PRODUCTION OF OPTICAL PARTS WITH ADAPTED PROCESS AND MOULD TECHNOLOGY

W. Michaeli, J. Forster

 

Institut für Kunststoffverarbeitung (IKV), Pontstraße 49,

D-52062 Aachen, Germany

 

 

ABSTRACT

 

      This paper presents research in the field of injection moulding and injection-compression moulding of optical plastics parts. The injection moulding of optical components requires sophisticated machine and mould technology as well as a good know-how about the injection moulding process itself. In this work, investigations were carried out on the basis of an exemplary plano-convex lens. This exemplary lens with a diameter of 100 mm and a maximum thickness of 15 mm was produced both using the injection moulding and the injection-compression moulding process. The quality of an optical part is dependent on the accuracy of its surface geometry and on its inner properties. To analyse the influence of the main process parameters on the quality of the exemplary lens, measuring methods and quality criteria were defined. The convex surface of the lens was surveyed using an interferometer, the inner properties were visualised with polarised images. This paper points out the effect of the main process parameters on the quality of an exemplary lens. It compares the results that could be achieved using the injection moulding process with the results obtained by its variant, the injection-compression moulding process.