繞射/折射複合型變焦鏡組之設計與量測

Abstract

本論文中，我們描述變倍比為3倍被使用在數位相機上之緊湊三群透鏡變焦系統的設計流程，此系統被要求不僅有小的體積和重量，而且有足夠長的後焦以便在成像面前放置彩色濾波片。 首先我們將系統中的透鏡分為二群，即所謂的二鏡組設計方法來找到變焦系統的高斯解。在這個高斯解當中，第一群透鏡是由二個透鏡所組成，但第二群透鏡只包含有一個透鏡。 在這高斯解的基礎上，然後我們藉由光學設計軟體ZEMAX來設計此變焦系統。在這變焦系統中，我們為了優化每一個透鏡的效能，則我們將每一個透鏡替代為繞射/折射混合型透鏡，在此透鏡系統設計中，每一透鏡的表面均是非球面，在這同時我們也建立利用MATLAB做為平台的一套軟體，根據從光學軟體ZEMAX模擬的結果來計算在混合型透鏡繞射表面上的波帶(或信息圖)結構，對於所設計的混合型透鏡已經由工業技術研究院的機械研究所，利用鑽石車床加工製作完成。變焦系統的幾何和光學特性則在我們的實驗室所測得，所測量的結果與結果的分析將被描述。

In this thesis we described a procedure for design of a compact three-lens zoom system used in digital camera with a zoom ratio of 3. This system is required to have not only small size and weight but also long-enough back focal length in which a color filter can insert. First we found a Gaussian solution of the zoom system with so-called two-optical-component method, in which the lenses in the system are divided into two groups. In this solution the first group comprises two lenses, but the second group contains only one lens. Then, based on the Gaussian solution, we designed the zoom system with the optical software ZEMAX. In order to optimize the performance of each lens, we replaced each lens with a diffractive/refractive hybrid lens. In this design all surfaces of lenses were aspherical. At the same time we built a software with MATLAB for calculation of the kinoform structures of diffractive surfaces on the hybrid lenses according to the results from ZEMAX. All the designed hybrid lenses have been fabricated with diamond turning by Mechanical Industry Research Laboratories of ITRI. The geometric and optical properties of the zoom system were measured in our lab. The measurement results and an analysis on these results are described.