Image capturing optical lens

Abstract

To provide an image capturing optical lens which offers good optical performance while satisfying design requirements of a large aperture and a wide angle of view.SOLUTION: An image capturing optical lens provided herein comprises, in order from an object side to an image side, a first lens having negative refractive power, a second lens having refractive power, a third lens having negative refractive power, a fourth lens having positive refractive power, a fifth lens having positive refractive power, and a sixth lens having negative refractive power. The image capturing optical lens satisfies the following relationship expressions: n1≥1.70, 5.00≤TTL / f≤6.50, -6.70≤R12 / R11≤-1.80, where n1 represents a refractive index of the first lens, f represents a focal length of the camera optical lens, TTL represents a total optical length of the camera optical lens, R11 represents a central curvature radius of an object-side surface of the sixth lens, and R12 represents a central curvature radius of an image-side surface of the sixth lens.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to the field of optical lenses, and particularly to an optical lens for a camera applicable to portable terminal devices such as smartphones and digital cameras, and imaging devices such as monitors, PC lenses, in-vehicle lenses, and drones.

Background Art

[0002] In recent years, with the rise of various smart devices, the demand for miniaturized optical lenses for cameras has increased. Moreover, due to the miniaturization of the pixel size of photosensitive elements, combined with the current development trends of high functionality, thinness, and portability of electronic products, miniaturized imaging optical lenses with good image quality have become the mainstream in the current market. In order to obtain better image quality, the multi-chip integration of lenses is progressing. Also, with the development of technology and the diversification of user needs, the pixel size of photosensitive elements has been reduced, and the requirements for the image quality of the system have continued to improve. Therefore, a six-element lens structure has gradually emerged in lens design. An imaging optical lens with excellent optical performance, a large aperture, and an ultra-wide angle is desired.

Summary of the Invention

[0003] In view of the above problems, an object of the present invention is to provide an imaging optical lens having good optical performance while satisfying the design requirements of a large aperture and an ultra-wide angle.

[0004] To solve the above technical problems, an embodiment of the present invention provides an imaging optical lens. The imaging optical lens includes, in order from the object side to the image side, a first lens having a negative refractive power, a second lens having a refractive power, a third lens having a negative refractive power, a fourth lens having a positive refractive power, a fifth lens having a positive refractive power, and a sixth lens having a negative refractive power. The first lens is made of a glass material, and the fourth lens is made of a glass material. Let the refractive index of the first lens be n1, the focal length of the camera optical lens be f, the overall optical length of the camera optical lens be TTL, the radius of curvature of the center of the object-side surface of the sixth lens be R11, the radius of curvature of the center of the image-side surface of the sixth lens be R12, and the following relational expressions are satisfied. n1≥1.70 5.00≤TTL / f≤6.50 -6.70≤R12 / R11≤-1.80

[0005] Preferably, let the Abbe number of the fourth lens be v4, and the following relational expression is satisfied. 60.00≤v4≤91.00

[0006] Preferably, let the on-axis thickness of the second lens be d3, the on-axis thickness of the third lens be d5, and the following relational expression is satisfied. 1.68≤d5 / d3≤6.00

[0007] Preferably, let the focal length of the fifth lens be f5, and the following relational expression is satisfied. 1.00≤f5 / f≤2.10

[0008] Preferably, let the on-axis distance from the image-side surface of the sixth lens to the image plane be BF, and the following relational expression is satisfied. 0.20≤BF / TTL≤0.35

[0009] Preferably, the object side surface of the first lens is convex at the paraxial position, the image side surface of the first lens is concave at the paraxial position, the focal length of the first lens is f1, the central radius of curvature of the object side surface of the first lens is R1, the central radius of curvature of the image side surface of the first lens is R2, the on-axis thickness of the first lens is d1, and the following relational expressions are satisfied. -3.89 ≦ f1 / f ≦ -1.01 0.82 ≦ (R1 + R2) / (R1 - R2) ≦ 3.22 0.02 ≦ d1 / TTL ≦ 0.34

[0010] Preferably, the object side surface of the second lens is concave at the paraxial position, the image side surface of the second lens is convex at the paraxial position, the focal length of the second lens is f2, the central radius of curvature of the object side surface of the second lens is R3, the central radius of curvature of the image side surface of the second lens is R4, the on-axis thickness of the second lens is d3, and the following relational expressions are satisfied. -95.3 ≦ f2 / f ≦ 37.04 -25.35 ≦ (R3 + R4) / (R3 - R4) ≦ 34.72 0.01 ≦ d3 / TTL ≦ 0.13

[0011] Preferably, the object side surface of the third lens is concave at the paraxial position, the image side surface of the third lens is convex at the paraxial position, the focal length of the third lens is f3, the central radius of curvature of the object side surface of the third lens is R5, the central radius of curvature of the image side surface of the third lens is R6, the on-axis thickness of the third lens is d5, and the following relational expressions are satisfied. -1980 ≦ f3 / f ≦ -8.53 -16.53 ≦ (R5 + R6) / (R5 - R6) ≦ -3.57 0.07 ≦ d5 / TTL ≦ 0.28

[0012] Preferably, the object side surface of the fourth lens is convex at the paraxial position, the image side surface of the fourth lens is convex at the paraxial position, the focal length of the fourth lens is f4, the central radius of curvature of the object side surface of the fourth lens is R7, the central radius of curvature of the image side surface of the fourth lens is R8, the on-axis thickness of the fourth lens is d7, and the following relational expressions are satisfied. 0.78 ≦ f4 / f ≦ 3.29 -0.65 ≦ (R7 + R8) / (R7 - R8) ≦ 0.06 0.03 ≦ d7 / TTL ≦ 0.22

[0013] Preferably, the first lens is made of a glass material, and the fourth lens is made of a glass material.

