Development of a bonnet polishing method

Abstract

Space optics plays a key role in advancing imaging technologies, affecting directly to the quality of the results and data obtained. The high quality of the mentioned optics is only obtained after a rigorous and very long process which includes different stages such as the surface polishing. This report investigates an under-development but highly important polishing process: bonnet polishing. By means of the Zeeko IRP1200 machine the process of bonnet polishing is being studied, trying to optimize some parameters in order to improve the method and obtain better future results. More specifically, the studied parameters are the tool feed rate, the bonnet pressure and the abrasive’s grain size. To achieve this, a design of experiment (DOE) is set up, planning several experiments in different samples to combine the different possible values for the three parameters. The characterization of results is afterwards done by measurements of surface form and surface roughness using different interferometers. Preliminary results indicate that adjusting these parameters can significantly affect the quality of the polished surfaces. All in all, the developed experiments provide new fundamental information on the bonnet polishing process, giving valuable information about the use and selection of the different parameters. These results may be applied in future optical projects, as well as leaving place for future new studies on the topic.