Patent application title:

Camera optical lens

Publication number:

US20190204547A1

Publication date:
Application number:

15/871,236

Filed date:

2018-01-15

βœ… Patent granted

Patent number:

US 10,353,181 B1

Grant date:

2019-07-16

PCT filing:

-

PCT publication:

-

Examiner:

Joseph P Martinez

Agent:

Na Xu | IPro, PLLC

Adjusted expiration:

2038-01-15

Abstract:

The present disclosure discloses a camera optical lens. The camera optical lens including, in an order from an object side to an image side, a first lens, a second lens having a positive refractive power, a third lens having a negative refractive power, a fourth lens, a fifth lens, and a sixth lens. The first lens is made of glass material, the second lens is made of plastic material, the third lens is made of plastic material, the fourth lens is made of plastic material, the fifth lens is made of plastic material, and the sixth lens is made of glass material. The camera optical lens further satisfies specific conditions.

Inventors:

Assignee:

Applicant:

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Classification:

G02B13/0045 »  CPC main

Optical objectives specially designed for the purposes specified below; Miniaturised objectives for electronic devices, e.g. portable telephones, webcams, PDAs, small digital cameras characterised by the lens design having at least one aspherical surface having five or more lenses

G02B1/041 »  CPC further

Optical elements characterised by the material of which they are made; Optical coatings for optical elements made of organic materials, e.g. plastics Lenses

G02B13/00 IPC

Optical objectives specially designed for the purposes specified below

G02B1/04 IPC

Optical elements characterised by the material of which they are made; Optical coatings for optical elements made of organic materials, e.g. plastics

G02B9/62 »  CPC further

Optical objectives characterised both by the number of the components and their arrangements according to their sign, i.e. + or - having six components only

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the priority benefit of Chinese Patent Applications Ser. No. 201711482789.9 and Ser. No. 201711482784.6 filed on Dec. 29, 2017, the entire content of which is incorporated herein by reference.

FIELD OF THE PRESENT DISCLOSURE

The present disclosure relates to optical lens, in particular to a camera optical lens suitable for handheld devices such as smart phones and digital cameras and imaging devices.

DESCRIPTION OF RELATED ART

With the emergence of smart phones in recent years, the demand for miniature camera lens is increasing day by day, but the photosensitive devices of general camera lens are no other than Charge Coupled Device (CCD) or Complementary metal-Oxide Semiconductor Sensor (CMOS sensor), and as the progress of the semiconductor manufacturing technology makes the pixel size of the photosensitive devices shrink, coupled with the current development trend of electronic products being that their functions should be better and their shape should be thin and small, miniature camera lens with good imaging quality therefor has become a mainstream in the market. In order to obtain better imaging quality, the lens that is traditionally equipped in mobile phone cameras adopts a three-piece or four-piece lens structure. And, with the development of technology and the increase of the diverse demands of users, and under this circumstances that the pixel area of photosensitive devices is shrinking steadily and the requirement of the system for the imaging quality is improving constantly, the five-piece, six-piece and seven-piece lens structure gradually appear in lens design. There is an urgent need for ultra-thin wide-angle camera lenses which have good optical characteristics and the chromatic aberration of which is fully corrected.

BRIEF DESCRIPTION OF THE DRAWINGS

Many aspects of the exemplary embodiments can be better understood with reference to the following drawings. The components in the drawing are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present disclosure.

FIG. 1 is a schematic diagram of a camera optical lens in accordance with a first embodiment of the present invention;

FIG. 2 shows the longitudinal aberration of the camera optical lens shown in FIG. 1;

FIG. 3 shows the lateral color of the camera optical lens shown in FIG. 1;

FIG. 4 presents a schematic diagram of the field curvature and distortion of the camera optical lens shown in FIG. 1;

FIG. 5 is a schematic diagram of a camera optical lens in accordance with a second embodiment of the present invention;

FIG. 6 presents the longitudinal aberration of the camera optical lens shown in FIG. 5;

FIG. 7 presents the lateral color of the camera optical lens shown in FIG. 5;

FIG. 8 presents the field curvature and distortion of the camera optical lens shown in FIG. 5;

FIG. 9 is a schematic diagram of a camera optical lens in accordance with a third embodiment of the present invention;

FIG. 10 presents the longitudinal aberration of the camera optical lens shown in FIG. 9;

FIG. 11 presents the lateral color of the camera optical lens shown in FIG. 9;

FIG. 12 presents the field curvature and distortion of the camera optical lens shown in FIG. 9.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

The present disclosure will hereinafter be described in detail with reference to several exemplary embodiments. To make the technical problems to be solved, technical solutions and beneficial effects of the present disclosure more apparent, the present disclosure is described in further detail together with the figure and the embodiments. It should be understood the specific embodiments described hereby is only to explain the disclosure, not intended to limit the disclosure.

Embodiment 1

As referring to FIG. 1, the present invention provides a camera optical lens 10. FIG. 1 shows the camera optical lens 10 of embodiment 1 of the present invention, the camera optical lens 10 comprises 6 lenses. Specifically, from the object side to the image side, the camera optical lens 10 comprises in sequence: an aperture S1, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, and a sixth lens L6. Optical element like optical filter GF can be arranged between the sixth lens L6 and the image surface Si. The first lens L1 is made of glass material, the second lens L2 is made of plastic material, the third lens L3 is made of plastic material, the fourth lens L4 is made of plastic material, the fifth lens L5 is made of plastic material, and the sixth lens L6 is made of glass material.

The second lens L2 has a positive refractive power, and the third lens L3 has a negative refractive power.

Here, the focal length of the whole camera optical lens 10 is defined as f, the focal length of the first lens is defined as f1. The camera optical lens 10 further satisfies the following condition: βˆ’3≀f1/fβ‰€βˆ’1.7. Condition βˆ’3≀f1/fβ‰€βˆ’1.7 fixes the negative refractive power of the first lens L1. If the upper limit of the set value is exceeded, although it benefits the ultra-thin development of lenses, but the negative refractive power of the first lens L1 will be too strong, problem like aberration is difficult to be corrected, and it is also unfavorable for wide-angle development of lens. On the contrary, if the lower limit of the set value is exceeded, the negative refractive power of the first lens L1 becomes too weak, it is then difficult to develop ultra-thin lenses. Preferably, the following condition shall be satisfied, βˆ’2.997≀f1/fβ‰€βˆ’1.73.