[0014] The beneficial effects of the present invention are that the camera optical lens according to the present invention has excellent optical characteristics, has a large aperture and an ultra-wide angle, and is particularly suitable for a mobile phone camera lens assembly, a WEB camera lens, and a day / night co-focus vehicle lens having an operating wavelength band in the RGB+IR range, which are composed of camera elements such as high pixel number CCDs and CMOSs.

Brief Description of the Drawings

[0015] To more clearly explain the technical means in the embodiments of the present invention, the drawings necessary for explaining the embodiments will be briefly described below. Note that the drawings in the following description are only some embodiments of the present invention. Those skilled in the art can obtain other drawings based on these drawings without performing creative work.

[0016]

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Embodiments for Carrying Out the Invention

[0017] In order to make the object, technical means, and advantages of the present invention clearer, various embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings. It should be understood by those skilled in the art that in various embodiments of the present invention, many technical details have been proposed to enable readers to better understand the present invention. However, it is claimed that the technical solution of the present invention can be realized without these technical details and various modifications and changes based on the following embodiments.

[0018] (First Embodiment) Referring to the accompanying drawings, the present invention provides an imaging optical lens 10. FIG. 1 shows the imaging optical lens 10 according to the first embodiment of the present invention, and this imaging optical lens 10 includes six lenses. Specifically, this imaging optical lens 10 includes, in order from the object side to the image side, a first lens L1, a second lens L2, a third lens L3, a diaphragm S1, a fourth lens L4, a fifth lens L5, and a sixth lens L6. Also, an optical element such as an optical filter (Filter) GF may be provided between the sixth lens L6 and the image plane Si.

[0019] In this embodiment, the first lens L1 is made of a glass material, the second lens L2 is made of a plastic material, the third lens L3 is made of a plastic material, the fourth lens L4 is made of a glass material, the fifth lens L5 is made of a plastic material, and the sixth lens L6 is made of a plastic material. In any other embodiment, each lens may be made of other materials.

[0020] Also, in this embodiment, the refractive index of the first lens L1 is defined as n1, and the following relational expression is satisfied: n1 ≥ 1.70. Thereby, the refractive index of the first lens is defined. The first lens is preferably made of a high refractive index material, and within the range of the conditional expression, it is advantageous for miniaturizing the front aperture diameter and improving the imaging quality.

[0021] Also, in this embodiment, the focal length of the imaging optical lens 10 is defined as f, the overall optical length of the imaging optical lens 10 is defined as TTL, and the following relational expression is satisfied: 5.00 ≤ TTL / f ≤ 6.50. Thereby, the ratio of the overall system length to the focal length is defined, and within the range of the conditional expression, it is possible to control the overall optical length to be short, facilitating miniaturization, and to balance the field curvature of the system so that the field curvature offset of the central field of view is less than 0.02 mm.

[0022] Also, in this embodiment, the central radius of curvature of the object side surface of the sixth lens L6 is defined as R11, the central radius of curvature of the image side surface of the sixth lens L6 is defined as R12, and the following relational expression is satisfied: -6.70 ≤ R12 / R11 ≤ -1.80. Thereby, the shape of the sixth lens is defined, and within the range of the conditional expression, the refraction of light rays passing through the lens can be alleviated, and good imaging quality and low sensitivity can be obtained.

[0023] Also, in this embodiment, the Abbe number of the fourth lens L4 is defined as v4, and the following relational expression is satisfied: 60.00 ≤ v4 ≤ 91.00. Thereby, the Abbe number of the fourth lens L4 is defined, and within the range of the conditional expression, the material characteristics can be effectively distributed, the aberration can be effectively improved, and the imaging quality can be improved.

[0024] In addition, in the present embodiment, the on-axis thickness of the second lens L2 is defined as d3, the on-axis thickness of the third lens L3 is defined as d5, and the following relational expression is satisfied: 1.68 ≤ d5 / d3 ≤ 6.00. Thereby, the ratio of the center thickness of the third lens to the center thickness of the second lens is defined, and within the range of the conditional expression, by appropriately distributing the center thicknesses between the lenses, the assembly difficulty in the actual manufacturing process can be reduced, and the yield can be improved.

[0025] In addition, in the present embodiment, the focal length of the imaging optical lens 10 is defined as f, the focal length of the fifth lens L5 is defined as f5, and the following relational expression is satisfied: 1.00 ≤ f5 / f ≤ 2.10. Thereby, within the range of the conditional expression, by controlling the focal length value of the fifth lens and appropriately distributing the focal lengths, it is advantageous for temperature control, and good temperature performance can be realized.

[0026] In addition, in the present embodiment, the on-axis distance from the image side surface of the sixth lens L6 to the image plane Si is defined as BF, and the following relational expression is satisfied: 0.20 ≤ BF / TTL ≤ 0.35. Thereby, within the range of the conditional expression, since the back focus becomes longer in realizing miniaturization, it is advantageous for the assembly of the module.

[0027] In addition, in the present embodiment, the object side surface of the first lens L1 is convex at the paraxial position, the image side surface is concave at the paraxial position, and the first lens L1 has a negative refractive power. In any other embodiment, the object side surface and the image side surface of the first lens L1 may have other convex-concave distributions.

