Image capturing optical lens

Abstract

To provide an image capturing optical lens related to a field of an optical lens.SOLUTION: The image capturing optical lens consists of a first lens having positive refractive power, a second lens having negative refractive power, a third lens having negative refractive power, a fourth lens having refractive power, and a fifth lens having positive refractive power, and a sixth lens having negative refractive power, which are arranged in order from an object side to an image side, and satisfies the following conditional expressions: 0.10≤d8 / TTL≤0.20, -5.00≤R9 / R10≤-0.80, 0.70≤f2 / f3≤1.00, wherein f2 represents a focal length of the second lens, f3 represents a focal length of the third lens, d8 represents an axial distance from an image-side surface of the fourth lens to an object-side surface of the fifth lens, R9 represents a central curvature radius of an object-side surface of the fifth lens, R10 represents a central curvature radius of an image-side surface of the fifth lens, and TTL represents an optical length of the image capturing optical lens.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to the field of optical lenses, and particularly to an imaging optical lens 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 booming of various smart devices, the need for miniaturized imaging optical lenses has been increasing. In addition to the reduction of the pixel size of photosensitive elements, current electronic products tend to develop towards an outer shape with good functions and being thin, light, and portable. Therefore, a miniaturized imaging optical lens with good imaging quality has become the mainstream of the current market. In order to obtain excellent imaging quality, a multi-element lens structure is often adopted. Also, with the development of technology and the increasing diversification of user needs, when the pixel area of the photosensitive element is shrinking and the system requirements for imaging quality are increasing, a six-element lens structure is gradually emerging in lens design. There is a strong demand for a large-aperture and extremely thin imaging optical lens with good optical performance.

Summary of the Invention

Problems to be Solved by 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 and satisfying the design requirements of large aperture and extreme thinning.

Means for Solving the Problems

[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 positive refractive power, a second lens having a negative refractive power, a third lens having a negative refractive power, a fourth lens having a refractive power, a fifth lens having a positive refractive power, and a sixth lens having a negative refractive power. When the focal length of the second lens is f2, the focal length of the third lens is f3, the on-axis distance from the image-side surface of the fourth lens to the object-side surface of the fifth lens is d8, the central radius of curvature of the object-side surface of the fifth lens is R9, the central radius of curvature of the image-side surface of the fifth lens is R10, and the optical length of the imaging optical lens is TTL, the following conditional expressions (1) to (3) are satisfied. 0.10 ≦ d8 / TTL ≦ 0.20 (1) -5.00 ≦ R9 / R10 ≦ -0.80 (2) 0.70 ≦ f2 / f3 ≦ 1.00 (3)

[0005] Preferably, when the central radius of curvature of the object-side surface of the sixth lens is R11 and the central radius of curvature of the image-side surface of the sixth lens is R12, the following conditional expression (4) is satisfied. 0.16 ≦ R11 / R12 ≦ 0.64 (4)

[0006] Preferably, when the focal length of the imaging optical lens is f and the focal length of the first lens is f1, the following conditional expression (5) is satisfied. 0.40 ≦ f1 / f ≦ 0.50 (5)

[0007] Preferably, when the on-axis distance from the image-side surface of the third lens to the object-side surface of the fourth lens is d6 and the on-axis thickness of the fourth lens is d7, the following conditional expression (6) is satisfied. 2.00 ≦ d6 / d7 ≦ 4.00 (6)

[0008] Preferably, the object side surface of the first lens is convex in the paraxial region, the image side surface of the first lens is convex in the paraxial region, and when the radius of curvature of the center of the object side surface of the first lens is R1, the radius of curvature of the center of the image side surface of the first lens is R2, and the on-axis thickness of the first lens is d1, the following conditional expressions (7) to (8) are satisfied. -1.25 ≦ (R1 + R2) / (R1 - R2) ≦ -0.32 (7) 0.10 ≦ d1 / TTL ≦ 0.34 (8)

[0009] Preferably, the object side surface of the second lens is concave in the paraxial region, the image side surface of the second lens is concave in the paraxial region, and when the focal length of the imaging optical lens is f, the radius of curvature of the center of the object side surface of the second lens is R3, the radius of curvature of the center of the image side surface of the second lens is R4, and the on-axis thickness of the second lens is d3, the following conditional expressions (9) to (11) are satisfied. -2.25 ≦ f2 / f ≦ -0.61 (9) 0.38 ≦ (R3 + R4) / (R3 - R4) ≦ 1.37 (10) 0.01 ≦ d3 / TTL ≦ 0.06 (11)

[0010] Preferably, the object side surface of the third lens is convex in the paraxial region, the image side surface of the third lens is concave in the paraxial region, and when the focal length of the imaging optical lens is f, the radius of curvature of the center of the object side surface of the third lens is R5, the radius of curvature of the center of the image side surface of the third lens is R6, and the on-axis thickness of the third lens is d5, the following conditional expressions (12) to (14) are satisfied. -3.15 ≦ f3 / f ≦ -0.62 (12) 1.04 ≦ (R5 + R6) / (R5 - R6) ≦ 4.75 (13) 0.02 ≦ d5 / TTL ≦ 0.07 (14)

