KR20210043926A - Optical Lens for wide angle camera - Google Patents

Abstract

The present invention relates to an optical system for a wide angle camera including: a first lens (10) having a convex surface on an object side and having a concave surface on an upper side; a second lens (20) having a concave surface (R3) on the object side and having a convex surface (R4) on an upper side; a third lens (30) having a convex surface (R5) on the object side and having a convex surface (R6) on an upper side; a fourth lens (40) having a convex surface (R7) on the object side and having a convex surface (R8) on an upper side; a fifth lens (50) having a concave surface (R8) on the object side and having a concave surface (R9) on an upper side; an IR cutoff filter (60) disposed in front of the upper side of the fifth lens (50) and removing light in an infrared (IR) region for picture quality improvement; and an aperture (70) selectively converging light with an infrared region removed that selectively converges light incident from the first lens (10). Each of the lenses (10, 20, 30, 40, 50) is an aspherical lens.

Description

Optical Lens for wide angle camera

The present invention relates to an optical system for a wide-angle camera, and in more detail, it is excellent in securing the amount of ambient light, easy to install in a narrow space, and exhibits improved optical performance compared to the existing ultra-miniature wide-angle cameras, and meets the demands of the upcoming market. It relates to an optical system for wide-angle cameras that can be used for universal use in CCD or CMOS cameras while simultaneously satisfying the miniaturization of the size and cost reduction.

In general, a wide angle camera uses a lens with an angle of view of more than 85 degrees and is suitable for shooting in a wide range, and a CCD camera using a charge coupled device (CCD) and a CMOS using a Complementary Metal Oxide Semiconductor (CMOS) An example is a camera.

However, the lens used in the wide-angle camera is usually made of glass material, which acts as a factor that increases the cost, and also, the amount of ambient light is significantly reduced to less than 30% to less than 60% due to the occurrence of curvature or distortion of the image surface. There was a problem of greatly deteriorating the optical performance of the camera due to the sikim.

In particular, a lens with an ambient light intensity of 70% or more should be used in a CMOS camera for its optical performance, and its application has been difficult, and development of a lens suitable for a CMOS camera has not been made until now.

Further, as the market is rapidly growing and application fields are diversified accordingly, the image sensor technology is improved and more excellent optical performance is required, and the development of smaller lenses is required.

KR 10-0712373 B

It is an object of the present invention to solve the above problems, and the object of the present invention is to have an ambient light ratio of 90% or more so that the difference in brightness between the center of the lens and the surrounding can be eliminated, but applied to a CCD or CMOS camera. It is to provide an optical system for a wide-angle camera that can be used.

In addition, another object of the present invention is to provide an optical system for a wide-angle camera in which the optical performance can be improved while making it easy to mount in a narrow space by making a small size and reducing the optical electric field compared to the conventional one.

Further, another object of the present invention is to improve optical performance through proper use of an aspherical surface, as well as to reduce the number of components provided, and to achieve the performance required by the market. It is to provide an optical system.

The optical system for a wide-angle camera according to the present invention for achieving the above object has a first lens 10 having a convex surface on the object side and a concave surface on the image side, and a concave surface R3 on the object side, and A second lens 20 having a convex surface R4, a third lens 30 having a convex surface R5 on the object side and a convex surface R6 on the image side, and a convex surface R7 on the object side And a fourth lens 40 having a convex surface R8 on the image side, a fifth lens 50 having a concave surface R8 on the object side and a concave surface R9 on the image side, and the fifth lens. Arranged in front of the upper side of the lens 50, the IR cutoff filter 60 that removes light in the infrared (IR) region and the infrared region that selectively converges the light incident from the first lens 10 to improve image quality are removed. It includes a diaphragm 70 for selectively converging the generated light, and the lenses 10, 20, 30, 40, and 50 are all aspherical lenses.

When the focal length of the entire lens system is f and the rear focal length is B, the condition of 1.0 ≤ B/f ≤ 2.0 is satisfied.

When the distance from the first lens surface to the last lens surface of the optical system is T and the focal length of the entire lens system is f, the condition of 3.5 ≤ T/f ≤ 7.0 is satisfied.

According to the present invention, all the objects of the present invention described above can be achieved.

According to the optical system for a wide-angle camera according to the present invention, by using a combination of four exit aspherical surfaces, the resolution is improved from 1M to 4M and manufacturing cost is reduced.

