CN105866934A - Four-sheet type imaging lens group - Google Patents

Abstract

The invention relates to a four-sheet type imaging lens group. The four-sheet type imaging lens group comprises a fixed diaphragm and an optical group; the optical group comprises a first lens, a second lens, a third lens and a fourth lens; the first lens has positive refractive power adjacent to a center optical axis; a surface of the first lens, which faces an object side, is a convex surface; the second lens has positive refractive power adjacent to the center optical axis; a surface of the second lens, which faces an image side, is a convex surface; at least one surface of the second lens is an aspheric surface; the third lens has negative refractive power adjacent to the center optical axis; a surface of the third lens, which faces the image side, is a convex surface; at least one surface of the third lens is an aspheric surface; the fourth lens has refractive power adjacent to the center optical axis; a surface of the fourth lens, which faces the object side, is a convex surface; and a surface of the fourth lens, which faces the image side, is a concave surface; and at least one surface of the fourth lens has points of inflexion. The optical group satisfies the following conditions that: 2.5<OAL/EPD<4.5; Vd2-Vd3>20; and 1.0<OL/SigmaLC<1.5.

Description

Four-piece type imaging lens group

Technical field

The present invention relates to a kind of camera lens, particularly relate to a kind of four-piece type imaging lens group.

Background technology

Existing imaging lens set, apply to mobile phone, Smartphone, panel computer, Notebook computer and image the imaging lens set in the middle of first-class electronic product.Along with this electron-like Product constantly develops, and is increasingly towards compact design inclination, but requires efficiently simultaneously Can, therefore, make imaging lens set send out towards the slim size of entirety more close mode jointly Exhibition, and the areas imaging of high image quality is met in order to improve resolution, such as resolution specification is The full HD (High Definition) of 1920 × 1080, imaging lens set is also required to towards wider The direction at angle is developed.

And existing imaging lens set, although disclose the imaging lens set of four-piece type, but the most not Slim, the demand of Radix Rumicis can be met further.

Therefore, in order to be able to allow electronic product have compact and dynamical advantage, Yi Zhongke concurrently So that the slim size of entirety more close mode, and the four-piece type imaging eyeglass of resolution can be improved Needed for group is for existing market.

Summary of the invention

It is an object of the invention to provide a kind of can the slim and four-piece type imaging lens of Radix Rumicis Group.

Four-piece type imaging lens group of the present invention, comprises a fixed diaphram, and an optics group, This optics group includes first, second, the 3rd and the 4th eyeglass, arrangement The mode order from thing side to image side is: this first eyeglass, the most in the wrong having near optical axis Luminous power and be convex surface towards thing side；This second eyeglass, has positive refractive power near optical axis And be convex surface towards image side, at least a face is aspheric surface；3rd eyeglass, near light Having negative refractive power near axle and be convex surface towards image side, at least a face is aspheric surface；Should 4th eyeglass, has refractive power, towards thing side for convex surface facing image side to be near optical axis Concave surface, at least there is the point of inflexion in a face.

And the present invention meets following condition: 2.5<OAL/EPD<4.5, Vd2-Vd3>20, 1.0 < OL/ Σ LC < 1.5, wherein, OAL on optical axis this first eyeglass thing side to becoming Distance between image planes, EPD is the Entry pupil diameters of this imaging lens group, and Vd2 is this second eyeglass Abbe number, Vd3 is the Abbe number of the 3rd eyeglass, and OL is this first eyeglass on optical axis Thing side is to the distance between the 4th eyeglass image side surface, and Σ LC is all tools in this imaging lens group There is the center thickness summation of refractive power eyeglass.

Four-piece type imaging lens group of the present invention, meets following condition: 0.2 < YC42/OAL < 0.4, wherein, the 4th eyeglass image side surface has at least one and hangs down with one In the critical point C, this critical point C that the tangent plane of optical axis is tangent with the vertical dimension of optical axis it is directly YC42。

Four-piece type imaging lens group of the present invention, meets following condition: 0≤| Vd1-Vd2 | < 5, wherein, Vd1 is the Abbe number of this first eyeglass.

Four-piece type imaging lens group of the present invention, meets following condition: 0.5 < D12/D23 < 3.8, wherein, D12 is this first eyeglass and this second eyeglass distance on optical axis, D23 For this second eyeglass and the 3rd eyeglass distance on optical axis.

