Phosphor-based fiber optic temperature sensors for harsh environments

A novel approach to the implementation of a fiber optic thermometer with high temperature capability is described. It utilizes a phosphor in the form of a microsphere. With this design, a fiber optic thermal probe having a useful range of 100-1,100 °C has been demonstrated using an LED as the excitation source. From previous work, we believe that it should be possible to extend the maximum operating temperature of such a device to at least 1,400 °C if a laser diode is employed as the excitation source.