CN106154507B - Imaging lens assembly, image capturing device and electronic device - Google Patents

Abstract

An imaging lens group, an imaging device and an electronic device, wherein the imaging lens group includes a first lens, a second lens, a third lens and a fourth lens in order from the object side to the image side. The first lens has positive refractive power, and its object side surface is convex near the axis. The second lens has negative refractive power, and its object side surface is concave near the axis. The third lens has positive refractive power, and its object side surface and image side surface are both aspherical. The fourth lens has refractive power, and its object side surface and image side surface are both aspherical. When specific conditions are met, the camera range can be effectively suppressed, so that the imaging quality of the local image has a higher resolution. The present invention also discloses an imaging device and an electronic device.

Description

Imaging lens group, imaging device and electronic device

technical field

The invention relates to an imaging lens group and an image capturing device, in particular to a miniaturized imaging lens group and an image capturing device applied to an electronic device.

Background technique

In recent years, with the rise of electronic products with photographic functions, the demand for optical systems has increased day by day. The photosensitive element of a general optical system is nothing more than a charge coupled device (Charge Coupled Device, CCD) or a complementary metal oxide semiconductor sensor (Complementary Metal-Oxide Semiconductor Sensor, CMOS sensor). With the advancement of semiconductor technology, The pixel size of the photosensitive element is reduced, and the optical system is gradually developing into the high-pixel field, so the requirements for imaging quality are also increasing.

At present, most of the lenses configured in the portable electronic devices on the market pursue close-object distance and wide-angle shooting effects, but the optical design of such lenses cannot meet the needs of capturing distant and subtle images. The traditional telephoto optical system mostly adopts a multi-chip structure and is equipped with a spherical glass lens. This kind of configuration not only makes the lens too bulky to be carried easily, but also the high unit price of the product also discourages consumers. Therefore, The optical system in the prior art can no longer meet the photography needs of the general consumers in pursuit of convenience and multi-function.

Contents of the invention

The technical problem to be solved by the present invention is to provide an imaging lens group, an imaging device and an electronic device. The imaging lens group is equipped with four lenses with refractive power, the first lens is designed with positive refractive power, and its object-side surface It is convex, so it can effectively control the volume of the imaging lens group and improve the convenience of carrying. In addition, the object-side surface of the second lens of the imaging lens group is designed as a concave surface, which can effectively balance the aberration generated by the first lens.

In order to achieve the above object, the present invention provides an imaging lens group, which sequentially includes a first lens, a second lens, a third lens and a fourth lens from the object side to the image side, the first lens has positive refractive power, and the object The lateral surface is convex near the axis. The second lens has negative refractive power, and its object-side surface is concave near the axis. The third lens has positive refractive power, and its object-side surface and image-side surface are both aspherical. The fourth lens has refractive power, and its object-side surface and image-side surface are both aspherical. The imaging lens group also includes an aperture, and there is no lens with refractive power between the aperture and the first lens. There are four lenses with refractive power in the imaging lens group. The radius of curvature of the second lens object side surface is R3, the radius of curvature of the second lens image side surface is R4, the focal length of the imaging lens group is f, and the maximum image height of the imaging lens group is ImgH, the first lens and the second lens at The distance on the optical axis is T12, the distance between the second lens and the third lens on the optical axis is T23, and the thickness of the second lens on the optical axis is CT2, which meets the following conditions:

(R3+R4)/(R3-R4)<0.0;

2.4<f/ImgH<6.5;

-4.0<R3/T23<0.0; and

0.3<T12/CT2<5.0.

In order to better achieve the above object, the present invention also provides an imaging lens group, which sequentially includes a first lens, a second lens, a third lens and a fourth lens from the object side to the image side. The first lens has positive refractive power, and its object-side surface is convex near the axis. The second lens has negative refractive power, and its object-side surface is concave near the axis. The third lens has positive refractive power, and its object-side surface and image-side surface are both aspherical. The fourth lens has negative refractive power, and its object-side surface and image-side surface are both aspherical. The imaging lens group also includes an aperture, and there is no lens with refractive power between the aperture and the first lens. There are four lenses with refractive power in the imaging lens group, and there is an air gap between any two adjacent lenses with refractive power. The radius of curvature of the object-side surface of the first lens is R1, the radius of curvature of the image-side surface of the first lens is R2, the curvature radius of the object-side surface of the second lens is R3, and the curvature radius of the image-side surface of the second lens is R4. The focal length of the group is f, the maximum image height of the imaging lens group is 1 mgH, and the thickness of the first lens on the optical axis is CT1, which satisfies the following conditions:

(R3+R4)/(R3-R4)<0.0;

2.4<f/ImgH<6.5;

-0.50<R1/R2<0.50; and

3.0<(f/R1)-(f/R2)+((f*CT1)/(R1*R2))<7.5.

In order to better achieve the above object, the present invention also provides an image capturing device, comprising the above-mentioned imaging lens group and an electronic photosensitive element.

In order to better achieve the above object, the present invention also provides an electronic device, which includes the above image capturing device.

Technical effect of the present invention is:

In the imaging lens group, imaging device and electronic device of the present invention, the imaging lens group is equipped with four lenses with refractive power, the first lens is designed with positive refractive power, and its object side surface is convex, so the imaging lens can be effectively controlled. The size of the lens group improves the convenience of carrying. In addition, the object-side surface of the second lens of the imaging lens group is designed as a concave surface, which can effectively balance the aberration generated by the first lens.

The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments, but not as a limitation of the present invention.

Description of drawings

Fig. 1 is the schematic diagram of a kind of imaging device of the first embodiment of the present invention;

2A-2C are the spherical aberration, astigmatism and distortion curves of the first embodiment in order from left to right;

FIG. 3 is a schematic diagram of an imaging device according to a second embodiment of the present invention;

4A-4C are the spherical aberration, astigmatism and distortion curves of the second embodiment in order from left to right;

FIG. 5 is a schematic diagram of an imaging device according to a third embodiment of the present invention;

6A-6C are the spherical aberration, astigmatism and distortion curves of the third embodiment in order from left to right;

FIG. 7 is a schematic diagram of an imaging device according to a fourth embodiment of the present invention;

8A-8C are the spherical aberration, astigmatism and distortion curves of the fourth embodiment in order from left to right;

FIG. 9 is a schematic diagram of an imaging device according to a fifth embodiment of the present invention;

10A-10C are the spherical aberration, astigmatism and distortion curves of the fifth embodiment in order from left to right;

Fig. 11 is a schematic diagram of an imaging device according to the sixth embodiment of the present invention;

12A-12C are the spherical aberration, astigmatism and distortion curves of the sixth embodiment in order from left to right;

Fig. 13 is a schematic diagram of an imaging device according to the seventh embodiment of the present invention;

14A-14C are the spherical aberration, astigmatism and distortion curves of the seventh embodiment in order from left to right;

Fig. 15 is a schematic diagram of an imaging device according to the eighth embodiment of the present invention;

16A-16C are the spherical aberration, astigmatism and distortion curves of the eighth embodiment from left to right;

Fig. 17 is a schematic diagram of an imaging device according to the ninth embodiment of the present invention;

18A-18C are the spherical aberration, astigmatism and distortion curves of the ninth embodiment in order from left to right;

Fig. 19 is a schematic diagram of an imaging device according to the tenth embodiment of the present invention;

Fig. 20 is a schematic diagram of an imaging device according to an eleventh embodiment of the present invention;

FIG. 21 is a schematic diagram of an electronic device according to a twelfth embodiment of the present invention;

FIG. 22 is a schematic diagram of an electronic device according to a thirteenth embodiment of the present invention;

FIG. 23 is a schematic diagram of an electronic device according to a fourteenth embodiment of the present invention.