[0028] In addition, the focal length of the photographing optical lens 10 is defined as f, the focal length of the first lens L1 is defined as f1, and the following relational expression is satisfied: -3.89 ≤ f1 / f ≤ -1.01. Thereby, the ratio of the negative refractive power of the first lens L1 to the overall focal length is defined, and within the range of the conditional expression, the first lens has an appropriate negative refractive power, which is advantageous for reducing the system aberration and thinning and widening the lens. Further, preferably, -2.43 ≤ f1 / f ≤ -1.26 is satisfied.

[0029] Define the radius of curvature of the center of the object side surface of the first lens L1 as R1, and the radius of curvature of the center of the image side surface of the first lens L1 as R2, satisfying the following relational expression: 0.82 ≤ (R1 + R2) / (R1 - R2) ≤ 3.22. Thereby, the shape of the first lens can be reasonably controlled, and effective correction of system spherical aberration can be achieved. Also preferably, 1.32 ≤ (R1 + R2) / (R1 - R2) ≤ 2.58 is satisfied.

[0030] Define the thickness on the optical axis of the first lens L1 as d1, and the total optical length of the imaging optical lens 10 as TTL, satisfying the following relational expression: 0.02 ≤ d1 / TTL ≤ 0.34. Thereby, it is advantageous for miniaturization within the range of the conditional expression. Also preferably, 0.03 ≤ d1 / TTL ≤ 0.27 is satisfied.

[0031] Also, in the present embodiment, the object side surface of the second lens L2 is concave in the paraxial region, and the image side surface is convex in the paraxial region, and the second lens L2 has a positive or negative refractive power. Note that in any other embodiment, the object side surface and the image side surface of the second lens L2 may have other concavo-convex distributions.

[0032] Define the focal length of the imaging optical lens 10 as f, and the focal length of the second lens L2 as f2, satisfying the following relational expression: -95.3 ≤ f2 / f ≤ 37.04. By controlling the negative focal power of the second lens L2 within an appropriate range, it is advantageous for aberration correction of the optical system. Also preferably, -59.6 ≤ f2 / f ≤ 29.63 is satisfied.

[0033] Define the radius of curvature of the center of the object side surface of the second lens L2 as R3, and the radius of curvature of the center of the image side surface of the second lens L2 as R4, satisfying the following relational expression: -25.35 ≤ (R3 + R4) / (R3 - R4) ≤ 34.72. Thereby, the shape of the second lens L2 is defined, and within the range, with the development of ultra-thin wide-angle, it is advantageous for aberration correction of off-axis field angles, etc. Also preferably, -15.84 ≤ (R3 + R4) / (R3 - R4) ≤ 27.78 is satisfied.

[0034] Let the on-axis thickness of the second lens L2 be d3, and the overall optical length of the imaging optical lens 10 be TTL. The following relational expression is satisfied: 0.01 ≤ d3 / TTL ≤ 0.13. Within the range of the conditional expression, it is advantageous for miniaturization. Also, preferably, 0.02 ≤ d3 / TTL ≤ 0.11 is satisfied.

[0035] In this embodiment, the object-side surface of the third lens L3 is concave in the paraxial region, and the image-side surface is convex in the paraxial region. The third lens L3 has a negative refractive power. In any other arbitrary embodiment, the object-side surface and the image-side surface of the third lens L3 may have other concavo-convex distributions.

[0036] Define the focal length of the imaging optical lens 10 as f, and the focal length of the third lens L3 as f3. The following relational expression is satisfied: -1980 ≤ f3 / f ≤ -8.53. By a reasonable distribution of the focal power, the system can be provided with good imaging quality and low sensitivity. Also, preferably, -1240 ≤ f3 / f ≤ -10.7 is satisfied.

[0037] Let the central radius of curvature of the object-side surface of the third lens L3 be R5, and the central radius of curvature of the image-side surface of the third lens L3 be R6. The following relational expression is satisfied: -16.53 ≤ (R5 + R6) / (R5 - R6) ≤ -3.57. Within the range of the conditional expression, the shape of the third lens L3 can be effectively controlled, the molding of the third lens L3 can be facilitated, and molding defects and stress generation due to the surface curvature of the second lens L5 being too large can be avoided. Also, preferably, -10.33 ≤ (R5 + R6) / (R5 - R6) ≤ -4.46 is satisfied.

[0038] Let the on-axis thickness of the third lens L3 be d5, and the overall optical length of the imaging optical lens 10 be TTL. The following relational expression is satisfied: 0.07 ≤ d5 / TTL ≤ 0.28. Within the range of the conditional expression, it is advantageous for realizing miniaturization. Also, preferably, 0.11 ≤ d5 / TTL ≤ 0.22 is satisfied.

[0039] In addition, in the present embodiment, the object side surface of the fourth lens L4 is convex in the paraxial region, the image side surface is convex in the paraxial region, and the fourth lens L4 has a positive refractive power. In any other arbitrary embodiment, the object side surface and the image side surface of the fourth lens L4 may have other concavo-convex distributions.

[0040] Define the focal length of the imaging optical lens 10 as f, define the focal length of the fourth lens L4 as f4, and satisfy the following relational expression: 0.78 ≤ f4 / f ≤ 3.29. By a reasonable distribution of the focal power, the system can be provided with good imaging quality and low sensitivity. Further, preferably, 1.25 ≤ f4 / f ≤ 2.64 is satisfied.