The refractive power of the first lens L1 is defined as n1. Here the following condition should satisfied: 1.7≀n1≀2.2. This condition fixes the refractive power of the first lens L1, and refractive power within this range benefits the ultra-thin development of lenses, and it also benefits the correction of aberration. Preferably, the following condition shall be satisfied, 1.709≀n1≀2.06.

The refractive power of the sixth lens L6 is defined as n6. Here the following condition should satisfied: 1.7≀n6≀2.2. This condition fixes the refractive power of the sixth lens L6, and refractive power within this range benefits the ultra-thin development of lenses, and it also benefits the correction of aberration. Preferably, the following condition shall be satisfied, 1.707≀n6≀2.04.

In this embodiment, the first lens L1 has a negative refractive power with a convex object side surface relative to the proximal axis and a concave image side surface relative to the proximal axis.

The curvature radius of the object side surface of the first lens L1 is defined as R1, the curvature radius of the image side surface of the first lens L1 is defined as R2. The camera optical lens 10 further satisfies the following condition: 2.55≀(R1+R2)/(R1-R2)≀9.45, which fixes the shape of the first lens L1. When the value is beyond this range, with the development into the direction of ultra-thin and wide-angle lenses, problem like aberration of the off-axis picture angle is difficult to be corrected. Preferably, the condition 4.08≀(R1+R2)/(R1-R2)≀7.56 shall be satisfied.

The thickness on-axis of the first lens L1 is defined as d1. The following condition: 0.12≀d1≀0.37 should be satisfied. When the condition is satisfied, it is beneficial for realization of the ultra-thin lens. Preferably, the condition 0.19≀d1≀0.29 shall be satisfied.

In this embodiment, the second lens L2 has a convex object side surface and a convex image side surface relative to the proximal axis.

The focal length of the whole camera optical lens 10 is f, the focal length of the second lens L2 is f2. The following condition should be satisfied: 0.31≀f2/f≀1.08. When the condition is satisfied, the positive refractive power of the second lens L2 is controlled within reasonable scope, the spherical aberration caused by the first lens L1 which has negative refractive power and the field curvature of the system then can be reasonably and effectively balanced. Preferably, the condition 0.5≀f2/f≀0.87 should be satisfied.

The curvature radius of the object side surface of the second lens L2 is defined as R3, the curvature radius of the image side surface of the second lens L2 is defined as R4. The following condition should be satisfied: βˆ’1.85≀(R3+R4)/(R3βˆ’R4)β‰€βˆ’0.41, which fixes the shape of the second lens L2 and can effectively correct aberration of the camera optical lens. Preferably, the following condition shall be satisfied, βˆ’1.16≀(R3+R4)/(R3βˆ’R4)β‰€βˆ’0.51.

The thickness on-axis of the second lens L2 is defined as d3. The following condition: 0.31≀d3≀0.94 should be satisfied. When the condition is satisfied, it is beneficial for realization of the ultra-thin lens. Preferably, the condition 0.49≀d3≀0.75 shall be satisfied.

In this embodiment, the third lens L3 has a concave image side surface relative to the proximal axis.

The focal length of the whole camera optical lens 10 is f, the focal length of the third lens L3 is f3. The following condition should be satisfied: βˆ’7.18≀f3/fβ‰€βˆ’1.05, by which the field curvature of the system then can be reasonably and effectively balanced. Preferably, the condition βˆ’4.49≀f3/fβ‰€βˆ’1.31 should be satisfied.

The curvature radius of the object side surface of the third lens L3 is defined as R5, the curvature radius of the image side surface of the third lens L3 is defined as R6. The following condition should be satisfied: βˆ’0.95≀(R5+R6)/(R5βˆ’R6)≀7.47, by which, with the development into the direction of ultra-thin and wide-angle lenses, problem like aberration of the off-axis picture angle is difficult to be corrected. Preferably, the following condition shall be satisfied, βˆ’0.59≀(R5+R6)/(R5βˆ’R6)≀5.98.

The thickness on-axis of the third lens L3 is defined as d5. The following condition: 0.12≀d5≀0.72 should be satisfied. When the condition is satisfied, it is beneficial for realization of the ultra-thin lens. Preferably, the condition 0.18≀d5≀0.58 shall be satisfied.

In this embodiment, the fourth lens L4 has a positive refractive power with a concave object side surface and a convex image side surface relative to the proximal axis.

The focal length of the whole camera optical lens 10 is f, the focal length of the fourth lens L4 is f4. The following condition should be satisfied: 0.61≀f4/f≀21.4, which can effectively reduce the sensitivity of lens group used in camera and further enhance the imaging quality. Preferably, the condition 0.98≀f4/f≀17.12 should be satisfied.

The curvature radius of the object side surface of the fourth lens L4 is defined as R7, the curvature radius of the image side surface of the fourth lens L4 is defined as R8. The following condition should be satisfied: βˆ’101.57≀(R7+R8)/(R7βˆ’R8)≀6.46, by which, with the development into the direction of ultra-thin and wide-angle lenses, problem like aberration of the off-axis picture angle is difficult to be corrected. Preferably, the following condition shall be satisfied, βˆ’63.48≀(R7+R8)/(R7βˆ’R8)≀5.17.

The thickness on-axis of the fourth lens L4 is defined as d7. The following condition: 0.18≀d7≀0.97 should be satisfied. When the condition is satisfied, it is beneficial for realization of the ultra-thin lens. Preferably, the condition 0.29≀d7≀0.77 shall be satisfied.

In this embodiment, the fifth lens L5 has a positive refractive power with a convex object side surface and a convex image side surface relative to the proximal axis.

The focal length of the whole camera optical lens 10 is f, the focal length of the fifth lens L5 is f5. The following condition should be satisfied: 0.33≀f5/f≀1.52, which can effectively smooth the light angles of the camera and reduce the tolerance sensitivity. Preferably, the condition 0.52≀f5/f≀1.22 should be satisfied.

The curvature radius of the object side surface of the fifth lens L5 is defined as R9, the curvature radius of the image side surface of the fifth lens L5 is defined as R10. The following condition should be satisfied: 0.05≀(R9+R10)/(R9βˆ’R10)≀0.96 by which, the shape of the fifth lens L5 is fixed, further, with the development into the direction of ultra-thin and wide-angle lenses, problem like aberration of the off-axis picture angle is difficult to be corrected. Preferably, the following condition shall be satisfied, 0.08≀(R9+R10)/(R9βˆ’R10)≀0.77.

