Imaging optical lens

Abstract

To provide an imaging optical lens, in the field of an optical lens.SOLUTION: An imaging optical lens comprises, in order from the object side to the image side, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens and a seventh lens, wherein when an axial distance between the image side face of the third lens and the object side face of the fourth lens is represented by d6, an optical length of the imaging optical lens is represented by TTL, an angle of view of the imaging optical lens is represented by FOV, a total visual field image height in a diagonal direction of the imaging optical lens is represented by IH, a focal distance of the imaging optical lens is represented by f, a focal distance of the third lens is represented by f3, a central curvature radius of the object side face of the second lens is represented by R3, and a central curvature radius of the image side face of the second lens is represented by R4, conditional expressions: 0.06≤d6 / TTL≤0.20, 90.00≤(FOV×f) / IH≤140.00, 1.00≤f3 / f≤5.00, and 1.00≤R4 / R3≤15.00 are satisfied. The imaging optical lens has good optical performances such as a large diameter, a wide angle and ultra-thinness.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to the field of optical lenses, and more particularly to imaging optical lenses applied to mobile terminal devices such as smartphones and digital cameras, laser radar devices, and imaging devices such as monitors and PC lenses. [Background technology]

[0002] In recent years, the demand for miniaturization of imaging lenses has been increasing. For example, under the promotion of intelligent detection technology, 3D spatial detection technology based on laser radar has been actively developed. Laser radar lenses have the advantages of high detection accuracy, strong anti-interference ability, long coverage range, wide application range, etc., and are therefore applied in military and civilian fields. However, there are only two types of photosensitive elements in imaging lenses, namely, charge coupled devices (CCD) and complementary metal-oxide semiconductor sensors (CMOS sensors). With the progress of semiconductor manufacturing process technology, the pixel size of the photosensitive elements has been reduced, and miniaturized imaging lenses with good imaging quality have become the mainstream in the current market. In addition, with the development of technology and the increasing diversification needs of users, the pixel area of ​​the photosensitive elements is shrinking, and when the system's requirements for imaging quality are increasing, five-element, six-element, and seven-element lens configurations are gradually appearing in lens designs. Demand for wide-angle imaging optical lenses with excellent optical properties, large apertures and ultra-thin lenses is becoming increasingly urgent. Summary of the Invention [Problem to be solved by the invention]

[0003] The present invention has been made in view of the above problems, and has an object to provide an imaging optical lens that obtains high imaging performance and satisfies the requirements for a large aperture, an extremely thin lens, and a wide angle lens. [Means for solving the problem]

[0004] To solve the above technical problems, an embodiment of the present invention provides an imaging optical lens. the imaging optical lens is composed of, in order from the object side to the image side, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens; When the axial distance from the image side surface of the third lens to the object side surface of the fourth lens is d6, the optical length of the imaging optical lens is TTL, the angle of view of the imaging optical lens is FOV, the full field of view image height in the diagonal direction of the imaging optical lens is IH, the focal length of the imaging optical lens is f, the focal length of the third lens is f3, the central radius of curvature of the object side surface of the second lens is R3, and the central radius of curvature of the image side surface of the second lens is R4, the following conditional formulas (1) to (4) are satisfied. 0.06≦d6 / TTL≦0.20 (1) 90.00≦(FOV×f) / IH≦140.00 (2) 1.00≦f3 / f≦5.00 (3) 1.00≦R4 / R3≦15.00 (4)

[0005] It is preferable that, when the refractive index of the first lens is n1, the following conditional expression (5) is satisfied: 1.70≦n1≦2.10 (5)

[0006] Preferably, when the focal length of the fourth lens is f4 and the focal length of the fifth lens is f5, the following conditional expression (6) is satisfied. -4.00≦f4 / f5≦-0.60 (6)

[0007] It is preferable that, when the axial thickness of the second lens is d3 and the axial thickness of the third lens is d5, the following conditional expression (7) is satisfied. 1.20≦d3 / d5≦5.00 (7)

[0008] Preferably, the first lens has negative refractive power, and an image side surface of the first lens is concave in a paraxial direction; When 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, and the axial thickness of the first lens is d1, the following conditional expressions (8) to (10) are satisfied. -4.50≦f1 / f≦-1.40 (8) 0.24≦(R1+R2) / (R1−R2)≦2.57 (9) 0.03≦d1 / TTL≦0.20 (10)

[0009] Preferably, the object side surface of the second lens is a paraxially concave surface, and the image side surface of the second lens is a paraxially convex surface, When the focal length of the second lens is f2 and the axial thickness of the second lens is d3, the following conditional expressions (11) and (12) are satisfied. -13.03≦f2 / f≦18.87 (11) 0.09≦d3 / TTL≦0.20 (12)

[0010] Preferably, the third lens has positive refractive power, and an object side surface of the third lens is convex on a paraxial line, When 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, and the axial thickness of the third lens is d5, the following conditional expressions (13) and (14) are satisfied. -2.06≦(R5+R6) / (R5-R6)≦-0.30 (13) 0.03≦d5 / TTL≦0.09 (14)

[0011] Preferably, the fourth lens has negative refractive power, and an object side surface of the fourth lens is concave in a paraxial direction, When 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, and the axial thickness of the fourth lens is d7, the following conditional expressions (15) to (17) are satisfied. -6.91≦f4 / f≦-1.58 (15) -7.81≦(R7+R8) / (R7-R8)≦-0.07 (16) 0.01≦d7 / TTL≦0.04 (17)