[0041] Let the radius of curvature at the center of the object side surface of the fourth lens L4 be R7, let the radius of curvature at the center of the image side surface of the fourth lens L4 be R8, and satisfy the following relational expression: -0.65 ≤ (R7 + R8) / (R7 - R8) ≤ 0.06. Thereby, the shape of the fourth lens L4 is defined, and within the range, it is advantageous for aberration correction of the off-axis field angle and the like with the development of ultra-thin type. Further, preferably, -0.41 ≤ (R7 + R8) / (R7 - R8) ≤ 0.05 is satisfied.

[0042] Let the on-axis thickness of the fourth lens L4 be d7, let the overall optical length of the imaging optical lens 10 be TTL, and satisfy the following relational expression: 0.03 ≤ d7 / TTL ≤ 0.22. It is advantageous for miniaturization within the range of the conditional expression. Further, preferably, 0.05 ≤ d7 / TTL ≤ 0.17 is satisfied.

[0043] In addition, in the present embodiment, the object side surface of the fifth lens L5 is convex in the paraxial region, the image side surface is convex in the paraxial region, and the fifth lens L5 has a positive refractive power. In any other arbitrary embodiment, the object side surface and the image side surface of the fifth lens L5 may have other concavo-convex distributions.

[0044] Define the radius of curvature of the object side surface of the fifth lens L5 as R9, the radius of curvature of the image side surface of the fifth lens L5 as R10, and satisfy the following relational expression: 0.31 ≤ (R9 + R10) / (R9 - R10) ≤ 1.11. Thereby, the shape of the fifth lens L5 is defined, and within the range, it is advantageous for aberration correction of off-axis field angles and the like with the development of ultra-thin wide-angle. Also, preferably, 0.50 ≤ (R9 + R10) / (R9 - R10) ≤ 0.89 is satisfied.

[0045] Define the on-axis thickness of the fifth lens L5 as d9, define the overall optical length of the imaging optical lens 10 as TTL, and satisfy the following relational expression: 0.05 ≤ d9 / TTL ≤ 0.21. Thereby, it is advantageous for miniaturization within the range of the conditional expression. Also, preferably, 0.07 ≤ d9 / TTL ≤ 0.17 is satisfied.

[0046] Also, in the present embodiment, the object side surface of the sixth lens L6 is concave in the paraxial region, the image side surface is concave in the paraxial region, and the sixth lens L6 has a negative refractive power. Note that in any other embodiment, the object side surface and the image side surface of the sixth lens L6 may have other concavo-convex distributions.

[0047] Let the focal length of the imaging optical lens 10 be f and the focal length of the sixth lens L6 be f6, and satisfy the following relational expression: -4.10 ≤ f6 / f ≤ -0.69. By a reasonable distribution of the focal power, the system can be given good imaging quality and low sensitivity. Also, preferably, -2.56 ≤ f6 / f ≤ -0.87 is satisfied.

[0048] Let the radius of curvature of the object side surface of the sixth lens L6 be R11, the radius of curvature of the image side surface of the sixth lens L6 be R12, and satisfy the following relational expression: -1.48 ≤ (R11 + R12) / (R11 - R12) ≤ -0.19. Thereby, the shape of the sixth lens L6 is defined, and within the conditional range, it is advantageous for aberration correction of off-axis field angles and the like with the development of ultra-thin wide-angle. Also, preferably, -0.92 ≤ (R11 + R12) / (R11 - R12) ≤ -0.24 is satisfied.

[0049] Let the on-axis thickness of the sixth lens L6 be d11 and the overall optical length of the imaging optical lens 10 be TTL. The following relational expression is satisfied: 0.00 ≦ d11 / TTL ≦ 0.03. Being within the range of the conditional expression is advantageous for miniaturization. Also preferably, 0.01 ≦ d11 / TTL ≦ 0.03 is satisfied.

[0050] Also, in this embodiment, since the aperture value FNO of the imaging optical lens 10 is 2.0 or less, a large aperture is realized, and good imaging performance of the imaging optical lens can be achieved.

[0051] Also, in this embodiment, since the angle of view FOV of the imaging optical lens 10 is 125° or more, an ultra-wide angle is realized, and good imaging performance of the imaging optical lens can be achieved.

[0052] The imaging optical lens 10 has good optical performance and can meet the design requirements of a large aperture and an ultra-wide angle. Depending on the characteristics of this imaging optical lens 10, it is particularly suitable for a mobile phone imaging lens assembly composed of an imaging element such as a high-pixel CCD or CMOS, a WEB imaging lens, and a day / night co-focus in-vehicle lens whose operating band is RGB + IR.

[0053] Hereinafter, the imaging optical lens 10 of the present invention will be described by way of examples. The reference signs described in each example are as follows. Note that the units of the focal length, on-axis distance, central radius of curvature, on-axis thickness, inflection point position, and stop point position are mm.

[0054] TTL: Overall optical length (the on-axis distance from the object side surface of the first lens L1 to the image plane Si), the unit is mm;

[0055] Aperture value FNO: The ratio of the effective focal length of the imaging optical lens to the pupil diameter.

[0056] Preferably, in order to meet the high-quality imaging requirements, an inflection point and / or a stop point may be provided on the object side surface and / or the image side surface of the lens. Also, specific embodiments will be described below.

[0057] Tables 1 and 2 are tables showing the design data of the imaging optical lens 10 according to the first embodiment of the present invention.

