| 摘要 |
PURPOSE:To cancel a dark current component, to assemble a light-receiving circuit having excellent temperature characteristics simply and to reduce the cost of a system by forming a light-receiving surface onto one part on the same chip and shaping a light-shielding light-receiving surface having the same size area onto the other section. CONSTITUTION:A light-receiving diode consists of an I layer 1, a P layer 2, an N layer 3, a dark current leading-out electrode 5, a signal leading-out electrode 6 and an SiO2 film 8, and a light-receiving surface in the light-shielding light-receiving diode section shields light by a metallic film composed of aluminum, etc. through an insulating layer 4. Since both sections of the light-receiving diode section and the light- shielding light-receiving diode section are adjoined and have the same manufacturing conditions and also have static conditions after assembly, dark currents are made the same, thus cancelling a dark current component when dark currents are amplified by a differential amplifying circuit 9, then outputting only an optical signal component. Accordingly, light can be received even at a position where an optical input is sufficiently small, and a light-receiving circuit having excellent temperature characteristics is assembled simply especially when receiving an optical signal containing a DC component, thus reducing the cost of the whole system.
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