[0011] Preferably, when the focal length of the imaging optical lens is f, the focal length of the fourth lens is f4, the radius of curvature of the center of the object side surface of the fourth lens is R7, the radius of curvature of the center of the image side surface of the fourth lens is R8, and the on-axis thickness of the fourth lens is d7, the following conditional expressions (15) to (17) are satisfied. -34.78 ≦ f4 / f ≦ 28.49 (15) -5.49 ≦ (R7 + R8) / (R7 - R8) ≦ 1.62 (16) 0.02 ≦ d7 / TTL ≦ 0.07 (17)

[0012] Preferably, the object side surface of the fifth lens is convex in the paraxial region, the image side surface of the fifth lens is convex in the paraxial region, and when the focal length of the imaging optical lens is f, the focal length of the fifth lens is f5, and the on-axis thickness of the fifth lens is d9, the following conditional expressions (18) to (20) are satisfied. 0.95 ≦ f5 / f ≦ 3.59 (18) -0.22 ≦ (R9 + R10) / (R9 - R10) ≦ 1.00 (19) 0.04 ≦ d9 / TTL ≦ 0.15 (20)

[0013] Preferably, the object side surface of the sixth lens is concave in the paraxial region, the image side surface of the sixth lens is convex in the paraxial region, and when the focal length of the imaging optical lens is f, the focal length of the sixth lens is f6, the radius of curvature of the center of the object side surface of the sixth lens is R11, the radius of curvature of the center of the image side surface of the sixth lens is R12, and the on-axis thickness of the sixth lens is d11, the following conditional expressions (21) to (23) are satisfied. -4.17 ≦ f6 / f ≦ -0.60 (21) -9.09 ≦ (R11 + R12) / (R11 - R12) ≦ -0.92 (22) 0.02 ≦ d11 / TTL ≦ 0.15 (23)

Advantages of the Invention

[0014] The imaging optical lens according to the present invention has excellent optical characteristics and characteristics of large aperture and extremely thin thickness, and is particularly applicable to an imaging lens unit of a mobile phone and a WEB imaging lens composed of imaging elements such as CCD and CMOS for high pixels.

[0015] To more clearly explain the technical solution of the embodiment of the present invention, the drawings necessary for the embodiment are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, on the premise of not performing creative labor, other drawings can be obtained based on these drawings.

Brief Explanation of Drawings

[0016]

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Embodiments for Carrying Out the Invention

[0017] In order to make the object, solution means, and merits of the present invention clearer, each embodiment of the present invention will be described in detail below with reference to the drawings. It can be understood by those skilled in the art that many technical details are described in order to better understand the present invention in each embodiment of the present invention. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solutions claimed by the present invention can also be realized.

[0018] (First Embodiment) As shown in the 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 the imaging optical lens 10 includes a total of six lenses. Specifically, the imaging optical lens 10 includes, in order from the object side to the image side, a first lens L1, a diaphragm S1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, and a sixth lens L6. An optical element such as an optical filter GF may be installed between the sixth lens L6 and the image plane Si.

[0019] In the present embodiment, the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, and the sixth lens L6 are all made of a plastic material. In other selectable embodiments, each lens may be made of other materials.

[0020] In the present embodiment, when the on-axis distance from the image-side surface of the fourth lens L4 to the object-side surface of the fifth lens L5 is d8 and the optical length of the imaging optical lens 10 is TTL, the conditional expression 0.10 ≦ d8 / TTL ≦ 0.20 is satisfied, the ratio of the air interval between the fourth lens L4 and the fifth lens L5 to the optical length is defined, and within the range of the conditional expression, by reasonably distributing the air interval, it is advantageous for realizing telephoto imaging.

[0021] In the present embodiment, when the radius of curvature of the center of the object-side surface of the fifth lens L5 is R9 and the radius of curvature of the center of the image-side surface of the fifth lens L5 is R10, the conditional expression -5.00 ≦ R9 / R10 ≦ -0.80 is satisfied, the shape of the fifth lens L5 is defined, and within the range of the conditional expression, the degree of deflection of light passing through the lens can be relaxed, chromatic aberration can be effectively corrected, and the chromatic aberration |LC| ≦ 3.0 μm.

[0022] In this embodiment, when the focal length of the second lens L2 is f2 and the focal length of the third lens L3 is f3, the conditional expression 0.70 ≦ f2 / f3 ≦ 1.00 is satisfied, the ratio of the focal lengths of the second lens L2 and the third lens L3 is defined, and within the range of the conditional expression, by reasonably distributing the optical focal length of the system, the system has excellent imaging quality and low sensitivity.