[0058] [Table 1]

[0059] Here, the meanings of the respective symbols are as follows. S1: Diaphragm; R: Radius of curvature of the center of the optical surface; R1: Radius of curvature of the center of the object side surface of the first lens L1; R2: Radius of curvature of the center of the image side surface of the first lens L1; R3: Radius of curvature of the center of the object side surface of the second lens L2; R4: Radius of curvature of the center of the image side surface of the second lens L2; R5: Radius of curvature of the center of the object side surface of the third lens L3; R6: Radius of curvature of the center of the image side surface of the third lens L3; R7: Radius of curvature of the center of the object side surface of the fourth lens L4; R8: Radius of curvature of the center of the image side surface of the fourth lens L4; R9: Radius of curvature of the center of the object side surface of the fifth lens L5; R10: Radius of curvature of the center of the image side surface of the fifth lens L5; R11: Radius of curvature of the center of the object side surface of the sixth lens L6; R12: Radius of curvature of the center of the image side surface of the sixth lens L6; R13: Radius of curvature of the center of the object side surface of the optical filter GF; R14: Radius of curvature of the center of the image side surface of the optical filter GF; d: Axial thickness of the lens and axial distance between the lenses; d0: Axial distance from the diaphragm S1 to the object side surface of the first lens L1; d1: Axial thickness of the first lens L1; d2: Axial distance from the image side surface of the first lens L1 to the object side surface of the second lens L2; d3: Axial thickness of the second lens L2; d4: Axial distance from the image side surface of the second lens L2 to the object side surface of the third lens L3; d5: Axial thickness of the third lens L3; d6: Axial distance from the image side surface of the third lens L3 to the object side surface of the fourth lens L4; d7: Axial thickness of the fourth lens L4; d8: Axial distance from the image side surface of the fourth lens L4 to the object side surface of the fifth lens L5; d9: Axial thickness of the fifth lens L5; d10: Axial distance from the image side surface of the fifth lens L5 to the object side surface of the sixth lens L6; d11: Axial thickness of the sixth lens L6; d12: Axial distance from the image side surface of the sixth lens L6 to the object side surface of the optical filter GF; d13: Axial thickness of the optical filter GF; d14: Axial distance from the image side surface of the optical filter GF to the image plane Si; BF: Axial distance from the image side surface of the sixth lens L6 to the image plane Si; nd: Refractive index of the d-line (the d-line is green light with a wavelength of 550 nm); nd1: Refractive index of the d-line of the first lens L1; nd2: Refractive index of the d-line of the second lens L2; nd3: Refractive index of the d-line of the third lens L3; nd4: Refractive index of the d-line of the fourth lens L4; nd5: Refractive index of the d-line of the fifth lens L5; nd6: Refractive index of the d-line of the sixth lens L6; ndg: Refractive index of the d-line of the optical filter GF; vd: 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; vg: Abbe number of the optical filter GF.

[0060] Table 2 is a table showing the aspherical data of each lens of the imaging optical lens 10 according to the first embodiment of the present invention.

[0061] [Table 2]

[0062] For the aspherical surfaces of the respective lens surfaces, for the sake of convenience, the aspherical surface represented by the following formula (1) is used. However, the present invention is not limited to the polynomial form of the aspherical surface represented by this formula (1).

[0063] [Formula 1] z=(cr 2 ) / {1+[1-(k + 1)(c 2 r 2 )] 1 / 2}+A4r 4 +A6r 6 +A8r 8 +A10r 10 +A12r 12 +A14r 14 +A16r 16 +A18r 18 +A20r 20 (1)

[0064] Here, k is the conic coefficient, A4, A6, A8, A10, A12, A14, A16, A18, A20 are the aspherical coefficients, c is the curvature at the center of the optical surface, r is the perpendicular distance between the point on the aspherical curve and the optical axis, and z is the aspherical depth (the perpendicular distance between the point where the distance from the optical axis is r on the aspherical surface and the tangent plane that touches the vertex on the aspherical optical axis).

[0065] Tables 3 and 4 are tables showing the design data of the inflection points and stationary points of each lens in the imaging optical lens 10 according to the first embodiment of the present invention. Here, P1R1 and P1R2 represent the object side surface and the image side surface of the first lens L1, respectively, P2R1 and P2R2 represent the object side surface and the image side surface of the second lens L2, respectively, P3R1 and P3R2 represent the object side surface and the image side surface of the third lens L3, respectively, P4R1 and P4R2 represent the object side surface and the image side surface of the fourth lens L4, respectively, P5R1 and P5R2 represent the object side surface and the image side surface of the fifth lens L5, respectively, and P6R1 and P6R2 represent the object side surface and the image side surface of the sixth lens L6, respectively. In addition, the data corresponding to the "inflection point position" column is the vertical distance from the inflection point set on each lens surface to the optical axis of the imaging optical lens 10. The data corresponding to the "stationary point position" column is the vertical distance from the stationary point set on each lens surface to the optical axis of the imaging optical lens 10.

[0066]

Table 3

[0067]

Table 4

[0068] Figures 2 and 3 are schematic diagrams showing the axial aberration and magnification chromatic aberration after light with wavelengths of 960 nm, 940 nm, 920 nm, 650 nm, 610 nm, 555 nm, 510 nm, 470 nm, and 435 nm passes through the imaging optical lens 10 of the first embodiment. Figure 4 is a schematic diagram showing the field curvature and distortion after light with a wavelength of 555 nm passes through the imaging optical lens 10 of the first embodiment. The field curvature S in Figure 4 is the field curvature in the sagittal direction, and T is the field curvature in the meridional direction.

