阅读说明：本技术 一种小倍率摄像头和小倍率变焦镜头 (Small-magnification camera and small-magnification zoom lens ) 是由 王志超 于 2020-07-13 设计创作，主要内容包括：本发明公开了一种小倍率摄像头和小倍率变焦镜头,涉及摄像技术领域。本发明包括：小倍率变焦镜头；及图像拾取元件,被配置为接收由所述小倍率变焦镜头形成的图像；所述变小倍率焦镜头从物面侧到像面侧依次包括：具有正光焦度的第一固定透镜群、具有负光焦度的第二变焦透镜群、光阑、具有负光焦度的第三固定透镜群、具有负光焦度的第四聚焦透镜群和具有正光焦度的第五固定透镜群。本发明具有4K解像力、红外共焦、畸变小且镜头总长短,能够在-40℃~85℃的极端环境下依旧具有良好的成像质量,更适应市场需求。(The invention discloses a small-magnification camera and a small-magnification zoom lens, and relates to the technical field of camera shooting. The invention comprises the following steps: a small magnification zoom lens; and an image pickup element configured to receive an image formed by the small-magnification zoom lens; the zoom lens sequentially comprises from the object plane side to the image plane side: the zoom lens comprises a first fixed lens group with positive focal power, a second zoom lens group with negative focal power, a diaphragm, a third fixed lens group with negative focal power, a fourth focusing lens group with negative focal power and a fifth fixed lens group with positive focal power. The invention has 4K resolution, infrared confocal, small distortion and short total lens length, can still have good imaging quality in an extreme environment of-40-85 ℃, and is more suitable for market demands.)

1. A small magnification camera, comprising:

a small magnification zoom lens;

and an image pickup element configured to receive an image formed by the small-magnification zoom lens;

the small-magnification focal lens sequentially comprises from the object plane side to the image plane side:

a first fixed lens group having positive optical power, a second zoom lens group having negative optical power, a diaphragm, a third fixed lens group having negative optical power, a fourth focus lens group having negative optical power, and a fifth fixed lens group having positive optical power, wherein: the second zoom lens group can be adjusted along the optical axis to realize zooming from the wide-angle end to the telephoto end, and the fourth focusing lens group can be adjusted along the optical axis to realize focusing under different magnifications;

the second zoom lens group includes: at least three lenses, wherein: the three lenses are two lenses with negative focal power and one lens with positive focal power in sequence;

the fifth fixed lens group includes: at least two lenses, wherein: the two lenses are a lens with positive focal power and a lens with negative focal power in sequence;

the first fixed lens group includes in order: a cemented lens having a positive power as a whole composed of a lens having a negative power and a lens having a positive power, wherein: the concave surface of the cemented lens faces the image side;

the third fixed lens group includes in order: two lenses having positive power, and a cemented lens having negative power as a whole composed of a lens having negative power and a lens having positive power, wherein: at least one lens is an aspheric lens, and the concave surface of the cemented lens faces the image side;

the fourth focusing lens group is a lens with negative focal power.

2. The small-magnification camera according to claim 1, wherein:

the ratio range of the focal length of the first lens of the first fixed lens group to the focal length of the wide-angle end of the lens is (-8, -4), the refractive index is greater than 1.80, and the Abbe number is less than 25;

the ratio range of the focal length of the second lens of the first fixed lens group to the focal length of the wide-angle end of the lens is (2,3), the refractive index is greater than 1.60, and the Abbe number is less than 60;

the ratio range of the focal length of the third lens of the first fixed lens group to the focal length of the wide-angle end of the lens is (4,6), the refractive index is less than 1.50, and the Abbe number is greater than 80.

3. The small-magnification camera according to claim 1, wherein:

the ratio range of the focal length of the first lens of the second zoom lens group to the focal length of the wide-angle end of the lens is (-2, -1), the refractive index is greater than 1.70, and the Abbe number is less than 30;

the ratio range of the focal length of the second lens of the second zoom lens group to the focal length of the wide-angle end of the lens is (-2, -1), the refractive index is greater than 1.60, and the Abbe number is less than 65;

the ratio range of the focal length of the third lens of the second zoom lens group to the focal length of the wide-angle end of the lens is (3, 4).

