| 摘要 |
PURPOSE:To obtain a light memory device in which a storage is held even if a light is not emitted at normal time by connecting in parallel light bistable elements which become ON/OFF states at the outputs when an input light is 0, and a phototransistor for turning OFF the elements by the light. CONSTITUTION:A P-type clad 11, an active layer 10 and an N-type clad 9 form a light emitting element 12, the first collector 9, the first base 8 and the first emitter 7 form the first phototransistor 13, and the second collector 7, the second base 6 and the second emitter 5 form the second phototransistor 14. The element 12 and the phototransistor 13 are connected in series, and they are connected in parallel with the phototransistor 14. A write signal light is input to the phototransistor 13, and an erasing signal light is input to the phototransistor 14. The phototransistor 13 also receives an output light from the element 12 in addition to the write signal light, but the phototransistor 14 does not receive the output light. |
