Near-infrared zoom lens with embedded liquid lens assembly

Abstract

The invention discloses a near-infrared zoom lens with an embedded liquid lens assembly. The lens includes a lens barrel, lens bodies, a diaphragm, the liquid lens assembly and an optical filter; thelens bodies comprise the first lens body, the second lens body, the third lens body and the fourth lens body, wherein the first lens body, the second lens body, the third lens body, the diaphragm, theliquid lens assembly, the fourth lens and the optical filter are arrayed sequentially from an object side to an image side in the lens barrel; a double-convex glass spherical-surface lens body with positive focal power is adopted as the first lens body, a falcate glass spherical-surface lens with positive focal power is adopted as the second lens body, a double-concave glass spherical-surface lens with negative focal power is adopted as the third lens body, and a double-convex glass spherical-surface lens body with positive optical power is adopted as the fourth lens body. According to the lens, the four glass spherical-surface lens bodies and the liquid lens assembly are added, so that the problems are solved that the working distance range of traditional fixed-focus lenses is narrow, the number of existing zoom lenses in which liquid lens assemblies are embedded is large, and the definition is low.

Description

technical field [0001] The invention relates to the field of near-infrared lenses, in particular to a near-infrared zoom lens with a built-in liquid lens assembly. Background technique [0002] The depth of object space that can obtain a clear image on the image plane (usually an image sensor) is called depth of field. The depth of field is related to the diameter of the entrance pupil of the lens, the focal length and the distance to the alignment plane. The smaller the diameter of the entrance pupil, the smaller the focal length, the greater the distance to the plane, and the greater the depth of field. The traditional fixed-focus lens, especially the lens with limited object distance imaging, has a relatively short depth of field. If it is applied to recognition equipment, such as iris recognition, it can only be fixed at a certain position to produce a clear image, which is not only time-consuming, but also very inconvenient to use. [0003] In order to increase the d...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to provide a near-infrared zoom lens with a built-in liquid lens assembly, which solves the problems of narrow working distance range of trad...

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