Four-piece type imaging lens group of the present invention, meets following condition: 1.0 < (| R1 |+| R3 |)/(| R5 |+| R6 |) < 9.0, wherein, R1 is the curvature of this first eyeglass thing side Radius, R3 is the radius of curvature of this second eyeglass thing side, and R5 is the 3rd eyeglass thing side Radius of curvature, R6 is the radius of curvature of the 3rd eyeglass image side surface.

Four-piece type imaging lens group of the present invention, meets following condition: 4 < SD21/ | SAG21 | < 18, wherein, SD21 is maximum effective diameter on this second eyeglass thing side, | SAG21 | is for being perpendicular to the position of optical axis to this second eyeglass at this second eyeglass maximum effective diameter The depth distance of thing center side point.

Four-piece type imaging lens group of the present invention, meets following condition: 4.0 < OAL/ (LC1+D12) < 6.5, wherein, LC1 is the center thickness of this first eyeglass, and D12 is for being somebody's turn to do First eyeglass and this second eyeglass distance on optical axis.

Four-piece type imaging lens group of the present invention, this fixed diaphram is arranged on object and is somebody's turn to do Between the second eyeglass.

Four-piece type imaging lens group of the present invention, the 3rd and the 4th eyeglass is all plastic cement Material.

The beneficial effects of the present invention is: coordinate face type design and by meeting 2.5 < OAL/EPD<4.5, Vd2-Vd3>20,1.0<OL/ Σ LC<1.5, reach slim and wide The goal of the invention at angle.

Accompanying drawing explanation

Fig. 1 is an optical texture schematic diagram, and the tool of four-piece type imaging lens set of the present invention is described Body embodiment one；

Fig. 2 is a schematic diagram, and the spherical aberration of specific embodiment one is described；

Fig. 3 is a schematic diagram, and the astigmatism of specific embodiment one is described；

Fig. 4 is a schematic diagram, and the distortion aberration of specific embodiment one is described；

Fig. 5 is a form, and the design data of specific embodiment one is described；

Fig. 6 is a form, and the asphericity coefficient of specific embodiment one is described, therein 1 to 8 optical surfaces refer to first respectively to octahedral；

Fig. 7 is an optical texture schematic diagram, and the tool of four-piece type imaging lens set of the present invention is described Body embodiment two；

Fig. 8 is a schematic diagram, and the spherical aberration of specific embodiment two is described；

Fig. 9 is a schematic diagram, and the astigmatism of specific embodiment two is described；

Figure 10 is a schematic diagram, and the distortion aberration of specific embodiment two is described；

Figure 11 is a form, and the design data of specific embodiment two is described；

Figure 12 is a form, and the asphericity coefficient of specific embodiment two is described, therein 1 First is referred to respectively to octahedral to 8 optical surfaces；

Figure 13 is an optical texture schematic diagram, and four-piece type imaging lens set of the present invention is described Specific embodiment three；

Figure 14 is a schematic diagram, and the spherical aberration of specific embodiment three is described；

Figure 15 is a schematic diagram, and the astigmatism of specific embodiment three is described；

Figure 16 is a schematic diagram, and the distortion aberration of specific embodiment three is described；

Figure 17 is a form, and the design data of specific embodiment three is described；

Figure 18 is a form, and the asphericity coefficient of specific embodiment three is described, therein 1 First is referred to respectively to octahedral to 8 optical surfaces；

Figure 19 is an optical texture schematic diagram, and four-piece type imaging lens set of the present invention is described Specific embodiment four；

Figure 20 is a schematic diagram, and the spherical aberration of specific embodiment four is described；

Figure 21 is a schematic diagram, and the astigmatism of specific embodiment four is described；

Figure 22 is a schematic diagram, and the distortion aberration of specific embodiment four is described；

Figure 23 is a form, and the design data of specific embodiment four is described；

Figure 24 is a form, and the asphericity coefficient of specific embodiment four is described, therein 1 First is referred to respectively to octahedral to 8 optical surfaces；

Figure 25 is an optical texture schematic diagram, and four-piece type imaging lens set of the present invention is described Specific embodiment five；

Figure 26 is a schematic diagram, and the spherical aberration of specific embodiment five is described；

Figure 27 is a schematic diagram, and the astigmatism of specific embodiment five is described；

Figure 28 is a schematic diagram, and the distortion aberration of specific embodiment five is described；

Figure 29 is a form, and the design data of specific embodiment five is described；

Figure 30 is a form, and the asphericity coefficient of specific embodiment five is described, therein 1 First is referred to respectively to octahedral to 8 optical surfaces；

Figure 31 is a form, and four-piece type imaging lens group specific embodiment one of the present invention is described To every optical parametric of five.

