Design and Application of Freeform Surface in Optical System

• Main Authors: Yi-Hsien Chen, 陳乙賢
• Other Authors: Guo-Dung Su
• Format: Others
• Language: en_US
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/13289069038493311404

碩士 === 國立臺灣大學 === 光電工程學研究所 === 97 === An optical system means a system consisting of many different optical elements for handling light. Lenses are typical optical elements in optical systems. Most lenses are spherical lenses. However, for some purposes, such as decreasing optical aberrations, reshaping beam profiles, combining different optical power in a single lens, and etc, spherical lenses are not appropriate. We have to design a specific lens to bend rays into the directions we set, and then the surfaces of the lens are usually aspherical surfaces and even freeform surfaces. Along with the progress of computers and technology of manufacture, it is feasible to design specific lenses with freeform surfaces. In this thesis, there are four topics. The first topic is about an infrared optical system used to detect the gases inside the high-vacuum glass panels. The second topic: progressive addition lens (PAL) is a significant example of freeform surface design. Progressive addition lenses are used to treat presbyopia. We use the finite difference method to analyze PALs and the direct method to design PALs. In the third topic, we discuss an optical system used to reshape the laser beam effectively. In the final topic, we introduce an optical system which can homogenize the LED light.