TWI603114B - Optical lens system - Google Patents

Description

Imaging lens set

The present invention relates to an imaging lens set, and more particularly to a miniaturized five-piece imaging lens set for use in electronic products.

The high-quality small photographic lens is the standard equipment of various mobile devices. With the advancement of semiconductor manufacturing, the pixel area on the electronic photosensitive element is getting smaller and smaller, which makes the camera lens need more detailed analysis. Force, in order to present a more detailed picture quality.

Conventional 3 to 4 small lenses, such as mobile phones, tablets, and other wearable electronic devices, such as US 7,564,635, US 7,920,340, can not display more detailed image quality; Small lenses may have better image quality. However, in large apertures, such as US 8,605,368, US 8,649,113, TW application numbers 102137030, 102121155, they are often accompanied by the sensitivity of manufacturing assembly, making mass production difficult and increasing. The cost of mass production. Or to reduce the assembly tolerance, the surrounding imaging quality must be sacrificed to blur or deform the surrounding image.

Therefore, the continuous development of a high-quality lens with high resolution and low manufacturing assembly tolerance is the motivation for the development of the present invention.

It is an object of the present invention to provide an imaging lens set, and more particularly to a five-piece imaging lens set having high image count, high resolution, low distortion and low manufacturing tolerance.

In order to achieve the foregoing objective, an imaging lens set according to the present invention comprises, in order from the object side to the image side, an aperture; a first lens having a positive refractive power, the object side surface being near The optical axis is a convex surface, and the image side surface is convex at the near optical axis, and at least one surface of the object side surface and the image side surface is aspherical; a second lens has a negative refractive power, and the object side surface is near the optical axis a convex surface, at least one surface of the object side surface and the image side surface is aspherical; a third lens having a refractive power, the image side surface having a concave surface at a near optical axis, and at least one surface of the object side surface and the image side surface a fourth lens having a positive refractive power, a concave surface of the object side surface near the optical axis, a convex surface of the image side surface near the optical axis, and at least one surface of the object side surface and the image side surface being aspherical; a fifth lens having a negative refractive power, wherein the object side surface is concave at a near optical axis, and the image side surface is concave at a near optical axis, and at least one surface of the object side surface and the image side surface is aspherical, and the object side thereof At least one surface of the surface and the image side surface has at least one inflection point; The composite focal length of the second lens, the third lens and the fourth lens is f234, and the focal length of the fifth lens is f5, and the following condition is satisfied: -1.8<f234/f5<-1.0. By proper configuration of the refractive power, it helps to reduce the occurrence of spherical aberration and astigmatism.

Preferably, the object side surface of the second lens has a convex surface at a near optical axis, and the image side surface has a concave surface at a near optical axis; the object side surface of the third lens has a convex surface and an image side surface near the optical axis The area is concave.

Preferably, the focal length of the first lens is f1, the focal length of the second lens is f2, and the following condition is satisfied: -0.75 < f1/f2 < -0.4. Thereby, the refractive power arrangement of the first lens and the second lens is suitable, which is advantageous for obtaining a wide angle of view (angle of view) and reducing excessive increase of system aberration.

Preferably, the focal length of the second lens is f2, the focal length of the fourth lens is f4, and the following condition is satisfied: -2.6 < f2 / f4 < -1.8. Thereby, it is advantageous to enhance the large viewing angle and large aperture characteristics of the imaging lens group, and the sensitivity thereof can be reduced, which is beneficial to the fabrication of each lens and improves the production yield.

Preferably, the focal length of the fourth lens is f4, the focal length of the fifth lens is f5, and the following condition is satisfied: -1.35 < f4 / f5 < -0.9. Thereby, the back focus of the imaging lens group can be effectively shortened and maintained Its miniaturization.

Preferably, the focal length of the first lens is f1, the focal length of the third lens is f3, and the following condition is satisfied: -0.1 < f1/f3 < 0.15. Thereby, the balance of the refractive power of the imaging lens group can be maintained, thereby achieving the best imaging effect.

Preferably, the focal length of the second lens is f2, the focal length of the fifth lens is f5, and the following condition is satisfied: 1.8 < f2 / f5 < 3.1. Thereby, it is possible to shorten the total length of the imaging lens group and maintain its miniaturization.