The present invention can realize miniaturization of the optical system by reducing the overall length, and at the same time, not only reducing the manufacturing cost by arranging the entire lens as an aspherical lens, but also securing an ambient light ratio of 90% or more, thereby reducing the brightness of the center and surroundings of the lens. It is possible to solve the difference to the object so that a clear image of the object can be obtained, and it can be applied to both CCD and CMOS cameras.

In addition, the present invention can be easily installed in a narrow space due to the implementation of miniaturization, and the application range can be widened, and the formation of a wide angle of view and aberration correction exhibit good performance.

Furthermore, the present invention not only enables improved and stable optical performance through proper use of an aspheric surface, but also reduces components compared to the existing configuration, as well as reduces material cost, thus providing the performance required by the market. It can be said that it did.

1 is a view showing an optical system characterized by an angle of view of 151.6 degrees in the arrangement state of the optical system for a wide-angle camera according to the present invention.
2 is a view showing an optical system characterized by an angle of view of 141.1 degrees in the arrangement state of the optical system for a wide-angle camera according to the present invention.
3 is a view showing an optical system characterized by an angle of view of 151.6 degrees in the arrangement state of the optical system for a wide-angle camera according to the present invention.
4 is a view showing an optical system characterized by an angle of view of 151.6 degrees in the arrangement state of the optical system for a wide-angle camera according to the present invention.
5 is a view showing an optical system characterized by an angle of view of 120.9 degrees in the arrangement state of the optical system for a wide-angle camera according to the present invention.
6 is a view showing an optical system characterized by an angle of view of 141.9 degrees in the arrangement state of the optical system for a wide-angle camera according to the present invention.
7 is a view showing to explain a sag (Sag) of the aspherical lens of the optical system for a surveillance camera according to the present invention.
8A to 8D are views showing aberration characteristics of an optical system characterized by the angle of view shown in FIG. 1;
9A to 9D are views showing aberration characteristics of an optical system characterized by the angle of view shown in FIG. 2;
10A to 10D are views showing aberration characteristics of an optical system characterized by the angle of view shown in FIG. 3;
11A to 11D are views showing aberration characteristics of an optical system characterized by the angle of view shown in FIG. 4;
12A to 12D are views showing aberration characteristics of an optical system characterized by the angle of view shown in FIG. 5;
13A to 13D are views showing aberration characteristics of an optical system characterized by the angle of view shown in FIG. 6.

Hereinafter, the configuration and operation of the embodiment according to the present invention will be described in detail with reference to the drawings.

As shown in Figs. 1 to 6, the optical system for a wide-angle camera using an aspherical surface according to the present invention is configured to have the same components, but by adjusting the design variables of the components including the aspherical surface, the angle of view to the field of view) It is an optical system that has a difference in processing.

First, referring to FIG. 1, the optical system of the present invention is a negative [(-)Power] magnification lens having a convex surface (R1) on the object side and a concave surface (R2) on the image side, and aspheric surfaces having aspherical surfaces on both sides. The first lens 10, which is a lens, is a positive [(+) Power] magnification lens having a concave surface R3 on the object side and a convex surface R4 on the image side, and a second aspherical lens having an aspherical surface on both sides. The lens 20 is a positive [(+)Power] magnification lens having a convex surface R5 on the object side and a convex surface R6 on the image side, and a third lens, which is an aspherical lens having an aspherical surface on both sides. 30) The fourth lens 40, which is a negative [(-)Power] magnification lens having a convex surface R7 on the object side and a convex surface R8 on the image side, and an aspherical lens having aspherical surfaces on both sides. ), in front of the image side of the fifth lens 50 and the fifth lens 50, which are negative [(-)Power] magnification lenses having a concave surface R8 on the object side and a concave surface R9 on the image side. The IR cutoff filter 60 that removes light from the infrared (IR) region and the infrared region that selectively converges the light incident from the first lens 10 to selectively converge the removed light to improve image quality. Includes one stop (70).

In front of the image side of the fifth lens 50, a window glass 80 for protecting the image pickup device and preventing foreign matter from entering them, and an image pickup device 90 for inputting image information are sequentially disposed, and the image pickup device 90 ) Includes a CCD sensor or a CMOS sensor.

