CN214225569U

CN214225569U - Zoom lens

Info

Publication number: CN214225569U
Application number: CN202022459020.9U
Authority: CN
Inventors: 白兴安; 杨唯一; 邹文镔; 徐奉刚
Original assignee: Sunny Optics Zhongshan Co Ltd
Current assignee: Sunny Optics Zhongshan Co Ltd
Priority date: 2020-10-29
Filing date: 2020-10-29
Publication date: 2021-09-17
Anticipated expiration: 2030-10-29

Abstract

The utility model relates to a zoom lens, along thing side to image side direction, include in proper order first fixed lens group (G1) that have positive focal power, first zoom lens group (G2) that have negative focal power, diaphragm (STO), second fixed lens group (G3) that have positive focal power and focus lens group (G4) that have positive focal power. The zoom lens of the utility model has the characteristics of small volume, large aperture, high resolution, low distortion, large image surface and no virtual focus within the temperature range of-40-80 ℃.

Description

Zoom lens

Technical Field

The utility model relates to an optical system and device design technical field especially relate to a zoom.

Background

With the development of the security field, higher requirements are put forward on the imaging quality of the optical lens, such as the aspects of the lens such as resolution, zoom range, day and night confocal, high and low temperature confocal, and the like. The monitoring lens on the current market generally cannot achieve the compatibility of a large image plane and a large volume, and most of the monitoring lenses on the current market are fixed-focus lenses, so that the monitoring distance is difficult to control when changed, and meanwhile, the size is large.

In addition, the optical distortion of the monitoring lens on the market at different focal lengths changes greatly, which is not favorable for the application in the current gradually popularized artificial intelligence fields such as face recognition, license plate recognition and the like. Meanwhile, the conventional monitoring lens is usually a non-infrared confocal lens, and the definition of a shot picture is poor under the condition of insufficient light at night or evening.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to solve above-mentioned problem, provide a zoom of big light ring, big image plane, little volume.

In order to achieve the above object of the present invention, the present invention provides a zoom lens, which comprises, in order from an object side to an image side, a first fixed lens group having positive refractive power, a first zoom lens group having negative refractive power, a diaphragm, a second fixed lens group having positive refractive power, and a focusing lens group having positive refractive power.

According to an aspect of the present invention, the first fixed lens group includes, in order in an object-side to image-side direction, a first lens having negative refractive power, a second lens having positive refractive power, and a third lens having positive refractive power.

According to an aspect of the present invention, the first lens and the third lens are concave-convex lenses in a direction from the object side to the image side.

According to an aspect of the present invention, the first zoom lens group includes, in order from the object side to the image side, a fourth lens, a fifth lens having negative power, a sixth lens having positive power, and a seventh lens.

According to an aspect of the present invention, the second fixed lens group includes, in order from the object side to the image side, an eighth lens having positive power, a ninth lens having positive power, a tenth lens having positive power, and an eleventh lens having negative power.

According to an aspect of the present invention, the eighth lens is an aspherical lens.

According to an aspect of the present invention, the ninth lens is a biconvex lens.

According to an aspect of the present invention, the focusing lens group includes, in order in an object side to image side direction, a twelfth lens having positive power, a thirteenth lens having negative power, a fourteenth lens having negative power, and a fifteenth lens having positive power.

According to an aspect of the present invention, the refractive indices of the ninth lens, the tenth lens, and the eleventh lens are Nd9, Nd10, and Nd11, respectively, and satisfy: nd9 is more than or equal to 1.45 and less than or equal to 1.65, Nd10 is more than Nd9, and Nd11 is more than Nd 9;

the abbe numbers of the ninth lens, the tenth lens and the eleventh lens are Vd9, Vd10 and Vd11 respectively, and satisfy that: 62 < Vd9 < 65,30 < | Vd10-Vd11| < 60.

According to an aspect of the present invention, at least one cemented lens group is included in each of the first fixed lens group, the first zoom lens group, the second fixed lens group, and the focus lens group.

