This book highlights the tools and processes used to produce high-quality glass molded optics using commercially available equipment. Combining scientific data with easy-to-understand explanations of specific molding issues and general industry information based on firsthand studies and experimentation, it provides useful formulas for readers involved in developing develop in-house molding capabilities, or those who supply molded glass optics. Many of the techniques described are based on insights gained from industry and research over the past 50 years, and can easily be applied by anyone familiar with glass molding or optics manufacturing. There is an abundance of information from around the globe, but knowledge comes from the application of information, and there is no knowledge without experience. This book provides readers with information, to allow them to gain knowledge and achieve success in their glass molding endeavors.

A temperature and strain rates dependent fracture model is developed based on Weibull statistics to quantitatively describe the brittle-ductile transition of glass fracture in precision glass molding process. Under the assistance of FEM simulation, this fracture model can be used to calculate the fracture probability of glass during the precision glass molding process. Meanwhile, the most probable fracture timing, location of fracture initiation and fracture pattern can be also predicted.

Precision glass molding is a net-shaping process to fabricate glass optics by replicating optical features from precision molds to glass at elevated temperature. The advantages of precision glass molding over traditional glass lens fabrication methods make it especially suitable for the production of optical components with complicated geometries, such as aspherical lenses, diffractive hybrid lenses, microlens arrays, etc. Despite of these advantages, a number of problems must be solved before this process can be used in industrial applications. The primary goal of this research is to determine the feasibility and performance of nonconventional optical components formed by precision glass molding. This research aimed to investigate glass molding by combing experiments and finite element method (FEM) based numerical simulations. The first step was to develop an integrated compensation solution for both surface deviation and refractive index drop of glass optics. An FEM simulation based on Tool-Narayanaswamy-Moynihan (TNM) model was applied to predict index drop of the molded optical glass. The predicted index value was then used to compensate for the optical design of the lens. Using commercially available general purpose software, ABAQUS, the entire process of glass molding was simulated to calculate the surface deviation from the adjusted lens geometry, which was applied to final mold shape modification. A case study on molding of an aspherical lens was conducted, demonstrating reductions in both geometry and wavefront error by more than 60%.

The study of manufacturing process of an infrared lens by using a commercial glass molding machine, GP-10000HT, is the second step to figure out all the details of a real precision glass molding process that help us to provide a simulation that makes a better prediction of glass molding process.

Molding tools in precision glass molding fail easily, even with protective thin film coatings applied. In this work, various efficient methods for assessing glass-coating interactions are developed, including a new, automated testing rig. Analysis of the testing results provides a better understanding of these mechanisms and how they are influenced by material properties and process parameters, so that the appropriate measures can be taken to prolong the life of the molding tools.