Patent ID: 6393040
Filing Date: 2002-05-21
Classification: H01S

Abstract:
A method for selecting a narrow spectral band from the emission spectrum of an excimer laser gas volume and broadening the spectrum of said narrow spectral band, comprising the steps of:generating an emission spectrum by stimulating the emission of radiation from said excimer laser gas volume; optically resonating at least a portion of said emission spectrum along an optical path; selecting a narrow spectral band of wavelengths from within said emission spectrum by suppressing propagation of other portions of said emission spectrum along said optical path; broadening said narrow spectral band by enhancing an intensity of the other portions of said narrow spectral band relative to an intensity of a center portion of said narrow spectral band; and outputting a laser beam, and wherein said laser beam has a reduced temporal coherence length due to said broadening of said narrow spectral band such that modulation due To effects of speckle is reduced.