Patent ID: 6606197
Filing Date: 2003-08-12
Classification: G02B

Abstract:
A method of filtering an input beam of light having a plurality of desired wavelength components and a plurality of unwanted wavelength components so as to provide a filtered output beam of light comprising the desired wavelength components, the method comprising:dividing the input beam into a plurality of polarized beamlets that travel along spatially separated beam paths, said beamlets comprising (a) a plurality of desired beamlets corresponding to the desired wavelength components and (b) a plurality of unwanted beamlets corresponding to the unwanted wavelength components; separating the desired beamlets from the unwanted beamlets; and combining the desired beamlets so as to provide the filtered output beam, wherein dividing the input beam comprises converting the input beam into at least one linearly polarized beam; and diffracting the input beam, wherein converting the input beam into the at least one linearly polarized beam comprises converting the input beam into a first and second s-polarized beam, and wherein diffracting the input beam comprises directing the at least one linearly polarized beam through a light dispersing element having a diffraction grating so that the at least one linearly polarized beam is diffracted by the diffraction grating.