Zoom lens

Abstract

The embodiment of the invention discloses a zoom lens. The lens comprises a negative focal power compensation lens group and a positive focal power zooming lens group which are arranged from an object space to an image space along an optical axis, wherein the compensation lens group and the zooming lens group reciprocate along the optical axis during zooming; the compensation lens group comprises a first lens with negative focal power, a second lens with negative focal power and a third lens with positive focal power which are sequentially arranged from an object space to an image space; the zooming lens group comprises a fourth lens with positive focal power, a fifth lens with positive focal power, a sixth lens with negative focal power and a seventh lens with positive focal power which are sequentially arranged from an object side to an image side. The zoom lens provided by the embodiment of the invention has the focal length zoom ratio of more than or equal to 2.7, does not lose focus when used in the environment of-40 DEG C to 80 DEG C, has the wide range of change of a field angle, can achieve the confocal of visible light and infrared light, has imaging definition and resolution of more than 4 million, and has the maximum aperture of F1.6.

Description

technical field [0001] Embodiments of the present invention relate to optical lens technologies, and in particular to a zoom lens. Background technique [0002] Due to the fixed field of view of the fixed-focus lens, the fixed-focus lens cannot meet the use requirements in many scenarios. Because the field of view and focal length are continuously variable within a certain range, the zoom lens can adapt to a variety of application scenarios, so it has received great attention and application in the security field. [0003] Wide-angle zoom lenses are commonly used in security monitoring systems. At present, the mainstream wide-angle zoom lenses usually use more than 5 glass lenses, and the cost is high and it is difficult to promote them in large quantities. Contents of the invention [0004] The embodiment of the present invention provides a zoom lens to realize the design of a low-cost large aperture ultra-wide-angle high-definition zoom lens. Its focal length zoom ratio...

AI Technical Summary

Problems solved by technology

[0003] Wide-angle zoom lens is a commonly used lens type in security monitoring systems. At present, the mainstream wide-angle zoom lens usually uses more than 5 glass lenses, which is expensive and difficult to promote in large quantities.

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