目前光學式自動對焦模組在光斑的影像處理部分常會遇到因為系統組裝誤差、環境雜訊等因素，使得無法用簡單的尋圓方法來描述光斑之各種資訊，而本實驗室之自動對焦技術雖已有數年之研究基礎，然而卻有系統架構龐大、控制程式無法整合等缺點。
本論文以既有的自動對焦架構為基礎，開發出一套能夠快速計算出光斑理想橢圓中心及有效補償因各種誤差造成的對焦特徵曲線不夠線性的演算法，利用這個演算法，無論是長行程或是短行程的自動對焦架構之精度及速度均能有效提升，最佳精度可低至1 μm以下。
本論文亦基於方便操作、簡明扼要與美觀等產品化的因素重新編寫使用者介面，結合新提出的演算法，開發出一套整合馬達控制、自動對焦與即時監測的控制軟體。最後再將光路整合至一110 mm × 80 mm × 80 mm方盒結構中，完成系統光路模組化，為產品化鋪路。

At present, the image processing part of optical autofocus modules often have various factors, which make it impossible to describe the image information of the semi (elliptical) circular speckle with a simple circle-finding method. Although lots of domestic institutions have been researching in optical autofocusing field for several years, there are disadvantages such as huge system architecture and difficulty in integrating system control programs.
This thesis has developed a set of algorithms that can quickly calculate the ideal ellipse center of the spot and effectively compensate the linearity of the focusing characteristic curve. By using the proposed algorithms, the autofocusing accuracy and speed can be effectively improved, and the best accuracy can be as low as 1 μm.
In addition, the user interface has been rewritten from the user's point of view, combined with the newly proposed algorithm and a set of control software that integrates motor control, autofocus and real-time monitoring has been developed. Finally, the optical system has been miniaturized into a 110 mm × 80 mm × 80 mm box to complete the system modularization, paving the way for future productization.

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