西元2005年由Narendran 等人所提出之散射光子萃取技術 (Scattered Photon Extraction , SPE) 被證實是一個有效的解決方案，它提供了全方向性的發光型式，有助於全周光型之設計。然而，除了出光效率之外，空間色溫均勻性亦是評價高品質白光LED不可或缺的指標。一個非優化的SPE封裝技術將導致空間白光色偏的增加，並影響實際的照明品質。有鑑於此，本論文提出三種改善空間色均勻性且兼顧光萃取效率之解決方案，分別為改變全反射透鏡之照度分佈、改善螢光粉層結構以及採用不同設計概念的透鏡來達到良好空間色彩均勻性。本論文提出的設計可同時維持高效率且縮小前後向色溫差距，其中以導光概念所設計出得結構可使正向及背向平均色溫標準差值由2720.38 K降至657.92 K，而正向及背向光萃取效率則分別為77.50 lm/W 以及80.87lm/W。

The concept of Scattered Photon Extraction remote phosphor is proven to be one of the effective solutions for improving Light Extraction Efficiency of white LEDs, and it provides the omni-direction light distribution for lamp design from Narendran in 2005. Not only the Light Extraction Efficiency is important, but also the spatial CCT uniformity is a critical index in the evaluation of high-quality white LEDs. However, an non-optimized white LED light source will induce the increase of spatial CCT deviation and induce the quality of lighting, therefore this thesis proposes three solutions to improve the spatial CCT uniformity and the Light Extraction Efficiency such as, change the different illuminance distribution of Total Internal Reflection Lens, improve the phosphor layer structure, and use the different concept of lens. The solutions are proven in this thesis can maintain the high Light Extraction Efficiency and reduce the deviation of forward and backward CCT. Among them, using the concept of light guide to design the lens can make the deviation of forward and backward CCT from 2720.38 K to 657.92 K and the forward Light Extraction Efficiency is 77.50 lm/W, the backward Light Extraction Efficiency is 80.87lm/W.

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