Preferably, the focal length of the first lens is f1, the focal length of the fourth lens is f4, and the following condition is satisfied: 0.9 < f1/f4 < 1.5. Thereby, the balance of the refractive power of the imaging lens group can be maintained, thereby achieving the best imaging effect.

Preferably, the focal length of the first lens is f1, the combined focal length of the second lens and the third lens is f23, and the following condition is satisfied: -0.7 < f1/f23 < -0.5. Thereby, the balance of the refractive power of the imaging lens group can be maintained, thereby achieving the best imaging effect.

Preferably, the combined focal length of the second lens and the third lens is f23, and the combined focal length of the fourth lens and the fifth lens is f45, and the following condition is satisfied: -0.35<f23/f45<-0.05. When f23/f45 satisfies the foregoing relationship, the imaging lens group can have a large picture angle, a high number of pictures, and a low lens height, and the resolution capability is significantly improved. Conversely, if the optical data value range is exceeded, It can cause problems in the performance of the imaging lens set, low resolution, and insufficient yield.

Preferably, the combined focal length of the first lens and the second lens is f12, and the combined focal length of the third lens and the fourth lens is f34, and the following condition is satisfied: 1.4<f12/f34<2.8. When f12/f34 satisfies the foregoing relationship, the imaging lens group can have a large picture angle, a high number of pictures, and a low lens height, and the resolution capability is remarkably improved. On the contrary, if the optical data value range is exceeded, It can cause problems in the performance of the imaging lens set, low resolution, and insufficient yield.

Preferably, the combined focal length of the third lens and the fourth lens is f34, and the focal length of the fifth lens is f5, and the following condition is satisfied: -1.4 < f34 / f5 < -0.9. When f34/f5 satisfies the foregoing relationship, the imaging lens group can have a large picture angle, a high number of pictures, and a low lens height, and the image resolution capability is remarkably improved. Conversely, if the optical data value range is exceeded, It can cause problems in the performance of the imaging lens set, low resolution, and insufficient yield.

Preferably, the focal length of the first lens is f1, the combined focal length of the second lens, the third lens and the fourth lens is f234, and the following condition is satisfied: 0.6 < f1/f234 < 1.5. By proper configuration of the refractive power, it helps to reduce the occurrence of spherical aberration and astigmatism.

Preferably, the combined focal length of the second lens and the third lens is f23, the focal length of the fourth lens is f4, and the following condition is satisfied: -2.3 < f23 / f4 < -1.5. Thereby, it is advantageous to enhance the large viewing angle and large aperture characteristics of the imaging lens group, and the sensitivity thereof can be reduced, which is beneficial to the fabrication of each lens and improves the production yield.

Preferably, the combined focal length of the first lens, the second lens and the third lens is f123, the focal length of the fourth lens is f4, and the following condition is satisfied: 1.6 < f123 / f4 < 2.7. By proper configuration of the refractive power, it helps to reduce the occurrence of spherical aberration and astigmatism.

Preferably, the combined focal length of the first lens, the second lens and the third lens is f123, and the combined focal length of the fourth lens and the fifth lens is f45, and the following condition is satisfied: 0.05 < f123 / f45 < 0.4. By proper configuration of the refractive power, it helps to reduce the occurrence of spherical aberration and astigmatism.

Preferably, the first lens has a dispersion coefficient of V1, the second lens has a dispersion coefficient of V2, and satisfies the following condition: 30<V1-V2<42. Thereby, the chromatic aberration of the imaging lens group can be corrected.

Preferably, the fourth lens has a dispersion coefficient of V4, and the third lens has a dispersion coefficient of V3 and satisfies the following condition: 30<V4-V3<42. Thereby, the chromatic aberration of the imaging lens group can be corrected.

Preferably, the overall focal length of the imaging lens group is f, the distance from the object side surface of the first lens to the imaging surface on the optical axis is TL, and the following condition is satisfied: 0.6 < f / TL < 0.95. By this, there may be It is advantageous for obtaining a wide angle of view (angle of view) and for facilitating the miniaturization of the imaging lens group for mounting on thin electronic products.

With regard to the techniques, means, and other effects of the present invention in order to achieve the above objects, three preferred embodiments are described in detail with reference to the drawings.

