OPTICAL COMMUNICATION DEVICE

摘要

An optical communication device (an LD module or an LD/PD module) having a flat substrate, a light waveguide layer formed upon the substrate with a core for guiding signal LD light, an LD bonded upon a part of the substrate without the whole or a part of the light waveguide layer for producing signal front light and monitoring rear light, a path conversion groove being perforated along the core on the substrate behind the LD and having slanting walls for reflecting rear light emitted backward from the LD, a bottom- or t op- incidence type PD bonded upon the light waveguide layer over the path conversion groove for monitoring the LD power by detecting the LD rear light reflected by the path conversion groove. Since the PD level is higher than the LD by the thickness of the light waveguide layer, the monitoring PD can sense more than 50% of the LD rear light.