[0023] In this embodiment, when the radius of curvature at the center of the object side surface of the sixth lens L6 is R11 and the radius of curvature at the center of the image side surface of the sixth lens L6 is R12, the conditional expression 0.16 ≦ R11 / R12 ≦ 0.64 is satisfied, the shape of the sixth lens L6 is defined, and within the range of the conditional expression, it contributes to the correction of the spherical aberration and distortion of the imaging optical lens, the distortion |Distortion| ≦ 2%, and the possibility of vignetting is reduced.

[0024] In this embodiment, when the focal length of the imaging optical lens 10 is f and the focal length of the first lens L1 is f1, the conditional expression 0.40 ≦ f1 / f ≦ 0.50 is satisfied, the ratio of the focal lengths of the first lens L1 and the system is defined, and within the range of the conditional expression, by reasonably distributing the optical focal length of the system, it contributes to the incidence of light and ensures the amount of transmitted light.

[0025] In this embodiment, when the on-axis distance from the image side surface of the third lens L3 to the object side surface of the fourth lens L4 is d6 and the on-axis thickness of the fourth lens L4 is d7, the conditional expression 2.00 ≦ d6 / d7 ≦ 4.00 is satisfied, the ratio of the air space between the third lens L3 and the fourth lens L4 and the on-axis thickness of the fourth lens L4 is defined, and within the range of the conditional expression, it is advantageous for shortening the overall length of the optical system.

[0026] In this embodiment, the object side surface of the first lens L1 is convex in the paraxial region, the image side surface is convex in the paraxial region, and the first lens L1 has a positive refractive power. In other alternative embodiments, the object side surface and the image side surface of the first lens L1 may be arranged in other concave-convex distribution situations.

[0027] When the radius of curvature of the center of the object side surface of the first lens L1 is R1 and the radius of curvature of the center of the image side surface of the first lens L1 is R2, by satisfying the conditional expression -1.25 ≤ (R1 + R2) / (R1 - R2) ≤ -0.32 and reasonably controlling the shape of the first lens L1, the first lens L1 can effectively correct the spherical aberration of the system. Preferably, the conditional expression -0.78 ≤ (R1 + R2) / (R1 - R2) ≤ -0.40 is satisfied.

[0028] When the on-axis thickness of the first lens L1 is d1 and the optical length of the imaging optical lens 10 is TTL, by satisfying the conditional expression 0.10 ≤ d1 / TTL ≤ 0.34, within the range of the conditional expression, it is advantageous for realizing miniaturization. Preferably, the conditional expression 0.17 ≤ d1 / TTL ≤ 0.27 is satisfied.

[0029] In the present embodiment, the second lens L2 has a concave surface on the object side in the paraxial region and a concave surface on the image side in the paraxial region, and the second lens L2 has a negative refractive power. In other alternative embodiments, the object side surface and the image side surface of the second lens L2 may be arranged in other concave-convex distribution situations.

[0030] When the focal length of the imaging optical lens 10 is f and the focal length of the second lens L2 is f2, by satisfying the conditional expression -2.25 ≤ f2 / f ≤ -0.61 and controlling the negative power of the second lens L2 within a reasonable range, it is advantageous for correcting the aberration of the optical system. Preferably, the conditional expression -1.41 ≤ f2 / f ≤ -0.76 is satisfied.

[0031] When the radius of curvature of the center of the object side surface of the second lens L2 is R3 and the radius of curvature of the center of the image side surface of the second lens L2 is R4, by satisfying the conditional expression 0.38 ≤ (R3 + R4) / (R3 - R4) ≤ 1.37, the shape of the second lens L2 is defined, and within the range, with the progress of ultra-thin wide-angleization, it is advantageous for correcting the aberration of the off-axis field angle, etc. Preferably, the conditional expression 0.61 ≤ (R3 + R4) / (R3 - R4) ≤ 1.10 is satisfied.

[0032] When the on-axis thickness of the second lens L2 is d3 and the optical length of the imaging optical lens 10 is TTL, the conditional expression 0.01 ≦ d3 / TTL ≦ 0.06 is satisfied, and within the range of the conditional expression, it is advantageous for miniaturization. Preferably, the conditional expression 0.02 ≦ d3 / TTL ≦ 0.05 is satisfied.

[0033] In the present embodiment, the third lens L3 has a convex surface on the object side in the paraxial region and a concave surface on the image side in the paraxial region, and the third lens L3 has a negative refractive power. In other selectable embodiments, the object side surface and the image side surface of the third lens L3 may be arranged in other concave-convex distribution situations.

[0034] When the focal length of the imaging optical lens 10 is f and the focal length of the third lens L3 is f3, the conditional expression -3.15 ≦ f3 / f ≦ -0.62 is satisfied, and due to a reasonable distribution of power, the system has excellent imaging quality and low sensitivity. Preferably, the conditional expression -1.97 ≦ f3 / f ≦ -0.78 is satisfied.

[0035] When the radius of curvature of the center of the object side surface of the third lens L3 is R5 and the radius of curvature of the center of the image side surface of the third lens L3 is R6, the conditional expression 1.04 ≦ (R5 + R6) / (R5 - R6) ≦ 4.75 is satisfied, which defines the shape of the third lens L3, and within the range, it is advantageous for correcting off-axis aberrations and the like as the ultra-thin wide-angle effect progresses. Preferably, the conditional expression 1.67 ≦ (R5 + R6) / (R5 - R6) ≦ 3.80 is satisfied.