100, 200, 300‧ ‧ aperture

110, 210, 310‧‧‧ first lens

111, 211, 311‧‧‧ ‧ side surface

112, 212, 312‧‧‧ side surface

120, 220, 320‧‧‧ second lens

121, 221, 321‧‧‧ ‧ side surface

122, 222, 322‧‧‧ image side surface

130, 230, 330‧‧‧ third lens

131, 231, 331‧‧‧ ‧ side surface

132, 232, 332‧‧‧ image side surface

140, 240, 340‧ ‧ fourth lens

141, 241, 341‧‧‧ ‧ side surface

142, 242, 342‧‧‧ image side surface

150, 250, 350‧‧‧ fifth lens

151, 251, 351‧‧‧ ‧ side surface

152, 252, 352‧‧‧ side surface

170, 270, 370‧‧‧ Infrared filtering filter elements

180, 280, 380‧‧ ‧ imaging surface

190, 290, 390‧‧‧ optical axis

F‧‧‧focal length of the imaging lens set

Aperture value of Fno‧‧· imaging lens set

Maximum field of view in the FOV‧‧· imaging lens set

F1‧‧‧The focal length of the first lens

F2‧‧‧The focal length of the second lens

f3‧‧‧The focal length of the third lens

F4‧‧‧The focal length of the fourth lens

f5‧‧‧Focus of the fifth lens

F12‧‧‧Combined focal length of the first lens and the second lens

F23‧‧‧Combined focal length of the second lens and the third lens

F34‧‧‧Combined focal length of the third lens and the fourth lens

F45‧‧‧Combined focal length of the fourth lens and the fifth lens

F123‧‧‧Combined focal length of the first lens, the second lens and the third lens

f234‧‧‧Combined focal length of the second lens, the third lens and the fourth lens

V1‧‧‧Dispersion coefficient of the first lens

V2‧‧‧Dispersion coefficient of the second lens

V3‧‧‧Dispersion coefficient of the third lens

V4‧‧‧Dispersion coefficient of the fourth lens

TL‧‧‧The distance from the object side surface of the first lens to the imaging surface on the optical axis

Fig. 1A is a schematic view showing an image forming lens group of a first embodiment of the present invention.

Fig. 1B is a left-to-right sequence of spherical aberration, astigmatism, and distortion of the imaging lens group of the first embodiment.

Figure 2A is a schematic illustration of an imaging lens set of a second embodiment of the present invention.

2B is a spherical aberration, astigmatism, and distortion curve of the imaging lens group of the second embodiment, from left to right.

Figure 3A is a schematic illustration of an imaging lens set of a third embodiment of the present invention.

Fig. 3B is a spherical aberration, astigmatism, and distortion curve of the imaging lens group of the third embodiment, from left to right.

<First Embodiment>

1A and FIG. 1B, FIG. 1A is a schematic diagram of an imaging lens group according to a first embodiment of the present invention, and FIG. 1B is a left-to-right spherical aberration and astigmatism of the imaging lens group of the first embodiment. And the distortion curve. As shown in FIG. 1A, the imaging lens assembly includes an aperture 100 and an optical group. The optical group sequentially includes a first lens 110, a second lens 120, a third lens 130, and a fourth lens 140 from the object side to the image side. a fifth lens 150, an infrared filter element 170, and an imaging surface 180, wherein the imaging The lens with refractive power in the lens set is five pieces. The aperture 100 is disposed between the image side surface 112 of the first lens 110 and the subject.

The first lens 110 has a positive refractive power and is made of a plastic material. The object side surface 111 is convex at the near optical axis 190, and the image side surface 112 is convex at the near optical axis 190, and the object side surface 111 and the image side are Surface 112 is aspherical.

The second lens 120 has a negative refractive power and is made of a plastic material. The object side surface 121 is convex at the near optical axis 190, and the image side surface 122 is concave at the near optical axis 190, and the object side surface 121 and the image side are Surface 122 is aspherical.

The third lens 130 has a negative refractive power and is made of a plastic material. The object side surface 131 is convex at the near optical axis 190, and the image side surface 132 is concave at the near optical axis 190, and the object side surface 131 and the image side are The surfaces 132 are all aspherical.