The thickness on-axis of the fifth lens L5 is defined as d9. The following condition: 0.38≀d9≀1.42 should be satisfied. When the condition is satisfied, it is beneficial for realization of the ultra-thin lens. Preferably, the condition 0.6≀d9≀1.14 shall be satisfied.

In this embodiment, the sixth lens L6 has a negative refractive power with a concave object side surface and a concave image side surface relative to the proximal axis.

The focal length of the whole camera optical lens 10 is f, the focal length of the sixth lens L6 is f6. The following condition should be satisfied: βˆ’0.99≀f6/fβ‰€βˆ’0.27, which can effectively reduce the sensitivity of lens group used in camera and further enhance the imaging quality. Preferably, the condition βˆ’0.62≀f6/fβ‰€βˆ’0.34 should be satisfied.

The curvature radius of the object side surface of the sixth lens L6 is defined as R11, the curvature radius of the image side surface of the sixth lens L6 is defined as R12. The following condition should be satisfied: βˆ’1.01≀(R11+R12)/(R11βˆ’R12)≀0.08, by which, the shape of the sixth lens L6 is fixed, further, with the development into the direction of ultra-thin and wide-angle lenses, problem like aberration of the off-axis picture angle is difficult to be corrected. Preferably, the following condition shall be satisfied, βˆ’0.63≀(R11+R12)/(R11βˆ’R12)≀0.06.

The thickness on-axis of the sixth lens L6 is defined as d11. The following condition: 0.11≀d11≀0.38 should be satisfied. When the condition is satisfied, it is beneficial for realization of the ultra-thin lens. Preferably, the condition 0.18≀d11≀0.3 shall be satisfied.

The focal length of the whole camera optical lens 10 is f, the combined focal length of the first lens L1 and the second lens L2 is f12. The following condition should be satisfied: 0.49≀f12/f≀1.57, which can effectively avoid the aberration and field curvature of the camera optical lens, and can suppress the rear focal length for realizing the ultra-thin lens. Preferably, the condition 0.79≀f12/f≀1.26 should be satisfied.

In this embodiment, the total optical length TTL of the camera optical lens 10 is less than or equal to 5.72 mm, it is beneficial for the realization of ultra-thin lenses. Preferably, the total optical length TTL of the camera optical lens 10 is less than or equal to 5.46 mm.

In this embodiment, the aperture F number of the camera optical lens 10 is less than or equal to 2.16. A large aperture has better imaging performance. Preferably, the aperture F number of the camera optical lens 10 is less than or equal to 2.12.

With such design, the total optical length TTL of the whole camera optical lens 10 can be made as short as possible, thus the miniaturization characteristics can be maintained.

In the following, an example will be used to describe the camera optical lens 10 of the present invention. The symbols recorded in each example are as follows. The unit of distance, radius and center thickness is mm.

TTL: Optical length (the distance on-axis from the object side surface of the first lens L1 to the image surface).

Preferably, inflexion points and/or arrest points can also be arranged on the object side surface and/or image side surface of the lens, so that the demand for high quality imaging can be satisfied, the description below can be referred for specific implementable scheme.

The design information of the camera optical lens 10 in the first embodiment of the present invention is shown in the following, the unit of the focal length, distance, radius and center thickness is mm.

The design information of the camera optical lens 10 in the first embodiment of the present invention is shown in the tables 1 and 2.

TABLE 1
R d nd Ξ½d
S1 ∞ d0= βˆ’0.050
R1 2.678 d1= 0.240 nd1 1.7174 Ξ½1 29.50
R2 1.945 d2= 0.047
R3 1.772 d3= 0.620 nd2 1.5445 Ξ½2 55.99
R4 βˆ’8.598 d4= 0.654
R5 βˆ’5.391 d5= 0.483 nd3 1.6510 Ξ½3 21.51
R6 15.138 d6= 0.174
R7 βˆ’2.490 d7= 0.525 nd4 1.5352 Ξ½4 56.09
R8 βˆ’1.552 d8= 0.030
R9 4.000 d9= 0.770 nd5 1.5352 Ξ½5 56.09
R10 βˆ’3.287 d10= 0.529
R11 βˆ’1.818 d11= 0.250 nd6 1.7130 Ξ½6 53.94
R12 5.554 d12= 0.164
R13 ∞ d13= 0.210 ndg 1.5168 νg 64.17
R14 ∞ d14= 0.500

Where:

In which, the meaning of the various symbols is as follows.

S1: Aperture;

R: The curvature radius of the optical surface, the central curvature radius in case of lens;

R1: The curvature radius of the object side surface of the first lens L1;

R2: The curvature radius of the image side surface of the first lens L1;

R3: The curvature radius of the object side surface of the second lens L2;

R4: The curvature radius of the image side surface of the second lens L2;

R5: The curvature radius of the object side surface of the third lens L3;

R6: The curvature radius of the image side surface of the third lens L3;

R7: The curvature radius of the object side surface of the fourth lens L4;

R8: The curvature radius of the image side surface of the fourth lens L4;

R9: The curvature radius of the object side surface of the fifth lens L5;

R10: The curvature radius of the image side surface of the fifth lens L5;

R11: The curvature radius of the object side surface of the sixth lens L6;

R12: The curvature radius of the image side surface of the sixth lens L6;

R13: The curvature radius of the object side surface of the optical filter GF;

