我們利用兩層材料分別為二氧化矽與二氧化鈦的均質抗反射層加上一維三角形光 柵的結構，設計出一具有寬頻譜及廣角效果之抗反射層。垂直入射時，平均穿透率 (Tsolar)可達到 99%，八十度入射時，平均穿透率能維持在 94%左右。
設計原理為由於均質抗反射層無法提供廣角的抗反射效果，因此我們在均質層上外 加一維三角形光柵的抗反射設計，欲使整個結構達到寬頻譜及廣角的抗反射效果。利用 比較垂直入射與八十度入射之平均穿透率(Tsolar)值，我們獲得三角形光柵結構的最佳 光柵參數，光柵高度為 0.6um、光柵週期為 0.6um 與光柵填充率為 0.125。其中三角形 光柵提供了繞射現象與等效折射係數漸進的效果，成功的降低了均質抗反射層的高角度 靈敏度。經過探討光柵形狀與光柵下方的均質層層數對穿透率的影響，發現三角形光柵 相較於方形光柵與弦波狀光柵，具有在大角度入射下之較高的穿透率頻譜，及此光柵結 構必須與均質層組合才能達到高穿透率的效果，其中兩層均質層與一維三角形光柵在此 最佳化參數下達到最佳的抗反射能力。
從本論文中可知道均質層加上最佳化的一維三角形光柵的結構即達到相當好的寬 頻譜與廣角的效果，其中均質層的結構可利用鍍膜的方式來製作，一維光柵的結構可利 用雷射干涉術[20]或非等向性蝕刻[21]來製作出一維三角形光柵。然而這兩種方法都具有其 缺點存在。雷射干涉術較難製作出完整三角形的光柵形狀，只能製作出近似三角形光柵
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的形狀來替代。非等向性蝕刻製程不能做出任意角度的三角形光柵。所以雖然從模擬的 數據上可看到非常好的抗反射能力，但以製程的眼光來看，此一維三角形光柵的製程具 有一定的難度。
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