According to an aspect of the present invention, the focal lengths of the first fixed lens group, the first zoom lens group, the second fixed lens group, and the focus lens group are f1, f2, f3, and f4, the zoom lens wide-angle end focal length is fw, satisfying the relation: f1/fw is more than or equal to 1.5 and less than or equal to 9, f2/fw is more than or equal to-5 and less than or equal to-0.5, f3/fw is more than or equal to 1 and less than or equal to 4.5, and f4/fw is more than or equal to 1.2 and less than or equal to 7.5.

According to the utility model discloses an aspect, the position of diaphragm satisfies: Ls/TTL is more than or equal to 0.35 and less than or equal to 0.46, wherein Ls represents the distance between the diaphragm and the image surface, and TTL represents the total length of the zoom lens optical system.

According to the utility modelIn one aspect, the largest lens diameter in the first fixed lens group is

The total length of an optical system of the zoom lens is TTL, and the requirements are as follows:

according to an aspect of the present invention, the distance that the first zoom lens group moves from the wide-angle end to the telephoto end is D, the total optical system length of the zoom lens is TTL, and the relational expression is satisfied: D/TTL is more than or equal to 0.2 and less than or equal to 0.3.

The utility model discloses a zoom sets up according to the injecing above, has used 15 pieces of lenses, has obtained the performance of big image plane, high resolution under the condition of less lens quantity to the volume is less, can guarantee simultaneously not virtual burnt at-40 ℃ -80 ℃ temperature range. Furthermore, the utility model discloses a zoom lens can realize f-number FNO and be less than or equal to 1.8, 4X's zoom scope, not only can be dual-purpose day and night, has overcome the contradiction between big relative aperture, day and night confocal, high low temperature virtual focus and the resolving power moreover, has increased the use occasion and the environmental condition scope of camera lens, promotes the quality and the competitiveness of camera lens product.

Drawings

Fig. 1 schematically shows a schematic configuration diagram of a zoom lens according to embodiment 1 of the present invention;

fig. 2 schematically shows a wide-angle end MTF chart of the zoom lens according to embodiment 1 of the present invention at normal temperature of 20 ℃ under visible light;

fig. 3 schematically shows a defocus graph at the wide-angle end at a low temperature of-40 ℃ under visible light in the zoom lens according to embodiment 1 of the present invention;

fig. 4 schematically shows a defocus graph at the wide-angle end at a high temperature of 80 ℃ under visible light in the zoom lens according to embodiment 1 of the present invention;

fig. 5 schematically shows a schematic structural view of a zoom lens according to embodiment 2 of the present invention;

fig. 6 schematically shows a wide-angle end MTF chart of the zoom lens according to embodiment 2 of the present invention at normal temperature of 20 ℃ under visible light;

fig. 7 schematically shows a defocus graph at the wide-angle end at a low temperature of-40 ℃ under visible light in the zoom lens according to embodiment 2 of the present invention;

fig. 8 schematically shows a defocus graph at the wide-angle end at a high temperature of 80 ℃ under visible light in the zoom lens according to embodiment 2 of the present invention;

fig. 9 schematically illustrates a configuration diagram of a zoom lens according to embodiment 3 of the present invention;

fig. 10 schematically shows a wide-angle end MTF chart of the zoom lens according to embodiment 3 of the present invention at normal temperature of 20 ℃ under visible light;

fig. 11 schematically shows a defocus graph at the wide-angle end at a low temperature of-40 ℃ under visible light in the zoom lens according to embodiment 3 of the present invention;

fig. 12 schematically shows a defocus graph at the wide-angle end at a high temperature of 80 ℃ under visible light in the zoom lens according to embodiment 3 of the present invention.

Detailed Description

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

The present invention will be described in detail with reference to the accompanying drawings and specific embodiments, which are not repeated herein, but the present invention is not limited to the following embodiments.

Referring to fig. 1, the present invention provides a zoom lens, sequentially including a first fixed lens group G1, a first zoom lens group G2, a stop STO, a second fixed lens group G3, and a focusing lens group G4 along an object-to-image direction. In the present invention, the first fixed lens group G1 has positive focal power, the first zoom lens group G2 has negative focal power, and the second fixed lens group G3 has positive focal power, and the focus lens group G4 has positive focal power.

