CN111090168A

CN111090168A - Optical lens

Info

Publication number: CN111090168A
Application number: CN201811241820.4A
Authority: CN
Inventors: 张野; 王东方; 姚波
Original assignee: Ningbo Sunny Automotive Optech Co Ltd
Current assignee: Ningbo Sunny Automotive Optech Co Ltd
Priority date: 2018-10-24
Filing date: 2018-10-24
Publication date: 2020-05-01
Anticipated expiration: 2038-10-24
Also published as: CN111090168B

Abstract

The present application discloses an optical lens, which sequentially comprises, from an object side to an image side along an optical axis: the lens includes a first lens, a second lens, a third lens, a fourth lens and a fifth lens. The first lens can have negative focal power, and the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a concave surface; the second lens can have negative focal power, and the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; the third lens can have positive focal power, and both the object side surface and the image side surface of the third lens are convex surfaces; the fourth lens can have positive focal power, and both the object side surface and the image side surface of the fourth lens are convex surfaces; and the fifth lens may have a negative optical power. According to the optical lens, at least one of the advantages of high resolution, miniaturization, small aberration, small chromatic aberration, small aperture at the front end, low cost, long back focal length and the like can be achieved.

Description

Optical lens

Technical Field

The present application relates to an optical lens, and more particularly, to an optical lens including five lenses.

Background

With the development of scientific technology and the popularization of new technologies such as unmanned driving, the requirements of the vehicle-mounted lens on high definition of images, image comfort and the like are more and more strict as important parts in an automobile auxiliary driving system, such as chromatic aberration, definition and the like.

Due to the fact that the lens needs to be installed on an automobile, the oversized lens can not only cause interference to driving, but also seriously affect the aesthetic degree of the appearance of the automobile.

The vehicle-mounted lens has extremely high pixel requirement, and on the basis of the original lens, the resolution can be improved by increasing the number of the lenses generally, so that the high pixel requirement is met. In the conventional art, high resolution can be obtained by increasing the number of lenses to 6, 7 or more, but this seriously affects the miniaturization and low cost of the lens.

Therefore, an optical lens with high resolution and small aberration, miniaturization, low cost, etc. is needed to meet the application requirements in the market.

Disclosure of Invention

The present application provides an optical lens that is adaptable for on-board installation and that overcomes, at least in part, at least one of the above-identified deficiencies in the prior art.

An aspect of the present application provides an optical lens that may include, in order from an object side to an image side along an optical axis: the lens includes a first lens, a second lens, a third lens, a fourth lens and a fifth lens. The first lens can have negative focal power, and the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a concave surface; the second lens can have negative focal power, and the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; the third lens can have positive focal power, and both the object side surface and the image side surface of the third lens are convex surfaces; the fourth lens can have positive focal power, and both the object side surface and the image side surface of the fourth lens are convex surfaces; and the fifth lens may have a negative optical power.

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

In one embodiment, both the object-side surface and the image-side surface of the fifth lens may be concave.

In one embodiment, the second lens and the third lens may be cemented to each other to form a first cemented lens.

In one embodiment, the fourth lens and the fifth lens may be cemented with each other to form a second cemented lens.

In one embodiment, the total optical length TTL of the optical lens and the entire focal length F of the optical lens may satisfy: TTL/F is less than or equal to 3.8.

In one embodiment, the optical back focus BFL of the optical lens and the lens length TL of the optical lens may satisfy: BFL/TL is more than or equal to 0.25.

In one embodiment, the maximum field angle FOV of the optical lens, the maximum clear aperture D of the object-side surface of the first lens corresponding to the maximum field angle of the optical lens, and the image height H corresponding to the maximum field angle of the optical lens may satisfy: D/H/FOV is less than or equal to 0.035.

In one embodiment, the air space d5 between the third lens and the fourth lens and the total optical length TTL of the optical lens may satisfy: d5/TTL is more than or equal to 0.04.

In one embodiment, the combined focal length value F23 of the second lens and the third lens and the entire set of focal length values F of the optical lens may satisfy: F23/F is more than or equal to 0.7 and less than or equal to 1.4.

In one embodiment, the focal length value F4 of the fourth lens and the focal length value F5 of the fifth lens satisfy: the volume of the liquid F4/F5 is more than or equal to 0.6 and less than or equal to 1.4.

Another aspect of the present application provides an optical lens that may include, in order from an object side to an image side along an optical axis: the lens includes a first lens, a second lens, a third lens, a fourth lens and a fifth lens. The first lens, the second lens and the fifth lens can all have negative focal power; the third lens and the fourth lens can both have positive focal power; the second lens and the third lens may be cemented with each other to form a first cemented lens; the fourth lens and the fifth lens can be mutually glued to form a second glued lens; and the optical back focus BFL of the optical lens and the lens length TL of the optical lens can meet the following requirements: BFL/TL is more than or equal to 0.25.

