The performance of a homemade transversely excited atmospheric CO2 laser, capable to be alternatively run using UV spark pin-array (SPA) and printed circuit board (PCB) surface plasma pre-ionization systems, is comparatively studied. The pin-array configuration is comprised of two rows of 5 mm spark gaps symmetrically located on either side of the discharge volume. The surface plasma pre-ionization system consists of a PCB of which, one side is patterned with isolated millimeter size circular pieces. The performance of both types of pre-ionization in different working conditions was experimentally investigated and the output energies were compared with each other as well as the simulation results based on the six-temperature vibrational-rotational model. It has been found that the SPA system provides better discharge stability and uniformity with higher output energies, while using the PCB surface plasma configuration allowed the laser to operate with higher gas lifetime and lowered the need for helium in its gas mixture.

The output characteristics of a UV pin array pre-ionized transversely excited atmospheric CO2 laser have been experimentally studied in detail. The effects of the applied voltage and capacitance of the main capacitors on the laser performance was investigated. By increasing the voltage at a constant capacitance, not only the laser output energy increases, but also the pulse build-up time, width and tail length decrease. Also, the stability conditions of the discharge were investigated and the cross section of the laser output beam at different input energies was compared.