Phosphor Thermometry at ORNL

Phosphor materials are, by design, capable of efficiently converting excitation energy into fluorescence. The temperature‐dependent characteristics of this fluorescence provide the basis for noncontact thermometry. In the past decade this approach has been applied to turbine engine diagnostics, liquid temperature measurements for heat pump research, combustion engine intake valve and piston measurements, galvanneal steel processing, transient thermometry of particle beam targets, and microcantilevers used in MEMS devices. The temperatures involved range from ambient to in excess of 1200 °C. Some of these applications have involved fiber optics for light delivery and/or fluorescence signal collection. In addition to fielding these applications, there has been considerable work in the laboratory aimed at exploring further improvements and adding to the database of temperature‐characterized phosphors. The activities involve investigation of short‐decay time phosphors for use on imaging surfaces moving at hig...