Among them, reference signs

Aperture 100, 200, 300, 400, 500, 600, 700, 800, 900

First lens 110, 210, 310, 410, 510, 610, 710, 810, 910

Object side surface 111, 211, 311, 411, 511, 611, 711, 811, 911

Image side surface 112, 212, 312, 412, 512, 612, 712, 812, 912

Second lens 120, 220, 320, 420, 520, 620, 720, 820, 920

Object side surface 121, 221, 321, 421, 521, 621, 721, 821, 921

Image side surface 122, 222, 322, 422, 522, 622, 722, 822, 922

Third lens 130, 230, 330, 430, 530, 630, 730, 830, 930

Object side surface 131, 231, 331, 431, 531, 631, 731, 831, 931

Image side surface 132, 232, 332, 432, 532, 632, 732, 832, 932

Fourth lens 140, 240, 340, 440, 540, 640, 740, 840, 940

Object side surface 141, 241, 341, 441, 541, 641, 741, 841, 941

Image side surface 142, 242, 342, 442, 542, 642, 742, 842, 942

IR Cut Filters 150, 250, 350, 450, 550, 650, 750, 850, 950

Image plane 160, 260, 360, 460, 560, 660, 760, 860, 960

Electronic photosensitive element 170, 270, 370, 470, 570, 670, 770, 870, 970

20 subjects

21 Prisms

30, 32, 34 Electronics

31, 33, 35 Imaging device

CT1 The thickness of the first lens on the optical axis

CT2 The thickness of the second lens on the optical axis

CT3 The thickness of the third lens on the optical axis

Entrance pupil diameter of EPD imaging lens group

Fno aperture value

f The focal length of the imaging lens group

f1 focal length of the first lens

f2 focal length of the second lens

f3 focal length of the third lens

f4 Focal length of the fourth lens

Half of the maximum viewing angle of the HFOV imaging lens group

ImgH The maximum image height of the imaging lens group

Nmax The largest of the refractive indices of the first lens, the second lens, the third lens, and the fourth lens

R1 The radius of curvature of the object-side surface of the first lens

R2 The radius of curvature of the image side surface of the first lens

R3 The radius of curvature of the object-side surface of the second lens

R4 The radius of curvature of the image-side surface of the second lens

Distance from the SD aperture to the image side surface of the fourth lens on the optical axis

TD The distance from the object-side surface of the first lens to the image-side surface of the fourth lens on the optical axis

TL is the distance from the object-side surface of the first lens to the imaging plane on the optical axis

T12 The distance between the first lens and the second lens on the optical axis

T23 Distance between the second lens and the third lens on the optical axis

T34 Distance between the third lens and the fourth lens on the optical axis

V2 Dispersion coefficient of the second lens

Dispersion coefficient of V3 third lens

Y11 Effective radius of the object side surface of the first lens

Y42 Effective radius of the image side surface of the fourth lens

Detailed ways

Below in conjunction with accompanying drawing, structural principle and working principle of the present invention are specifically described:

The invention provides an imaging lens group, which sequentially includes a first lens, a second lens, a third lens, a fourth lens and an aperture from the object side to the image side. The imaging lens group has four lenses with refractive power, and at least one surface of the second lens or the third lens or the fourth lens may have at least one inflection point to correct off-axis aberrations.

The first lens has positive refractive power, and its object-side surface is convex near the axis. Thereby, the volume of the imaging lens group can be effectively controlled, and the convenience of carrying is improved.

The second lens has negative refractive power, and its object-side surface is concave near the axis. Thereby, the aberration generated by the first lens can be effectively balanced. The object-side surface of the second lens may have at least one convex surface off-axis, and the image-side surface of the second lens may have a convex surface near the axis, so as to correct system astigmatism.

The third lens has positive refractive power, and its object-side surface can be convex or concave near the axis, so as to cooperate with the configuration of the overall optical system and further correct system aberrations, and its object-side surface and image-side surface are both aspherical.

The fourth lens can have negative refractive power, and its object-side surface can be concave or convex near the axis. The image-side surface of the fourth lens can be concave near the axis, and the image-side surface has at least one convex surface off-axis, and both the object-side surface and the image-side surface of the fourth lens are aspherical. Thereby, aberrations can be corrected advantageously.

In the imaging lens group of the present invention, among the first lens to the fourth lens, the maximum distance between any two adjacent lenses on the optical axis may be between the second lens and the third lens, or may be between Between the third lens and the fourth lens.

The imaging lens group of the present invention is further provided with an aperture, and there is no lens with refractive power between the aperture and the first lens; the setting of the aperture can provide enough incident light for the optical system to improve image quality.

In the imaging lens set of the present invention, there is an air space between any two adjacent lenses with refractive power; in other words, the first lens to the fourth lens are four independent and non-cemented lenses. Because the process of cemented lenses is more complicated than that of non-cemented lenses, especially the cemented surfaces of the two lenses need to have high-precision curved surfaces in order to achieve high adhesion when the two lenses are bonded, and in the process of bonding, it may also be caused by Misalignment causes poor fit and affects optical imaging quality. Therefore, in the imaging lens set of the present invention, there is an air space between any two adjacent lenses with refractive power, which can eliminate the problems caused by cemented lenses.

The radius of curvature of the object-side surface of the second lens is R3, and the curvature radius of the image-side surface of the second lens is R4, which satisfy the following condition: (R3+R4)/(R3-R4)<0.0. In this way, the curvature of the image-side surface of the second lens is prevented from being too large, resulting in too high sensitivity and a decrease in yield.

The focal length of the imaging lens group is f, and the maximum image height of the imaging lens group is ImgH, which meets the following conditions: 2.4<f/ImgH<6.5. In this way, the imaging range can be effectively suppressed, so that the imaging quality of the partial image has a higher resolution. Preferably, the following condition is satisfied: 2.7<f/ImgH<5.0.

The radius of curvature of the object-side surface of the second lens is R3, and the distance between the second lens and the third lens on the optical axis is T23, which satisfies the following condition: -4.0<R3/T23<0.0. Thereby, the principal point of the second lens can be ensured to be close to the object-side end, and at the same time, the optical path reconciliation function between the second lens and the third lens can be satisfied.

The distance between the first lens and the second lens on the optical axis is T12, and the thickness of the second lens on the optical axis is CT2, which satisfies the following condition: 0.3<T12/CT2<5.0. Thereby, it is ensured that there is enough space between the first lens and the second lens to facilitate the assembly of the imaging lens group. Preferably, the following condition can be satisfied: 0.4< T12/CT2<3.0.

The radius of curvature of the object-side surface of the first lens is R1, and the curvature radius of the image-side surface of the first lens is R2, which satisfy the following condition: -0.50<R1/R2<0.50. Thereby, moving the principal point of the first lens toward the object-side end helps to shorten the back focal length of the imaging lens group and reduce the overall length of the imaging lens group. Preferably, the following condition is satisfied: -0.30<R1/R2<0.30.

The focal length of the imaging lens group is f, the radius of curvature of the object-side surface of the first lens is R1, the curvature radius of the image-side surface of the first lens is R2, and the thickness of the first lens on the optical axis is CT1, which satisfies the following conditions: 3.0 <(f/R1)-(f/R2)+((f*CT1)/(R1*R2))<7.5. In this way, the converging capability of the overall system can be concentrated on the object-side end of the imaging lens group, and a good telephoto function can be provided, making it more suitable for achieving telephoto requirements.

