# Patent

## Title
Camera lens

## Abstract

A camera lens includes, lined up from the object side to the image side, a first lens with positive refractive power, a second lens with negative refractive power, a third lens with negative refractive power, a fourth lens with positive refractive power, a fifth lens with positive refractive power, and a sixth lens with positive refractive power. The camera lens satisfies specific conditions.

## Background
FIELD OF THE INVENTION
The present disclosure is related to a camera lens, and more particularly to a camera lens comprising 6 lenses.
DESCRIPTION OF RELATED ART
In recent years, a variety of cameras equipped with CCD, CMOS or other camera elements are widely popular. Along with the development of miniature and high performance camera elements, the ultrathin and high-luminous flux (Fno) wide-angle camera lenses with excellent optical properties are needed in society.
The technology related to the camera lens composed of six ultra-thin, high-luminous flux f value (Fno) wide angle lenses with excellent optical properties is developed gradually. The camera lens mentioned in the proposal is composed of 6 lenses, lined up from the object side as follows: a first lens with positive refractive power, a second lens with negative refractive power, a third lens with negative refractive power, a fourth lens with positive refractive power, a fifth lens with positive refractive power, a sixth lens with negative refractive power.
The camera lens in embodiments 1 to 3 in the special published bulletin No. 2014-052631 is composed of 6 lenses described above, but the distribution of the refractive power of the second lens and the shape of the third lens are inadequate, therefore TTL/IH≧1.941, and ultrathin degree is not sufficient.
The camera lens disclosed in embodiments 1 to 3 of Japan patent document No. 5651881 is composed of 6 lenses, but, the distribution of the refractive power of the second lens and the third lens, the shape of the second lens are inadequate, therefore TTL/IH≧1.464 and ultrathin degree is not sufficient.
Therefore, it is necessary to provide a new camera lens to overcome the problems mentioned above.



BRIEF DESCRIPTION OF THE DRAWINGS
Many aspects of the embodiments can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.
FIG. 1 is the structure diagram of a camera lens LA in the present invention.
FIG. 2 is the structure diagram of a camera lens LA in the embodiment 1.
FIG. 3 is the diagram of the spherical aberration (axial chromatic aberration) of camera lens LA of embodiment 1 in the present invention.
FIG. 4 is the diagram of the magnification chromatic aberration of the camera lens LA in the embodiment 1.
FIG. 5 is the diagram of the image side curving and distortion aberration of the camera lens LA in the embodiment 1.
FIG. 6 is the structural diagram of the camera lens LA in the embodiment 2.
FIG. 7 is the diagram of the spherical aberration (axial chromatic aberration) of camera lens LA of embodiment 2 in the present invention.
FIG. 8 is the diagram of the magnification chromatic aberration of the camera lens LA in the embodiment 2.
FIG. 9 is the diagram of the image side curving and distortion aberration of the camera lens LA in the embodiment 2.
FIG. 10 is the structural diagram of the camera lens LA in the embodiment 3.
FIG. 11 is the diagram of the spherical aberration (axial chromatic aberration) of camera lens LA of embodiment 3 in the present invention.
FIG. 12 is the diagram of the magnification chromatic aberration of the camera lens LA in the embodiment 3.
FIG. 13 is the diagram of the image side curving and distortion aberration of camera lens LA of embodiment 3.



DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS
The present invention will hereinafter be described in detail with reference to exemplary embodiments. To make the technical problems to be solved, technical solutions and beneficial effects of present disclosure more apparent, the present disclosure is described in further detail together with the figures and the embodiments. It should be understood the specific embodiments described hereby is only to explain this disclosure, not intended to limit this disclosure.
The camera lens in one embodiment of the present invention is explained with design drawings. FIG. 1 shows the structural diagram of one embodiment of the camera lens of the present invention. The camera lens LA is composed of 6 lenses which are lined up from the object side to the image side in turn as follows: an open 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. A glass plate GF is provided between the sixth lens L6 and the imaging plane. The glass plate GF is a cover glass or a light filter with IR cut-off filtration and other functions, or, the glass plate GF is not be provided between the lens L6 and the imaging plane.
The first lens L1 has positive refractive power. The second lens L2 has negative refractive power. The third lens L3 has negative refractive power. The fourth lens L4 has positive refractive power. The fifth lens L5 has positive refractive power. The sixth lens L6 has negative refractive power. In order to correct aberration better, the surface of six lenses is best designed to be non-spherical shape.
The camera lens LA satisfies the following specific conditions (1) to (4).

