Optimisation of the optical part quality of polymer glasses in the injection compression moulding process

Abstract

The substitution of glass for optical parts, e. g., lenses and window panes, by polymers is continuously gaining more importance in the industrial application. In coparison with conventional optical glass parts, polymers offer several significant advantages. Employing the injection moulding process optical parts with complex geometries and mounting features can be produced in just a single operation within a relative short cycle time. Furthermore, increasing quality requirements are forcing more and more companies to look at the advantages of special injection moulding processes. The specific process sequence of the injection compression moulding process offers the opportunity to produce mouldings with a lower required filling pressure and a lower molecular orientation. Thie paper presents an examination on the extent to which a better optical quality can be achieved in the moulding through the use of the injection compression moulding process in comparison to the conventional injection moulding process. After determining the significant parameters, that influence the optical quality of the moulded part, a concluding comparison of the measurements shows that there is a tendency for the injection compression moulding process to yield better optical qualities of the moulded part.