CN109031588A

CN109031588A - Optical lens

Info

Publication number: CN109031588A
Application number: CN201710438657.XA
Authority: CN
Inventors: 姚波; 王东方; 张野
Original assignee: Ningbo Sunny Opotech Co Ltd
Current assignee: Ningbo Sunny Opotech Co Ltd
Priority date: 2017-06-12
Filing date: 2017-06-12
Publication date: 2018-12-18
Anticipated expiration: 2037-06-12
Also published as: CN109031588B

Abstract

This application discloses a kind of optical lens, which sequentially includes: the first lens, the second lens, the third lens and the 4th lens by object side to image side along optical axis.Wherein, the first lens have negative power, and object side is convex surface, and image side surface is concave surface；Second lens have positive light coke, and object side and image side surface are convex surface；The third lens have negative power；And the 4th lens have positive light coke, object side be convex surface, image side surface is concave surface.

Description

Optical lens

Technical field

This application involves a kind of optical lens, more specifically, this application involves a kind of optical lens including four lens.

Background technique

Commonly used with camera, the type of optional chip is more and more.Part special chip is setting clocking requirement The angle CRA (chief ray angle) of chief ray incident chip reach 25 ° or so, exceed custom requirements.The key light of general camera lens Line angle CRA can not this numerical value, cause camera lens that can not match with chip, to situations such as color difference occur.

Meanwhile application conditional for certain installation sites, it is also necessary to which camera lens has lesser rear end size.Such as it needs On-vehicle lens in the car are installed, due to being restricted in installation place, and need to come simultaneously using special lens design Meet the requirement that rear end size is small and chief ray angle CRA is big.

Accordingly, it is desirable to provide the optical lens that a kind of chief ray angle CRA is big, rear end size is small and resolving power is high.

Summary of the invention

Technical solution provided by the present application at least has been partially solved techniques discussed above problem.

Disclose such a optical lens according to the one aspect of the application, the optical lens along optical axis by object side extremely Image side sequentially includes: the first lens, the second lens, the third lens and the 4th lens.Wherein, the first lens can have negative light focus Degree, object side can be convex surface, and image side surface can be concave surface；Second lens can have positive light coke, and object side and image side surface are equal It can be convex surface；The third lens can have negative power；And the 4th lens can have a positive light coke, object side can be convex surface, Image side surface can be concave surface.

In one embodiment, above-mentioned optical lens further includes a diaphragm, which can be located at the second lens and third Between lens.

In one embodiment, distance T on the object side to the axis of diaphragm of the first lens_BeforeWith diaphragm to optical lens Distance T on the axis of imaging surface_AfterwardsBetween can meet T_Before/T_Afterwards≥1.5。

Such a optical lens is also disclosed according to further aspect of the application, the optical lens is along optical axis by object Side to image side sequentially includes: the first lens, the second lens, diaphragm and at least one subsequent lens.Wherein, the first lens can have There is negative power, object side can be convex surface, and image side surface can be concave surface；Second lens can have a positive light coke, object side and Image side surface can be convex surface；And first lens object side to the axis of diaphragm on distance T_BeforeWith the imaging of diaphragm to optical lens Distance T on the axis in face_AfterwardsBetween can meet T_Before/T_Afterwards≥1.5。

In one embodiment, at least one subsequent lens of above-mentioned optical lens can include: the third lens can have Negative power；And the 4th lens, there can be positive light coke, object side can be convex surface, and image side surface can be concave surface.

In one embodiment, the image side surface of the third lens can be concave surface, and object side can be convex surface.

In one embodiment, the object side of the third lens and image side surface can be concave surface.

In one embodiment, the third lens and the glue-bondable composition balsaming lens of the 4th lens.

In one embodiment, at least a piece of lens are non-spherical lens in the second lens and the 4th lens.

In one embodiment, can meet between the focal length value f1 of the first lens and the total focal length value f of optical lens- 3.0≤f1/f≤-1.5。

In one embodiment, f2/ can be met between the focal length value f2 of the second lens and the total focal length value f of optical lens f≥0.9。

In one embodiment, the spacing distance T12 and optical lens of the first lens and the second lens on optical axis T12/f >=1.5 can be met between total focal length value f.

