High-resolution, large-image-plane, small-size and infrared confocal zoom optical system

Abstract

The invention relates to the technical field of an optical lens, in particular to a high-resolution, large-image-plane, small-size and infrared confocal zoom optical system, which is sequentially provided with, from an object side to an image side, a first lens group with a positive focal length, a second lens group with a negative focal length, a diaphragm, a third lens group with a positive focal length, a fourth lens group with a positive focal length and a photosensitive chip. The first lens group, the diaphragm and the third lens group are fixed with respect to the photosensitive chip, the second lens group and the fourth lens group can move forward and backward with respect to the photosensitive chip, the second lens group moves toward the third lens group gradually when the opticalsystem changes from a short focal length to a long focal length, and a focusing effect is realized when the fourth lens group moves with respect to the photosensitive chip. The third lens group includes three lenses, wherein one aspheric lens in the third lens group and one aspheric lens arranged in the second lens group can perform aberration correction. An aspheric lens in the fourth lens groupcan perform correction of the field curvature.

Description

technical field [0001] The invention relates to the technical field of optical lenses, in particular to a zoom optical system with high resolution, large image plane, small volume and infrared confocal. Background technique [0002] At present, zoom lenses are widely used in people's daily life. The current market is developing in the direction of high resolution and high image quality. In order to obtain better imaging quality, using chips with larger pixels and more pixels is the solution to the problem. One of the fundamental ways, but the current security monitoring and road condition monitoring devices have the following shortcomings: [0003] Ordinary zoom lenses are often not compatible with large image area and volume. The increase of image area will cause a sharp change in lens volume. Currently, large-screen surveillance lenses on the market, such as lenses with a size of about 1″, have an image area of ​​16.0 mm, its volume is relatively large, and most of them a...

AI Technical Summary

Problems solved by technology

[0003] Ordinary zoom lenses are often not compatible with large image area and volume. The increase of image area will cause a sharp change in lens volume. Currently, large-screen surveillance lenses on the market, such as lenses with a size of about 1″, have an image area of ​​16.0 mm, its volume is relatively large, and most of them are fixed-focus lenses, which are difficult to control when the monitoring distance changes;

[0004] At present, the mainstream high-quality surveillance cameras on the market have a low resolution, mostly 1080p, with 2 million pixels. However, with the improvement of data transmission speed, higher-quality image transmission becomes possible. It cannot meet the demand; the current mainstream 1080P lens image plane is mainly 1 / 2.8″, using a 1 / 2.8″ CMOS chip with an effective imaging plane diagonal of 6.2mm, its pixel size is only 2.8μm, and the resolution Not very high; and because the pixels are small, its photosensitivity and color reproduction are not very ideal, and performance improvement is urgently needed;

[0005] Most of the surveillance lenses currently on the market are non-infrared confocal lenses. Therefore, in occasions with many optical wavelength bands, such as in the evening, or when there is some lighting at night, the captured picture cannot be clear as a whole, and there will always be some blurring;

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