本論文研究重點在於設計與製作微球透鏡陣列並且應用於光纖耦合，由別於一般平凸透鏡的應用(與基材垂直) ，球透鏡適合用於水平任何方向的傳輸更有利於光纖通訊、光儲存系統、生醫科技。
本實驗採用SU-8製作為球透鏡，並以一低溫製程製造微球透鏡陣列，先在晶圓上旋塗SU-8 ( 30µm) 且利用黃光製程做出微圓孔，再利用體型微加工背後蝕刻的方式將晶圓吃穿成為噴嘴結構，再將SU-8填入噴嘴後以擠壓的方式將SU-8擠出，最後因表面張力即內聚力的平衡而形成微球透鏡，其直徑控制於擠壓量的多寡。

目前本研究所完成24X24的微球透鏡陣列，其數值孔徑約為0.63，微球透鏡直徑大小由80~500µm，焦距長度為50~300µm，經量測結果同批生產的直徑誤差約在3%，而每次製作的誤差約在10%，主要的誤差來源是施力的不均勻。

This paper presents a ball type microlens array for optcal fiber coupling. In contrast to conventional microlenses made in a half-spherical geometry, the ball type microlens is a sphere which allows light focusing in all directions on the substrate surface and thus provides the flexibility for fiber coupling in applications of optical communication, optical storage system, and biomedical instruments.
The present microlens is made of photoresist SU-8. We have developed a low temperature batch process by spin-coating SU-8 on a silicon wafer. The thick SU-8 film is patterned by UV lithography to form an array of holes for holding micro-balls. Bulk machining is then applied to formulate an array of nozzles on the wafer. Molten SU-8 is poured onto the wafer and pressed through the nozzle. Micro-balls are formed by a balance between surface tension and cohesion. The diameter of balls is controlled by varying the amount of SU-8 pressed through the nozzle.

In the experimental stage, we have formulated a pattern for a 24 x 24 lens array and can produce micro-balls with numerical aperture about 0.63. Diameters range from 80 to 500μm and focal lengths range from 50 to 300μm. Measurements indicated that the fluctuation of the diameter was within 3%; variations among batches are within 10%. The major contribution to the uncertainty is due to the variation of the pressing force.

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