隨著奈微米(Nano/Micro technology)科技的進步，光電產業界不斷往省能、低成本、可攜式方向邁進，人類對於光學元件的重視日以遽增。加上半導體製程技術的突破性發展，整合光學元件形成完整的微光學系統，為了增進微光學元件的功率與效能，許多以控制微光學為基礎的技術被研究發展。其中製造微透鏡陣列(Microlens array)的方式最為快速、簡單，具有大量陣列以及輕量化的優點。
本研究微透鏡製程主要為改良LIGA-Like微成形技術，並結合擴散膜(Diffuser)與光罩製作微透鏡陣列(Microlens array)結構，我們將其稱為3D光擴散微影製程。這種光擴散方法結合光刻技術，製造出的軟性微透鏡陣列薄膜，具有高度可控(Well-control)形狀和接近100％的填充因子(High fill-factor)，這種全填充因子的表現可稱為無縫(Gapless)微透鏡陣列。
本研究是採以透光率達90%以上的聚二甲基矽氧烷(PDMS)作為微透鏡陣列的結構，PDMS可撓特性可整合在非平面元件上，達到微型化、微小化特性。對於外型的定義，透過弛垂方程式(Sag equation)擬合曲線來表示，進一步了解不同UV劑量下的外觀差異，最後對光學薄膜量測其光學性質。本研究使用雷射光束通過微透鏡陣列，觀察聚焦在焦平面的光斑點，並計算焦距與數值孔徑。結果發現隨著角度(0o, 30o, 60o)不同，光斑點(Spot)產生偏移變化，這個現象可被大量應用在光學感應器上(Optical sensor)、圖像感應器(Image sensor)。透過實驗研究與討論，本研究快速製造的微透鏡陣列，能夠有效幫助光學系統提高視角以及靈敏度。

With the increasing downscaling of electro-optical components and the development of microelectromechanical systems (MEMS), microlens array is attracting more attention for various applications, including optical communications, image processing, lab-on-a-chip techniques, high-definition projection displays and other photonic devices. Hence, many manufacture processes for microlens have been described, such as the thermal reflow, laser micromachining, gay-scale mask, ink-jet printing and proton beam writing. The variety of microlens array can usually be employed for lighting design for improving their outcoupling efficiency or enhancing the light extraction efficiency. Compared with the conventional photolithography, a diffuser approach can be used in developing a process to fabricate the microlens array. The advantages of a diffuser include a simple process and shape control of microlens array. This study presents a simple and effective diffuser approach to fabricate a plastic microlens array with controllable shape and full fill-factor, and combined the methods of the soft lithography and plastic replication.
It can be found that the microlens array of PDMS structures is an extremely high full fill-factor. The fill-factor in this study is approximately 100%. In conclusion, the full fill-factor PDMS microlens array can be successfully fabricated by a diffuser approach. The precise shape of microlens is needed by using the well-controlled process parameters. The curves of the microlens are fitted by using sag equation. Thereupon, this study can be helpful to a new route to range of functional optical applications.

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