−2.00≦f2/f≦−1.40  (1)

−10.00≦f3/f≦−4.50  (2)

1.80≦(R3+R4)/(R3−R4)≦4.00  (3)

−15.00≦(R5+R6)/(R5−R6)≦−4.00  (4)

In which:

f: Overall focal distance of the lenses.

f2: The focal distance of the second lens L2.

f3: The focal distance of the third lens L3.

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

R4: The image side curvature radius of the third lens L2.

R5: The image side curvature radius of the third lens L3.

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

The condition expression (1) specifies the negative refractive power of the second lens L2. If the value exceeds the limit of the condition expression (1), along with Fn0≦2.2 ultra-thin and wide-angle development of the lens, it is difficult to correct the axial chromatic aberration.
In addition, the limit of condition expression (1) is better set within the range of the condition expression (1-A) as follows.

−1.85≦f2/f≦−1.48  (1-A)

The condition expression (2) specifies the negative refractive power of the third lens L3. If the value exceeds the limit of the condition expression (2), along with Fn0≦2.2 ultra-thin and wide-angle development of the lens, it is difficult to correct magnification chromatic aberration. In addition, the limit of condition expression (2) is better set within the range of the condition expression (2-A) as follows.

−7.50≦f3/f≦−5.00  (2-A)

The condition expression (3) specifies the shape of the second lens L2. If the value exceeds the limit of the condition expression (3), along with Fn0≦2.2 ultra-thin and wide-angle development of the lens, it is difficult to correct the axial chromatic aberration.
In addition, the limit of condition expression (3) is better set within the range of the condition expression (3-A) as follows.

2.20≦(R3+R4)/(R3−R4)≦3.65  (3-A)

The condition expression (4) specifies the shape of the third lens L3. If the value exceeds the limit of the condition expression (4), along with Fn0≦2.2 ultra-thin and wide-angle development of the lens, it is difficult to correct magnification chromatic aberration.
In addition, the limit of condition expression (4) is better set within the range of the condition expression (4-A) as follows.

−8.00≦(R5+R6)/(R5−R6)≦−4.50  (4-A)

The first lens L1 has positive refractive power and satisfies the following condition expressions (5) and (6).

0.72≦f1/f≦0.85  (5)

−1.80≦(R1+R2)/(R1−R2)≦−0.90  (6)

In which

f: Overall focal distance of the lenses.

f1: The focal distance of the first lens L1.

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

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

The condition expression (5) specifies the positive refractive power of the first lens L1. When exceeding the lower limit value of the condition expression (5), although in favor of the ultra-thin development of the lens, the first lens L1 has too big positive refractive power and it is difficult to correct the aberration and other issues. On the contrary, when exceeding the upper limit, the first lens has too small positive refractive power, not conducive to the ultrathin development of lens.
The condition expression (6) specifies the shape of the first lens L1.
If exceeding the limit of the condition expression (6), along with Fno≦2.2 ultra-thin and wide-angle development of the lens, it is difficult to correct the spherical aberration and other higher aberration issues.
The fourth lens L4 has positive refractive power and satisfies the following condition expression (5).

2.00≦f4/f≦10.00  (7)

In which:

f: Overall focal distance of the lenses.

f4: The focal distance of the fourth lens L4.