The utility model discloses a zoom lens, first zoom lens group G2 can follow the optical axis and remove, is used for realizing the utility model discloses zoom lens is from wide angle to the change of telephoto. The utility model discloses a focusing lens group G4 can remove along the optical axis for the change of compensation optics zooming in-process image plane position.

The utility model discloses a zoom lens is injectd according to the aforesaid and is arranged the utility model discloses an each component, the focal power collocation of each component of reasonable configuration makes the utility model discloses an under the less condition of zoom lens volume, realize high resolution, low distortion, big image planes, not virtual burnt in-40 ℃ -80 ℃ temperature range, possess invariable big light ring simultaneously, cooperate big image planes can promote picture luminance and image quality to have certain zoom ability, thereby make the zoom lens can adapt to the control and have the service environment who changes.

Specifically, in the zoom lens of the present invention, the first fixed lens group G1 includes, in order from the object side to the image side, a first lens L1 having negative optical power, a second lens L2 having positive optical power, and a third lens L3 having positive optical power. The first lens L1 and the third lens L3 are both concave-convex lenses.

The zoom lens of the present invention, the first zoom lens group G2 includes, in order from the object side to the image side, a fourth lens L4, a fifth lens L5 having negative refractive power, a sixth lens L6 having positive refractive power, and a seventh lens L7. The utility model discloses a zoom lens, fourth lens L4 and seventh lens L7's focal power can be for being positive or for being negative. The second fixed lens group G3 includes, in order from the object side to the image side, an eighth lens L8 having positive power, a ninth lens L9 having positive power, a tenth lens L10 having positive power, and an eleventh lens L11 having negative power. The focusing lens group G4 includes, in order in the object-to-image direction, a twelfth lens L12 having positive power, a thirteenth lens L13 having negative power, a fourteenth lens L14 having negative power, and a fifteenth lens L15 having positive power.

In the zoom lens of the present invention, the eighth lens L8 is an aspherical lens. Of course, according to the utility model discloses a conceive, the utility model discloses other lenses in the zoom can set up to glass spherical lens, also can set up to aspherical lens, so through aspherical lens's use, can reduction in production cost on the one hand. On the other hand, through the mutual collocation use of aspheric lens and glass spherical lens, be favorable to guaranteeing the utility model discloses a lens do not virtually burnt at 40 ℃ -80 ℃ temperature range.

In the present invention, the ninth lens L9 is a biconvex lens. The refractive indices of the ninth lens L9, the tenth lens L10, and the eleventh lens L11 are Nd9, Nd10, and Nd11, respectively, and satisfy: nd9 is more than or equal to 1.45 and less than or equal to 1.65, Nd10 is more than Nd9, and Nd11 is more than Nd 9. Abbe numbers of the ninth lens L9, the tenth lens L10 and the eleventh lens L11 are Vd9, Vd10 and Vd11, respectively, and satisfy: 62 < Vd9 < 65,30 < | Vd10-Vd11| < 60. So set up, can effectively correct optical system colour difference, guarantee that the face change colour of shooing restores higher.

The utility model discloses a zoom lens all contains at least one cemented lens group in first fixed lens group G1, the first group of zoom lenses G2, the fixed lens group of second G3 and the focusing lens group G4. The focal lengths of the first fixed lens group G1, the first zoom lens group G2, the second fixed lens group G3 and the focusing lens group G4 are f1, f2, f3 and f4, the zoom lens has a wide-angle end focal length fw, and the following relation is satisfied: f1/fw is more than or equal to 1.5 and less than or equal to 9, f2/fw is more than or equal to-5 and less than or equal to-0.5, f3/fw is more than or equal to 1 and less than or equal to 4.5, and f4/fw is more than or equal to 1.2 and less than or equal to 7.5.

The utility model discloses in, the position of diaphragm STO satisfies: Ls/TTL is more than or equal to 0.35 and less than or equal to 0.46, wherein Ls represents the distance between the diaphragm and the image surface, and TTL represents the total length of the zoom lens optical system. The utility model discloses a biggest lens diameter among first fixed lens group G1 does

the utility model discloses in, the distance that first zoom lens group G2 removed from wide-angle end to telephoto end is D, satisfies the relational expression: D/TTL is more than or equal to 0.2 and less than or equal to 0.3.

