A LOW-TEMPERATURE COEFFICIENT OPTOMODULATOR FOR ANALOG SIGNAL TRANSMISSION

A Mach-Zehnder type optomodulator has been investigated for the last q uarter of a century, but its application for analog signal transmissio n in a physics experiment is a quite new idea. Recent studies have pro ven that Mach-Zehnder type optomodulators have a good potential in suc h applications. It will enable more than an order of magnitude reducti on of cable volume and will be free from noise pickup and cross talk. Almost no attenuation through a long signal path in light fibers is al so an asset when a detector size is very large. Power consumption is a lso minimal. If it does not have too large a temperature coefficient, it could be an excellent device for future experiments. We have studie d its temperature coefficent and developed a unit that has low enough temperature coefficient so that it could be used for some physics expe riments. A light wavelength of 1.55 micron was chosen for the unit.