CN107422465B

CN107422465B - Optical imaging lens group

Info

Publication number: CN107422465B
Application number: CN201710865794.1A
Authority: CN
Inventors: 戴付建; 闻人建科; 李明
Original assignee: Zhejiang Sunny Optics Co Ltd
Current assignee: Zhejiang Sunny Optics Co Ltd
Priority date: 2017-09-22
Filing date: 2017-09-22
Publication date: 2022-09-16
Anticipated expiration: 2037-09-22
Also published as: CN107422465A

Abstract

The application discloses optical imaging lens group includes by thing side to image side in proper order: a first lens having a positive refractive power, an object-side surface of which is convex; the second lens with negative focal power, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; a third lens with focal power, wherein the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a concave surface; a fourth lens having a focal power, an object side surface of which is concave; a fifth lens having optical power; a sixth lens having optical power; a seventh lens having a negative refractive power, an image-side surface of which is concave; wherein, f/EPD between the effective focal length f of the optical imaging lens group and the entrance pupil diameter EPD of the optical imaging lens group is less than or equal to 1.7, and f7/f between the effective focal length f7 of the seventh lens and the effective focal length f of the optical imaging lens group is less than or equal to-1.0. The optical imaging lens group is suitable for portable electronic products, and has large aperture, good imaging quality and low sensitivity.

Description

Optical imaging lens group

Technical Field

The present invention relates to an optical imaging lens assembly, and more particularly to an optical imaging lens assembly comprising seven lenses.

Background

With the development of science and technology, the market demand for a camera lens suitable for portable electronic products is gradually increasing. Portable electronic products are increasingly tending to be miniaturized, which limits the overall length of the lens, thereby increasing the difficulty of designing the lens. The conventional photosensitive elements used in optical systems include an electric coupling device and a Complementary Metal Oxide Semiconductor (CMOS) element. With the improvement of the performance and the reduction of the size of the common photosensitive elements, corresponding requirements are put forward on the high imaging quality and the miniaturization of the camera lens used in cooperation.

In order to meet the requirement of miniaturization, the F number of the conventional lens is generally configured to be 2.0 or more than 2.0, so that the size reduction of the lens is realized and the lens has good optical performance. However, with the continuous development of portable electronic products such as smartphones, higher requirements are put forward on imaging lenses, especially for situations of insufficient light (such as overcast and rainy days, dusk, etc.) and shaking hands, so that the F number of 2.0 or more than 2.0 cannot meet higher-order imaging requirements.

Therefore, the invention provides an optical system which is applicable to portable electronic products, has large aperture, good imaging quality and low sensitivity.

Disclosure of Invention

To solve at least some of the problems of the prior art, the present invention provides an optical imaging lens assembly.

One aspect of the present invention provides an optical imaging lens assembly, sequentially from an object side to an image side, comprising: a first lens having a positive refractive power, an object-side surface of which is convex; the second lens with negative focal power, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; a third lens having a refractive power, the object-side surface of which is convex, and the image-side surface of which is concave; a fourth lens having a refractive power, an object-side surface of which is concave; a fifth lens having optical power; a sixth lens having optical power; a seventh lens having a negative refractive power, an image-side surface of which is concave; wherein, f/EPD between the effective focal length f of the optical imaging lens group and the entrance pupil diameter EPD of the optical imaging lens group is less than or equal to 1.7, and f7/f between the effective focal length f7 of the seventh lens and the effective focal length f of the optical imaging lens group is less than or equal to-1.0.

According to one embodiment of the invention, the effective focal length f1 of the first lens and the effective focal length f7 of the seventh lens satisfy: -1.5< f1/f7< -0.5.

According to one embodiment of the invention, the effective focal length f1 of the first lens and the curvature radius R2 of the image side surface of the first lens satisfy: 0.5< f1/R2< 1.5.

According to an embodiment of the invention, the on-axis distance T45 between the fourth lens and the fifth lens and the on-axis distance T12 between the first lens and the second lens are such that: 5< T45/T12< 11.

According to one embodiment of the invention, the effective focal length f1 of the first lens and the effective focal length f of the optical imaging lens group satisfy the following relationship: 1< f1/f < 2.

According to one embodiment of the invention, the effective focal length f2 of the second lens and the curvature radius R4 of the image side surface of the second lens satisfy: -6< f2/R4< -4.

According to an embodiment of the present invention, an air interval T12 of the first lens and the second lens on the optical axis and an air interval T67 of the sixth lens and the seventh lens on the optical axis satisfy: 10< T67/T12< 15.

According to one embodiment of the invention, the effective focal length f of the optical imaging lens group and the central thickness CT3 of the third lens satisfy the following relationship: 5< f/CT3< 9.

According to one embodiment of the invention, the effective focal length f4 of the optical imaging lens group and the curvature radius R7 of the object side surface of the fourth lens meet the following condition: -1. ltoreq. f 4/R7. ltoreq.1.5.

According to one embodiment of the invention, the effective focal length f2 of the second lens and the effective focal length f7 of the seventh lens satisfy the following condition: 1< f2/f7< 2.

One aspect of the present invention provides an optical imaging lens assembly, sequentially from an object side to an image side, comprising: a first lens having a positive refractive power, an object-side surface of which is convex; a second lens element having a negative refractive power, the object-side surface of the second lens element being convex and the image-side surface of the second lens element being concave; a third lens having a refractive power, the object-side surface of which is convex, and the image-side surface of which is concave; a fourth lens having a focal power, an object side surface of which is concave; a fifth lens having optical power; a sixth lens having optical power; a seventh lens having a negative refractive power, an image-side surface of which is concave; wherein an air interval T12 of the first lens and the second lens on the optical axis and an air interval T67 of the sixth lens and the seventh lens on the optical axis satisfy: 10< T67/T12<15, and an effective focal length f1 of the first lens and an effective focal length f7 of the seventh lens satisfy: -1.5< f1/f7< -0.5.

One aspect of the present invention provides an optical imaging lens assembly, sequentially from an object side to an image side, comprising: a first lens having a positive refractive power, an object-side surface of which is convex; the second lens with negative focal power, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; a third lens with focal power, wherein the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a concave surface; a fourth lens having a focal power, an object side surface of which is concave; a fifth lens having optical power; a sixth lens having a focal power; a seventh lens having a negative refractive power, an image-side surface of which is concave; wherein an effective focal length f1 of the first lens and an effective focal length f7 of the seventh lens satisfy: -1.5< f1/f7< -0.5.