To sum up, the utility model discloses a zoom sets up according to the above injecing, has used 15 pieces of lenses, has obtained the performance of big image plane, high resolution under the condition of less lens quantity to the volume is less, can guarantee not virtual burnt at-40 ℃ -80 ℃ temperature range simultaneously. Furthermore, the utility model discloses a zoom lens can realize f-number FNO and be less than or equal to 1.8, 4X's zoom scope, not only can be dual-purpose day and night, has overcome the contradiction between big relative aperture, day and night confocal, high low temperature virtual focus and the resolving power moreover, has increased the use occasion and the environmental condition scope of camera lens, promotes the quality and the competitiveness of camera lens product.

The zoom lens according to the present invention will be described in detail below with 3 specific embodiments according to the above-described configuration of the present invention.

Three sets of embodiment data are as in table 1 below:

TABLE 1

The first implementation mode comprises the following steps:

fig. 1 is a schematic view showing a zoom lens structure according to a first embodiment of the present invention.

Table 2 below lists relevant parameters of each lens of the present embodiment, including surface type, radius of curvature, thickness, refractive index of material, abbe number:

TABLE 2

In the present embodiment, the first lens L1 and the second lens L2 constitute a cemented lens group, the 5 th lens L5 and the sixth lens L6 constitute a cemented lens group, the tenth lens L10 and the eleventh lens L11 constitute a cemented lens group, and the twelfth lens L12 and the thirteenth lens L13 constitute a cemented lens group. The seventh lens L7, the eighth lens L8, and the fourteenth lens L14 are aspherical lenses, and the remaining lenses are glass spherical lenses. And all aspheres satisfy:

in the formula, z is the axial distance from the curved surface to the vertex at the position which is along the direction of the optical axis and is vertical to the optical axis by the height h; c represents the curvature at the apex of the aspherical surface; k is a conic coefficient; a4, a6, A8, a10 and a12 respectively represent aspheric coefficients of fourth, sixth, eighth, tenth and twelfth orders.

Table 3 shows the aspherical surface coefficients of the aspherical lenses in the present embodiment, K is a conic constant of the surface, and A, B, C, D, E are aspherical surface coefficients of fourth order, sixth order, eighth order, tenth order, and twelfth order, respectively.

Number of noodles

K

A

B

C

D

E

S11

12.752

0.00E+00

8.21E-4

-9.15E-6

4.56E-8

-2.54E-12

S12

3.245

0.00E+00

-4.95E-6

1.21E-7

-4.68E-9

1.75E-13

S13

-14.545

0.00E+00

-5.67E-5

-1.118E-7

1.25E-8

-1.51E-10

S14

-5.245

0.00E+00

2.65E-6

-7.206E-7

1.12E-8

-9.623E-10

S23

5.753

0.00E+00

-1.58E-6

-1.18E-7

1.74E-8

-1.521E-12

S24

-1.564

0.00E+00

2.25E-5

-7.15E-7

1.65E-9

-9.63E-11

TABLE 3

Table 4 lists the wide-angle end, telephoto end magnification variation data as follows:

thickness of	Wide angle end	Telescope end
			D1	0.609	17.109
D2	17.845	1.345
			D3	3.112	4.312
D4	2.978	1.778

TABLE 4

Where D1 denotes a distance from the image side of the first solid lens group G1 to the object side of the first zoom lens group G2, D2 denotes a distance from the image side of the first zoom lens group G2 to the object side of the stop, D3 denotes a distance from the image side of the second fixed lens group G3 to the object side of the focusing lens group G4, and D4 denotes a distance from the image side of the focusing lens group G4 to the object side of the protective glass CG. Wherein "D1", "D2", "D3" and "D4" differ depending on the wide-angle end and the telephoto end.