The fourth lens 140 has a positive refractive power and is made of a plastic material. The object side surface 141 is concave at the near optical axis 190, and the image side surface 142 is convex at the near optical axis 190, and the object side surface 141 and the image side are Surfaces 142 are all aspherical.

The fifth lens 150 has a negative refractive power and is made of a plastic material, and the object side surface 151 is concave at the near optical axis 190, and the image side surface 152 is concave at the near optical axis 190, and the object side surface 151 and the image side are The surface 152 is aspherical, and at least one surface of the object side surface 151 and the image side surface 152 has at least one inflection point.

The infrared filter element 170 is made of glass and disposed between the fifth lens 150 and the imaging surface 180 without affecting the focal length of the imaging lens group.

The aspherical curve equations of the above lenses are expressed as follows:

Where z is the position value with reference to the surface apex at a position of height h in the direction of the optical axis 190; c is the curvature of the lens surface near the optical axis 190, and is the reciprocal of the radius of curvature (R) (c = 1/R) , R is transparent The mirror surface is close to the radius of curvature of the optical axis 190, h is the vertical distance of the lens surface from the optical axis 190, k is a conic constant, and A, B, C, D, E, G, ... It is a high-order aspheric coefficient.

In the imaging lens set 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 the maximum angle of view in the imaging lens group is FOV, and the values are as follows: f=3.710 (mm); Fno=2.0; and FOV=78 (degrees).

In the imaging lens set of the first embodiment, the first lens 110 is f1, the second lens 120 is f2, and the following condition is satisfied: f1/f2 = -0.5210.

In the imaging lens set of the first embodiment, the second lens 120 is f2, and the fourth lens 140 is f4 and satisfies the following condition: f2/f4 = -2.0249.

In the imaging lens group of the first embodiment, the fourth lens 140 is f4, and the fifth lens 150 is f5 and satisfies the following condition: f4/f5 = -1.1917.

In the imaging lens set of the first embodiment, the first lens 110 is f1, the third lens 130 is f3, and the following condition is satisfied: f1/f3 = -0.0860.

In the imaging lens group of the first embodiment, the second lens 120 is f2, and the fifth lens 150 is f5 and satisfies the following condition: f2/f5 = 2.4131.

In the imaging lens group of the first embodiment, the first lens 110 is f1, and the fourth lens 140 is f4, and the following condition is satisfied: f1/f4 = 1.0549.

In the imaging lens set of the first embodiment, the first lens 110 is f1, the combined focal length of the second lens 120 and the third lens 130 is f23, and the following condition is satisfied: f1/f23=-0.6159.

In the imaging lens set of the first embodiment, the combined focal length of the second lens 120 and the third lens 130 is f23, and the combined focal length of the fourth lens 140 and the fifth lens 150 is f45, and the following condition is satisfied: f23/f45 =-0.0622.

In the imaging lens set of the first embodiment, the composite focal length of the first lens 110 and the second lens 120 is f12, and the combined focal length of the third lens 130 and the fourth lens 140 is f34, and the following condition is satisfied: f12/f34 =1.6071.

In the imaging lens set of the first embodiment, the combined focal length of the third lens 130 and the fourth lens 140 is f34, the focal length of the fifth lens 150 is f5, and the following condition is satisfied: f34/f5=-1.2606.

In the imaging lens set of the first embodiment, the focal length of the first lens is f1, the combined focal length of the second lens 120, the third lens 130 and the fourth lens 140 is f234, and the following condition is satisfied: f1/f234=0.7515 .

In the imaging lens set of the first embodiment, the combined focal length of the second lens 120, the third lens 130, and the fourth lens 140 is f234, and the focal length of the fifth lens 150 is f5, and the following condition is satisfied: f234/f5= -1.6727.

In the imaging lens set of the first embodiment, the composite focal length of the first lens 110, the second lens 120, and the third lens 130 is f123, and the focal length of the fourth lens 140 is f4, and the following conditions are satisfied: f123/f4= 1.8554.

In the imaging lens set of the first embodiment, the composite focal length of the first lens 110, the second lens 120, and the third lens 130 is f123, and the combined focal length of the fourth lens 140 and the fifth lens 150 is f45, and the following is satisfied. Condition: f123/f45=0.0674.

In the imaging lens group of the first embodiment, the first lens 110 has a dispersion coefficient of V1, the second lens 120 has a dispersion coefficient of V2, and satisfies the following condition: V1 - V2 = 34.5.

