Paper detail

Continuous spatial field confocal thermometry using lanthanide doped tellurite glass

Quantifying temperature variations at the micron scale can provide new opportunities in optical sensing. In this paper, we present a novel approach using the temperature-dependent variations in fluorescence of rare-earth doped tellurite glass to provide a micron-scale image of temperature variations over a 200 micrometre field of view. We demonstrate the system by monitoring the evaporation of a water droplet and report a net temperature change of 7.04 K with a sensitivity of at least 0.12 K. These results establish the practicality of this confocal-based approach to provide high-resolution marker-free optical temperature sensing.