在微光機電研究領域中，微型透鏡的製作已成為一門技術，並被廣泛的應用在影像成形、光通訊、和生醫微流道檢測等方面。近幾年來，開始有越來越多的人投入可調焦式微透鏡的研發與製作。可調焦式微透鏡的使用降低了光學平台自由度的需要，進而簡化系統設計及減少體積。可調焦式微透鏡的應用範圍很廣，凡舉觀察物的位置無法固定在同一位置上時，例如照相時的對焦，或欲對生醫晶片微流道上某個距離的檢體作觀察，可調焦式微透鏡都有它獨特的優點。
本研究提出一種新式固態可調焦微透鏡。結合熱致動器之設計概念，並配合適當的彈性材料PDMS作微透鏡，以普及的矽基材製程加工及點膠方式製作本研究之固態可調焦微透鏡。研究中先以有限元素分析軟體模擬不同元件設計參數，得到固態可調焦透鏡設計最佳化之趨勢。透過實際元件製作，以及量測透鏡操作特性，除驗證本研究之概念設計具有可行性之外，亦了解固態調焦透鏡之性能，並針對其弱項嘗試加以改進。目前製作出之固態透鏡，預期其焦距可從2851微米變化至1712微米；透鏡調焦之反應時間改善後約1.6秒。
本研究所提出之固態調焦透鏡兼具微小化、積體化、可單一或陣列使用、及系統整合性高等優點。文末亦提出一些下一代固態調焦透鏡之設計理念，以期達到更佳的固態調焦透鏡效能，及更寬廣的應用範圍。

Microlens fabrication is a main technology in MOEMS field, and is broadly applied to image forming, optical communication, and biotechnology. In the past few years, more and more people started to study tunable focal length mocrolens. Because of the development of tunable focal length microlens, it made simpler system designs and smaller devices volumes other than using the out-of–plane optical bench.

We proposed a new type solid tunable focal length microlens by combining thermal actuators and choose PDMS as lens material. Besides, we discussed several microlens design parameters by using finite element analysis to find out best design trend. The measurement results showed the feasibility of solid tunable focal length microlens and agreed with the simulation results. The focal length varies from 2851 micrometers to 1712 micrometers, and the response time is about 1.6 seconds.

The solid tunable focal length microlens in our study is still a prototype. We also proposed some new ideas for next generation for better performance in the end of this thesis.

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