CN111474674A

CN111474674A - Optical imaging system

Info

Publication number: CN111474674A
Application number: CN202010362376.2A
Authority: CN
Inventors: 王�锋; 孙加安; 周明明; 马庆鸿; 万良伟
Original assignee: Huizhou Xingjuyu Optical Co ltd
Current assignee: Huizhou Xingjuyu Optical Co ltd
Priority date: 2020-04-30
Filing date: 2020-04-30
Publication date: 2020-07-31

Abstract

The invention provides an optical imaging system, comprising, in order from an object side to an image side: a first lens, a second lens, a third lens, a fourth lens and a fifth lens; the object side surface of the second lens is provided with at least one point of inflection; the object side surface of the third lens is a concave surface; the focal length of the third lens is f3, the distance from the vertical projection point of the maximum effective radius position of the object side surface of the third lens on the horizontal optical axis to the intersection point of the object side surface of the third lens and the optical axis is SAG31, and the following relational expression is satisfied: 2< f3/SAG31< 5. The invention has the beneficial effects that: the infrared imaging and depth perception are realized under the condition of ensuring compact structure, and the advantages of better imaging quality, lower production cost and the like are achieved; by using the lens made of the visible light filtering material, most visible light can be filtered by the lens, so that infrared imaging is clearer, and less visible light interference is caused.

Description

Optical imaging system

[ technical field ] A method for producing a semiconductor device

The invention relates to the technical field of optical lenses, in particular to an optical imaging system.

[ background of the invention ]

In recent years, with the rise of smart phones, the demand of miniaturized camera lenses is increasing, and the photosensitive devices of general camera lenses are not limited to two types, namely, a Charge Coupled Device (CCD) or a Complementary Metal-oxide semiconductor (CMOS) Sensor, and due to the advanced semiconductor manufacturing process, the pixel size of the photosensitive devices is reduced, and in addition, the current electronic products are developed with a good function, a light weight, a small size and a light weight, so that the miniaturized optical imaging system with good imaging quality is the mainstream in the current market.

In the related art, in order to obtain better imaging quality, a multi-piece lens structure is often adopted in a lens mounted on a mobile phone camera, a television, a motion sensing game machine and the like, but with the increase of lenses, the lens is heavy in volume, the production cost is increased, and the imaging quality is reduced.

[ summary of the invention ]

Based on this, it is necessary to design an optical imaging system, which has the advantages of good imaging quality, low production cost, clearer infrared imaging, less interference from visible light and the like under the condition of ensuring compact structure.

In order to achieve the purpose, the technical scheme provided by the invention is as follows:

an optical imaging system, comprising, in order from an object side to an image side: a first lens, a second lens, a third lens, a fourth lens and a fifth lens;

the object side surface of the second lens is provided with at least one point of inflection; the object side surface of the third lens is a concave surface;

the focal length of the third lens is f3, the distance from the vertical projection point of the maximum effective radius position of the object side surface of the third lens on the horizontal optical axis to the intersection point of the object side surface of the third lens and the optical axis is SAG31, and the following relational expression is satisfied:

2<f3/SAG31<5。

preferably, the distance between the vertical projection point of the maximum effective radius position of the object-side surface of the third lens on the horizontal optical axis and the intersection point of the object-side surface and the optical axis of the third lens is SAG31, the refractive index of the third lens is n3, and the following relational expression is satisfied:

0.5<SAG31*n3<0.8。

preferably, the focal length of the optical imaging system is f, the focal length of the second lens is f2, the focal length of the fifth lens is f5, and the following relations are satisfied:

0.6<|f/f2|+|f/f5|<1.0。

preferably, the radius of curvature of the object-side surface of the second lens element is R21, the radius of curvature of the image-side surface of the fourth lens element is R42, and the following relationships are satisfied:

0.5<R21/R42<1.5。

preferably, the radius of curvature of the image-side surface of the second lens element is R22, the radius of curvature of the object-side surface of the fourth lens element is R41, and the following relationships are satisfied:

1＜R22/R41＜5。

preferably, the central thickness of the fifth lens on the optical axis is CT5, the sum of the central thicknesses of the first lens to the fifth lens on the optical axis is Σ CT, and the following relationship is satisfied:

0.1<CT5/ΣCT<0.16。

preferably, the sum of the refractive indices of the first lens to the fifth lens is ∑ Nd, and the following relational expression is satisfied:

∑Nd≥8.22。

the invention has the beneficial effects that:

1. the infrared imaging and depth perception are realized under the condition of ensuring compact structure, and the advantages of better imaging quality, lower production cost and the like are achieved;

2. by using the lens made of the visible light filtering material, most visible light can be filtered by the lens, so that infrared imaging is clearer, and less visible light interference is caused.

[ description of the drawings ]

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

Fig. 1 is a schematic configuration diagram of an optical imaging system of embodiment 1 of the present invention;

FIG. 2 is a spherical aberration graph of the optical imaging system of example 1;

fig. 3 is a graph of astigmatism and distortion of the optical imaging system of example 1;

FIG. 4 is a graph of chromatic aberration of magnification of the optical imaging system of example 1;

FIG. 5 is a schematic configuration diagram of an optical imaging system of embodiment 2 of the present invention;

FIG. 6 is a spherical aberration graph of the optical imaging system of example 2;

fig. 7 is a graph of astigmatism and distortion for the optical imaging system of example 2;

FIG. 8 is a graph of chromatic aberration of magnification of the optical imaging system of embodiment 2;

fig. 9 is a schematic structural view of an optical imaging system of embodiment 3 of the present invention;

FIG. 10 is a spherical aberration chart of the optical imaging system of example 3;

fig. 11 is a graph of astigmatism and distortion of the optical imaging system of example 3;

FIG. 12 is a graph of chromatic aberration of magnification of the optical imaging system of embodiment 3;

fig. 13 is a schematic configuration diagram of an optical imaging system of embodiment 4 of the present invention;

FIG. 14 is a spherical aberration chart of the optical imaging system of example 4;

fig. 15 is a graph of astigmatism and distortion for the optical imaging system of example 4;

FIG. 16 is a graph of chromatic aberration of magnification of the optical imaging system of example 4;

FIG. 17 is a schematic configuration diagram of an optical imaging system of embodiment 5 of the invention;

FIG. 18 is a spherical aberration chart of the optical imaging system of example 5;

fig. 19 is a graph of astigmatism and distortion for the optical imaging system of example 5;

FIG. 20 is a graph of chromatic aberration of magnification of the optical imaging system of example 5;

FIG. 21 is a schematic configuration diagram of an optical imaging system of embodiment 6 of the present invention;

FIG. 22 is a spherical aberration chart of the optical imaging system of example 6;

fig. 23 is a graph of astigmatism and distortion for the optical imaging system of example 6;

FIG. 24 is a graph of chromatic aberration of magnification of the optical imaging system of example 6;

FIG. 25 is a schematic configuration diagram of an optical imaging system of embodiment 7 of the present invention;

FIG. 26 is a spherical aberration chart of the optical imaging system of example 7;

fig. 27 is a graph of astigmatism and distortion for the optical imaging system of example 7;

fig. 28 is a graph of chromatic aberration of magnification of the optical imaging system of embodiment 7.

