Heat and force coupling analysis during precision glass molding of free-form optical elements

Abstract

As an effective method for mass production of glass lenses, precision glass molding (PGM) technology has been mature in aspherical lens technology. However, glass molding of complex surfaces such as free-form optical elements is still in its infancy. For mass-produced glass lenses, the energy consumption is mainly concentrated on the heating stage, and the cost is also a key concern. In this paper, an XY polynomial free-form optical element is simulated by the finite element method. In view of the long heating and molding time, finite element models were established, respectively, at the optimum molding temperature and a temperature point before the optimum temperature. The stress distribution and variation trend of the two methods were analyzed, and the single cycle time of the two methods was compared. The results showed that, under the premise of the maximum stress increase of 3.91 MPa, this method reduces the heating and molding time from 1000 to 910 s, which has significant advantages in terms of time and cost.