In one embodiment, the total focal length value f of the radius of curvature R 4i of the image side surface of the 4th lens and optical lens it Between can meet R4i/f >=1.3.

In one embodiment, the maximum clear aperture D4i of the 4th lens image side surface corresponding to maximum field of view angle, most D4i/h/FOV≤0.01 can be met between image height h and maximum field of view angle FOV corresponding to big field angle.

The application uses multi-disc (for example, four) lens, by between the arrangement of reasonable eyeglass, focal power distribution, eyeglass Airspace distribution and the 4th concave lens surface towards image side bent moon eyeglass design so that optical lens guarantee great achievement While as size and high pixel, have it is following at least one the utility model has the advantages that

Under identical imaging surface, increase chief ray angle CRA；

Reduce the rear end size of camera lens；And

Improve the resolution and image quality of camera lens.

Detailed description of the invention

In conjunction with attached drawing, by the detailed description of following non-limiting embodiment, other features of the invention, purpose and excellent Point will be apparent.In the accompanying drawings:

Fig. 1 is the structural schematic diagram for showing the optical lens according to the embodiment of the present application 1；

Fig. 2 is the structural schematic diagram for showing the optical lens according to the embodiment of the present application 2.

Specific embodiment

Various aspects of the reference attached drawing to the application are made more detailed description by the application in order to better understand.It answers Understand, the only description to the illustrative embodiments of the application is described in detail in these, rather than limits the application in any way Range.In the specification, the identical element of identical reference numbers.Stating "and/or" includes associated institute Any and all combinations of one or more of list of items.

It should be noted that in the present specification, first, second, third, etc. statement is only used for a feature and another spy Sign distinguishes, without indicating any restrictions to feature.Therefore, without departing substantially from teachings of the present application, hereinafter The first lens discussed are also known as the second lens or the third lens.

In the accompanying drawings, for ease of description, thickness, the size and shape of lens are slightly exaggerated.Specifically, attached drawing Shown in spherical surface or aspherical shape be illustrated by way of example.That is, spherical surface or aspherical shape are not limited to attached drawing Shown in spherical surface or aspherical shape.Attached drawing is merely illustrative and and non-critical drawn to scale.

In addition, near axis area refers to the region near optical axis.Herein, claim in each lens near the surface of object For object side, it is known as image side surface near the surface of imaging surface in each lens.

It will also be appreciated that term " comprising ", " including ", " having ", "comprising" and/or " including ", when in this theory In bright book use when indicate exist stated feature, entirety, step, operations, elements, and/or components, but do not exclude the presence of or It is attached with one or more of the other feature, entirety, step, operation, component, assembly unit and/or their combination.In addition, ought be such as When the statement of at least one of " ... " appears in after the list of listed feature, entire listed feature is modified, rather than is modified Individual component in list.In addition, when describing presently filed embodiment, use " can with " indicate " one of the application or Multiple embodiments ".Also, term " illustrative " is intended to refer to example or illustration.

Unless otherwise defined, otherwise all terms (including technical terms and scientific words) used herein all have with The application one skilled in the art's is generally understood identical meaning.It will also be appreciated that term (such as in everyday words Term defined in allusion quotation) it should be interpreted as having and their consistent meanings of meaning in the context of the relevant technologies, and It will not be explained with idealization or excessively formal sense, unless clear herein so limit.

It should be noted that in the absence of conflict, the features in the embodiments and the embodiments of the present application can phase Mutually combination.The application is described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

The feature of the application, principle and other aspects are described in detail below.

Optical lens according to the application illustrative embodiments may include such as four lens, i.e. the first lens, second Lens, the third lens and the 4th lens.This four lens along optical axis from object side to image side sequential.

According to presently filed embodiment, the first lens can have negative power, and object side can be convex surface, and image side surface can For concave surface.First lens are arranged to be convex to the meniscus lens of object space, are conducive to ray-collecting as much as possible entering rear Optical system.- 3.0≤f1/f≤- 1.5 can be met between the focal length value f1 of first lens and the total focal length value f of optical lens, more Specifically, -2.56≤f1/f≤- 2.08 can be further met between f1 and f.