[0069] Table 29 shown later shows the various numerical values in each example and the values corresponding to the parameters defined by the conditional expressions.

[0070] As shown in Table 29, the first embodiment satisfies each conditional expression.

[0071] In addition, in the present embodiment, the entrance pupil diameter EMPD of the imaging optical lens 10 is 1.163 mm, the full field image height IH is 3.400 mm, and the field of view angle FOV in the diagonal direction is 165.96°. The imaging optical lens 10 satisfies the design requirements of a large aperture and an ultra-wide angle, and the axial and off-axis chromatic aberrations are appropriately corrected, and it has excellent optical characteristics.

[0072] (Second Embodiment) The second embodiment is basically the same as the first embodiment, and since the reference signs represent the same meaning as those in the first embodiment, only the differences will be listed below.

[0073] FIG. 5 is a diagram showing an imaging optical lens 20 according to the second embodiment of the present invention.

[0074] Tables 5 and 6 are tables showing the design data of the imaging optical lens 20 according to the second embodiment of the present invention.

[0075] [Table 5]

[0076] Table 6 is a table showing the aspherical data of each lens in the imaging optical lens 20 according to the second embodiment of the present invention.

[0077] [Table 6]

[0078] Tables 7 and 8 are tables showing the design data of the inflection points and stationary points of each lens in the imaging optical lens 20 according to the second embodiment of the present invention.

[0079] [Table 7]

[0080]

Table 8

[0081] FIG. 6 and FIG. 7 are schematic diagrams showing the axial aberration and magnification chromatic aberration after light of wavelengths 960 nm, 940 nm, 920 nm, 650 nm, 610 nm, 555 nm, 510 nm, 470 nm, and 435 nm has passed through the imaging optical lens 20 of the second embodiment. FIG. 8 is a schematic diagram showing the field curvature and distortion after light of wavelength 555 nm has passed through the imaging optical lens 20 of the second embodiment. The field curvature S in FIG. 8 is the field curvature in the sagittal direction, and T is the field curvature in the meridional direction.

[0082] As shown in Table 29, the second embodiment satisfies each conditional expression.

[0083] Also, in the present embodiment, the entrance pupil diameter EMPD of the imaging optical lens 20 is 1.329 mm, the full field image height IH is 3.400 mm, and the field of view angle FOV in the diagonal direction is 150.85°. The imaging optical lens 20 satisfies the design requirements of a large aperture and an ultra-wide angle, and the axial and off-axis chromatic aberrations are appropriately corrected, and it has excellent optical characteristics.

[0084] (Third Embodiment) The third embodiment is basically the same as the first embodiment, and since the reference signs represent the same meanings as those in the first embodiment, only the differences will be listed below.

[0085] FIG. 9 is a diagram showing an imaging optical lens 30 according to the third embodiment of the present invention.

[0086] Tables 9 and 10 are tables showing the design data of the imaging optical lens 30 according to the third embodiment of the present invention.

[0087]

Table 9

[0088] Table 10 is a table showing the aspherical data of each lens of the imaging optical lens 30 according to the third embodiment of the present invention.

[0089]

Table 10

[0090] Table 11 and Table 12 are tables showing the design data of the inflection points and stationary points of each lens in the imaging optical lens 30 according to the third embodiment of the present invention.

[0091]

Table 11

[0092]

Table 12

[0093] FIG. 10 and FIG. 11 are schematic diagrams showing the axial aberration and chromatic aberration of magnification after light of wavelengths 960 nm, 940 nm, 920 nm, 650 nm, 610 nm, 555 nm, 510 nm, 470 nm, and 435 nm has passed through the imaging optical lens 30 of the third embodiment. FIG. 12 is a schematic diagram showing the field curvature and distortion after light of wavelength 555 nm has passed through the imaging optical lens 30 of the third embodiment. The field curvature S in FIG. 12 is the field curvature in the sagittal direction, and T is the field curvature in the meridional direction.

[0094] As shown in Table 29, the third embodiment satisfies each conditional expression.

[0095] Also, in the present embodiment, the entrance pupil diameter EMPD of the imaging optical lens 30 is 1.435 mm, the full field image height IH is 3.400 mm, and the field angle FOV in the diagonal direction is 126.08°. The imaging optical lens 30 satisfies the design requirements of a large aperture and ultra-wide angle, and the axial and off-axis chromatic aberrations are appropriately corrected, and it has excellent optical characteristics.

[0096] (Fourth Embodiment) The fourth embodiment is basically the same as the first embodiment, and since the reference signs represent the same meanings as those in the first embodiment, only the differences will be listed below.

[0097] FIG. 13 is a diagram showing an imaging optical lens 40 according to the fourth embodiment of the present invention.

[0098] Tables 13 and 14 are tables showing the design data of the imaging optical lens 40 according to the fourth embodiment of the present invention.

[0099] [Table 13]

[0100] Table 14 is a table showing the aspherical data of each lens of the imaging optical lens 40 according to the fourth embodiment of the present invention.

[0101] [Table 14]

[0102] Tables 15 and 16 are tables showing the design data of the inflection points and standing points of each lens in the imaging optical lens 40 according to the fourth embodiment of the present invention.

