CN112444938B

CN112444938B - Optical lens and electronic device

Info

Publication number: CN112444938B
Application number: CN201910803292.5A
Authority: CN
Inventors: 栾晓宇; 王东方
Original assignee: Ningbo Sunny Automotive Optech Co Ltd
Current assignee: Ningbo Sunny Automotive Optech Co Ltd
Priority date: 2019-08-28
Filing date: 2019-08-28
Publication date: 2023-03-21
Anticipated expiration: 2039-08-28
Also published as: CN112444938A

Abstract

The application discloses an optical lens and an electronic device including the same. The optical lens assembly sequentially comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens from an object side to an image side along an optical axis, wherein: 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 optical power; the third lens has positive optical power; the fourth lens has positive focal power, the object side surface of the fourth lens is a convex surface, and the image side surface of the fourth lens is a convex surface; the fifth lens has optical power; and the sixth lens has optical power. The optical lens can realize at least one of the advantages of high resolution, miniaturization, low cost, good temperature adaptability and the like.

Description

Optical lens and electronic device

Technical Field

The present disclosure relates to the field of optical elements, and more particularly, to an optical lens and an electronic device.

Background

With the rapid development of the driving assistance system of the automobile, the optical lens plays an increasingly important role therein. In particular, the vehicle-mounted side-view lens plays an important role in an automatic driving system. Due to the consideration of safety, the optical lens for vehicle-mounted application has more strict requirements on optical parameters in some aspects, and especially has higher and higher requirements on the resolving power performance of the optical lens. Meanwhile, the demand for miniaturization of the lens is increasing in the market. Therefore, there is a need for an optical lens that combines resolving power and miniaturization.

Disclosure of Invention

One aspect of the present application provides an optical lens, in order from an object side to an image side along an optical axis, comprising: the lens comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens, wherein 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 focal power; the third lens has positive focal power; the fourth lens has positive focal power, and the object side surface of the fourth lens is a convex surface, and the image side surface of the fourth lens is a convex surface; the fifth lens has focal power; and the sixth lens has optical power.

In one embodiment, the optical power of the second lens element is negative, and the object-side surface and the image-side surface of the second lens element are convex and concave.

In one embodiment, the optical power of the second lens is positive optical power, and the object-side surface and the image-side surface of the second lens are concave and convex.

In one embodiment, the third lens element has a convex object-side surface and a concave image-side surface.

In one embodiment, the object-side surface of the third lens element is convex and the image-side surface of the third lens element is convex.

In one embodiment, the third lens element has a concave object-side surface and a convex image-side surface.

In one embodiment, the optical power of the fifth lens is positive optical power, and the object-side surface and the image-side surface of the fifth lens are convex.

In one embodiment, the optical power of the fifth lens element is negative, and the object-side surface and the image-side surface of the fifth lens element are convex and concave.

In one embodiment, the power of the sixth lens element is positive power, and the object-side surface and the image-side surface of the sixth lens element are convex.

In one embodiment, the power of the sixth lens element is negative, and the object-side surface and the image-side surface of the sixth lens element are concave.

In one embodiment, the power of the sixth lens element is negative, and the object-side surface and the image-side surface of the sixth lens element are concave and convex.

In one embodiment, the fifth lens and the sixth lens are cemented to form a cemented lens.

In one embodiment, at least two lenses of the first lens to the sixth lens are aspherical lenses.

In one embodiment, the second lens, the third lens, and the fourth lens are all aspheric lenses.

In one embodiment, a distance TTL between an object side surface of the first lens element and an imaging surface of the optical lens on an optical axis and a total effective focal length F of the optical lens satisfy: TTL/F is less than or equal to 10.

In one embodiment, a distance BFL on the optical axis from the image-side surface of the sixth lens element to the image plane of the optical lens and a distance TL on the optical axis from the object-side surface of the first lens element to the image-side surface of the sixth lens element satisfy: BFL/TL is more than or equal to 0.1.

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 FOV, and the image height H corresponding to the maximum field angle FOV satisfy: D/H/FOV is less than or equal to 0.025.

In one embodiment, a distance d12 between the image side surface of the first lens and the object side surface of the second lens on the optical axis and a distance TTL between the object side surface of the first lens and the imaging surface of the optical lens on the optical axis satisfy: d12/TTL is less than or equal to 0.25.

In one embodiment, a distance d34 between the image side surface of the third lens and the object side surface of the fourth lens on the optical axis and the total effective focal length F of the optical lens satisfy: d34/F is less than or equal to 0.95.

In one embodiment, the effective focal length F5 of the fifth lens and the effective focal length F6 of the sixth lens satisfy: the absolute value of F5/F6 is more than or equal to 0.5 and less than or equal to 1.5.

In one embodiment, the maximum field angle FOV of the optical lens, the total effective focal length F of the optical lens, and the image height H corresponding to the maximum field angle FOV satisfy: (FOV F)/H.gtoreq.45.

In one embodiment, the effective focal length F4 of the fourth lens and the radius of curvature R41 of the object side surface of the fourth lens satisfy: the absolute value of F4/R41 is more than or equal to 0.1 and less than or equal to 1.2.

In one embodiment, the radius of curvature R11 of the object-side surface of the first lens and the radius of curvature R21 of the object-side surface of the second lens satisfy: the | R11/R21| is more than or equal to 0.15.

In one embodiment, the effective focal length F2 of the second lens and the total effective focal length F of the optical lens satisfy: F2/F is more than or equal to-5 and less than or equal to-1.5.

Another aspect of the present disclosure provides an optical lens, in order from an object side to an image side along an optical axis, comprising: the lens comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens, wherein the first lens has negative focal power; the second lens has focal power; the third lens has positive focal power; the fourth lens has positive focal power; the fifth lens has focal power; and the sixth lens has optical power, wherein: the distance d34 between the image side surface of the third lens and the object side surface of the fourth lens on the optical axis and the total effective focal length F of the optical lens satisfy that: d34/F is less than or equal to 0.95.