Second lens can have positive light coke, and object side and image side surface can be convex surface.Second lens of biconvex can be right The light that first lens are collected into is compressed, and makes light tendency smooth transition.The focal length value f2 and optics of second lens F2/f >=0.9 can be met between the total focal length value f of camera lens, more specifically, can further meet between f2 and f 1.00≤f2/f≤ 1.15。

The third lens can have negative power.In some embodiments, the image side surface of the third lens can be concave surface, object side Face can be convex surface.In other embodiments, the image side surface of the third lens can be concave surface, and object side can be concave surface.Third is saturating Mirror can be used for divergent rays, and light is made to can smoothly enter into rear optical system.The bent moon for being arranged to be convex to object side for the third lens is saturating Mirror or biconcave lens can favorably increase chief ray angle CRA.

4th lens can have positive light coke, and object side can be convex surface, and image side surface can be concave surface.4th lens can be used for Assemble light.4th lens are arranged to concave surface to be conducive to increase chief ray angle CRA towards the meniscus lens of image side；Meanwhile this The arrangement of sample also helps the bore for reducing the 4th lens.In the exemplary embodiment, the curvature of the image side surface of the 4th lens R4i/f >=1.3 can be met between radius R4i and the total focal length value f of optical lens, more specifically, further may be used between R4i and f Meet 1.58≤R4i/f≤5.77.By the rational design of the image side surface curvature to the 4th lens, be conducive to increase chief ray Angle CRA.

Optionally, the third lens can be combined into balsaming lens with the 4th lens glue.The use of balsaming lens is conducive to correct The overall structure of aberration, compact optical.

According to presently filed embodiment, optical lens, which may also include, to be for example arranged between the second lens and the third lens Diaphragm.Aperture arrangement between the second lens and the third lens, can for example collected into the light before and after diaphragm, before reducing diaphragm Lens group bore afterwards increases chief ray angle CRA.

In the exemplary embodiment, distance T on the object side to the axis of diaphragm of the first lens_BeforeWith diaphragm to optical lens Imaging surface axis on distance T_AfterwardsBetween can meet T_Before/T_Afterwards>=1.5, more specifically, T_BeforeAnd T_AfterwardsBetween can further meet 1.89 ≤T_Before/T_Afterwards≤1.90.With T_BeforeThe rear end size of the increase of ratio after/T, camera lens reduces, and is conducive to the chief ray for increasing camera lens Angle CRA.

In the application, also at least one of the second lens or the 4th lens can be arranged as non-spherical lens, with into one Step promotes the image quality of camera lens.The characteristics of non-spherical lens is: curvature is consecutive variations from lens centre to periphery.With from Lens centre has the spherical lens of constant curvature different to periphery, and non-spherical lens has more preferably radius of curvature characteristic, has Improve the advantages of distorting aberration and improving astigmatic image error.After non-spherical lens, can eliminate as much as possible imaging when The aberration occurred is waited, so as to improve image quality.

In the exemplary embodiment, the spacing distance T12 and optical lens of the first lens and the second lens on optical axis Total focal length value f between can meet T12/f >=1.5, more specifically, can further meet between T12 and f 1.86≤T12/f≤ 2.44.When diaphragm is set between the second lens and the third lens, by increasing the first lens and the second lens on optical axis Spacing distance T12 may make on the first lens object side to the axis of diaphragm in distance and diaphragm to the axis of imaging surface between distance Ratio increase, diaphragm is mobile to the direction close to imaging surface, to achieve the purpose that reduce camera lens rear end bore.

In the exemplary embodiment, optical lens has maximum field of view angle FOV, and the 4th thoroughly corresponding to maximum field of view angle It can meet between image height h and maximum field of view angle FOV corresponding to the maximum clear aperture D4i of mirror image side, maximum field of view angle D4i/h/FOV≤0.01, more specifically, can further meet 0.0085≤D4i/h/FOV≤0.0096 between D4i, h and FOV. When conditional D4i/h/FOV meets D4i/h/FOV≤0.01, camera lens can be embodied with lesser rear end bore.