[0103] [Table 15]

[0104] [Table 16]

[0105] Figures 14 and 15 are schematic diagrams showing the axial aberration and chromatic aberration of magnification after light with wavelengths of 960 nm, 940 nm, 920 nm, 650 nm, 610 nm, 555 nm, 510 nm, 470 nm, and 435 nm has passed through the imaging optical lens 40 of the fourth embodiment. Figure 16 is a schematic diagram showing the field curvature and distortion after light with a wavelength of 555 nm has passed through the imaging optical lens 40 of the fourth embodiment. The field curvature S in Figure 16 is the field curvature in the sagittal direction, and T is the field curvature in the meridional direction.

[0106] As shown in Table 29, the fourth embodiment satisfies each conditional expression.

[0107] Also, in the present embodiment, the entrance pupil diameter EMPD of the imaging optical lens 40 is 1.297 mm, the full field image height IH is 3.400 mm, and the field of view angle FOV in the diagonal direction is 149.20°. The imaging optical lens 40 satisfies the design requirements of a large aperture and ultra-wide angle, and the axial and off-axis chromatic aberrations are appropriately corrected, having excellent optical characteristics.

[0108] (Fifth Embodiment) The fifth embodiment is basically the same as the first embodiment, and since the reference signs represent the same meaning as those in the first embodiment, only the differences will be listed below.

[0109] Figure 17 is a diagram showing the imaging optical lens 50 according to the fifth embodiment of the present invention.

[0110] Tables 17 and 18 are tables showing the design data of the imaging optical lens 50 according to the fifth embodiment of the present invention.

[0111] [Table 17]

[0112] Table 18 is a table showing the aspherical data of each lens of the imaging optical lens 50 according to the fifth embodiment of the present invention.

[0113] [Table 18]

[0114] Tables 19 and 20 are tables showing the design data of the inflection points and stationary points of each lens in the imaging optical lens 50 according to the fifth embodiment of the present invention.

[0115] [Table 19]

[0116] [Table 20]

[0117] FIG. 18 and FIG. 19 are schematic diagrams showing the axial aberration and magnification chromatic aberration after light of wavelengths 960 nm, 940 nm, 920 nm, 650 nm, 610 nm, 555 nm, 510 nm, 470 nm, and 435 nm has passed through the imaging optical lens 50 of the fifth embodiment. FIG. 20 is a schematic diagram showing the field curvature and distortion after light of wavelength 555 nm has passed through the imaging optical lens 50 of the fifth embodiment. The field curvature S in FIG. 20 is the field curvature in the sagittal direction, and T is the field curvature in the meridional direction.

[0118] As shown in Table 29, the fifth embodiment satisfies each conditional expression.

[0119] Also, in the present embodiment, the entrance pupil diameter EMPD of the imaging optical lens 50 is 1.516 mm, the full field image height IH is 3.400 mm, and the field angle FOV in the diagonal direction is 125.52°. The imaging optical lens 50 satisfies the design requirements of a large aperture and an ultra-wide angle, and the axial and off-axis chromatic aberrations are appropriately corrected, and it has excellent optical characteristics.

[0120] (Sixth Embodiment) The sixth embodiment is basically the same as the first embodiment, and since the reference signs represent the same meaning as those in the first embodiment, only the differences will be listed below.

[0121] FIG. 21 is a diagram showing an imaging optical lens 60 according to a sixth embodiment of the present invention.

[0122] Tables 21 and 22 are tables showing design data of the imaging optical lens 60 according to the sixth embodiment of the present invention.

[0123] [Table 21]

[0124] Table 22 is a table showing aspherical data of each lens of the imaging optical lens 60 according to the sixth embodiment of the present invention.

[0125] [Table 22]

[0126] Tables 23 and 24 are tables showing design data of the inflection points and stationary points of each lens in the imaging optical lens 60 according to the sixth embodiment of the present invention.

[0127] [Table 23]

[0128] [Table 24]

[0129] FIGS. 22 and 23 are schematic diagrams showing axial aberration and chromatic aberration of magnification after light of wavelengths 960 nm, 940 nm, 920 nm, 650 nm, 610 nm, 555 nm, 510 nm, 470 nm, and 435 nm has passed through the imaging optical lens 60 of the sixth embodiment. FIG. 24 is a schematic diagram showing field curvature and distortion after light of wavelength 555 nm has passed through the imaging optical lens 60 of the sixth embodiment. The field curvature S in FIG. 24 is the field curvature in the sagittal direction, and T is the field curvature in the meridional direction.

[0130] As shown in Table 29, the sixth embodiment satisfies each conditional expression.

[0131] Also, in this embodiment, the entrance pupil diameter EMPD of the imaging optical lens 60 is 1.138 mm, the full field image height IH is 3.400 mm, and the field of view angle FOV in the diagonal direction is 171.38°. The imaging optical lens 60 satisfies the design requirements of a large aperture and an ultra-wide angle, and the axial and off-axis chromatic aberrations are appropriately corrected, and it has excellent optical characteristics.

[0132] (Comparative Embodiment) The comparative embodiment is basically the same as the first embodiment, and the reference signs represent the same meanings as those in the first embodiment. Therefore, only the differences will be listed below.

[0133] FIG. 25 is a diagram showing an imaging optical lens 70 according to a comparative embodiment of the present invention.

[0134] Tables 25 and 26 are tables showing the design data of the imaging optical lens 70 according to the comparative embodiment of the present invention.

[0135]

Table 25

[0136] Table 26 is a table showing the aspherical data of each lens of the imaging optical lens 70 according to the comparative embodiment of the present invention.

[0137]

Table 26

[0138] Tables 27 and 28 are tables showing the design data of the inflection points and standing points of each lens in the imaging optical lens 70 according to the comparative embodiment of the present invention.