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

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

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

In one embodiment, both the object-side surface and the image-side surface of the fourth lens can be convex.

The optical lens adopts five lenses, for example, the focal power of each lens is reasonably distributed and the cemented lens is formed by optimally setting the shape of the lens, so that at least one of the beneficial effects of high resolution, miniaturization, small aberration, small chromatic aberration, small aperture at the front end, low cost, long back focal length and the like of the optical lens is realized.

Drawings

Other features, objects, and advantages of the present application will become more apparent from the following detailed description of non-limiting embodiments when taken in conjunction with the accompanying drawings. In the drawings:

fig. 1 is a schematic view showing a structure of an optical lens according to embodiment 1 of the present application;

fig. 2 is a schematic structural view showing an optical lens according to embodiment 2 of the present application;

fig. 3 is a schematic structural view showing an optical lens according to embodiment 3 of the present application; and

fig. 4 is a schematic view showing a structure of an optical lens according to embodiment 4 of the present application.

Detailed Description

For a better understanding of the present application, various aspects of the present application will be described in more detail with reference to the accompanying drawings. It should be understood that the detailed description is merely illustrative of exemplary embodiments of the present application and does not limit the scope of the present application in any way. Like reference numerals refer to like elements throughout the specification. The expression "and/or" includes any and all combinations of one or more of the associated listed items.

It should be noted that in this specification, the expressions first, second, third, etc. are used only to distinguish one feature from another, and do not represent any limitation on the features. Thus, the first lens discussed below may also be referred to as the second lens or the third lens, and the first cemented lens may also be referred to as the second cemented lens, without departing from the teachings of the present application.

In the drawings, the thickness, size, and shape of the lens have been slightly exaggerated for convenience of explanation. In particular, the shapes of the spherical or aspherical surfaces shown in the drawings are shown by way of example. That is, the shape of the spherical surface or the aspherical surface is not limited to the shape of the spherical surface or the aspherical surface shown in the drawings. The figures are purely diagrammatic and not drawn to scale.

Herein, the paraxial region refers to a region near the optical axis. If the lens surface is convex and the convex position is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the concave position is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the object is called the object side surface, and the surface of each lens closest to the image plane is called the image side surface.

It will be further understood that the terms "comprises," "comprising," "has," "having," "includes" and/or "including," when used in this specification, specify the presence of stated features, elements, and/or components, but do not preclude the presence or addition of one or more other features, elements, components, and/or groups thereof. Moreover, when a statement such as "at least one of" appears after a list of listed features, the entirety of the listed features is modified rather than modifying individual elements in the list. Furthermore, when describing embodiments of the present application, the use of "may" mean "one or more embodiments of the present application. Also, the term "exemplary" is intended to refer to an example or illustration.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present application will be described in detail below with reference to the embodiments with reference to the attached drawings.

The features, principles, and other aspects of the present application are described in detail below.

An optical lens according to an exemplary embodiment of the present application includes, for example, five lenses having optical power, i.e., a first lens, a second lens, a third lens, a fourth lens, and a fifth lens. The five lenses are arranged in order from the object side to the image side along the optical axis.

The optical lens according to the exemplary embodiment of the present application may further include a photosensitive element disposed on the image plane. Alternatively, the photosensitive element provided to the imaging surface may be a photosensitive coupling element (CCD) or a complementary metal oxide semiconductor element (CMOS).

The first lens element can have a negative power, and can have a convex object-side surface and a concave image-side surface. The first lens is in a meniscus shape with the convex surface facing the object side, so that light with a large view field can be collected as far as possible, the light enters the rear optical system, the front end caliber is reduced, and the light flux is increased. In practical application, the vehicle-mounted lens is installed outdoors in a use environment and can be in severe weather such as rain, snow and the like, and the design of the meniscus shape protruding towards the object side is beneficial to the sliding of water drops and reduces the influence on imaging.

The second lens element can have a negative power, and can have a convex object-side surface and a concave image-side surface.

The third lens element can have a positive optical power, and both the object-side surface and the image-side surface can be convex.

The fourth lens element can have a positive optical power, and can have a convex object-side surface and a convex image-side surface.

The fifth lens element can have a negative power and can have a concave object-side surface and optionally a convex or concave image-side surface.

In an exemplary embodiment, a diaphragm for limiting the light beam may be disposed between, for example, the third lens and the fourth lens to further improve the imaging quality of the lens. When the diaphragm is arranged between the third lens and the fourth lens, light rays entering the optical system can be effectively converged, and the aperture of the lens of the optical system is reduced. Alternatively, in another exemplary embodiment, a diaphragm for limiting the light beam may be provided between, for example, the first lens and the second lens to further improve the imaging quality of the lens. It should be noted, however, that the above-described diaphragm positions are merely examples and are not limiting; in alternative embodiments, the diaphragm may be disposed at other positions according to actual needs.