In one embodiment, the first lens element has a convex object-side surface and a concave image-side surface.

In one embodiment, the fourth lens element has a convex object-side surface and a convex image-side surface.

In one embodiment, the optical power of the sixth lens element is negative, and the object-side surface and the image-side surface of the sixth lens element are concave.

In one embodiment, the effective focal length F1 of the first lens and the total effective focal length F of the optical lens satisfy: F1/F is more than or equal to-3 and less than or equal to-2.

In one embodiment, the effective focal length F3 of the third lens and the total effective focal length F of the optical lens satisfy: F3/F is more than or equal to 2.5 and less than or equal to 28.

Still another aspect of the present application provides an electronic apparatus that may include the optical lens according to the above-described embodiment and an imaging element for converting an optical image formed by the optical lens into an electrical signal.

The six lenses are adopted, and the shape, focal power and the like of each lens are optimally set, so that the optical lens has at least one beneficial effect of high resolution, miniaturization, small distortion, low cost, good temperature adaptability and the like.

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;

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

fig. 5 is a schematic structural view showing an optical lens according to embodiment 5 of the present application;

fig. 6 is a schematic view showing a structure of an optical lens according to embodiment 6 of the present application;

fig. 7 is a schematic structural view showing an optical lens according to embodiment 7 of the present application; and

fig. 8 is a schematic view showing a structure of an optical lens according to embodiment 8 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 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 of the lens, and the surface of each lens closest to the image side is called the image side surface of the lens.

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, in the present application, the embodiments and features of the embodiments 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.

In an exemplary embodiment, the optical lens includes, for example, six lenses having optical powers, i.e., a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens. The six lenses are arranged along the optical axis in sequence from the object side to the image side.

In an exemplary embodiment, the optical lens 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 may have a negative power and have a meniscus shape, its object side may be convex, and its image side may be concave. The optical power and the surface type configuration of the first lens are beneficial to collecting incident rays with a large field angle, and ensure that as much rays as possible enter the optical system, so that the luminous flux is increased, and the illumination is improved. In practical application, the vehicle-mounted lens is generally exposed to the external environment, and the meniscus lens protruding towards the object side is beneficial to rain and snow to slide along the lens, so that the service life of the lens is prolonged.

The second lens element can have a negative power, and can have a convex object-side surface and a concave image-side surface. In addition, the second lens element can have a positive optical power, and can have a concave object-side surface and a convex image-side surface. The second lens according to the embodiment of the present application can compress the light collected by the first lens appropriately, so that the light trend is in smooth transition. The second lens is in a meniscus shape, so that the distance between the first lens and the second lens is reduced, the physical total length of the lens is shortened, and the miniaturization of the lens is realized.

The third lens can have positive focal power, and the object-side surface and the image-side surface of the third lens can be convex at the same time; or the object side surface is a convex surface, and the image side surface is a concave surface; or the object side surface is concave and the image side surface is convex. The focal power of the third lens is positive, so that spherical aberration and chromatic aberration introduced by the first two lenses can be balanced, and meanwhile, light beams are converged and light rays are compressed.

The fourth 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 according to the embodiment of the present invention is a biconvex lens element, which can converge the diverging light rays and compress the light rays appropriately, so that the light rays smoothly transit and enter the rear optical system.

The fifth lens element can have a positive optical power, and the object-side surface and the image-side surface of the fifth lens element can be convex at the same time. Meanwhile, the sixth lens element can have a negative power, and the object-side surface of the sixth lens element can be concave and the image-side surface can be convex or concave. The fifth lens with positive focal power is arranged in front of the sixth lens with negative focal power, so that the light rays passing through the fourth lens are smoothly transited to the sixth lens, and the total length of the optical system is reduced.

Alternatively, the fifth lens element can have a negative power, and the object-side surface of the fifth lens element is convex and the image-side surface of the fifth lens element is concave. Meanwhile, the sixth lens element may have positive optical power, and both the object-side surface and the image-side surface thereof may be convex. The fifth lens with negative focal power is in front of the fifth lens, and the sixth lens with positive focal power is behind the fifth lens, so that the sixth lens can effectively converge the front divergent light rays.

In an exemplary embodiment, a stop for limiting the light beam may be disposed between the second lens and the third lens or between the third lens and the fourth lens to further improve the imaging quality of the optical lens. The diaphragm is beneficial to effectively collecting light rays entering the optical system, shortening the total length of the system and reducing the aperture of the lens. In the embodiment of the present application, the stop may be provided in the vicinity of the object side surface of the third lens, in the vicinity of the image side surface of the third lens, or in an intermediate position between the third lens and the fourth lens. It should be noted, however, that the locations of the diaphragms disclosed herein 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 sixth lens and the image plane to filter light rays having different wavelengths, as needed. The optical lens according to the present application may further include a protective glass disposed between the sixth lens and the imaging surface to prevent internal elements (e.g., a chip) 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 procedure in the lens manufacturing process.

In an exemplary embodiment, the fifth lens and the sixth lens are cemented to form a cemented lens. Wherein the fifth lens having a positive power is combined with the sixth lens having a negative power, or the fifth lens having a negative power is combined with the sixth lens having a positive power. The gluing method adopted between the lenses has at least one of the following advantages: self color difference is reduced, tolerance sensitivity is reduced, and the integral color difference of the system is balanced through the residual partial color difference; reducing the air space between the two lenses, thereby reducing the overall length of the system; the assembling parts between the lenses are reduced, so that the working procedures are reduced, and the cost is reduced; the tolerance sensitivity problems of inclination/core deviation and the like generated in the assembling process of the lens unit are reduced, and the production yield is improved; the light quantity loss caused by reflection among the lenses is reduced, and the illumination is improved; further reducing the curvature of field and effectively correcting the off-axis point aberration of the optical lens. The gluing design shares the whole chromatic aberration correction of the system, effectively corrects the aberration so as to improve the resolving power, and enables the optical system to be compact as a whole and meet the miniaturization requirement.