Multi-disc eyeglass, such as described above four can be used according to the camera lens of the above embodiment of the application.Pass through Reasonable eyeglass arrangement, focal power distribution, airspace distribution, and the 4th lens are arranged as bent moon of the concave surface towards image side Lens can increase chief ray angle CRA in the case where guaranteeing camera lens big imaging size and high pixel；Meanwhile aforesaid way configures Camera lens can also realize rear end size reduce effect, camera lens is matched with chip, and can preferably be adapted to Such as the installation of on-vehicle lens is limited and is required.

However, it will be understood by those of skill in the art that without departing from this application claims technical solution the case where Under, the lens numbers for constituting camera lens can be changed, to obtain each result and advantage described in this specification.Although for example, It is described by taking four lens as an example in embodiment, but the optical lens is not limited to include four lens.If desired, The optical lens may also include the lens of other quantity.

The specific embodiment for being applicable to the optical lens of above embodiment is further described with reference to the accompanying drawings.

Embodiment 1

Referring to Fig. 1 description according to the optical lens of the embodiment of the present application 1.Fig. 1 is shown according to the embodiment of the present application 1 Optical lens structural schematic diagram.

As shown in Figure 1, optical lens includes from object side to four lens L1-L4 at image side sequential along optical axis. First lens L1 is the meniscus lens with negative power, and object side S1 is convex surface, and image side surface S2 is concave surface；Second lens L2 For the biconvex lens with positive light coke, object side S3 is convex surface, and image side surface S4 is convex surface；The third lens L3 is with negative light The meniscus lens of focal power, object side S6 are convex surface, and image side surface S7 is concave surface；And the 4th lens L4 be with positive light coke Meniscus lens, object side S7 are convex surface, and image side surface S8 is concave surface.Wherein, the third lens L3 and the 4th lens L4 gluing composition Balsaming lens.Optionally, optical lens may also include the colour filter L5 with object side S9 and image side surface S10.Optionally, optics Camera lens may also include the protection glass L5 with object side S9 and image side surface S10.Light from object sequentially passes through each surface S1 To S10 and it is ultimately imaged on imaging surface S11.

In the optical lens of the present embodiment, also it can be provided with diaphragm STO between the second lens L2 and the third lens L3, To improve the image quality of optical lens.

Table 1 shows radius of curvature R, thickness T, refractive index Nd and the Abbe of each lens of the optical lens of embodiment 1 Number Vd.

Face number	Radius of curvature R (mm)	Thickness T (mm)	Refractive index Nd	Abbe number Vd
					S1	21.9216	1.0000	1.52	64.21
S2	2.9275	5.9538
					S3	3.6183	4.0138	1.62	63.41
S4	-9.8106	0.0000
					STO	Infinity	0.1000
S6	5.2306	0.5500	1.92	20.88
					S7	2.9542	3.0000	1.62	63.41
S8	5.0500	1.0000
					S9	Infinity	0.7000	1.52	64.21
S10	Infinity	0.4162
					S11	Infinity

Table 1

It can be obtained according to the data in table 1, distance T on the object side to the axis of diaphragm STO of the first lens L1_BeforeWith diaphragm STO Distance T on to the axis of imaging surface S11_AfterwardsMeet T_Before/T_Afterwards=1.90.

The present embodiment uses four lens as an example, passing through the focal length and face type of each lens of reasonable distribution, is protecting In the case where demonstrate,proving camera lens big imaging size and high pixel, increase the incidence angle of electronics photosensitive element on chief ray incident imaging surface； Meanwhile reducing the rear end size of camera lens, in favor of the matching of camera lens and chip.In embodiment 1, the second lens L2 is aspherical Lens, face type Z are limited by following formula:

Wherein, Z be it is aspherical along optical axis direction when being highly the position of h, away from aspheric vertex of surface apart from rise；C is Aspherical paraxial curvature, c=1/R (that is, inverse that paraxial curvature c is upper 1 mean curvature radius R of table)；K is the constant of the cone；A, B, C, D, E are high-order coefficient.The following table 2 shows the circular cone that can be used for each aspherical lens surface S3 and S4 in embodiment 1 Constant k and high-order coefficient A, B, C, D and E.

