High-temperature thermometer with fiber optic readout

Ultra-high temperature measurement is required in many harsh environment applications such as temperature monitoring in combustors and furnaces. This paper presents a novel thermometer, which is capable to measure temperatures above 1000°C with high resolution and accuracy. This sensor functions as a gas thermometer with a fiber optic readout, which will not suffer from blackbody radiation noise. The sensing part has high hardness, good electrical insulation, good wear resistance and does not react with most chemicals. The size of the sensor can be chosen flexibly to satisfy different application requirements. Since no electrical components are involved, the sensor is spark/explosion free and immune to electromagnetic interference (EMI). The sensor structure is simple, easy to fabricate and low cost. Some temperature measurement results in the laboratory are presented.