Patent ID: 7277641

Claim:
A multiple access optical communication device, comprising: an optical signal multiplexer/demultiplexer operable to at least one of multiplex and demultiplex optical signals, including: a primary optical signal polarization discriminator, including: a primary polarizing beam splitter defining two signal transmission paths; a first wavelength discriminator assembly, including: a first polarizing beam splitter located within a first of said two signal transmission paths but not within a second of said two signal transmission paths; a first quarter wave plate, wherein said first quarter wave plate is located within a transmission path of said light reflected by said first polarizing beam splitter; and a first bandpass filter, wherein said first bandpass filter is substantially normal to said transmission path of said light reflected by said first polarizing beam splitter, wherein said first bandpass filter receives light from said first quarter wave plate, wherein light having a wavelength within a passband of said first bandpass filter is passed as a first communication channel, and wherein light having a wavelength outside of said passband of said first bandpass filter is reflected; a second quarter wave plate, wherein light reflected by said first bandpass filter is transmitted by said first polarizing beam splitter and is incident upon and transmitted by said second quarter wave plate; and a second bandpass filter, wherein said second bandpass filter is substantially normal to a transmission path of said light reflected by said first bandpass filter, wherein light having a wavelength within a passband of said second bandpass filter is passed as a second communication channel, and wherein light having a wavelength outside of said passband of said second bandpass filter is reflected.