Here, the second lens 20 and the third lens 30 are arranged to be spaced apart from each other at a predetermined interval with the diaphragm 70 interposed therebetween, and the fourth lens 40 and the fifth lens 50 are It is configured to correct the chromatic aberration of the junction part by making it abutting so as to make surface contact, and by adjusting the combination of the first lens 10 to the fourth lens 40 to which the aspherical surface is applied and design variables thereof, the chromatic aberration is reduced. It was configured to be minimized.

As described above, by making the first lens 10 to the fourth lens 40 aspherical, it is configured to improve optical aberration such as spherical aberration correction. In a spherical optical system, a lens corresponding to an array of lenses was used as an expensive lens, and it was configured to be made in a low-cost lens configuration.

The optical system according to the present invention with such a configuration reduces the existing total length (TTL: Total Top Length or Total Track Length) to 4.64mm, while satisfying the following conditions, aperture ratio F/2.5, field of view (field of view) 151.6 It is designed to form a degree.

[Condition 1]

1.0 ≤ B/f ≤ 2.0

Here, the focal length of the entire lens system is denoted by f, and the back focal length from the ninth surface (R9) to the focal point of the fifth lens is denoted by B.

[Condition 2]

3.5 ≤ T/f ≤ 7.0

Here, the distance from the first first lens 10 to the last fifth lens 50 of the optical system is referred to as the optical electric length T, and the focal length of the entire lens system is referred to as f.

[Condition 3]

Xo1-Xa1 <0 [Second surface (R4) of second aspherical lens]

Xo2-Xa2 <0 [First surface (R5) of aspherical third lens]

Xo3-Xa3> 0 [Second surface (R6) of aspherical third lens]

Here, when R4, which is a convex surface of the second lens 20, is an aspherical surface, a sag of the reference spherical surface is referred to as Xo1, and a sag due to an aspherical surface is referred to as Xa1.

When R5, which is a concave surface of the third lens 30, is an aspherical surface, a sag of the reference spherical surface is referred to as Xo2, and a sag due to an aspherical surface is referred to as Xa2.

When R6, which is the convex surface of the third lens 30, is an aspherical surface, the sag of the reference spherical surface is referred to as Xo3, and the sag due to the aspherical surface is referred to as Xa3. (However, the dimensions of each unit are absolute. The value is satisfied, and the numerical values after calculation satisfy the real value.)

[Condition 4]

1.49≤n≤1.90, 35≤v≤85 [first lens]

1.54≤n≤1.95, 35≤v≤85 [Second Lens]

1.49≤n≤1.90, 35≤v≤85 [third lens]

1.60≤n≤1.90, 40≤v≤70 [Fourth Lens]

1.49≤n≤1.95, 40≤v≤70 [Fifth Lens]

Here, n is the refractive index of the lens, and v is the dispersion factor of the lens.

Next, with reference to FIG. 2, only a configuration different from that of FIG. 1 will be described.

In the optical system of the present invention, the fifth lens 50 has a concave surface R8 on the object side and a negative [(-)Power] magnification lens having a convex surface R9 on the image side. There will be a difference.

The optical system according to the present invention with this configuration reduces the existing total length (TTL: Total Top Length or Total Track Length) to 4.54mm while satisfying the following conditions, aperture ratio F/2.5, field of view (angle of view) 141.1 It is designed to form a degree.

[Condition 1]

1.0 ≤ B/f ≤ 2.0

[Condition 2]

3.5 ≤ T/f ≤ 7.0

[Condition 4]

1.49≤n≤1.90, 35≤v≤85 [first lens]

1.54≤n≤1.95, 35≤v≤85 [Second Lens]

1.49≤n≤1.90, 35≤v≤85 [third lens]

1.60≤n≤1.90, 40≤v≤70 [Fourth Lens]

1.49≤n≤1.95, 40≤v≤70 [Fifth Lens]

Here, n is the refractive index of the lens, and v is the dispersion factor of the lens.

Next, with reference to FIG. 3, only a configuration different from that of FIG. 1 will be described.

In the optical system of the present invention, the fifth lens 50 differs from FIG. 1 in that it is a lens having a concave surface R8 on an object side and a convex surface R9 on an image side.

The optical system according to the present invention with such a configuration reduces the existing total length (TTL: Total Top Length or Total Track Length) to 4.51mm while satisfying the following conditions, aperture ratio F/2.5, field of view (field of view) 151.6 It is designed to form a degree.