The condition expression (7) specifies the positive refractive power of the fourth lens L4. If the value exceeds the limit of the condition expression (7), it is not conducive to the wide angle and ultra-thin development of the lens.
As six lenses of the camera lens LA have the structure described above and meet all condition expressions, the camera lens with 6 high-luminous flux lenses with excellent optical properties, in TTL (optical length)/IH (image height) 1.45, ultra-thin and wide-angle 2ω≧76°, Fno≦2.2 becomes possible.
The camera lens LA of the present invention is described with the embodiments as follows. The symbols in all embodiments are represented as follows. In addition, the unit of the distance, radius and center thickness is mm.
f: Overall focal distance of the camera lens LA.
f1: The focal distance of the first lens L1.
f2: The focal distance of the second lens L2.
f3: The focal distance of the third lens L3.
f4: The focal distance of the fourth lens L4.
f5: The focal distance of the fifth lens L5.
f6: The focal distance of the sixth lens L6.
Fno: F value.
2ω: Total angle of view
S1: Open aperture.
R: The curvature radius of the optical surface is the center curvature radius of lens.
R1: The object side curvature radius of the first lens L2.
R2: The image side curvature radius of the first lens L2.
R3: The object side curvature radius of the third lens L2.
R4: The image side curvature radius of the second lens L2.
R5: The object side curvature radius of the third lens L3.
R6: The image side curvature radius of the third lens L3.
R7: The object side curvature radius of the fourth lens L4.
R8: The image side curvature radius of the fourth lens L4.
R9: The object side curvature radius of the fifth lens L5.
R10: The curvature radius of the image side of the fifth lens L5.
R11: The object side curvature radius of the sixth lens L6
R12: The image side curvature radius of the sixth lens L6.
R13: The object side curvature radius of the glass plate GF;
R14: The image side curvature radius of the glass plate GF;
d: The center thickness of lenses or the distance between lenses.
d0: The axial distance from the open aperture S1 to the object side of the first lens L1.
d1: The center thickness of the first lens L1.
d2: The axial distance between the image side of the first lens L1 and the object side of the second lens L2.
d3: The center thickness of the second lens L2.
d4: The axial distance between the image side of the second lens L2 and the object side of the third lens L3.
d5: The center thickness of the third lens L3.
d6: The axial distance between the image side of the third lens L3 and the object side of the fourth lens L4.
d7: The center thickness of the fourth lens L4.
d8: The axial distance between the image side of the fourth lens L4 and the object side of the fifth lens L5.
d9: The center thickness of the fifth lens L5.
d10: The axial distance between the image side of the fifth lens and the object side of the sixth lens.
d11: The center thickness of the sixth lens L6.
d12: The axial distance between the image side of sixth lens L6 and the object side of the glass plate GF
d13: The center thickness of the glass plate GF.
d14: The axial distance from the image side to the imaging plane of the glass plate GF.
nd: Refractive power of line d.
nd1: Refractive power of line d of the first lens L1
nd2: Refractive power of line d of the second lens L2.
nd3: Refractive power of line d of the third lens L3.
nd4: Refractive power of line d of the fourth lens L4.
nd5: Refractive power of line d of the fifth lens L5.
nd6: The refractive power of line d of the sixth lens L6.
nd7: Refractive power of line d of glass plate GF.
v: Abbe number.
v1: Abbe number of the first lens L1.
v2: Abbe number of the second lens L2.
v3: Abbe number of the third lens L3.
v4: Abbe number of the fourth lens L4.
v5: Abbe number of the fifth lens L5.
v6: Abbe number of the sixth lens L6.
v7: Abbe number of the glass plate GF
TTL: Optical length (the axial distance from the object side to the image side of the first lens L1).
LB: The axial distance from the image side to the imaging plane of the sixth lense. (including glass plate GF)
IH: Image height.

y=(x2/R)/1+{1−(k+1)(x2/R2)}1/2+A4x4+A6x6+A8x8+A10x10+A12x12+A14x14+A16x16  (8)

In which, R is the axial curvature radius. k is the cone constant. A4, A6, A8, A10, A12, A14, A16 are aspherical coefficients.

As a matter of convenience, the aspheric surface of all lenses adopts the aspheric surface in condition expression (8). But, not limited to the polynomial forms of the aspheric surface in condition expression (8).
Embodiment 1
FIG. 2 is the structural diagram of the camera lens LA in the embodiment 1. The curvature radius of the object side and image, center thickness and the distance d between the lenses, refractive power nd and Abbe number v of the first lens, second lens and third lens of the camera lens LA in the embodiment 1 are shown in table 1. The cone constant k and aspherical coefficient are shown in table 2.











