本論文旨在探討雷射激發螢光粉產生白光之光學特性。由於雷射的高同調性，因為干涉而產生的雷射光斑是無法避免的。為了深入雷射光斑對螢光粉激發白光後對色彩均勻度的影響，我們透過實驗與模擬分析，建立雷射光斑與螢光粉光學模型，探討光斑對比度與白光色差在螢光粉表面與透鏡投影後之關係。結果顯示，當雷射的光斑對比度降至10% 以下時，即可產生與完全無光斑之光源相同的色彩表現。

In this thesis, we study the optical characteristics of the phosphor converted white light excited by blue laser light source. Due to the high coherence of the laser light source, laser speckle cause by interference is unavoidable. In order to understand the influence of laser speckle on phosphor converted white light, we did a series of experiments and simulations to accurately build the phosphor and speckle model, and analyzed the relationship between the speckle contrast of laser speckle and the color difference of the white light on the surface of the phosphor and the white light projected on the screen by the collimating lens. The result shows that when the speckle contrast of the laser speckle decrease below 10%, the color performance of the white light excited by speckled light is almost the same as the white light excited by speckle-free light.

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