Fluorescence Thermo-Sensor Sheet Using Cr Doped YAlO3 Crystals

Fluorescence sensor sheet has been fabricated successfully by Cr doped YAlO₃ powder and silicone resin, and characterized for applications as the thermo-sensor material. Fluorescence thermometer system using fluorescence sensor sheet enables non-contact temperature measurement in extraordinary conditions. In this system, temperature measurement technique based on the temperature dependence of Photoluminescence (PL) intensity ratio is more convenient and practical system than that using temperature dependence of PL lifetime. Among many phosphors, Cr doped YAlO₃ is found to be useful as the sensor materials for fluorescence thermometer sheet because of its long PL lifetime and large PL intensity. PL peaking at 740 nm, 742 nm, 744 nm and 750 nm are observed from the fluorescent sensor sheet with an excitation by a laser diode at lambda=405 nm. Temperature dependence of the PL intensity ratio, 1740/1750, which increases with temperature from 300 K to 440 K, is suitable for non-contact temperature measurement