Patent ID: 7184620

Claim:
A three-port single-channel optical add/drop multiplexer (OADM), comprising: a ferrule having an input side and an output side, and an opening formed therethrough; first, second and third optical fibers inserted in the opening and extending outwardly from the input side of the ferrule; a collimating lens positioned on the output side of the ferrule; a filter having a first side and a second side, the first side optically coupled to the collimating lens and being positioned at a non-zero angle relative to a transmission axis of the collimating lens, the filter being operable, over substantially the filter's entire extent, to pass one or more particular wavelengths within a passband of the filter to a reflector and the filter being operable to reflect one or more particular wavelengths within a reflection band of the filter back through the collimating lens to the third optical fiber; and the reflector, coupled to the second side of the filter, and at an angle to the filter such that an optical signal transmitted through the filter from the first optical fiber is reflected back through the filter and collimating lens to the second optical fiber.