In an exemplary embodiment, the first to sixth lenses in the optical lens may each be made of glass. Preferably, at least one of the second lens, the third lens, and the fourth lens is made of glass. The optical lens made of glass can further reduce the front port diameter of the optical system and improve the stability of the system. Preferably, the second lens, the third lens and the fourth lens are all made of glass.

In an exemplary embodiment, the first to sixth lenses in the optical lens may each be made of plastic. The optical lens is made of plastic, so that the manufacturing cost can be effectively reduced.

In an exemplary embodiment, some of the first to sixth lenses in the optical lens may be made of plastic to reduce manufacturing costs.

In an exemplary embodiment, the first lens may be made of a high refractive index material. For example, the refractive index Nd1 of the first lens satisfies: nd1 is more than or equal to 1.65. This choice of material for the first lens is beneficial for reducing the front aperture of the optical system, reducing the angle of incidence of the incident light rays on the face, and facilitating more light rays entering the optical system to increase the luminous flux.

In an exemplary embodiment, a distance TTL on the optical axis from the object side surface of the first lens to the imaging surface of the optical lens and a total effective focal length F of the optical lens satisfy: TTL/F is less than or equal to 10, preferably, TTL/F is less than or equal to 9.5. In the present application, the distance on the optical axis from the object-side surface of the first lens to the imaging surface of the optical lens is also referred to as the total length of the optical lens. The proportional relation between the total length of the optical lens and the total effective focal length is reasonably controlled, and the system miniaturization is favorably realized.

In an exemplary embodiment, a distance BFL on the optical axis from the image-side surface of the sixth lens to the imaging surface of the optical lens and a distance TL on the optical axis from the object-side surface of the first lens to the image-side surface of the sixth lens satisfy: BFL/TL is greater than or equal to 0.1, preferably BFL/TL is greater than or equal to 0.15. In the present application, the distance on the optical axis from the image-side surface of the sixth lens element to the imaging surface of the optical lens is also referred to as the back focal length of the optical lens; the distance on the optical axis from the object-side surface of the first lens to the image-side surface of the sixth lens is also referred to as the lens group length of the optical lens. The proportional relation between the back focal length of the optical lens and the length of the lens group of the optical lens is reasonably controlled, and the assembly of the module 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 FOV, and the image height H corresponding to the maximum field angle FOV satisfy: D/H/FOV is less than or equal to 0.025, preferably, D/H/FOV is less than or equal to 0.02. The mutual relation among the three is reasonably set, the front end caliber of the optical lens is easy to reduce, and miniaturization is realized.

In an exemplary embodiment, a distance d12 between the image side surface of the first lens and the object side surface of the second lens on the optical axis and a distance TTL between the object side surface of the first lens and the imaging surface of the optical lens on the optical axis satisfy: d12/TTL is less than or equal to 0.25, and preferably, d12/TTL is less than or equal to 0.2. In this application, the distance between the image side surface of the first lens and the object side surface of the second lens on the optical axis may also be referred to as an air space between the first lens and the second lens. The air interval between the first lens and the second lens is reasonably reduced, and the optical caliber of the first lens is favorably reduced.

In an exemplary embodiment, a distance d34 between the image-side surface of the third lens and the object-side surface of the fourth lens on the optical axis and a total effective focal length F of the optical lens satisfy: d34/F is less than or equal to 0.95, preferably, d34/F is less than or equal to 0.8. In the present application, the distance between the image-side surface of the third lens and the object-side surface of the fourth lens on the optical axis may also be referred to as an air space between the third lens and the fourth lens. The air space between the third lens and the fourth lens is reasonably reduced, and large-angle light rays are favorably collected to a rear optical system.

In an exemplary embodiment, the effective focal length F5 of the fifth lens and the effective focal length F6 of the sixth lens satisfy: 0.5. Ltoreq. F5/F6. Ltoreq.1.5, preferably 0.8. Ltoreq. F5/F6. Ltoreq.1.3. The proportional relation between the effective focal length of the fifth lens and the effective focal length of the sixth lens is reasonably set, the effective focal length of the fifth lens is close to that of the sixth lens, and smooth transition of optics is facilitated.

In an exemplary embodiment, the maximum field angle FOV of the optical lens, the total effective focal length F of the optical lens, and the image height H corresponding to the maximum field angle FOV satisfy: (FOV XF)/H.gtoreq.45, preferably (FOV XF)/H.gtoreq.50. The mutual relation of the three is reasonably set, and the optical lens is favorable for having both large field angle and long-focus characteristic.

In an exemplary embodiment, the effective focal length F4 of the fourth lens and the radius of curvature R41 of the object side surface of the fourth lens satisfy: 0.1. Ltoreq. F4/R41. Ltoreq.1.2, preferably 0.3. Ltoreq. F4/R41. Ltoreq.1. The proportional relation between the effective focal length of the fourth lens and the curvature radius of the object side surface of the fourth lens is reasonably set, so that the fourth lens better converges the front light, the rear end caliber of the lens is favorably reduced, and the size of the lens is reduced.

In an exemplary embodiment, the radius of curvature R11 of the object-side surface of the first lens and the radius of curvature R21 of the object-side surface of the second lens satisfy: R11/R21| ≧ 0.15, preferably R11/R21| ≧ 0.2. The proportional relation between the curvature radius of the object side surface of the first lens and the curvature radius of the object side surface of the second lens is reasonably set, the special limitation of the curvature radius of the object side surface of the first lens and the curvature radius of the object side surface of the second lens is realized, and the transition of the large-angle light rays collected by the first lens to a rear optical system by the second lens is facilitated.

