Optimization of optically powered sensors

The author has succeeded in achieving power supply for a distance of 1 km using a newly developed optically powered sensor system powered by pulsed light. This system employs the method of matching the impedances of load and of a photodiode by the optical/electrical conversion of pulsed light with a photodiode and boosting the voltage with a transformer. A high optical/electrical energy conversion efficiency of 14.8% was obtained from this system. By driving the semiconductor pressure sensor section with an optical input of 2.33 mW, sensing of a 1 km optical fiber cable length was realized. The accuracy of the prototype optical-power-supply-type pressure sensor was at a high level of ±0.2%. A prototype of a microcomputer-mounted `smart´ detector was fabricated