Method and device for measuring pixel pitch of image sensor based on point-target image splicing technology

Abstract

A method and a device for measuring the pixel pitch of an image sensor based on the point-target image splicing technology, which belong to the length, width or thickness metering field included in the field of metering equipment which is characterized by using an optical method. The method includes placing the point targets in different fields of view, and performing twice imaging of the point targets; constructing linear images according to the two point-target images; searching value ranges of the pixel pitch in the frequency domain, and calculating to obtain the pixel pitch by means of the search algorithm according to the best contact ratio of the actual modulation transfer function(MTF) curve related to the pixel pitch and the theoretical MTF curve related to the pixel pitch under the condition of the least square. Sliders bearing the point targets are arranged on a first guide rail and a second guide rail, and the movement of the slider on the first guide rail matches with the movement of the slider on the second guide rail so that the point targets can be focused correctly to form images on the surface of the image sensor at the position of any field of view. The method and the device for measuring the pixel pitch of the image sensor are favorable for reducing errors among results of single measurements, so that repetition of measuring results can be increased.

Description

technical field [0001] The method and device for measuring the pixel distance of an image sensor by using point target image stitching belong to the field of measuring length, width or thickness in the field of measuring equipment characterized by the use of optical methods, and especially relate to a static point target based on two frames in the frequency domain. An image sensor pixel pitch measurement method and device for an image splicing method. Background technique [0002] Image sensor pixel pitch is a very important technical indicator in the field of precision measurement. For example, if a target with a known size is imaged through an optical system, the size of the target image can be known according to the number of pixels of the image sensor occupied by the target image and the pixel pitch, and finally the size of the target image can be compared with the target size to obtain The lateral magnification of the optical system can be calibrated; in addition, when...

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Problems solved by technology

[0041] The present invention aims at the problem that the above-mentioned existing measurement method is not suitable for measurement in a small field of view, and the problem that the existing measurement device has defocus, and proposes a method and device for measuring the pixel pitch of an image sensor in the frequency domain. Improves the repeatability of measurement results within the field; the device can eliminate the influence of defocus on measurement results

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