In an exemplary embodiment, the effective focal length F2 of the second lens and the total effective focal length F of the optical lens satisfy: -5. Ltoreq. F2/F. Ltoreq.1.5, preferably-4.5. Ltoreq. F2/F. Ltoreq.2. The ratio of the effective focal length of the second lens to the total effective focal length of the optical lens is set within a reasonable numerical range, so that the light passing through the first lens can be effectively converged, and the aberration of the system can be balanced.

In an exemplary embodiment, a distance D13 on the optical axis from the object-side surface of the first lens to the image-side surface of the third lens satisfies, with the total effective focal length of the optical lens: D13/F is more than or equal to 3 and less than or equal to 6. The distance from the object side surface of the first lens to the image side surface of the third lens on the optical axis is reasonably set, the small distance is not favorable for realizing a large field angle by the lens, the large distance is not favorable for reducing the overall length of the system, and the miniaturization of the lens is realized.

In an exemplary embodiment, each of the first to sixth lenses may be an aspherical lens, and preferably, at least one lens of the second, third, and fourth lenses may be an aspherical lens. 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 better curvature radius characteristics, and has 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. The aspheric lens helps to correct system aberration and improve resolving power. Preferably, the second lens, the third lens and the fourth lens are all aspheric lenses.

According to the optical lens of the embodiment of the application, the shape of the lens is set through optimization, the focal power is distributed reasonably, the number of spherical and aspheric mirror surfaces is set properly, and high-definition imaging can be achieved. Meanwhile, the requirements of miniaturization, small distortion, high image resolution, low cost, good temperature adaptability and the like of the lens can be met. The vehicle-mounted side-looking lens meets the application requirements of miniaturization and high resolution. On this basis, the fifth lens and the sixth lens in the optical lens are mutually matched, so that the influence of temperature change on the focal length of the lens can be effectively compensated, and the stability of the resolution of the lens at different temperatures can be further improved.

However, it will be appreciated by those skilled in the art that the number of lenses constituting the lens barrel may be varied to achieve the various results and advantages described in the present specification without departing from the claimed subject matter. For example, although six lenses are exemplified in the embodiment, the optical lens is not limited to include six 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 assembly 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, a fifth lens element L5 and a sixth lens element L6.

The first lens element L1 is a meniscus lens element with negative power, and has a convex object-side surface S1 and a concave image-side surface S2. The second lens element L2 is a meniscus lens element with negative power, and has a convex object-side surface S3 and a concave image-side surface S4. The third lens element L3 is a meniscus lens element with positive refractive power, and has a convex object-side surface S5 and a concave image-side surface S6. The fourth lens element L4 is a biconvex lens element with positive refractive power, and has a convex object-side surface S8 and a convex image-side surface S9. The fifth lens element L5 is a biconvex lens element with positive refractive power, and has a convex object-side surface S10 and a convex image-side surface S11. The sixth lens element L6 is a meniscus lens element with negative refractive power, and has a concave object-side surface S11 and a convex image-side surface S12. The fifth lens L5 and the sixth lens L6 may be cemented to constitute a cemented lens.

The optical lens may further include a stop STO, which may be disposed between the third lens L3 and the fourth lens L4 to improve imaging quality.

In the present embodiment, the object-side surface and the image-side surface of the second lens L2, the third lens L3, and the fourth lens L4 may be aspheric.

Optionally, the optical lens may further include a filter L7 and/or a protective glass L7 'having an object side surface S13 and an image side surface S14, the filter L7 may be used to correct color deviation and the protective glass L7' may be used to protect the image sensing chip IMA located at the imaging plane. The light from the object passes through the respective surfaces S1 to S14 in order and is finally imaged on the imaging plane.

Table 1 shows a radius of curvature R, a thickness T (it is understood that the thickness T of the row on which S1 is located is the center thickness of the first lens L1, the thickness T of the row on which S2 is located is the air interval d12 between the first lens L1 and the second lens L2, and so on), a refractive index Nd, and an abbe number Vd of each lens of the optical lens of example 1.

TABLE 1

The present embodiment adopts six lenses as an example, and by reasonably allocating 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 front end aperture, small CRA, good temperature performance, 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 =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 and E are all high-order coefficient. Table 2 below shows conic coefficients K and high-order term coefficients a, B, C, D, and E that can be used for the aspherical lens surfaces S3, S4, S5, S6, S8, and S9 in example 1.

TABLE 2

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 assembly 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, a fifth lens element L5 and a sixth lens element L6.

The first lens element L1 is a meniscus lens element with negative refractive power, and has a convex object-side surface S1 and a concave image-side surface S2. The second lens element L2 is a meniscus lens element with negative power, and has a convex object-side surface S3 and a concave image-side surface S4. The third lens element L3 is a meniscus lens element with positive refractive power, and has a convex object-side surface S5 and a concave image-side surface S6. The fourth lens element L4 is a biconvex lens element with positive refractive power, and has a convex object-side surface S8 and a convex image-side surface S9. The fifth lens element L5 is a biconvex lens element with positive refractive power, and has a convex object-side surface S10 and a convex image-side surface S11. The sixth lens element L6 is a meniscus lens element with negative refractive power, and has a concave object-side surface S11 and a convex image-side surface S12. The fifth lens L5 and the sixth lens L6 may be cemented to constitute a cemented lens.

Table 3 shows the radius of curvature R, thickness T, refractive index Nd, and abbe number Vd of each lens of the optical lens of example 2.

TABLE 3

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 S3, S4, S5, S6, S8, and S9 in example 2 are given in table 4 below.

