Disclosed is an optical
transceiver subassembly module for
multiplexing and demultiplexing a plurality of channels of different wavelengths. The optical subassembly module includes a
transmitter optical subassembly (TOSA) and a
receiver optical subassembly (ROSA). For a TOSA, the optical signals emitted by four
laser diodes of different wavelengths are combined into a multiplexed optical
signal, through respective thin film filters and lenses, which is then coupled onto an
optical fiber after passing through a focusing lens. For a ROSA, the input optical
signal on the
receiver end of the
optical fiber is separated into multiple
optical wavelength signals, through respective thin film filters and lenses, which are then registered by respective photo detectors. This optical subassembly module with compact star-shaped
optics design, active and passive alignments is able to attain high
coupling efficiency between optical signals and the
optical fiber.