The radius of curvature of the object-side surface of the second lens is R3, and the radius of curvature of the image-side surface of the second lens is R4, which satisfy the following condition: |R3|<|R4|, which can provide good lens manufacturability.

Each of the first to fourth lenses has a refractive index, and a maximum value among these refractive indices of the first to fourth lenses is Nmax, which satisfies the following condition: 1.50<Nmax<1.70. Thereby, the configuration of the refractive power of the imaging lens group can be effectively balanced to reduce generation of aberrations.

The focal length of the imaging lens group is f, and the curvature radius of the object-side surface of the first lens is R1, which satisfies the following condition: 3.3<f/R1<8.5. Thereby, it is helpful to provide more suitable first lens refractive power.

The focal length of the imaging lens group is f, and the distance from the object-side surface of the first lens to the imaging plane is TL, which satisfies the following condition: 0.95<f/TL<1.5. Thereby, it is helpful to control the overall length of the imaging lens group and maintain its miniaturization.

The focal length of the imaging lens group is f, which satisfies the following condition: 5.5mm<f<12.0mm. Thereby, the focal length of the imaging lens group can be effectively controlled.

The focal length of the imaging lens group is f, the focal length of the first lens is f1, the focal length of the second lens is f2, the focal length of the third lens is f3, and the focal length of the fourth lens is f4, which meets the following conditions: 5.0<|f/ f1|+|f/f2|+|f/f3|+|f/f4|. Thereby, it is helpful for the imaging lens group to provide sufficient resolution.

The sum of the thicknesses of the first lens, the second lens, the third lens and the fourth lens on the optical axis is ΣCT, and the distance from the object-side surface of the first lens to the image-side surface of the fourth lens on the optical axis is TD, which satisfies the following Condition: ΣCT/TD<0.55. Thereby, proper configuration of each lens can effectively maintain the miniaturization of the imaging lens group.

The distance from the aperture to the image-side surface of the fourth lens on the optical axis is SD, and the distance from the object-side surface of the first lens to the image-side surface of the fourth lens on the optical axis is TD, which satisfies the following conditions: 0.65<SD/TD< 1.0. Thereby, it is beneficial to balance the telecentric effect and field angle of the imaging lens group.

The maximum entrance pupil diameter of the imaging lens group is EPD, and the maximum image height of the imaging lens group is ImgH, which meets the following conditions: 0.9<EPD/ImgH<2.0. In this way, the amount of light collected per unit area of the image can be increased to improve the imaging quality.

Half of the maximum viewing angle of the imaging lens group is HFOV, which satisfies the following condition: 0.20<tan(2*HFOV)<0.90. Thereby, it can ensure that the imaging lens group has a sufficient field of view.

The dispersion coefficient of the second lens is V2, and the dispersion coefficient of the third lens is V3, which satisfy the following condition: 20<V2+V3<60. Thereby, the system configuration can be balanced to help correct the aberration of small viewing angles.

The distance on the optical axis from the object-side surface of the first lens to the imaging plane is TL, which satisfies the following condition: TL <10.0mm. Thereby, the total length of the imaging lens group can be effectively controlled to maintain its miniaturization.

The distance between the first lens and the second lens on the optical axis is T12, the distance between the second lens and the third lens on the optical axis is T23, and the distance between the third lens and the fourth lens on the optical axis is T34, which satisfies The following conditions: 0<T12/(T23+T34)<0.60. Thereby, the distance on the optical axis between the first lens and the second lens can be effectively controlled, and better imaging quality can be provided for distant shooting.

The thickness of the first lens on the optical axis is CT1, and the thickness of the second lens on the optical axis is CT2, which satisfy the following condition: 1.7<CT1/CT2<8.0. Thereby, it can help to control the configuration of the system's refractive force, and then correct the system aberration.

The distance from the object-side surface of the first lens to the imaging surface is TL, and the maximum image height of the imaging lens group is ImgH, which satisfies the following conditions: 2.5<TL/ImgH<4.0. Thereby, the miniaturization can be maintained, so as to be mounted on a light and thin miniaturized electronic device.

The effective radius of the object-side surface of the first lens is Y11, and the effective radius of the image-side surface of the fourth lens is Y42, which satisfy the following condition: 0.7<Y11/Y42<1.8. In this way, the incident angle of light can be effectively suppressed, and the imaging quality can be further improved.

The distance between the second lens and the third lens on the optical axis is T23, the distance between the third lens and the fourth lens on the optical axis is T34, and the distance between the third lens and the optical axis is CT3, which meets the following conditions: 2.50 < (T23+T34)/CT3. In this way, the configuration of the third lens can be effectively adjusted to further correct the spherical aberration of the system.

According to the above-mentioned implementation manners, specific embodiments are proposed below and described in detail with reference to the drawings.

first embodiment

Please refer to Fig. 1 and Fig. 2, wherein Fig. 1 is a schematic diagram of an imaging device according to the first embodiment of the present invention, and Fig. 2A-2C are sequentially from left to right the spherical aberration, astigmatism and distortion of the first embodiment Graph. As can be seen from FIG. 1 , the imaging device of the first embodiment includes an imaging lens group (not otherwise labeled) and an electronic photosensitive element 170 . The imaging lens group includes a first lens 110, an aperture 100, a second lens 120, a third lens 130, a fourth lens 140, an infrared filter 150 and an imaging surface 160 from the object side to the image side, and the electronic photosensitive element 170 is disposed on the imaging surface 160 of the imaging lens group. The imaging lens group has four lenses with refractive power (110-140), and there is an air gap between any two adjacent lenses with refractive power.

The first lens 110 has a positive refractive power and is made of plastic material. The object-side surface 111 is convex near the axis, and the image-side surface 112 is convex near the axis. Both are aspherical.

The second lens 120 has negative refractive power and is made of plastic material. The object-side surface 121 is concave near the axis, and the image-side surface 122 is convex near the axis. Both are aspherical. The off-axis portion of the object-side surface 121 of the second lens 120 has a convex surface.

The third lens 130 has positive refractive power and is made of plastic material. The object-side surface 131 is convex near the axis, and the image-side surface 132 is convex near the axis. Both are aspherical. In the imaging lens set of the first embodiment, the maximum distance between any two adjacent lenses on the optical axis is between the second lens 120 and the third lens 130 .

The fourth lens 140 has negative refractive power and is made of plastic material. The object-side surface 141 is concave near the axis, and the image-side surface 142 is concave near the axis. Both are aspherical. The image-side surface 142 of the fourth lens 140 has at least one convex surface off-axis.

The infrared filtering filter 150 is made of glass, which is disposed between the fourth lens 140 and the imaging surface 160 and does not affect the focal length of the imaging lens group.

The curve equations of the aspheric surfaces of the above-mentioned lenses are expressed as follows:

;in:

X: The point on the aspheric surface whose distance from the optical axis is Y, and its relative distance from the intersection point tangent to the aspheric optical axis;

Y: The vertical distance between the point on the aspheric curve and the optical axis;

R: radius of curvature;

k: cone coefficient; and

Ai: i-th order aspheric coefficient.

In the imaging lens group of the first embodiment, the focal length of the imaging lens group is f, the aperture value (f-number) of the imaging lens group is Fno, and half of the maximum viewing angle (or called half viewing angle) of the imaging lens group is HFOV, which The values are as follows: f=7.31 mm, Fno=2.70, HFOV=16.0 degrees.