4. The small-magnification camera according to claim 1, wherein:

the first lens of the third fixed lens group is an aspheric lens, the ratio range of the focal length of the first lens to the focal length of the wide-angle end of the lens is (1,2), the refractive index is less than 1.70, and the Abbe number is greater than 50;

the ratio range of the focal length of the second lens of the third fixed lens group to the focal length of the wide-angle end of the lens is (1.5,3), the refractive index is less than 1.50, and the Abbe number is greater than 80;

the ratio range of the focal length of the third lens of the third fixed lens group to the focal length of the wide-angle end of the lens is (-1.5, -0.8), the refractive index is greater than 1.60, and the Abbe number is greater than 35;

the ratio range of the focal length of the fourth lens of the third fixed lens group to the focal length of the wide-angle end of the lens is (1,1.5), the refractive index is less than 1.50, and the Abbe number is greater than 80.

5. The small-magnification camera according to claim 1, wherein:

the ratio range of the focal length of the lens of the fourth focusing lens group to the focal length of the wide-angle end of the lens is (-2, -1), the refractive index is greater than 1.70, and the Abbe number is less than 30.

6. The small-magnification camera according to claim 1, wherein:

the ratio range of the focal length of the first lens of the fifth fixed lens group to the focal length of the wide-angle end of the lens is (0.8,1.5), the refractive index is greater than 1.90, and the Abbe number is greater than 35;

the ratio of the focal length of the second lens of the fifth fixed lens group to the focal length of the wide-angle end of the lens is (-2, -1).

7. A small-magnification zoom lens includes, in order from an object surface side to an image surface side:

a first fixed lens group having positive optical power, a second zoom lens group having negative optical power, a diaphragm, a third fixed lens group having negative optical power, a fourth focus lens group having negative optical power, and a fifth fixed lens group having positive optical power, wherein: the second zoom lens group can be adjusted along the optical axis to realize zooming from the wide-angle end to the telephoto end, and the fourth focusing lens group can be adjusted along the optical axis to realize focusing under different magnifications;

the second zoom lens group includes: at least three lenses, wherein: the three lenses are two lenses with negative focal power and one lens with positive focal power in sequence;

the fifth fixed lens group includes: at least two lenses, wherein: the two lenses are a lens with positive focal power and a lens with negative focal power in sequence;

the first fixed lens group includes in order: a cemented lens having a positive power as a whole composed of a lens having a negative power and a lens having a positive power, wherein: the concave surface of the cemented lens faces the image side;

the third fixed lens group includes in order: two lenses having positive power, and a cemented lens having negative power as a whole composed of a lens having negative power and a lens having positive power, wherein: at least one lens is an aspheric lens, and the concave surface of the cemented lens faces the image side;

the fourth focusing lens group is a lens with negative focal power.

Technical Field

The invention relates to the technical field of camera shooting, in particular to a small-magnification camera and a small-magnification zoom lens.

Background

Along with the improvement of the technical level of software in the field of camera shooting, the AI technology is continuously applied to the zoom camera lens, and the requirement of a view field on the camera lens is gradually improved. The camera lens is required to adapt to different working environment requirements, particularly the AI lens is closely related to a face recognition technology, so that the requirements on definition and reliability are more strict. In order to meet the requirement of day and night sharing, the camera lens also needs to have the confocal characteristic of visible and infrared wave bands. The general imaging quality of mass-production small-magnification zoom lenses with focal lengths within the range of 8-32 in the current market mostly meets the technical requirements of AI (artificial intelligence) at lunch, and a promotion space also exists in the aspects of relative aperture and infrared confocal.

Disclosure of Invention

The invention solves the technical problems in the prior art, and provides a small-magnification camera and a small-magnification zoom lens, which have 4K resolving power, infrared confocal property, small distortion and short total lens length, can still have good imaging quality in an extreme environment of-40-85 ℃, and are more suitable for market demands.