[0036] When the on-axis thickness of the third lens L3 is d5 and the optical length of the imaging optical lens 10 is TTL, the conditional expression 0.02 ≦ d5 / TTL ≦ 0.07 is satisfied, and within the range of the conditional expression, it is advantageous for miniaturization. Preferably, the conditional expression 0.03 ≦ d5 / TTL ≦ 0.06 is satisfied.

[0037] In the present embodiment, the fourth lens L4 has a convex or concave surface on the object side in the paraxial region and a concave or convex surface on the image side in the paraxial region, and the fourth lens L4 has a positive or negative refractive power.

[0038] When the focal length of the imaging optical lens 10 is f and the focal length of the fourth lens L4 is f4, the conditional expression -34.78 ≤ f4 / f ≤ 28.49 is satisfied. With a reasonable distribution of power, the system has excellent imaging quality and low sensitivity. Preferably, the conditional expression -21.74 ≤ f4 / f ≤ 22.79 is satisfied.

[0039] When the central radius of curvature of the object side surface of the fourth lens L4 is R7 and the central radius of curvature of the image side surface of the fourth lens L4 is R8, the conditional expression -5.49 ≤ (R7 + R8) / (R7 - R8) ≤ 1.62 is satisfied, which defines the shape of the fourth lens L4. Within the range, with the progress of ultra-thin wide-angleization, it is advantageous for correcting off-axis aberration and the like. Preferably, the conditional expression -3.43 ≤ (R7 + R8) / (R7 - R8) ≤ 1.30 is satisfied.

[0040] When the on-axis thickness of the fourth lens L4 is d7 and the optical length of the imaging optical lens 10 is TTL, the conditional expression 0.02 ≤ d7 / TTL ≤ 0.07 is satisfied. Within the range of the conditional expression, it is advantageous for realizing miniaturization. Preferably, the conditional expression 0.02 ≤ d7 / TTL ≤ 0.06 is satisfied.

[0041] In the present embodiment, the fifth lens L5 has a convex surface on the object side in the paraxial region and a convex surface on the image side in the paraxial region, and the fifth lens L5 has a positive refractive power. In other selectable embodiments, the object side surface and the image side surface of the fifth lens L5 may be arranged in other concave-convex distribution situations.

[0042] When the focal length of the imaging optical lens 10 is f and the focal length of the fifth lens L5 is f5, the conditional expression 0.95 ≤ f5 / f ≤ 3.59 is satisfied. With a reasonable distribution of power, the system has excellent imaging quality and low sensitivity. Preferably, the conditional expression 1.53 ≤ f5 / f ≤ 2.87 is satisfied.

[0043] When the radius of curvature of the object side surface of the fifth lens L5 is R9 and the radius of curvature of the image side surface of the fifth lens L5 is R10, the conditional expression -0.22 ≤ (R9 + R10) / (R9 - R10) ≤ 1.00 is satisfied, which defines the shape of the fifth lens L5. Within this range, it is advantageous for correcting aberrations of off-axis angles of view and the like as the ultra-thin wide-angle effect progresses. Preferably, the conditional expression -0.14 ≤ (R9 + R10) / (R9 - R10) ≤ 0.80 is satisfied.

[0044] When the on-axis thickness of the fifth lens L5 is d9 and the optical length of the imaging optical lens 10 is TTL, the conditional expression 0.04 ≤ d9 / TTL ≤ 0.15 is satisfied. Within the range of this conditional expression, it is advantageous for realizing miniaturization. Preferably, the conditional expression 0.06 ≤ d9 / TTL ≤ 0.12 is satisfied.

[0045] In the present embodiment, the object side surface of the sixth lens L6 is concave in the paraxial region, and the image side surface is convex in the paraxial region. The sixth lens L6 has a negative refractive power. In other selectable embodiments, the object side surface and the image side surface of the sixth lens L6 may be arranged in other concave-convex distribution situations.

[0046] When the focal length of the imaging optical lens 10 is f and the focal length of the sixth lens L6 is f6, the conditional expression -4.17 ≤ f6 / f ≤ -0.60 is satisfied. Through a reasonable distribution of power, the system has excellent imaging quality and low sensitivity. Preferably, the conditional expression -2.61 ≤ f6 / f ≤ -0.76 is satisfied.

[0047] When the radius of curvature of the object side surface of the sixth lens L6 is R11 and the radius of curvature of the image side surface of the sixth lens L6 is R12, the conditional expression -9.09 ≤ (R11 + R12) / (R11 - R12) ≤ -0.92 is satisfied, which defines the shape of the sixth lens L6. Within the range of this conditional expression, as the ultra-thin wide-angle effect progresses, it is advantageous for correcting aberrations of off-axis angles of view and the like. Preferably, the conditional expression -5.68 ≤ (R11 + R12) / (R11 - R12) ≤ -1.15 is satisfied.

