CN109581635B

CN109581635B - Optical lens

Info

Publication number: CN109581635B
Application number: CN201710909483.0A
Authority: CN
Inventors: 姚波; 王东方; 谢前森
Original assignee: Ningbo Sunny Automotive Optech Co Ltd
Current assignee: Ningbo Sunny Automotive Optech Co Ltd
Priority date: 2017-09-29
Filing date: 2017-09-29
Publication date: 2021-07-30
Anticipated expiration: 2037-09-29
Also published as: CN109581635A

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 and the third lens can both have negative focal power; the second lens, the fourth lens and the fifth lens can all have positive focal power, wherein the object side surfaces of the first lens and the third lens can be convex surfaces, and the image side surfaces of the first lens and the third lens can be concave surfaces; the object side surface and the image side surface of the second lens, the fourth lens and the fifth lens can be convex surfaces; and the third lens may be cemented with the fourth lens.

Description

Optical lens

Technical Field

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

Background

At present, due to different installation positions, the focusing functions of the vehicle-mounted lens are different. For example, a forward-looking lens needs to be able to view objects at a long distance (long focal length), while a rear/side-looking lens needs to be able to view the surroundings in a wide angle range around the vehicle (wide angle of view, wide angle).

For a conventional vehicle-mounted lens currently applied, the following general conditions are available:

firstly, in order to detect a front distant-direction object, a traditional front-view lens is limited in the field angle, and the field angle is usually small (namely, the field angle is seen far, the focal length is long, and therefore the field angle visible range is small);

secondly, the common vehicle-mounted wide-angle lens, such as a rear view lens and a side view lens, usually causes a short focal length in order to expand the field range;

the conventional forward-looking lens is characterized by a long-focus small field range and is used for capturing and observing long-distance objects, the integral observation field is expanded, and the wide-angle lens with a short focus and a large field angle range is matched, so that the picture splicing is completed together by combining software.

Therefore, it is necessary to design an optical lens that is compatible with the functions of a telephoto lens and a short-focus lens, and has a large aperture, a large field angle, and a high resolution, so as to replace the conventional single-function multi-lens in the driving system.

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 and the third lens can both have negative focal power; the second lens, the fourth lens and the fifth lens can all have positive focal power, wherein the object side surfaces of the first lens and the third lens can be convex surfaces, and the image side surfaces of the first lens and the third lens can be concave surfaces; the object side surface and the image side surface of the second lens, the fourth lens and the fifth lens can be convex surfaces; and the third lens may be cemented with the fourth lens.

In one embodiment, the first lens may be an aspheric lens.

In one embodiment, the difference between the focal length value F1 of the first lens and the focal length value F of the whole group of optical lenses can satisfy | F1/F | ≧ 1.2.

In one embodiment, a radius of curvature R1 of the object-side surface of the first lens, a radius of curvature R2 of the image-side surface of the first lens, and a distance d1 of the first lens on the optical axis may satisfy: R1/(R2+ d1) is more than or equal to 0.6 and less than or equal to 1.4.

In one embodiment, a distance TTL between a center of an object side surface of the first lens element and an imaging surface of the optical lens on an optical axis and a full-group focal length value F of the optical lens may satisfy: TTL/F is less than or equal to 5.

In one embodiment, the maximum field angle FOvm of the optical lens, the entire group focal length value F of the optical lens, and the image height Ym corresponding to the maximum field angle of the optical lens satisfy (FOvm × F)/Ym ≧ 65.

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 and the third lens may each have a negative optical power, and the second lens, the fourth lens, and the fifth lens may each have a positive optical power, wherein a radius of curvature R1 of an object-side surface of the first lens, a radius of curvature R2 of an image-side surface of the first lens, and a distance d1 of the first lens on the optical axis may satisfy: R1/(R2+ d1) is more than or equal to 0.6 and less than or equal to 1.4.

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

In one embodiment, the object side surface and the image side surface of the second lens, the fourth lens and the fifth lens may be convex.

In one embodiment, the third lens may be cemented with the fourth lens.

In one embodiment, the first lens may be an aspheric lens.

In one embodiment, the optical lens may further include a stop disposed between the second lens and the third lens.