[Condition 1]

1.0 ≤ B/f ≤ 2.0

[Condition 2]

3.5 ≤ T/f ≤ 7.0

[Condition 4]

1.49≤n≤1.90, 35≤v≤85 [first lens]

1.54≤n≤1.95, 35≤v≤85 [Second Lens]

1.49≤n≤1.90, 35≤v≤85 [third lens]

1.54≤n≤1.90, 40≤v≤70 [Fourth Lens]

1.49≤n≤1.95, 40≤v≤70 [Fifth Lens]

Here, n is the refractive index of the lens, and v is the dispersion factor of the lens.

Next, with reference to FIG. 4, only a configuration different from that of FIG. 1 will be described.

In the optical system of the present invention, the fifth lens 50 is a negative [(-)Power] magnification lens having a concave surface R8 on the object side and a concave surface R9 on the image side. There will be a difference.

The optical system according to the present invention with this configuration reduces the existing total length (TTL: Total Top Length or Total Track Length) to 4.90mm while satisfying the following conditions, aperture ratio F/2.5, field of view (field of view) 151.6 It is designed to form a degree.

[Condition 1]

1.0 ≤ B/f ≤ 2.0

[Condition 2]

4.0 ≤ T/f ≤ 7.0

[Condition 4]

1.49≤n≤1.90, 35≤v≤85 [first lens]

1.54≤n≤1.95, 18≤v≤30 [Second Lens]

1.49≤n≤1.90, 35≤v≤85 [third lens]

1.54≤n≤1.90, 40≤v≤70 [Fourth Lens]

1.49≤n≤1.95, 40≤v≤70 [Fifth Lens]

Here, n is the refractive index of the lens, and v is the dispersion factor of the lens.

Next, with reference to FIG. 5, only a configuration different from that of FIG. 1 will be described.

In the optical system of the present invention, the fifth lens 50 is a negative [(-)Power] magnification lens having a concave surface R8 on the object side and a convex surface R9 on the image side. There will be a difference.

The optical system according to the present invention with such a configuration reduces the existing total length (TTL: Total Top Length or Total Track Length) to 5.03mm, while satisfying the following conditions, aperture ratio F/2.5, field of view (field of view) 120.9 It is designed to form a degree.

[Condition 1]

1.0 ≤ B/f ≤ 2.0

[Condition 2]

4.0 ≤ T/f ≤ 7.0

[Condition 4]

1.49≤n≤1.90, 35≤v≤85 [first lens]

1.54≤n≤1.95, 18≤v≤30 [Second Lens]

1.49≤n≤1.90, 35≤v≤85 [third lens]

1.54≤n≤1.90, 40≤v≤70 [Fourth Lens]

1.49≤n≤1.95, 40≤v≤70 [Fifth Lens]

Here, n is the refractive index of the lens, and v is the dispersion factor of the lens.

Next, with reference to FIG. 6, only the configuration different from that of FIG. 1 will be described.

In the optical system of the present invention, the fifth lens 50 is a negative [(-)Power] magnification lens having a concave surface R8 on the object side and a convex surface R9 on the image side. There will be a difference.

The optical system according to the present invention with such a configuration reduces the existing total length (TTL: Total Top Length or Total Track Length) to 4.15mm, while satisfying the following conditions, aperture ratio F/2.5, field of view (field of view) 141.9 It is designed to form a degree.

[Condition 1]

1.0 ≤ B/f ≤ 2.0

[Condition 2]

3.5 ≤ T/f ≤ 7.0

[Condition 4]

1.49≤n≤1.90, 35≤v≤85 [first lens]

1.54≤n≤1.95, 18≤v≤30 [Second Lens]

1.49≤n≤1.90, 35≤v≤85 [third lens]

1.54≤n≤1.90, 40≤v≤70 [Fourth Lens]

1.49≤n≤1.95, 18≤v≤30 [Fifth Lens]

Here, n is the refractive index of the lens, and v is the dispersion factor of the lens.

Next, the operation of the optical system implemented to satisfy Conditional Equations 1 to 4 will be described.