R14: The curvature radius of the image side surface of the optical filter GF;

d: The thickness on-axis of the lens and the distance on-axis between the lens;

d0: The distance on-axis from aperture S1 to the object side surface of the first lens L1;

d1: The thickness on-axis of the first lens L1;

d2: The distance on-axis from the image side surface of the first lens L1 to the object side surface of the second lens L2;

d3: The thickness on-axis of the second lens L2;

d4: The distance on-axis from the image side surface of the second lens L2 to the object side surface of the third lens L3;

d5: The thickness on-axis of the third lens L3;

d6: The distance on-axis from the image side surface of the third lens L3 to the object side surface of the fourth lens L4;

d7: The thickness on-axis of the fourth lens L4;

d8: The distance on-axis from the image side surface of the fourth lens L4 to the object side surface of the fifth lens L5;

d9: The thickness on-axis of the fifth lens L5;

d10: The distance on-axis from the image side surface of the fifth lens L5 to the object side surface of the sixth lens L6;

d11: The thickness on-axis of the sixth lens L6;

d12: The distance on-axis from the image side surface of the sixth lens L6 to the object side surface of the optical filter GF;

d13: The thickness on-axis of the optical filter GF;

d14: The distance on-axis from the image side surface to the image surface of the optical filter GF;

nd: The refractive power of the d line;

nd1: The refractive power of the d line of the first lens L1;

nd2: The refractive power of the d line of the second lens L2;

nd3: The refractive power of the d line of the third lens L3;

nd4: The refractive power of the d line of the fourth lens L4;

nd5: The refractive power of the d line of the fifth lens L5;

nd6: The refractive power of the d line of the sixth lens L6;

ndg: The refractive power of the d line of the optical filter GF;

vd: The abbe number;

v1: The abbe number of the first lens L1;

v2: The abbe number of the second lens L2;

v3: The abbe number of the third lens L3;

v4: The abbe number of the fourth lens L4;

v5: The abbe number of the fifth lens L5;

v6: The abbe number of the sixth lens L6;

vg: The abbe number of the optical filter GF.

Table 2 shows the aspherical surface data of the camera optical lens 10 in the embodiment 1 of the present invention.

TABLE 2
Conic Index Aspherical Surface Index
k A4 A6 A8 A10 A12 A14 A16
R1 βˆ’9.8698E+00 βˆ’1.5486Eβˆ’03 βˆ’2.9994Eβˆ’02  βˆ’3.4203Eβˆ’02   4.3151Eβˆ’02  2.9088Eβˆ’02 βˆ’8.8856Eβˆ’02 4.6556Eβˆ’02
R2 βˆ’4.9188E+00  8.9236Eβˆ’03 βˆ’2.7687Eβˆ’02  βˆ’7.1484Eβˆ’02   1.0373Eβˆ’01 βˆ’3.7502Eβˆ’02 βˆ’2.2512Eβˆ’02 1.7338Eβˆ’02
R3 βˆ’2.7524E+00  5.5065Eβˆ’02 βˆ’4.4873Eβˆ’05  βˆ’3.1165Eβˆ’02   4.0508Eβˆ’02 βˆ’6.6219Eβˆ’03 βˆ’8.2856Eβˆ’03 2.0847Eβˆ’03
R4 βˆ’3.4727E+00 βˆ’3.0432Eβˆ’02 4.1727Eβˆ’04 2.8682Eβˆ’02 βˆ’3.6500Eβˆ’02  3.2442Eβˆ’02 βˆ’1.8928Eβˆ’02 3.0733Eβˆ’03
R5  0.0000E+00 βˆ’1.8180Eβˆ’01 5.4788Eβˆ’03 4.2460Eβˆ’02 βˆ’7.8282Eβˆ’02  9.8914Eβˆ’03  6.8416Eβˆ’02 βˆ’4.1643Eβˆ’02 
R6  0.0000E+00 βˆ’1.3961Eβˆ’01 4.7302Eβˆ’02 βˆ’1.2792Eβˆ’02   3.9915Eβˆ’03  2.7470Eβˆ’03 βˆ’1.3972Eβˆ’03 3.2924Eβˆ’04
R7  1.8318E+00  4.9528Eβˆ’02 βˆ’1.4800Eβˆ’02  1.8125Eβˆ’02  1.3983Eβˆ’03 βˆ’1.7960Eβˆ’03 βˆ’1.9587Eβˆ’04 3.9285Eβˆ’04
R8 βˆ’2.7486E+00 βˆ’4.5471Eβˆ’02 1.0553Eβˆ’02 5.6863Eβˆ’03 βˆ’1.4364Eβˆ’03 βˆ’1.4541Eβˆ’04  2.9786Eβˆ’04 βˆ’3.0112Eβˆ’05 
R9  3.5031Eβˆ’01 βˆ’2.9323Eβˆ’02 3.0495Eβˆ’03 6.4844Eβˆ’04 βˆ’3.3702Eβˆ’04 βˆ’4.1834Eβˆ’05  8.6652Eβˆ’06 βˆ’3.3617Eβˆ’07 
R10  0.0000E+00  1.3047Eβˆ’02 3.6668Eβˆ’03 1.9437Eβˆ’04 βˆ’1.3873Eβˆ’04 βˆ’4.3145Eβˆ’05 βˆ’1.4472Eβˆ’06 1.7401Eβˆ’06
R11 βˆ’4.1517E+00 βˆ’3.5595Eβˆ’02 4.9524Eβˆ’03 6.3541Eβˆ’04 βˆ’7.2256Eβˆ’05 βˆ’1.0687Eβˆ’05 βˆ’1.0791Eβˆ’06 5.4310Eβˆ’07
R12 βˆ’2.6038E+00 βˆ’3.0856Eβˆ’02 3.2850Eβˆ’03 βˆ’5.9104Eβˆ’05  βˆ’1.6169Eβˆ’05 βˆ’1.9702Eβˆ’06  6.4743Eβˆ’08 2.3180Eβˆ’08

Among them, K is a conic index, A4, A6, A8, A10, A12, A14, A16 are aspheric surface indexes.

IH: Image height


y=(x2/R)/[1+{1βˆ’(k+1)(x2/R2)}1/2]+A4x4+A6x6+A8x8+A10x10°±A12x12+A14x14+A16x16  (1)

For convenience, the aspheric surface of each lens surface uses the aspheric surfaces shown in the above condition (1). However, the present invention is not limited to the aspherical polynomials form shown in the condition (1).

Table 3 and table 4 show the inflexion points and the arrest point design data of the camera optical lens 10 lens in embodiment 1 of the present invention. In which, P1R1 and P1R2 represent respectively the object side surface and image side surface of the first lens L1, P2R1 and P2R2 represent respectively the object side surface and image side surface of the second lens L2, P3R1 and P3R2 represent respectively the object side surface and image side surface of the third lens L3, P4R1 and P4R2 represent respectively the object side surface and image side surface of the fourth lens L4, P5R1 and P5R2 represent respectively the object side surface and image side surface of the fifth lens L5, P6R1 and P6R2 represent respectively the object side surface and image side surface of the sixth lens L6. The data in the column named β€œinflexion point position” are the vertical distances from the inflexion points arranged on each lens surface to the optic axis of the camera optical lens 10. The data in the column named β€œarrest point position” are the vertical distances from the arrest points arranged on each lens surface to the optic axis of the camera optical lens 10.

