Control system for a two chamber gas discharge laser

A two chamber high repetition rate gas discharge laser system comprising:

• A) a first laser unit comprising:
• 1) a first discharge chamber containing;
• a) a first laser gas and
• b) a first pair of elongated spaced apart electrodes defining a first discharge region,
• 2) a first fan for producing sufficient gas velocities of said first laser gas in said first discharge region to clear from said first 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,
• 3) a first heat exchanger system capable of removing at least 16 kw of heat energy from said first laser gas,
• 4) a line narrowing unit for narrowing spectral bandwidths of light pulses produced in said first discharge chamber;
• B) a second discharge chamber comprising:
• 1) a second laser gas,
• 2) a second pair of elongated spaced apart electrodes defining a second discharge region
• 3) a second fan for producing sufficient gas velocities of said second laser gas in said second discharge region to clear from said second 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,
• 4) a second heat exchanger system capable of removing at least 16 kw of heat energy from said second laser gas;
• C) a pulse power system configured to provide electrical pulses to said first pair of electrodes and to said second pair of electrodes sufficient to produce laser pulses at rates of about 4,000 pulses per second with precisely controlled pulse energies in excess of about 5 mJ;
• D) relay optics for directing laser beams produced in said first laser unit through said second discharge chamber to produce an amplified output beam;
• and
• E) a laser beam control system for measuring pulse energy, wavelength and bandwidth and controlling beam quality parameters of laser beams produced by said laser system.