| 摘要 |
PURPOSE:To obtain a laser diode which enables an economic and highly reliable wavelength multiple optical communication system by providing a plurality of diffraction gratings having different pitches, disposed axially of an active layer, and electrodes disposed near the gratings. CONSTITUTION:A plurality of diffraction gratings G1-G3 having different pitches, disposed axially of an active layer 3, and electrodes Z1-Z3 disposed near the gratings G1-G3 are provided. A laser diode is composed, for example, of a substrate 1 made of N-type InP, an N-type InGaAsP guide layer 2 formed on the substrate 1, an InGaAsP active layer 3 formed on the layer 2, a P-type InP P-type layer 4 formed on the layer 3, an electrode Z10 formed on the lower surface of the substrate 1 and diffraction gratings Z1-Z3. The gratings G1-G3 are disposed axially of the layer 3 on the boundary between the substrate 1 and the layer 2, and the electrodes Z1, Z2, Z3 are opposed to the gratings G1, G2, G3 on the layer 4. |