[ detailed description ] embodiments

To facilitate an understanding of the invention, the invention will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only and do not represent the only embodiments.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Referring to fig. 1, the present invention provides an optical imaging system including five lenses, in order from an object side to an image side along an optical axis, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, and a fifth lens L5.

The optical imaging system of the present invention may include an optical imaging system including five lenses, that is, the optical imaging system may include the first lens L1 to the fifth lens L5, however, the optical imaging system is not limited to include only five lenses, and may include other components as needed.

Therefore, light rays refracted by external things sequentially pass through the first lens to the fifth lens, then enter the image plane through the optical filter, and are converted into conductive electric signals through the image sensor on the image plane.

Further, the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, and the fifth lens L5 are plastic lenses or glass lenses, wherein the first lens L1 to the fifth lens L5 are five independent lenses, and a space is provided between each two adjacent lenses, that is, each two adjacent lenses are not bonded to each other, but an air space is provided between each two adjacent lenses.

Referring to fig. 1, an optical imaging system includes, in order from an object side to an image side, a first lens element L1, a second lens element L2, a third lens element L3, a fourth lens element L4, and a fifth lens element L5, wherein an object-side surface of the second lens element has at least one inflection point, an object-side surface of the third lens element is concave, a focal length of the third lens element is f3, a distance from a vertical projection point of a maximum effective radius position of an object-side surface of the third lens element on a horizontal optical axis to an intersection point of the object-side surface of the third lens element and the optical axis is SAG31, and satisfies a relation 2< f3/SAG31< 5.

It should be further specifically noted that the optical imaging system includes five lenses L1-L5 in order from the object side to the image side along the optical axis, the first lens L1 has an object side surface S1 and an image side surface S2, the second lens L2 has an object side surface S3 and an image side surface S4, the third lens L3 has an object side surface S5 and an image side surface S6, the fourth lens L4 has an object side surface S7 and an image side surface S8, the fifth lens L5 has an object side surface S9 and an image side surface S10, optionally, the optical imaging system may further include a filter L6 having an object side surface S11 and an image side surface S12, and the filter L6 may be a band pass filter in the imaging optical lens group of the present embodiment, a stop may be further provided to adjust the amount of incoming light, and light from the object passes through the respective surfaces S1-S12 in order and is finally imaged on the imaging surface S13.

Further, the distance from the vertical projection point of the maximum effective radius position of the object side surface of the third lens on the horizontal optical axis to the intersection point of the object side surface of the third lens and the optical axis is SAG31, the refractive index of the third lens is n3, and the following relational expression is satisfied: 0.5< SAG31 × n3< 0.8.

Further, the focal length of the optical imaging system is f, the focal length of the second lens is f2, the focal length of the fifth lens is f5, and the following relations are satisfied: 0.6< | f/f2| + | f/f5| < 1.0.

Further, the radius of curvature of the object-side surface of the second lens is R21, the radius of curvature of the image-side surface of the fourth lens is R42, and the following relation is satisfied: 0.5< R21/R42< 1.5.

Further, the radius of curvature of the image-side surface of the second lens is R22, the radius of curvature of the object-side surface of the fourth lens is R41, and the following relations are satisfied: 1< R22/R41 < 5.

Further, the center thickness of the fifth lens on the optical axis is CT5, the sum of the center thicknesses of the first lens to the fifth lens on the optical axis is Σ CT, and the following relation is satisfied: 0.1< CT5/Σ CT < 0.16.

Further, the sum of the refractive indexes of the first lens to the fifth lens is ∑ Nd, and the following relational expression that ∑ Nd is more than or equal to 8.22 is satisfied.

The optical imaging system according to the above-described embodiment of the present invention may employ a plurality of lenses, for example, five as described above. By reasonably distributing the focal power, the surface type, the on-axis distance between the lenses and the like of each lens, the effective light passing diameter of the optical imaging system can be effectively increased, the miniaturization of a lens is ensured, the imaging quality is improved, and the optical imaging system is more favorable for production and processing. In the embodiment of the present invention, at least one of the mirror surfaces of each lens is an aspherical mirror surface. The aspheric lens is characterized in that: the curvature varies continuously from the center to the periphery of the lens. Unlike a spherical lens having a constant curvature from the center to the periphery of the lens, an aspherical lens has a better curvature radius characteristic, has the advantages of improving distortion aberration and astigmatic aberration, and can make the field of view larger and more realistic. After the aspheric lens is adopted, the aberration generated in imaging can be eliminated as much as possible, so that the imaging quality is improved.

Specific examples of the optical imaging system that can be applied to the above-described embodiments are further described below with reference to the drawings.

Example 1

An optical imaging system according to embodiment 1 of the present invention is described below with reference to fig. 1 to 4. Fig. 1 shows a schematic configuration diagram of an optical imaging system according to embodiment 1 of the present invention.

As shown in fig. 1, the optical imaging system includes five lenses L-L in order from an object side to an image side along an optical axis, the first lens L having an object side surface S1 and an image side surface S2, the second lens L having an object side surface S3 and an image side surface S4, the third lens L having an object side surface S5 and an image side surface S6, the fourth lens L having an object side surface S7 and an image side surface S8, the fifth lens L having an object side surface S9 and an image side surface S10. optionally, the optical imaging system may further include a filter L having an object side surface S11 and an image side surface S12, and the filter L may be a bandpass filter.