In the imaging lens group of the first embodiment, the fourth lens 140 has a dispersion coefficient of V4, and the third lens 130 has a dispersion coefficient of V3 and satisfies the following condition: V4-V3 = 34.5.

In the imaging lens set of the first embodiment, the total focal length of the imaging lens group is f, the distance from the object side surface 111 to the imaging surface 180 of the first lens 110 on the optical axis 190 is TL, and the following condition is satisfied: f /TL=0.8281.

Refer to Table 1 and Table 2 below for reference.

Table 1 is the detailed structural data of the first embodiment of Fig. 1A, in which the unit of curvature radius, thickness and focal length is mm, and the surfaces 0-15 sequentially represent the surface from the object side to the image side. Table 2 is the aspherical data in the first embodiment, wherein the cone surface coefficients in the a-spherical curve equation of k, A, B, C, D, E, F, ... are high-order aspherical coefficients . In addition, the table of the following embodiments corresponds to the schematic diagram and the aberration diagram of each embodiment, and the definition of the data in the table is the same as the definitions of Table 1 and Table 2 of the first embodiment, and details are not described herein.

<Second embodiment>

2A and FIG. 2B, FIG. 2A is a schematic diagram of an imaging lens group according to a second embodiment of the present invention, and FIG. 2B is a spherical aberration and astigmatism of the imaging lens group of the second embodiment from left to right. And the distortion curve. As shown in FIG. 2A, the imaging lens assembly includes an aperture 200 and an optical group. The optical group sequentially includes a first lens 210, a second lens 220, a third lens 230, and a fourth lens 240 from the object side to the image side. The fifth lens 250, the infrared filter element 270, and the imaging surface 280, wherein the lens of the refractive lens group has five sheets. The aperture 200 is disposed between the image side surface 212 of the first lens 210 and the object.

The first lens 210 has a positive refractive power and is made of a plastic material. The object side surface 211 is convex at the near optical axis 290, and the image side surface 212 is convex at the near optical axis 290, and the object side surface 211 and the image side are Surface 212 is aspherical.

The second lens 220 has a negative refractive power and is made of a plastic material. The object side surface 221 is convex at the near optical axis 290, and the image side surface 222 is concave at the near optical axis 290, and the object side surface 221 and the image side are Surfaces 222 are all aspherical.

The third lens 230 has a negative refractive power and is made of a plastic material. The object side surface 231 is convex at the near optical axis 290, and the image side surface 232 is concave at the near optical axis 290, and the object side surface 231 and the image side are Surfaces 232 are all aspherical.

The fourth lens 240 has a positive refractive power and is made of a plastic material. The object side surface 241 is concave at the near optical axis 290, and the image side surface 242 is convex at the near optical axis 290, and the object side surface 241 and the image side are Surface 242 is aspherical.

The fifth lens 250 has a negative refractive power and is made of a plastic material, and the object side surface 251 is concave at the near optical axis 290, and the image side surface 252 is concave at the near optical axis 290, and the object side surface 251 and the image side are The surface 252 is aspherical, and at least one surface of the object side surface 251 and the image side surface 252 has at least one inflection point.

The infrared filter element 270 is made of glass and disposed between the fifth lens 250 and the imaging surface 280 without affecting the focal length of the imaging lens group.

Refer to Table 3 and Table 4 below.

In the second embodiment, the aspherical curve equation represents the form as in the first embodiment. In addition, the definitions of the parameters in the following table are the same as those in the first embodiment, and are not described herein.

With Table 3 and Table 4, the following data can be derived:

<Third embodiment>

3A and FIG. 3B, FIG. 3A is a schematic diagram of an imaging lens set according to a third embodiment of the present invention, and FIG. 3B is a spherical aberration and astigmatism of the imaging lens group of the third embodiment from left to right. And the distortion curve. As shown in FIG. 3A, the imaging lens assembly includes an aperture 300 and an optical group. The optical group sequentially includes a first lens 310, a second lens 320, a third lens 330, and a fourth lens 340 from the object side to the image side. The fifth lens 350, the infrared filter element 370, and the imaging surface 380, wherein the lens of the refractive lens group has five sheets. The aperture 300 is disposed between the image side surface 312 of the first lens 310 and the subject.