In an exemplary embodiment, the optical lens according to the present application may further include a filter disposed between the fifth lens and the image plane to filter light rays having different wavelengths, as needed; and may further include a protective glass disposed between the optical filter and the imaging surface to prevent internal elements (e.g., chips) of the optical lens from being damaged.

As known to those skilled in the art, cemented lenses may be used to minimize or eliminate chromatic aberration. The use of the cemented lens in the optical lens can improve the image quality and reduce the reflection loss of light energy, thereby improving the imaging definition of the lens. In addition, the use of the cemented lens can also simplify the assembly process in the lens manufacturing process.

In an exemplary embodiment, the second lens and the third lens may be combined into the first cemented lens by cementing the image-side surface of the second lens with the object-side surface of the third lens. The first cemented lens effectively reduces the chromatic aberration of the system, makes the whole structure of the optical system compact, meets the miniaturization requirement, and simultaneously reduces the tolerance sensitivity problems of inclination/core deviation and the like generated in the assembling process of the lens unit. Since the discrete lens is easily sensitive to processing/assembling errors if the discrete lens is located at the turning point of the light, the use of the cemented lens effectively reduces the sensitivity.

In the first cemented lens, the second lens close to the object side has negative focal power, the third lens close to the image side has positive focal power, the negative film is arranged in front, and the positive film is arranged at the back, so that the front light can be dispersed, rapidly converged and then transited to the back, the optical path of the back light can be reduced, and the short TTL can be realized.

In an exemplary embodiment, the fourth lens and the fifth lens may be combined into a second cemented lens by cementing the image-side surface of the fourth lens with the object-side surface of the fifth lens. The second cemented lens can itself be achromatic, reducing tolerance sensitivity, and can also retain part of chromatic aberration to balance the chromatic aberration of the system.

In the second cemented lens, the fourth lens near the object side has positive power, and the fifth lens near the image side has negative power. The fourth lens with positive focal power is used behind the diaphragm, so that aberration generated by the front lens group can be further corrected, and meanwhile, light beams are converged again, so that the aperture of the lens can be enlarged, the total length of the lens can be shortened, the optical system is more compact, and the optical system has relatively short total length of the lens. The fifth lens is arranged to have a focal length close to that of the fourth lens to facilitate a smooth transition of light passing through the fourth lens to the imaging plane.

The use of the cemented lens shares the whole chromatic aberration correction of the system, can effectively correct the aberration, improves the resolving power, makes the optical system compact as a whole and meets the miniaturization requirement.

In an exemplary embodiment, an optical total length TTL of the optical lens and a whole set of focal length values F of the optical lens may satisfy: TTL/F is less than or equal to 3.8, and more ideally, TTL/F is less than or equal to 3.5. The condition formula TTL/F is less than or equal to 3.8, and the miniaturization characteristic of the system can be ensured.

In an exemplary embodiment, the optical back focus BFL of the optical lens and the lens length TL of the optical lens may satisfy: the BFL/TL ratio is more than or equal to 0.25, and more ideally, the BFL/TL ratio is more than or equal to 0.35. By satisfying the conditional expression BFL/TL is more than or equal to 0.25, the characteristic of the back focal length can be satisfied on the basis of realizing miniaturization, and the assembly of the optical lens is facilitated.

In an exemplary embodiment, the maximum field angle FOV of the optical lens, the maximum clear aperture D of the object-side surface of the first lens corresponding to the maximum field angle of the optical lens, and the image height H corresponding to the maximum field angle of the optical lens may satisfy: D/H/FOV is 0.035 or less, and preferably, D/H/FOV is 0.025 or less. The conditional expression D/H/FOV is less than or equal to 0.035, and the small-caliber characteristic of the front end of the lens can be realized.

In an exemplary embodiment, an air interval d5 between the third lens and the fourth lens and an optical total length TTL of the optical lens may satisfy: d5/TTL is not less than 0.04, more preferably d5/TTL is not less than 0.06. The central distance between the first cemented lens and the second cemented lens is larger through arrangement, so that smooth transition of light rays near the diaphragm is facilitated, and the improvement of image quality is facilitated.

In an exemplary embodiment, a combined focal length value F23 of the second lens and the third lens and a full set focal length value F of the optical lens may satisfy: F23/F is 0.7. ltoreq. F23/F.ltoreq.1.4, and more preferably, F23/F.ltoreq.1.2 is 0.9. ltoreq.F. By controlling the light trend between the first lens and the fourth lens, the aberration caused by large-angle light entering through the first lens can be reduced, and meanwhile, the structure of the lens is compact, so that the miniaturization characteristic is realized.

