Dispersive Meta-lens Thermometry for High-temperature Measurements.

Temperature is a fundamental parameter that governs the rate and extent of thermal energy transfer. Accurate measurement is crucial for safe and efficient energy exchange. Radiation thermometry, favoured for high-temperature measurement due to its non-invasive nature, often requires bulky optics like interference filters. Meta-lenses, which separates incoming thermal radiation across a wide spectrum, offers a promising path toward integrated and miniaturized solutions. This work proposes a Dispersive Meta-lens Thermometry (DMT) for high-temperature measurements, employing a dispersive meta-lens with controllable dispersion to encode hyperspectral information into a compressed image. This is deciphered using convex spectral compress sensing and a deep reverse dispersive network. Experimental results show DMT achieved a 6-fold reduction in measurement error ( < 0.32%) over recent multi-spectral light-field thermometry approaches, and measurement errors for flame impingements maintained below 1.5%. No doubt further integration is required, this work demonstrates the potential for miniaturized hyperspectral high-temperature thermometry.