Face number

k

A

B

C

D

E

S3

0.1213

-7.2237E-05

-4.7353E-04

1.4290E-04

-1.9938E-05

1.1187E-06

S4

17.9223

2.7830E-02

-4.3746E-02

5.2936E-02

-3.0322E-02

6.7156E-03

Table 2

It has been given in Table 3 the focal length value f1 of the first lens L1 of optical lens in embodiment 1, the focal length of the second lens L2 Value f2, the total focal length value f of optical lens, the maximum field of view angle FOV of optical lens, the 4th lens L4 corresponding to maximum field of view angle Image height h corresponding to the maximum clear aperture D4i of image side surface S8 and maximum field of view angle.

Parameter	f1(mm)	f2(mm)	f(mm)	FOV(°)	D4i(mm)	h(mm)
							Numerical value	-6.63	4.81	3.19	73	2.97	4.24

Table 3

In embodiment 1, the total focal length value f of the radius of curvature R 4i of the image side surface of the 4th lens L4 and optical lens meets R4i/f=1.58；The total focal length value f of the spacing distance T12 and optical lens of first lens L1 and the second lens L2 on optical axis Meet T12/f=1.86；The focal length value f2 of second lens L2 and the total focal length value f of optical lens meet f2/f=1.51；First The focal length value f1 of lens L1 and the total focal length value f of optical lens meet f1/f=-2.08；The maximum field of view angle FOV of optical lens =73 °；Corresponding to the maximum clear aperture D4i of 4th lens L4 image side surface S8, maximum field of view angle corresponding to maximum field of view angle Image height h and maximum field of view angle FOV meet D4i/h/FOV=0.0096.

Embodiment 2

The optical lens according to the embodiment of the present application 2 is described referring to Fig. 2.Fig. 2 shows implemented according to the application The structural schematic diagram of the optical lens of example 2.

As shown in Fig. 2, optical lens includes from object side to four lens L1-L4 at image side sequential along optical axis. First lens L1 is the meniscus lens with negative power, and object side S1 is convex surface, and image side surface S2 is concave surface；Second lens L2 For the biconvex lens with positive light coke, object side S3 is convex surface, and image side surface S4 is convex surface；The third lens L3 is with negative light The biconcave lens of focal power, object side S6 are concave surface, and image side surface S7 is concave surface；And the 4th lens L4 be with positive light coke Meniscus lens, object side S8 are convex surface, and image side surface S9 is concave surface.Optionally, optical lens may also include with object side S10 With the colour filter L5 of image side surface S11.Optionally, optical lens may also include the protection glass with object side S10 and image side surface S11 Glass L5.Light from object sequentially passes through each surface S1 to S11 and is ultimately imaged on imaging surface S12.

Table 4 shows radius of curvature R, thickness T, refractive index Nd and the Abbe of each lens of the optical lens of embodiment 2 Number Vd.Table 5 shows the constant of the cone k and high-order coefficient that can be used for each aspherical lens surface S8 and S9 in embodiment 2 A, B, C, D and E.The focal length value f1 of the first lens L1 of optical lens in embodiment 2, the coke of the second lens L2 are given in table 6 Away from the 4th lens corresponding to value f2, the total focal length value f of optical lens, the maximum field of view angle FOV of optical lens, maximum field of view angle Image height h corresponding to the maximum clear aperture D4i of L4 image side surface S9 and maximum field of view angle.Wherein, each aspherical face type can be by The formula (1) provided in above-described embodiment 1 limits.

Table 4

Face number

k

A

B

C

D

E

S8

-1.9000

-5.6659E-04

-1.4477E-03

-1.3711E-03

2.6902E-04

-2.3599E-04

S9

33.9630

1.2993E-02

-3.1812E-03

2.5322E-05

1.8578E-04

-1.9325E-04

Table 5

Parameter	f1(mm)	f2(mm)	f(mm)	FOV(°)	D4i(mm)	h(mm)
							Numerical value	-8.67	3.38	3.39	72.9	2.82	4.55

Table 6

In example 2, distance T on the object side of the first lens L1 to the axis of diaphragm STO_BeforeWith diaphragm STO to imaging surface Distance T on the axis of S11_AfterwardsMeet T_Before/T_Afterwards=1.89；The radius of curvature R 4i of the image side surface of 4th lens L4 and optical lens it is total Focal length value f meets R4i/f=5.77；Spacing distance T12 and optical lens of the first lens L1 and the second lens L2 on optical axis Total focal length value f meet T12/f=2.44；The focal length value f2 of second lens L2 and the total focal length value f of optical lens meet f2/f =1.00；The focal length value f1 of first lens L1 and the total focal length value f of optical lens meet f1/f=-2.56；Optical lens is most Big FOV=72.9 ° of field angle；The maximum clear aperture D4i of 4th lens L4 image side surface S9, maximum corresponding to maximum field of view angle Image height h corresponding to field angle and maximum field of view angle FOV meet D4i/h/FOV=0.0085.