Another 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 includes a first lens, a second lens, a third lens, a fourth lens and a fifth lens. The first lens and the third lens can both have negative focal power; the second lens, the fourth lens and the fifth lens can all have positive focal power; the third lens may be cemented with the fourth lens; and the maximum field angle FOvm of the optical lens, the whole group of focal length values F of the optical lens and the image height Ym corresponding to the maximum field angle of the optical lens can satisfy that (FOvm multiplied by F)/Ym is not less than 65.

In one embodiment, the first lens may be an aspheric lens.

The optical lens adopts five lenses, 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 the beneficial effects of large aperture, high pixel, large field angle, long integral focal length and large angular resolution in the central area of the optical lens are 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; and

fig. 2 is a schematic view showing a structure of an optical lens according to embodiment 2 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 adopts a shape close to a concentric circle, the object side surface is a convex surface, the image side surface is a concave surface, and the effect of central large-angle resolution can be realized. The optical lens can be manufactured by satisfying the following requirements among the radius of curvature R1 of the object-side surface of the first lens, the radius of curvature R2 of the image-side surface of the first lens, and the distance d1 of the first lens on the optical axis: 0.6. ltoreq. R1/(R2+ d 1). ltoreq.1.4, more specifically, R1, R2 and d1 further satisfy 0.9. ltoreq. R1/(R2+ d 1). ltoreq.1, and the object of arranging the first lens so as to be approximately concentric circles can be achieved. The first lens can collect light rays with large angles as much as possible and can disperse the collected light rays. In practical application, considering the outdoor installation and use environment of the vehicle-mounted lens, the vehicle-mounted lens can be in severe weather such as rain and snow, the first lens is arranged in the meniscus shape with the convex surface facing the object side, so that water drops and the like can slide off, and the influence on the imaging quality of the lens is reduced.

The second lens can have positive optical power, and both the object side surface and the image side surface of the second lens can be convex. The second lens can further converge the light collected by the first lens, and adjust the light, so that the light trend is stably transited to the rear optical system, and the aperture of the optical lens is favorably reduced.

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

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 positive optical power, and can have a convex object-side surface and a convex image-side surface.

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 third lens and the fourth lens may be combined into a cemented lens by cementing the image-side surface of the third lens with the object-side surface of the fourth lens. By introducing the cemented lens consisting of the third lens and the fourth lens, the chromatic aberration influence can be eliminated, and the tolerance sensitivity of the system is reduced; meanwhile, the cemented third lens and fourth lens may also have a residual partial chromatic aberration to balance the entire chromatic aberration of the optical system. The gluing of the third lens and the fourth lens omits the air space between the third lens and the fourth lens, so that the whole optical system is compact, and the requirement of system miniaturization is met. Moreover, the gluing of the third lens and the fourth lens can reduce tolerance sensitivity problems of inclination/decentration and the like of the lens unit caused in the assembling process.

In an exemplary embodiment, a stop for limiting the light beam may be disposed between, for example, the second lens and the third lens to further improve the imaging quality of the lens. When the diaphragm is arranged between the second lens and the third lens, incident light rays can be shrunk, the aperture of the lens can be reduced, and the effect of balancing the aperture of the front end and the aperture of the rear end of the whole lens can be achieved.

In the cemented lens, the third lens close to the object side has negative focal power, and the fourth lens close to the image side has positive focal power, so that the light rays passing through the front diaphragm are favorably diverged and converged, the light rays are smoothly transited to the fifth lens, the total length of the optical system is favorably shortened, the short TTL is realized, and the miniaturization characteristic is realized.

In an embodiment, the fifth lens converges light, so as to appropriately increase distortion of the edge of the lens, so that the light with a large angle can reach a chip with a limited size, that is, large-angle imaging of the lens is realized.

In an exemplary embodiment, between the focal length value F1 of the first lens and the entire set of focal length values F of the optical lens, F1/F | ≧ 1.2 may be satisfied, and more specifically, F1 and F may further satisfy | F1/F | ≧ 1.4.

In an exemplary embodiment, a total optical length TTL of the optical lens (i.e., a distance on an optical axis from a center of an object side surface of the first lens to an imaging surface of the optical lens) and a total group focal length value F of the optical lens may satisfy TTL/F ≦ 5, and more specifically, TTL and F may further satisfy TTL/F ≦ 4. The condition TTL/F is less than or equal to 5, and the miniaturization characteristic of the lens can be realized.

