METHOD AND DEVICE FOR PRODUCING AN ELEMENT HAVING AT LEAST ONE FREEFORM SURFACE WITH HIGH DIMENSIONAL ACCURACY AND LOW SURFACE ROUGHNESS

摘要

The present invention relates to a method for producing an element having at least one arbitrarily freely formed surface (freeform surface) with high dimensional accuracy and low surface roughness, and to an optical element having an optical freeform surface and a projection exposure system for microlithography having a corresponding optical element, wherein the freeform surface is obtained by means of at least one first processing step using a forming material processing method, in which at least an approximation of the desired freeform surface (target shape) occurs, and at least one second step using a surface-smoothing material processing method, wherein at least during a second processing step for smoothing material processing the element (1) to be processed is elastically stressed by applying a force such that the freeform surface to be smoothed can be processed using smoothing processes for spherical, planar or aspherical surfaces. The invention further relates to a corresponding device for smoothing an arbitrarily freely formed surface (freeform surface) of an element with high dimensional accuracy and low surface roughness having a holder for receiving the element to be processed and a smoothing tool for the smoothing processing of the freeform surface, wherein the receptacle has at least one actuator (6) for applying a force to the element to be processed, so that the element to be processed is elastically stressed into an intermediate shape (2''), so that the freeform surface to be smoothed can be processed by means of the smoothing tool using smoothing processes for spherical, planar or aspherical surfaces.