Investigation on an innovative approach for clamping contact lens mould inserts in ultraprecision machining using an adaptive precision chuck and its application perspectives

Abstract

This paper presents an innovative approach for the accuracy and precision analysis of the ultraprecision machining systems, further supported in experiment trials and data on ultraprecision machining of contact lens mould inserts. Statistical models are developed for analysing the measurement data of geometrical runout of the insert components before and after the ultraprecision machining. The maximum standard deviation of 16 nm and 5 nm residual in geometrical runout is achieved after ultraprecision machining of all 26 contact lens mould insert components. The system obtained 76% of accuracy and precision confident with positioning range of 2–40nm, according to data collected from the experimental trials. The surface finishing is very encouraging with the maximum 4 nm of Ra and 43 nm of PV as achieved from the experiments. Furthermore, it has been found that the clamping stiffness of the smart chuck has a positive effect on the accuracy of the machining system. The experimental trial results show the smart chuck can be used as a universal highly effective device, particularly for ultraprecision production purpose.