and combines the diffusive cooling to make the compact kilowatt CO2 laser into reality. In this paper, we shall present a new technique, single RF discharge excited diffusively cooled 1 × 2 slab waveguide linear array CO2 laser, with which we have obtained over 1 kilowatt power output. In this type of laser structure, the electrode length is only 500 mm, and each array element has a cross section of 99 × 2 mm2. In experiments, the whole waveguide array is excited by a single RF input, and the RF frequency is 93 MHz. The gas mixture pressure is 70 torr with composition of CO2:N2:He:Xe = 1:1:3:5%. The output beam dimension of each array element is 2×16 mm2. In the far field, the two beam spots overlap and are combined into a single peak distribution. Experiments have shown that it is possible to use this technique to produce multikilowatt high beam quality power output from a compact-sized device.