In the imaging lens group of the first embodiment, each of the first lens 110 to the fourth lens 140 has a refractive index, and the maximum value of these refractive indices of the first lens 110 to the fourth lens 140 is Nmax, which satisfies the following conditions: Nmax = 1.639.

In the imaging lens group of the first embodiment, the dispersion coefficient of the second lens 120 is V2, and the dispersion coefficient of the third lens 130 is V3, which satisfy the following condition: V2+V3=47.0.

In the imaging lens group of the first embodiment, the thickness of the first lens 110 on the optical axis is CT1, and the thickness of the second lens 120 on the optical axis is CT2, which satisfy the following condition: CT1/CT2=4.64.

In the imaging lens group of the first embodiment, the distance between the first lens 110 and the second lens 120 on the optical axis is T12, and the thickness of the second lens 120 on the optical axis is CT2, which satisfies the following conditions: T12/CT2 = 1.77.

In the imaging lens group of the first embodiment, the distance between the first lens 110 and the second lens 120 on the optical axis is T12, the distance between the second lens 120 and the third lens 130 on the optical axis is T23, and the distance between the third lens 120 and the third lens 130 is T23. The distance between the lens 130 and the fourth lens 140 on the optical axis is T34, which satisfies the following condition: T12/(T23+T34)=0.21.

In the imaging lens group of the first embodiment, the distance between the second lens 120 and the third lens 130 on the optical axis is T23, the distance between the third lens 130 and the fourth lens 140 on the optical axis is T34, and the distance between the third lens 130 and the fourth lens 140 on the optical axis is T34. The thickness of the lens 130 on the optical axis is CT3, which satisfies the following condition: (T23+T34)/CT3=2.93.

In the imaging lens group of the first embodiment, the radius of curvature of the object-side surface 111 of the first lens 110 is R1, and the radius of curvature of the image-side surface 112 of the first lens 110 is R2, which satisfies the following conditions: R1/R2=- 0.22.

In the imaging lens group of the first embodiment, the radius of curvature of the object-side surface 121 of the second lens 120 is R3, and the distance between the second lens 120 and the third lens 130 on the optical axis is T23, which satisfies the following conditions: R3/ T23=-1.04.

In the imaging lens group of the first embodiment, the focal length of the imaging lens group is f, and the curvature radius of the object-side surface 111 of the first lens 110 is R1, which satisfies the following condition: f/R1=3.69.

In the imaging lens group of the first embodiment, the radius of curvature of the object-side surface 121 of the second lens 120 is R3, and the radius of curvature of the image-side surface 122 of the second lens 120 is R4, which satisfies the following conditions: (R3+R4)/( R3-R4) = -1.10.

In the imaging lens group of the first embodiment, the focal length of the imaging lens group is f, the focal length of the first lens 110 is f1, the focal length of the second lens 120 is f2, the focal length of the third lens 130 is f3, and the focal length of the fourth lens 140 is The focal length is f4, which satisfies the following condition: |f/f1|+|f/f2|+|f/f3|+|f/f4|=7.29.

In the imaging lens group of the first embodiment, the focal length of the imaging lens group is f, the curvature radius of the object-side surface 111 of the first lens 110 is R1, the curvature radius of the image-side surface 112 of the first lens 110 is R2, and the first The thickness of the lens 110 on the optical axis is CT1, which satisfies the following condition: (f/R1)−(f/R2)+((f*CT1)/(R1*R2))=4.30.

In the imaging lens group of the first embodiment, the sum of the thicknesses of the first lens 110, the second lens 120, the third lens 130, and the fourth lens 140 on the optical axis is ΣCT, and the object-side surface 111 of the first lens 110 to The distance from the image-side surface 142 of the fourth lens 140 on the optical axis is TD, which satisfies the following condition: ΣCT/TD=0.48.

In the imaging lens group of the first embodiment, the effective radius of the object-side surface 111 of the first lens 110 is Y11, and the effective radius of the image-side surface 142 of the fourth lens 140 is Y42, which satisfies the following conditions: Y11/Y42=0.91 .

In the imaging lens group of the first embodiment, half of the maximum viewing angle of the imaging lens group is HFOV, which satisfies the following condition: tan(2*HFOV)=0.62.

In the imaging lens group of the first embodiment, the distance from the aperture 100 to the image-side surface 142 of the fourth lens 140 on the optical axis is SD, and the distance from the object-side surface 111 of the first lens 110 to the image-side surface 142 of the fourth lens 140 is on the optical axis The distance on is TD, which satisfies the following condition: SD/TD=0.74.

In the imaging lens group of the first embodiment, the maximum entrance pupil diameter of the imaging lens group is EPD, and the maximum image height of the imaging lens group is ImgH, which satisfies the following condition: EPD/ImgH=1.23.

In the imaging lens group of the first embodiment, the distance on the optical axis from the object-side surface 111 of the first lens 110 to the imaging surface 160 is TL, which satisfies the following condition: TL=7.00 mm.

In the imaging lens group of the first embodiment, the focal length of the imaging lens group is f, and the distance on the optical axis from the object-side surface 111 of the first lens 110 to the imaging surface 160 is TL, which satisfies the following condition: f/TL=1.05.

In the imaging lens group of the first embodiment, the focal length of the imaging lens group is f, and the maximum image height of the imaging lens group is ImgH, which satisfies the following condition: f/ImgH=3.32.

In the imaging lens group of the first embodiment, the distance on the optical axis from the object-side surface 111 of the first lens 110 to the imaging surface 160 is TL, which satisfies the following condition: TL/ImgH=3.17.

Then refer to Table 1 and Table 2 below.

Table 1 shows the detailed structural data of the first embodiment in FIG. 1 , where the units of the radius of curvature, thickness and focal length are mm, and surfaces 0-12 represent surfaces from the object side to the image side in sequence. Table 2 shows the aspheric surface data in the first embodiment, wherein k represents the cone coefficient in the aspheric curve equation, and A4-A14 represent the 4th-14th order aspheric coefficients of each surface. In addition, the tables of the following embodiments are the schematic diagrams and aberration curve diagrams corresponding to the respective embodiments, and the definitions of the data in the tables are the same as those in Table 1 and Table 2 of the first embodiment, and will not be repeated here.

second embodiment

Please refer to Fig. 3 and Fig. 4, wherein Fig. 3 is a schematic diagram of an imaging device according to the second embodiment of the present invention, and Fig. 4A-4C are sequentially from left to right the spherical aberration, astigmatism and distortion of the second embodiment Graph. It can be seen from FIG. 3 that the image capturing device of the second embodiment includes an imaging lens group (not another number) and an electronic photosensitive element 270 . The imaging lens group includes a first lens 210, an aperture 200, a second lens 220, a third lens 230, a fourth lens 240, an infrared filter 250, an imaging surface 260, and an electronic photosensitive element from the object side to the image side. 270 is disposed on the imaging surface 260 of the imaging lens group; wherein, there are four lenses with refractive power in the imaging lens group (210-240), and there is an air gap between any two adjacent lenses with refractive power.

The first lens 210 has a positive refractive power and is made of plastic material. The object-side surface 211 is convex near the axis, and the image-side surface 212 is convex near the axis. Both are aspherical.

The second lens 220 has negative refractive power and is made of plastic material. The object-side surface 221 is concave near the axis, and the image-side surface 222 is convex near the axis. Both are aspherical. The off-axis of the object-side surface 221 of the second lens 220 has at least one convex surface.

