A transceiver module comprised of a multiplexing/demultiplexing optical subassembly is provided. The optical subassembly includes either a transmitter module or a receiver module or both. The transmitter module has laser diodes emitting optical signals, which are reflected by reflectors, and coupled together by thin film filter. The receiver module includes thin film filters that decouple a received optical signal into constituent components. These components are reflected by reflectors to photo detectors by which the optical signals are converted into electrical signals. The reflector are capable of dual axis adjustment for adjustment of inclination thereof to effect active alignment. Further, the transmitter module and the receiver module define positioning recesses to position the laser diodes and photo detectors. The recesses are sized in accordance with the wavelengths associated with the laser diodes and photo detectors to effect passive alignment.