A Microscopic Hyperspectral-Based Centroid Wavelength Method for Measuring Two-Dimensional Junction Temperature Distribution of LEDs

In this letter, we propose an experimental method for determining two-dimensional (2D) junction temperature distribution of light-emitting diodes (LEDs) using microscopic hyperspectral-based centroid wavelength. The 2D centroid wavelength matrix is extracted from the hyperspectral data cube as temperature sensitive optical parameters (TSOP), which is linearly calibrated by short pulse voltage signal in order to eliminate the influence of self-heating effect. The 2D junction-temperature distributions of LEDs under working conditions are derived by TSOP matrix. The comparative experiments by micro-thermocouple ( $\mu $ -TC) and IR imaging reveal good coincidence in both averaged temperature and temperature distribution trends.