Optical wavelength division multiplexer and/or demultiplexer mounted in a pluggable module

Claim 1

A low profile optical wavelength division multiplexer and demultiplexer device wherein n channels are transmitted on n different wavelengths, and said device is carried in a pluggable module, and adapted for detachable connection to a host device, comprising: a low profile pluggable module having first and second ends, first and second low profile optical subassemblies (OSAs) wherein said first OSA includes a fiber optic cable receptacle and a collimating lens optically coupled to said fiber optic cable receptacle, said first OSA being mounted in said pluggable module so that said fiber optic cable receptacle is positioned at said first end of said housing, means for removably plugging said pluggable module into said host device to achieve an electrical interface between said module and said host device, and wherein said first OSA has three strata including a substrate forming a first stratum, a molded plastic coupling module forming a second stratum, and an optical block forming a third stratum, said molded plastic coupling module carrying a said fiber optic cable receptacle and said collimating lens, said substrate carrying either a plurality of n lasers or n photo-detectors, said molded coupling module connected to said substrate and carrying a plurality of n lenses for either receiving light from said n lasers or focusing light on said n photodetectors, said optical block connected to or integrally formed with said molded coupling module, said optical block having a flat surface carrying a reflective coating, a plurality of n filters whereby said n channels are reflected between said reflective coating on said optical block and said plurality of n filters, and wherein each of n channels passes through one of said filters and through one of said n lens surfaces, and said three strata adapted to be connected together such that the optical elements are passively aligned with said fiber optic cable receptacle and no post-assembly alignment is required.