Among them, the effective focal length EF L, the full field angle FOV, the total optical length TT L, the aperture Fno, the surface type, the curvature radius, the thickness, the material and the cone coefficient of the optical imaging system of example 1 are shown in table 1:

TABLE 1

As can be seen from table 1, OBJ denotes a light source; the focal length of the optical imaging system is f, the focal length of the second lens is f2, the focal length of the fifth lens is f5, and the following relations are satisfied: 0.6< | f/f2| + | f/f5| <1.0, specifically, | f/f2| + | f/f5| -0.883; the curvature radius of the object side surface of the second lens is R21, the curvature radius of the image side surface of the fourth lens is R42, and the following relational expression is satisfied: 0.5< R21/R42<1.5, specifically, R21/R42 ═ 0.766; the curvature radius of the image side surface of the second lens is R22, the curvature radius of the object side surface of the fourth lens is R41, and the following relational expression is satisfied: 1< R22/R41 <5, specifically, R22/R41 is 3.217.

In the embodiment, five lenses are taken as an example, and the focal power and the surface type of each lens are reasonably distributed, so that the aperture of the lens is effectively enlarged, the total length of the lens is shortened, and the effective light transmission diameter of the lens and the miniaturization of the lens are ensured; meanwhile, various aberrations are corrected, and the resolution and the imaging quality of the lens are improved. Each aspheric surface type x is defined by the following functional relationship:

the aspheric function relationship of the optical imaging system is as follows:

wherein x is the rise of the distance from the aspheric surface vertex to the aspheric surface vertex when the aspheric surface is at the position with the height of h along the optical axis direction; c is the paraxial curvature of the aspheric surface, c being 1/r (i.e., paraxial curvature c is the inverse of radius of curvature r in table 1 above); k is the conic constant (given in table 1 above); ai is a correction coefficient of the i-n th order of the aspherical surface, and the coefficients of the high-order terms A4, A6, A8, A10, A12, A14 and A16 of the respective lens surfaces S1-S10 are shown in Table 2:

TABLE 2

As can be seen from tables 1 and 2, in this embodiment, the focal length of the third lens is f3, the distance between the vertical projection point of the maximum effective radius position of the object-side surface of the third lens on the horizontal optical axis and the intersection point of the object-side surface of the third lens and the optical axis is SAG31, and the following relation is satisfied: 2< f3/SAG31<5, specifically, f3/SAG31 ═ 8.494; the distance from a vertical projection point of the maximum effective radius position of the object side surface of the third lens on a horizontal optical axis to the intersection point of the object side surface of the third lens and the optical axis is SAG31, the refractive index of the third lens is n3, and the following relational expression is satisfied: 0.5< SAG31 × n3<0.8, specifically, SAG31 × n3 ═ 0.614; the center thickness of the fifth lens on the optical axis is CT5, the sum of the center thicknesses of the first lens to the fifth lens on the optical axis is Sigma CT, and the following relation is satisfied: 0.1< CT5/Σ CT <0.16, specifically, CT5/Σ CT is 0.152.

Fig. 2 shows a spherical aberration curve of the optical imaging system of embodiment 1, which shows that light rays of different aperture angles U intersect the optical axis at different points, and have different deviations from the position of an ideal image point. Fig. 3 shows astigmatism curves of the optical imaging system of embodiment 1, which represent meridional field curvature and sagittal field curvature. Fig. 3 shows distortion curves of the optical imaging system of embodiment 1, which represent distortion magnitude values in the case of different viewing angles. Fig. 4 shows a chromatic aberration of magnification curve of the optical imaging system of embodiment 1, which represents the deviation of different image heights on the imaging plane after the light passes through the optical imaging system. As can be seen from fig. 2 to 4, the optical imaging system according to embodiment 1 can achieve good imaging quality.

Example 2

An optical imaging system according to embodiment 2 of the present invention is described below with reference to fig. 5 to 8. Fig. 5 shows a schematic configuration diagram of an optical imaging system according to embodiment 2 of the present invention.

As shown in fig. 5, the optical imaging system includes five lenses L1-L5 in order from the object side to the image side along the optical axis, a first lens L1 having an object side surface S1 and an image side surface S2, a second lens L2 having an object side surface S3 and an image side surface S4, a third lens L3 having an object side surface S5 and an image side surface S6, a fourth lens L4 having an object side surface S7 and an image side surface S8, a fifth lens L5 having an object side surface S9 and an image side surface S10, optionally, the optical imaging system may further include a filter L6 having an object side surface S11 and an image side surface S12, and the filter L6 may be a band pass filter in the optical imaging system of the present embodiment, a stop may be further provided to adjust the amount of incoming light, light from the object sequentially passes through the respective surfaces S1-S12 and is finally imaged on the imaging surface S13.

Among them, the effective focal length EF L, the full field angle FOV, the total optical length TT L, the aperture Fno, the surface type, the curvature radius, the thickness, the material and the cone coefficient of the optical imaging system of example 2 are shown in table 3:

TABLE 3

As can be seen from table 3, OBJ denotes a light source; the focal length of the optical imaging system is f, the focal length of the second lens is f2, the focal length of the fifth lens is f5, and the following relations are satisfied: 0.6< | f/f2| + | f/f5| <1.0, specifically, | f/f2| + | f/f5| -0.887; the curvature radius of the object side surface of the second lens is R21, the curvature radius of the image side surface of the fourth lens is R42, and the following relational expression is satisfied: 0.5< R21/R42<1.5, specifically, R21/R42 is 0.750; the curvature radius of the image side surface of the second lens is R22, the curvature radius of the object side surface of the fourth lens is R41, and the following relational expression is satisfied: 1< R22/R41 <5, specifically, R22/R41 is 3.669.

the aspheric function relationship of the optical imaging system is as follows:

wherein x is the rise of the distance from the aspheric surface vertex to the aspheric surface vertex when the aspheric surface is at the position with the height of h along the optical axis direction; c is the paraxial curvature of the aspheric surface, c being 1/r (i.e., paraxial curvature c is the inverse of radius of curvature r in table 3 above); k is the conic constant (given in table 3 above); ai is a correction coefficient of the i-n th order of the aspherical surface, and the coefficients of the high-order terms a4, a6, A8, a10, a12, a14, and a16 of the respective lens surfaces S1 through S10 are shown in table 4:

TABLE 4

Flour mark

A4

A6

A8

A10

A12

A14

A16

S1

-1.3324864E-01

7.3473285E-02

-8.8938193E-02

9.7369623E-02

-1.0672249E-01

5.8013897E-02

-1.1784980E-02

S2

-1.1243075E-01

-2.1352935E-01

4.5119522E-01

-5.1030068E-01

2.7345437E-01

-6.0775915E-02

1.9631320E-03

S3

3.7617975E-02

-2.2155695E-01

2.7357940E-01

-2.1202034E-01

5.0413287E-02

1.2169037E-02

-4.4477562E-03

S4

-8.6146763E-02

2.0169463E-01

-4.1459174E-01

2.9571988E-01

-8.1217100E-02

6.3539800E-04

2.3247909E-03

S5

-4.4282828E-01

8.5626477E-01

-6.9637956E-01

2.6069840E-01

1.0783788E-02

-4.0519676E-02

8.8763123E-03

S6

2.8835083E-01

-1.7669550E-01

4.2929755E-01

-3.6565616E-01

1.2842616E-01

-1.8073630E-02

5.7281428E-04

S7

-2.0684155E-01

2.9629873E-01

-2.5447159E-01

1.1702087E-01

-9.7856134E-03

-1.3841645E-02

3.6387400E-03

S8

-8.6377988E-01

1.1743081E+00

-8.1714044E-01

3.0838631E-01

-5.3118794E-02

2.4785436E-04

8.1650317E-04

S9

-1.4683363E-01

5.7333505E-01

-5.2574081E-01

1.9462932E-01

-1.3621062E-02

-7.6201042E-03

1.3508407E-03

S10

5.4708287E-01

-4.3160221E-01

1.6026585E-01

-1.5834611E-02

-8.1242414E-03

2.6947910E-03

-2.4199985E-04

As can be seen from tables 3 and 4, in this embodiment, the focal length of the third lens is f3, the distance between the vertical projection point of the maximum effective radius position of the object-side surface of the third lens on the horizontal optical axis and the intersection point of the object-side surface of the third lens and the optical axis is SAG31, and the following relationship is satisfied: 2< f3/SAG31<5, specifically, f3/SAG31 ═ 9.801; the distance from a vertical projection point of the maximum effective radius position of the object side surface of the third lens on a horizontal optical axis to the intersection point of the object side surface of the third lens and the optical axis is SAG31, the refractive index of the third lens is n3, and the following relational expression is satisfied: 0.5< SAG31 × n3<0.8, specifically, SAG31 × n3 ═ 0.601; the center thickness of the fifth lens on the optical axis is CT5, the sum of the center thicknesses of the first lens to the fifth lens on the optical axis is Sigma CT, and the following relation is satisfied: 0.1< CT5/Σ CT <0.16, specifically, CT5/Σ CT is 0.115.

Fig. 6 shows a spherical aberration curve of the optical imaging system of embodiment 2, which shows that light rays of different aperture angles U intersect the optical axis at different points, and have different deviations from the position of an ideal image point. Fig. 7 shows astigmatism curves of the optical imaging system of embodiment 2, which represent meridional field curvature and sagittal field curvature. Fig. 7 shows distortion curves of the optical imaging system of embodiment 2, which represent distortion magnitude values in the case of different viewing angles. Fig. 8 shows a chromatic aberration of magnification curve of the optical imaging system of embodiment 2, which represents the deviation of different image heights on the imaging plane after the light passes through the optical imaging system. As can be seen from fig. 6 to 8, the optical imaging system according to embodiment 2 can achieve good imaging quality.

Example 3

An optical imaging system according to embodiment 3 of the present invention is described below with reference to fig. 9 to 12. Fig. 9 shows a schematic configuration diagram of an optical imaging system according to embodiment 3 of the present invention.

As shown in fig. 9, the optical imaging system includes five lenses L1-L5 in order from an object side to an image side along an optical axis, a first lens L1 having an object side surface S1 and an image side surface S2, a second lens L2 having an object side surface S3 and an image side surface S4, a third lens L3 having an object side surface S5 and an image side surface S6, a fourth lens L4 having an object side surface S7 and an image side surface S8, a fifth lens L5 having an object side surface S9 and an image side surface S10, optionally, the optical imaging system may further include a filter L6 having an object side surface S11 and an image side surface S12, and the filter L6 may be a band pass filter in the optical imaging system of the present embodiment, a stop may be further provided to adjust an amount of incoming light, light from an object sequentially passes through the respective surfaces S1-S12 and is finally imaged on the imaging surface S13.

Among them, the effective focal length EF L, the full field angle FOV, the total optical length TT L, the aperture Fno, the surface type, the curvature radius, the thickness, the material and the cone coefficient of the optical imaging system of example 3 are shown in table 5:

TABLE 5

As can be seen from table 5, OBJ denotes a light source; the focal length of the optical imaging system is f, the focal length of the second lens is f2, the focal length of the fifth lens is f5, and the following relations are satisfied: 0.6< | f/f2| + | f/f5| <1.0, specifically, | f/f2| + | f/f5| -0.804; the curvature radius of the object side surface of the second lens is R21, the curvature radius of the image side surface of the fourth lens is R42, and the following relational expression is satisfied: 0.5< R21/R42<1.5, specifically, R21/R42 ═ 0.856; the curvature radius of the image side surface of the second lens is R22, the curvature radius of the object side surface of the fourth lens is R41, and the following relational expression is satisfied: 1< R22/R41 <5, specifically, R22/R41 is 3.221.

the aspheric function relationship of the optical imaging system is as follows:

wherein x is the rise of the distance from the aspheric surface vertex to the aspheric surface vertex when the aspheric surface is at the position with the height of h along the optical axis direction; c is the paraxial curvature of the aspheric surface, c being 1/r (i.e., paraxial curvature c is the inverse of radius of curvature r in table 5 above); k is the conic constant (given in table 5 above); ai is a correction coefficient of the i-n th order of the aspherical surface, and the coefficients of the high-order terms a4, a6, A8, a10, a12, a14, and a16 of the respective lens surfaces S1 through S10 are shown in table 6:

TABLE 6

Flour mark

A4

A6

A8

A10

A12

A14

A16

S1

-1.3699302E-01

7.0460213E-02

-9.0348268E-02

9.7690506E-02

-1.0607463E-01

5.8248844E-02

-1.1867994E-02

S2

-1.1199745E-01

-2.1573157E-01

4.5066854E-01

-5.0918413E-01

2.7443809E-01

-6.0514224E-02

1.6510136E-03

S3

3.8089185E-02

-2.1789578E-01

2.7710688E-01

-2.1029778E-01

5.0854660E-02

1.2008532E-02

-4.8231757E-03

S4

-8.1580064E-02

2.0009969E-01

-4.1828654E-01

2.9500123E-01

-8.0920393E-02

9.2855457E-04

2.4668703E-03

S5

-4.6327242E-01

8.4808919E-01

-6.9837841E-01

2.6005666E-01

1.0707515E-02

-4.0392063E-02

9.0155219E-03

S6

2.8596425E-01

-1.8300391E-01

4.2896099E-01

-3.6511349E-01

1.2864589E-01

-1.8073108E-02

5.2184978E-04

S7

-2.0801726E-01

2.9615946E-01

-2.5389017E-01

1.1749099E-01

-9.6107552E-03

-1.3823280E-02

3.6198696E-03

S8

-8.7828569E-01

1.1740090E+00

-8.1580570E-01

3.0859251E-01

-5.3179556E-02

2.4633557E-04

8.3295787E-04

S9

-1.3797248E-01

5.6906028E-01

-5.2645570E-01

1.9457860E-01

-1.3731843E-02

-7.6718830E-03

1.3511862E-03

S10

5.5438954E-01

-4.3102816E-01

1.5876815E-01

-1.6064009E-02

-7.9676636E-03

2.7377827E-03

-2.5468837E-04

As can be seen from tables 5 and 6, in this embodiment, the focal length of the third lens is f3, the distance between the perpendicular projection point of the maximum effective radius position of the object-side surface of the third lens on the horizontal optical axis and the intersection point of the object-side surface of the third lens and the optical axis is SAG31, and the following relationship is satisfied: 2< f3/SAG31<5, specifically, f3/SAG31 ═ 6.283; the distance from a vertical projection point of the maximum effective radius position of the object side surface of the third lens on a horizontal optical axis to the intersection point of the object side surface of the third lens and the optical axis is SAG31, the refractive index of the third lens is n3, and the following relational expression is satisfied: 0.5< SAG31 × n3<0.8, specifically, SAG31 × n3 ═ 0.737; the center thickness of the fifth lens on the optical axis is CT5, the sum of the center thicknesses of the first lens to the fifth lens on the optical axis is Sigma CT, and the following relation is satisfied: 0.1< CT5/Σ CT <0.16, specifically, CT5/Σ CT is 0.150.

Fig. 10 shows a spherical aberration curve of the optical imaging system of embodiment 3, which shows that light rays of different aperture angles U intersect the optical axis at different points, and have different deviations from the position of an ideal image point. Fig. 11 shows astigmatism curves of the optical imaging system of embodiment 3, which represent meridional field curvature and sagittal field curvature. Fig. 11 shows distortion curves of the optical imaging system of embodiment 3, which represent distortion magnitude values in the case of different viewing angles. Fig. 12 shows a chromatic aberration of magnification curve of the optical imaging system of example 3, which represents the deviation of different image heights on the imaging plane after the light passes through the optical imaging system. As can be seen from fig. 10 to 12, the optical imaging system according to embodiment 3 can achieve good imaging quality.

Example 4

An optical imaging system according to embodiment 1 of the present invention is described below with reference to fig. 13 to 16. Fig. 13 shows a schematic configuration diagram of an optical imaging system according to embodiment 4 of the present invention.

As shown in fig. 13, the optical imaging system includes five lenses L1-L5 in order from the object side to the image side along the optical axis, a first lens L1 having an object side surface S1 and an image side surface S2, a second lens L2 having an object side surface S3 and an image side surface S4, a third lens L3 having an object side surface S5 and an image side surface S6, a fourth lens L4 having an object side surface S7 and an image side surface S8, a fifth lens L5 having an object side surface S9 and an image side surface S10, optionally, the optical imaging system may further include a filter L6 having an object side surface S11 and an image side surface S12, and the filter L6 may be a band pass filter in the optical imaging system of the present embodiment, a stop may be further provided to adjust the amount of incoming light, light from the object sequentially passes through the respective surfaces S1-S12 and is finally imaged on the imaging surface S13.

Among them, the effective focal length EF L, the full field angle FOV, the total optical length TT L, the aperture Fno, the surface type, the curvature radius, the thickness, the material and the cone coefficient of the optical imaging system of example 4 are shown in table 7:

TABLE 7

As can be seen from table 7, OBJ denotes a light source; the focal length of the optical imaging system is f, the focal length of the second lens is f2, the focal length of the fifth lens is f5, and the following relations are satisfied: 0.6< | f/f2| + | f/f5| <1.0, specifically, | f/f2| + | f/f5| -0.789; the curvature radius of the object side surface of the second lens is R21, the curvature radius of the image side surface of the fourth lens is R42, and the following relational expression is satisfied: 0.5< R21/R42<1.5, specifically, R21/R42 ═ 0.819; the curvature radius of the image side surface of the second lens is R22, the curvature radius of the object side surface of the fourth lens is R41, and the following relational expression is satisfied: 1< R22/R41 <5, specifically, R22/R41 is 3.589.

the aspheric function relationship of the optical imaging system is as follows:

wherein x is the rise of the distance from the aspheric surface vertex to the aspheric surface vertex when the aspheric surface is at the position with the height of h along the optical axis direction; c is the paraxial curvature of the aspheric surface, c being 1/r (i.e., paraxial curvature c is the inverse of radius of curvature r in table 7 above); k is the conic constant (given in table 7 above); ai is a correction coefficient of the i-n th order of the aspherical surface, and the coefficients of the high-order terms a4, a6, A8, a10, a12, a14, and a16 of the respective lens surfaces S1 through S10 are shown in table 8:

TABLE 8

As can be seen from tables 7 and 8, in this embodiment, the focal length of the third lens is f3, the distance between the perpendicular projection point of the maximum effective radius position of the object-side surface of the third lens on the horizontal optical axis and the intersection point of the object-side surface of the third lens and the optical axis is SAG31, and the following relation is satisfied: 2< f3/SAG31<5, specifically, f3/SAG31 ═ 6.783; the distance from a vertical projection point of the maximum effective radius position of the object side surface of the third lens on a horizontal optical axis to the intersection point of the object side surface of the third lens and the optical axis is SAG31, the refractive index of the third lens is n3, and the following relational expression is satisfied: 0.5< SAG31 × n3<0.8, specifically, SAG31 × n3 ═ 0.797; the center thickness of the fifth lens on the optical axis is CT5, the sum of the center thicknesses of the first lens to the fifth lens on the optical axis is Sigma CT, and the following relation is satisfied: 0.1< CT5/Σ CT <0.16, specifically, CT5/Σ CT is 0.136.

