摘要 |
A fiber optic thermometer is provided that uses a birefringent polarization maintaining sensing fiber as well as a single-mode transmission fiber for transmitting the optical signals between the sensing head and an optoelectronic module. The optoelectronic module contains two light sources operating at different spectral ranges. The unpolarized light from the light sources is sent through the transmission fiber, sent through a polarizer, and coupled into both birefringence axis of the sensing fiber. The waves are reflected at a reflector at a remote end of the sensing fiber, whereupon it returns through the sensing fiber, the polarizer and the transmission fiber. By analyzing the returned signal for both spectral ranges, a robust temperature signal can be derived. This thermometer design obviates the need for using a polarization maintaining fiber and polarization maintaining connectors between the optoelectronic module and the sensor head.
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