[0139]

Table 27

[0140]

Table 28

[0141] Figures 26 and 27 are schematic diagrams showing the axial aberration and magnification chromatic aberration after light with wavelengths of 960 nm, 940 nm, 920 nm, 650 nm, 610 nm, 555 nm, 510 nm, 470 nm, and 435 nm has passed through the imaging optical lens 70 of the comparative embodiment. Figure 28 is a schematic diagram showing the field curvature and distortion after light with a wavelength of 555 nm has passed through the imaging optical lens 70 of the comparative embodiment. The field curvature S in Figure 28 is the field curvature in the sagittal direction, and T is the field curvature in the meridional direction.

[0142] Hereinafter, Table 29 shows the numerical values corresponding to each conditional expression in the comparative embodiment according to the above conditional expressions. It is clear that the imaging optical lens 70 of the comparative embodiment does not satisfy the conditional expression 5.00 ≦ TTL / f ≦ 6.50 described above.

[0143] Also, in the comparative embodiment, the entrance pupil diameter EMPD of the imaging optical lens 70 is 1.164 mm, the full field image height IH is 3.400 mm, and the field of view angle FOV in the diagonal direction is 160.81°. The imaging optical lens 70 does not meet the design requirements of a large aperture and ultra-wide angle.

[0144]

Table 29

[0145] Each of the above embodiments is a specific embodiment for realizing the present invention, and it can be understood by those skilled in the art that various changes can be made in form and details in practical application without departing from the spirit and scope of the present invention.

Claims

1. 1. An imaging optical lens, comprising: the imaging optical lens is composed of, in order from the object side to the image side, a first lens having negative refractive power, a second lens having refractive power, a third lens having negative refractive power, a fourth lens having positive refractive power, a fifth lens having positive refractive power, and a sixth lens having negative refractive power; Here, the imaging optical lens is characterized in that a refractive index of the first lens is n1, a focal length of the camera optical lens is f, a total optical length of the camera optical lens is TTL, a central radius of curvature of the object-side surface of the sixth lens is R11, and a central radius of curvature of the image-side surface of the sixth lens is R12, and the following relational expression is satisfied. n1≧1.70 5.00≦TTL / f≦6.50 −6.70≦R12 / R11≦−1.80

2. 2. The imaging optical lens according to claim 1, wherein the Abbe number of the fourth lens is v4, and the following relational expression is satisfied: 60.00≦v4≦91.00

3. 2. The imaging optical lens according to claim 1, wherein an axial thickness of the second lens is d3, an axial thickness of the third lens is d5, and the following relational expression is satisfied: 1.68≦d5 / d3≦6.00

4. 2. The imaging optical lens according to claim 1, wherein the focal length of the fifth lens is f5, and the following relational expression is satisfied: 1.00≦f5 / f≦2.10

5. 2. The imaging optical lens according to claim 1, wherein an axial distance from an image side surface of the sixth lens to an image plane is defined as BF, and the following relational expression is satisfied: 0.20≦BF / TTL≦0.35

6. an object side surface of the first lens is a convex surface at a paraxial position, and an image side surface of the first lens is a concave surface at a paraxial position; 2. The imaging optical lens according to claim 1, wherein a focal length of the first lens is f1, a central radius of curvature of an object-side surface of the first lens is R1, a central radius of curvature of an image-side surface of the first lens is R2, an axial thickness of the first lens is d1, and the following relational expression is satisfied: −3.89≦f1 / f≦−1.01 0.82≦(R1+R2) / (R1-R2)≦3.22 0.02≦d1 / TTL≦0.34

7. an object side surface of the second lens is a concave surface at a paraxial position, and an image side surface of the second lens is a convex surface at a paraxial position; 2. The imaging optical lens according to claim 1, wherein a focal length of the second lens is f2, a central radius of curvature of an object-side surface of the second lens is R3, a central radius of curvature of an image-side surface of the second lens is R4, an axial thickness of the second lens is d3, and the following relational expression is satisfied: −95.3≦f2 / f≦37.04 -25.35≦(R3+R4) / (R3-R4)≦34.72 0.01≦d3 / TTL≦0.13

8. an object side surface of the third lens is a concave surface at a paraxial position, and an image side surface of the third lens is a convex surface at a paraxial position; 2. The imaging optical lens according to claim 1, wherein a focal length of the third lens is f3, a central radius of curvature of an object-side surface of the third lens is R5, a central radius of curvature of an image-side surface of the third lens is R6, an axial thickness of the third lens is d5, and the following relational expression is satisfied: −1980≦f3 / f≦−8.53 -16.53≦(R5+R6) / (R5-R6)≦-3.57 0.07≦d5 / TTL≦0.28

9. an object side surface of the fourth lens is a convex surface at a paraxial position, and an image side surface of the fourth lens is a convex surface at a paraxial position, 2. The imaging optical lens according to claim 1, wherein a focal length of the fourth lens is f4, a central radius of curvature of an object side surface of the fourth lens is R7, a central radius of curvature of an image side surface of the fourth lens is R8, an axial thickness of the fourth lens is d7, and the following relational expression is satisfied: 0.78≦f4 / f≦3.29 -0.65≦(R7+R8) / (R7-R8)≦0.06 0.03≦d7 / TTL≦0.22

10. The imaging optical lens according to claim 1 , wherein the first lens is made of a glass material, and the fourth lens is made of a glass material.

Images