In an exemplary embodiment, the maximum field angle FOVm of the optical lens, the entire set of focal length values F of the optical lens, and the image height Ym corresponding to the maximum field angle of the optical lens may satisfy (FOVm × F)/Ym ≧ 65, and more specifically, FOVm, F, and Ym may further satisfy (FOVm × F)/Ym ≧ 72. The lens satisfies the conditional expression (FOVm multiplied by F)/Ym is larger than or equal to 65, and the lens has the characteristics of long focus and large field angle.

In an exemplary embodiment, the first lens may be arranged as 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. Further, providing the first lens as an aspherical mirror contributes to the effect of a long focus and a large angle of view.

The optical lens according to the above-described embodiment of the present application has many advantages. First, the lens achieves a multifunctional composite in performance: the lens has a small central angle (a small field angle range is arranged at a position close to the center), namely the long-focus function characteristic of the traditional front-view lens is realized; the whole lens has the characteristics of more than 80 degrees of full angle, namely the characteristic of large field angle of the short-focus lens, and has the functions of the traditional wide-angle lens; the single lens is compatible with the functions of the long-focus lens and the short-focus lens, can replace a plurality of lenses with traditional single functions in a driving system, and achieves the effect of expanding the visual range of the front-view lens, thereby greatly reducing the overall cost of the driving system and effectively increasing the actual usability of the lenses. Secondly, the lens has optical characteristics of large aperture, high resolution, large field angle (FOVm is more than 80 degrees), long overall focal length and large angular resolution in the central area. Finally, the lens is low in manufacturing cost and can better meet the requirements of the vehicle-mounted lens.

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 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 L1 is an aspherical lens. Further, the first lens L1 has a shape close to a concentric circle.

The second lens L2 is a biconvex lens with positive power, and has a convex object-side surface S3 and a convex image-side surface S4. The third lens L3 is a meniscus lens with negative power, with the object side S6 being convex and the image side S7 being concave. The fourth lens element L4 is a biconvex lens with positive power, and has a convex object-side surface S7 and a convex image-side surface S8. Wherein, the third lens L3 and the fourth lens L4 are cemented to form a cemented lens.

The fifth lens L5 is a biconvex lens with positive optical power, and has a convex object-side surface S9 and a convex image-side surface S10.

Optionally, the optical lens may further include a filter L6 and/or a protective lens L6' having an object side S11 and an image side S12. 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 S12 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 second lens L2 and the third lens L3 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	4.1000	2.5219	1.59	61.10
2	1.8226	5.2608
					3	13.1721	2.4549	1.90	31.32
4	-13.1721	0.9808
					STO	All-round	0.0500
6	111.0279	0.6000	1.85	23.79
					7	5.0992	2.6193	1.52	64.21
8	-10.7315	0.1000
					9	7.3937	4.0688	1.50	81.59
10	-23.6578	0.5000
					11	All-round	0.5500	1.52	64.21
12	All-round	4.0456
					IMA	All-round

The embodiment adopts five lenses as an example, and by reasonably distributing the focal power and the surface type of each lens, the central thickness of each lens and the air space among the lenses, the lens can have the effects of longer overall focal length, large aperture, large field angle and high pixel, and simultaneously realize the characteristic of large-angle resolution in the central area. 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 and S2 in example 1.

TABLE 2

Flour mark

K

A

B

C

D

E

1

-0.3808

-2.4554E-03

-1.8102E-04

-4.3907E-07

3.7881E-07

-1.1003E-08

2

-0.8961

-2.0190E-03

-1.4497E-03

1.4722E-04

-6.5053E-06

1.0152E-07

Table 3 below gives the radius of curvature R1 of the object-side surface S1 of the first lens L1, the radius of curvature R2 of the image-side surface S2 of the first lens L1, the distance d1 of the first lens L1 on the optical axis, the focal length value F1 of the first lens L1, the entire group focal length value F of the optical lens, the total optical 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 imaging surface S13), the maximum field angle FOVm of the optical lens, and the image height Ym corresponding to the maximum field angle of the optical lens in the optical lens of embodiment 1.

TABLE 3

Parameter(s)	R1(mm)	R2(mm)	d1(mm)	F1(mm)
					Numerical value	4.10	1.82	2.52	-9.45
Parameter(s)	F(mm)	TTL(mm)	FOVm(°)	Ym(mm)
					Numerical value	6.04	23.75	80	6.59

In the present embodiment, R1/(R2+ d1) is 0.944 among the radius of curvature R1 of the object-side surface S1 of the first lens L1, the radius of curvature R2 of the image-side surface S2 of the first lens L1, and the distance d1 on the optical axis of the first lens L1 in the optical lens; an | F1/F | 1.565 is satisfied between the focal length value F1 of the first lens L1 and the entire group focal length value F of the optical lens; 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 3.935; and 73.303 is satisfied among the maximum angle of view FOvm of the optical lens, the entire group of focal length values F of the optical lens, and the image height Ym corresponding to the maximum angle of view 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.

