Patent ID: 7209612
Filing Date: 2007-04-24
Classification: G02B

Abstract:
1. A two stage optical filter planar lightwave circuit device for receiving first and second input channels from a system waveguide and for transmitting an output channel onto the system waveguide comprising: a laser transmitter for transmitting the output channel; a non-diffractive filter, having a first passband for multiplexing the output channel onto the system waveguide, and for separating the first and second input channels from the output channel; a diffraction grating filter for demultiplexing the first and second input channels, each of the first ands second input channels having a second passband narrower than the first passband, including: first and second output waveguides optically coupled to the first and second ports, respectively for transmitting the first and second input channels, respectively; and first and second photo-detectors optically coupled to the first and second output ports, respectively, for converting the input channels into electrical signals.