Controlled thermal design of LED SLIM TV systems

Abstract

The market trend of global TV industry is nourished due to recent advancements in optical component technology and user expectations. Due to strong market requirement for slimmer mechanical designs (<;10mm) and increased luminance (700nit), higher color gamut (DCI: 120%); Decreasing Backlight Unit (BLU) thickness while increasing the image quality resulted in a factor of 3 increase in volumetric heat generation rates. Heat generated by LED packages is the primary cause of defects and deformations in the LED TV optical components. TV manufacturers have then faced challenging thermal design issues. Therefore, the thermal design for a BLU must be well understood to develop a novel optic-thermal design. In this study, an approach for the thermal management of an LED TV system is developed to determine local temperature distribution over BLU and electronics. A hybrid analytical and CFD modeling approach followed by an experimental validation has been developed. First, an idealized one dimensional resistance network is created. Then, 3D CFD models of the LED TV are developed by utilizing commercial software. CFD results are then validated with the experimental data performed in a controlled thermal chamber. The test data is compared with CFD findings. A variation of 6.3% is found between numerical and experimental findings.