Patent ID: 7266137

Claim:
A gas discharge laser system, comprising: a discharge chamber containing a laser gas mixture including a constituent gas which is subject to depletion; a plurality of electrodes connected to a power supply circuit for providing a driving voltage to said electrodes as a pulsed discharge to energize said laser gas mixture; a resonator surrounding said discharge chamber for generating a pulsed laser beam; a gas supply unit connected to said discharge chamber; and a processor for controlling gaseous flow between said gas supply unit and said discharge chamber, the processor configured to control the gas supply unit to inject a selected amount of constituent gas into said discharge chamber at selected intervals, at least one of the selected intervals and the selected amount of each constituent gas injection depending upon an amount of input electrical energy applied to the pulsed discharge in the laser gas mixture; wherein the selected amount of the constituent gas injection for at least one of the selected intervals is between 0.0001 mbar and 0.2 mbar of said constituent gas or between 0.003% and 7% of said constituent gas presently within said discharge chamber.