Fig. 14 shows a spherical aberration curve of the optical imaging system of embodiment 4, which shows that light rays of different aperture angles U intersect the optical axis at different points, and have different deviations from the position of an ideal image point. Fig. 15 shows astigmatism curves of the optical imaging system of embodiment 4, which represent meridional field curvature and sagittal field curvature. Fig. 15 shows distortion curves of the optical imaging system of example 4, which represent distortion magnitude values in the case of different viewing angles. Fig. 16 shows a chromatic aberration of magnification curve of the optical imaging system of example 4, which represents the deviation of different image heights on the imaging plane after the light passes through the optical imaging system. As can be seen from fig. 14 to 16, the optical imaging system according to embodiment 4 can achieve good imaging quality.

Example 5

An optical imaging system according to embodiment 5 of the present invention is described below with reference to fig. 17 to 20. Fig. 17 is a schematic structural view showing an optical imaging system according to embodiment 5 of the present invention.

As shown in fig. 17, the optical imaging system includes five lenses L1-L5 in order from an object side to an image side along an optical axis, a first lens L1 having an object side surface S1 and an image side surface S2, a second lens L2 having an object side surface S3 and an image side surface S4, a third lens L3 having an object side surface S5 and an image side surface S6, a fourth lens L4 having an object side surface S7 and an image side surface S8, a fifth lens L5 having an object side surface S9 and an image side surface S10, optionally, the optical imaging system may further include a filter L6 having an object side surface S11 and an image side surface S12, and the filter L6 may be a band pass filter in the optical imaging system of the present embodiment, a stop may be further provided to adjust an amount of incoming light, light from an object sequentially passes through the respective surfaces S1-S12 and is finally imaged on the imaging surface S13.

Among them, the effective focal length EF L, the full field angle FOV, the total optical length TT L, the aperture Fno, the surface type, the curvature radius, the thickness, the material and the cone coefficient of the optical imaging system of example 5 are shown in table 9:

TABLE 9

As can be seen from table 9, OBJ denotes a light source; the focal length of the optical imaging system is f, the focal length of the second lens is f2, the focal length of the fifth lens is f5, and the following relations are satisfied: 0.6< | f/f2| + | f/f5| <1.0, specifically, | f/f2| + | f/f5| -0.986; the curvature radius of the object side surface of the second lens is R21, the curvature radius of the image side surface of the fourth lens is R42, and the following relational expression is satisfied: 0.5< R21/R42<1.5, specifically, R21/R42 ═ 0.721; the curvature radius of the image side surface of the second lens is R22, the curvature radius of the object side surface of the fourth lens is R41, and the following relational expression is satisfied: 1< R22/R41 <5, specifically, R22/R41 is 3.536.

the aspheric function relationship of the optical imaging system is as follows:

wherein x is the rise of the distance from the aspheric surface vertex to the aspheric surface vertex when the aspheric surface is at the position with the height of h along the optical axis direction; c is the paraxial curvature of the aspheric surface, c being 1/r (i.e., paraxial curvature c is the inverse of radius of curvature r in table 9 above); k is the conic constant (given in table 9 above); ai is a correction coefficient of the i-n th order of the aspherical surface, and the coefficients of the high-order terms a4, a6, A8, a10, a12, a14, and a16 of the respective lens surfaces S1 through S10 are shown in table 10:

watch 10

Flour mark

A4

A6

A8

A10

A12

A14

A16

S1

-1.3307347E-01

7.3096289E-02

-8.9507082E-02

9.7026703E-02

-1.0678826E-01

5.8020952E-02

-1.1797017E-02

S2

-1.1265975E-01

-2.1328721E-01

4.5095725E-01

-5.1088088E-01

2.7311472E-01

-6.0837696E-02

2.0950765E-03

S3

3.8008509E-02

-2.2218430E-01

2.7335769E-01

-2.1202174E-01

5.0429666E-02

1.2189178E-02

-4.4480838E-03

S4

-8.6513650E-02

2.0110763E-01

-4.1456923E-01

2.9576365E-01

-8.1201935E-02

6.3787815E-04

2.3231715E-03

S5

-4.4529553E-01

8.5471736E-01

-6.9714779E-01

2.6047955E-01

1.0731725E-02

-4.0527033E-02

8.8767959E-03

S6

2.8611004E-01

-1.7788995E-01

4.2930948E-01

-3.6565225E-01

1.2841513E-01

-1.8082746E-02

5.6972398E-04

S7

-2.0554418E-01

2.9766777E-01

-2.5422640E-01

1.1706026E-01

-9.7491857E-03

-1.3803594E-02

3.6693240E-03

S8

-8.7164621E-01

1.1761553E+00

-8.1656266E-01

3.0843158E-01

-5.3126088E-02

2.4599473E-04

8.2046925E-04

S9

-1.3530092E-01

5.6944206E-01

-5.2544861E-01

1.9500201E-01

-1.3486780E-02

-7.6026921E-03

1.3403877E-03

S10

5.2643773E-01

-4.2412718E-01

1.6025317E-01

-1.6011967E-02

-8.1486799E-03

2.6979858E-03

-2.3660313E-04

As can be seen from tables 9 and 10, in this embodiment, the focal length of the third lens is f3, the distance between the perpendicular projection point of the maximum effective radius position of the object-side surface of the third lens on the horizontal optical axis and the intersection point of the object-side surface of the third lens and the optical axis is SAG31, and the following relationship is satisfied: 2< f3/SAG31<5, specifically, f3/SAG31 ═ 8.490; the distance from a vertical projection point of the maximum effective radius position of the object side surface of the third lens on a horizontal optical axis to the intersection point of the object side surface of the third lens and the optical axis is SAG31, the refractive index of the third lens is n3, and the following relational expression is satisfied: 0.5< SAG31 × n3<0.8, specifically, SAG31 × n3 ═ 0.616; the center thickness of the fifth lens on the optical axis is CT5, the sum of the center thicknesses of the first lens to the fifth lens on the optical axis is Sigma CT, and the following relation is satisfied: 0.1< CT5/Σ CT <0.16, specifically, CT5/Σ CT is 0.113.