TABLE 1






R
d
nd
vd






















S1
∞
d0 =
−0.370






R1
1.76496
d1 =
0.728
nd1
1.5831
v1
59.39


R2
8.67532
d2 =
0.059


R3
8.52752
d3 =
0.248
nd2
1.6448
v2
22.44


R4
3.28049
d4 =
0.512


R5
−5.19223
d5 =
0.229
nd3
1.6397
v3
23.53


R6
−6.93210
d6 =
0.044


R7
13.25596
d7 =
0.465
nd4
1.5441
v4
56.12


R8
−42.16130
d8 =
0.467


R9
−4.88948
d9 =
0.449
nd5
1.5352
v5
56.12


R10
−1.56414
d10 =
0.659


R11
−3.49408
d11 =
0.328
nd6
1.5352
v6
56.12


R12
2.99351
d12 =
0.525


R13
∞
d13 =
0.210
nd7
1.5168
v6
64.17


R14
∞
d14 =
0.352



















TABLE 2









Cone Constant
Aspherical Coefficient
















k
A4
A6
A8
A10
A12
A14
A16



















R1
−2.6457E−01
7.1806E−03
6.3309E−03
−2.6993E−03
1.8000E−03
−1.8153E−04
8.0948E−04
−4.0201E−04


R2
0.0000E+00
−5.9373E−03
−2.7016E−03
8.0058E−03
3.2154E−03
−2.4778E−03
−6.6869E−03
3.2767E−03


R3
−5.1420E+00
−7.6154E−03
7.0223E−03
6.6977E−03
2.8608E−03
−1.9035E−03
−6.9415E−03
3.1617E−03


R4
−2.4752E−01
1.6986E−02
1.0499E−02
1.1448E−02
3.5142E−03
7.6755E−04
1.2648E−03
2.1145E−03


R5
1.4945E+01
−5.2018E−03
−2.7645E−02
5.3154E−03
1.2701E−02
4.6451E−03
−2.0111E−03
1.6147E−03


R6
2.2863E+01
−1.3414E−02
−1.4755E−02
6.6927E−03
7.2883E−03
2.5651E−03
−9.8356E−05
−5.8412E−04


R7
0.0000E+00
−5.2967E−02
9.0012E−03
4.1528E−03
6.6717E−04
−3.4350E−04
−2.9085E−04
4.8092E−05


R8
0.0000E+00
−4.6841E−02
3.2202E−04
6.1492E−04
−9.9929E−05
5.0849E−05
5.9897E−05
3.8758E−06


R9
5.6021E+00
−2.0491E−02
−4.6875E−03
1.0712E−03
−8.0078E−04
−3.7298E−05
4.7146E−05
2.3196E−05


R10
−3.5973E+00
−2.6378E−02
8.2036E−03
−3.7951E−04
4.0294E−05
−1.2623E−05
−2.5586E−06
−2.9441E−07


R11
0.0000E+00
1.5123E−03
1.5066E−03
1.3873E−05
−7.0564E−06
−1.2349E−07
2.2066E−08
8.7553E−10


R12
−2.5742E+01
−1.8468E−02
2.0437E−03
−2.8494E−04
1.2543E−05
2.1677E−07
−5.5634E−09
1.2351E−11









The values of the embodiments 1-3 and the corresponding values of the parameters specified in the conditions (1)-(7) are listed in table 7.
As shown in table 7, the embodiment 1 satisfies the condition expressions (1) to (7).
FIG. 3 is the diagram of the spherical aberration (axial chromatic aberration) of the camera lens LA in the embodiment 1. FIG. 4 is the diagram of the magnification chromatic aberration. FIG. 5 is the diagram of the image side curving and distortion aberration. In addition, the image side curving S in
FIG. 5 is the image side curving relative to sagittal plane. T is the image side curving relative to the tangent image side. It is same also in embodiment 2 and 3. In embodiment 1, the camera lens LA with 2ω=78.1°, TTL/IH=1.409, Fno=2.05 ultra-thin, high-luminous flux wide-angle lenses, as shown in FIGS. 3-5, is easy to understand that it has excellent optical properties.
Embodiment 2
FIG. 6 is the structural diagram of the camera lens LA in the embodiment 2. The curvature radius R of the object side and image side of the first lens L1 to the sixth lens L6, center thickness of the lenses and the distance d between the lenses, refractive power nd and Abbe number v of the camera lens LA in the embodiment 2 are shown in table 3. The cone constant k and aspherical coefficient are shown in table 4.