TABLE 3
Inflexion
Inflexion point number Inflexion point position 1 point position 2
P1R1 1 0.655
P1R2 1 0.725
P2R1 0
P2R2 0
P3R1 0
P3R2 2 0.205 1.095
P4R1 1 0.955
P4R2 1 1.125
P5R1 1 1.085
P5R2 2 1.165 1.545
P6R1 1 1.605
P6R2 1 0.745

TABLE 4
Arrest
Arrest point number Arrest point position 1 point position 2
P1R1 0
P1R2 0
P2R1 0
P2R2 0
P3R1 0
P3R2 1 0.355
P4R1 1 1.345
P4R2 0
P5R1 1 1.635
P5R2 0
P6R1 0
P6R2 1 1.395

FIG. 2 and FIG. 3 show the longitudinal aberration and lateral color schematic diagrams after light with a wavelength of 470 nm, 555 nm and 650 nm passes the camera optical lens 10 in the first embodiment. FIG. 4 shows the field curvature and distortion schematic diagrams after light with a wavelength of 555 nm passes the camera optical lens 10 in the first embodiment, the field curvature S in FIG. 4 is a field curvature in the sagittal direction, T is a field curvature in the meridian direction.

Table 13 shows the various values of the embodiments 1, 2, 3, and the values corresponding with the parameters which are already specified in the conditions.

As shown in Table 13, the first embodiment satisfies the various conditions.

In this embodiment, the pupil entering diameter of the camera optical lens is 1.812 mm, the full vision field image height is 2.994 mm, the vision field angle in the diagonal direction is 76.34Β°, it has wide-angle and is ultra-thin, its on-axis and off-axis chromatic aberrations are fully corrected, and it has excellent optical characteristics.

Embodiment 2

Embodiment 2 is basically the same as embodiment 1, the meaning of its symbols is the same as that of embodiment 1, in the following, only the differences are described.

Table 5 and table 6 show the design data of the camera optical lens 20 in embodiment 2 of the present invention.

TABLE 5
R d nd Ξ½d
S1 ∞ d0= βˆ’0.050
R1 2.784 d1= 0.240 nd1 1.8052 Ξ½1 25.46
R2 1.872 d2= 0.083
R3 1.708 d3= 0.626 nd2 1.5445 Ξ½2 55.99
R4 βˆ’7.119 d4= 0.511
R5 5.876 d5= 0.230 nd3 1.6510 Ξ½3 21.51
R6 3.245 d6= 0.498
R7 βˆ’2.119 d7= 0.645 nd4 1.5352 Ξ½4 56.09
R8 βˆ’1.267 d8= 0.035
R9 11.263 d9= 0.751 nd5 1.5352 Ξ½5 56.09
R10 βˆ’2.484 d10= 0.389
R11 βˆ’2.676 d11= 0.240 nd6 1.7725 Ξ½6 49.50
R12 2.419 d12= 0.242
R13 ∞ d13= 0.210 ndg 1.5168 νg 64.17
R14 ∞ d14= 0.500

Table 6 shows the aspherical surface data of each lens of the camera optical lens 20 in embodiment 2 of the present invention.

TABLE 6
Conic Index Ashperical Surface Index
k A4 A6 A8 A10 A12 A14 A16
R1 βˆ’1.8854E+01 βˆ’9.8953Eβˆ’03 βˆ’4.5272Eβˆ’02  βˆ’4.0309Eβˆ’02  5.9657Eβˆ’02 2.4232Eβˆ’02 βˆ’8.9517Eβˆ’02 4.5251Eβˆ’02
R2 βˆ’9.4784E+00 βˆ’2.7326Eβˆ’03 βˆ’3.0608Eβˆ’02  βˆ’7.7578Eβˆ’02  9.5527Eβˆ’02 βˆ’2.3091Eβˆ’02  βˆ’3.5848Eβˆ’02 2.2228Eβˆ’02
R3 βˆ’6.2631E+00  8.9651Eβˆ’02 1.6847Eβˆ’02 βˆ’4.9919Eβˆ’02  4.7746Eβˆ’02 βˆ’3.6561Eβˆ’03  βˆ’1.1830Eβˆ’02 3.8317Eβˆ’03
R4  0.0000E+00 βˆ’3.9533Eβˆ’02 4.5407Eβˆ’02  1.3414Eβˆ’02 βˆ’1.7404Eβˆ’02 2.8766Eβˆ’02 βˆ’2.4420Eβˆ’02 3.8953Eβˆ’03
R5  0.0000E+00 βˆ’2.8060Eβˆ’01 1.4223Eβˆ’02  6.2107Eβˆ’02 βˆ’6.0593Eβˆ’02 5.7732Eβˆ’03  5.7552Eβˆ’02 βˆ’4.1778Eβˆ’02 
R6  0.0000E+00 βˆ’2.2908Eβˆ’01 5.3218Eβˆ’02 βˆ’3.6985Eβˆ’03  5.3853Eβˆ’03 2.5471Eβˆ’03 βˆ’5.1965Eβˆ’04 2.7769Eβˆ’04
R7  1.6542E+00  4.5729Eβˆ’02 βˆ’3.1171Eβˆ’02  βˆ’7.5957Eβˆ’03 βˆ’7.9603Eβˆ’03 1.0636Eβˆ’03  4.8293Eβˆ’03 2.6509Eβˆ’03
R8 βˆ’2.3784E+00 βˆ’6.4976Eβˆ’02 9.1340Eβˆ’04 βˆ’1.4212Eβˆ’03 βˆ’4.4904Eβˆ’03 βˆ’4.3892Eβˆ’04   4.6265Eβˆ’04 3.1612Eβˆ’04
R9  0.0000E+00 βˆ’4.0861Eβˆ’02 1.1557Eβˆ’02 βˆ’1.7773Eβˆ’03 βˆ’9.7843Eβˆ’04 7.6569Eβˆ’05  7.9874Eβˆ’05 βˆ’1.5202Eβˆ’05 
R10  0.0000E+00  1.5127Eβˆ’02 βˆ’1.1891Eβˆ’03  βˆ’2.5835Eβˆ’04 βˆ’1.8658Eβˆ’04 βˆ’1.7946Eβˆ’05   9.5479Eβˆ’06 5.9978Eβˆ’06
R11 βˆ’7.2924E+00 βˆ’4.8089Eβˆ’02 3.2088Eβˆ’03  7.8928Eβˆ’04 βˆ’3.5423Eβˆ’05 βˆ’8.9038Eβˆ’06  βˆ’1.6798Eβˆ’06 1.0489Eβˆ’06
R12 βˆ’1.1978E+01 βˆ’3.6125Eβˆ’02 5.5494Eβˆ’03 βˆ’3.7752Eβˆ’04 βˆ’2.6010Eβˆ’05 9.3413Eβˆ’07  4.7708Eβˆ’07 βˆ’3.0097Eβˆ’08 