Detailed description of the invention

Below in conjunction with the accompanying drawings and embodiment the present invention is described in detail.

Before the present invention is described in detail, it shall be noted that in the following description content, similar Element be to be identically numbered to represent, and each embodiment lens group wavelength is 587nm.

Refering to Fig. 1 to Fig. 6, four-piece type imaging lens group of the present invention comprises a fixed diaphram 1 And an optics group 2, this optics group 2 include one first, one second, one the 3rd and One the 4th eyeglass 21,22,23,24, the arrangement mode order from thing side to image side is:

This first eyeglass 21 has positive refractive power and the face (the towards thing side near the optical axis Simultaneously) being convex surface, this first eyeglass 21 also has the face (the second face) towards image side；

This second eyeglass 22 has refractive power and the face (the towards thing side near the optical axis Three faces) it is concave surface, is convex surface towards the face (fourth face) of image side, at least a face is non- Sphere, when being embodied as, this second eyeglass 22 has positive refractive power near optical axis；

3rd eyeglass 23 has negative refractive power and the face (the towards image side near the optical axis Hexahedro) it is convex surface, at least a face is aspheric surface, at least one, the 3rd eyeglass 23 There is the point of inflexion in face, and the 3rd eyeglass 23 also has the face (the 5th face) towards thing side；

4th eyeglass 24 has refractive power near the optical axis, towards the face (the of thing side Seven faces) for being concave surface convex surface facing image side, at least there is the point of inflexion in a face, the 4th eyeglass 24 also have the face (octahedral) towards image side；

This fixed diaphram 1 is arranged between object and this second eyeglass 22, and the 3rd eyeglass 23 and the 4th eyeglass 24 be all plastic cement material.

And four-piece type imaging lens group of the present invention meets following condition:

2.5 < OAL/EPD < 4.5, (1)

Vd2-Vd3 > 20, (2)

1.0 < OL/ Σ LC < 1.5, (3)

0.2 < YC42/OAL < 0.4, (4)

0≤| Vd1-Vd2 | < 5, (5)

0.5 < D12/D23 < 3.8, (6)

1.0 < (| R1 |+| R3 |)/(| R5 |+| R6 |) < 9.0, (7)

4 < SD21/ | SAG21 | < 18, (8)

4.0 < OAL/ (LC1+D12) < 6.5, (9)

0.5 < tan (FOV/2)/YC42 < 1.8, (10)

0 < f2/Vd2 < 0.2, (11)

0.4 < LC3/LC2 < 1.5, (12)

0.2 < EPD/SD42 < 0.4, (13)

0.1 < | SAG32 |+| SAG41 | < 0.5, (14)

Wherein, OAL be on optical axis this first eyeglass 21 thing side to the distance between imaging surface, EPD is the Entry pupil diameters of this imaging lens group, and Vd1 is the Abbe number of this first eyeglass 21, Vd2 is the Abbe number of this second eyeglass 22, and Vd3 is the Abbe number of the 3rd eyeglass 23, OL For the distance between this first eyeglass 21 thing side on optical axis to the 4th eyeglass 24 image side surface, Σ LC is all center thickness summations with refractive power eyeglass in this imaging lens group, the 4th There is at least one tangent with tangent plane being perpendicular to optical axis critical on eyeglass 24 image side surface Point C, this critical point C are YC42 with the vertical dimension of optical axis, and D12 is this first eyeglass 21 Towards face (the second face) and this second eyeglass 22 of image side towards the face (the 3rd face) of thing side Distance on optical axis, when this fixed diaphram 1 is arranged between object and this first eyeglass 21 Time, D12 refers to the thickness/interval of second in Figure of description, when this fixed diaphram 1 sets When putting between this first eyeglass 21 and the second eyeglass 22, D12 refers in Figure of description second Thickness/the interval in face and the thickness of fixed diaphram/interval sum；D23 is this second eyeglass 22 Towards face (fourth face) and the 3rd eyeglass 23 of image side towards the face (the 5th face) of thing side Distance on optical axis, refers to the thickness/interval of fourth face in Figure of description；R1 be this The radius of curvature of one eyeglass 21 thing side, R3 is the curvature half of this second eyeglass 22 thing side Footpath, R5 is the radius of curvature of the 3rd eyeglass 23 thing side, and R6 is the 3rd eyeglass 23 picture The radius of curvature of side, SD21 is maximum effective diameter on this second eyeglass 22 thing side, | SAG21 | is for being perpendicular to the position of optical axis to this second mirror at the maximum effective diameter of this second eyeglass 22 The depth distance of sheet 22 thing center side point, LC1 is the center thickness of this first eyeglass 21, Thickness/the interval of first in finger Figure of description；LC2 is the center of this second eyeglass 22 Thickness, refers to the thickness/interval of in Figure of description the 3rd；FOV is this imaging lens group In maximum field of view angle, f2 is the focal length value of this second eyeglass 22, and LC3 is the 3rd eyeglass The center thickness of 23, refers to the thickness/interval of in Figure of description the 5th；| SAG32 | is this 3rd eyeglass 23 is perpendicular to optical axis position corresponding to being somebody's turn to do at the maximum effective diameter in the face of image side The degree of depth at minute surface center, | SAG41 | is effective towards the maximum in the face of thing side for the 4th eyeglass 24 Being perpendicular to the optical axis position degree of depth corresponding to this minute surface center at footpath, SD42 is the 4th eyeglass 24 Maximum effective diameter on image side surface.

