Patent ID: 6341186
Filing Date: 2002-01-22
Classification: G02B

Abstract:
An optical arrangement comprising:an optical filter responsive to an input signal for generating at an output thereof one of a group consisting of a periodic and aperiodic output response waveform having a rounded passband shape; and an optical flattening filter coupled in cascade with the optical filter between an input and an output of the optical arrangement for generating a response waveform having a spectral profile which is complementary to the periodic or aperiodic output response waveform of the optical filter and interacts with the response waveform of the optical filter such that each peak in a resultant response waveform at the output of the optical arrangement is substantially flattened to provide a passband which is wider than the response waveform provided by the optical filter, wherein the optical filter comprises one of an optical multiplexer and an optical demultiplexer, wherein the optical flattening filter is a Fabry-Perot filter comprising first and second GRIN lenses terminating first and second optical fibers, respectively, wherein the ends of the first and second GRIN lenses opposite the terminated optical fibers are separated by a cavity of a predetermined length such that the Fabry-Perot filter generates a response waveform having a spectral profile which is complementary to the response waveform of the optical filter.