Jen-Yu SHIEH, Luke K. WANG¹, and Shih-Ying KE²

Department of Electro-optics Engineering, National Formosa University, Hue-Wei, Yue-Ling County 632, Taiwan
¹Department of Electrical Engineering, National Kaohsiung University of Applied Sciences, Kaohsiung 807, Taiwan
²Glory Science Co., Ltd., Hemei, Changhua County 50843, Taiwan

(Received August 6, 2008; Accepted June 24, 2009)

A computer aided engineering (CAE) tool-assisted technique, using Moldex3D and aspheric analysis utility (AAU) software in a polycarbonate injection molding design, is proposed to manufacture large diameter aspheric plastic lenses. An experiment is conducted to verify the applicability/feasibility of the proposed technique. Using the preceding two software tools, these crucial process parameters associated with the surface profile errors and birefringence of a molded lens can be attainable. The strategy adopted here is to use the actual quantity of shrinkage after an injection molding trial of an aspherical plastic lens as a reference to perform the core shaping job while keeping the coefficients of aspheric surface, radius, and conic constant unchanged. The design philosophy is characterized by using the CAE tool as a guideline to pursue the best symmetry condition, followed by injection molding trials, to accelerate a product's developmental time. The advantages are less design complexity and shorter developmental time for a product.

Key words: injection molding, aspheric lens