| 摘要 |
PROBLEM TO BE SOLVED: To provide a small and inexpensive optical transmitting/receiving module by disposing a laser emitting a light of λ1 and an element receiving a light of λ2 on a same optical axis such that the laser is closer to a fiber than the light receiving element. SOLUTION: A semiconductor laser 70 disposed proximately to the end face of an optical fiber 62 comprises an InP substrate, an active layer (light emitting part) 72, and an epitaxial layer, e.g. an InP clad layer 73 (including a cap layer) and it is stimulated to emit light of λ when a current is injected from a p- electrode 75 toward an n-electrode 74. When a film reflecting the light of λ1 perfectly is provided on the back face of the laser 70, the light of λ1 is not emitted from the rear edge of laser and only the light of λ2 arrives at a light receiving element 85 comprising an InP substrate 86, an InGaAs light receiving layer 87, and annular p-electrode 88 and n-electrode 89. When a 1.3μm LD(λ1 ) and a 1.55μm PD(λ2 ) are arranged sequentially, a module transmitting a signal with 1.3μm pm and receiving a signal with 1.55μm can be realized without requiring any wavelength demultiplexer. |
