Study on the Heat and Pressure and Their Effect on the Surface Shape Precision of Optic in Continuous Polishing

In the process of ring polishing, the non-uniform temperature distribution in the element will make the shape of the element change greatly, which leads to the non-uniform pressure distribution between the element and the pad. According to Preston equation, uneven pressure distribution will produce uneven material removal rate and affect the surface morphology of optics. In this paper, the influence of temperature differenace on the deformation of the element is revealed, and then the relationship between the deformation and the contact pressure of the element is deduced. Combined with Preston equation, the temperature difference in the element and the surface accuracy of the element are finally connected, and verified by the surface shape measurement.