Automatic pose adjustment method and device for spherical optical element with large curvature radius

Abstract

The invention discloses an automatic pose adjustment method and device for a spherical optical element with a large curvature radius. According to the automatic posture adjustment method and device, ahigh-power microscope is utilized to collect a plurality of continuous dark-field gray-scale images focused to defocused correspondingly along four edge characteristic points with vertical and horizontal orthogonal diameters on the surface of the spherical optical element with the large curvature radius, an image Tenengrad operator value is calculated, the Tenengrad operator value and a high-power microscope axial movement curve are fitted, a positive focus position is searched according to an image Tenengrad operator extreme value criterion, and the spatial coordinates of each characteristicpoint are obtained; and by establishing a spatial mathematical model of the feature points and an adjusting device, the spatial coordinates of the four feature points are converted into pitch and spin two-dimensional adjustment amount to perform pose adjustment operations. The automatic posture adjustment method and device solve the defocusing problem caused by the non-parallel optical axis of the optical element and the optical axis of the microscope and the change of the rise height of the spherical optical element beyond the depth of field range of the microscope in the microscope full-aperture scanning detection process of the spherical optical element with large curvature radius.

Description

technical field [0001] The invention relates to a high-precision automatic pose adjustment method for a spherical optical element with a large curvature radius, and a pose adjustment device corresponding to the method. Background technique [0002] In inertial confinement fusion (ICF) systems, large curvature radius (R>4m) spherical optical elements are widely used. For example, the size of commonly used mirrors reaches 430mm in diameter. When detecting micron-scale defects on the surface, it is necessary to perform full-aperture scanning acquisition of dark-field microscopic scattering imaging, and then use a high-power microscope to accurately locate and extract defect features. Since the depth of field of the high-power microscope used is usually only 10 to 20 microns, if the optical axis of the spherical optical element to be tested is not parallel to the optical axis of the microscope, the positioning will be inaccurate during the high-power positioning and extractio...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to solve the detection process of large curvature radius (greater than 4m) spherical optical element surface defect, because the large curvature radius spherical optical element tilts and causes the partial sub-aperture that collects to exceed the range of depth of field of the microscope, causes the image plane to be out of focus. Focus, to provide a large curvature radius spherical optical element automatic pose adjustment method and device, so that the optical axis of the microscope is aligned with the spherical element to be tested; , in the process of scanning and collecting sub-aperture images, some sub-aperture images will still be defocused, and a "back" scanning and microscope constant working distance control method is provided, so that the spherical element with a large radius of curvature can always be maintained during scanning and collection. Avoid defocusing throughout the depth of field of the microscope, resulting in consistently sharp sub-aperture images

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