In an exemplary embodiment, a focal length value F4 of the fourth lens and a focal length value F5 of the fifth lens may satisfy: an agent F4/F5 is 0.6 ≦ 1.4, and more preferably, it further satisfies 0.8 ≦ F4/F5 | ≦ 1.2. The arrangement is such that the focal lengths of the adjacent fourth and fifth lenses are close to each other, which can help smooth transition of light.

In an exemplary embodiment, the first lens in the optical lens according to the present application may employ an aspherical mirror. The aspheric lens has the characteristics that: the curvature varies continuously from the center of the lens to the periphery. Unlike a spherical lens having a constant curvature from the center to the periphery of the lens, an aspherical lens has better curvature radius characteristics, and has the advantages of improving distortion aberration and improving astigmatic aberration. After the aspheric lens is adopted, the aberration generated in imaging can be eliminated as much as possible, so that the imaging quality of the lens is improved. For example, the first lens may be an aspheric lens to further improve the resolution quality. It is understood that the optical lens according to the present application may increase the number of aspherical lenses in order to improve the imaging quality.

In an exemplary embodiment, the lens used in the optical lens may be a plastic lens, or may be a glass lens. The lens made of plastic has a large thermal expansion coefficient, and when the ambient temperature change of the lens is large, the lens made of plastic causes a large amount of change of the optical back focus of the lens. The glass lens can reduce the influence of temperature on the optical back focus of the lens, but has higher cost.

According to the optical lens of the above embodiment of the present application, the high resolution requirement can be achieved only by using 5-piece structure by setting the reasonable lens shape and the reasonable focal power, and the optical lens can satisfy the low cost requirements of small aberration, low sensitivity and high production yield while satisfying the miniaturization. Therefore, the optical lens according to the above-mentioned embodiment of the present application can have at least one of the advantages of high resolution, miniaturization, small aberration, small chromatic aberration, small aperture at the front end, low cost, long back focal length, and the like, and can better meet the requirements of the on-vehicle lens.

It will be understood by those skilled in the art that the total optical length TTL of the optical lens used above refers to the on-axis distance from the center of the object-side surface of the first lens to the center of the imaging surface; the optical back focus BFL of the optical lens refers to the axial distance from the center of the image side surface of the fifth lens of the last lens to the center of the imaging surface; and the lens group length TL of the optical lens means an on-axis distance from the center of the object-side surface of the first lens to the center of the image-side surface of the last lens, i.e., the fifth lens.

It will be understood by those skilled in the art that the number of lenses making up the lens barrel may be varied to achieve the various results and advantages described in this specification without departing from the claimed subject matter. For example, although five lenses are exemplified in the embodiment, the optical lens is not limited to include five lenses. The optical lens may also include other numbers of lenses, if desired.

Specific examples of an optical lens applicable to the above-described embodiments are further described below with reference to the drawings.

Example 1

An optical lens according to embodiment 1 of the present application is described below with reference to fig. 1. Fig. 1 shows a schematic structural diagram of an optical lens according to embodiment 1 of the present application.

As shown in fig. 1, the optical lens includes, 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 first lens L1 is a meniscus lens with negative power, with the object side S1 being convex and the image side S2 being concave. The first lens element L1 is an aspherical lens, and both the object-side surface S1 and the image-side surface S2 are aspherical.

The second lens L2 is a meniscus lens with negative power, with the object side S3 being convex and the image side S4 being concave. The third lens L3 is a biconvex lens with positive optical power, and has both the object-side surface S4 and the image-side surface S5 being convex. Wherein the second lens L2 and the third lens L3 are cemented with each other to form a first cemented lens.

The fourth lens L4 is a biconvex lens with positive optical power, and has both the object-side surface S7 and the image-side surface S8 convex. The fifth lens L5 is a meniscus lens with negative power, with the object side S8 being concave and the image side S9 being convex. Wherein the fourth lens L4 and the fifth lens L5 are cemented with each other to form a second cemented lens.

Optionally, the optical lens may further include a filter L6 and/or a protective lens L6' having an object side S10 and an image side S11. Filter L6 can be used to correct for color deviations. The protective lens L6' may be used to protect the image sensing chip on the imaging plane IMA. Light from the object passes through each of the surfaces S1 to S11 in sequence and is finally imaged on the imaging plane IMA.

In the optical lens of the present embodiment, a stop STO may be provided between the third lens L3 and the fourth lens L4 (i.e., between the first cemented lens and the second cemented lens) to improve the imaging quality.

Table 1 shows a radius of curvature R, a thickness T, a refractive index Nd, and an abbe number Vd of each lens of the optical lens of example 1, where the radius of curvature R and the thickness T are both in units of millimeters (mm).