[0048] When the on-axis thickness of the sixth lens L6 is d11 and the optical length of the imaging optical lens 10 is TTL, the conditional expression 0.02 ≦ d11 / TTL ≦ 0.15 is satisfied, and within the range of the conditional expression, it is advantageous for realizing miniaturization. Preferably, the conditional expression 0.03 ≦ d11 / TTL ≦ 0.12 is satisfied.

[0049] In the present embodiment, when the image height of the imaging optical lens 10 is IH and the optical length of the imaging optical lens 10 is TTL, the conditional expression TTL / IH ≦ 2.15 is satisfied, and thereby it is advantageous for realizing miniaturization.

[0050] In the present embodiment, the aperture value FNO of the imaging optical lens 10 is 1.90 or less, and thereby a large aperture is achieved and the imaging performance of the imaging optical lens is excellent.

[0051] The imaging optical lens 10 has good optical performance and can satisfy the design requirements of large aperture and extremely thin thickness. Based on the characteristics of the imaging optical lens 10, the imaging optical lens 10 is particularly applicable to an imaging lens assembly of a mobile phone and a WEB imaging lens composed of imaging elements such as CCDs and CMOSs for high pixels.

[0052] Hereinafter, the imaging optical lens 10 of the present invention will be described using examples. The symbols described in each example are shown below. 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.

[0053] TTL: The optical length (the on-axis distance from the object side surface of the first lens L1 to the image plane Si), and the unit is mm. Aperture value FNO: The ratio of the effective focal length of the imaging optical lens to the entrance pupil diameter.

[0054] Preferably, in order to satisfy the imaging demand of high quality, an inflection point and / or a stop point may be further provided on the object side surface and / or the image side surface of the lens, and specific embodiments are shown below.

[0055] Tables 1 and 2 show the design data of the imaging optical lens 10 according to the first embodiment of the present invention.

[0056] [Table 1]

[0057] However, the meanings of the symbols in the table are as follows. S1: Aperture R: Radius of curvature at the center of the optical surface R1: Center radius of curvature of the object side surface of the first lens L1 R2: Center radius of curvature of the image side surface of the first lens L1 R3: Center radius of curvature of the object side surface of the second lens L2 R4: Center radius of curvature of the image side surface of the second lens L2 R5: Center radius of curvature of the object side surface of the third lens L3 R6: Center radius of curvature of the image side surface of the third lens L3 R7: Center radius of curvature of the object side surface of the fourth lens L4 R8: Center radius of curvature of the image side surface of the fourth lens L4 R9: Center radius of curvature of the object side surface of the fifth lens L5 R10: Center radius of curvature of the image side surface of the fifth lens L5 R11: Center radius of curvature of the object side surface of the sixth lens L6 R12: Center radius of curvature of the image side surface of the sixth lens L6 R13: Center radius of curvature of the object side surface of the optical filter GF R14: Center radius of curvature of the image side surface of the optical filter GF d: Axial thickness of the lens, axial distance between lenses d0: Axial distance from the aperture 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: The on-axis distance from the image side surface of the third lens L3 to the object side surface of the fourth lens L4 d7: The on-axis thickness of the fourth lens L4 d8: The on-axis distance from the image side surface of the fourth lens L4 to the object side surface of the fifth lens L5 d9: The on-axis thickness of the fifth lens L5 d10: The on-axis distance from the image side surface of the fifth lens L5 to the object side surface of the sixth lens L6 d11: The on-axis thickness of the sixth lens L6 d12: The on-axis distance from the image side surface of the sixth lens L6 to the object side surface of the optical filter GF d13: The on-axis thickness of the optical filter GF d14: The on-axis distance from the image side surface of the optical filter GF 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

[0058] Table 2 shows the aspherical data of each lens in the imaging optical lens 10 according to the first embodiment of the present invention.

[0059]

Table 2

[0060] For the aspherical surfaces of each lens surface, for the sake of convenience, the aspherical surface represented by the following formula (24) is used. However, the present invention is not particularly limited to the form of the aspherical polynomial shown in this formula (24).

[0061] 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 +A22r 22 +A24r 24 +A26r 26 +A28r 28 +A30r 30 (24)

[0062] However, k is the conic coefficient, A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28, A30 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 in the aspherical surface is r and the tangent plane tangent to the vertex on the optical axis of the aspherical surface).

[0063] Tables 3 and 4 show 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. However, P1R1 and P1R2 respectively represent the object side surface and the image side surface of the first lens L1, P2R1 and P2R2 respectively represent the object side surface and the image side surface of the second lens L2, P3R1 and P3R2 respectively represent the object side surface and the image side surface of the third lens L3, P4R1 and P4R2 respectively represent the object side surface and the image side surface of the fourth lens L4, P5R1 and P5R2 respectively represent the object side surface and the image side surface of the fifth lens L5, and P6R1 and P6R2 respectively represent the object side surface and the image side surface of the sixth lens L6. The corresponding data in the "Inflection Point Position" column is the vertical distance from the inflection point installed on the surface of each lens to the optical axis of the imaging optical lens 10. The corresponding data in the "Stationary Point Position" column is the vertical distance from the stationary point installed on the surface of each lens to the optical axis of the imaging optical lens 10.

