Thermal Characterization of Luxeon Star White LED on Plastic Heat Sink: Face and Rear Back Analysis via Digital Thermocouple and Thermal Imaging Camera

Abstract

Effective thermal management is critical for the performance and lifetime of light-emitting diodes (LEDs), as high temperatures can damage performance, shorten lifespan, and diminish light output. The purpose of this study is to analyse and evaluate the thermal behaviour of the Luxeon Star White LED at both the top and back surfaces under different driver currents (100, 200, 250, and 300mA). The thermal behaviour was assessed using digital thermocouples and thermal imaging cameras, with temperature readings recorded over a 120-minute period. The findings show that the rear back surface consistently has lower temperature rises than the top surface, indicating more effective heat dissipation. At a driver current of 300 mA, the thermal resistance for the top surface was much higher (about 263.3°C/W) than the rear back surface (about 60°C/watt). Furthermore, running the LED at lower driver currents (100mA) resulted in the smallest temperature increase, showing negligible thermal stress. These findings highlight the need of optimizing heat management solutions for various LED surfaces. The study identifies the rear back surface as a vital region for improved cooling solutions and proposes that lower running currents can greatly reduce thermal stress, improving LED lifespan and performance. This study adds to our understanding of LED thermal behaviour, guiding the development of more efficient heat sinks and cooling methods to progress LED technology and applications.