PHOTO OSCILLATING CIRCUIT

摘要

PURPOSE:To convert the change in the quantity of light to oscillation frequency by inserting a resistance between the point of connection of a power source and a photo diode and the point of connection of the base and collector of two transistors and also inserting a capacitor in parallel with the photo diode. CONSTITUTION:The base of a PNP transistor Tr1 is connected to the collector of an NPN Tr2 and the collector of Tr1 is connected to the base of Tr2. A series circuit consisting of a power source V and a photo diode D is inserted between the emitter of Tr2 and the emitter of Tr1. A resistance R is inserted between the point of connection of the power source V and diode D and the point of connection of the base of Tr1 and the collector of Tr2 and a capacitor C is inserted in parallel with the diode D. Thereby, the change in the quantity of light may be converted to oscillation frequency by the simple constitution.