Patent ID: 6795474
Filing Date: 2004-09-21
Classification: G03F,H01S

Abstract:
An extreme repetition rate gas discharge modular laser capable of operating at pulse repetition rates in excess of 2,000 pulses per second, said laser comprising:A) a laser chamber module containing: (1) a laser gas, (2) two elongated electrodes, defining a discharge region (3) a tangential type fan for producing sufficient gas velocities of said laser gas in said discharge region to clear from said discharge region, following each pulse, substantially all discharge produced ions prior to a next pulse when operating at a repetition rate in the range of 4,000 pulses per second or greater, and (4) a heat exchanger system comprising at least one finned heat exchangers, said system being capable of removing at least 16 kw of heat energy from said laser gas, B) a pulse power system configured to provide electrical pulses to said electrodes sufficient to produce laser pulses from said discharge region at rates of about 4,000 pulses per second with precisely controlled pulse energies in the range of about 5 mJ, C) a first optics module comprising line narrowing optical components, D) a second optics module comprising an output coupler, said output coupler and said line narrowing module defining a resonant cavity and a laser beam path through discharge region and said laser chamber module and being mounted in said laser separated from said chamber module and E) a beam path purge system for purging portions of said laser beam path, said beam path purge system comprising: 1) a first easy sealing bellows seal unit for providing with said purge system a vacuum quality substantially oxygen free beam path between said chamber module and said first optic module and, 2) a second easy sealing bellows seal unit for providing with said purge system a vacuum quality substantially oxygen free beam path between said chamber module and said second optic module; wherein said first and second easy sealing bellows seals units each can be quickly and easily removed for fast replacement of said chamber module.