[0064] [Table 3]

[0065] [Table 4]

[0066] Figures 2 and 3 are schematic diagrams showing the axial chromatic aberration and lateral chromatic aberration after light of wavelengths 650 nm, 610 nm, 555 nm, 510 nm, 470 nm, and 435 nm passes through the imaging optical lens 10 according to the first embodiment. Figure 4 is a schematic diagram showing the field curvature and distortion aberration after light of wavelength 555 nm passes through the imaging optical lens 10 according to 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 tangential direction.

[0067] Table 25 described later shows the values corresponding to various numerical values and parameters defined by conditional expressions in each example.

[0068] As shown in Table 25, the first embodiment satisfies each conditional expression.

[0069] In this embodiment, the entrance pupil diameter ENPD of the imaging optical lens 10 is 3.724 mm, the full field image height IH is 3.133 mm, the angle of view FOV in the diagonal direction is 47.57°, and the imaging optical lens 10 satisfies the design requirements of large aperture and extremely thin, and its axial and off-axis chromatic aberrations are sufficiently corrected and has excellent optical characteristics.

[0070] (Second Embodiment) The second embodiment is basically the same as the first embodiment, and the meanings of the symbols are also the same as those in the first embodiment. Therefore, only the differences are shown below.

[0071] FIG. 5 shows an imaging optical lens 20 according to the second embodiment of the present invention.

[0072] Tables 5 and 6 show the design data of the imaging optical lens 20 according to the second embodiment of the present invention.

[0073]

Table 5

[0074] Table 6 shows the aspherical data of each lens in the imaging optical lens 20 according to the second embodiment of the present invention.

[0075]

Table 6

[0076] Tables 7 and 8 show 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.

[0077]

Table 7

[0078]

Table 8

[0079] Figs. 6 and 7 are schematic diagrams showing the axial chromatic aberration and lateral chromatic aberration after light with wavelengths of 650 nm, 610 nm, 555 nm, 510 nm, 470 nm, and 435 nm passes through the imaging optical lens 20 according to the second embodiment. Fig. 8 is a schematic diagram showing the field curvature and distortion after light with a wavelength of 555 nm passes through the imaging optical lens 20 according to the second embodiment. In Fig. 8, the field curvature S is the field curvature in the sagittal direction, and T is the field curvature in the tangential direction.

[0080] As shown in Table 25, the second embodiment satisfies each conditional expression.

[0081] In this embodiment, the entrance pupil diameter ENPD of the imaging optical lens 20 is 3.436 mm, the full field image height IH is 3.133 mm, the angular field of view FOV in the diagonal direction is 50.37°, the imaging optical lens 20 satisfies the design requirements of large aperture and extremely thin, and its axial and off-axis chromatic aberrations are sufficiently corrected and it has excellent optical characteristics.

[0082] (Third Embodiment) The third embodiment is basically the same as the first embodiment, and the meanings of the symbols are also the same as those in the first embodiment. Therefore, only the differences are shown below.

[0083] Fig. 9 shows the imaging optical lens 30 according to the third embodiment of the present invention.

[0084] Tables 9 and 10 show the design data of the imaging optical lens 30 according to the third embodiment of the present invention.

[0085] [Table 9]

[0086] Table 10 shows the aspherical data of each lens in the imaging optical lens 30 according to the third embodiment of the present invention.

[0087] [Table 10]

[0088] Tables 11 and 12 show the design data of the inflection points and stopping points of each lens in the imaging optical lens 30 according to the third embodiment of the present invention.

[0089] [Table 11]

[0090] [Table 12]

[0091] FIG. 10 and FIG. 11 are schematic diagrams showing the axial chromatic aberration and magnification chromatic aberration after light of wavelengths 650 nm, 610 nm, 555 nm, 510 nm, 470 nm, and 435 nm passes through the imaging optical lens 30 according to the third embodiment. FIG. 12 is a schematic diagram showing the field curvature and distortion aberration after light of wavelength 555 nm passes through the imaging optical lens 20 according to the second embodiment. In FIG. 12, the field curvature S is the field curvature in the sagittal direction, and T is the field curvature in the tangential direction.

[0092] As shown in Table 25, the third embodiment satisfies each conditional expression.

[0093] In the present embodiment, the entrance pupil diameter ENPD of the imaging optical lens 30 is 3.715 mm, the full field image height IH is 3.133 mm, the angle of view FOV in the diagonal direction is 47.65°, the imaging optical lens 30 satisfies the design requirements of large aperture and extremely thin, and its axial and off-axis chromatic aberrations are sufficiently corrected and it has excellent optical characteristics.