Flour mark

K

A

B

C

D

E

S3

78.6170

6.3702E-04

-5.0156E-05

3.8591E-06

-1.6503E-07

1.1474E-10

S4

-3.0014

1.9146E-03

-1.1020E-04

1.4193E-05

4.5627E-09

S5

0.0000

-9.4403E-04

-2.2489E-05

-4.4364E-07

2.3204E-08

-1.7659E-08

S6

0.0000

-5.6656E-05

3.3008E-04

-5.9796E-06

-4.9668E-06

8.9334E-07

S8

-19.5027

6.0975E-04

-1.9600E-04

2.5949E-05

-6.2876E-06

2.9427E-07

S9

0.6484

5.7100E-04

-2.1554E-04

1.1512E-05

1.4274E-06

-5.1229E-07

TABLE 4

Example 3

An optical lens according to embodiment 3 of the present application is described below with reference to fig. 3. 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 assembly 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, a fifth lens element L5 and a sixth lens element L6.

The first lens element L1 is a meniscus lens element with negative refractive power, and has a convex object-side surface S1 and a concave image-side surface S2. The second lens element L2 is a meniscus lens element with negative power, and has a convex object-side surface S3 and a concave image-side surface S4. The third lens element L3 is a biconvex lens element with positive refractive power, and has a convex object-side surface S6 and a convex image-side surface S7. The fourth lens element L4 is a biconvex lens element with positive refractive power, and has a convex object-side surface S8 and a convex image-side surface S9. The fifth lens element L5 is a meniscus lens element with negative power, and has a convex object-side surface S10 and a concave image-side surface S11. The sixth lens element L6 is a biconvex lens with positive refractive power, and has a convex object-side surface S11 and a convex image-side surface S12. The fifth lens L5 and the sixth lens L6 may be cemented to constitute a cemented lens.

The optical lens may further include a stop STO, which may be disposed between the second lens L2 and the third lens L3 to improve imaging quality. For example, the stop STO may be disposed near the object side surface S6 of the third lens L3.

Table 5 shows the radius of curvature R, thickness T, refractive index Nd, and abbe number Vd of each lens of the optical lens of example 3.

TABLE 5

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 S3, S4, S6, S7, S8, and S9 in example 3 are given in table 6 below.

Flour mark

K

A

B

C

D

E

S3

77.5000

-1.3345E-03

1.3952E-04

-6.0545E-06

6.6498E-08

-6.8719E-10

S4

-2.9500

3.0909E-03

1.0970E-04

1.1738E-05

-2.3558E-07

-1.4616E-08

S6

0.0000

-1.9562E-04

4.6192E-05

1.8145E-06

-3.4883E-07

-2.0534E-22

S7

0.0000

4.6803E-04

2.5874E-04

-1.7397E-05

4.4622E-07

-8.2612E-23

S8

-19.2000

1.4036E-03

7.4270E-05

-8.4172E-06

9.5068E-08

7.1427E-09

S9

0.3500

1.4380E-03

1.8964E-05

2.8519E-06

-2.1881E-08

3.6344E-09

TABLE 6

Example 4

An optical lens according to embodiment 4 of the present application is described below with reference to fig. 4. 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 assembly 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, a fifth lens element L5 and a sixth lens element L6.

The first lens element L1 is a meniscus lens element with negative refractive power, and has a convex object-side surface S1 and a concave image-side surface S2. The second lens element L2 is a meniscus lens element with negative power, and has a convex object-side surface S3 and a concave image-side surface S4. The third lens element L3 is a biconvex lens element with positive refractive power, and has a convex object-side surface S6 and a convex image-side surface S7. The fourth lens element L4 is a biconvex lens with positive refractive power, and has a convex object-side surface S8 and a convex image-side surface S9. The fifth lens element L5 is a meniscus lens element with negative power, and has a convex object-side surface S10 and a concave image-side surface S11. The sixth lens element L6 is a biconvex lens with positive refractive power, and has a convex object-side surface S11 and a convex image-side surface S12. The fifth lens L5 and the sixth lens L6 may be cemented to constitute a cemented lens.

Table 7 shows the radius of curvature R, thickness T, refractive index Nd, and abbe number Vd of each lens of the optical lens of example 4.

TABLE 7

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 S3, S4, S6, S7, S8, and S9 in example 4 are given in table 8 below.

TABLE 8

Example 5

An optical lens according to embodiment 5 of the present application is described below with reference to fig. 5. Fig. 5 shows a schematic structural diagram of an optical lens according to embodiment 5 of the present application.

As shown in fig. 5, the optical lens assembly 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, a fifth lens element L5 and a sixth lens element L6.

The first lens element L1 is a meniscus lens element with negative power, and has a convex object-side surface S1 and a concave image-side surface S2. The second lens element L2 is a meniscus lens element with negative power, and has a convex object-side surface S3 and a concave image-side surface S4. The third lens element L3 is a meniscus lens element with positive refractive power, and has a concave object-side surface S5 and a convex image-side surface S6. The fourth lens element L4 is a biconvex lens element with positive refractive power, and has a convex object-side surface S8 and a convex image-side surface S9. The fifth lens element L5 is a meniscus lens element with negative power, and has a convex object-side surface S10 and a concave image-side surface S11. The sixth lens element L6 is a biconvex lens with positive refractive power, and has a convex object-side surface S11 and a convex image-side surface S12. The fifth lens L5 and the sixth lens L6 may be cemented to constitute a cemented lens.

In the present embodiment, the object-side and image-side surfaces of the second lens L2 and the third lens L3 and the image-side surface of the sixth lens L6 may be aspheric.

Table 9 shows the radius of curvature R, thickness T, refractive index Nd, and abbe number Vd of each lens of the optical lens of example 5.

TABLE 9

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 S3, S4, S5, S6, and S12 in example 5 are given in table 10 below.

