微透鏡陣列(Micro Lens Arrays, MLA)被廣泛使用於各領域，本研究利用數位光處理（DLP）技術搭配灰階數位光罩，透過調整像素的灰度值，精確調節曝光能量，單個像素大小為5 μm，達到高速製造微透鏡陣列的效果，同時導入失焦法，透過偏移DLP系統中聚焦鏡頭的位置，消除微透鏡表面的階梯效應，降低微透鏡表面粗糙度。DLP製程利用數位光罩曝光樹脂，能透過調整曝光能量、失焦距離、光罩直徑等參數，調整微透鏡陣列的形貌。這使得能夠根據不同需求生產各種特性的微透鏡陣列，例如高數值孔徑、特定曲率、高解析度和高填充因子等。本研究亦使用新開發之光固化樹脂，其成型特性及光學性能較以往使用的泛用型樹脂更符合製造微透鏡陣列的需求。為了能快速設計微透鏡陣列的形貌，研究中開發一基於Python語言之人工智慧（Artificial Intellegence, AI）演算法，用於輸出指定形貌微透鏡陣列之對應灰階數位光罩，以實現迅速設計和製造具非傳統輪廓的微透鏡陣列。本研究進行了各種實驗以探討DLP系統曝光能量和失焦法對微透鏡形貌之影響，比較新開發樹脂和舊有樹脂在機械性質和光學性質方面的差異，並測試AI演算法設計的微透鏡陣列，其實際形貌和光學性能與理論值之誤差。實驗結果顯示本研究製程可於10分鐘內完成微透鏡陣列之製造，且微透鏡陣列的高度與曝光能量成正比。所製造之微透鏡陣列表面粗糙度(Sa)最低為52 nm，解析度最高為65.9 lp/mm，這相當或優於具有55 lp/mm解析度的商業塑膠微透鏡陣列，數值孔徑最高為0.98，填充因子最高77.98%，而微透鏡直徑最小為60 μm。搭配AI演算法設計微透鏡陣列，本研究製程可製造具多焦距（從21 μm到199 μm）、廣視角及非球面形貌之微透鏡陣列。本製程具有環保(積層製造而非減法加工)、高設計自由度（無需實體光罩或模具）和低成本（每個MLA材料成本小於新台幣100元）等優點，本研究的AI演算法被認為是「殺手應用」。所提出的製程和AI演算法的結合具有相當的潛力，非常適用於工業中微光學裝置的原型開發。

In this study, digital light processing (DLP) technology was used in conjunction with grayscale digital masks to achieve the rapid production of micro lens arrays. The defocus method was also introduced to eliminate the step effect on the surface of the micro lenses by shifting the position of the focusing lens in the DLP system, reducing the surface roughness of the micro lenses. The study also employed a newly developed photocurable resin, which, compared to the generic resins used previously, better meets the manufacturing requirements of micro lens arrays in terms of molding properties and optical performance. In order to quickly design the morphology of micro lens arrays, an Artificial Intelligence (AI) algorithm based on the Python language was developed in the study to output corresponding grayscale digital masks for specified morphology of micro lens arrays, enabling the rapid design and production of micro lens arrays with non-traditional profiles.
Various experiments were conducted in this study to investigate the effects of DLP system exposure energy and the defocus method on the morphology of the micro lenses. A comparison was made between the newly developed resin and the existing resin in terms of mechanical properties and optical properties. The microlens arrays designed by the AI algorithm were tested for the discrepancy between their actual morphology and optical performance and the theoretical values.The experimental results showed that the manufacturing process in this study can produce micro lens arrays within 10 minutes, and the height of the micro lens arrays is directly proportional to the exposure energy. The surface roughness (Sa) of the manufactured micro lens arrays was as low as 52 nm, with the highest resolution being 65.9 lp/mm, which is comparable to or better than commercially available plastic micro lens arrays with a resolution of 55 lp/mm. The highest numerical aperture was 0.98, the highest fill factor was 77.98%, and the smallest micro lens diameter was 60 μm. By using the AI algorithm to design micro lens arrays, the manufacturing process in this study can produce micro lens arrays with multiple focal lengths (ranging from 21 μm to 199 μm), wide field of view, and aspherical profiles. This process has the advantages of being environmentally friendly, high design flexibility, and low cost. The AI algorithm developed in this study is considered a "killer application." The combination of the proposed process and the AI algorithm has considerable potential and is highly suitable for prototyping micro-optical devices in the industry.

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