The technical scheme provided by the invention is as follows:

a small magnification camera, comprising: a small magnification zoom lens; and an image pickup element configured to receive an image formed by the small-magnification zoom lens; the zoom lens sequentially comprises from the object plane side to the image plane side: a first fixed lens group having positive optical power, a second zoom lens group having negative optical power, a diaphragm, a third fixed lens group having negative optical power, a fourth focus lens group having negative optical power, and a fifth fixed lens group having positive optical power, wherein: the second zoom lens group can be adjusted along the optical axis to realize zooming from the wide-angle end to the telephoto end, and the fourth focusing lens group can be adjusted along the optical axis to realize focusing under different magnifications; the second zoom lens group includes: at least three lenses, wherein: the three lenses are two lenses with negative focal power and one lens with positive focal power in sequence; the fifth fixed lens group includes: at least two lenses, wherein: the two lenses are a lens with positive focal power and a lens with negative focal power in sequence; the first fixed lens group includes in order: a cemented lens having a positive power as a whole composed of a lens having a negative power and a lens having a positive power, wherein: the concave surface of the cemented lens faces the image side; the third fixed lens group includes in order: two lenses having positive power, and a cemented lens having negative power as a whole composed of a lens having negative power and a lens having positive power, wherein: at least one lens is an aspheric lens, and the concave surface of the cemented lens faces the image side; the fourth focusing lens group is a lens with negative focal power.

Preferably, the ratio of the focal length of the first lens of the first fixed lens group to the focal length of the wide-angle end of the lens is (-8, -4), the refractive index is greater than 1.80, and the abbe number is less than 25; the ratio range of the focal length of the second lens of the first fixed lens group to the focal length of the wide-angle end of the lens is (2,3), the refractive index is greater than 1.60, and the Abbe number is less than 60; the ratio range of the focal length of the third lens of the first fixed lens group to the focal length of the wide-angle end of the lens is (4,6), the refractive index is less than 1.50, and the Abbe number is greater than 80.

Preferably, the ratio of the focal length of the first lens of the second zoom lens group to the focal length of the wide-angle end of the lens is (-2, -1), the refractive index is greater than 1.70, and the abbe number is less than 30; the ratio range of the focal length of the second lens of the second zoom lens group to the focal length of the wide-angle end of the lens is (-2, -1), the refractive index is greater than 1.60, and the Abbe number is less than 65; the ratio range of the focal length of the third lens of the second zoom lens group to the focal length of the wide-angle end of the lens is (3, 4).

Preferably, the first lens of the third fixed lens group is an aspheric lens, the ratio of the focal length of the aspheric lens to the focal length of the wide-angle end of the lens is (1,2), the refractive index is less than 1.70, and the abbe number is greater than 50; the ratio range of the focal length of the second lens of the third fixed lens group to the focal length of the wide-angle end of the lens is (1.5,3), the refractive index is less than 1.50, and the Abbe number is greater than 80; the ratio range of the focal length of the third lens of the third fixed lens group to the focal length of the wide-angle end of the lens is (-1.5, -0.8), the refractive index is greater than 1.60, and the Abbe number is greater than 35; the ratio range of the focal length of the fourth lens of the third fixed lens group to the focal length of the wide-angle end of the lens is (1,1.5), the refractive index is less than 1.50, and the Abbe number is greater than 80.

Preferably, the ratio of the focal length of the lenses of the fourth focusing lens group to the focal length of the wide-angle end of the lens is (-2, -1), the refractive index is greater than 1.70, and the abbe number is less than 30.

Preferably, the ratio of the focal length of the first lens of the fifth fixed lens group to the focal length of the wide-angle end of the lens is (0.8,1.5), the refractive index is greater than 1.90, and the abbe number is greater than 35; the ratio of the focal length of the second lens of the fifth fixed lens group to the focal length of the wide-angle end of the lens is (-2, -1).

Another object of the present invention is to provide a small magnification zoom lens, including, in order from an object plane side to an image plane side: a first fixed lens group having positive optical power, a second zoom lens group having negative optical power, a diaphragm, a third fixed lens group having negative optical power, a fourth focus lens group having negative optical power, and a fifth fixed lens group having positive optical power, wherein: the second zoom lens group can be adjusted along the optical axis to realize zooming from the wide-angle end to the telephoto end, and the fourth focusing lens group can be adjusted along the optical axis to realize focusing under different magnifications; the second zoom lens group includes: at least three lenses, wherein: the three lenses are two lenses with negative focal power and one lens with positive focal power in sequence; the fifth fixed lens group includes: at least two lenses, wherein: the two lenses are a lens with positive focal power and a lens with negative focal power in sequence; the first fixed lens group includes in order: a cemented lens having a positive power as a whole composed of a lens having a negative power and a lens having a positive power, wherein: the concave surface of the cemented lens faces the image side; the third fixed lens group includes in order: two lenses having positive power, and a cemented lens having negative power as a whole composed of a lens having negative power and a lens having positive power, wherein: at least one lens is an aspheric lens, and the concave surface of the cemented lens faces the image side; the fourth focusing lens group is a lens with negative focal power.