The first lens 310 has a positive refractive power and is made of a plastic material. The object side surface 311 is convex at the near optical axis 390, and the image side surface 312 is convex at the near optical axis 390, and the object side surface 311 and the image side are Surfaces 312 are all aspherical.

The second lens 320 has a negative refractive power and is made of a plastic material. The object side surface 321 is convex at the near optical axis 390, and the image side surface 322 is concave at the near optical axis 390, and the object side surface 321 and the image side are Surfaces 322 are all aspherical.

The third lens 330 has a positive refractive power and is made of a plastic material. The object side surface 331 is convex at the near optical axis 390, and the image side surface 332 is concave at the near optical axis 390, and the object side surface 331 and the image side are Surface 332 is aspherical.

The fourth lens 340 has a positive refractive power and is made of a plastic material. The object side surface 341 is concave at the near optical axis 390, and the image side surface 342 is convex at the near optical axis 390, and the object side surface 341 and the image side are Surfaces 342 are all aspherical.

The fifth lens 350 has a negative refractive power and is made of a plastic material. The object side surface 351 is concave at the near optical axis 390, and the image side surface 352 is concave at the near optical axis 390, and the object side surface 351 and the image side are The surface 352 is aspherical, and the object side surface 351 and the image side surface 352 have at least one inversion point.

The infrared filter element 370 is made of glass and disposed between the fifth lens 350 and the imaging surface 380 without affecting the focal length of the imaging lens group.

Refer to Table 5 and Table 6 below for reference.

In the third embodiment, the aspherical curve equation represents the form as in the first embodiment. In addition, the definitions of the parameters in the following table are the same as those in the first embodiment, and are not described herein.

With Table 5 and Table 6, the following data can be derived:

The imaging lens set provided by the invention can be made of plastic or glass. When the lens material is plastic, the production cost can be effectively reduced. When the lens is made of glass, the degree of freedom of the refractive power of the imaging lens set can be increased. In addition, the object side surface and the image side surface of the lens in the imaging lens group may be aspherical, and the aspheric surface can be easily formed into a shape other than the spherical surface, and more control variables are obtained to reduce the aberration and thereby reduce the number of lenses used. Therefore, the total length of the imaging lens group of the present invention can be effectively reduced.

In the imaging lens set provided by the present invention, in the case of a lens having a refractive power, if the surface of the lens is convex and the position of the convex surface is not defined, it indicates that the surface of the lens is convex at the near optical axis; When the concave surface is not defined and the concave position is not defined, it indicates that the lens surface is concave at the near optical axis.

The imaging lens set provided by the invention is more suitable for the optical system of moving focus, and has the characteristics of excellent aberration correction and good imaging quality, and can be applied to 3D (3D) image capturing, digital camera, and action in various aspects. In electronic imaging systems such as devices, digital tablets or car photography.

In the above, the above embodiments and drawings are only the preferred embodiments of the present invention, and the scope of the present invention is not limited thereto, that is, the equivalent changes and modifications made by the scope of the present invention are all It should be within the scope of the patent of the present invention.

100‧‧‧ aperture

110‧‧‧first lens

111‧‧‧Side side surface

112‧‧‧ image side surface

120‧‧‧second lens

121‧‧‧Side side surface

122‧‧‧ image side surface

130‧‧‧ third lens

131‧‧‧ object side surface

132‧‧‧Image side surface

140‧‧‧Fourth lens

141‧‧‧ object side surface

142‧‧‧ image side surface

150‧‧‧ fifth lens

151‧‧‧ object side surface

152‧‧‧ image side surface

170‧‧‧Infrared filter components

180‧‧‧ imaging surface

190‧‧‧ optical axis

Claims (18)

