本研究中以單模光學軟性電路板設計適用於4通道 × 25-Gbps 單模光學連接收發模組光學系統，此系統整合了高分子聚合物波導、分布式回饋雷射、微透鏡、45˚微反射面、光檢測器及12芯光纖陣列。
以Lumerical Inc.所開發的FDTD模擬軟體，應用傅氏光學的技巧來模擬雷射經過透鏡耦合至波導的成像行為。在波導設計引入S型彎曲波導波導使750 μm通道間隔的分布式回饋雷射經過S型彎曲波導波導後扇入至250 μm通道間格，使其可與常規250 μm的單模光纖陣列偶合。於光學模擬中得到發射端由分布式回饋雷射，經過微透鏡後，聚焦耦合進入單模高分子聚合物波導中，經過S型彎曲波導波導後耦合至單模光纖的光學耦合效率達41.8%，反射回雷射僅0.8%。
此光學系統之藉由主動對準方式使分布式回饋雷射與高分子聚合物波導間的位置誤差在最高光學效率降為-1 dB時，偏移容忍度分別為>  40 m以上，透鏡於最佳偶合位置偏離光軸之偏移容忍度為 0.7 m。

This study proposed a single mode 4 channel  25-Gbps optical interconnect module basing on single mode flexible printed circuit board (FPC). The polymer waveguide (PWG), distributed feedback laser diode (DFB LD) , micro lens, 45 micro-reflector, photodiode, and 12ch single mode fiber array were integrated in this module.
Simulation Software is Lumerical FDTD. We applied fourier optics technique to simulate the DFB LD coupling to PWG via micro lens. In PWG design, we adopt the S-bend waveguide to Fan-In the channel pitch. The simulation of optical coupling efficiency is 41.8 % from the DFB LD to single-mode fiber (SMF).
The optical system is 1-dB alignment tolerances of DFB LD and PWG are more than 40 m. The lens shift from optical axis is 0.7 m.

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