Optical interference system for measuring thickness and refractive index of slim transparent plate

• Main Authors: CHEN,CHUN-LIN, 陳俊霖
• Other Authors: LIU,CHIEN-SHENG
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/7z3b5j

碩士 === 國立中正大學 === 機械工程系研究所 === 107 === In this thesis, we design a novel optical interference system for measuring thickness and refractive index of slim transparent plate with two optical paths. In the structure of the proposed optical system, the laser beam passing through the sample is affected by the thickness and refractive index , which causes a change in the optical path difference from the reference beam and the measuring beam to the sensor, and then calculate sample parameters (refractive index n, thickness d) by using the different optical path difference variations of two optical paths. Also, we verify the feasibility of the proposed optical system with qualitative and quantitative analysis respectively. In the qualitative analysis, the architecture of the proposed optical system is established in the optical simulation software ZEMAX to observe the characteristics of the proposed optical system. In the quantitative analysis, to accurately and efficiently analyze the relation between interference fringe information and the individual thickness d and the refractive index n, the optical path difference is calculated by interference fringe.