Fig. 18 shows a spherical aberration curve of the optical imaging system of example 5, which shows that light rays of different aperture angles U intersect the optical axis at different points, with different deviations from the position of an ideal image point. Fig. 19 shows astigmatism curves of the optical imaging system of embodiment 5, which represent meridional field curvature and sagittal field curvature. Fig. 19 shows distortion curves of the optical imaging system of example 5, which represent distortion magnitude values in the case of different viewing angles. Fig. 20 shows a chromatic aberration of magnification curve of the optical imaging system of example 5, which represents the deviation of different image heights on the imaging plane after the light passes through the optical imaging system. As can be seen from fig. 18 to 20, the optical imaging system according to embodiment 5 can achieve good imaging quality.

Example 6

An optical imaging system according to embodiment 6 of the present invention is described below with reference to fig. 21 to 24. Fig. 21 is a schematic structural view showing an optical imaging system according to embodiment 6 of the present invention.

As shown in fig. 21, the optical imaging system includes five lenses L1-L5 in order from the object side to the image side along the optical axis, a first lens L1 having an object side surface S1 and an image side surface S2, a second lens L2 having an object side surface S3 and an image side surface S4, a third lens L3 having an object side surface S5 and an image side surface S6, a fourth lens L4 having an object side surface S7 and an image side surface S8, a fifth lens L5 having an object side surface S9 and an image side surface S10, optionally, the optical imaging system may further include a filter L6 having an object side surface S11 and an image side surface S12, and the filter L6 may be a band pass filter in the optical imaging system of the present embodiment, a stop may be further provided to adjust the amount of incoming light, light from the object sequentially passes through the respective surfaces S1-S12 and is finally imaged on the imaging surface S13.

Among them, the effective focal length EF L, the full field angle FOV, the total optical length TT L, the aperture Fno, the surface type, the curvature radius, the thickness, the material and the cone coefficient of the optical imaging system of example 1 are shown in table 11:

TABLE 11

As can be seen from table 11, OBJ denotes a light source; the focal length of the optical imaging system is f, the focal length of the second lens is f2, the focal length of the fifth lens is f5, and the following relations are satisfied: 0.6< | f/f2| + | f/f5| <1.0, specifically, | f/f2| + | f/f5| -0.614; the curvature radius of the object side surface of the second lens is R21, the curvature radius of the image side surface of the fourth lens is R42, and the following relational expression is satisfied: 0.5< R21/R42<1.5, specifically, R21/R42 ═ 0.890; the curvature radius of the image side surface of the second lens is R22, the curvature radius of the object side surface of the fourth lens is R41, and the following relational expression is satisfied: 1< R22/R41 <5, specifically, R22/R41 is 3.455.

the aspheric function relationship of the optical imaging system is as follows:

wherein x is the rise of the distance from the aspheric surface vertex to the aspheric surface vertex when the aspheric surface is at the position with the height of h along the optical axis direction; c is the paraxial curvature of the aspheric surface, c being 1/r (i.e., paraxial curvature c is the inverse of radius of curvature r in table 11 above); k is the conic constant (given in table 11 above); ai is a correction coefficient of the i-n th order of the aspherical surface, and the coefficients of the high-order terms a4, a6, A8, a10, a12, a14, and a16 of the respective lens surfaces S1 through S10 are shown in table 12:

TABLE 12

Flour mark

A4

A6

A8

A10

A12

A14

A16

S1

-1.3644751E-01

7.2370048E-02

-8.9220672E-02

9.7422697E-02

-1.0670628E-01

5.8092146E-02

-1.1865342E-02

S2

-1.0852994E-01

-2.1520281E-01

4.5022009E-01

-5.1015307E-01

2.7395550E-01

-6.0507362E-02

1.6670699E-03

S3

3.6794671E-02

-2.1834929E-01

2.7605831E-01

-2.1148685E-01

5.0736611E-02

1.2187617E-02

-4.5481321E-03

S4

-8.3013162E-02

2.0249076E-01

-4.1532690E-01

2.9553343E-01

-8.0996948E-02

7.0483067E-04

2.3585518E-03

S5

-4.4933194E-01

8.5418855E-01

-6.9703834E-01

2.6050327E-01

1.0827813E-02

-4.0506176E-02

8.9373299E-03

S6

2.8339843E-01

-1.7576911E-01

4.2987677E-01

-3.6557731E-01

1.2843057E-01

-1.8078044E-02

5.4674881E-04

S7

-2.0454126E-01

2.9420369E-01

-2.5519491E-01

1.1735905E-01

-9.5804214E-03

-1.3716148E-02

3.6657856E-03

S8

-8.7328019E-01

1.1742850E+00

-8.1607970E-01

3.0856578E-01

-5.3095494E-02

2.4043460E-04

8.1220580E-04

S9

-1.4879917E-01

5.8499553E-01

-5.2812314E-01

1.9440090E-01

-1.3709047E-02

-7.7297247E-03

1.3063256E-03

S10

5.8980185E-01

-4.4405664E-01

1.6070769E-01

-1.5468777E-02

-8.0327456E-03

2.6931478E-03

-2.5224949E-04

As can be seen from tables 11 and 12, in this embodiment, the focal length of the third lens is f3, the distance between the perpendicular projection point of the maximum effective radius position of the object-side surface of the third lens on the horizontal optical axis and the intersection point of the object-side surface of the third lens and the optical axis is SAG31, and the following relationship is satisfied: 2< f3/SAG31<5, specifically, f3/SAG31 ═ 7.974; the distance from a vertical projection point of the maximum effective radius position of the object side surface of the third lens on a horizontal optical axis to the intersection point of the object side surface of the third lens and the optical axis is SAG31, the refractive index of the third lens is n3, and the following relational expression is satisfied: 0.5< SAG31 × n3<0.8, specifically, SAG31 × n3 ═ 0.631; the center thickness of the fifth lens on the optical axis is CT5, the sum of the center thicknesses of the first lens to the fifth lens on the optical axis is Sigma CT, and the following relation is satisfied: 0.1< CT5/Σ CT <0.16, specifically, CT5/Σ CT is 0.139.