TABLE 3







R
d

nd
vd























S1
∞
d0 =
−0.250






R1
2.05855
d1 =
0.667
nd1
1.5831
v1
59.39


R2
−162.13476
d2 =
0.053


R3
8.31674
d3 =
0.246
nd2
1.6448
v2
22.44


R4
3.13480
d4 =
0.526


R5
−5.20424
d5 =
0.238
nd3
1.6397
v3
23.53


R6
−7.00949
d6 =
0.048


R7
25.15081
d7 =
0.443
nd4
1.5441
v4
56.12


R8
−31.86314
d8 =
0.469


R9
−5.10336
d9 =
0.400
nd5
1.5352
v5
56.12


R10
−1.54692
d10 =
0.745


R11
−3.51704
d11 =
0.334
nd6
1.5352
v6
56.12


R12
2.99421
d12 =
0.525


R13
∞
d13 =
0.210
nd7
1.5168
v6
64.17


R14
∞
d14 =
0.367



















TABLE 4









Cone Constant
Aspherical Coefficient
















k
A4
A6
A8
A10
A12
A14
A16



















R1
−3.9914E−01
5.1347E−03
3.9935E−03
−4.3998E−03
7.0123E−04
−9.0193E−04
3.1784E−04
−7.5250E−04


R2
0.0000E+00
−3.4547E−03
−1.5884E−03
7.8018E−03
2.5746E−03
−3.1407E−03
−7.1772E−03
2.9993E−03


R3
7.2080E+00
−5.3285E−03
9.2349E−03
8.4584E−03
4.0817E−03
−1.1852E−03
−6.5897E−03
3.2996E−03


R4
−1.0918E+00
1.3975E−02
1.7355E−03
5.8184E−03
6.3352E−04
−4.7554E−04
8.5234E−04
2.0577E−03


R5
1.5408E+01
−6.2889E−03
−2.7558E−02
5.0151E−03
1.2420E−02
4.4756E−03
−2.2259E−03
1.3892E−03


R6
2.0552E+01
−1.2089E−02
−1.4051E−02
6.9773E−03
7.3500E−03
2.5705E−03
−8.6067E−05
−5.6191E−04


R7
0.0000E+00
−5.3613E−02
9.0270E−03
4.2467E−03
6.8994E−04
−4.1299E−04
−3.0380E−04
6.8197E−05


R8
0.0000E+00
−4.7013E−02
4.6574E−04
7.8162E−04
−1.0260E−05
7.6555E−05
5.2526E−05
−9.8378E−06


R9
5.6964E+00
−2.0286E−02
−4.8657E−03
9.9562E−04
−8.2468E−04
−4.4750E−05
4.4676E−05
2.2299E−05


R10
−3.4719E+00
−2.6178E−02
8.3300E−03
−3.3935E−04
5.1703E−05
−9.4344E−06
−1.6710E−06
−5.0991E−08


R11
0.0000E+00
1.5489E−03
1.5094E−03
1.4222E−05
−7.0229E−06
−1.1995E−07
2.2591E−08
9.9851E−10


R12
−2.2946E+01
−1.8454E−02
2.0477E−03
−2.8499E−04
1.2485E−05
2.0698E−07
−6.8141E−09
−1.3310E−10









As shown in table 7, the embodiment 2 satisfies the condition expressions (1) to (7).
FIG. 7 is the diagram of the spherical aberration (axial chromatic aberration) of the camera lens LA in the embodiment 2. FIG. 8 is the diagram of the magnification chromatic aberration. FIG. 9 is the diagram of the image side curving and distortion aberration. As shown in FIGS. 7 to 9, for full image angle 2ω=79.2°, TTL/IH=1.408, Fno=2.05 ultra-thin, high-luminous flux wide-angle lenses of the camera lens LA in the embodiment 2 are easy to understand that they have excellent optical properties.
Embodiment 3
FIG. 10 is the structural diagram of the camera lens LA in the embodiment 3. The curvature radius R of the object side and image side of the first lens L1 to the sixth lens L6, center thickness of the lenses and the distance d between the lenses, refractive power nd and Abbe number v of the camera lens LA in the embodiment 3 are shown in table 5. The cone constant k and aspherical coefficient are shown in table 6.