And aforementioned aspheric type meets following equation:

$\begin{array}{c}z=\frac{{\mathrm{ch}}^2}{1+{[1-(k+1)c^2{h}^2]}^{0.5}}+{\mathrm{Ah}}^4+{\mathrm{Bh}}^6+{\mathrm{Ch}}^8+{\mathrm{Dh}}^{10}+{\mathrm{Eh}}^{12}+{\mathrm{Fh}}^{14}+{\mathrm{Gh}}^{16}\\ +{\mathrm{Hh}}^{18}+{\mathrm{Jh}}^{20}+...\end{array}$

Wherein z is the position making reference along optical axis direction in the position that height is h with surface vertices Value；K is cone normal manner amount；C is the inverse of radius of curvature；A、B、C、D、E、F、G、 H, J are order aspherical coefficients.

When being embodied as, this four-piece type imaging lens group also includes a filter sheet, and this filter sheet has Have one towards the face (the 9th face) of thing side, one towards the face (the tenth face) of image side；

Additionally, this four-piece type imaging lens group can also include a protection eyeglass, this protection eyeglass Have one towards the face (the tenth one side) of thing side, one towards the face (dodecahedro) of image side.

Fig. 1 to Fig. 6 is specific embodiment one, and related data is: OAL=2.079mm, EPD=0.555mm, f2=1.147mm, Vd1=55.6, Vd2=55.6, Vd3=22.4, SD21=0.684mm, SD42=2.140mm, R1=0.963mm, R3=-1.750mm, R5=-0.228mm, R6=-0.482mm, Σ LC=1.083mm, FOV=87.4 °, LC1=0.234mm, LC2=0.346mm, LC3=0.18mm, D12=0.123mm, D23=0.117mm, OL=1.348mm, YC42=0.795mm, | SAG21 |=0.073mm, | SAG32 |=0.259mm, | SAG41 |=0.092mm.

Fig. 7 to Figure 12 is specific embodiment two, and related data is: OAL=4.45mm, EPD=1.428mm, f2=6.411mm, Vd1=55.6, Vd2=55.6, Vd3=22.4, SD21=1.528mm, SD42=4.245mm, R1=1.370mm, R3=-5.596mm, R5=-1.318mm, R6=-5.160mm, Σ LC=2.151mm, FOV=76.0 °, LC1=0.395mm, LC2=0.361mm, LC3=0.523mm, D12=0.482mm, D23=0.138mm, OL=2.996mm, YC42=1.192mm, | SAG21 |=0.121mm, | SAG32 |=0.244mm, | SAG41 |=0.207mm.

Figure 13 to Figure 18 is specific embodiment three, and related data is: OAL=3.410mm, EPD=1.123mm, f2=4.237mm, Vd1=57.1, Vd2=55.6, Vd3=22.4, SD21=1.241mm, SD42=3.751mm, R1=1.359mm, R3=-3.692mm, R5=-0.388mm, R6=-0.732mm, Σ LC=1.890mm, FOV=87.0 °, LC1=0.452mm, LC2=0.402mm, LC3=0.200mm, D12=0.253mm, D23=0.221mm, OL=2.390mm, YC42=1.216mm, | SAG21 |=0.144mm, | SAG32 |=0.396mm, | SAG41 |=0.004mm.