Optionally, the optical lens may further include a filter L6 and a protection lens L7, the filter L6 having an object side S11 and an image side S12, and the protection lens L7 having an object side S13 and an image side S14. Filter L6 can be used to correct for color deviations. The protective lens L7 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 S14 in sequence and is finally imaged on the imaging plane IMA.

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). Table 5 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 and S2 in example 2. Table 6 below gives the radius of curvature R1 of the object-side surface S1 of the first lens L1, the radius of curvature R2 of the image-side surface S2 of the first lens L1, the distance d1 of the first lens L1 on the optical axis, the focal length value F1 of the first lens L1, the entire group focal length value F of the optical lens, the total optical 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 imaging surface S15), the maximum field angle FOVm of the optical lens, and the image height Ym corresponding to the maximum field angle of the optical lens in the optical lens of embodiment 2.

TABLE 4

Flour mark	Radius of curvature R	Thickness T	Refractive index Nd	Abbe number Vd
					1	4.2814	2.7208	1.81	41.00
2	1.9479	4.5189
					3	15.2327	2.6790	1.90	31.32
4	-11.8702	1.1366
					STO	All-round	0.5109
6	17.0039	0.6000	1.92	18.90
					7	5.5928	2.7685	1.52	64.21
8	-12.8727	0.1000
					9	7.2290	5.2647	1.49	70.42
10	-34.0891	0.4922
					11	All-round	0.5500	1.52	64.21
12	All-round	1.5733
					13	All-round	0.5000	1.52	64.21
14	All-round	0.3804
					IMA	All-round

TABLE 5

Flour mark

K

A

B

C

D

E

1

-0.4130

-1.5317E-03

-7.7300E-05

-7.1036E-06

4.4913E-07

-8.2105E-09

2

-0.7609

-3.6397E-03

-1.2401E-03

6.2013E-05

4.6343E-07

-1.5547E-07

TABLE 6

Parameter(s)	R1(mm)	R2(mm)	d1(mm)	F1(mm)
					Numerical value	4.28	1.95	2.72	-9.21
Parameter(s)	F(mm)	TTL(mm)	FOVm(°)	Ym(mm)
					Numerical value	6.26	23.80	100	7.49

In the present embodiment, R1/(R2+ d1) is 0.917 between the radius of curvature R1 of the object-side surface S1 of the first lens L1, the radius of curvature R2 of the image-side surface S2 of the first lens L1, and the distance d1 on the optical axis of the first lens L1 in the optical lens; an | F1/F | of 1.471 is satisfied between the focal length value F1 of the first lens L1 and the whole group focal length value F of the optical lens; 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 3.803; and 83.482 is satisfied among the maximum angle of view FOvm of the optical lens, the entire group of focal length values F of the optical lens, and the image height Ym corresponding to the maximum angle of view of the optical lens.

In summary, examples 1 to 2 each satisfy the relationship shown in table 7 below.

TABLE 7

Conditions/examples	1	2
			R1/(R2+d1)	0.944	0.917
I F1/F I	1.565	1.471
			TTL/F	3.935	3.803
(FOVm×F)/Ym	73.303	83.482

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, wherein the number of the lenses with focal power is five,

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

the first lens and the third lens each have a negative optical power;

the second lens, the fourth lens and the fifth lens each have positive optical power,

the first lens and the third lens are both convex in object side surface and concave in image side surface;

the object side surface and the image side surface of the second lens, the fourth lens and the fifth lens are convex surfaces; and

the third lens is cemented with the fourth lens,

wherein an | F1/F | > or equal to 1.4 is satisfied between the focal length value F1 of the first lens and the whole group focal length value F of the optical lens.

2. An optical lens according to claim 1, characterized in that the first lens is an aspherical mirror.

3. An optical lens according to claim 1, wherein a radius of curvature R1 of an object side surface of the first lens, a radius of curvature R2 of an image side surface of the first lens, and a distance d1 of the first lens on the optical axis satisfy: R1/(R2+ d1) is more than or equal to 0.6 and less than or equal to 1.4.

