Thermal analysis of high power red light emitting diodes

In the 21st century, LEDs have been widely used in various fields, but due to the low external quantum efficiency, the junction temperature of LEDs is easily increased, and the increase in temperature will have a serious impact on the performance parameters of LEDs. Therefore, The research on the junction temperature and thermal resistance of LEDs is crucial for optimizing the performance of LEDs and improving luminous efficiency. In this paper, the forward voltage method is used to measure and calculate the junction temperature and thermal resistance of red LEDs. The junction temperature and thermal resistance of the LED were measured under the conditions of thermal silica gel and non-thermal silica gel with different heating currents. The result shows that the thermal silica gel can fill the gap between the LED and the constant temperature bath, reduce the generation of thermal resistance. The junction temperature and thermal resistance of the red LEDs increase with the increase of the driving current.