Compared with the prior art, the small-magnification camera and the small-magnification zoom lens provided by the invention have the following beneficial effects:

the invention adopts a five-group structure with negative group aggregation, limits the caliber size of one group of lenses to control the cost, uses an aspheric surface near the three groups of diaphragms to improve the performance, realizes short overall length, small distortion, low cost and high performance of the lens, and is suitable for the requirement of the field of shooting on a small-magnification lens.

Drawings

The above features, technical features, advantages and implementations of a small power camera and a small power zoom lens will be further described in the following detailed description of preferred embodiments with reference to the accompanying drawings.

FIG. 1 is a schematic view of the structure of example 1 in the middle;

FIG. 2 is a schematic view of the structure of the embodiment 1 at the telephoto end;

FIG. 3 is a schematic structural view at the wide-angle end in accordance with example 1;

FIG. 4 is an on-axis aberration diagram at the center in example 1;

FIG. 5 is an on-axis aberration diagram at the telephoto end in example 1;

FIG. 6 is an on-axis aberration diagram at the wide-angle end of example 1;

FIG. 7 is a graph of chromatic aberration of magnification in the middle of example 1;

FIG. 8 is a chromatic aberration of magnification at the telephoto end in example 1;

FIG. 9 is a chromatic aberration of magnification diagram at the wide-angle end of example 1;

FIG. 10 is a schematic view of the structure of the middle part of the embodiment 2;

FIG. 11 is a schematic view showing the structure of the telescope of embodiment 2;

FIG. 12 is a schematic structural view at the wide-angle end in accordance with example 2;

FIG. 13 is an on-axis aberration diagram at the center in example 2;

FIG. 14 is an on-axis aberration diagram at the telephoto end in accordance with example 2;

FIG. 15 is an on-axis aberration diagram at the wide-angle end of example 2;

FIG. 16 is a graph of chromatic aberration of magnification in the middle of example 2;

FIG. 17 is a chromatic aberration of magnification at the telephoto end in example 2;

FIG. 18 is a chromatic aberration of magnification diagram at the wide-angle end in example 2;

FIG. 19 is a schematic view of the structure of the middle part of embodiment 3;

FIG. 20 is a schematic structural view of the embodiment 3 at the telephoto end;

FIG. 21 is a schematic structural view at the wide-angle end in accordance with embodiment 3;

FIG. 22 is an on-axis aberration diagram in the middle of example 3;

FIG. 23 is an on-axis aberration diagram at the telephoto end in example 3;

FIG. 24 is an on-axis aberration diagram at the wide-angle end of example 3;

FIG. 25 is a graph of chromatic aberration of magnification in the middle of example 3;

FIG. 26 is a chromatic aberration of magnification at the telephoto end in example 3;

FIG. 27 is a chromatic aberration of magnification diagram at the wide-angle end of example 3;

the reference numbers illustrate: a first fixed lens group G1, a second zoom lens group G2, a third fixed lens group G3, a fourth focus lens group G4, a fifth fixed lens group G5, an image plane IMG, a stop STP, a protective glass CG, first to fifteenth lenses L1 to L15.

Detailed Description

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following description will be made with reference to the accompanying drawings. It is obvious that the drawings in the following description are only some examples of the invention, and that for a person skilled in the art, other drawings and embodiments can be derived from them without inventive effort.

For the sake of simplicity, only the parts relevant to the invention are schematically shown in the drawings, and they do not represent the actual structure as a product. In addition, in order to make the drawings concise and understandable, components having the same structure or function in some of the drawings are only schematically illustrated or only labeled. In this document, "one" means not only "only one" but also a case of "more than one".