Table 7 and table 8 show the inflexion points and the arrest point design data of the camera optical lens 20 lens in embodiment 2 of the present invention.

TABLE 7
Inflexion
Inflexion point number Inflexion point position 1 point position 2
P1R1 1 0.545
P1R2 1 0.605
P2R1 0
P2R2 1 0.705
P3R1 1 0.235
P3R2 2 0.355 1.035
P4R1 1 1.125
P4R2 1 1.345
P5R1 1 0.465
P5R2 1 1.655
P6R1 1 1.725
P6R2 1 0.675

TABLE 8
Arrest
Arrest point number Arrest point position 1 point position 2
P1R1 0
P1R2 0
P2R1 0
P2R2 0
P3R1 1 0.395
P3R2 1 0.635
P4R1 0
P4R2 0
P5R1 1 0.845
P5R2 0
P6R1 0
P6R2 1 1.435

FIG. 6 and FIG. 7 show the longitudinal aberration and lateral color schematic diagrams after light with a wavelength of 470 nm, 555 nm and 650 nm passes the camera optical lens 20 in the second embodiment. FIG. 8 shows the field curvature and distortion schematic diagrams after light with a wavelength of 555 nm passes the camera optical lens 20 in the second embodiment.

As shown in Table 13, the second embodiment satisfies the various conditions.

In this embodiment, the pupil entering diameter of the camera optical lens is 1.81 mm, the full vision field image height is 2.994 mm, the vision field angle in the diagonal direction is 76.46Β°, it has wide-angle and is ultra-thin, its on-axis and off-axis chromatic aberrations are fully corrected, and it has excellent optical characteristics.

Embodiment 3

Embodiment 3 is basically the same as embodiment 1, the meaning of its symbols is the same as that of embodiment 1, in the following, only the differences are described.

Table 9 and table 10 show the design data of the camera optical lens 30 in embodiment 3 of the present invention.

TABLE 9
R d nd Ξ½d
S1 ∞ d0= 0.000
R1 2.360 d1= 0.245 nd1 2.0018 Ξ½1 19.32
R2 1.655 d2= 0.055
R3 1.341 d3= 0.615 nd2 1.5445 Ξ½2 55.99
R4 βˆ’35.135 d4= 0.477
R5 4.185 d5= 0.234 nd3 1.6510 Ξ½3 21.51
R6 2.786 d6= 0.460
R7 βˆ’1.648 d7= 0.361 nd4 1.6613 Ξ½4 20.37
R8 βˆ’1.714 d8= 0.031
R9 2.920 d9= 0.947 nd5 1.5352 Ξ½5 56.09
R10 βˆ’2.145 d10= 0.389
R11 βˆ’2.124 d11= 0.230 nd6 1.8820 Ξ½6 37.22
R12 4.144 d12= 0.147
R13 ∞ d13= 0.210 ndg 1.5168 νg 64.17
R14 ∞ d14= 0.500

Table 10 shows the aspherical surface data of each lens of the camera optical lens 30 in embodiment 3 of the present invention.

TABLE 10
Conic Index Aspherical Surface Index
k A4 A6 A8 A10 A12 A14 A16
R1 βˆ’2.1162E+01  6.0258Eβˆ’02 βˆ’9.1849Eβˆ’02 βˆ’4.0082Eβˆ’02  1.1546Eβˆ’01 βˆ’1.6047Eβˆ’02  βˆ’1.2909Eβˆ’01 8.3334Eβˆ’02
R2 βˆ’1.5809E+01  4.0341Eβˆ’02 βˆ’1.4537Eβˆ’02 βˆ’1.5065Eβˆ’01  1.2634Eβˆ’01 5.7583Eβˆ’02 βˆ’1.5584Eβˆ’01 7.1855Eβˆ’02
R3 βˆ’1.0422E+01  1.3648Eβˆ’01  1.1611Eβˆ’02 βˆ’7.8591Eβˆ’02  6.0389Eβˆ’02 2.1858Eβˆ’02 βˆ’2.9636Eβˆ’02 2.9393Eβˆ’03
R4  9.9000E+01 βˆ’4.7407Eβˆ’02  3.5286Eβˆ’02  2.1555Eβˆ’02 βˆ’1.0367Eβˆ’02 3.8535Eβˆ’02 βˆ’2.3572Eβˆ’02 βˆ’9.4160Eβˆ’03 
R5 βˆ’6.3218Eβˆ’01 βˆ’2.8859Eβˆ’01 βˆ’2.9855Eβˆ’02  8.6677Eβˆ’02 βˆ’6.0682Eβˆ’02 2.6559Eβˆ’02  1.1895Eβˆ’01 βˆ’1.0344Eβˆ’01 
R6 βˆ’2.9874Eβˆ’01 βˆ’2.1716Eβˆ’01  3.4961Eβˆ’02 βˆ’2.2312Eβˆ’02  2.1387Eβˆ’02 2.2360Eβˆ’02 βˆ’7.9820Eβˆ’03 βˆ’4.7238Eβˆ’03 
R7  6.9979Eβˆ’01  2.3095Eβˆ’01 βˆ’9.9451Eβˆ’02 βˆ’5.6059Eβˆ’03 βˆ’7.6013Eβˆ’03 4.7292Eβˆ’03  6.5420Eβˆ’03 1.2784Eβˆ’03
R8 βˆ’5.1336E+00 βˆ’1.7734Eβˆ’02 βˆ’1.8206Eβˆ’02 βˆ’3.8275Eβˆ’03 βˆ’2.7793Eβˆ’03 βˆ’2.4071Eβˆ’04   1.5203Eβˆ’03 3.6007Eβˆ’04
R9 βˆ’2.2089E+00 βˆ’5.0774Eβˆ’02  1.2660Eβˆ’02 βˆ’1.9147Eβˆ’03 βˆ’1.7550Eβˆ’04 βˆ’1.0073Eβˆ’05   1.5679Eβˆ’05 βˆ’1.4069Eβˆ’06 
R10 βˆ’4.0248Eβˆ’01  8.2286Eβˆ’02 βˆ’1.4477Eβˆ’02  8.5163Eβˆ’04  3.8834Eβˆ’05 βˆ’2.1039Eβˆ’05   2.3218Eβˆ’07 0.0000E+00
R11 βˆ’4.9106E+00 βˆ’3.6428Eβˆ’02  4.2842Eβˆ’03  6.5874Eβˆ’04 βˆ’3.0464Eβˆ’05 βˆ’1.8770Eβˆ’05  βˆ’2.6436Eβˆ’06 6.2277Eβˆ’07
R12 βˆ’3.9329E+01 βˆ’3.2132Eβˆ’02  4.1502Eβˆ’03 βˆ’2.9054Eβˆ’04 βˆ’1.3931Eβˆ’05 3.8620Eβˆ’06  3.1654Eβˆ’08 βˆ’3.5846Eβˆ’08 

