Chip emissivity mapping for blue and white light emitting diodes

Abstract

In order to measure the temperature distribution at the chip surface of blue and white light-emitting diodes, we used two temperature conventional emissivity measurement method, which consists in processing the thermographic signal for two uniform controlled temperatures T1 and T2. In this study, we report the evolution of emissivity with increasing temperature between 20°C and 80°C from to the ambient temperature, about 20°C.

Infrared thermography applied to the validation of thermal simulation of highluminance LED used in automotive front lighting

“…Therefore, the knowledge of temperature distribution on LED active region (or emitting area) is needed to determine the junction temperature of such optoelectronic component. Different studies have investigated the use of infrared thermography in order to obtain a quantitative heat distribution dissipated by LED [2,3]. However, this technique is limited by the knowledge of the emissivity of LED active region [4,5].…”