Optical Measurement of Electric Field Vector Distribution in a Liquid Insulator UsingSimultaneous Three-direction Optical Measurement System

Abstract

We have already reported on reconstructions of symmetrical and nonsymmmetrical electric field vectordistribution using Kerr electrooptic effect and our unique reconstruction method modified computed tomography technique. This reconstruction technique gives electric field map, i. e., the strength and the directionof electric field vector, on any plane. For the reconstruction of one field vector distribution, it was necessaryto measure light intensity twice with changing the optical axis of optical wedges. Moreover, the intensitymeasurement must be carried out at many points around the electrode system. Therefore it took considerabletime to measure an electric field distribution. So, we developed a simultaneous three-direction optical measurement system with three optical systems combined the two-beam method. Using the new measurement system, we measured the electric field distribution on planes in a sphere-to-sphere electrode system. It tookabout 0.1 seconds to measure the light intensity data for the reconstruction.