Telecentric lens for machine vision equipment

Abstract

The invention discloses a telecentric lens for machine vision equipment. The telecentric lens comprises a lens barrel and a secondary device. The left end of the lens barrel is provided with a light adjusting shaft of which the right side is fixedly connected into the lens barrel. The left end of the light adjusting shaft is provided with a filter of which the right side is fixedly connected intothe light adjusting shaft. The left side of the filter is provided with the secondary device of which the right side is fixedly connected into the filter. When people use an imperfectly parallel lightsource to conduct image measurement on three-dimensional objects, the peripheries of the objects to be measured cause the illusion of perspective drift as the height changes, and consequently, the extra measuring errors are generated. Because a double-telecentric lens is fixedly connected into the lens barrel in a circular cone shape, when shooting is carried out, obtained image magnification does not vary with the object distance, and the telecentric lens for the machine vision equipment can adapt to the working environment on the spot well due to a larger field depth range.

Description

technical field [0001] The invention relates to the technical field of telecentric lenses, in particular to a telecentric lens equipped with machine vision equipment. Background technique [0002] The telecentric lens is mainly a lens specially designed to correct the parallax of traditional industrial lenses. It can be within a certain range of object distance, so that the magnification of the obtained image will not change with the change of object distance, which is not the same for the measured object. The situation on the object surface is a very important application. Due to its unique parallel optical path design, telecentric lenses have always been favored by machine vision applications that require high lens distortion. [0003] However, when the existing telecentric lens is shooting, it is difficult to zoom because the focal length is fixed. At the same time, because the aperture is small, it needs stronger illumination when the light is dark, and the working dist...

AI Technical Summary

Problems solved by technology

[0003] However, when the existing telecentric lens is shooting, it is difficult to zoom because the focal length is fixed. At the same time, because the aperture is small, it needs stronger lighting when the light is dark, and the working distance is relatively short, so it is impossible to perform long-distance shooting. Clear zoom shooting, and because environmental factors have a great impact on the imaging effect, it is inconvenient to use

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