Flour mark

K

A

B

C

D

E

S3

78.6300

4.1731E-04

-1.6196E-05

6.2504E-06

-2.7029E-07

-5.8719E-10

S4

-3.0000

4.3961E-03

6.3969E-05

9.8622E-06

3.3007E-05

-2.4616E-08

S5

0.0000

-1.3610E-03

5.7756E-05

4.2944E-06

4.3208E-07

-3.0423E-20

S6

0.0000

1.6709E-04

1.7685E-05

-5.2253E-07

9.9420E-08

-6.9210E-22

S12

0.0000

4.9112E-04

-4.6558E-05

6.5046E-06

-3.6088E-07

-5.6903E-22

Watch 10

Example 6

An optical lens according to embodiment 6 of the present application is described below with reference to fig. 6. Fig. 6 shows a schematic structural diagram of an optical lens according to embodiment 6 of the present application.

As shown in fig. 6, the optical lens assembly 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, a fifth lens element L5 and a sixth lens element L6.

The first lens element L1 is a meniscus lens element with negative refractive power, and has a convex object-side surface S1 and a concave image-side surface S2. The second lens element L2 is a meniscus lens element with negative power, and has a convex object-side surface S3 and a concave image-side surface S4. The third lens element L3 is a meniscus lens element with positive refractive power, and has a concave object-side surface S5 and a convex image-side surface S6. The fourth lens element L4 is a biconvex lens element with positive refractive power, and has a convex object-side surface S8 and a convex image-side surface S9. The fifth lens element L5 is a meniscus lens element with negative power, and has a convex object-side surface S10 and a concave image-side surface S11. The sixth lens element L6 is a biconvex lens with positive refractive power, and has a convex object-side surface S11 and a convex image-side surface S12. The fifth lens L5 and the sixth lens L6 may be cemented to constitute a cemented lens.

Table 11 shows the radius of curvature R, thickness T, refractive index Nd, and abbe number Vd of each lens of the optical lens of example 6.

TABLE 11

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 S3, S4, S5, S6, and S12 in example 4 are given in table 12 below.

Flour mark

K

A

B

C

D

E

S3

114.1258

8.7308E-04

-2.9957E-05

5.3600E-06

-2.4657E-07

1.1436E-09

S4

-4.3841

3.7546E-03

8.7031E-06

5.7623E-07

8.7783E-07

-4.4786E-08

S5

200.0000

-1.2613E-03

-4.7255E-06

3.9324E-06

8.4030E-07

-2.6570E-08

S6

-0.0200

1.6353E-04

3.8657E-05

-1.2184E-06

-2.4758E-07

1.5525E-08

S12

-0.2000

5.1512E-04

-5.0750E-05

6.8551E-06

-4.6322E-07

5.9314E-10

TABLE 12

Example 7

An optical lens according to embodiment 7 of the present application is described below with reference to fig. 7. Fig. 7 shows a schematic structural diagram of an optical lens according to embodiment 7 of the present application.

As shown in fig. 7, the optical lens assembly 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, a fifth lens element L5 and a sixth lens element L6.

The first lens element L1 is a meniscus lens element with negative power, and has a convex object-side surface S1 and a concave image-side surface S2. The second lens element L2 is a meniscus lens element with positive power, the object-side surface S3 being concave and the image-side surface S4 being convex. The third lens element L3 is a meniscus lens element with positive refractive power, and has a convex object-side surface S5 and a concave image-side surface S6. The fourth lens element L4 is a biconvex lens element with positive refractive power, and has a convex object-side surface S8 and a convex image-side surface S9. The fifth lens element L5 is a biconvex lens element with positive refractive power, and has a convex object-side surface S10 and a convex image-side surface S11. The sixth lens element L6 is a biconcave lens element having a negative refractive power, and has a concave object-side surface S11 and a concave image-side surface S12. The fifth lens L5 and the sixth lens L6 may be cemented to constitute a cemented lens.

The optical lens may further include a stop STO, which may be disposed between the third lens L3 and the fourth lens L4 to improve imaging quality. For example, the stop STO may be disposed near the image-side surface S6 of the third lens L3.

Table 13 shows the radius of curvature R, thickness T, refractive index Nd, and abbe number Vd of each lens of the optical lens of example 7.

Watch 13

The following table 14 shows conic coefficients K and high-order term coefficients a, B, C, D, and E that can be used for the aspherical lens surfaces S3, S4, S5, S6, S8, and S9 in example 7.

Flour mark

K

A

B

C

D

E

S3

0.0000

1.8103E-03

-4.0662E-06

-3.0996E-07

2.1777E-09

2.0743E-21

S4

0.0000

1.9680E-03

-3.2494E-05

6.6869E-07

-2.4507E-08

1.6023E-24

S5

0.0000

8.6734E-04

4.6259E-05

4.9676E-06

-5.1677E-07

-2.6677E-25

S6

0.0000

7.7522E-04

4.2506E-04

3.1769E-05

6.5577E-07

-1.6420E-25

S8

0.0000

-4.6372E-04

1.1757E-04

1.7060E-05

-4.8339E-07

3.7523E-28

S9

0.0000

8.2846E-05

5.8755E-05

-1.0417E-05

1.0569E-07

1.8690E-26

TABLE 14

Example 8

An optical lens according to embodiment 8 of the present application is described below with reference to fig. 8. Fig. 8 shows a schematic structural diagram of an optical lens according to embodiment 8 of the present application.

As shown in fig. 8, the optical lens assembly 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, a fifth lens element L5 and a sixth lens element L6.