Fig. 22 shows a spherical aberration curve of the optical imaging system of example 6, which shows that light rays of different aperture angles U intersect the optical axis at different points, and have different deviations from the position of an ideal image point. Fig. 23 shows astigmatism curves of the optical imaging system of embodiment 1, which represent meridional field curvature and sagittal field curvature. Fig. 23 shows distortion curves of the optical imaging system of embodiment 1, which represent distortion magnitude values in the case of different viewing angles. Fig. 24 shows a chromatic aberration of magnification curve of the optical imaging system of embodiment 1, which represents the deviation of different image heights on the imaging plane after the light passes through the optical imaging system. As can be seen from fig. 22 to 24, the optical imaging system according to embodiment 6 can achieve good imaging quality.

Example 7

An optical imaging system according to embodiment 7 of the present invention is described below with reference to fig. 25 to 28. Fig. 25 shows a schematic configuration diagram of an optical imaging system according to embodiment 7 of the present invention.

As shown in fig. 25, the optical imaging system includes five lenses L1-L5 in order from the object side to the image side along the optical axis, a first lens L1 having an object side surface S1 and an image side surface S2, a second lens L2 having an object side surface S3 and an image side surface S4, a third lens L3 having an object side surface S5 and an image side surface S6, a fourth lens L4 having an object side surface S7 and an image side surface S8, a fifth lens L5 having an object side surface S9 and an image side surface S10, optionally, the optical imaging system may further include a filter L6 having an object side surface S11 and an image side surface S12, and the filter L6 may be a band pass filter in the optical imaging system of the present embodiment, a stop may be further provided to adjust the amount of incoming light, light from the object sequentially passes through the respective surfaces S1-S12 and is finally imaged on the imaging surface S13.

Among them, the effective focal length EF L, the full field angle FOV, the total optical length TT L, the aperture Fno, the surface type, the curvature radius, the thickness, the material and the cone coefficient of the optical imaging system of example 7 are shown in table 13:

watch 13

As can be seen from table 13, OBJ denotes a light source; the focal length of the optical imaging system is f, the focal length of the second lens is f2, the focal length of the fifth lens is f5, and the following relations are satisfied: 0.6< | f/f2| + | f/f5| <1.0, specifically, | f/f2| + | f/f5| -0.687; the curvature radius of the object side surface of the second lens is R21, the curvature radius of the image side surface of the fourth lens is R42, and the following relational expression is satisfied: 0.5< R21/R42<1.5, specifically, R21/R42 ═ 1.127; the curvature radius of the image side surface of the second lens is R22, the curvature radius of the object side surface of the fourth lens is R41, and the following relational expression is satisfied: 1< R22/R41 <5, specifically, R22/R41 is 4.193.

the aspheric function relationship of the optical imaging system is as follows:

wherein x is the rise of the distance from the aspheric surface vertex to the aspheric surface vertex when the aspheric surface is at the position with the height of h along the optical axis direction; c is the paraxial curvature of the aspheric surface, c being 1/r (i.e., paraxial curvature c is the inverse of radius of curvature r in table 13 above); k is the conic constant (given in table 13 above); ai is a correction coefficient of the i-n th order of the aspherical surface, and the coefficients of the high-order terms a4, a6, A8, a10, a12, a14, and a16 of the respective lens surfaces S1 through S10 are shown in table 14:

TABLE 14

As can be seen from tables 13 and 14, in this embodiment, the focal length of the third lens is f3, the distance between the perpendicular projection point of the maximum effective radius position of the object-side surface of the third lens on the horizontal optical axis and the intersection point of the object-side surface of the third lens and the optical axis is SAG31, and the following relationship is satisfied: 2< f3/SAG31<5, specifically, f3/SAG31 ═ 7.881; the distance from a vertical projection point of the maximum effective radius position of the object side surface of the third lens on a horizontal optical axis to the intersection point of the object side surface of the third lens and the optical axis is SAG31, the refractive index of the third lens is n3, and the following relational expression is satisfied: 0.5< SAG31 × n3<0.8, specifically, SAG31 × n3 ═ 0.641; the center thickness of the fifth lens on the optical axis is CT5, the sum of the center thicknesses of the first lens to the fifth lens on the optical axis is Sigma CT, and the following relation is satisfied: 0.1< CT5/Σ CT <0.16, specifically, CT5/Σ CT is 0.156.

Fig. 26 shows a spherical aberration curve of the optical imaging system of example 7, which shows that light rays of different aperture angles U intersect the optical axis at different points, with different deviations from the position of an ideal image point. Fig. 27 shows astigmatism curves of the optical imaging system of embodiment 7, which represent meridional field curvature and sagittal field curvature. Fig. 27 shows distortion curves of the optical imaging system of example 7, which represent distortion magnitude values in the case of different viewing angles. Fig. 28 shows a chromatic aberration of magnification curve of the optical imaging system of example 7, which represents the deviation of different image heights on the imaging plane after the light passes through the optical imaging system. As can be seen from fig. 26 to 28, the optical imaging system according to embodiment 7 can achieve good imaging quality.

The invention has the beneficial effects that:

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above embodiments only express a few embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. An optical imaging system, in order from an object side to an image side, comprising:

a first lens, a second lens, a third lens, a fourth lens and a fifth lens;

2<f3/SAG31<5。

2. the optical imaging system of claim 1, wherein the distance between the vertical projection point of the maximum effective radius position of the object-side surface of the third lens on the horizontal optical axis and the intersection point of the object-side surface and the optical axis is SAG31, the refractive index of the third lens is n3, and the following relation is satisfied:

0.5<SAG31*n3<0.8。

3. the optical imaging system of claim 1, wherein the optical imaging system has a focal length f, the second lens has a focal length f2, the fifth lens has a focal length f5, and the following relationships are satisfied:

0.6<|f/f2|+|f/f5|<1.0。

4. the optical imaging system of claim 1, wherein the radius of curvature of the object-side surface of the second lens element is R21, the radius of curvature of the image-side surface of the fourth lens element is R42, and the following relationships are satisfied:

0.5<R21/R42<1.5。

5. the optical imaging system of claim 1, wherein the radius of curvature of the image-side surface of the second lens element is R22, the radius of curvature of the object-side surface of the fourth lens element is R41, and the following relationships are satisfied:

1＜R22/R41＜5。

6. the optical imaging system of claim 1, wherein the central thickness of the fifth lens on the optical axis is CT5, the sum of the central thicknesses of the first to fifth lenses on the optical axis is Σ CT, and the following relationship is satisfied:

0.1<CT5/ΣCT<0.16。

7. the optical imaging system according to claim 1, wherein the sum of the refractive indices of the first lens to the fifth lens is ∑ Nd, and the following relation is satisfied:

∑Nd≥8.22。