Patent ID: 7643529

Claim:
An apparatus comprising: a narrow band pulsed lithography laser light source comprising: a seed pulse providing laser system comprising: a single pulsed solid state seed laser with a nominal center wavelength outside of the UV range and operating at 2X kHz; an amplification system comprising: a first amplifier gain system comprising a first and a second pulsed gas discharge amplifier gain medium, each with a nominal center wavelength in the UV range, and each operating at ½ X kHz on output pulses from the first seed laser system; and a second amplifier gain system comprising a first and a second pulsed amplifier gain medium, each with a nominal center wavelength in the UV range, and each operating at ½ X kHz on alternating output pulses from the second seed laser system; a seed pulse divider providing pulses from the solid state seed laser to a first amplifier gain system pulse divider and to a second amplifier gain system pulse divider, the first amplifier gain system pulse divider providing pulses to the first and second pulsed amplifier gain mediums of the first amplifier gain system and the second amplifier gain system pulse divider providing pulses to the first and second amplifier gain mediums of the second amplifier gain system; and a pulse combiner combining the output pulses from the first and second amplifier gain systems to produce a light source output laser light pulse beam at a pulse repetition rate of 2X kHz.