Method and apparatus for calibrating off-axis amount of off-axis parabolic mirror based on grating ruler and theodolite

Abstract

The invention discloses a method and apparatus for calibrating an off-axis amount of an off-axis parabolic mirror based on a grating ruler and a theodolite. The method comprises: a step of approximately alignment and modulation of a light path, a step of determining a focus position of an interferometer, a step of measuring an edge lint position of a feature point of a surface of an off-axis parabolic mirror, a step of measuring a distance between a crossed point of a cross curve of a second plane reflection mirror and the edge lint position of the feature point of the surface of the off-axis parabolic mirror, and a step of calculating an off-axis amount of the off-axis parabolic mirror. The feature position of the off-axis parabolic mirror is found out by using a second plant reflection mirror with the crossed curve. On the basis of cooperation of a grating ruler and a theodolite, the distance between the two feature points is measured precisely and the distance between the cross curve and the second plane mirror edge is measured; and then calculation is carried out to obtain the value of the off-axis amount of the off-axis parabolic mirror in detection. If the deviation between the value of the off-axis amount and the theoretical off-axis amount does not meet the standard, the position of the off-axis parabolic mirror is adjusted until the position is correct. The method has advantages of high calibration precision and simple calibration steps.

Description

technical field [0001] The invention relates to the field of calibration methods for the geometric quantities of off-axis curved mirrors, in particular to a method and a device for calibrating the off-axis quantities of off-axis parabolic mirrors based on grating rulers and theodolites. Background technique [0002] With the development of science and technology, off-axis curved mirrors, especially off-axis parabolic mirrors (referred to as off-axis parabolic mirrors) are increasingly used in large-aperture optical systems, such as space telescopes. In the prior art, the aberration-free point detection method is often used for off-axis paraboloids. In the detection, it is necessary to accurately calibrate the off-axis amount of the off-axis parabola mirror, so as to eliminate the extra aberration introduced by the off-axis amount deviation to the interference detection. [0003] At present, the laboratory uses a steel ruler to measure the distance between the optical axis an...

AI Technical Summary

Problems solved by technology

[0004] The present invention overcomes the shortcoming of the low precision of the existing method for calibrating the off-axis amount of the off-axis parabolic mirror, and provides a method for calibrating the off-axis amount of the off-axis parabolic mirror based on the grating ruler and theodolite, comprising the following steps,

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