白光LED之YAG螢光粉光學模型之研究

The study of optical modeling of YAG phosphor for white light LED

何信穎(Hsin-ying Ho)

指導教授 ： 孫慶成

國立中央大學/理學院/光電科學研究所/碩士(2008年)

摘要

在本論文中，為了探討螢光粉於白光LED封裝之光學特性及建立準確的光學模型，我們結合蒙地卡羅（Monte-Carlo）光追跡法及米氏散射(Mie scatter)原理模擬光線於螢光粉膠體中傳遞時所造成的體散射效應。在模型中我們紀錄藍光被螢光粉所吸收的空間分佈，為螢光粉激發之黃光分佈光源。藉由藍光與黃光兩次光追跡來描述白光LED之光學行為。由實驗與模擬之驗證與分析，我們成功地建立等效YAG螢光粉之光學模型，並應用於白光LED封裝之分析，可對於自行設計之LED封裝找出最佳化結果，模擬分析其出光能量，光萃取效率，及LED於三度空間中之色溫分佈。

關鍵字

光學模型 ； 螢光粉

並列摘要

In this thesis, in order to probe into phosphor powder in the optics characteristic of white light LED encapsulation and set up accurate optics model, we combine Monte-Carlo method and volume Mie scattering effect to simulate light transmit in phosphor powder, and record of the space distribution of photon absorbed; it is the new light source that be exciting phosphor, and the optics behavior described the white light LED by blue and yellow two times of light tracing. With the verification of the experiment and simulation, we succeed in setting up the optics model of equivalent YAG phosphor, and apply to the analysis of white light LED encapsulation, can find out the optimization result to the LED encapsulation that is designed by oneself, simulation is analysed all energy happens in it, extract efficiency, and the correlate colour temperature distributed in three-dimensional space.

並列關鍵字

YAG phosphor ； optical modeling

參考文獻

[4] S. Nakamura, T. Mukai, and M. Senoh, “Candela-class high-brightness InGaN/AlGaN double-heterostructure blue-light-emitting diodes,” Appl. Phys. Lett. 64, 1687-1689 (1994).

[5] S . T. Flock, B. C. Wilson, and M. S . Patterson, “Total attenuation coefficients and scattering phase functions of tissues and phantom materials at 633 nm.” Med. Phys. 14, 835-841 (1987).

[6] L. G. Henyey and J . L. Greenstein, “Diffuse radiation in the galaxy,” Asrrophys. J . 93, 70-83 (1941).

[7] Optoelectronics Industry Development Association (OIDA). Light emitting diodes (LEDs) for general illumination: An OIDA technology roadmap update 2002. Optoelectronics Industry Development Assn., Washington DC, 2002.

[9] A. Zauskas, F. Ivanauskas, R. Vaicekauskas, M. S. Shur and R. Gaska, “Optimization of mulitichip white solid state lighting source with four or more LEDs,” Proc. SPIE 4445, 148 (2001).