7 is an optical system for a wide-angle camera according to the present invention, in the case where the curvature on the optical axis of the reference sphere in the spherical surface is C (=1/R) and the height in the optics is Y, the sag Xa and the spherical surface in the aspherical surface As a graph showing the sag Xo in, when comparing the sag Xa in the aspherical lens and the sag Xo in the spherical lens, the following equations 1 (in the case of a spherical lens) and equation 2 (in the case of an aspherical lens) It can be expressed as

[Equation 1]

[Equation 2]

Here, C is the curvature (C=1/R; R is the radius of the lens), Y is the height, K is the conic constant, and AD/AE/AF/AG is the aspheric coefficient, respectively.

When the above conditions 1 and 2 are satisfied through this equation, the optical system can reduce the existing optical electric field, forming an aperture ratio (f/dl) F/2.5, and a field of view (angle of view) of 160 degrees.

Tables 1 and 2 below show data of an optical system according to an embodiment and another embodiment of the present invention, and show the radius of curvature of the lens, the center spacing, the refractive index of the lens, and the dispersion coefficient of the lens.

Lens surface Radius of curvature (r) Spacing(d) Refractive index (n) Dispersion (v) Remark 1st side (R1) 11.7703 0.1405 1.5450 56.0000 2nd side (R2) 0.6321 0.4840 3rd side (R3) -1.9383 0.4003 1.545 56.000 4th side (R4) -1.3870 0.1721 . 0.3336 iris Fifth side (R5) 2.1385 0.7725 1.5450 56.0000 Side 6 (R6) -1.0499 0.0306 Side 7 (R7) 8.6205 0.7409 1.5890 61.3000 Page 8 (R8) -1.1237 0.1405 1.6610 20.3000 Junction Side 9 (R9) 22.4309 0.1053 . 0.1053 1.5170 64.2000 IR-Filter or CCF 0.8252 0.1756 1.5170 64.2000 Window glass 0.2163 Image pickup device

Here, each of the data is a value normalized to an effective focal length (EFL) of 1.0 mm.

K = 0.0, AD = -0.2684647E-1, AE = 0.1441121E-2, AF =, AG = on the first side (R1), K = 0.0, AD = -0.8938509E- on the second side (R6) 1, AE = 0.6029767, AF =, AG = -1.174117. K = 0.0 on the fourth side (R4), AD = 0.2352090E-1, AE = -0.5123460E-1, AF = 0, and on the fifth side (R5) K = 0.0, AD = 0.6853965 E-2, AE = -0.2126628E-1, AF =, AG = -0.2661255E-1.

K = 0.0, AD = 0.1875134, AE =, AF = 0.7075416E-1, AG = on the 6th side (R6), K = 0.0, AD = -0.2584671E-1, AE = on the 9th side (R9) 0.7963374E-1, AF =, AG = 0.9746458E-2.

Lens surface Radius of curvature interval Refractive index Dispersion rate Remark First page 10.5859 0.1263 1.545 56.0 Page 2 0.5685 0.4391 Page 3 -1.6706 0.36 1.545 56.0 Page 4 -1.1495 0.0963 . . . iris . . . Page 5 2.3496 0.5369 1.545 56.0 Page 6 -1.2285 0.6 Page 7 2.8107 0.0158 1.545 56.0 Page 8 -1.0106 0.7264 1.923 20.9 Junction Page 9 -4.3923 0.1263 Junction . 0.1579 IR-Filter or CCF . 0.0947 . 0.6316 0.1579 Window glass 0.5964 Image pickup device

Here, each of the data is a value normalized to an effective focal length (EFL) of 1.0 mm.

K = 0.0 on the fourth side (R4), AD = -0.1047435, AE =0.2757621E-01, AF = 0.1207728E-01, AG = -0.2256242E-02, and K = 0.0 on the fifth side (R5), AD = -0.9121626E-01, AE =, AF = 0.4954857, AG = -8.459527. K = 0.0, AD = 0.3163941E-01, AE = 0.3859544E-01, AF = 0, AG = -2.945129 on the ninth side (R9).

Lens surface Radius of curvature interval Refractive index Dispersion rate Remark First page 11.4267 0.1346 1.5450 56.0000 Page 2 0.6136 0.4741 Page 3 -1.8033 0.3886 1.545 56.000 Page 4 -1.2408 0.1312 0.3511 1.5170 64.2000 iris Page 5 1.9908 0.7159 1.5450 56.0000 Page 6 -1.3772 0.0119 Page 7 3.5930 0.7841 1.5450 56.0000 Page 8 -1.0227 0.1364 1.6610 20.3000 Junction Page 9 -12.2005 0.1023 . 0.1023 1.5170 64.2000 IR-Filter or CCF 0.8352 0.1704 1.5170 64.2000 Window glass 0.1742 Image pickup device

Here, each of the data is a value normalized to an effective focal length (EFL) of 1.0 mm.

