Achromatic prime lens

Abstract

The invention relates to an achromatic prime lens sequentially comprising a first lens with negative focal power, an aperture diaphragm, a second lens group with positive focal power, a third lens with positive focal power and an imaging surface with an imaging element from an object side to an image side. The second lens group comprises at least three glued lenses. According to the invention, 4Kultra-high-definition resolution is realized, the achromatic prime lens can be used with an image sensor with more than 12,000,000 pixels, so that the imaging quality is greatly improved, a larger scene picture can be shot, and the picture is still clear even if the picture is amplified; on the basis of a special lens matching mode and a surface type design, infrared confocal in the whole processfrom low temperature to high temperature is achieved by adopting a temperature drift compensation technology, clear imaging in 24 hours is ensured, and a high-contrast image can be shot even in a hazeenvironment; and a plurality of glued lenses are designed, so that the reduction degree of the picture is extremely high, and obvious bending and distortion phenomena are avoided.

Description

technical field [0001] The invention relates to a technology in the field of optical devices, in particular to an achromatic fixed-focus lens. Background technique [0002] The pictures presented by existing surveillance cameras during monitoring are not clear enough, especially for enlarged pictures of details. In general, the sharper the picture, the more difficult it is to design, and it is more difficult to express it in a high-resolution picture. With the improvement of camera pixels, high resolution and high pixels often correspond to large size and high cost, the number of lenses will increase accordingly, and the overall structure of the lens will become more complex. Therefore, at this stage, it is difficult for fixed-focus lenses for surveillance cameras to take into account many constraints that affect lens quality, such as size, cost, imaging quality, infrared confocal, and temperature drift compensation. Contents of the invention [0003] Aiming at the above...

AI Technical Summary

Problems solved by technology

With the improvement of camera pixels, high resolution and high pixels often correspond to large size and high cost, the number of lenses will increase accordingly, and the overall structure of the lens will become more complex

Therefore, at this stage, it is difficult for the fixed-focus lens used for surveillance cameras to take into account the factors that affect the quality of the lens, such as size, cost, image quality, infrared confocal, temperature drift compensation, etc.

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