| 摘要 |
PROBLEM TO BE SOLVED: To cancel the deterioration of optical sensitivity by connecting probe impedance with a pair of optoelectronic pnpn devices, and operating the differential connection of the both devices for allowing it to act as a transceiver. SOLUTION: Probe impedance (searching impedance) Za and Zb are serially connected with a pair of pnpn devices Ta and Tb. A small optical pulse is added to the device Ta before a point of time 0 ns, a voltage Vs is jumped to 5 V at a point of time 0 ns, and a normal feedback operation is started at a point of time 0.1 ns, and the device Ta is turned ON and light emission is operated. It is judged that the pnpn devices are turned into closed states by those detection voltages, and optic/electric conversion can be detected by reading this detection voltage difference. When any light input is absent, the small injection currents of either a detection node Pa or Pb provide the similar excess operation at a certain point of time between 0 ns and 0.3 ns. |