One aspect of the present invention provides an optical imaging lens assembly, sequentially from an object side to an image side, comprising: a first lens having a positive refractive power, an object-side surface of which is convex; the second lens with negative focal power, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; a third lens with focal power, wherein the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a concave surface; a fourth lens having a focal power, an object side surface of which is concave; a fifth lens having optical power; a sixth lens having optical power; a seventh lens having a negative refractive power, an image-side surface of which is concave; wherein the effective focal length f1 of the first lens and the curvature radius R2 of the image side surface of the first lens satisfy: 0.5< f1/R2< 1.5.

One aspect of the present invention provides an optical imaging lens assembly, sequentially from an object side to an image side, comprising: a first lens having a positive refractive power, an object-side surface of which is convex; the second lens with negative focal power, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; a third lens having a refractive power, the object-side surface of which is convex, and the image-side surface of which is concave; a fourth lens having a focal power, an object side surface of which is concave; a fifth lens having optical power; a sixth lens having a focal power; a seventh lens having a negative refractive power, an image-side surface of which is concave; wherein an on-axis spacing T45 between the fourth lens and the fifth lens and an on-axis spacing T12 between the first lens and the second lens satisfies: 5< T45/T12< 11.

The optical imaging lens group is suitable for portable electronic products, and has large aperture, good imaging quality and low sensitivity.

Drawings

Other features, objects and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments thereof, when taken in conjunction with the accompanying drawings. In the drawings:

FIG. 1 is a schematic structural diagram of an optical imaging lens assembly of embodiment 1;

FIGS. 2 to 5 show an axial chromatic aberration curve, an astigmatism curve, a distortion curve and a magnification chromatic aberration curve, respectively, of the optical imaging lens assembly of example 1;

FIG. 6 is a schematic structural diagram of the optical imaging lens assembly of embodiment 2;

FIGS. 7 to 10 show the on-axis chromatic aberration curve, astigmatism curve, distortion curve and chromatic aberration of magnification curve of the optical imaging lens set of example 2;

FIG. 11 is a schematic structural diagram of the optical imaging lens assembly of embodiment 3;

FIGS. 12 to 15 show an axial chromatic aberration curve, an astigmatism curve, a distortion curve and a magnification chromatic aberration curve, respectively, of the optical imaging lens assembly of example 3;

FIG. 16 is the schematic diagram of the optical imaging lens assembly of embodiment 4;

FIGS. 17 to 20 show the on-axis chromatic aberration curve, astigmatism curve, distortion curve and chromatic aberration of magnification curve of the optical imaging lens set of example 4;

FIG. 21 is a schematic structural view of the optical imaging lens assembly of example 5;

FIGS. 22 to 25 show an axial chromatic aberration curve, an astigmatic curve, a distortion curve and a chromatic aberration of magnification curve, respectively, of the optical imaging lens assembly of example 5;

FIG. 26 is a schematic structural diagram of the optical imaging lens assembly of example 6;

FIGS. 27 to 30 show the on-axis chromatic aberration curve, astigmatism curve, distortion curve and chromatic aberration of magnification curve of the optical imaging lens set of example 6;

FIG. 31 is a schematic view of the optical imaging lens assembly of example 7; and

fig. 32 to 35 show an axial chromatic aberration curve, an astigmatism curve, a distortion curve and a chromatic aberration of magnification curve, respectively, of the optical imaging lens group of example 7.

Detailed Description

The present application will be described in further detail with reference to the following drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the relevant invention and not restrictive of the invention. It should be noted that, for convenience of description, only the portions related to the related invention are shown in the drawings.

It will be understood that when an element or layer is referred to herein as being "on," "connected to" or "coupled to" another element or layer, it can be directly on, connected or coupled to the other element or layer or intervening elements or layers may be present. When an element is referred to as being "directly on," "directly connected to" or "directly coupled to" another element or layer, there are no intervening elements or layers present. Like numbers refer to like elements throughout the specification. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

It will be understood that, although the

terms

1, 2, first, second, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the present application.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, features that are not limited to a single plural form are also intended to include plural forms of features unless the context clearly indicates otherwise. It will be further understood that the terms "comprises," "comprising," "includes," "including," "has," "having," "contains" and/or "containing," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items. A statement such as "at least one of" when appearing after a list of elements modifies the entire list of elements rather than modifying individual elements within the list. Furthermore, when describing embodiments of the present application, the use of "may" mean "one or more embodiments of the present application. Also, the term "exemplary" is intended to refer to examples or illustrations.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present application will be described in detail below with reference to the embodiments with reference to the attached drawings.

The application provides an optical imaging lens group, include in proper order by thing side to picture side: a first lens having a positive refractive power, the object-side surface of which is convex; the second lens with negative focal power, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; a third lens with focal power, wherein the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a concave surface; a fourth lens having a focal power, an object side surface of which is concave; a fifth lens having optical power; a sixth lens having optical power; and the image side surface of the seventh lens with negative focal power is a concave surface.

In the embodiment of the application, f/EPD between the effective focal length f of the optical imaging lens group and the entrance pupil diameter EPD of the optical imaging lens group is less than or equal to 1.7. More specifically, f/EPD ≦ 1.58 is satisfied. Through satisfying above-mentioned condition, the shape of each lens of rational distribution can make optical imaging lens group obtain more excellent formation of image and experience, when possessing the large aperture, can reduce the colour difference, reduce the distortion.

In the embodiment of the application, the effective focal length f7 of the seventh lens and the effective focal length f of the optical imaging lens group satisfy f7/f ≦ -1.0. More specifically, f 7/f.ltoreq.1.02 is satisfied. Through satisfying above-mentioned condition, the shape of each lens of rational distribution can make optical imaging lens group obtain more excellent formation of image and experience, when possessing the large aperture, can reduce the colour difference, reduce the distortion.