The third lens 230 has a positive refractive power and is made of plastic material. The object-side surface 231 is concave near the axis, and the image-side surface 232 is convex near the axis. Both of them are aspherical. In the imaging lens set of the second embodiment, the maximum distance between any two adjacent lenses on the optical axis is between the second lens 220 and the third lens 230 .

The fourth lens 240 has negative refractive power and is made of plastic material. The object-side surface 241 is convex near the axis, and the image-side surface 242 is concave near the axis. Both are aspherical. The image-side surface 242 of the fourth lens 240 has at least one convex surface off-axis.

The infrared filtering filter 250 is made of glass, which is disposed between the fourth lens 240 and the imaging surface 260 and does not affect the focal length of the imaging lens group.

Please refer to Table 3 and Table 4 below.

In the second embodiment, the curve equation of the aspheric surface is expressed in the form of the first embodiment. In addition, the definitions of the parameters in the table below are the same as those in the first embodiment, and will not be repeated here.

Cooperating with Table 3 and Table 4, the following data can be deduced:

third embodiment

Please refer to Fig. 5 and Fig. 6, wherein Fig. 5 is a schematic diagram of an imaging device according to the third embodiment of the present invention, and Fig. 6A-6C are sequentially from left to right the spherical aberration, astigmatism and distortion of the third embodiment Graph. As can be seen from FIG. 5 , the imaging device of the third embodiment includes an imaging lens group (not labeled separately) and an electronic photosensitive element 370 . The imaging lens group includes a first lens 310, an aperture 300, a second lens 320, a third lens 330, a fourth lens 340, an infrared filter 350, and an imaging surface 360 in order from the object side to the image side, and the electronic photosensitive element 370 is disposed on the imaging surface 360; wherein, there are four lenses with refractive power in the imaging lens group (310-340), and there is an air gap between any two adjacent lenses with refractive power.

The first lens 310 has a positive refractive power and is made of plastic material. The object-side surface 311 is convex near the axis, and the image-side surface 312 is convex near the axis. Both are aspherical.

The second lens 320 has a negative refractive power and is made of plastic material. The object-side surface 321 is concave near the axis, and the image-side surface 322 is convex near the axis, both of which are aspherical. The object-side surface 321 of the second lens 320 has at least one convex surface near the axis.

The third lens 330 has positive refractive power and is made of plastic material. The object-side surface 331 is convex near the axis, and the image-side surface 332 is concave near the axis. Both of them are aspherical.

The fourth lens 340 has a negative refractive power and is made of plastic material. The object-side surface 341 is convex near the axis, and the image-side surface 342 is concave near the axis. Both are aspherical. The image-side surface 342 of the fourth lens 340 has at least one convex surface off-axis, and in the imaging lens group of the third embodiment, the maximum distance between any two adjacent lenses on the optical axis is between the third lens 330 and the fourth lens 340 .

The infrared filter 350 is made of glass, and is disposed between the fourth lens 340 and the imaging surface 360 without affecting the focal length of the imaging lens group.

Please refer to Table 5 and Table 6 below.

In the third embodiment, the curve equation of the aspheric surface is expressed in the form of the first embodiment. In addition, the definitions of the parameters in the table below are the same as those in the first embodiment, and will not be repeated here.

Cooperating with Table 5 and Table 6, the following data can be deduced:

Fourth embodiment

Please refer to Fig. 7 and Fig. 8, wherein Fig. 7 is a schematic diagram of an imaging device according to the fourth embodiment of the present invention, and Fig. 8A-8C are sequentially from left to right the spherical aberration, astigmatism and distortion of the fourth embodiment Graph. It can be seen from FIG. 7 that the image capturing device of the fourth embodiment includes an imaging lens group (not another number) and an electronic photosensitive element 470 . The imaging lens group includes a first lens 410, an aperture 400, a second lens 420, a third lens 430, a fourth lens 440, an infrared filter 450, and an imaging surface 460 from the object side to the image side, and the electronic photosensitive element 470 is disposed on the imaging surface 460 of the imaging lens group; wherein, there are four lenses with refractive power in the imaging lens group (410-440), and there is an air gap between any two adjacent lenses with refractive power.

The first lens 410 has positive refractive power and is made of plastic material. The object-side surface 411 is convex off-axis, and the image-side surface 412 is convex off-axis, both of which are aspherical.

The second lens 420 has negative refractive power and is made of plastic material. The object-side surface 421 is concave off-axis, and the image-side surface 422 is concave off-axis, both of which are aspherical. The object-side surface 422 of the second lens 420 has at least one convex surface off-axis.

The third lens 430 has a positive refractive power and is made of plastic material. The object-side surface 431 is concave near the axis, and the image-side surface 432 is convex near the axis. Both are aspherical. In the imaging lens set of the fourth embodiment, the maximum distance between any two adjacent lenses on the optical axis is between the second lens 420 and the third lens 430 .

The fourth lens 440 has negative refractive power and is made of plastic material. The object-side surface 441 is concave near the axis, and the image-side surface 442 is concave near the axis. Both are aspherical. The image-side surface 442 of the fourth lens 440 has at least one convex surface off-axis.

The infrared filtering filter 450 is made of glass, which is disposed between the fourth lens 440 and the imaging surface 460 and does not affect the focal length of the imaging lens group.

Please refer to Table 7 and Table 8 below.

In the fourth embodiment, the curve equation of the aspheric surface is expressed in the form of the first embodiment. In addition, the definitions of the parameters in the table below are the same as those in the first embodiment, and will not be repeated here.

Cooperating with Table 7 and Table 8, the following data can be deduced:

fifth embodiment

Please refer to Fig. 9 and Fig. 10, wherein Fig. 9 is a schematic diagram of an imaging device according to the fifth embodiment of the present invention, and Fig. 10A-10C are sequentially from left to right the spherical aberration, astigmatism and distortion of the fifth embodiment Graph. As can be seen from FIG. 9 , the imaging device of the fifth embodiment includes an imaging lens group (not otherwise labeled) and an electronic photosensitive element 570 . The imaging lens group includes an aperture 500, a first lens 510, a second lens 520, a third lens 530, a fourth lens 540, an infrared filter 550 and an imaging surface 560 in order from the object side to the image side, and the electronic photosensitive element 570 is disposed on the imaging surface 560 of the imaging lens group; wherein, the imaging lens group has four lenses with refractive power (510-540), and there is an air gap between two adjacent lenses with refractive power.

The first lens 510 has positive refractive power and is made of plastic material. The object-side surface 511 is convex near the axis, and the image-side surface 512 is convex near the axis. Both are aspherical.

The second lens 520 has negative refractive power and is made of plastic material. The object-side surface 521 is concave near the axis, and the image-side surface 522 is concave near the axis. Both are aspherical. The object-side surface 521 of the second lens 520 has at least one convex surface off-axis.

The third lens 530 has positive refractive power and is made of plastic material. The object-side surface 531 is concave near the axis, and the image-side surface 532 is convex near the axis. Both of them are aspherical. In the imaging lens set of the fifth embodiment, the maximum distance between any two adjacent lenses on the optical axis is between the second lens 520 and the third lens 530 .

The fourth lens 540 has negative refractive power and is made of plastic material. The object-side surface 541 is concave near the axis, and the image-side surface 542 is concave near the axis. Both are aspherical. The off-axis of the fourth lens 540 has at least one convex surface.

The infrared filtering filter 550 is made of glass, which is disposed between the fourth lens 540 and the imaging surface 560 and does not affect the focal length of the imaging lens group.