TABLE 1

Flour mark	Radius of curvature R	Thickness T	Refractive index Nd	Abbe number Vd
					1	4.8533	1.3000	1.52	64.21
2	2.0818	2.9000
					3	50.0000	1.0000	1.81	33.28
4	5.3000	3.0000	1.74	49.24
					5	-4.9000	1.0000
STO	All-round	0.5000
					7	0.5000	3.0000	1.59	61.25
8	-5.0000	1.0000	1.78	25.72
					9	-35.0000	0.1000
10	All-round	0.9500	1.52	64.21
					11	All-round	4.2500
IMA	All-round

The present embodiment adopts five lenses as an example, and by reasonably distributing the focal power and the surface type of each lens, the center thickness of each lens and the air space between each lens, the lens can have at least one of the advantages of high resolution, miniaturization, small aberration, small chromatic aberration, small aperture at the front end, low cost, long back focal length and the like. Each aspherical surface type Z is defined by the following formula:

wherein Z is the distance rise from the vertex of the aspheric surface 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 coefficient conc; A. b, C, D, E are all high order term coefficients. Table 2 below shows the conic coefficients k and the high-order term coefficients A, B, C, D and E that can be used for the aspherical lens surfaces S1-S2 in example 1.

TABLE 2

Flour mark

K

A

B

C

D

E

1

-0.6092

-5.4529E-03

-1.3583E-04

-1.1751E-05

-1.0934E-05

3.0000E-07

2

-0.3524

-1.1510E-02

-6.4987E-05

1.0403E-05

1.3146E-05

-6.5838E-06

Table 3 below shows the maximum clear aperture D of the object-side surface S1 of the first lens L1 corresponding to the maximum field angle of the optical lens in embodiment 1, the image height H corresponding to the maximum field angle of the optical lens, the maximum field angle FOV of the optical lens, the combined focal length value F23 of the second lens L2 and the third lens L3 (i.e., the focal length value of the first cemented lens), the focal length value F4 of the fourth lens L4, the focal length value F5 of the fifth lens L5, the entire group focal length value F of the optical lens, the optical total length TTL of the optical lens (i.e., the on-axis distance from the center of the object-side surface S1 of the first lens L1 to the center of the imaging surface IMA), the lens length TL (i.e., the on-axis distance from the center of the object-side surface S1 of the first lens L1 to the center of the image-side surface S9 of the fifth lens L5), the optical lens post-optical BFL (i.e., the optical lens BFL post-axis distance from the center of the image-side surface S9 of the fifth lens L5) of the optical lens in embodiment 1, And an air space d5 between the third lens L3 and the fourth lens L4.

TABLE 3

D(mm)	4.6468	F(mm)	5.5884
				H(mm)	4.8040	TTL(mm)	19.0000
FOV(°)	54	TL(mm)	13.7000
				F23(mm)	6.4900	BFL(mm)	5.3000
F4(mm)	6.6513	d5(mm)	1.5000
				F5(mm)	-7.2244

In the present embodiment, BFL/TL is 0.3869 between the optical back focus BFL of the optical lens and the lens length TL of the optical lens; the maximum field angle FOV of the optical lens, the maximum clear aperture D of the object-side surface S1 of the first lens L1 corresponding to the maximum field angle of the optical lens, and the image height H corresponding to the maximum field angle of the optical lens satisfy D/H/FOV of 0.0179; the total optical length TTL of the optical lens and the whole group focal length value F of the optical lens meet the condition that TTL/F is 3.3999; F23/F1.1613 is satisfied between the combined focal length value F23 of the second lens L2 and the third lens L3 and the entire group focal length value F of the optical lens; an | F4/F5 | 0.9207 is satisfied between the focal length value F4 of the fourth lens L4 and the focal length value F5 of the fifth lens L5; and d5/TTL 0.0789 is satisfied between the air interval d5 between the third lens L3 and the fourth lens L4 and the total optical length TTL of the optical lens.

Example 2

An optical lens according to embodiment 2 of the present application is described below with reference to fig. 2. In this embodiment and the following embodiments, descriptions of parts similar to those of embodiment 1 will be omitted for the sake of brevity. Fig. 2 shows a schematic structural diagram of an optical lens according to embodiment 2 of the present application.

As shown in fig. 2, the optical lens includes, in order from the object side to the image side along the optical axis, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, and a fifth lens L5.

The second lens L2 is a meniscus lens with negative power, with the object side S4 being convex and the image side S5 being concave. The third lens L3 is a biconvex lens with positive optical power, and has both the object-side surface S5 and the image-side surface S6 being convex. Wherein the second lens L2 and the third lens L3 are cemented with each other to form a first cemented lens.

In the optical lens of the present embodiment, a stop STO may be provided between the first lens L1 and the second lens L2 to improve the imaging quality.