In the embodiments of the present application, the effective focal length f1 of the first lens and the effective focal length f7 of the seventh lens satisfy: -1.5< f1/f7< -0.5. More specifically, it satisfies-1.49. ltoreq. f1/f 7. ltoreq. 0.78. Through satisfying above-mentioned relation, can the focus of rational distribution first lens and seventh lens, be favorable to revising the optical distortion of system to promote the formation of image quality of camera lens.

In the embodiment of the application, the effective focal length f1 of the first lens and the curvature radius R2 of the image side surface of the first lens satisfy the following condition: 0.5< f1/R2< 1.5. More specifically, 0.55. ltoreq. f 1/R2. ltoreq.1.33 is satisfied. By satisfying the relationship, the curvature radius of the first lens can be controlled, so that the astigmatism contribution ratio of the first lens is in a reasonable range, the astigmatism of the system is effectively balanced, and the system obtains good imaging quality.

In an embodiment of the present application, an on-axis spacing T45 between the fourth lens and the fifth lens and an on-axis spacing T12 between the first lens and the second lens satisfy: 5< T45/T12< 11. More specifically, 5.57. ltoreq. T45/T12. ltoreq.10.87 is satisfied. By satisfying the above relationship, the air space between the lenses can be reasonably controlled, so that the system has both higher imaging quality and better processing characteristics.

In the embodiment of the present application, the effective focal length f1 of the first lens and the effective focal length f of the optical imaging lens set satisfy: 1< f1/f < 2. More specifically, 1.34. ltoreq. f 1/f. ltoreq.1.55 is satisfied. By satisfying the above conditions, the focal power of the first lens can be reasonably controlled, the primary spherical aberration of the system can be effectively corrected, and the processing characteristics of the first lens are ensured.

In the embodiment of the application, the effective focal length f2 of the second lens and the curvature radius R4 of the image side surface of the second lens satisfy the following condition: -6< f2/R4< -4. More specifically, it satisfies-5.84. ltoreq. f 2/R4. ltoreq. 4.48. By satisfying the above conditions, the curvature radius of the image side surface of the second lens can be reasonably configured, off-axis coma aberration and astigmatism can be effectively corrected, the light deflection angle of the system is reduced, and the sensitivity of the second lens is reduced.

In the embodiment of the present application, an air interval T12 of the first lens and the second lens on the optical axis and an air interval T67 of the sixth lens and the seventh lens on the optical axis satisfy: 10< T67/T12< 15. More specifically, 10.36. ltoreq. T67/T12. ltoreq.14.88 is satisfied. Through satisfying above-mentioned condition, can rationally control the air space between the lens to when guaranteeing that the system has higher imaging quality, can also possess better processing characteristic.

In the embodiment of the present application, the effective focal length f of the optical imaging lens group and the central thickness CT3 of the third lens satisfy: 5< f/CT3< 9. More specifically, 5.41. ltoreq. f/CT 3. ltoreq.8.31 is satisfied. By satisfying the above conditions, the center thickness of the third lens can be controlled, the system size can be effectively reduced, and the workability of the optical system can be ensured.

In the embodiments of the present application, the effective focal length f4 of the optical imaging lens group and the radius of curvature R7 of the object side of the fourth lens element satisfy: -1. ltoreq. f 4/R7. ltoreq.1.5. More specifically, it satisfies-0.94. ltoreq. f 4/R7. ltoreq.1.34. By meeting the conditions, the curvature radius of the fourth lens can be controlled, so that the astigmatism contribution ratio of the fourth lens is in a reasonable range, the astigmatism of the system is effectively balanced, and the system obtains good imaging quality.

In the embodiment of the present application, the effective focal length f2 of the second lens and the effective focal length f7 of the seventh lens satisfy: 1< f2/f7< 2. More specifically, 1.10. ltoreq. f2/f 7. ltoreq.1.89 is satisfied. By satisfying the above conditions, the effective focal lengths of the second lens and the seventh lens can be reasonably controlled, the vertical axis chromatic aberration of the system can be reduced, and the optical characteristics of a large aperture can be realized.

The present application is further described below with reference to specific examples.

Example 1

An optical imaging lens set according to embodiment 1 of the present application is described first with reference to fig. 1 to 5.

Fig. 1 is a schematic structural diagram illustrating an optical imaging lens assembly of embodiment 1. As shown in FIG. 1, the optical imaging lens assembly includes 7 lenses. The 7 lenses are a first lens E1 having an object side surface S1 and an image side surface S2, a second lens E2 having an object side surface S3 and an image side surface S4, a third lens E3 having an object side surface S5 and an image side surface S6, a fourth lens E4 having an object side surface S7 and an image side surface S8, a fifth lens E5 having an object side surface S9 and an image side surface S10, a sixth lens E6 having an object side surface S11 and an image side surface S12, and a seventh lens E7 having an object side surface S13 and an image side surface S14, respectively. The first lens element E1 through the seventh lens element E7 are disposed in order from an object side to an image side of the optical imaging lens assembly.

The first lens element E1 may have positive power, and the object-side surface S1 may be convex and the image-side surface S2 may be concave.

The second lens element E2 may have a negative power, and the object-side surface S3 may be convex and the image-side surface S4 may be concave.

The third lens element E3 may have positive power, and the object-side surface S5 may be convex and the image-side surface S6 may be concave.

The fourth lens element E4 may have a negative power, and its object-side surface S7 may be concave and its image-side surface S8 may be concave.

The fifth lens element E5 may have positive power, and its object-side surface S9 may be concave and its image-side surface S10 may be convex.

The sixth lens element E6 may have positive power, and the object-side surface S11 may be convex and the image-side surface S12 may be concave.

The seventh lens element E7 can have a negative power, and its object-side surface S13 can be convex and its image-side surface S14 can be concave.

The optical imaging lens group further comprises a filter E8 which is used for filtering infrared light and provided with an object side surface S15 and an image side surface S16. In this embodiment, light from the object passes through the respective surfaces S1 to S16 in order and is finally imaged on the imaging surface S17.