TABLE 5







R
d
nd
vd























S1
∞
d0 =
−0.340






R1
1.85014
d1 =
0.693
nd1
1.5831
v1
59.39


R2
12.98282
d2 =
0.054


R3
8.21719
d3 =
0.240
nd2
1.6448
v2
22.44


R4
3.08138
d4 =
0.488


R5
−5.14525
d5 =
0.240
nd3
1.6397
v3
23.53


R6
−7.31498
d6 =
0.048


R7
11.73945
d7 =
0.513
nd4
1.5441
v4
56.12


R8
−11.59443
d8 =
0.530


R9
−4.60912
d9 =
0.417
nd5
1.5352
v5
56.12


R10
−1.59258
d10 =
0.641


R11
−3.44315
d11 =
0.330
nd6
1.5352
v6
56.12


R12
2.90999
d12 =
0.525


R13
∞
d13 =
0.210
nd7
1.5168
v6
64.17


R14
∞
d14 =
0.315



















TABLE 6









Cone Constant
Aspherical Coefficient
















k
A4
A6
A8
A10
A12
A14
A16



















R1
−2.7852E−01
7.3839E−03
5.5077E−03
−2.8976E−03
1.7625E−03
−2.5232E−04
6.6166E−04
−6.0391E−04


R2
0.0000E+00
−7.7522E−03
−1.7226E−03
8.1227E−03
3.0129E−03
−2.6824E−03
−6.8245E−03
3.2187E−03


R3
−1.3156E+01
−9.2638E−03
5.3509E−03
6.8432E−03
3.4362E−03
−1.4272E−03
−6.6749E−03
3.2726E−03


R4
−7.0467E−01
1.5119E−02
9.2835E−03
9.2141E−03
2.0401E−03
6.7868E−05
1.0864E−03
2.2099E−03


R5
1.4708E+01
−2.9712E−03
−2.5768E−02
5.8409E−03
1.2638E−02
4.6549E−03
−1.9855E−03
1.4996E−03


R6
2.3219E+01
−1.3800E−02
−1.5386E−02
6.4132E−03
7.1404E−03
2.4223E−03
−2.3378E−04
−6.7842E−04


R7
0.0000E+00
−5.2888E−02
9.1069E−03
4.0982E−03
5.7745E−04
−4.3429E−04
−3.0353E−04
7.0333E−05


R8
0.0000E+00
−4.4853E−02
2.4082E−05
4.3692E−04
−8.9891E−05
7.9119E−05
7.7391E−05
1.2703E−05


R9
5.4730E+00
−2.1679E−02
−4.7642E−03
1.1528E−03
−7.5970E−04
−2.7027E−05
4.8647E−05
2.2901E−05


R10
−3.7237E+00
−2.6449E−02
8.1111E−03
−4.1930E−04
3.1869E−05
−1.4001E−05
−2.7097E−06
−2.8304E−07


R11
0.0000E+00
1.4508E−03
1.5112E−03
1.5098E−05
−6.9538E−06
−1.1876E−07
2.1807E−08
7.9746E−10


R12
−2.3465E+01
−1.8288E−02
2.0952E−03
−2.8188E−04
1.2541E−05
2.0988E−07
−6.2247E−09
−1.8842E−11









As shown in table 7, the embodiment 3 satisfies the condition expressions (1) to (7).
FIG. 11 is the diagram of the spherical aberration (axial chromatic aberration) of the camera lens LA in the embodiment 3. FIG. 12 is the diagram of the magnification chromatic aberration. FIG. 13 is the diagram of the image side curving and distortion aberration. In embodiment 3, the camera lens LA with 2ω=79.7°, TTL/IH=1.401, Fno=2.05 ultra-thin, high-luminous flux wide-angle lenses, as shown in FIGS. 11 to 13, is easy to understand that it has excellent optical properties.
The values of the embodiments and the corresponding values of the parameters specified in conditions (1) to (7) are listed in table 7. In addition, the units in table 7 are 2ω(°), f(mm), f1(mm), f2(mm), f3(mm), f4(mm), f5(mm), f6(mm), TTL(mm), LB(mm), IH(mm).











