Deliberation of fluorescent material by used in low temperature measurement

A possibility of low temperature measurement using fluorescence material was examined. Temperature dependence of fluorescence lifetime applied to low temperature measurement. Inorganic fluorescence material is known as a suitable sensor material for temperature measurement. Ruby was used as a sensor material because of bright fluorescence and long fluorescence lifetime. Fluorescence thermometer using the ruby which is modified for temperature measurement has been fabricated. From this research, ruby crystal is found to be useful as the sensor head for fluorescence thermometer. In addition, the ruby crystal is potentially useful material for the sensor head crystals to measure low temperature below 273 K.