An imaging lens group comprising: an aperture from the object side to the image side; a first lens having a positive refractive power, the object side surface being convex at a near optical axis, and the image side surface being convex at a near optical axis, At least one surface of the object side surface and the image side surface is aspherical; a second lens has a negative refractive power, and the object side surface is convex at a near optical axis, and at least one surface of the object side surface and the image side surface is aspherical a third lens having a refractive power, the image side surface having a concave surface at a near optical axis, and at least one surface of the object side surface and the image side surface being aspherical; a fourth lens having a positive refractive power and an object side surface thereof The near optical axis is a concave surface, and the image side surface is convex at the near optical axis, and at least one surface of the object side surface and the image side surface is aspherical; a fifth lens has a negative refractive power, and the object side surface is near the optical axis. a concave surface, wherein the image side surface has a concave surface at a near optical axis, and at least one surface of the object side surface and the image side surface is aspherical, and at least one surface of the object side surface and the image side surface has at least one inflection point; wherein Second lens, third lens and fourth lens The focal length is f234, the focal length of the fifth lens is f5, and the following condition is satisfied: -1.8<f234/f5<-1.0; wherein the fourth lens has a dispersion coefficient of V4, and the third lens has a dispersion coefficient of V3. And the following conditions are met: 30 < V4-V3 < 42. The imaging lens set according to claim 1, wherein the object side surface of the second lens is convex at a near optical axis, and the image side surface is concave at a near optical axis; the object side surface of the third lens is at a near optical axis The convex surface and the image side surface are concave at the near optical axis. The imaging lens set according to claim 1, wherein the focal length of the first lens is f1, the focal length of the second lens is f2, and the following condition is satisfied: -0.75 < f1/f2 < -0.4. The imaging lens set according to claim 1, wherein the focal length of the second lens is f2, the focal length of the fourth lens is f4, and the following condition is satisfied: -2.6 < f2 / f4 < - 1.8. The imaging lens set according to claim 1, wherein the focal length of the fourth lens is f4, the focal length of the fifth lens is f5, and the following condition is satisfied: -1.35 < f4 / f5 < -0.9. The imaging lens set according to claim 1, wherein the focal length of the first lens is f1, the focal length of the third lens is f3, and the following condition is satisfied: -0.1 < f1/f3 < 0.15. The imaging lens set according to claim 1, wherein the focal length of the second lens is f2, the focal length of the fifth lens is f5, and the following condition is satisfied: 1.8 < f2 / f5 < 3.1. The imaging lens set according to claim 1, wherein the focal length of the first lens is f1, the focal length of the fourth lens is f4, and the following condition is satisfied: 0.9 < f1/f4 < 1.5. The imaging lens set according to claim 1, wherein a focal length of the first lens is f1, a combined focal length of the second lens and the third lens is f23, and the following condition is satisfied: -0.7 < f1/f23 < -0.5. The imaging lens set according to claim 1, wherein the combined focal length of the second lens and the third lens is f23, and the combined focal length of the fourth lens and the fifth lens is f45, and the following condition is satisfied: -0.35<f23/ F45 <-0.05. The imaging lens set according to claim 1, wherein a composite focal length of the first lens and the second lens is f12, a combined focal length of the third lens and the fourth lens is f34, and the following condition is satisfied: 1.4<f12/f34 <2.8. The imaging lens set according to claim 1, wherein the combined focal length of the third lens and the fourth lens is f34, the focal length of the fifth lens is f5, and the following condition is satisfied: -1.4 < f34 / f5 < -0.9. The imaging lens set according to claim 1, wherein the focal length of the first lens is f1, the combined focal length of the second lens, the third lens and the fourth lens is f234, and the following condition is satisfied: 0.6 < f1/f234 < 1.5. The imaging lens set according to claim 1, wherein the second lens and the third lens have a combined focal length of f23, the fourth lens has a focal length of f4, and satisfies the following condition: -2.3 < f23 / f4 < - 1.5. The imaging lens set according to claim 1, wherein the first lens, the second lens and the third lens have a combined focal length of f123, the fourth lens has a focal length of f4, and satisfies the following condition: 1.6<f123/f4< 2.7. The imaging lens set according to claim 1, wherein the first lens, the second lens and the third lens have a combined focal length of f123, and the fourth lens and the fifth lens have a combined focal length of f45, and satisfy the following condition: 0.05 <f123/f45<0.4. The imaging lens set according to claim 1, wherein the first lens has a dispersion coefficient of V1, the second lens has a dispersion coefficient of V2, and satisfies the following condition: 30 < V1 - V2 < 42. The imaging lens set according to claim 1, wherein the total focal length of the imaging lens group is f, the distance from the object side surface of the first lens to the imaging surface on the optical axis is TL, and the following condition is satisfied: 0.6 < f /TL<0.95.