Method for improving focusing precision of zoom optical system

Abstract

The invention belongs to an optimal design method of a zoom optical system. In order to solve the technical problems that the focusing stroke of a focusing group is too large, the focusing is slow andthe focusing precision is insufficient due to the fact that the focusing amount is not considered at the same time in the existing method for improving the focusing precision, the invention providesa method for improving the focusing precision of a zoom optical system, which comprises the following steps of: S1, optimizing the imaging quality of the zoom optical system; s2, carrying out passivesemi-athermalization design of the zoom optical system; s3, designing a focusing cam curve of the zoom optical system; and S4, adjusting and confirming the focusing precision. Starting from the sourceof an optical system, a passive semi-athermalization design method adopted by a zoom optical system is provided, namely, short focus is in passive athermalization design, and a linear design method is adopted by a focusing cam curve. The focusing amount of the focusing group is greatly reduced, and quick focusing of a zoom system is facilitated; and the focusing precision of the system is greatlyimproved, and the defects of a traditional focusing curve are overcome.

Description

technical field [0001] The invention belongs to a zoom optical system optimization design method, in particular to a method for improving the focusing precision of a zoom optical system. Background technique [0002] The application of zoom lenses has a history of decades and is widely used in all aspects of life. The optical path structure of the zoom lens is generally composed of a front fixed group, a zoom group, a compensation group and a rear fixed group. Usually, the fixed group is selected as the focusing group. By moving the focusing group back and forth along the optical axis, the zoom system is compensated for the defocus caused by the influence of the external environment temperature and the distance change of the target, so as to ensure the imaging clarity of the entire system. Focusing accuracy is an important indicator of the zoom system. The focusing accuracy generally takes 1 / 2 to 1 / 4 of the focal depth of the optical system, which directly affects the imagi...

AI Technical Summary

Problems solved by technology

[0006] The main purpose of the present invention is to solve the technical problems that the existing method for improving the focusing precision does not take into account the focusing amount at the same time, resulting in an excessively large focusing stroke of the focusing group, resulting in slow focusing and insufficient improvement in focusing precision, and provides an improved Method of Focusing Accuracy of Zoom Optical System

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