K = 0.0 of the first side (R1), AD = -0.8328104E-1, AE = 0.1881768E-1, AF =0.7073156E-2, AG = -0.1134077E-2, and the K of the second side (R2) = 0.0, AD = -0.7252557E-1, AE =, AF = 0.2091852, AG = 4.252094.

K = 0.0, AD = 0.2515633E-1, AE = 0.2633707E-1, AF = 0, AG = -1.480338 on the fourth side (R4), K = 0.0, AD = 0.8038891E on the fifth side (R5) -1, AE = -0.114033, AF =, AG = -0.2235714E-1.

K = 0.0, AD = 0.5586071E-1, AE =, AF = -0.1106434, AG = on the 6th side (R6), K = 0.0, AD = -0.6619898E-2, AE on the 7th side (R7) = -0.1108249, AF =, AG = -0.1188810.

K = 0.0, AD = -0.1629275, AE = 0.2592241, AF =, AG = on the 8th side (R8), K = 0.0, AD = 0.6178502E-1, AE = 0.3862337E- on the 7th side (R9) 1, AF =, AG = -0.4612875E-1.

Lens surface Radius of curvature interval Refractive index Dispersion rate Remark First page 12.2860 0.1466 1.5450 56.0000 Page 2 0.6597 0.4975 Page 3 -2.1855 0.4178 1.661 20.300 Page 4 -2.0913 0.2996 . 0.1599 iris Page 5 2.2902 0.8030 1.5450 56.0000 Page 6 -1.0996 0.0678 Page 7 10.2643 0.7734 1.6970 55.5000 Page 8 -1.1729 0.1466 1.6610 20.3000 Junction Page 9 34.4183 0.1100 . 0.1100 1.5170 64.2000 IR-Filter or CCF 0.9896 0.1833 1.5170 64.2000 Window glass 0.1980 Image pickup device

Here, each of the data is a value normalized to an effective focal length (EFL) of 1.0 mm.

K = 0.0 on the first side (R1), AD = -0.8713041E-2, AE = 0.4185519E2, AF =\, AG =, and on the second side (R2) K = 0.0, AD = 0.5927543E-2, AE = 0.8560820E-2, AF =, AG = -0.8254742E-1.

K = 0.0, AD = -0.3015675E-2, AE =, AF = -0.3466188E-1, AG = on the third side (R3), and K = 0.0, AD = 0.2648284E- on the fourth side (R4) 1, AE = 0.2854105E-1, AF =, AG = 0.1523770.

K = 0.0 on the fifth side (R5), AD = -0.5035000E-1, AE = 0.3608733E-1, AF = 0.1093491E-1, AG = -0.4429469, and K = 0.0 on the sixth side (R6), AD = 0.1109702, AE = 0.4495952E-1, AF =, AG =.

K = 0.0, AD = 0.1905080E-1, AE = 0.6398240E-1, AF =, AG = 0.1821694E-1 on the ninth side (R9).

Lens surface Radius of curvature interval Refractive index Dispersion rate Remark First page 12.3627 0.1475 1.5450 56.0000 Page 2 0.6639 0.4401 Page 3 -12.8397 0.4207 1.661 20.300 Page 4 -15.0508 0.1457 . 0.5827 iris Page 5 2.1449 0.7008 1.5450 56.0000 Page 6 -1.4394 0.0148 Page 7 1.9299 0.8483 1.5450 56.0000 Page 8 -1.1802 0.1475 1.1923 20.9000 Junction Page 9 -5.1295 0.0369 . 0.1106 1.5170 64.2000 IR-Filter or CCF . 1.0511 0.1844 1.5170 64.2000 Window glass 0.1957 Image pickup device

Here, each of the data is a value normalized to an effective focal length (EFL) of 1.0 mm.

K = 0.0 on the first side (R1), AD = -0.1247480, AE = 0.4402475E-1, AF =, AG =, and on the second side (R2) K = 0.0, AD = -0.5726782E-1, AE =, AF = 0.1672325 and AG = -2.093444.