TABLE 7






Embodiment 1
Embodiment 2
Embodiment 3
Condition



















f2/f
−1.85
−1.79
−1.77
(1)


f3/f
−7.49
−7.49
−6.44
(2)


(R3 + R4)/
2.25
2.21
2.20
(3)


(R3 − R4)






(R5 + R6)/
−6.97
−6.77
−5.74
(4)


(R5 − R6)






f1/f
0.80
0.79
0.82
(5)


(R1 + R2)/
−1.51
−0.97
−1.33
(6)


(R1 − R2)






f4/f
4.08
5.83
2.46
(7)


Fno
2.05
2.05
2.05



2ω
78.1
79.2
79.7



TTL/IH
1.409
1.408
1.401



f
4.554
4.445
4.401



f1
3.658
3.491
3.617



f2
−8.425
−7.951
−7.789



f3
−34.088
−33.300
−28.338



f4
18.590
25.904
10.805



f5
4.104
3.991
4.338



f6
−2.690
−2.969
−2.894



TTL
5.275
5.271
5.244



LB
1.087
1.102
1.050



IH
3.744
3.744
3.744









DESCRIPTION OF SYMBOLS


    LA: Camera lens.
    S1: Open aperture.
    L1: The first lens.
    L2: The second lens.
    L3: The third lens.
    L4: The fourth lens.
    L5: The fifth lens.
    L6: The sixth lens.
    GF: G glass plate.
    R1: The object side curvature radius of the first lens L1.
    R2: The image side curvature radius of the first lens L1.
    R3: The object side curvature radius of the second lens L2.
    R4: The image side curvature radius of the second lens L2.
    R5: The object side curvature radius of the third lens L3.
    R6: The image side curvature radius of the third lens L3.
    R7: The object side curvature radius of the fourth lens L4.
    R8: The image side curvature radius of the fourth lens L4.
    R9: The object side curvature radius of the fifth lens L5.
    R10: The image side curvature radius of the fifth lens L5.
    R11: The object side curvature radius of the sixth lens L6.
    R12: The image side curvature radius of the sixth lens L6.
    R13: The object side curvature radius of the glass plate GF
    R14: The curvature radius of the image side of imaging glass plate GF.
    d: The center thickness of lenses and the distance between lenses.
    d1: The center thickness of the first lens L1.
    d2: The distance from the image side of the first lens L1 to the open aperture S1
    d3: The axial distance from the open aperture S1 to the object side of second lens L2
    d4: The center thickness of the second lens L2
    d5: The axial distance between the image side of the second lens L2 and the object side of the third lens L3.
    d6: The center thickness of the third lens L3.
    d7: The axial distance between the image side of the third lens L3 and the object side of the fourth lens L4.
    d8: The center thickness of the fourth lens L4.
    d9: The axial distance between the image side of the fourth lens L4 and the object side of the fifth lens L5.
    d10: The center thickness of the fifth lens L5.
    d11: The axial distance between the image side of fifths lens L5 and the object side of sixth lens L6.
    d12: The center thickness of the sixth lens L6.
    d13: The axial distance between the image side of sixth lens L6 and the object side of the glass plate GF.
    d14: The center thickness of the glass plate GF.
    d15: The axial distance from the image side to the imaging plane of the glass plate GF.


It is to be understood, however, that even though numerous characteristics and advantages of the present 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 in which the appended claims are expressed.

## Claims

1. A camera lens comprising, lined up from the object side to the image side, a first lens with positive refractive power, a second lens with negative refractive power, a third lens with negative refractive power, a fourth lens with positive refractive power, a fifth lens with positive refractive power, and a sixth lens with positive refractive power, wherein
the camera lens satisfies the following conditions (1)-(4):


−2.00f2/f−1.40  (1)



−10.00<f3/f−4.50  (2)



1.80<(R3+R4)/(R3−R4)<4.00  (3)



−15.00<(R5+R6)/(R5−R6)<−4.00  (4)


In which:
f: Overall focal distance of the lenses
f2: The focal distance of the second lens L2
f3: The focal distance of the third lens L3
R3: The curvature radius of the object side of the second lens L2
R4: The image side curvature radius of the second lens L2
R5: The image side curvature radius of the third lens L3
R6: The image side curvature radius of the third lens L3.

2. The camera lens according to claim 1 further satisfying the following conditions (5)-(6):


0.72<f1/f<0.85  (5)



−1.80<(R1+R2)/(R1−R2)<−0.90  (6)

In which:
f: Overall focal distance of the lenses
f1: The focal distance of the first lens L1
R1: The object side curvature radius of the first lens L1
R2: The image side curvature radius of the first lens L1.

3. The camera lens according to claim 1 further satisfying the following condition (7):


2.00≦f4/f≦10.00  (7)

In which:
f: Overall focal distance of the lenses
f4: The focal distance of the fourth lens L4.