fiber-optic thermometer

fiber-optic thermometer

[′fī·bər ¦äp·tik thər′mäm·əd·ər] (engineering) A thermometer in which light from a mercury lamp is guided along an optical fiber to excite a tiny fluorescent crystal, whose light is in turn guided back along the fiber to an evaluation unit where the crystal temperature is determined from the ratios of the strengths of spectral lines in the fluorescent light or from the decay time of the fluorescence.