接觸式影像掃描器中微透鏡之結構製造與模擬分析

Micorlens fabrication process and simulation analysis in contact image sensor

謝若蘭(Jo-Lan Hsieh)

指導教授 ： 蘇國棟

國立臺灣大學/電機資訊學院/光電工程學研究所/碩士(2008年)

https://doi.org/10.6342/NTU.2008.00273

摘要

影像掃瞄元件被廣泛地應用在我們生活周遭的儀器，例如印表機、傳真機及指紋辨識機，隨著市場需求量的增加，如何大量且精確的生產將變得相當重要。
接觸式影像感測器藉由 GRIN lens array 呈像後可得到一比一且正立的影像，加上他需要較短的光程路徑，使得影像掃描器元件具有體積小且重量輕的特性，但是 GRIN lens 的製作技術及材料被某些大廠商以專利保護。
我們試著利用微透鏡陣列作為接觸式影像感測器的物鏡，來達到大量且簡單的製作過程，由於微透鏡具有製程上的限制，因此有焦距長度上的極限，我們尋找兩種不同材質的折射率差組合來達到較長的焦距，且藉由適當的 aperture 來減少 cross talk 造成的誤差。
我們簡單地製作長焦距的微透鏡陣列，並將實驗上所量測到的微透鏡表面曲率特性作為模擬的參考，再利用光學模擬軟體 ZEMAX

關鍵字

影像掃描器 ； 微透鏡陣列

並列摘要

Scanning device is widely used in many function peripherals such as printer machine, facsimile machine and finger printer. With more requiring in market, replication accuracy is important in fabrication processing.
The GRIN lens array can form erect image with unit magnification, and need short length of light path. Therefore it can be applied in contact image sensor device. But the GRIN lenses are produced by silver ion exchange in a special glass and composition of the glass is protected by a patent.
This paper attempted to find out the alternative lens in CIS mould and then to analyze its image properties by simulation tools. In this study, standard photolithography was conducted for fabrication of microlens and coating an adequate refractive index material on it to achieve long focal length. Using double slits on the proper position had the same function of black resin in SLA.
From the present results of simulation analysis, the image quality was affected by the surface type (i.e. conic constant k). Finally, we suggested that perfect parabolic surface type was suitable for high MTF, large DOF and small aberration. The accuracy of controlling surface profile is very important and may be carried out by the effect of hydrophobic and hydrophilic.

並列關鍵字

contact image sensor ； microlens array

參考文獻

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