[0094] (Fourth Embodiment) The fourth embodiment is basically the same as the first embodiment, and the meanings of the symbols are also the same as those in the first embodiment. Therefore, only the differences are shown below.

[0095] FIG. 13 shows an imaging optical lens 40 according to the fourth embodiment of the present invention.

[0096] Tables 13 and 14 show the design data of the imaging optical lens 40 according to the fourth embodiment of the present invention.

[0097] [Table 13]

[0098] Table 14 shows the aspherical data of each lens in the imaging optical lens 40 according to the fourth embodiment of the present invention.

[0099] [Table 14]

[0100] Tables 15 and 16 show the design data of the inflection points and the stationary points of each lens in the imaging optical lens 40 according to the fourth embodiment of the present invention.

[0101] [Table 15]

[0102] [Table 16]

[0103] FIG. 14 and FIG. 15 are schematic diagrams showing the axial chromatic aberration and the magnification chromatic aberration after light of wavelengths 650 nm, 610 nm, 555 nm, 510 nm, 470 nm, and 435 nm passes through the imaging optical lens 40 according to the fourth embodiment. FIG. 16 is a schematic diagram showing the field curvature and the distortion aberration after light of wavelength 555 nm passes through the imaging optical lens 40 according to the fourth embodiment. In FIG. 16, the field curvature S is the field curvature in the sagittal direction, and T is the field curvature in the tangential direction.

[0104] As shown in Table 25, the fourth embodiment satisfies each conditional expression.

[0105] In this embodiment, the entrance pupil diameter ENPD of the imaging optical lens 40 is 3.397 mm, the full field image height IH is 3.133 mm, the angular field of view FOV in the diagonal direction is 47.82°, the imaging optical lens 40 satisfies the design requirements of large aperture and extremely thin, and its axial and off-axis chromatic aberrations are sufficiently corrected and has excellent optical characteristics.

[0106] (Fifth Embodiment) The fifth embodiment is basically the same as the first embodiment, and the meanings of the symbols are also the same as those in the first embodiment. Therefore, only the differences are shown below.

[0107] FIG. 17 shows an imaging optical lens 50 according to the fifth embodiment of the present invention.

[0108] Tables 17 and 18 show the design data of the imaging optical lens 50 according to the fifth embodiment of the present invention.

[0109]

Table 17

[0110] Table 18 shows the aspherical data of each lens in the imaging optical lens 50 according to the fifth embodiment of the present invention.

[0111]

Table 18

[0112] Tables 19 and 20 show 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.

[0113]

Table 19

[0114]

Table 20

[0115] Figures 18 and 19 are schematic diagrams showing the axial chromatic aberration and magnification chromatic aberration after light with wavelengths of 650 nm, 610 nm, 555 nm, 510 nm, 470 nm, and 435 nm passes through the imaging optical lens 50 according to the fifth embodiment. Figure 20 is a schematic diagram showing the field curvature and distortion aberration after light with a wavelength of 555 nm passes through the imaging optical lens 50 according to the fifth embodiment. In Figure 20, the field curvature S is the field curvature in the sagittal direction, and T is the field curvature in the tangential direction.

[0116] As shown in Table 25, the fifth embodiment satisfies each conditional expression.

[0117] In this embodiment, the entrance pupil diameter ENPD of the imaging optical lens 50 is 3.919 mm, the full field image height IH is 3.133 mm, the angular field of view FOV in the diagonal direction is 45.72°, the imaging optical lens 50 satisfies the design requirements of large aperture and extremely thin, its axial and off-axis chromatic aberrations are sufficiently corrected, and it has excellent optical characteristics.

[0118] (Comparative Embodiment) Since the meanings of the symbols in the comparative embodiment are the same as those in the first embodiment, only the differences are shown below.

[0119] Figure 21 shows the imaging optical lens 60 according to the comparative embodiment.

[0120] Tables 21 and 22 show the design data of the imaging optical lens 60 according to the comparative embodiment.

[0121] [Table 21]

[0122] Table 22 shows the aspherical data of each lens in the imaging optical lens 60 according to the comparative embodiment.

[0123]

Table 22

[0124] Tables 23 and 24 show the design data of the inflection points and stopping points of each lens in the imaging optical lens 60 according to the comparative embodiment.

[0125]

Table 23

[0126]

Table 24

[0127] FIGS. 22 and 23 are schematic diagrams showing the axial chromatic aberration and magnification chromatic aberration after light of wavelengths 650 nm, 610 nm, 555 nm, 510 nm, 470 nm, and 435 nm passes through the imaging optical lens 60 according to the comparative embodiment. FIG. 24 is a schematic diagram showing the field curvature and distortion aberration after light of wavelength 555 nm passes through the imaging optical lens 60 according to the comparative embodiment. In FIG. 24, the field curvature S is the field curvature in the sagittal direction, and T is the field curvature in the tangential direction.

[0128] In Table 25 below, the numerical values corresponding to each conditional expression in the comparative embodiment are listed according to the above conditional expressions. Obviously, the imaging optical lens 60 according to the comparative embodiment does not satisfy the above conditional expression 0.10 ≦ d8 / TTL ≦ 0.20.

