OPTICAL ELECTRIC VOLTAGE/ELECTRIC FIELD SENSOR CORRESPONDING TO DIRECT CURRENT AND ISOLATED AMPLIFIER

摘要

PROBLEM TO BE SOLVED: To detect a direct current component by using a pulse laser light and separating the variation of laser light transmittance and electric field dependent variation of an optoelectrical field sensor in an optical system between converters from the optoelectrical field sensor.;SOLUTION: The optoelectrical field sensor 4 and a delay optical path 5 bypassing it are provided. A laser pulse is guided with an optical fiber 2 and the like to the optoelectrical field sensor 4 and a part of light is let pass the delay optical path 5 with a beam splitter 3 at immediately before the optoelectrical field sensor. Electric field amplitude modulated light (waveform 2) from the optoelectrical field sensor and light having passed the delay path (waveform 3) are added with a beam splitter 6 (waveform 4) to introduce in an optical fiber 7 and the like. During the passing time of delay optical path 5 of the received light pulse, modulated light (waveform 2) only from the optoelectrical field sensor 4 comes in. The emission light of the optical fiber 7 and the like is a sum of Lm and the delay path passing light (waveform 3) after the delay time and Lr(= Lp - Lm) is not affected by electric field. Correcting the variation other than the optoelectrical sensor from the light intensity, the electric field intensity of the optoelectrical field sensor 4 is known without depending on the optical system.;COPYRIGHT: (C)2007,JPO&INPIT