In this embodiment, the first lens E1 through the seventh lens E7 have respective effective focal lengths f1 through f7, respectively. The first lens element E1 through the seventh lens element E7 are arranged along the optical axis in sequence and jointly determine the total effective focal length f of the optical imaging lens assembly. The following table 1 shows the effective focal lengths f1 to f7 of the first lens element E1 to the seventh lens element E7, the total effective focal length f of the optical imaging lens assembly, the total length ttl (mm) of the optical imaging lens assembly, and a half of the diagonal ImgH of the effective pixel area of the electro-optic sensor.

f1(mm)	5.32	f(mm)	3.98
				f2(mm)	-7.53	TTL(mm)	4.95
f3(mm)	5.06	ImgH(mm)	3.40
				f4(mm)	-29.33
f5(mm)	17.20
				f6(mm)	46.37
f7(mm)	-6.84

TABLE 1

Table 2 shows the surface type, radius of curvature, thickness, material and conic coefficient of each lens element of the optical imaging lens assembly in this embodiment, wherein the radius of curvature and the thickness are both in millimeters (mm).

TABLE 2

In the present embodiment, each lens may be an aspheric lens, and each aspheric surface type x is defined by the following formula:

wherein x is the rise of the distance from the aspheric surface vertex to the aspheric surface vertex when the aspheric surface is at the position with the height of h along the optical axis direction; c is the paraxial curvature of the aspheric surface, c being 1/R (i.e., paraxial curvature c is the inverse of radius of curvature R in table 1 above); k is the conic coefficient (given in table 2); ai is the correction coefficient of the i-th order of the aspherical surface.

Table 3 below shows high-order term coefficients of the respective aspherical surfaces S1 to S14 usable for the respective aspherical lenses in this embodiment.

Flour mark

A4

A6

A8

A10

A12

A14

A16

A18

A20

S1

-1.2184E-02

5.4347E-03

-5.5520E-02

7.4028E-02

-6.0105E-02

1.9479E-02

-1.9951E-03

0.0000E+00

S2

4.4116E-02

-1.5786E-01

4.6953E-02

8.6499E-02

-9.4928E-02

3.7178E-02

-5.2983E-03

0.0000E+00

S3

-5.6011E-02

1.4247E-02

-1.9693E-01

3.8590E-01

-3.0080E-01

1.1474E-01

-1.8117E-02

0.0000E+00

S4

-1.9839E-01

2.6128E-01

-5.7849E-01

8.5890E-01

-7.6296E-01

3.9403E-01

-9.2796E-02

0.0000E+00

S5

-2.7392E-02

8.5048E-02

-1.8388E-01

1.7173E-01

-6.0047E-02

2.2376E-02

-7.1971E-03

0.0000E+00

S6

-1.1238E-02

-7.9792E-02

2.9298E-01

-6.7872E-01

8.4901E-01

-5.2604E-01

1.3246E-01

0.0000E+00

S7

-1.2093E-01

-8.5414E-03

2.7185E-04

-7.8033E-02

1.7828E-01

-1.1634E-01

1.8404E-02

0.0000E+00

S8

-7.3141E-02

-2.2281E-02

1.5714E-01

-5.4041E-01

7.0869E-01

-3.9650E-01

8.1181E-02

0.0000E+00

S9

9.6779E-02

-1.8139E-02

5.4687E-02

-4.1437E-01

5.2440E-01

-2.5720E-01

4.4574E-02

0.0000E+00

S10

-5.6864E-02

1.4318E-01

-1.2585E-02

-3.1781E-01

4.3145E-01

-2.7968E-01

1.0450E-01

-2.1735E-02

1.9304E-03

S11

-1.5798E-01

1.1707E-01

-1.1536E-01

3.7228E-02

-3.5533E-03

0.0000E+00

S12

-1.4906E-01

9.7947E-02

-7.3680E-02

2.8369E-02

-5.1448E-03

3.5422E-04

0.0000E+00

S13

-4.4443E-01

2.5004E-01

-6.5690E-02

7.0815E-03

8.6014E-04

-4.4360E-04

7.4545E-05

-6.3160E-06

2.2242E-07

S14

-2.8912E-01

2.1041E-01

-1.1587E-01

4.8937E-02

-1.4452E-02

2.7697E-03

-3.2444E-04

2.1072E-05

-5.8211E-07

TABLE 3

Fig. 2 shows an on-axis aberration curve of the optical imaging lens group of example 1, which represents the deviation of the convergent focus of light rays of different wavelengths after passing through the optical system. FIG. 3 is an astigmatism curve representing meridional and sagittal field curvatures for the optical imaging lens assembly of example 1. FIG. 4 is a distortion curve for the optical imaging lens assembly of example 1 showing the distortion magnitude at different viewing angles. FIG. 5 is a chromatic aberration of magnification curve of the optical imaging lens assembly of example 1, which shows the deviation of different image heights of light rays passing through the optical imaging lens assembly on the image plane. In summary, referring to fig. 2 to 5, it can be seen that the optical imaging lens assembly of embodiment 1 is suitable for portable electronic products, and has a large aperture, good imaging quality and low sensitivity.

Example 2

An optical imaging lens set according to embodiment 2 of the present application is described below with reference to fig. 6 to 10.

FIG. 6 is a schematic diagram showing the structure of the optical imaging lens assembly of embodiment 2. As shown in FIG. 6, the optical imaging lens assembly includes 7 lenses. The 7 lenses are a first lens E1 having an object side surface S1 and an image side surface S2, a second lens E2 having an object side surface S3 and an image side surface S4, a third lens E3 having an object side surface S5 and an image side surface S6, a fourth lens E4 having an object side surface S7 and an image side surface S8, a fifth lens E5 having an object side surface S9 and an image side surface S10, a sixth lens E6 having an object side surface S11 and an image side surface S12, and a seventh lens E7 having an object side surface S13 and an image side surface S14, respectively. The first lens element E1 through the seventh lens element E7 are disposed in order from an object side to an image side of the optical imaging lens assembly.

The first lens element E1 can have positive power, and its object-side surface S1 can be convex and its image-side surface S2 can be concave.

The fourth lens element E4 may have positive power, and its object-side surface S7 may be concave and its image-side surface S8 may be convex.

The sixth lens element E6 may have negative power, and the object-side surface S11 may be convex and the image-side surface S12 may be concave.

The seventh lens element E7 may have a negative power, and the object side surface S13 may be concave and the image side surface S14 may be concave.