Figure 19 to Figure 24 is specific embodiment four, and related data is: OAL=2.019mm, EPD=0.479mm, f2=1.063mm, Vd1=55.6, Vd2=55.6, Vd3=22.4, SD21=0.540mm, SD42=2.078mm, R1=1.041mm, R3=-2.545mm, R5=-0.201mm, R6=-0.289mm, Σ LC=1.067mm, FOV=94.6 °, LC1=0.233mm, LC2=0.379mm, LC3=0.18mm, D12=0.098mm, D23=0.135mm, OL=1.325mm, YC42=0.71mm, | SAG21 |=0.034mm, | SAG32 |=0.307mm, | SAG41 |=0.009mm.

Figure 25 to Figure 30 is specific embodiment five, and related data is: OAL=2.14mm, EPD=0.612mm, f2=9.465mm, Vd1=55.6, Vd2=55.6, Vd3=22.4, SD21=0.831mm, SD42=2.206mm, R1=1.152mm, R3=-1.018mm, R5=-0.347mm, R6=-0.420mm, Σ LC=1.011mm, FOV=88.0 °, LC1=0.326mm, LC2=0.220mm, LC3=0.181mm, D12=0.142mm, D23=0.068mm, OL=1.246mm, YC42=0.753mm, | SAG21 |=0.157mm, | SAG32 |=0.160mm, | SAG41 |=0.008mm.

Refering to Figure 31, for by the specific embodiment one to five of four-piece type imaging lens group of the present invention Related data substitutes in the numerical value of conditional (1) to (14).

In sum, effect of four-piece type imaging lens group of the present invention is, coordinates setting of face type Count and by meeting conditional (1) to (14), reach the slim and goal of the invention of Radix Rumicis.

Claims (27)

1. a four-piece type imaging lens group, it is characterised in that it comprises:

One fixed diaphram；And

One optics group, this optics group includes one first, one second, one 3rd and the 4th eyeglass, the arrangement mode order from thing side to image side is:

This first eyeglass, has positive refractive power and towards thing side near optical axis For convex surface；

This second eyeglass, has positive refractive power and towards image side near optical axis For convex surface, at least a face is aspheric surface；

3rd eyeglass, has negative refractive power and towards image side near optical axis For convex surface, at least a face is aspheric surface；

4th eyeglass, has refractive power near optical axis, towards thing side is being Being concave surface convex surface facing image side, at least there is the point of inflexion in a face；

And meet following condition:

2.5 < OAL/EPD < 4.5,

Vd2-Vd3 > 20,

1.0 < OL/ Σ LC < 1.5,

Wherein, OAL be on optical axis this first eyeglass thing side between imaging surface Distance, EPD is the Entry pupil diameters of this imaging lens group, and Vd2 is the Abbe number of this second eyeglass, Vd3 is the Abbe number of the 3rd eyeglass, OL be on optical axis this first eyeglass thing side to should Distance between the 4th eyeglass image side surface, Σ LC is all in this imaging lens group to have refractive power The center thickness summation of eyeglass.

Four-piece type imaging lens group the most according to claim 1, it is characterised in that: full Be enough to lower condition: 0.2 < YC42/OAL < 0.4, wherein, the 4th eyeglass image side surface has Have the tangent critical point C, this critical point C of at least one and tangent plane being perpendicular to optical axis with The vertical dimension of optical axis is YC42.

Four-piece type imaging lens group the most according to claim 1, it is characterised in that: full Be enough to lower condition: 0≤| Vd1-Vd2 | < 5, wherein, Vd1 is the Abbe number of this first eyeglass.

Four-piece type imaging lens group the most according to claim 1, it is characterised in that: full Be enough to lower condition: 0.5 < D12/D23 < 3.8, wherein, D12 be this first eyeglass with this Two eyeglasses distance on optical axis, D23 is this second eyeglass with the 3rd eyeglass on optical axis Distance.

Four-piece type imaging lens group the most according to claim 1, it is characterised in that: full Be enough to lower condition: 1.0 < (| R1 |+| R3 |)/(| R5 |+| R6 |) < 9.0, wherein, R1 be this first The radius of curvature of eyeglass thing side, R3 is the radius of curvature of this second eyeglass thing side, and R5 is The radius of curvature of the 3rd eyeglass thing side, R6 is the curvature half of the 3rd eyeglass image side surface Footpath.

