隨著資訊的發展及影像處理的的需求，微小化、高密度積體化已經成為現行光電系統發展的主流，其中，被視為最可行的技術是整合式的微光電系統，此技術將光發射、光傳輸或光接收元件整合於微小的系統裡，除可降低成本外，亦可有效提高效能。
本論文提出兩種新型且易於整合之折射式直立微透鏡製程，其主要原理是利用高分子在高溫時內聚的物理現象製作，利用這兩種製程可製造出表面相當平滑之球面微透鏡，並且這些製造出的微透鏡皆有相當高的數值孔徑值(NA)，可有效聚焦高度發散之光束。經由研究證實，發散角相當大的邊射型雷射(edge-emitting laser diode)，其發散角由原來大於四十度經過微透鏡後角度收歛變為低於五度，這將有效增加雷射光耦合至單膜光纖耦合率(coupling efficiency)，我們相信，這兩種折射式直立微透鏡除了可用於光通訊系統外，亦有利於其他微光電平台(optical bench)之建構。
除此之外，鑒於現行封裝技術光纖光源耦合至高速檢光器(Photodiode)表面之嚮應區(active region)效率低，而且需要昂貴、高精準度之對準設備，我們在本論文中亦提出ㄧ種整合微球透鏡(micro-ball-lens)之高速檢光器，藉由聚焦光源至嚮應區而提高耦合率及光纖對準的容許範圍。研究證實，在整合250微米(□m)的紅寶石(ruby)微球透鏡後，相較於單一高速檢光器，光纖對準的容許範圍提高了7.1×10倍，對於現有封裝技術而言，這將是一大利多。
附帶一提的是，上述微光電系統的建置及優化，是由我們所撰寫的蒙地卡羅光追跡法(Monte-Carlo ray trace)完成，這也是本論文研究重點之ㄧ。

Integrated micro-optical/optoelectronic system provides a promising approach that multiple and functional optical elements can be integrated on a single chip. As compared to the conventional optical/optoelectronic systems, the size, weight, assembly, adjusting time, and cost of the integrated systems are greatly reduced.
In this dissertation, two novel and simple fabrications of refractive vertical microlenses were demonstrated. The microlenses are spherical-shaped and have very high NA value after the reflow processes. As proven, the beam emitted from an edge-emitting laser diode with high divergence angle (θ = 40□) was successfully converged to less than 5□. These vertical microlenses will find their potential in the micro-optical/optoelectronic systems. Another micro-ball-lens integrated InGaAs p-i-n high speed photodiode is also proposed to enlarge the alignment tolerance. According to the results, as we integrate a d = 250-um ruby micro-ball-lens on the photodiode, the alignment tolerance will be 7.1-fold * 10-fold to the bare chip without microlens. Such wild alignment tolerance would be a great improvement for the package technique nowadays.
In addition, with the Monte-Carlo ray trace simulation, we can predict and optimize the performances of these refractive microlens integrated optical systems.

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