The following table 4 shows the effective focal lengths f1 to f7 of the first lens element E1 to the seventh lens element E7, the total effective focal length f of the optical imaging lens assembly, the total length TTL of the optical imaging lens assembly, and a half ImgH of the diagonal length of the effective pixel area of the electro-optic sensor.

TABLE 4

Table 5 shows the surface type, radius of curvature, thickness, material and conic coefficient of each lens in the optical imaging lens group in this embodiment, wherein the unit of the radius of curvature and the thickness are both millimeters (mm).

TABLE 5

Table 6 below shows high-order term coefficients of the respective aspherical surfaces S1 to S14 usable for the respective aspherical lenses in this embodiment. Wherein each aspherical surface type can be defined by the formula (1) given in the above-described embodiment 1.

TABLE 6

FIG. 7 is a graph showing the on-axis aberration curves of the optical imaging lens assembly of example 2, which shows the deviation of the convergent focus of light rays of different wavelengths after passing through the optical system. FIG. 8 shows the astigmatism curves of the optical imaging lens group of example 2 representing meridional field curvature and sagittal field curvature. FIG. 9 is a distortion curve for the optical imaging lens assembly of example 2 showing the distortion magnitude at different viewing angles. Fig. 10 shows a chromatic aberration of magnification curve of the optical imaging lens assembly of example 2, which shows the deviation of different image heights of light rays passing through the optical imaging lens assembly on the imaging plane. In summary, and referring to fig. 7 to 10, the optical imaging lens assembly of embodiment 2 is suitable for portable electronic products, and has a large aperture, good imaging quality and low sensitivity.

Example 3

An optical imaging lens set according to embodiment 3 of the present application is described below with reference to fig. 11 to 15.

FIG. 11 is a schematic diagram showing the structure of the optical imaging lens assembly of embodiment 3. The optical imaging lens group comprises a first lens element E1, a second lens element E2, a third lens element E3, a fourth lens element E4, a fifth lens element E5, a sixth lens element E6 and a seventh lens element E7 in order from an object side to an image side.

The fifth lens element E5 may have positive power, and the object-side surface S9 may be concave and the image-side surface S10 may be convex.

The following table 7 shows the effective focal lengths f1 to f7 of the first lens element E1 to the seventh lens element E7, the total effective focal length f of the optical imaging lens assembly, the total length TTL of the optical imaging lens assembly, and a half of the diagonal ImgH of the effective pixel area of the electro-optic sensor.

f1(mm)	5.25	f(mm)	3.56
				f2(mm)	-6.26	TTL(mm)	4.50
f3(mm)	3.89	ImgH(mm)	2.77
				f4(mm)	42.27
f5(mm)	4.96
				f6(mm)	-9.21
f7(mm)	-3.64

TABLE 7

Table 8 shows the surface type, radius of curvature, thickness, material and conic coefficient of each lens element of the optical imaging lens assembly in this example, wherein the radius of curvature and the thickness are both in millimeters (mm).

TABLE 8

Table 9 below shows high-order term coefficients of each aspherical surface S1 to S14 usable for each aspherical lens in this embodiment, wherein each aspherical surface type can be defined by formula (1) given in embodiment 1 above.

TABLE 9

FIG. 12 is a graph showing the on-axis aberration curves of the optical imaging lens assembly of example 3, which shows the deviation of the convergent focus of light rays of different wavelengths after passing through the optical system. FIG. 13 is an astigmatism curve representing meridional field curvature and sagittal field curvature for the optical imaging lens assembly of example 3. FIG. 14 shows the distortion curve of the optical imaging lens assembly of example 3, which represents the distortion magnitude at different viewing angles. Fig. 15 shows a chromatic aberration of magnification curve of the optical imaging lens assembly of example 3, which represents the deviation of different image heights of light rays on the imaging plane after passing through the optical imaging lens assembly. In summary, as can be seen from fig. 12 to 15, the optical imaging lens assembly of embodiment 3 is suitable for portable electronic products, and has a large aperture, good imaging quality and low sensitivity.

Example 4

An optical imaging lens set according to embodiment 4 of the present application is described below with reference to fig. 16 to 20.

FIG. 16 is a schematic diagram showing the structure of the optical imaging lens assembly of embodiment 4. The optical imaging lens group comprises a first lens element E1, a second lens element E2, a third lens element E3, a fourth lens element E4, a fifth lens element E5, a sixth lens element E6 and a seventh lens element E7 in order from an object side to an image side.

The following table 10 shows the effective focal lengths f1 to f7 of the first lens element E1 to the seventh lens element E7, the total effective focal length f of the optical imaging lens assembly, the total length TTL of the optical imaging lens assembly, and a half ImgH of the diagonal length of the effective pixel area of the electro-optic sensor.

f1(mm)	5.33	f(mm)	3.65
				f2(mm)	-6.11	TTL(mm)	4.58
f3(mm)	3.73	ImgH(mm)	2.86
				f4(mm)	52.23
f5(mm)	10.43
				f6(mm)	-15.15
f7(mm)	-4.75

Watch 10

Table 11 below shows the surface type, radius of curvature, thickness, material and conic coefficient of each lens in the optical imaging lens group in this embodiment, wherein the unit of the radius of curvature and the thickness are both millimeters (mm).

TABLE 11

Table 12 below shows the high-order term coefficients of the respective aspherical surfaces S1 to S14 usable for the respective aspherical lenses in this embodiment, wherein the respective aspherical surface types can be defined by formula (1) given in example 1 above.