[0129] In the comparative embodiment, the entrance pupil diameter ENPD of the imaging optical lens 60 is 3.625 mm, the full field image height IH is 3.133 mm, the angular field of view FOV in the diagonal direction is 41.50°, and the imaging optical lens 60 does not satisfy the design requirements of large aperture and extremely thin.

[0130]

Table 25

[0131] As those skilled in the art will understand, the above embodiments are specific embodiments for realizing the present invention, and in actual applications, various changes to the form and details are possible without departing from the gist 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 positive refractive power, a second lens having negative refractive power, a third lens having negative refractive power, a fourth lens having refractive power, a fifth lens having positive refractive power, and a sixth lens having negative refractive power; an optical lens satisfying the following conditional expressions (1) to (3): 0.10≦d8 / TTL≦0.20 (1) −5.00≦R9 / R10≦−0.80 (2) 0.70≦f2 / f3≦1.00 (3)

2. 2. The imaging optical lens according to claim 1, wherein the following conditional expression (4) is satisfied when a central radius of curvature of an object-side surface of the sixth lens is R11 and a central radius of curvature of an image-side surface of the sixth lens is R12: 0.16≦R11 / R12≦0.64 (4)

3. 2. The imaging optical lens according to claim 1, wherein the following conditional expression (5) is satisfied, where f is a focal length of the imaging optical lens and f1 is a focal length of the first lens: 0.40≦f1 / f≦0.50 (5)

4. 2. The imaging optical lens according to claim 1, wherein the following conditional expression (6) is satisfied when an axial distance from an image side surface of the third lens to an object side surface of the fourth lens is d6 and an axial thickness of the fourth lens is d7: 2.00≦d6 / d7≦4.00 (6)

5. an object side surface of the first lens is a paraxially convex surface, and an image side surface of the first lens is a paraxially convex surface, 2. The imaging optical lens according to claim 1, wherein when 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, and an axial thickness of the first lens is d1, the following conditional expressions (7) to (8) are satisfied: -1.25≦(R1+R2) / (R1-R2)≦-0.32 (7) 0.10≦d1 / TTL≦0.34 (8)

6. an object side surface of the second lens is a paraxially concave surface, and an image side surface of the second lens is a paraxially concave surface, 2. The imaging optical lens according to claim 1, wherein the imaging optical lens satisfies the following conditional expressions (9) to (11), where f is a focal length of the imaging optical lens, R3 is a central radius of curvature of the object side surface of the second lens, R4 is a central radius of curvature of the image side surface of the second lens, and d3 is an axial thickness of the second lens. −2.25≦f2 / f≦−0.61 (9) 0.38≦(R3+R4) / (R3-R4)≦1.37 (10) 0.01≦d3 / TTL≦0.06 (11)

7. an object side surface of the third lens is a paraxially convex surface, and an image side surface of the third lens is a paraxially concave surface, the imaging optical lens according to claim 1, wherein the imaging optical lens satisfies the following conditional expressions (12) to (14), where f is a focal length of the imaging optical lens, R5 is a central radius of curvature of the object side surface of the third lens, R6 is a central radius of curvature of the image side surface of the third lens, and d5 is an axial thickness of the third lens. −3.15≦f3 / f≦−0.62 (12) 1.04≦(R5+R6) / (R5-R6)≦4.75 (13) 0.02≦d5 / TTL≦0.07 (14)

8. 2. The imaging optical lens according to claim 1, wherein the imaging optical lens satisfies the following conditional expressions (15) to (17), where f is a focal length of the imaging optical lens, f4 is a focal length of the fourth lens, R7 is a central radius of curvature of the object side surface of the fourth lens, R8 is a central radius of curvature of the image side surface of the fourth lens, and d7 is an axial thickness of the fourth lens. −34.78≦f4 / f≦28.49 (15) -5.49≦(R7+R8) / (R7-R8)≦1.62 (16) 0.02≦d7 / TTL≦0.07 (17)

9. an object side surface of the fifth lens is a paraxially convex surface, and an image side surface of the fifth lens is a paraxially convex surface, 2. The imaging optical lens according to claim 1, wherein the imaging optical lens satisfies the following conditional expressions (18) to (20), where f is a focal length of the imaging optical lens, f5 is a focal length of the fifth lens, and d9 is an axial thickness of the fifth lens. 0.95≦f5 / f≦3.59 (18) -0.22≦(R9+R10) / (R9-R10)≦1.00 (19) 0.04≦d9 / TTL≦0.15 (20)

10. an object side surface of the sixth lens is a paraxial concave surface, and an image side surface of the sixth lens is a paraxial convex surface, 2. The imaging optical lens according to claim 1, wherein the imaging optical lens satisfies the following conditional expressions (21) to (23): −4.17≦f6 / f≦−0.60 (21) -9.09≦(R11+R12) / (R11-R12)≦-0.92 (22) 0.02≦d11 / TTL≦0.15 (23)

Images