| 摘要 |
PURPOSE:To achieve a bistable state within some range of light input in a light emmision functioner by a method wherein a photodetector is installed in an immediate front of an LED, and a detection output is amplified to use for excitation current of the luminous device. CONSTITUTION:By exciting an LED 1 with a power supply 2, an output Pe is emitted. When an output 3 is detected at a detector 4, a detection current Je has a set relation with output Pe. A current Jf wherein a fixed D.C. voltage is added to up to m-th order nonlinear terms is generated at a generator 6 based on Je, and is mixed with an excitation current and then applied to the LED 1. With application of Jf, the photooutput Pe allows demonstration of bistable nature. Within the region that the number of photons n is propeortional to a light power, the characteristic curve of n versus Je-loss gamma draws a fixed hysteresis at m=2nd order. Furthermore, a je-Jp curve shows various characteristics according to selection of a factor of a feedback current, by using this variable characteristic, a special equipment can be constructed, which sharpens a photooutput pulse, performs high-speed switching and logical element movement against a pulse exciation current. |