Flour mark

A4

A6

A8

A10

A12

A14

A16

A18

A20

S1

3.8274E-03

1.5941E-03

-5.4261E-02

1.0538E-01

-1.0973E-01

5.9079E-02

-1.3046E-02

0.0000E+00

S2

8.5386E-02

-7.8636E-02

-3.9122E-02

2.3893E-01

-3.0275E-01

1.7948E-01

-4.3347E-02

0.0000E+00

S3

7.5042E-02

-1.1271E-01

-1.5566E-02

2.3077E-01

-2.9212E-01

1.6408E-01

-3.7719E-02

0.0000E+00

S4

-2.9504E-02

1.4008E-01

-3.2532E-01

4.5499E-01

-3.6866E-01

1.5054E-01

-2.4814E-02

0.0000E+00

S5

-3.1689E-02

5.7570E-02

-7.5956E-02

8.8761E-02

-6.5487E-02

2.7392E-02

-5.3555E-03

0.0000E+00

S6

-7.6659E-02

-2.2243E-02

1.3987E-01

-3.0285E-01

3.8044E-01

-2.4134E-01

5.8858E-02

0.0000E+00

S7

-2.2921E-01

-1.4495E-01

3.1536E-01

-3.3031E-01

4.2322E-01

-3.8084E-01

1.2870E-01

0.0000E+00

S8

-1.3030E-01

-2.4285E-01

2.2207E-01

1.3208E-01

-2.5866E-01

1.0570E-01

-8.2085E-03

0.0000E+00

S9

3.3337E-01

-5.0518E-01

2.5329E-01

1.1181E-02

-6.6346E-02

0.0000E+00

S10

1.6188E-01

1.4583E-02

-2.3096E-01

3.0253E-01

-5.5876E-01

8.2233E-01

-6.7440E-01

2.7742E-01

-4.4842E-02

S11

-2.9988E-01

2.3232E-01

-1.9590E-01

4.7895E-02

-1.5329E-03

0.0000E+00

S12

-2.8035E-01

2.0086E-01

-1.3339E-01

5.3117E-02

-1.1017E-02

9.2951E-04

0.0000E+00

S13

-1.5636E-01

5.2528E-02

4.1191E-02

-3.6857E-02

1.2133E-02

-1.7861E-03

3.7217E-05

1.9679E-05

-1.6524E-06

S14

-1.0860E-01

7.2674E-02

-4.1117E-02

2.1403E-02

-8.2874E-03

2.0611E-03

-3.0662E-04

2.4839E-05

-8.4385E-07

TABLE 12

FIG. 17 is a graph showing the on-axis aberration curves of the optical imaging lens assembly of example 4, which shows the deviation of the convergent focus of light rays of different wavelengths after passing through the optical system. FIG. 18 is an astigmatism curve representing meridional and sagittal field curvatures for the optical imaging lens assembly of example 4. FIG. 19 shows the distortion curve for the optical imaging lens set of example 4 showing the distortion magnitude for different viewing angles. Fig. 20 shows a chromatic aberration of magnification curve of the optical imaging lens assembly of example 4, which represents the deviation of different image heights of light rays passing through the optical imaging lens assembly on the image plane. In summary, as can be seen from fig. 17 to 20, the optical imaging lens assembly of embodiment 4 is suitable for portable electronic products, and has a large aperture, good imaging quality and low sensitivity.

Example 5

An optical imaging lens set according to embodiment 5 of the present application is described below with reference to fig. 21 to 25.

FIG. 21 is a schematic diagram showing the structure of the optical imaging lens assembly of embodiment 5. The optical imaging lens group includes, in order from an object side to an image side, a first lens element E1, a second lens element E2, a third lens element E3, a fourth lens element E4, a fifth lens element E5, a sixth lens element E6 and a seventh lens element E7.

The fourth lens element E4 may have negative power, and the object-side surface S7 may be concave and the image-side surface S8 may be concave.

The sixth lens element E6 may have negative power, and the object-side surface S9 may be convex and the image-side surface S10 may be concave.

The following table 13 shows the effective focal lengths f1 to f7 of the first lens element E1 to the seventh lens element E7, the total effective focal length f of the optical imaging lens assembly, the total length TTL of the optical imaging lens assembly and half of the diagonal ImgH of the effective pixel area of the electro-optic sensor.

Watch 13

Table 14 below shows the surface type, radius of curvature, thickness, material and conic coefficient of each lens element of the optical imaging lens assembly in this embodiment, wherein the radius of curvature and the thickness are both in millimeters (mm).

TABLE 14

Table 15 below shows the high-order term coefficients of the respective aspherical surfaces S1 to S14 usable for the respective aspherical lenses in this embodiment, wherein the respective aspherical surface types can be defined by formula (1) given in example 1 above.

Watch 15

FIG. 22 is a graph showing the on-axis aberration curves of the optical imaging lens assembly of example 5, which shows the deviation of the convergent focus of light rays of different wavelengths after passing through the optical system. FIG. 23 is an astigmatism curve representing meridional field curvature and sagittal field curvature for the optical imaging lens assembly of example 5. FIG. 24 is a distortion curve for the optical imaging lens assembly of example 5 showing the distortion magnitude at different viewing angles. FIG. 25 is a chromatic aberration of magnification curve for the optical imaging lens assembly of example 5 showing the deviation of different image heights of light rays passing through the optical imaging lens assembly on the image plane. In summary, as can be seen from fig. 22 to 25, the optical imaging lens assembly of embodiment 5 is suitable for portable electronic products, and has a large aperture, good imaging quality and low sensitivity.

Example 6

An optical imaging lens assembly according to embodiment 6 of the present application is described below with reference to fig. 26 to 30.

Fig. 26 is a schematic diagram showing the structure of the optical imaging lens assembly of embodiment 6. The optical imaging lens group comprises a first lens element E1, a second lens element E2, a third lens element E3, a fourth lens element E4, a fifth lens element E5, a sixth lens element E6 and a seventh lens element E7 in order from an object side to an image side.

The first lens element E1 may have positive optical power, and its object-side surface S1 may be convex and its image-side surface S2 may be concave.

The following table 16 shows the effective focal lengths f1 to f7 of the first lens element E1 to the seventh lens element E7, the total effective focal length f of the optical imaging lens assembly, the total length TTL of the optical imaging lens assembly and half ImgH of the diagonal length of the effective pixel area of the electro-optic sensor.

f1(mm)	5.13	f(mm)	3.45
				f2(mm)	-7.12	TTL(mm)	4.58
f3(mm)	4.64	ImgH(mm)	2.55
				f4(mm)	-29.62
f5(mm)	4.46
				f6(mm)	-19.50
f7(mm)	-3.77

TABLE 16

Table 17 below shows the surface type, radius of curvature, thickness, material and conic coefficient of each lens in the optical imaging lens group in this embodiment, wherein the unit of the radius of curvature and the thickness are both millimeters (mm).