Four-piece type imaging lens group the most according to claim 1, it is characterised in that: full Be enough to lower condition: 4 < SD21/ | SAG21 | < 18, wherein, SD21 is this second eyeglass thing Maximum effective diameter on side, | SAG21 | is for being perpendicular to optical axis at this second eyeglass maximum effective diameter Position to the depth distance of this second eyeglass thing center side point.

Four-piece type imaging lens group the most according to claim 1, it is characterised in that: full Be enough to lower condition: 4.0 < OAL/ (LC1+D12) < 6.5, wherein, LC1 is this first mirror The center thickness of sheet, D12 is this first eyeglass and this second eyeglass distance on optical axis.

Four-piece type imaging lens group the most according to claim 1, it is characterised in that: should Fixed diaphram is arranged between object and this second eyeglass.

Four-piece type imaging lens group the most according to claim 1, it is characterised in that: should 3rd and the 4th eyeglass is all plastic cement material.

10. a four-piece type imaging lens group, it is characterised in that it comprises:

One fixed diaphram；And

One optics group, this optics group includes one first, one second, one 3rd and the 4th eyeglass, the arrangement mode order from thing side to image side is:

This first eyeglass, has positive refractive power and towards thing side near optical axis For convex surface；

This second eyeglass, has refractive power near the optical axis and towards thing side is being Concave surface is convex surface towards image side, its at least a face be aspheric surface；

3rd eyeglass, has negative refractive power and towards image side near optical axis For convex surface, at least a face is aspheric surface；

4th eyeglass, has refractive power near optical axis, towards thing side is being Being concave surface convex surface facing image side, at least there is the point of inflexion in a face；

This fixed diaphram is arranged between object and this second eyeglass, and meet below Condition:

2.5 < OAL/EPD < 4.5,

0.5 < tan (FOV/2)/YC42 < 1.8,

1.0 < OL/ Σ LC < 1.5,

Wherein, OAL be on optical axis this first eyeglass thing side between imaging surface Distance, EPD is the Entry pupil diameters of this imaging lens group, and the 4th eyeglass image side surface has At least one critical point C tangent with a tangent plane being perpendicular to optical axis, this critical point C and light The vertical dimension of axle be YC42, FOV be the maximum field of view angle in this imaging lens group, OL For the distance between this first eyeglass thing side on optical axis to the 4th eyeglass image side surface, Σ LC For center thickness summations with refractive power eyeglass all in this imaging lens group.

11. four-piece type imaging lens groups according to claim 10, it is characterised in that: Meet following condition: 0.2 < YC42/OAL < 0.4.

12. four-piece type imaging lens groups according to claim 10, it is characterised in that: Meeting following condition: 0 < f2/Vd2 < 0.2, wherein, f2 is the focal length value of this second eyeglass, Vd2 is the Abbe number of this second eyeglass.

13. four-piece type imaging lens groups according to claim 10, it is characterised in that: Meet following condition: 0.5 < D12/D23 < 3.8, wherein, D12 be this first eyeglass with should Second eyeglass distance on optical axis, D23 is this second eyeglass with the 3rd eyeglass in optical axis On distance.

14. four-piece type imaging lens group according to claim 10, it is characterised in that: Meeting following condition: 4.0 < OAL/ (LC1+D12) < 6.5, wherein, LC1 is this first mirror The center thickness of sheet, D12 is this first eyeglass and this second eyeglass distance on optical axis.

15. four-piece type imaging lens groups according to claim 10, it is characterised in that: Meet following condition: 1.0 < (| R1 |+| R3 |)/(| R5 |+| R6 |) < 9.0, wherein, R1 be this The radius of curvature of one eyeglass thing side, R3 is the radius of curvature of this second eyeglass thing side, R5 For the radius of curvature of the 3rd eyeglass thing side, R6 is the curvature half of the 3rd eyeglass image side surface Footpath.

16. four-piece type imaging lens groups according to claim 10, it is characterised in that: Meeting following condition: 0.4 < LC3/LC2 < 1.5, wherein, LC2 is this second eyeglass Center thickness, LC3 is the center thickness of the 3rd eyeglass.

