本論文旨在提出將橢面透鏡置於光纖端面上，並利用透鏡的聚光特性，增加半導體雷射光強度於光纖之光訊號耦光效率，以減少光纖光訊號之對位損失。首先採用光學模擬軟體，模擬橢面透鏡對於光纖的耦合效率。利用田口品質工程法，將影響光耦合之各種參數中找出最佳參數值，並以該參數值做出符合模擬結果之光纖橢面透鏡輪廓。接著微影製程研製橢面微透鏡之模仁成型，隨即將橢面光阻透鏡進行微電鑄，得到橢面微透鏡凹模，再以PDMS為母材得到該橢面微透鏡。最後利用Epoxy使與橢面微透鏡與光纖黏合，達成於光纖端面具橢面微透鏡之目的。因此製程開發可開啟光纖微透鏡之量產化濫觴，並驗證其橢面微透鏡光耦效率可達42.7%。
於此利用波動光學繞射理論作為半導體雷射與光纖耦光數學模型，根據此模型。可計算出光耦合效率、光纖對位容許度與光纖對位偏移容許度；並利用該模型之相關參數，將半導體雷射之橢圓場型經由橢面微透鏡轉換為圓形場型。而其最佳理論光耦合效率可達77%，且其光纖對位容許較現有光纖微透鏡製程有較低靈敏度，因而可提升光纖對位之製程良率。因橢面微透鏡製程開發加以理論推導，得以加以設計而成光纖微透鏡連接器模組化。

This article demonstrates the effective coupling between a single- mode fiber (SMF) and an edge emitting laser diode (LD) using an ellipsoidal microlens on the tip of the SMF. The optical simulation software “TracePro” and the “Taguchi method” were used to search for the optimal lens design and coupling efficiency parameters for the LD to SMF. The ellipsoidal microlens was fabricated using photolithography, thermal reflow, mold electroforming and polydimethylsiloxane (PDMS) injection. UV-curing glue was then smeared and exposed to fasten the lens onto the fiber. Through those processes, the end of optical fiber will have an ellipsoidal microlens for LD to fiber coupling. Due to the process developed, it is suit for mass production for microlens on the end of fiber. And the coupling efficiency of LD to SMF can achieve to 42.7%.
A scalar diffraction analysis was used to calculate the coupling efficiency and align tolerance. Due to the phase transformation caused by the ellipsoidal microlens, the field distribution pattern of laser diode will change from elliptic to circle. Form this theory analysis, the optimal design for coupling efficiency can achieved to 77% and with a high alignment tolerance than the other methods for fiberlens. Per the microlens processes developed with theory analysis, it may design a fiberlens connector module for LD to SMF coupling.

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