Please refer to Table 9 and Table 10 below.

In the fifth embodiment, the curve equation of the aspheric surface is expressed in the form of the first embodiment. In addition, the definitions of the parameters in the table below are the same as those in the first embodiment, and will not be repeated here.

Cooperating with Table 9 and Table 10, the following data can be deduced:

Sixth embodiment

Please refer to Fig. 11 and Fig. 12, wherein Fig. 11 is a schematic diagram of the imaging device of the sixth embodiment of the present invention, and Fig. 12A-12C are the spherical aberration, aberration and distortion curves of the sixth embodiment in sequence from left to right . It can be seen from FIG. 11 that the image capturing device of the sixth embodiment includes an imaging lens group (not another number) and an electronic photosensitive element 670. The imaging lens group includes an aperture 600, a first lens 610, a second lens 620, a third lens 630, a fourth lens 640, an infrared filter 650, and an imaging surface 660 in order from the object side to the image side, and the electronic photosensitive element 670 is disposed on the imaging surface 660 of the imaging lens group; wherein, there are four lenses with refractive power in the imaging lens group (610-640), and there is an air gap between two adjacent lenses with refractive power.

The first lens 610 has a positive refractive power and is made of plastic material. The object-side surface 611 is convex near the axis, and the image-side surface 612 is convex near the axis. Both are aspherical.

The second lens 620 has a negative refractive power and is made of plastic material. The object-side surface 621 is concave near the axis, and the image-side surface 622 is concave near the axis. Both are aspherical. The object-side surface 621 of the second lens 620 has at least one convex surface off-axis.

The third lens 630 has positive refractive power and is made of plastic material. The object-side surface 631 is convex near the axis, and the image-side surface 632 is convex near the axis. Both are aspherical. In the imaging lens set of the sixth embodiment, the maximum distance between any two adjacent lenses on the optical axis is between the second lens 620 and the third lens 630 .

The fourth lens 640 has negative refractive power and is made of plastic material. The object-side surface 641 is concave near the axis, and the image-side surface 642 is convex near the axis. Both are aspherical.

The infrared filter 650 is made of glass, and is disposed between the fourth lens 640 and the imaging surface 660 without affecting the focal length of the imaging lens group.

Please refer to Table 11 and Table 12 below.

In the sixth embodiment, the curve equation of the aspheric surface is expressed in the form of the first embodiment. In addition, the definitions of the parameters in the table below are the same as those in the first embodiment, and will not be repeated here.

Cooperating with Table 11 and Table 12, the following data can be calculated:

Seventh embodiment

Please refer to Fig. 13 and Fig. 14, wherein Fig. 13 is a schematic diagram of an imaging device of the seventh embodiment of the present invention, and Fig. 14A-14C are sequentially from left to right the spherical aberration, astigmatism and distortion of the seventh embodiment Graph. As can be seen from FIG. 13 , the imaging device of the seventh embodiment includes an imaging lens group (not otherwise labeled) and an electronic photosensitive element 770 . The imaging lens group includes a first lens 710, an aperture 700, a second lens 720, a third lens 730, a fourth lens 740, an infrared filter 750, and an imaging surface 760 from the object side to the image side, and the electronic photosensitive element 770 is disposed on the imaging surface 760; wherein, there are four lenses with refractive power in the imaging lens group (710-740), and there is an air gap between two adjacent lenses with refractive power.

The first lens 710 has positive refractive power and is made of plastic material. The object-side surface 711 is convex near the axis, and the image-side surface 712 is concave near the axis. Both are aspherical.

The second lens 720 has a negative refractive power and is made of plastic material. The object-side surface 721 is concave near the axis, and the image-side surface 722 is convex near the axis, both of which are aspherical. The object-side surface of the second lens 720 has at least one convex surface off-axis.

The third lens 730 has positive refractive power and is made of plastic material. The object-side surface 731 is concave near the axis, and the image-side surface 732 is convex near the axis. Both are aspherical.

The fourth lens 740 has negative refractive power and is made of plastic material. The object-side surface 741 is concave near the axis, and the image-side surface 742 is concave near the axis, both of which are aspherical. The image-side surface 742 of the fourth lens 740 has at least one convex surface off-axis. In the imaging lens set of the seventh embodiment, the maximum distance between any two adjacent lenses on the optical axis is between the third lens 730 and the fourth lens 740 .

The infrared filter 750 is made of glass, which is disposed between the fourth lens 740 and the imaging surface 760 and does not affect the focal length of the imaging lens group.

Please refer to Table 13 and Table 14 below.

In the seventh embodiment, the curve equation of the aspheric surface is expressed in the form of the first embodiment. In addition, the definitions of the parameters in the table below are the same as those in the first embodiment, and will not be repeated here.

Cooperating with Table 13 and Table 14, the following data can be calculated:

Eighth embodiment

Please refer to Fig. 15 and Fig. 16, wherein Fig. 15 is a schematic diagram of an imaging device according to the eighth embodiment of the present invention, and Fig. 16A-16C are sequentially from left to right the spherical aberration, aberration or distortion of the eighth embodiment Graph. It can be seen from FIG. 15 that the image capturing device of the eighth embodiment includes an imaging lens group (not another number) and an electronic photosensitive element 870 . The imaging lens group includes an aperture 800, a first lens 810, a second lens 820, a third lens 830, a fourth lens 840, an infrared filter 850, and an imaging surface 860 in order from the object side to the measurement, and the electronic photosensitive element 870 is arranged on the imaging surface 860 of the imaging lens group; wherein, there are four lenses with refractive power in the imaging lens group (810-840), and there is an air gap between two adjacent lenses with refractive power.

The first lens 810 has positive refractive power and is made of plastic material. The object-side surface 811 is convex near the axis, and the image-side surface 812 is convex near the axis. Both are aspherical.

The second lens 820 has negative refractive power and is made of plastic material. The object-side surface 821 is concave near the axis, and the image-side surface 822 is convex near the axis. Both are aspherical. The object-side surface 821 of the second lens 820 has at least one convex surface off-axis.

The third lens 830 has positive refractive power and is made of plastic material. The object-side surface 831 is convex near the axis, and the image-side surface 832 is convex near the axis. Both are aspherical. In the imaging lens set of the eighth embodiment, the maximum distance between any two adjacent lenses on the optical axis is between the second lens 820 and the third lens 830 .

The fourth lens 840 has negative refractive power and is made of plastic material. The object-side surface 841 is convex near the axis, and the image-side surface 842 is concave near the axis. Both are aspherical. The image-side surface of the fourth lens 840 has a convex surface off-axis.

The infrared filter 850 is made of glass, and is disposed between the fourth lens 840 and the imaging surface 860 without affecting the focal length of the imaging lens group.

Then refer to Table 15 and Table 16 below.

In the eighth embodiment, the curve equation of the aspheric surface is expressed in the form of the first embodiment. In addition, the definitions of the parameters in the table below are the same as those in the first embodiment, and will not be repeated here.

Cooperating with Table 15 and Table 16, the following data can be calculated:

Ninth embodiment

Please refer to Fig. 17 and Fig. 18, wherein Fig. 17 is a schematic diagram of an imaging device of the ninth embodiment of the present invention, and Fig. 18A-18C are sequentially from left to right the spherical aberration, aberration and distortion of the ninth embodiment Graph. It can be seen from FIG. 17 that the image capturing device of the ninth embodiment includes an imaging lens group (not another number) and an electronic photosensitive element 970 . The imaging lens group includes a diaphragm 900, a first lens 910, a second lens 920, a third lens 930, a fourth lens 940, an infrared filter 950, and an imaging surface 960 in order from the object side to the image side, and the electronic photosensitive element 970 is arranged on the imaging surface 960 of the imaging lens group; wherein, there are four lenses with refractive power in the imaging lens group (910-940), and there is an air gap between any two adjacent lenses with refractive power.

