Patent ID: 6504861
Filing Date: 2003-01-07
Classification: G03F,H01S

Abstract:
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 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 including a compartment valve-coupled between gas supply lines and the discharge chamber; and a processor for controlling gaseous flow between said gas supply unit and said discharge chamber, wherein said gas supply unit and said processor are configured to permit between 0.0001 mbar and 0.2 mbar of said constituent gas to inject into said discharge chamber at selected intervals, and wherein an amount of constituent gas injected is varied based on a calculated amount of constituent gas injected in a previous injection, and wherein said calculated amount of constituent gas injected in said previous injection is determined based on an amount of said constituent gas known to be in the compartment prior to said previous injection.