光學式自動聚焦系統之雙共軛與刀緣重心法之比較

Comparison of dual-confocal and knife’s center of gravity methods for optical autofocusing systems

楊駿億(JYUN-YI YANG)

指導教授 ： 劉建聖

國立中正大學/工學院/機械工程學系/碩士(2016年)

摘要

自動聚焦模組可以分為兩大系統，一為影像式自動聚焦模組系統，另一則是光學式自動聚焦模組。影像式自動聚焦模組是傳統的自動聚焦系統，其利用影像銳利度或者是影像空間頻率函數來計算聚焦評價函數，但其最大的缺點是反應時間太慢跟精度不足，不利於生產線上產量的提高，因此近年來逐漸被光學式自動聚焦模組取代。而光學式自動聚焦模組則是利用光感測器所偵測之光形或能量變化來計算聚焦評價函數，其優點是精度較高、反應時間較快。在要求高產量與高品質的精密生產線上，自然光學式自動聚焦模組較具優勢。
目前商用光學式自動聚焦系統以雙共軛聚焦系統與刀緣重心法聚焦系統為其主要使用類型，但兩者的系統構成要件各不相同。因此本論文首先針對此兩者光學式自動聚焦系統的系統建構參數，使用商用光學模擬軟體Zemax進行建置與優化分析，並進行相關分析結果比較，接者進行實際雙共軛聚焦量測系統建置、取樣且與模擬分析的結果進行比對。其中本論文兩光學式聚焦系統的分析比較結果，可作為未來建構此二者聚焦量測系統時的參考依據。

關鍵字

自動聚焦 ； 顯微鏡 ； 雙共軛焦 ； 三角測距

並列摘要

Existing autofocusing systems can be broadly classified as the image autofocusing and the optical autofocusing systems. The image autofocusing systems, designed as the original autofocusing system, calculate the focusing merit function with image sharpness or image spatial frequency function, causing the longer reaction time and lower positioning accuracy at the focusing point. Without reaching the proper production, the image autofocusing systems are replaced by the optical autofocusing systems, which calculate the focusing merit function with light shape/energy variety detected by a photodetector. With the quicker reaction time and higher positioning accuracy at the focusing point, the optical autofocusing systems dominate the main market.
The dual-confocal autofocusing and knife’s center of gravity autofocusing systems are current two major commercial optical autofocusing systems, but they have different constituent components. As a result, this thesis first provides a series of simulations of these two autofocusing systems with a commercial software Zemax and then performs the optimization and comparison of the results. Continued from the build dual-confocal autofocusing system prototype and sampling, we compare all the results from simulation analysis. In particular, the analysis results in this thesis will be good references for constructing these two autofocusing systems.

並列關鍵字

Autofocusing ； microscope ； dual-confocal ； triangulation

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