Numerical Evaluation on the Curve Deviation of the Molded Glass Lens

作者：Zhou Jian; Li Mujun; Hu Yang; Shi Tianyi; Ji Yueliang; Shen Lianguan^*

来源：Journal of Manufacturing Science and Engineering, 2014, 136(5): 051004.

DOI：10.1115/1.4027342

• FEM simulation
• molded glass lens
• stress/structural relaxation
• curve deviation
• near contact heat transfer

The compression molding of precision glass lens is a near net-shape forming process for optical components fabrication. The final profile curve accuracy is one of the most crucial criterions for evaluating the quality of the molded lens. In this research, our purpose was focused on the evaluation of the molded lens curve deviation. By incorporating stress relaxation and structural relaxation model of glass, numerical simulations of the whole molding process for fabricating a planoconvex lens were conducted by utilizing the commercial software MSC MARC. The relationship of the three variables, i.e., the lens curve deviation, the mold curve deviation, the gap between the lens and the lower mold, was discussed and the evolution plots with time of the three variables were obtained. Details of the thermal boundary conditions were discussed by considering the contact heat transfer behavior. Then the essentiality of a small gap between the molds and the molded lens after releasing the upper mold was demonstrated. In details, the sensitivity analysis of the processing parameters was conducted, such as the releasing temperature, the cooling rate in the annealing and fast cooling stage, respectively, and the magnitude of the hold-up force. The results showed that the glass lens curve deviation was not sensitive to the choices of the releasing temperature and the cooling rate. What's more, the results indicated that the curve deviation decreased with the hold-up force increasing. Finally, with all the details considered, the final simulation results were presented accurately with good reason.

• 出版日期2014-10
• 单位中国科学技术大学