The first lens 910 has positive refractive power and is made of plastic material. The object-side surface 911 is convex near the axis, and the image-side surface 912 is concave near the axis. Both are aspherical.

The second lens 920 has negative refractive power and is made of plastic material. The object-side surface 921 is concave near the axis, and the image-side surface 922 is convex near the axis. Both are aspherical. The object-side surface of the second lens 920 has a convex surface off-axis.

The third lens 930 has positive refractive power and is made of plastic material. The object-side surface 931 is convex near the axis, and the image-side surface 932 is convex near the axis. Both are aspherical. In the imaging lens set of the ninth embodiment, the maximum distance between any two adjacent lenses on the optical axis is between the second lens 920 and the third lens 930 .

The fourth lens 940 has negative refractive power and is made of plastic material. The object-side surface 941 is concave near the axis, and the image-side surface 942 is concave near the axis. Both are aspherical. The image-side surface of the fourth lens 940 has at least one convex surface off-axis.

The infrared filter 950 is made of glass, and is disposed between the fourth lens 940 and the imaging surface 960 without affecting the focal length of the imaging lens group.

Then refer to Table 17 and Table 18 below.

In the ninth embodiment, the curve equation of the aspheric surface is expressed in the form of the first embodiment. In addition, the definitions of the parameters in the table below are the same as those in the first embodiment, and will not be repeated here.

Cooperating with Table 17 and Table 18, the following data can be calculated:

Tenth embodiment

Please refer to FIG. 19 , which is a schematic diagram of an imaging device according to a tenth embodiment of the present invention. The imaging device of the tenth embodiment includes an imaging lens group (not otherwise labeled) and an electronic photosensitive element 170 according to the present invention. It should be particularly noted that in FIG. 19, the imaging lens group and the electronic photosensitive element are the imaging lens group and the electronic photosensitive element shown in the first embodiment as the description range, that is, the components of the imaging lens group shown in FIG. 19 The labels are the same as the imaging lens group of the first embodiment; however, in actual implementation, the imaging lens group and the electronic photosensitive element can also be any grouped imaging lens group and electronic photosensitive element in the second embodiment to the ninth embodiment .

The imaging lens group is disposed between the subject 20 and the electronic photosensitive element 170 , and the electronic photosensitive element 170 is disposed on the imaging surface 160 of the imaging lens group. The imaging lens group is used to image the image of the subject 20 on the electronic photosensitive element 170 disposed on the imaging surface 160 .

Eleventh embodiment

Please refer to FIG. 20 , which is a schematic diagram of an imaging device according to an eleventh embodiment of the present invention. The imaging device of the eleventh embodiment includes an imaging lens group (not another number), a prism 21 and an electronic photosensitive element 170 . It should be particularly noted that in FIG. 20, the imaging lens group and the electronic photosensitive element are the imaging lens group and the electronic photosensitive element shown in the first embodiment as the description range, that is, the imaging lens group and the electronic photosensitive element shown in FIG. The element label of the photosensitive element is the same as that of the imaging lens group and the electronic photosensitive element of the first embodiment; however, in actual implementation, the imaging lens group and the electronic photosensitive element can also be any group in the second embodiment to the ninth embodiment Imaging lens group and electronic photosensitive element.

The imaging lens group is arranged between the object 20 and the electronic photosensitive element 170, and the electronic photosensitive element 170 is arranged on the imaging surface 160 of the imaging lens group, and the prism 21 is arranged between the object 20 and the imaging lens group. The imaging lens group is used to image the object 20 on the electronic photosensitive element 170 located on the imaging surface 160, and the prism 21 is used to turn the optical path of the imaging device to reduce the height of the imaging device and make the spatial configuration more flexible. Mounted on thin electronic devices.

Twelfth embodiment

Please refer to FIG. 21 , which is a schematic diagram of an electronic device according to a twelfth embodiment of the present invention. The electronic device 30 of the twelfth embodiment is a smart phone, the electronic device 30 includes an imaging device 31, and the imaging device 31 includes an imaging lens group (not shown) and an electronic photosensitive element (not shown) according to the present invention, Wherein the electronic photosensitive element is arranged on the imaging surface of the imaging lens group.

Thirteenth embodiment

Please refer to FIG. 22 , which is a schematic diagram of an electronic device according to a thirteenth embodiment of the present invention. The electronic device 32 of the thirteenth embodiment is a tablet computer, and the electronic device 32 includes an image-taking device 33, and the image-taking device 33 includes an imaging lens group (not shown) and an electronic photosensitive element (not shown) according to the present invention, Wherein the electronic photosensitive element is arranged on the imaging surface of the imaging lens group.

Fourteenth embodiment

Please refer to FIG. 23 , which is a schematic diagram of an electronic device according to a fourteenth embodiment of the present invention. The electronic device 34 of the fourteenth embodiment is a head-mounted display device (Head-mounted display, HMD). The electronic device 34 includes an imaging device 35, and the imaging device 35 includes an imaging lens group (not shown in the figure) according to the present invention. ) and an electronic photosensitive element (not shown), the electronic photosensitive element is arranged on the imaging surface of the imaging lens group.

Certainly, the present invention also can have other multiple embodiments, without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and deformations according to the present invention, but these corresponding Changes and deformations should belong to the scope of protection of the appended claims of the present invention.

Claims (30)

1. a kind of imaging lens group, which is characterized in that include sequentially by object side to image side：

One first lens, it is convex surface to have positive refracting power, the paraxial place in object side surface；

One second lens, it is concave surface to have negative refracting power, the paraxial place in object side surface；

One the third lens have positive refracting power, and object side surface and image side surface are all aspherical；And

One the 4th lens have refracting power, and object side surface and image side surface are all aspherical；

Wherein, which further includes an aperture, without tool refracting power lens between the aperture and first lens；

Wherein, the lens of imaging lens group tool refracting power are four, and are had between two adjacent lens with refracting power The radius of curvature of one airspace, the first lens object side surface is R1, and the radius of curvature on the first lens image side surface is R2, The radius of curvature of the second lens object side surface is R3, and the radius of curvature on the second lens image side surface is R4, the imaging lens The focal length of group is f, and the maximum image height of the imaging lens group is ImgH, and first lens are with second lens in the interval on optical axis Distance is T12, which is T23 in the spacing distance on optical axis with the third lens, and first lens are on optical axis Thickness is CT1, which is CT2 in the thickness on optical axis, meets following condition：

(R3+R4)/(R3-R4)<0.0；

2.4<f/ImgH<6.5；

-4.0<R3/T23<0.0；

0.3<T12/CT2<5.0；

-0.50<R1/R2<0.50；And

3.0<(f/R1)-(f/R2)+((f*CT1)/(R1*R2))<7.5。

2. imaging lens group as described in claim 1, which is characterized in that the 4th lens have negative refracting power, the third saturating The paraxial place in mirror image side surface is convex surface.

3. imaging lens group as described in claim 1, which is characterized in that the 4th paraxial place in lens image side surface is concave surface, And the 4th lens image side surface off axis place have an at least convex surface.

