Foley & Lardner
Optical fiber remote sensing system with electromagnetic wave measurement
 Disclosed is an optical fiber remote sensing system, which has: first and second light sources which are connected to ends of branched optical fibers and emit lights with two wavelengths different from each other; one or more optical detectors which conduct a photoelectric conversion of the lights propagated through the optical fibers from the first and second light sources and generate an electromagnetic wave with a wavelength corresponding to a difference between the two different wavelengths; and a measuring means which receives the electromagnetic wave propagated through a measured substance and measures a state of the measured substance based on an optical absorption characteristic of the measured substance. 
NEC Corporation
G
G01N
inventional
Hirohito
Yamada