Simulation and Experimental Analysis of Molding Processes of Glass Diffractive Optical Elements

• Main Authors: Yu-Kun Chen, 陳育琨
• Other Authors: Choung-Lii Chao
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/31900770848009258856

碩士 === 淡江大學 === 機械與機電工程學系碩士班 === 99 === In comparison to conventional refractive lens, diffractive lens has the advantages of being thinner and lighter, and is widely used in optical systems such as lighting and photovoltaic systems. The big majority of the concentrators used for concentrated photovoltaic (CPV) energy today are made of plastics, for its superb formability, light weight and cheap price. However, plastics do have the setback of aging and degradation when subject to ultra-violet exposure. Glass, on the other hand, being heavier and more expensive than plastics, can sustain the UV light without any trouble. To get around these problems, diffractive lens and glass molding process (GMP) are selected in this study to reduce the weight and cut the cost. Simulations together with molding experiments were conducted to analyze the stress/strain conditions and the obtained dimensional accuracy under various molding parameters. Results show that parameters such as mold designs, molding conditions and pre-form designs all have profound influence on the achievable dimensional accuracy and the obtained maximum stress/strain. Simulation can effectively improve the outcome of molding experiments by supplying the correlation between molding parameters and resulting stress/product shape. Glass DOEs of 14.8 mm in diameter and 3.36 mm in thickness are successfully produced in this research and the difference between the simulated and the molded DOE is around 15μm.