利用分離式螢光粉與沿晶塗佈螢光粉製作之白光發光二極體之光學特性探討

Abstract

本篇論文將著重討論於應用於白光發光二極體內的螢光粉層，藉由探討單一螢光粉片之發光特性，以了解螢光粉層於封裝體中之光學特性。 第一部分，我們將製作螢光粉片並了解其各角度入射之激發光場，爾後希望藉此激發光場，研究其是否能適用於各種形式之封裝體，進而建立螢光粉片的發光模型。建立螢光粉片之發光模型後，使用分離式螢光粉與沿晶塗佈螢光粉封裝體驗證本模型，並分析分離式螢光粉與沿晶塗佈螢光粉封裝體之光學特性，解釋兩者有不同色溫分佈之原因，源自於兩者在藍光大角度的強度分佈不同。 第二部分，鑒於分離式螢光粉封裝體有比沿晶塗佈螢光粉封裝體較差的變角度色溫分佈表現，且藉由上一部分所分析出的原因進行改善，我們提出了一種圖形化分離式螢光粉分佈封裝體，藉由此結構中的透光區域提高藍光於大角度的萃取效率，達到改善分離式螢光粉之色溫分佈。

In this thesis, the phosphor layer of white light-emitting-diodes (LEDs) was systematically investigated. In order to comprehend the optical characteristic of phosphor layer in packages, the emission distribution of phosphor film would be investigated first. In first section, a phosphor film would be manufactured and measured by angular-dependent excitation to obtain the emission distribution of the phosphor film. Through the emission distribution of phosphor film, the emission model of phosphor film could be established. This emission model also agreed with the emission characteristics of remote and conformal phosphor LED. Furthermore, the poor angular-dependent CCT distribution of remote phosphor, caused by the low intensity of blue light at large angle, could be clarified. Second, the cause of poor angular-dependent CCT distribution of remote phosphor was investigated in first part. In order to improve the blue light intensity of remote phosphor at large angle, the patterned structure of remote phosphor was designed. The angular-dependent CCT distribution of remote phosphor could be improved through the window region of patterned structure.