TABLE 17

Table 18 below shows the high-order term coefficients of the respective aspherical surfaces S1 to S14 usable for the respective aspherical lenses in this embodiment, wherein the respective aspherical surface types can be defined by formula (1) given in example 1 above.

Flour mark

A4

A6

A8

A10

A12

A14

A16

A18

A20

S1

8.0378E-03

-1.4641E-02

2.1423E-03

-1.4230E-04

5.0045E-06

-9.0595E-08

6.6900E-10

0.0000E+00

S2

4.2820E-15

-3.7977E-14

1.3576E-13

-2.4131E-13

2.2898E-13

-1.1119E-13

2.1735E-14

0.0000E+00

S3

-5.6401E-02

1.9172E-02

1.1153E-04

1.0126E-02

-2.2002E-02

9.0932E-03

-9.4967E-04

0.0000E+00

S4

-8.5639E-02

5.4766E-02

-1.0687E-02

-5.4874E-03

-1.9557E-02

1.6419E-02

-3.3691E-03

0.0000E+00

S5

-3.9049E-03

-3.7337E-04

2.2563E-05

-3.8592E-07

2.9525E-09

-1.0892E-11

5.0012E-14

0.0000E+00

S6

-7.2541E-02

-7.5452E-03

-1.0743E-02

1.8859E-02

-9.4159E-03

1.9935E-03

-1.5361E-04

0.0000E+00

S7

-2.1464E-01

-3.5600E-02

1.0429E-01

-2.5567E-01

4.7564E-01

-3.8983E-01

1.1318E-01

0.0000E+00

S8

-1.5448E-01

-3.2482E-02

-3.8928E-03

-1.0971E-02

1.4372E-01

-1.5071E-01

4.4859E-02

0.0000E+00

S9

7.7686E-02

-8.0695E-02

-1.1926E-01

1.5372E-01

-6.4582E-02

0.0000E+00

S10

6.8520E-02

-1.1942E-02

-2.2339E-02

9.9080E-03

-1.8496E-03

1.8747E-04

-1.0776E-05

3.3111E-07

-4.2342E-09

S11

-1.5954E-01

-4.3482E-02

6.4787E-02

-4.7793E-02

8.6177E-03

0.0000E+00

S12

-2.1687E-01

2.3235E-02

1.5091E-02

-1.4482E-02

4.7254E-03

-5.3685E-04

0.0000E+00

S13

-4.7024E-01

2.5719E-01

-8.5694E-03

-4.1864E-02

1.9609E-02

-4.4528E-03

5.6777E-04

-3.8900E-05

1.1154E-06

S14

-2.6585E-01

1.9116E-01

-7.3394E-02

1.6723E-02

-2.3046E-03

1.9091E-04

-9.2807E-06

2.4397E-07

-2.6785E-09

Watch 18

FIG. 27 is a graph showing the on-axis aberration curves of the optical imaging lens assembly of example 6, showing the deviation of the convergent focus of light rays of different wavelengths through the optical system. FIG. 28 is an astigmatism curve representing meridional and sagittal field curvatures for the optical imaging lens assembly of example 6. Fig. 29 shows the distortion curve for the optical imaging lens assembly of example 6, which represents the distortion magnitude for different viewing angles. FIG. 30 is a chromatic aberration of magnification curve for the optical imaging lens assembly of example 6 showing the deviation of different image heights of light rays passing through the optical imaging lens assembly on the image plane. In summary, and referring to fig. 27 to 30, it can be seen that the optical imaging lens assembly of embodiment 6 is suitable for portable electronic products, and has a large aperture, good imaging quality and low sensitivity.

Example 7

An optical imaging lens group according to embodiment 7 of the present application is described below with reference to fig. 31 to 35.

FIG. 31 is a schematic diagram showing the structure of the optical imaging lens assembly of example 7. The optical imaging lens group includes, in order from an object side to an image side, a first lens element E1, a second lens element E2, a third lens element E3, a fourth lens element E4, a fifth lens element E5, a sixth lens element E6 and a seventh lens element E7.

The following table 19 shows the effective focal lengths f1 to f7 of the first lens element E1 to the seventh lens element E7, the total effective focal length f of the optical imaging lens assembly, the total length TTL of the optical imaging lens assembly and half of the diagonal ImgH of the effective pixel area of the electro-optic sensor.

f1(mm)	5.05	f(mm)	3.48
				f2(mm)	-6.85	TTL(mm)	4.58
f3(mm)	4.63	ImgH(mm)	2.58
				f4(mm)	-67.14
f5(mm)	4.84
				f6(mm)	-16.96
f7(mm)	-3.77

Watch 19

Table 20 below shows the surface type, radius of curvature, thickness, material and conic coefficient of each lens in the optical imaging lens group in this embodiment, wherein the unit of the radius of curvature and the thickness are both millimeters (mm).

Watch 20

Table 21 below shows the high-order term coefficients of the respective aspherical surfaces S1 to S14 usable for the respective aspherical lenses in this embodiment, wherein the respective aspherical surface types can be defined by formula (1) given in the above-described embodiment 1.

TABLE 21

FIG. 32 is a graph showing the on-axis aberration curves of the optical imaging lens assembly of example 7, which shows the deviation of the convergent focus of light rays of different wavelengths after passing through the optical system. FIG. 33 shows the astigmatism curves representing meridional and sagittal image planes curvature of the optical imaging lens group of example 7. FIG. 34 is a distortion curve for the optical imaging lens assembly of example 7 showing the magnitude of distortion at different viewing angles. FIG. 35 is a chromatic aberration of magnification curve for the optical imaging lens assembly of example 7 showing the deviation of different image heights of light rays passing through the optical imaging lens assembly on the image plane. In summary, referring to fig. 31 to 35, it can be seen that the optical imaging lens assembly of embodiment 7 is suitable for portable electronic products, and has a large aperture, good imaging quality and low sensitivity.

In summary, in the above examples 1 to 7, each conditional expression satisfies the conditions of the following table 22.

