Simulation and analysis of light extraction and directionality for LEDs with micro structures

• Main Authors: Shang-yu Tsai, 蔡尚祐
• Other Authors: Ching-cherng Sun
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/99724718366220512002

碩士 === 國立中央大學 === 光電科學研究所 === 97 === In this thesis, we build the optical model for photon recycling effect of LEDs based on Monte Carlo ray tracing method. According to this model, under different absorption coefficients of the active layer, we analyze the light extraction efficiency with respect to GaN and AlGaInP LEDs. Furthermore, we select two kinds of GaN LED structures such as surface texture of ThinGaN LEDs and patterned substrate of sapphire-based LEDs. Based on these two structures, we analyze the enhancement of the directionality and the light extraction efficiency when the slanted angles of the pyramid array are different.