Patent ID: 6400856
Filing Date: 2002-06-04
Classification: G02B

Abstract:
A polarization independent optical filter for receiving from an optical source a polarized wavelength-division multiplexed (WDM) optical signal having a plurality of wavelengths and defining random first and second polarizations, said filter comprising:an input waveguide having a first width and a second width and for receiving the polarized WDM optical signal; an output waveguide for outputting from said filter a polarized optical signal having a predetermined wavelength that is one of the plurality of wavelengths of the WDM optical signal and having the first and second polarizations; a first resonator, tuned to said predetermined wavelength and one of the first and second polarizations and optically coupled to said input waveguide and separated therefrom by a gap for optically coupling from said input waveguide a part of the optical signal having one of the predetermined wavelengths and one of the first and second polarizations; a second resonator, tuned to said predetermined wavelength and the other one of the first and second polarizations and optically coupled to said input waveguide, and separated therefrom by said gap, for optically coupling from said input waveguide another part of the optical signal having the predetermined wavelength and the other one of the first and second polarizations; said first and said second resonators respectively coupling said part and said another part of the optical signal at said predetermined wavelength to said output waveguide which outputs from said filter an optical signal at said predetermined wavelength and having the first and second polarizations.