Fig. 2 to 4 are graphs schematically illustrating an MTF graph at the wide-angle end at normal temperature of 20 ℃ under visible light, a defocus graph at the wide-angle end at low temperature of-40 ℃ under visible light, and a defocus graph at the wide-angle end at high temperature of 80 ℃ under visible light, respectively, in the zoom lens according to embodiment 1. It can be known from the attached drawings that the zoom lens obtained according to embodiment 1 of the present invention has the characteristics of large aperture, high resolution, low distortion, large image plane, and no virtual focus within the temperature range of-40 ℃ to 80 ℃ under the condition of small volume.

The second embodiment:

fig. 5 is a schematic view showing a zoom lens structure according to a second embodiment of the present invention.

Table 5 below lists relevant parameters of each lens of the present embodiment, including surface type, radius of curvature, thickness, refractive index of material, abbe number:

TABLE 5

In the present embodiment, the first lens L1 and the second lens L2 constitute a cemented lens group, the 5 th lens L5 and the sixth lens L6 constitute a cemented lens group, the tenth lens L10 and the eleventh lens L11 constitute a cemented lens group, and the twelfth lens L12 and the thirteenth lens L13 constitute a cemented lens group. The seventh lens L7, the eighth lens L8, and the fourteenth lens L14 are aspherical lenses, and the remaining lenses are glass spherical lenses.

Table 6 shows the aspherical surface coefficients of the aspherical lenses in the present embodiment, K is a conic constant of the surface, and A, B, C, D, E are aspherical surface coefficients of fourth order, sixth order, eighth order, tenth order, and twelfth order, respectively.

TABLE 6

Table 7 lists the wide-angle end, telephoto end magnification variation data as follows:

thickness of	Wide angle end	Telescope end
			D1	0.839	16.015
D2	16.358	1.182
			D3	3.212	4.019
D4	2.878	2.071

TABLE 7

Fig. 6 to 8 are graphs schematically illustrating an MTF graph at the wide-angle end at 20 ℃ at normal temperature and under visible light, a defocus graph at the wide-angle end at-40 ℃ at low temperature and under visible light, and a defocus graph at the wide-angle end at 80 ℃ at high temperature and under visible light, respectively, in the zoom lens of embodiment 2. It can be known from the attached drawings that the zoom lens obtained according to embodiment 2 of the present invention has the characteristics of large aperture, high resolution, low distortion, large image plane, and no virtual focus within the temperature range of-40 ℃ to 80 ℃ under the condition of small volume.

The third embodiment is as follows:

fig. 9 is a schematic view showing a zoom lens structure according to a third embodiment of the present invention.

Table 8 below lists relevant parameters of each lens of the present embodiment, including surface type, radius of curvature, thickness, refractive index of material, abbe number:

TABLE 8

Table 9 shows the aspherical surface coefficients of the aspherical lenses in the present embodiment, K is a conic constant of the surface, and A, B, C, D, E are aspherical surface coefficients of fourth order, sixth order, eighth order, tenth order, and twelfth order, respectively.

Number of noodles

K

A

B

C

D

E

S11

-10.356

0.00E+00

1.05E-5

-6.56E-8

2.89E-10

-5.23E-13

S12

1.025

0.00E+00

8.14E-5

-1.118E-7

2.65E-6

-7.206E-7

S13

-1.925

0.00E+00

8.21E-4

-9.15E-6

9.21E-10

-1.05E-12

S14

31.056

0.00E+00

-4.95E-4

2.89E-7

-4.21E-10

1.89E-13

S23

1.656

0.00E+00

8.14E-5

-1.12E-7

1.25E-10

-3.26E-11

S24

1.901

0.00E+00

3.375E-5

-1.18E-7

1.74E-10

-7.206E-7

TABLE 9

Table 10 lists the wide-angle end, telephoto end magnification variation data as follows:

thickness of	Wide angle end	Telescope end
			D1	0.710	17.351
D2	17.860	1.219
			D3	3.258	3.978
D4	2.484	1.764

Watch 10

Fig. 10 to 12 are diagrams illustrating an MTF chart at the wide-angle end at normal temperature of 20 ℃ under visible light, a defocus chart at the wide-angle end at low temperature of-40 ℃ under visible light, and a defocus chart at the wide-angle end at high temperature of 80 ℃ under visible light, respectively, of the zoom lens according to example 3. It can be known from the attached drawings that the zoom lens obtained according to embodiment 3 of the present invention has the characteristics of large aperture, high resolution, low distortion, large image plane, and no virtual focus within the temperature range of-40 ℃ to 80 ℃ under the condition of small volume.