17. four-piece type imaging lens groups according to claim 10, it is characterised in that: Meeting following condition: 0≤| Vd1-Vd2 | < 5, wherein, Vd1 is the Abbe of this first eyeglass Number, Vd2 is the Abbe number of this second eyeglass.

18. 1 kinds of four-piece type imaging lens groups, it is characterised in that it comprises:

One fixed diaphram；And

One optics group, this optics group includes one first, one second, one 3rd and the 4th eyeglass, the arrangement mode order from thing side to image side is:

This first eyeglass, has positive refractive power near optical axis；

This second eyeglass, has positive refractive power near the optical axis, and at least one Individual face is aspheric surface；

3rd eyeglass, has refractive power near optical axis, at least one Face is aspheric surface；

4th eyeglass, has refractive power near optical axis, at least one There is the point of inflexion in face；

This fixed diaphram is arranged between object and this second eyeglass, and meet below Condition:

0.2 < EPD/SD42 < 0.4,

0.1 < | SAG32 |+| SAG41 | < 0.5,

1.0 < OL/ Σ LC < 1.5,

Wherein, EPD is the Entry pupil diameters of this imaging lens group, and SD42 is the 4th Maximum effective diameter on eyeglass image side surface, | SAG32 | for the 3rd eyeglass towards image side face Being perpendicular to the optical axis position degree of depth corresponding to this minute surface center at big effective diameter, | SAG41 | is this 4th eyeglass is perpendicular to optical axis position corresponding to this mirror at the maximum effective diameter in the face of thing side The degree of depth at center, face, OL be on optical axis this first eyeglass thing side to the 4th eyeglass image side Distance between face, Σ LC is all center thickness with refractive power eyeglass in this imaging lens group Degree summation.

19. four-piece type imaging lens groups according to claim 18, it is characterised in that: Meeting following condition: 4 < SD21/ | SAG21 | < 18, wherein, SD21 is this second eyeglass Maximum effective diameter on thing side, | SAG21 | is for being perpendicular to light at this second eyeglass maximum effective diameter The position of axle is to the depth distance of this second eyeglass thing center side point.

20. four-piece type imaging lens groups according to claim 18, it is characterised in that: Meet following condition: 0.2 < YC42/OAL < 0.4, wherein, on the 4th eyeglass image side surface There is at least one the critical point C, this critical point C tangent with a tangent plane being perpendicular to optical axis It is YC42, OAL for this first eyeglass thing side on optical axis to becoming with the vertical dimension of optical axis Distance between image planes.

21. four-piece type imaging lens groups according to claim 18, it is characterised in that: Meet following condition: 0≤| Vd1-Vd2 | < 5, wherein, Vd1 be this first eyeglass Ah Shellfish number, Vd2 is the Abbe number of this second eyeglass.

22. four-piece type imaging lens group according to claim 18, it is characterised in that: Meet following condition: 0.5 < D12/D23 < 3.8, wherein, D12 be this first eyeglass with should Second eyeglass distance on optical axis, D23 is this second eyeglass with the 3rd eyeglass in optical axis On distance.

23. four-piece type imaging lens group according to claim 18, it is characterised in that: Meeting following condition: 4.0 < OAL/ (LC1+D12) < 6.5, wherein, OAL is at optical axis This first eyeglass thing side upper is to the distance between imaging surface, and LC1 is the center of this first eyeglass Thickness, D12 is this first eyeglass and this second eyeglass distance on optical axis.

24. four-piece type imaging lens groups according to claim 18, it is characterised in that: Meet following condition: 1.0 < (| R1 |+| R3 |)/(| R5 |+| R6 |) < 9.0, wherein, R1 be this The radius of curvature of one eyeglass thing side, R3 is the radius of curvature of this second eyeglass thing side, R5 For the radius of curvature of the 3rd eyeglass thing side, R6 is the curvature half of the 3rd eyeglass image side surface Footpath.

25. four-piece type imaging lens groups according to claim 18, it is characterised in that: There is the point of inflexion in a 3rd eyeglass at least face.

26. four-piece type imaging lens groups according to claim 18, it is characterised in that: 3rd eyeglass has negative refractive power near optical axis.

27. four-piece type imaging lens groups according to claim 18, it is characterised in that: This first eyeglass is being convex surface towards thing side near the optical axis, and this second eyeglass is near light Axle is neighbouring is convex surface towards image side, and the 3rd eyeglass is being convex towards image side near optical axis Face, the 4th eyeglass near the optical axis towards thing side for being concave surface convex surface facing image side.