Table 4 below shows a radius of curvature R, a thickness T, a refractive index Nd, and an abbe number Vd of each lens of the optical lens of example 2, where the radius of curvature R and the thickness T are both in units of millimeters (mm). The following table 5 shows the conic coefficients k and the high-order term coefficients A, B, C, D and E that can be used for the aspherical lens surfaces S1-S2 in example 2. Table 6 below gives the maximum clear aperture D of the object-side surface S1 of the first lens L1 corresponding to the maximum angle of view of the optical lens of example 2, the image height H corresponding to the maximum angle of view of the optical lens, the maximum angle of view FOV of the optical lens, the combined focal length value F23 (i.e., the focal length value of the first cemented lens) of the second lens L2 and the third lens L3, the focal length value F4 of the fourth lens L4, the focal length value F5 of the fifth lens L5, the entire group focal length value F of the optical lens, the optical total length TTL of the optical lens, the lens length TL of the optical lens, the optical back focus BFL of the optical lens, and the air interval D5 between the third lens L3 and the fourth lens L4.

TABLE 4

Flour mark	Radius of curvature R	Thickness T	Refractive index Nd	Abbe number Vd
					1	5.2326	1.3000	1.52	64.21
2	1.8232	2.5000
					STO	All-round	0.5000
4	23.0000	1.0000	1.81	33.28
					5	4.5230	3.0000	1.74	49.24
6	-4.6232	1.4000
					7	10.8219	3.0000	1.59	61.25
8	-3.6461	1.0000	1.78	25.72
					9	-50.0000	0.1000
10	All-round	0.9500	1.52	64.21
					11	All-round	4.2771
IMA	All-round

TABLE 5

Flour mark

K

A

B

C

D

E

1

-0.6092

-7.5578E-04

6.8384E-06

-9.7149E-07

-1.4333E-07

1.1299E-08

2

-0.3524

-2.8773E-03

-6.4987E-05

1.0087E-05

-2.3465E-07

-1.9588E-06

TABLE 6

D(mm)	5.4687	F(mm)	5.6166
				H(mm)	4.9100	TTL(mm)	19.0271
FOV(°)	53	TL(mm)	13.7000
				F23(mm)	5.7500	BFL(mm)	5.3271
F4(mm)	4.9963	d5(mm)	1.4000
				F5(mm)	-5.0142

In the present embodiment, BFL/TL is 0.3888 between the optical back focus BFL of the optical lens and the lens length TL of the optical lens; the maximum field angle FOV of the optical lens, the maximum light-passing aperture D of the object side surface S1 of the first lens L1 corresponding to the maximum field angle of the optical lens and the image height H corresponding to the maximum field angle of the optical lens satisfy that D/H/FOV is 0.0210; the total optical length TTL of the optical lens and the whole group focal length value F of the optical lens meet the condition that TTL/F is 3.3877; F23/F1.0238 is satisfied between the combined focal length value F23 of the second lens L2 and the third lens L3 and the entire group focal length value F of the optical lens; an | F4/F5 | 0.9964 is satisfied between the focal length value F4 of the fourth lens L4 and the focal length value F5 of the fifth lens L5; and d5/TTL of 0.0736 is satisfied between the air interval d5 between the third lens L3 and the fourth lens L4 and the total optical length TTL of the optical lens.

Example 3

An optical lens according to embodiment 3 of the present application is described below with reference to fig. 3. In this embodiment and the following embodiments, descriptions of parts similar to those of embodiment 1 will be omitted for the sake of brevity. Fig. 3 shows a schematic structural diagram of an optical lens according to embodiment 3 of the present application.

As shown in fig. 3, the optical lens includes, in order from the object side to the image side along the optical axis, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, and a fifth lens L5.

The fourth lens L4 is a biconvex lens with positive optical power, and has both the object-side surface S7 and the image-side surface S8 convex. The fifth lens L5 is a biconcave lens with negative optical power, and both the object-side surface S8 and the image-side surface S9 are concave. Wherein the fourth lens L4 and the fifth lens L5 are cemented with each other to form a second cemented lens.

Table 7 below shows a radius of curvature R, a thickness T, a refractive index Nd, and an abbe number Vd of each lens of the optical lens of example 3, where the radius of curvature R and the thickness T are both in units of millimeters (mm). Table 8 below shows the conic coefficients k and the high-order term coefficients A, B, C, D and E that can be used for the aspherical lens surfaces S1-S2 in example 3. Table 9 below gives the maximum clear aperture D of the object-side surface S1 of the first lens L1 corresponding to the maximum angle of view of the optical lens of example 3, the image height H corresponding to the maximum angle of view of the optical lens, the maximum angle of view FOV of the optical lens, the combined focal length value F23 (i.e., the focal length value of the first cemented lens) of the second lens L2 and the third lens L3, the focal length value F4 of the fourth lens L4, the focal length value F5 of the fifth lens L5, the entire group focal length value F of the optical lens, the optical total length TTL of the optical lens, the lens length TL of the optical lens, the optical back focus BFL of the optical lens, and the air interval D5 between the third lens L3 and the fourth lens L4.