Conditions/examples	1	2	3	4	5	6	7
								f/EPD	1.55	1.56	1.58	1.54	1.51	1.47	1.49
f7/f	-1.72	-1.04	-1.02	-1.30	-1.09	-1.10	-1.08
								f1/f	1.34	1.55	1.47	1.46	1.40	1.49	1.45
f2/R4	-4.48	-5.84	-5.22	-5.23	-5.21	-5.73	-5.37
								T67/T12	10.36	11.32	12.39	14.04	14.88	14.38	14.65
f/CT3	8.31	5.68	5.67	5.41	7.15	6.53	6.73
								f4/R7	1.34	-0.94	-0.08	-0.83	0.33	0.06	0.15
f2/f7	1.10	1.88	1.72	1.29	1.81	1.89	1.81
								f1/f7	-0.78	-1.49	-1.44	-1.12	-1.28	-1.36	-1.34
f1/R2	1.33	1.26	1.16	0.99	0.55	0.59	0.56
								T45/T12	5.57	10.36	10.87	9.71	7.74	8.09	10.33

TABLE 22

The above description is only a preferred embodiment of the application and is illustrative of the principles of the technology employed. It will be appreciated by a person skilled in the art that the scope of the invention according to the present application is not limited to the specific combination of the above-mentioned features, but also covers other embodiments where any combination of the above-mentioned features or their equivalents is made without departing from the inventive concept. For example, the above features may be replaced with (but not limited to) features having similar functions disclosed in the present application.

Claims

1. An optical imaging lens assembly includes, in order from an object side to an image side:

a first lens having a positive refractive power, the object-side surface of which is convex;

the second lens with negative focal power, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface;

a third lens with positive focal power, wherein the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a concave surface;

a fourth lens having a refractive power, an object-side surface of which is concave;

a fifth lens having a positive optical power;

a sixth lens having optical power;

a seventh lens having a negative refractive power, an image-side surface of which is concave; and

the number of the lenses with optical power in the optical imaging lens group is seven,

wherein f/EPD between the effective focal length f of the optical imaging lens group and the entrance pupil diameter EPD of the optical imaging lens group is equal to or less than 1.7, f7/f is equal to or less than-1.0 between the effective focal length f7 of the seventh lens and the effective focal length f of the optical imaging lens group, and 10< T67/T12<15 between the air interval T12 of the first lens and the second lens on the optical axis and the air interval T67 of the sixth lens and the seventh lens on the optical axis.

2. The set of optical imaging lenses of claim 1, wherein an effective focal length f1 of the first lens and an effective focal length f7 of the seventh lens satisfy: -1.5< f1/f7< -0.5.

3. The set of optical imaging lenses of claim 1, wherein an effective focal length f1 of the first lens element and a radius of curvature R2 of the image side surface of the first lens element satisfy: 0.5< f1/R2< 1.5.

4. The set of optical imaging lenses of claim 1, wherein an on-axis spacing T45 between the fourth and fifth lenses and an on-axis spacing T12 between the first and second lenses satisfies: 5< T45/T12< 11.

5. The set of optical imaging lenses of any one of claims 1 to 4, wherein an effective focal length f1 of the first lens element and an effective focal length f of the set of optical imaging lenses satisfy: 1< f1/f < 2.

6. The set of optical imaging lenses of any one of claims 1-4, wherein an effective focal length f2 of the second lens element and a radius of curvature R4 of an image side surface of the second lens element satisfy: -6< f2/R4< -4.

7. The set of optical imaging lenses of claim 2, wherein the effective focal length f of the set of optical imaging lenses and the center thickness CT3 of the third lens satisfy: 5< f/CT3< 9.

8. The set of optical imaging lenses of claim 2, wherein an effective focal length f4 of the fourth lens element and a radius of curvature R7 of an object-side surface of the fourth lens element satisfy: -1. ltoreq. f 4/R7. ltoreq.1.5.

9. The set of optical imaging lenses of claim 1, wherein an effective focal length f2 of the second lens and an effective focal length f7 of the seventh lens satisfy: 1< f2/f7< 2.

10. An optical imaging lens assembly includes, in order from an object side to an image side:

a first lens having a positive refractive power, an object-side surface of which is convex;

a third lens element having a positive refractive power, the object-side surface of which is convex and the image-side surface of which is concave;

a fourth lens having a focal power, an object side surface of which is concave;

a fifth lens having a positive optical power;

a sixth lens having optical power;

wherein an air interval T12 of the first lens and the second lens on the optical axis and an air interval T67 of the sixth lens and the seventh lens on the optical axis satisfy: 10< T67/T12<15, an effective focal length f1 of the first lens and an effective focal length f7 of the seventh lens satisfying: -1.5< f1/f7< -0.5, and the effective focal length f of the optical imaging lens group and the central thickness CT3 of the third lens satisfy: 5< f/CT3< 9.

11. The set of optical imaging lenses of claim 10, wherein an effective focal length f1 of the first lens element and a radius of curvature R2 of the image side surface of the first lens element satisfy: 0.5< f1/R2< 1.5.

12. The set of optical imaging lenses of claim 10, wherein an on-axis spacing T45 between the fourth and fifth lenses and an on-axis spacing T12 between the first and second lenses satisfies: 5< T45/T12< 11.

13. The set of optical imaging lenses of claim 10, wherein the effective focal length f1 of the first lens element and the effective focal length f of the set of optical imaging lenses satisfy: 1< f1/f < 2.

14. The set of optical imaging lenses of any one of claims 10 to 13, wherein an effective focal length f2 of the second lens element and a radius of curvature R4 of an image side surface of the second lens element satisfy: -6< f2/R4< -4.

15. The set of optical imaging lenses of any one of claims 10 to 13, wherein an effective focal length f4 of the fourth lens element and a radius of curvature R7 of an object-side surface of the fourth lens element satisfy: -1. ltoreq. f 4/R7. ltoreq.1.5.

16. The set of optical imaging lenses of any one of claims 10 to 13, wherein an effective focal length f2 of the second lens and an effective focal length f7 of the seventh lens satisfy: 1< f2/f7< 2.

17. The optical imaging lens group of claim 10 wherein the effective focal length f of said optical imaging lens group satisfies f/EPD ≦ 1.7 for the entrance pupil diameter EPD of said optical imaging lens group and the effective focal length f7 of said seventh lens and the effective focal length f of said optical imaging lens group satisfies f7/f ≦ -1.0.