1-ns high-power high-repetitive excimer laser oscillator

A 1-ns high-power high-repetitive excimer laser oscillator has been developed for which the peak power obtained was more than 1 MW with 1-ns pulse width for both XeCl and KrF gas mixtures. The characteristic output power per unit active volume is calculated to be more than 2 GW/L, which is nearly one order larger than that extracted from usual discharge devices. It is inferred that the gain depletion in the active medium under such an extremely large output power condition has led to successful pulse shortening. The device can be operated at a repetition frequency of at least 500 Hz without a gas circulation system. The beam divergence was reduced to near the diffraction limit, although the oscillated-pulse width is only 1 ns.<>