TABLE 7

Flour mark	Radius of curvature R	Thickness T	Refractive index Nd	Abbe number Vd
					1	6.1616	1.3000	1.59	61.25
2	2.4000	3.0000
					3	30.5000	1.0000	1.81	33.28
4	4.5550	3.0000	1.74	49.24
					5	-5.1304	1.0000
STO	All-round	0.6000
					7	7.0000	3.0000	1.59	61.25
8	-7.5500	1.0000	1.78	25.72
					9	25.0000	0.1000
10	All-round	0.9500	1.52	64.21
					11	All-round	4.0959
IMA	All-round

TABLE 8

Flour mark

K

A

B

C

D

E

1

-5.6223

-5.9323E-03

-1.0953E-05

7.6991E-05

-1.0953E-05

4.6302E-07

2

-0.5000

-1.1334E-02

-1.1751E-05

4.7958E-05

1.3162E-05

-3.2237E-06

TABLE 9

In the present embodiment, BFL/TL is 0.3702 between the optical back focus BFL of the optical lens and the lens length TL of the optical lens; the maximum field angle FOV of the optical lens, the maximum clear aperture D of the object-side surface S1 of the first lens L1 corresponding to the maximum field angle of the optical lens, and the image height H corresponding to the maximum field angle of the optical lens satisfy D/H/FOV of 0.0203; the total optical length TTL of the optical lens and the whole group focal length value F of the optical lens meet the condition that TTL/F is 3.3839; F23/F1.1620 is satisfied between the combined focal length value F23 of the second lens L2 and the third lens L3 and the entire group focal length value F of the optical lens; an | F4/F5 | 0.9207 is satisfied between the focal length value F4 of the fourth lens L4 and the focal length value F5 of the fifth lens L5; and d5/TTL 0.0840 is satisfied between the air interval d5 between the third lens L3 and the fourth lens L4 and the total optical length TTL of the optical lens.

Example 4

An optical lens according to embodiment 4 of the present application is described below with reference to fig. 4. In this embodiment and the following embodiments, descriptions of parts similar to those of embodiment 1 will be omitted for the sake of brevity. Fig. 4 shows a schematic structural diagram of an optical lens according to embodiment 4 of the present application.

As shown in fig. 4, the optical lens includes, in order from the object side to the image side along the optical axis, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, and a fifth lens L5.

Table 10 below shows a radius of curvature R, a thickness T, a refractive index Nd, and an abbe number Vd of each lens of the optical lens of example 4, where the radius of curvature R and the thickness T are both in units of millimeters (mm). The following table 11 shows the conic coefficients k and the high-order term coefficients A, B, C, D and E that can be used for the aspherical lens surfaces S1-S2 in example 4. Table 12 below gives the maximum clear aperture D of the object-side surface S1 of the first lens L1 corresponding to the maximum angle of view of the optical lens of example 4, the image height H corresponding to the maximum angle of view of the optical lens, the maximum angle of view FOV of the optical lens, the combined focal length value F23 (i.e., the focal length value of the first cemented lens) of the second lens L2 and the third lens L3, the focal length value F4 of the fourth lens L4, the focal length value F5 of the fifth lens L5, the entire group focal length value F of the optical lens, the optical total length TTL of the optical lens, the lens length TL of the optical lens, the optical back focus BFL of the optical lens, and the air interval D5 between the third lens L3 and the fourth lens L4.

Watch 10

Flour mark	Radius of curvature R	Thickness T	Refractive index Nd	Abbe number Vd
					1	6.2592	1.3000	1.59	61.25
2	2.3780	2.5000
					STO	All-round	0.5000
4	28.4226	1.0000	1.81	33.28
					5	4.5310	3.0000	1.74	49.24
6	-5.0839	1.4000
					7	6.6500	3.0000	1.59	61.25
8	-6.6500	1.0000	1.78	25.72
					9	20.0000	0.1000
10	All-round	0.9500	1.52	64.21
					11	All-round	4.1995
IMA	All-round

TABLE 11

Flour mark

K

A

B

C

D

E

1

-10.0000

-4.7717E-03

-3.2224E-04

9.1556E-05

-1.1731E-05

5.9509E-07

2

-0.2906

-9.5615E-03

-6.8002E-04

1.5788E-05

1.2390E-06

-3.8367E-06

TABLE 12

D(mm)	4.7463	F(mm)	5.5766
				H(mm)	4.6580	TTL(mm)	18.9495
FOV(°)	52	TL(mm)	13.7000
				F23(mm)	6.4300	BFL(mm)	5.2495
F4(mm)	6.1364	d5(mm)	1.4000
				F5(mm)	-6.1992