4. An optical lens barrel according to any one of claims 1 to 3, wherein a distance TTL between a center of an object side surface of the first lens and an imaging surface of the optical lens on the optical axis and a full group focal length value F of the optical lens satisfy: TTL/F is less than or equal to 5.

5. The optical lens according to any one of claims 1 to 3, wherein (FOVm x F)/(Ym x 180 °) of ≧ 0.361 are satisfied among a maximum field angle FOvm of the optical lens, a whole group focal length value F of the optical lens, and an image height Ym corresponding to the maximum field angle of the optical lens.

6. An optical lens according to claim 1, characterized in that the optical lens further comprises a diaphragm disposed between the second lens and the third lens.

7. 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, wherein the number of the lenses with focal power is five,

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

the first lens and the third lens each have a negative optical power, an

the object side surface of the third lens is a convex surface;

the image side surfaces of the fourth lens and the fifth lens are convex surfaces;

wherein a radius of curvature R1 of an object-side surface of the first lens, a radius of curvature R2 of an image-side surface of the first lens, and a distance d1 of the first lens on the optical axis satisfy: R1/(R2+ d1) is more than or equal to 0.6 and less than or equal to 1.4; and

the maximum field angle FOVm of the optical lens, the whole group of focal length values F of the optical lens and the image height Ym corresponding to the maximum field angle of the optical lens meet the condition that (FOVm multiplied by F)/(Ym multiplied by 180 DEG) is not less than 0.361.

8. An optical lens barrel according to claim 7, wherein the first lens element has a convex object-side surface and a concave image-side surface; and

the image side surface of the third lens is a concave surface.

9. An optical lens barrel according to claim 7, wherein the object-side surface and the image-side surface of the second lens are convex; and

the object side surfaces of the fourth lens and the fifth lens are convex surfaces.

10. An optical lens according to any one of claims 7 to 9, characterized in that the third lens is cemented with the fourth lens.

11. An optical lens according to any one of claims 7 to 9, characterized in that the first lens is an aspherical mirror.

12. The optical lens according to claim 11, wherein | F1/F | > 1.2 is satisfied between the focal length value F1 of the first lens and the entire set of focal length values F of the optical lens.

13. An optical lens barrel according to any one of claims 7 to 9, wherein a distance TTL between a center of an object side surface of the first lens and an imaging surface of the optical lens on the optical axis and a full group focal length value F of the optical lens satisfy: TTL/F is less than or equal to 5.

14. An optical lens according to claim 7, characterized in that the optical lens further comprises a diaphragm disposed between the second lens and the third lens.

15. The optical lens assembly, in order from an object side to an image side along an optical axis, comprises: a first lens, a second lens, a third lens, a fourth lens and a fifth lens, wherein the number of the lenses with focal power is five,

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

the first lens and the third lens each have a negative optical power;

the second lens, the fourth lens and the fifth lens each have positive optical power;

the third lens is glued with the fourth lens;

the object side surface of the third lens is a convex surface;

the image side surfaces of the fourth lens and the fifth lens are convex surfaces; and

16. An optical lens barrel according to claim 15, wherein the first lens element has a convex object-side surface and a concave image-side surface; and

the image side surface of the third lens is a concave surface.

17. An optical lens barrel according to claim 15, wherein the object-side surface and the image-side surface of the second lens are convex; and

18. An optical lens according to claim 15, characterized in that the first lens is an aspherical mirror.

19. The optical lens according to claim 18, wherein | F1/F | > 1.2 is satisfied between the focal length value F1 of the first lens and the entire set of focal length values F of the optical lens.

20. An optical lens as claimed in claim 19, characterized in that a radius of curvature R1 of the object-side surface of the first lens, a radius of curvature R2 of the image-side surface of the first lens and a distance d1 of the first lens on the optical axis satisfy: R1/(R2+ d1) is more than or equal to 0.6 and less than or equal to 1.4.

21. An optical lens barrel according to any one of claims 15 to 20, wherein a distance TTL between a center of an object side surface of the first lens and an imaging surface of the optical lens on the optical axis and a full group focal length value F of the optical lens satisfy: TTL/F is less than or equal to 5.

22. An optical lens according to claim 15, characterized in that the optical lens further comprises a diaphragm disposed between the second lens and the third lens.