To sum up, embodiment 1 and embodiment 2 meet relationship shown in following table 7 respectively.

Conditional embodiment	1	2
			R4i/f	1.58	5.77
T_Before/T_Afterwards	1.90	1.89
			T12/f	1.86	2.44
f2/f	1.51	1.00
			f1/f	-2.08	-2.56
D4i/h/FOV	0.0096	0.0085

Table 7

Above description is only the preferred embodiment of the application and the explanation to institute's application technology principle.Those skilled in the art Member is it should be appreciated that invention scope involved in the application, however it is not limited to technology made of the specific combination of above-mentioned technical characteristic Scheme, while should also cover in the case where not departing from the inventive concept, it is carried out by above-mentioned technical characteristic or its equivalent feature Any combination and the other technical solutions formed.Such as features described above has similar function with (but being not limited to) disclosed herein Can technical characteristic replaced mutually and the technical solution that forms.

Claims

It by object side to image side sequentially include: the first lens, the second lens, the third lens and along optical axis 1. optical lens Four lens,

It is characterized in that,

First lens have negative power, and object side is convex surface, and image side surface is concave surface；

Second lens have positive light coke, and object side and image side surface are convex surface；

The third lens have negative power；And

4th lens have positive light coke, and object side is convex surface, and image side surface is concave surface.
2. optical lens according to claim 1, which is characterized in that the object side of the third lens is convex surface, image side Face is concave surface.
3. optical lens according to claim 1, which is characterized in that the object side of the third lens and image side surface are Concave surface.
4. optical lens according to claim 1, which is characterized in that the third lens and the 4th lens gluing unit At balsaming lens.
5. optical lens according to claim 1, which is characterized in that in second lens and the 4th lens at least Having a piece of lens is non-spherical lens.
6. optical lens according to claim 1, which is characterized in that between second lens and the third lens It is provided with diaphragm.
7. optical lens according to claim 6, which is characterized in that the object side of first lens to the diaphragm Distance T on axis_BeforeWith distance T on the axis of the imaging surface of the diaphragm to the optical lens_AfterwardsMeet T_Before/T_Afterwards≥1.5。
8. optical lens according to any one of claim 1 to 7, which is characterized in that the image side surface of the 4th lens Radius of curvature R 4i and the total focal length value f of the optical lens meet R4i/f >=1.3.
9. optical lens according to any one of claim 1 to 7, which is characterized in that first lens and described The total focal length value f of spacing distance T12 of two lens on the optical axis and the optical lens meets T12/f >=1.5.
10. optical lens according to any one of claim 1 to 7, which is characterized in that the focal length value of second lens The total focal length value f of f2 and the optical lens meets f2/f >=0.9.
11. optical lens according to any one of claim 1 to 7, which is characterized in that the focal length value of first lens The total focal length value f of f1 and the optical lens meets -3.0≤f1/f≤- 1.5.
12. optical lens according to any one of claim 1 to 7, which is characterized in that D4i/h/FOV≤0.01,

Wherein, D4i is the maximum clear aperture of the 4th lens image side surface corresponding to the maximum field of view angle of optical lens；

H is image height corresponding to the maximum field of view angle of optical lens；And

FOV is the maximum field of view angle of optical lens.
It by object side to image side sequentially include: the first lens, the second lens, diaphragm and at least one along optical axis 13. optical lens A subsequent lens,

It is characterized in that,

First lens have negative power, and object side is convex surface, and image side surface is concave surface；

Second lens have positive light coke, and object side and image side surface are convex surface；And

Distance T on the object side of first lens to the axis of the diaphragm_BeforeWith the diaphragm to the imaging of the optical lens Distance T on the axis in face_AfterwardsMeet T_Before/T_Afterwards≥1.5。