A monitoring zoom lens and video camera with same

Abstract

The invention discloses a monitoring zoom lens and a video camera with the zoom lens. The monitoring zoom lens includes: a front fixed group lens; a rear fixed group lens; a diaphragm, which is arranged between the front fixed group lens and the rear fixed group lens; a zoom group lens, which is movably arranged on the lens and located between the front fixed lens group and the diaphragm; and a focusing group lens, which is movably arranged in the lens and located behind the diaphragm and the rear fixed group lens, wherein the monitor The maximum aperture of the zoom lens when used at the maximum focal length end is the same as its maximum aperture when used at the minimum focal length end; and the maximum aperture of the monitored zoom lens when used at the intermediate focal length segment is the same as the maximum aperture when used at the minimum focal length end same. The beneficial effect of the present invention is that the maximum aperture of the lens will not be reduced when the lens is used at any focal length; compared with other lenses, the camera used with this lens has a better low-light effect.

Description

technical field [0001] The invention relates to the technical field of video monitoring, in particular to a monitoring zoom lens and a video camera with the same. The invention relates to the field of surveillance camera lenses, in particular to a zoom lens with a constant large aperture. Background technique [0002] At present, surveillance cameras are more and more widely used, and cameras have higher and higher requirements for lens performance. Through the zoom function of the lens, the camera can realize the shooting and monitoring of different scenes near and far. When the lens is adjusted to a shorter focal length, the camera can monitor a closer scene; when the lens is adjusted to a longer focal length, the camera can monitor a farther scene. [0003] The aperture value is a parameter that identifies the light transmission ability of the lens. The larger the aperture value, the stronger the light transmission ability of the lens; the smaller the aperture value, th...

AI Technical Summary

Problems solved by technology

Due to the complex working scene of the camera, the actual focal length of the lens may not be the minimum focal length

And when this kind of ordinary lens is not used at the minimum focal length, the light transmission ability of the lens will decrease to a certain extent, and this effect will eventually be reflected in the image output by the camera: the image output by the camera becomes darker, especially when shooting some In an ultra-low-light scene, the output image is very dark, which seriously affects the overall image quality

Although some image processing methods can improve the brightness of the image to a certain extent, it will also increase the noise of the image and affect the quality of the image.

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