Nanometer-precision optical curved-face ion beam processing method based on non-linear modeling

Abstract

The invention discloses a nanometer-precision optical curved-face ion beam processing method based on non-linear modeling. The method includes the steps that a basic removal function of an optical curved-face part to be processed is obtained; on the basis of the basic removal function, nonlinear modeling is conducted according to the process conditions including projection distortion, processing parameters and the optical curved-face part to be processed to establish a nonlinear model of a dynamic removal function of the optical curved-face part to be processed; the dwelling time required by ion beam polishing is solved precisely according to the nonlinear model of the dynamic removal function; and ion beam polishing is performed according to the dwelling time obtained through the solution. By means of the nanometer-precision optical curved-face ion beam processing method, the influence caused by the process conditions on the material removal model can be eliminated, the solution precision of the dwelling time required by machining is improved, and precise removal of the surface shape error is achieved.

Description

technical field [0001] The invention relates to an optical element processing technology, in particular to a nano-precision optical curved surface ion beam processing method based on nonlinear modeling. Background technique [0002] With the continuous improvement of equipment performance requirements, modern optical systems have increasingly stringent requirements for the manufacturing accuracy of optical parts, such as space x-ray optical elements and extreme ultraviolet lithography objectives, which usually require surface shape accuracy to reach nanometer or even sub-nanometer precision , which poses a great challenge to optical manufacturing technology. Traditional optical processing methods can no longer meet the needs in terms of processing accuracy and processing efficiency, so it is necessary to develop new deterministic optical processing technologies. [0003] Ion beam polishing technology uses the ion sputtering effect to remove materials, and has nanometer / subn...

AI Technical Summary

Problems solved by technology

However, curved optical parts such as spherical and aspheric surfaces account for the majority of modern high-performance optical systems. For spherical and aspheric optical mirrors, the surface shape error E'(x,y,z) conversion in the three-dimensional coordinate system In the process of error representation E(x,y) in two-dimensional convolution, projection deformation will occur, and the removal function is no longer consistent at each dwell point on the projection surface. At this time, the existing material removal model no longer universal

If the removal function is still considered constant when solving the dwell time, it will inevitably affect the accurate solution of the dwell time, resulting in a reduction in processing efficiency and precision

[0005] However, the material removal models applied to the existing three-axis and five-axis machining processes of curved optical parts usually adopt approximate or compensatory machining methods, which fail to establish an accurate modification model for deterministic polishing, which affects the manufacturing accuracy and manufacturing accuracy. further improvement

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