Study on the optical performance of light guide plate with pyramid-shaped microstructures

Abstract To improve the optical performance of light guide plate (LGP), pyramid-shaped microstructures on the bottom surface of LGP were developed to obtain much higher light utilization and luminance uniformity. Firstly, the edge-lit back-light module (BLM) was designed by LightTools according to the light transmission principle. Secondly, the pyramid-shaped microstructures were arranged on the bottom surface based on the distribution law, and the optical performance was compared with traditional spherical microstructures. Then, the effect mechanism of the pyramid-shaped microstructure parameters on light utilization and luminance uniformity was well summarized. Combined with the above analysis, the microstructure distribution was simulated and optimized, and a high-precision pyramid-shaped microstructure array was processed on the bare surface of LGP by femtosecond precision manufacturing system. Finally, the optical test showed that the average luminance and luminance uniformity of the LGP were 2352.8 cd/m2 and 92.4% respectively, which met the national lighting standards and industrial application requirements.