The above description is only one embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A zoom lens characterized by comprising, in order in an object-side to image-side direction, a first fixed lens group (G1) having positive optical power, a first zoom lens group (G2) having negative optical power, a Stop (STO), a second fixed lens group (G3) having positive optical power, and a focus lens group (G4) having positive optical power;

the first zoom lens group (G2) includes, in order from the object side to the image side, a fourth lens (L4), a fifth lens (L5), a sixth lens (L6), and a seventh lens (L7).

2. The zoom lens according to claim 1, wherein the first fixed lens group (G1) includes, in order in an object-to-image direction, a first lens (L1) having negative optical power, a second lens (L2) having positive optical power, and a third lens (L3) having positive optical power.

3. The zoom lens according to claim 2, wherein the first lens (L1) and the third lens (L3) are each a concave-convex lens in an object-to-image direction.

4. A zoom lens according to claim 1, wherein the fifth lens (L5) has a negative optical power, and the sixth lens (L6) has a positive optical power.

5. The zoom lens according to claim 1, wherein the second fixed lens group (G3) includes, in order from the object side to the image side, an eighth lens (L8) having positive optical power, a ninth lens (L9) having positive optical power, a tenth lens (L10) having positive optical power, and an eleventh lens (L11) having negative optical power.

6. The zoom lens according to claim 5, wherein the eighth lens (L8) is an aspherical lens.

7. The zoom lens according to claim 5, wherein the ninth lens (L9) is a biconvex lens.

8. The zoom lens according to claim 1, wherein the focusing lens group (G4) includes, in order in an object-to-image direction, a twelfth lens (L12) having positive optical power, a thirteenth lens (L13) having negative optical power, a fourteenth lens (L14) having negative optical power, and a fifteenth lens (L15) having positive optical power.

9. A zoom lens according to any one of claims 5 to 7, wherein the refractive indices of the ninth lens (L9), the tenth lens (L10) and the eleventh lens (L11) are Nd9, Nd10 and Nd11, respectively, satisfying: nd9 is more than or equal to 1.45 and less than or equal to 1.65, Nd10 is more than Nd9, and Nd11 is more than Nd 9;

the abbe numbers of the ninth lens (L9), the tenth lens (L10) and the eleventh lens (L11) are Vd9, Vd10 and Vd11 respectively, and satisfy that: 62 < Vd9 < 65,30 < | Vd10-Vd11| < 60.

10. A zoom lens according to any one of claims 1 to 8, characterized in that each of the first fixed lens group (G1), first zoom lens group (G2), second fixed lens group (G3) and focusing lens group (G4) comprises at least one cemented lens group.

11. A zoom lens according to any one of claims 1 to 8, wherein the focal lengths of the first fixed lens group (G1), the first zoom lens group (G2), the second fixed lens group (G3) and the focusing lens group (G4) are f1, f2, f3 and f4, the zoom lens has a wide-angle end focal length fw, satisfying the relationship: f1/fw is more than or equal to 1.5 and less than or equal to 9, f2/fw is more than or equal to-5 and less than or equal to-0.5, f3/fw is more than or equal to 1 and less than or equal to 4.5, and f4/fw is more than or equal to 1.2 and less than or equal to 7.5.

12. A zoom lens according to any one of claims 1 to 8, wherein the position of the Stop (STO) satisfies: Ls/TTL is more than or equal to 0.35 and less than or equal to 0.46, wherein Ls represents the distance between the diaphragm and the image surface, and TTL represents the total length of the zoom lens optical system.

13. A zoom lens according to any one of claims 1 to 8, characterized in that the largest lens diameter in the first fixed lens group (G1) is

14. a zoom lens according to any one of claims 1 to 8, wherein the first zoom lens group (G2) is moved by a distance D from a wide angle end to a telephoto end, the total optical system length of the zoom lens is TTL, and the relationship: D/TTL is more than or equal to 0.2 and less than or equal to 0.3.