MULTIPLE-PULSE AMPLIFICATION IN A KRF LASER.

The KrF laser has a very short storage time, which means that to realize the potential high efficiency, energy must be extracted from the laser continuously. Thus, previous schemes for large KrF laser systems have regarded the laser as a CW device. Recently, it was shown that very short (picosecond) pulses can be amplified to high powers in the KrF laser medium. Preliminary results are presented of experiments carried out to extend these results to high energy, with high system efficiency. This has been done by amplifying a sequence of pulses in a single module. The pulses may be separated in angle (angularly multiplexed) so that they may be recombined simultaneously on target.