In the present embodiment, BFL/TL is 0.3832 between the optical back focus BFL of the optical lens and the lens length TL of the optical lens; the maximum field angle FOV of the optical lens, the maximum clear aperture D of the object-side surface S1 of the first lens L1 corresponding to the maximum field angle of the optical lens, and the image height H corresponding to the maximum field angle of the optical lens satisfy D/H/FOV of 0.0196; the total optical length TTL of the optical lens and the whole group focal length value F of the optical lens meet the condition that TTL/F is 3.3980; F23/F1.1530 is satisfied between the combined focal length value F23 of the second lens L2 and the third lens L3 and the entire group focal length value F of the optical lens; an | F4/F5 | 0.9899 is satisfied between the focal length value F4 of the fourth lens L4 and the focal length value F5 of the fifth lens L5; and d5/TTL of 0.0739 is satisfied between the air interval d5 between the third lens L3 and the fourth lens L4 and the total optical length TTL of the optical lens.

In summary, examples 1 to 4 each satisfy the relationship shown in table 13 below.

Watch 13

The above description is only a preferred embodiment of the application and is illustrative of the principles of the technology employed. It will be appreciated by a person skilled in the art that the scope of the invention as referred to in the present application is not limited to the embodiments with a specific combination of the above-mentioned features, but also covers other embodiments with any combination of the above-mentioned features or their equivalents without departing from the inventive concept. For example, the above features may be replaced with (but not limited to) features having similar functions disclosed in the present application.

Claims

1. The optical lens sequentially comprises from an object side to an image side along an optical axis: a first lens, a second lens, a third lens, a fourth lens, and a fifth lens,

it is characterized in that the preparation method is characterized in that,

the first lens has negative focal power, the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a concave surface;

the second lens has negative focal power, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface;

the third lens has positive focal power, and both the object side surface and the image side surface of the third lens are convex surfaces;

the fourth lens has positive focal power, and both the object side surface and the image side surface of the fourth lens are convex surfaces; and

the fifth lens has a negative power.

2. An optical lens barrel according to claim 1, wherein the fifth lens element has a concave object-side surface and a convex image-side surface.

3. An optical lens barrel according to claim 1, wherein the fifth lens element has both object and image side surfaces that are concave.

4. An optical lens according to claim 1, wherein the second lens and the third lens are cemented to each other to form a first cemented lens.

5. An optical lens according to claim 1, wherein the fourth lens and the fifth lens are cemented to each other to form a second cemented lens.

6. An optical lens according to any one of claims 1 to 5, wherein an overall optical length TTL of the optical lens and a total group focal length value F of the optical lens satisfy: TTL/F is less than or equal to 3.8.

7. An optical lens according to any of claims 1-5, characterized in that between the optical back focus BFL of the optical lens and the lens length TL of the optical lens satisfies: BFL/TL is more than or equal to 0.25.

8. An optical lens according to any one of claims 1 to 5, wherein the maximum field angle FOV of the optical lens, the maximum clear aperture D of the object-side surface of the first lens corresponding to the maximum field angle of the optical lens, and the image height H corresponding to the maximum field angle of the optical lens satisfy: D/H/FOV is less than or equal to 0.035.

9. An optical lens according to any one of claims 1 to 5, characterized in that an air interval d5 between the third lens and the fourth lens and an optical total length TTL of the optical lens satisfy: d5/TTL is more than or equal to 0.04.

10. An optical lens according to any one of claims 1 to 5, characterized in that a combined focal length value F23 of the second lens and the third lens and a full set of focal length values F of the optical lens satisfy: F23/F is more than or equal to 0.7 and less than or equal to 1.4.

11. An optical lens according to any one of claims 1 to 5, characterized in that a focal length value F4 of the fourth lens and a focal length value F5 of the fifth lens satisfy: the volume of the liquid F4/F5 is more than or equal to 0.6 and less than or equal to 1.4.

12. The optical lens sequentially comprises from an object side to an image side along an optical axis: a first lens, a second lens, a third lens, a fourth lens, and a fifth lens,

it is characterized in that the preparation method is characterized in that,

the first lens, the second lens and the fifth lens each have a negative optical power;

the third lens and the fourth lens each have positive optical power;

the second lens and the third lens are mutually glued to form a first glued lens;

the fourth lens and the fifth lens are mutually glued to form a second cemented lens; and

the optical back focus BFL of the optical lens and the lens length TL of the optical lens meet the following conditions: BFL/TL is more than or equal to 0.25.