ELECTROMAGNETIC FIELD MEASUREMENT DEVICE

摘要

Provided is an electromagnetic field measurement device which can accurately and timely detect a circuit operation in a region where electronic devices are mounted with a high density. The electromagnetic field measurement device includes: a laser light source; a polarization controller which rectilinearly polarizes the laser light; an optical fiber probe having an electro-optical material or a magneto-optical material at a tip end thereof so that a laser light reflected by the tip end is subjected to polarization modulation in accordance with the electric field intensity or the magnetic field intensity at the tip end; and a photo-detector which converts the laser light reflected by the optical fiber probe into an intensity-modulated light. The laser light source has: an optical circulator which emits laser lights of different wavelengths by time division and outputs laser lights rectilinearly polarized by the polarization controller, to a multiplexer/demultiplexer and outputs the laser light inputted from the multiplexer/demultiplexer to the photo-detector; and the multiplexer/demultiplexer which outputs laser lights of respective wavelengths to different optical fiber probes and outputs the laser lights to the optical circulator.