4. imaging lens group as described in claim 1, which is characterized in that the paraxial place in the third lens object side surface is convex surface.

5. imaging lens group as described in claim 1, which is characterized in that the 4th paraxial place in lens object side surface is concave surface.

6. imaging lens group as described in claim 1, which is characterized in that the paraxial place in the second lens image side surface is convex surface.

7. imaging lens group as described in claim 1, which is characterized in that the radius of curvature of the second lens object side surface is R3, the radius of curvature on the second lens image side surface are R4, and first lens to the 4th lens respectively have a refractive index, this Maximum value in these refractive index of one lens to the 4th lens is Nmax, meets following condition：

|R3|<|R4|；And

1.50<Nmax<1.70。

8. imaging lens group as described in claim 1, which is characterized in that the focal length of the imaging lens group is f, first lens The radius of curvature of object side surface is R1, meets following condition：

3.3<f/R1<8.5。

9. imaging lens group as described in claim 1, which is characterized in that the focal length of the imaging lens group is f, first lens Object side surface is TL in the distance on optical axis to an imaging surface, meets following condition：

0.95<f/TL<1.5。

10. imaging lens group as described in claim 1, which is characterized in that the focal length of the imaging lens group is f, under meeting Row condition：

5.5mm<f<12.0mm。

11. imaging lens group as described in claim 1, which is characterized in that first lens to second lens are on optical axis Spacing distance be T12, second lens in the thickness on optical axis be CT2, meet following condition：

0.4<T12/CT2<3.0。

12. imaging lens group as described in claim 1, which is characterized in that the focal length of the imaging lens group be f, this first thoroughly The focal length of mirror is f1, and the focal length of second lens is f2, and the focal length of the third lens is f3, and the focal length of the 4th lens is f4, It meets following condition：

5.0<|f/f1|+|f/f2|+|f/f3|+|f/f4|。

13. imaging lens group as described in claim 1, which is characterized in that place has extremely off axis for the second lens object side surface A few convex surface, first lens, second lens, the third lens and the 4th lens are respectively at the summation of thickness on optical axis Σ CT, the first lens object side surface to the 4th lens image side surface are TD in the distance on optical axis, meet following condition：

ΣCT/TD<0.55。

14. imaging lens group as described in claim 1, which is characterized in that second lens or the third lens or the 4th It is in the distance on optical axis with an at least point of inflexion, the aperture to the 4th lens image side surface on an at least surface for lens SD, the first lens object side surface to the 4th lens image side surface are TD in the distance on optical axis, meet following condition：

0.65<SD/TD<1.0。

15. imaging lens group as described in claim 1, which is characterized in that a diameter of EPD of entrance pupil of the imaging lens group, The maximum image height of the imaging lens group is ImgH, meets following condition：

0.9<EPD/ImgH<2.0。

16. a kind of imaging lens group, which is characterized in that include sequentially by object side to image side：

One first lens, it is convex surface to have positive refracting power, the paraxial place in the first lens object side surface；

One second lens, it is concave surface to have negative refracting power, the paraxial place in the second lens object side surface；

One the third lens, it is aspherical to have positive refracting power, object side surface and image side surface；And

One the 4th lens, it is aspherical to have negative refracting power, object side surface and image side surface；

Wherein, which further includes an aperture, without tool refracting power lens between the aperture and first lens；

Wherein, the lens with refracting power are four in the imaging lens group, and between two adjacent lens with refracting power With an airspace, the radius of curvature of the first lens object side surface is R1, the radius of curvature on the first lens image side surface Radius of curvature for R2, the second lens object side surface is R3, and the radius of curvature on the second lens image side surface is R4, the imaging The focal length of lens group is f, and the maximum image height of the imaging lens group is ImgH, which is CT1 in the thickness on optical axis, Meet following condition：

(R3+R4)/(R3-R4)<0.0；

2.4<f/ImgH<6.5；

-0.50<R1/R2<0.50；And

3.0<(f/R1)-(f/R2)+((f*CT1)/(R1*R2))<7.5。

17. imaging lens group as claimed in claim 16, which is characterized in that the paraxial place in the third lens object side surface is recessed Face.

18. imaging lens group as claimed in claim 16, which is characterized in that the 4th paraxial place in lens object side surface is convex Face, the 4th paraxial place in lens image side surface are concave surface, and place has an at least convex surface off axis on the 4th lens image side surface.

19. imaging lens group as claimed in claim 16, which is characterized in that the half at the maximum visual angle of the imaging lens group is HFOV meets following condition：

0.20<tan(2*HFOV)<0.90。

20. imaging lens group as claimed in claim 16, which is characterized in that first lens, second lens, the third are saturating The material of mirror and the 4th lens is plastic cement, and the abbe number of second lens is V2, and the abbe number of the third lens is V3, It meets following condition：

20<V2+V3<60。

21. imaging lens group as claimed in claim 16, which is characterized in that the radius of curvature of the second lens object side surface is R3, the radius of curvature on the second lens image side surface are R4, the first lens object side surface a to imaging surface on optical axis away from From for TL, meet following condition：

|R3|<|R4|；And

TL<10.0mm。

22. imaging lens group as claimed in claim 16, which is characterized in that the focal length of the imaging lens group is f, the imaging lens The maximum image height of head group is ImgH, meets following condition：

2.7<f/ImgH<5.0。

23. imaging lens group as claimed in claim 16, which is characterized in that the radius of curvature of the first lens object side surface is R1, the radius of curvature R 2 on the first lens image side surface, first lens are in the spacing distance on optical axis with second lens T12, second lens are T23 in the spacing distance on optical axis with the third lens, and the third lens are with the 4th lens in light Spacing distance on axis is T34, meets following condition：

-0.30<R1/R2<0.30；And

0<T12/(T23+T34)<0.60。

24. imaging lens group as claimed in claim 16, which is characterized in that the focal length of the imaging lens group be f, this first thoroughly The radius of curvature of mirror object side surface is R1, which is CT1 in the thickness on optical axis, and second lens are in the thickness on optical axis Degree is CT2, meets following condition：

3.3<f/R1<8.5；And

1.7<CT1/CT2<8.0。

25. imaging lens group as claimed in claim 16, which is characterized in that at least the one of the third lens or the 4th lens It is TL, the imaging in the distance on optical axis to have an at least point of inflexion, the first lens object side surface a to imaging surface on surface The maximum image height of lens group is ImgH, meets following condition：

2.5<TL/ImgH<4.0。

26. imaging lens group as claimed in claim 16, which is characterized in that place has extremely off axis for the second lens object side surface The effective radius on a few convex surface, the first lens object side surface is Y11, and the effective radius on the 4th lens image side surface is Y42, It meets following condition：

0.7<Y11/Y42<1.8。

27. imaging lens group as claimed in claim 16, which is characterized in that in first lens between the 4th lens, appoint Between two adjacent lens in the largest interval distance on optical axis between the second lens and the third lens, second lens with should The third lens are T23 in the distance on optical axis, and the third lens and the 4th lens are T34 at a distance from optical axis, and the third is saturating Mirror is CT3 in the thickness on optical axis, meets following condition：

2.50<(T23+T34)/CT3。

28. imaging lens group as claimed in claim 16, which is characterized in that in first lens between the 4th lens, appoint Between two adjacent lens in the largest interval distance on optical axis between the third lens and the 4th lens.

29. a kind of image-taking device includes imaging lens group and an electronics photosensitive element described in claim 16.

30. a kind of electronic device includes the image-taking device described in claim the 29.