The first lens element L1 is a meniscus lens element with negative refractive power, and has a convex object-side surface S1 and a concave image-side surface S2. The second lens element L2 is a meniscus lens element with positive power, the object-side surface S3 being concave and the image-side surface S4 being convex. The third lens element L3 is a meniscus lens element with positive refractive power, and has a convex object-side surface S5 and a concave image-side surface S6. The fourth lens element L4 is a biconvex lens element with positive refractive power, and has a convex object-side surface S8 and a convex image-side surface S9. The fifth lens element L5 is a biconvex lens element with positive refractive power, and has a convex object-side surface S10 and a convex image-side surface S11. The sixth lens element L6 is a biconcave lens element having negative refractive power, and has a concave object-side surface S11 and a concave image-side surface S12. The fifth lens L5 and the sixth lens L6 may be cemented to constitute a cemented lens.

Table 15 shows the radius of curvature R, thickness T, refractive index Nd, and abbe number Vd of each lens of the optical lens of example 8.

Watch 15

The following table 16 shows conic coefficients K and high-order term coefficients a, B, C, D, and E that can be used for the aspherical lens surfaces S3, S4, S5, S6, S8, and S9 in example 8.

Flour mark

K

A

B

C

D

E

S3

-0.3200

1.7720E-03

-4.0662E-06

-7.2005E-07

1.0976E-09

2.6288E-10

S4

0.2500

1.9958E-03

-3.4966E-05

3.8539E-07

-1.2565E-08

1.3403E-09

S5

0.1250

9.2861E-04

1.8828E-05

1.9315E-06

-3.9680E-06

2.2907E-09

S6

-0.1300

6.6645E-04

4.6328E-04

4.6251E-05

1.2112E-06

-5.3510E-08

S8

0.0500

-4.8457E-04

2.1900E-04

3.4737E-05

7.5330E-07

-1.6788E-07

S9

-0.0400

7.3658E-05

5.8755E-05

-1.1632E-05

1.2777E-05

7.8540E-08

TABLE 16

In summary, examples 1 to 8 each satisfy the relationship shown in table 17 below. In table 17, TTL, F, BFL, D, TL, H, R11, R21, R41, D12, D23, D34, D13, F2, F4, F5, F6 are in units of millimeters (mm), and FOV is in units of degrees (°).

TABLE 17

The present application also provides an electronic device that may include the optical lens according to the above-described embodiments of the present application and an imaging element for converting an optical image formed by the optical lens into an electrical signal. The electronic device may be a stand-alone electronic device such as a range finding camera or may be an imaging module integrated on a device such as a range finding device. Furthermore, the electronic device may also be a stand-alone imaging device such as a vehicle-mounted camera, or may be an imaging module integrated on a driving assistance system such as a car.

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 according to the present application is not limited to the specific combination of the above-mentioned features, but also covers other embodiments where any combination of the above-mentioned features or their equivalents is made 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. An optical lens, in order from an object side to an image side along an optical axis, comprising: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens, wherein:

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 optical power;

the third lens has positive optical power;

the fourth lens has positive focal power, the object side surface of the fourth lens is a convex surface, and the image side surface of the fourth lens is a convex surface;

the fifth lens has optical power; and

the sixth lens has optical power;

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 FOV and the image height H corresponding to the maximum field angle FOV satisfy: D/H/FOV is more than or equal to 2.07 and less than or equal to 4.5 multiplied by 180 degrees.

2. The optical lens assembly as claimed in claim 1, wherein the second lens element has a negative refractive power, and the object-side surface of the second lens element is convex and the image-side surface of the second lens element is concave.

3. The optical lens assembly as claimed in claim 1, wherein the second lens element has a positive optical power, and the second lens element has a concave object-side surface and a convex image-side surface.

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

5. An optical lens system as recited in claim 1, wherein the third lens element has a convex object-side surface and a convex image-side surface.

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

7. The optical lens assembly as claimed in claim 1, wherein the optical power of the fifth lens element is positive optical power, and the object-side surface and the image-side surface of the fifth lens element are convex surfaces.

8. The optical lens barrel according to claim 1, wherein the power of the fifth lens element is negative, and the object-side surface of the fifth lens element is convex and the image-side surface of the fifth lens element is concave.

9. The optical lens assembly as claimed in claim 1, wherein the power of the sixth lens element is positive power, and the object-side surface and the image-side surface of the sixth lens element are convex.

10. The optical lens of claim 1, wherein the power of the sixth lens element is negative, and the object-side surface and the image-side surface of the sixth lens element are concave.

11. The optical lens barrel according to claim 1, wherein the power of the sixth lens element is negative, and the object-side surface of the sixth lens element is concave and the image-side surface thereof is convex.

12. An optical lens according to claim 1, wherein the fifth lens and the sixth lens are cemented to form a cemented lens.

13. An optical lens according to claim 1, wherein at least two lenses of the first lens to the sixth lens are aspherical lenses.

14. An optical lens according to claim 1, wherein the second lens, the third lens and the fourth lens are all aspheric lenses.

15. An optical lens barrel according to any one of claims 1 to 14, wherein a distance TTL between an object side surface of the first lens element and an image plane of the optical lens on the optical axis and a total effective focal length F of the optical lens satisfy:

TTL/F≤10。

16. an optical lens barrel according to any one of claims 1 to 14, wherein a distance BFL on the optical axis from an image-side surface of the sixth lens element to an image plane of the optical lens barrel and a distance TL on the optical axis from an object-side surface of the first lens element to an image-side surface of the sixth lens element satisfy:

BFL/TL≥0.1。

17. an optical lens barrel according to any one of claims 1 to 14, wherein a distance d12 between an image side surface of the first lens element and an object side surface of the second lens element on the optical axis and a distance TTL between the object side surface of the first lens element and an image plane of the optical lens on the optical axis satisfy:

d12/TTL≤0.25。

18. an optical lens barrel according to any one of claims 1 to 14, wherein a distance d34 between an image side surface of the third lens and an object side surface of the fourth lens on the optical axis and a total effective focal length F of the optical lens satisfy:

d34/F≤0.95。

19. an optical lens according to any one of claims 1 to 14, characterized in that the effective focal length F5 of the fifth lens and the effective focal length F6 of the sixth lens satisfy:

0.5≤|F5/F6|≤1.5。

20. an optical lens according to any of claims 1-14, characterized in that the maximum field angle FOV of the optical lens, the total effective focal length F of the optical lens and the image height H corresponding to the maximum field angle FOV satisfy:

(FOV×F)/H≥45°。

21. an optical lens barrel according to any one of claims 1 to 14, wherein an effective focal length F4 of the fourth lens and a radius of curvature R41 of an object side surface of the fourth lens satisfy:

0.1≤|F4/R41|≤1.2。

22. an optical lens barrel according to any one of claims 1 to 14, wherein a radius of curvature R11 of the object side surface of the first lens and a radius of curvature R21 of the object side surface of the second lens satisfy:

|R11/R21|≥0.15。

23. an optical lens according to claim 2, characterized in that the effective focal length F2 of the second lens and the total effective focal length F of the optical lens satisfy:

-5≤F2/F≤-1.5。

24. an optical lens, in order from an object side to an image side along an optical axis, comprising: first lens, second lens, third lens, fourth lens, fifth lens and sixth lens, characterized in that:

the first lens has a negative focal power;

the second lens has optical power;

the third lens has positive optical power;

the fourth lens has positive optical power;

the fifth lens has optical power; and

the sixth lens has an optical power, wherein:

the distance d34 between the image side surface of the third lens and the object side surface of the fourth lens on the optical axis and the total effective focal length F of the optical lens satisfy that: d34/F is less than or equal to 0.95; and

25. An optical lens barrel according to claim 24, wherein the first lens element has a convex object-side surface and a concave image-side surface.

26. An optical lens barrel according to claim 24, wherein the fourth lens element has a convex object-side surface and a convex image-side surface.

27. An optical lens as recited in claim 24, wherein the second lens element has a negative optical power, and wherein the second lens element has a convex object-side surface and a concave image-side surface.

28. An optical lens as recited in claim 24, wherein the optical power of the second lens element is positive, and the object-side surface of the second lens element is concave and the image-side surface of the second lens element is convex.

29. An optical lens barrel according to claim 24, wherein the third lens element has a convex object-side surface and a concave image-side surface.

30. An optical lens barrel according to claim 24, wherein the third lens element has a convex object-side surface and a convex image-side surface.

31. An optical lens barrel according to claim 24, wherein the third lens element has a concave object-side surface and a convex image-side surface.

32. An optical lens as claimed in claim 24, wherein the optical power of the fifth lens element is positive optical power, and the object-side surface and the image-side surface of the fifth lens element are convex.

33. An optical lens barrel according to claim 24, wherein the optical power of the fifth lens element is negative, and the object-side surface of the fifth lens element is convex and the image-side surface of the fifth lens element is concave.

34. The optical lens assembly as recited in claim 24, wherein the power of the sixth lens element is positive power, and the object-side surface and the image-side surface of the sixth lens element are convex.

35. An optical lens barrel according to claim 24, wherein the power of the sixth lens element is negative, and the object-side surface and the image-side surface of the sixth lens element are concave.

36. An optical lens barrel according to claim 24, wherein the power of the sixth lens element is negative, and the object-side surface of the sixth lens element is concave and the image-side surface thereof is convex.

37. An optical lens according to claim 24, characterized in that the fifth lens and the sixth lens are cemented to form a cemented lens.

38. An optical lens barrel according to claim 24, wherein at least two lenses of the first lens to the sixth lens are aspherical lenses.

39. An optical lens barrel according to claim 24, wherein the second lens, the third lens and the fourth lens are all aspheric lenses.

40. An optical lens element according to any one of claims 24 to 39, wherein a distance TTL between an object side surface of the first lens element and an image plane of the optical lens element on the optical axis and a total effective focal length F of the optical lens element satisfy:

TTL/F≤10。

41. an optical lens element according to any one of claims 24 to 39, wherein a distance BFL on the optical axis from an image-side surface of the sixth lens element to an image plane of the optical lens element and a distance TL on the optical axis from an object-side surface of the first lens element to an image-side surface of the sixth lens element satisfy:

BFL/TL≥0.1。

42. an optical lens element according to any one of claims 24 to 39, wherein a distance d12 between an image-side surface of the first lens element and an object-side surface of the second lens element on the optical axis and a distance TTL between the object-side surface of the first lens element and an image plane of the optical lens element on the optical axis satisfy:

d12/TTL≤0.25。

43. an optical lens element according to any of claims 24-39, characterized in that the effective focal length F5 of the fifth lens element and the effective focal length F6 of the sixth lens element satisfy:

0.5≤|F5/F6|≤1.5。

44. an optical lens as claimed in any one of claims 24 to 39, characterized in that the maximum field angle FOV of the optical lens, the total effective focal length F of the optical lens and the image height H corresponding to the maximum field angle FOV satisfy:

(FOV×F)/H≥45°。

45. an optical lens element according to any one of claims 24-39, characterized in that the effective focal length F4 of the fourth lens element and the radius of curvature R41 of the object side of the fourth lens element satisfy:

0.1≤|F4/R41|≤1.2。

46. an optical lens element according to any one of claims 24 to 39, wherein the radius of curvature R11 of the object side surface of the first lens element and the radius of curvature R21 of the object side surface of the second lens element satisfy:

|R11/R21|≥0.15。

47. an optical lens according to claim 27, characterized in that the effective focal length F2 of the second lens and the total effective focal length F of the optical lens satisfy:

-5≤F2/F≤-1.5。

48. an electronic apparatus, characterized by comprising the optical lens according to claim 1 or 24 and an imaging element for converting an optical image formed by the optical lens into an electrical signal.