- 學位論文
可形變鏡面於自動對焦光學系統之控制方法
The Controlling Method of Deformable Mirror used in Auto-focusing Optical System
摘要
照像手機已經成為現今手機市場的主流。因為照像手機的容易取得以及普遍性，許多人會使用照相手機來拍攝一些生活中令人難忘的畫面，現今照像手機所使用的照相模組也因此不斷的進行改進期望達到更好的成像品質以及更小的體積，為了提高照相模組的拍攝品質，許多的電子功能都會搭配於照相模組之中，例如:自動對焦、影像縮放、以及電子白平衡，而在這些電子功能當中，又屬自動對焦最為基本及普遍。 傳統的照相模組是採用移動模組內透鏡的方式來改變整個系統的焦距，而移動透鏡的方式則是會利用馬達來調整透鏡相對於CCD感測器的位置，而成像的對焦程度也會因此產生變化。雖然這種移動透鏡的方式在現行的自動對焦照相模組中最為盛行，但是這種模組卻因為必須預先保留透鏡移動的空間而造成整體模組的體積難以縮小。 在這篇論文中我們提出了一種採用可行變鏡面來改變整體模組的焦聚的方式來實現自動對焦的功能，並且根據這個可行變鏡面的物理及光學特性來設計整個模組及控制的方法。其中控制的方法是根據計算影像對焦程度以及搜尋影像對焦成度最大值的演算法來進行程式的撰寫，最後，我們會實際利用LabVIEW®和MATLAB®這兩個程式撰寫平台來設計出一套自動對焦系統，用來控制這個利用可行變鏡面來變焦的光學模組。
並列摘要
Camera phones are the main stream of today’s mobile phone market. Because of the generality and accessibility of camera phones, people usually use camera phones to record the rememberable moments of their life instead of digital cameras. The camera modules that are used in camera phones are improved to have better image quality and smaller size. There are lots of electronic functions, such as auto-focusing, zooming, and white-balance, that are armed in today’s camera phones in order to provide better image quality. Among these electronic functions, auto-focusing is the most common and basic one. Conventional optical design in auto-focusing camera modules adopts the way that moving the lens to adjust the focal length of the whole camera module. Motors are attached in camera modules to change the position of lens, which will alter the image sharpness of the image that formed on the CCD sensor. Although the moving-lens method is the most popular fashion of auto-focusing camera modules, the size of the whole module is hard to reduce. This problem stemmed from the reserved space in which lens is moved. The broader variation of module’s focal length, the longer space has to be reserved. Thus, it seems hard to look after miniaturization and image quality of conventional auto-focusing camera modules. In this thesis, we discuss an innovative optical design of auto-focusing camera module, which use deformable mirror to adjust the focal length of the whole module. Besides, based on the physical and optical properties of deformable mirror, the controlling method, which is according to the principles of image-sharpness computation and searching algorithm, is explained in this research. Finally, we experimentally demonstrated the controlling method of this auto-focusing optical system using LabVIEW® and MATLAB®. As a result, an innovative auto-focusing camera module has been designed, prototyped, and controlled.
參考文獻
延伸閱讀
- Liu, C. W. (2008). 可形變鏡面在反射光學系統的應用：自動對焦與光學變焦系統 [master's thesis, National Taiwan University]. Airiti Library. https://doi.org/10.6342/NTU.2008.01817
- Wang, J. L. (2007). 可形變鏡子應用於簡潔成像系統之自動對焦與變焦 [master's thesis, National Taiwan University]. Airiti Library. https://doi.org/10.6342/NTU.2007.02138
- 陳泓餘（2015）。控制變焦鏡頭的軌跡及非球面形狀之研究設計〔碩士論文，國立中央大學〕。華藝線上圖書館。https://www.airitilibrary.com/Article/Detail?DocID=U0031-0412201512090969
- 沈信宏（2009）。Development of Micro-resonator and Dual-function Optical Device Using the DRIE/SOI Process〔碩士論文，國立臺灣大學〕。華藝線上圖書館。https://doi.org/10.6342/NTU.2009.02075
- 黃柏融（2014）。Making low actuation-voltage deformable mirror by ionic polymer metallic composite〔碩士論文，國立臺灣大學〕。華藝線上圖書館。https://doi.org/10.6342/NTU.2014.00946