K = 0.0, AD = 0.5975985E-3, AE =, AF = -0.1190689, AG = on the third side (R3), K = 0.0, AD = -0.3741641E-1, AE on the fourth side (R4) = -0.7265768E-1, AF =, AG = -0.2450018.

K = 0.0, AD = 0.1696911E-1, AE =, AF = 0.1093491E-1, AG = on the fifth side (R5), K = 0.0, AD = 0.5683688E-1 on the sixth side (R6), AE = 0.4495952E-1, AF =, AG = 0.6431474E-2.

K = 0.0, AD = 0.1749160E-2, AE = 0.6138034E-2, AF =, AG = -0.2761608E-2 on the eighth side (R8).

Lens surface Radius of curvature interval Refractive index Dispersion rate Remark First page 14.4514 0.1725 1.5450 56.0000 Page 2 0.7502 0.3950 Page 3 -5.7081 0.4311 1.661 20.300 Page 4 -2.9144 0.0517 . 0.0216 iris Page 5 -2.0004 0.7071 1.5450 56.0000 Page 6 -0.8709 0.0194 Page 7 1.3193 0.8623 1.5450 56.0000 Page 8 -1.0520 0.0086 Junction Page 9 -1.0563 0.1725 1.6610 20.3000 Page 10 -21.8582 0.0647 . 0.1293 1.5170 64.2000 IR-Filter or CCF . 0.6898 . 0.2156 1.5170 64.2000 Window glass 0.2109 Image pickup device

Here, each of the data is a value normalized to an effective focal length (EFL) of 1.0 mm.

K = 0.0, AD = -0.6445114e-1, AE = 0.2367988e-1, AF =, AG = on the first side (R1), K = 0.0, AD = 0.1430698e-1 on the second side (R2) , AE = -0.5755946e-2, AF =, AG = 0.2833427.

K = 0.0 on the third side (R3), AD = -0.5755979e-1, AE =, AF = -0.1670584, AG =, and on the fourth side (R4) K = 0.0, AD = 0.7764539, AE = -0.7386457 , AF =, AG = 35.95757.

K = 0.0, AD = 0.6522087, AE = -2.174956, AF =, AG = 25.85953 on the 6th side (R6), K = 0.0, AD = -0.1216875, AE =, AF =-on the 7th side (R7) 0.4981387, AG =

K = 0.0, AD = -0.7770388e-1, AE = 0.2083790e-1, AF =, AG = 0.8240250e-3 on the 8th side (R8), K = 0.0, AD = on the 9th side (R9) 0.3813756e-1, AE =, AF = 0.8998644e-1, AG =.

The present invention can realize miniaturization of the optical system by reducing the overall length, and at the same time, not only reducing the manufacturing cost by arranging the entire lens as an aspherical lens, but also securing an ambient light ratio of 90% or more, thereby reducing the brightness of the center and surroundings of the lens. It is possible to solve the difference to the object so that a clear image of the object can be obtained, and it can be applied to both CCD and CMOS cameras.

Although the present invention has been described through the above embodiments, the present invention is not limited thereto. The above embodiments may be modified or changed without departing from the spirit and scope of the present invention, and those skilled in the art will recognize that such modifications and changes also belong to the present invention.

Claims (3)

A first lens 10 having a convex surface on the object side and a concave surface on the image side, a second lens 20 having a concave surface R3 on the object side and a convex surface R4 on the image side, and A third lens 30 having a convex surface R5 and a convex surface R6 on the image side, and a fourth lens having a convex surface R7 on the object side and a convex surface R8 on the image side ( 40), disposed in front of the image side of the fifth lens 50 and the fifth lens 50 having a concave surface R8 on the object side and a concave surface R9 on the image side. ), and an IR cutoff filter 60 for removing light from the first lens 10 and an aperture 70 for selectively converging the light from which the infrared region selectively converging light incident from the first lens 10,
The lenses (10, 20, 30, 40, 50) are all aspherical lenses, characterized in that, the optical system for a wide-angle camera.
The method of claim 1,
When the focal length of the entire lens system is f and the rear focal length is B,
An optical system for a wide-angle camera, characterized in that it satisfies a condition of 1.0 ≤ B/f ≤ 2.0.
The method of claim 1,
When T is the distance from the first lens surface to the last lens surface of the optical system and f is the focal length of the entire lens system,
An optical system for a wide-angle camera, characterized in that it satisfies a condition of 3.5 ≤ T/f ≤ 7.0.

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