Optimal Design of LED Backlight Unit with Double-Triangular Structure Using a Genetic Algorithm

A large size direct LED BLU consisted of double-triangular structures to control the light from RGB side emitting LEDs without the indispensable optical elements for the conventional direct LED BLU, such as the brightness enhancement film, diffuser sheet, and diffuser plate was proposed. A genetic algorithm was used in this paper to search the optimal parameters of the shape of the double-triangular structures and the layout of the LEDs to obtain optimum optical performances. Without diffuser and BEF, brightness uniformity of 91.87%, color uniformity of 0.042 and on-axis brightness increase of 50.23% for 22" direct LED backlight unit with a thickness of 30 mm with optimized double-triangular structure was obtained.