IANUS, THE 3-ELECTRODE EXCIMER-LASER

We present the results of the mechanical, electrical, and optical char acterisation work done on Ianus, a 1 : 1 laser-head prototype of the X eCl (lambda = 308 nm) laser (1-kW output power) developed in the frame of the Eureka EU 213 program. The three-electrode configuration of Ia nus consists of two laser discharges electrically in series, with the same current flowing through the two gaps, but geometrically in parall el. We have experimentally tested and optimised the behaviour of this unconventional laser head with regard to single-shot laser output ener gy, overall efficiency and spatial discharge uniformity, as well as to repetition-rate performance versus a newly defined volumetric flush f actor. The peculiar three-electrode concept makes Ianus suitable for s piker-sustainer excitation and compact oscillator-amplifier configurat ions.