Table 11 and table 12 show the inflexion points and the arrest point design data of the camera optical lens 30 lens in embodiment 3 of the present invention.

TABLE 11
Inflexion
Inflexion point number Inflexion point position 1 point position 2
P1R1 1 0.635
P1R2 1 0.625
P2R1 0
P2R2 2 0.645 0.975
P3R1 1 0.265
P3R2 1 0.395
P4R1 0
P4R2 1 1.195
P5R1 1 0.875
P5R2 2 0.925 1.265
P6R1 0
P6R2 1 0.565

TABLE 12
Arrest
Arrest point number Arrest point position 1 point position 2
P1R1 0
P1R2 0
P2R1 0
P2R2 1 0.835
P3R1 1 0.455
P3R2 1 0.685
P4R1 0
P4R2 0
P5R1 1 1.545
P5R2 0
P6R1 0
P6R2 1 1.105

FIG. 10 and FIG. 11 show the longitudinal aberration and lateral color schematic diagrams after light with a wavelength of 470 nm, 555 nm and 650 nm passes the camera optical lens 30 in the third embodiment. FIG. 12 shows the field curvature and distortion schematic diagrams after light with a wavelength of 555 nm passes the camera optical lens 30 in the third embodiment.

As shown in Table 13, the third embodiment satisfies the various conditions.

In this embodiment, the pupil entering diameter of the camera optical lens is 1.804 mm, the full vision field image height is 2.994 mm, the vision field angle in the diagonal direction is 76.31Β°, it has wide-angle and is ultra-thin, its on-axis and off-axis chromatic aberrations are fully corrected, and it has excellent optical characteristics.

TABLE 13
Embodiment 1 Embodiment 2 Embodiment 3
f 3.805 3.801 3.788
f1 βˆ’11.397 βˆ’7.982 βˆ’6.637
f2 2.748 2.587 2.379
f3 βˆ’6.000 βˆ’11.441 βˆ’13.597
f4 6.417 4.636 54.044
f5 3.489 3.864 2.464
f6 βˆ’1.887 βˆ’1.606 βˆ’1.557
f12 3.756 3.933 3.964
(R1 + R2)/(R1 βˆ’ R2) 6.300 5.102 5.694
(R3 + R4)/(R3 βˆ’ R4) βˆ’0.658 βˆ’0.613 βˆ’0.926
(R5 + R6)/(R5 βˆ’ R6) βˆ’0.475 3.468 4.983
(R7 + R8)/(R7 βˆ’ R8) 4.308 3.970 βˆ’50.784
(R9 + R10)/ 0.098 0.639 0.153
(R9 βˆ’ R10)
(R11 + R12)/ βˆ’0.507 0.050 βˆ’0.322
(R11 βˆ’ R12)
f1/f βˆ’2.995 βˆ’2.100 βˆ’1.752
f2/f 0.722 0.681 0.628
f3/f βˆ’1.577 βˆ’3.010 βˆ’3.589
f4/f 1.686 1.220 14.266
f5/f 0.917 1.017 0.650
f6/f βˆ’0.496 βˆ’0.422 βˆ’0.411
f12/f 0.987 1.035 1.046
d1 0.240 0.240 0.245
d3 0.620 0.626 0.615
d5 0.483 0.230 0.234
d7 0.525 0.645 0.361
d9 0.770 0.751 0.947
d11 0.250 0.240 0.230
Fno 2.100 2.100 2.100
TTL 5.197 5.200 4.901
d1/TTL 0.046 0.046 0.050
d3/TTL 0.119 0.120 0.126
d5/TTL 0.093 0.044 0.048
d7/TTL 0.101 0.124 0.074
d9/TTL 0.148 0.144 0.193
d11/TTL 0.048 0.046 0.047
n1 1.7174 1.8052 2.0018
n2 1.5445 1.5445 1.5445
n3 1.6510 1.6510 1.6510
n4 1.5352 1.5352 1.6613
n5 1.5352 1.5352 1.5352
n6 1.7130 1.7725 1.8820
v1 29.5005 25.4564 19.3250
v2 55.9870 55.9870 55.9870
v3 21.5136 21.5136 21.5136
v4 56.0934 56.0934 20.3729
v5 56.0934 56.0934 56.0934
v6 53.9383 49.5029 37.2213

It is to be understood, however, that even though numerous characteristics and advantages of the present exemplary embodiments have been set forth in the foregoing description, together with details of the structures and functions of the embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms where the appended claims are expressed.

Claims

What is claimed is:

1. A camera optical lens comprising, from an object side to an image side in sequence: a first lens, a second lens having a positive refractive power, a third lens having a negative refractive power, a fourth lens, a fifth lens, and a sixth lens; wherein the camera optical lens further satisfies the following conditions:


βˆ’3≀f1/fβ‰€βˆ’1.7;


1.7≀n1≀2.2;


1.7≀n6≀2.2;

where

f: the focal length of the camera optical lens;

f1: the focal length of the first lens;

n1: the refractive power of the first lens;

n6: the refractive power of the sixth lens.

2. The camera optical lens as described in claim 1, wherein the first lens is made of glass material, the second lens is made of plastic material, the third lens is made of plastic material, the fourth lens is made of plastic material, the fifth lens is made of plastic material, the sixth lens is made of glass material.

3. The camera optical lens as described in claim 1 further satisfying the following conditions:


βˆ’2.997≀f1/fβ‰€βˆ’1.73;


1.709≀n1≀2.06;


1.707≀n6≀2.04.

4. The camera optical lens as described in claim 1, wherein first lens has a negative refractive power with a convex object side surface and a concave image side surface; the camera optical lens further satisfies the following conditions:


2.55≀(R1+R2)/(R1βˆ’R2)≀9.45;


0.12≀d1≀0.37; where

R1: the curvature radius of object side surface of the first lens;

R2: the curvature radius of image side surface of the first lens.

d1: the thickness on-axis of the first lens.

5. The camera optical lens as described in claim 4 further satisfying the following conditions:


4.08≀(R1+R2)/(R1βˆ’R2)≀7.56;


0.19≀d1≀0.29.

6. The camera optical lens as described in claim 1, wherein the second lens has a convex object side surface and a convex image side surface; the camera optical lens further satisfies the following conditions:


0.31≀f2/f≀1.08;


βˆ’1.85≀(R3+R4)/(R3βˆ’R4)β‰€βˆ’0.41;


0.31≀d3≀0.94; where

f: the focal length of the camera optical lens;

f2: the focal length of the second lens;

R3: the curvature radius of the object side surface of the second lens;

R4: the curvature radius of the image side surface of the second lens;

d3: the thickness on-axis of the second lens.

7. The camera optical lens as described in claim 6 further satisfying the following conditions:


0.5≀f2/f≀0.87;


βˆ’1.16≀(R3+R4)/(R3βˆ’R4)β‰€βˆ’0.51;


0.49≀d3≀0.75.

8. The camera optical lens as described in claim 1, wherein the third lens has a concave image side surface; the camera optical lens further satisfies the following conditions:


βˆ’7.18≀f3/fβ‰€βˆ’1.05;


βˆ’0.95≀(R5+R6)/(R5βˆ’R6)≀7.47;


0.12≀d5≀0.72; where

f: the focal length of the camera optical lens;

f3: the focal length of the third lens;

R5: the curvature radius of the object side surface of the third lens;

R6: the curvature radius of the image side surface of the third lens;

d5: the thickness on-axis of the third lens.

9. The camera optical lens as described in claim 8 further satisfying the following conditions:


βˆ’4.49≀f3/fβ‰€βˆ’1.31;


βˆ’0.59≀(R5+R6)/(R5βˆ’R6)≀5.98;


0.18≀d5≀0.58.

10. The camera optical lens as described in claim 1, wherein the fourth lens has a positive refractive power with a concave object side surface and a convex image side surface; the camera optical lens further satisfies the following conditions:


0.61≀f4/f≀21.4;


βˆ’101.57≀(R7+R8)/(R7βˆ’R8)≀6.46;


0.18≀d7≀0.97; where

f: the focal length of the camera optical lens;

f4: the focal length of the fourth lens;

R7: the curvature radius of the object side surface of the fourth lens;

R8: the curvature radius of the image side surface of the fourth lens;

d7: the thickness on-axis of the fourth lens.

11. The camera optical lens as described in claim 10 further satisfying the following conditions:


0.98≀f4/f≀17.12;


βˆ’63.48≀(R7+R8)/(R7βˆ’R8)≀5.17;


0.29≀d7≀0.77.

12. The camera optical lens as described in claim 1, wherein the fifth lens has a positive refractive power with a convex object side surface and a convex image side surface; the camera optical lens further satisfies the following conditions:


0.33≀f5/f≀1.52;


0.05≀(R9+R10)/(R9βˆ’R10)≀0.96;


0.38≀d9≀1.42; where

f: the focal length of the camera optical lens;

f5: the focal length of the fifth lens;

R9: the curvature radius of the object side surface of the fifth lens;

R10: the curvature radius of the image side surface of the fifth lens;

d9: the thickness on-axis of the fifth lens.

13. The camera optical lens as described in claim 12 further satisfying the following conditions:


0.52≀f5/f≀1.22;


0.08≀(R9+R10)/(R9βˆ’R10)≀0.77;


0.6≀d9≀1.14.

14. The camera optical lens as described in claim 1, wherein the sixth lens has a negative refractive power with a concave object side surface and a concave image side surface; the camera optical lens further satisfies the following conditions:


βˆ’0.99≀f6/fβ‰€βˆ’0.27;


βˆ’1.01≀(R11+R12)/(R11βˆ’R12)≀0.08;


0.11≀d11≀0.38; where

f: the focal length of the camera optical lens;

f6: the focal length of the sixth lens;

R11: the curvature radius of the object side surface of the sixth lens;

R12: the curvature radius of the image side surface of the sixth lens;

d11: the thickness on-axis of the sixth lens.

15. The camera optical lens as described in claim 14 further satisfying the following conditions:


βˆ’0.62≀f6/fβ‰€βˆ’0.34;


βˆ’0.63≀(R11+R12)/(R11βˆ’R12)≀0.06;


0.18≀d11≀0.3.

16. The camera optical lens as described in claim 1 further satisfying the following condition:


0.49≀f12/f≀1.57; where

f12: the combined focal length of the first lens and the second lens;

f: the focal length of the camera optical lens.

17. The camera optical lens as described in claim 16 further satisfying the following condition:


0.79≀f12/f≀1.26.

18. The camera optical lens as described in claim 1, wherein the total optical length TTL of the camera optical lens is less than or equal to 5.72 mm.

19. The camera optical lens as described in claim 18, wherein the total optical length TTL of the camera optical lens is less than or equal to 5.46 mm.

20. The camera optical lens as described in claim 1, wherein the aperture F number of the camera optical lens is less than or equal to 2.16.

21. The camera optical lens as described in claim 20, wherein the aperture F number of the camera optical lens is less than or equal to 2.12.

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