[0012] Preferably, the fifth lens has positive refractive power, and an object side surface of the fifth lens is convex on a paraxial line, When the focal length of the fifth lens is f5, 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 axial thickness of the fifth lens is d9, the following conditional expressions (18) to (20) are satisfied. 1.70≦f5 / f≦3.63 (18) -2.38≦(R9+R10) / (R9-R10)≦-0.34 (19) 0.03≦d9 / TTL≦0.15 (20)

[0013] Preferably, the object side surface of the sixth lens is a paraxially convex surface, and the image side surface of the sixth lens is a paraxially concave surface, When the focal length of the sixth lens is f6, the central radius of curvature of the object side surface of the sixth lens is R11, the central radius of curvature of the image side surface of the sixth lens is R12, and the axial thickness of the sixth lens is d11, the following conditional expressions (21) to (23) are satisfied. -20.00≦f6 / f≦49.00 (21) -70.00≦(R11+R12) / (R11−R12)≦11.35 (22) 0.02≦d11 / TTL≦0.07 (23)

[0014] Preferably, the seventh lens has a positive refractive power, an object side surface of the seventh lens is a convex surface in a paraxial direction, and an image side surface of the seventh lens is a concave surface in a paraxial direction; When the focal length of the seventh lens is f7, the central radius of curvature of the object side surface of the seventh lens is R13, the central radius of curvature of the image side surface of the seventh lens is R14, and the axial thickness of the seventh lens is d13, the following conditional expressions (24) to (26) are satisfied. 4.60≦f7 / f≦70.00 (24) -17.00≦(R13+R14) / (R13−R14)≦39.00 (25) 0.04≦d13 / TTL≦0.25 (26)

[0015] Preferably, the first lens and / or the second lens and / or the third lens and / or the fourth lens and / or the fifth lens and / or the sixth lens and / or the seventh lens are made of a glass material. Effect of the Invention

[0016] The beneficial effects of the present invention are as follows: The imaging optical lens according to the present invention has excellent optical properties, meets the requirements for a large aperture, an extremely thin structure, and a wide angle, and is particularly applicable to imaging lens units of mobile phones that are configured with imaging elements such as high-pixel CCDs and CMOSs, web imaging lenses, and laser radar lenses.

[0017] In order to more clearly explain the technical solutions of the embodiments of the present invention, the following briefly introduces drawings required for the embodiments. Obviously, the drawings described below are only some embodiments of the present invention, and those skilled in the art can further obtain other drawings based on these drawings without any creative work. [Brief description of the drawings]

[0018] [Figure 1] 1 is a schematic diagram showing a configuration of an imaging optical lens according to a first embodiment of the present invention. [Diagram 2] 2 is a schematic diagram showing the field curvature and distortion of the imaging optical lens shown in FIG. [Diagram 3] 2 is a schematic diagram showing chromatic aberration of magnification of the imaging optical lens shown in FIG. [Figure 4] 2 is a schematic diagram showing axial chromatic aberration of the imaging optical lens shown in FIG. [Diagram 5] FIG. 4 is a schematic diagram showing the configuration of an imaging optical lens according to a second embodiment of the present invention. [Figure 6] 6 is a schematic diagram showing the field curvature and distortion of the imaging optical lens shown in FIG. 5. [Figure 7] 6 is a schematic diagram showing chromatic aberration of magnification of the imaging optical lens shown in FIG. 5. [Figure 8] 6 is a schematic diagram showing the longitudinal chromatic aberration of the imaging optical lens shown in FIG. 5. [Figure 9] FIG. 11 is a schematic diagram showing the configuration of an imaging optical lens according to a third embodiment of the present invention. [Figure 10] 10A and 10B are schematic diagrams showing the field curvature and distortion of the imaging optical lens shown in FIG. [Figure 11] 10 is a schematic diagram showing chromatic aberration of magnification of the imaging optical lens shown in FIG. [Figure 12] 10 is a schematic diagram showing the longitudinal chromatic aberration of the imaging optical lens shown in FIG. [Figure 13] FIG. 11 is a schematic diagram showing the configuration of an imaging optical lens according to a fourth embodiment of the present invention. [Figure 14] 14 is a schematic diagram showing the field curvature and distortion of the imaging optical lens shown in FIG. 13. [Figure 15] 14 is a schematic diagram showing chromatic aberration of magnification of the imaging optical lens shown in FIG. 13. [Figure 16] 14 is a schematic diagram showing the longitudinal chromatic aberration of the imaging optical lens shown in FIG. 13. [Figure 17] FIG. 13 is a schematic diagram showing the configuration of an imaging optical lens according to a fifth embodiment of the present invention. [Figure 18] 18A to 18C are schematic diagrams showing the field curvature and distortion of the imaging optical lens shown in FIG. 17. [Figure 19] 18 is a schematic diagram showing chromatic aberration of magnification of the imaging optical lens shown in FIG. 17. [Figure 20] 18 is a schematic diagram showing the longitudinal chromatic aberration of the imaging optical lens shown in FIG. 17. [Figure 21] FIG. 1 is a schematic diagram showing a configuration of an imaging optical lens according to a comparative example of the present invention. [Figure 22] 22A to 22C are schematic diagrams showing the field curvature and distortion of the imaging optical lens shown in FIG. 21. [Figure 23] 22 is a schematic diagram showing chromatic aberration of magnification of the imaging optical lens shown in FIG. 21. [Figure 24]22 is a schematic diagram showing the longitudinal chromatic aberration of the imaging optical lens shown in FIG. 21. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] In order to make the objectives, solutions and advantages of the present invention clearer, the following describes in detail each embodiment of the present invention with reference to the drawings. However, it is understood by those skilled in the art that many technical details are described in each embodiment of the present invention in order to better understand the present invention. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solution claimed by the present invention can be realized.

[0020] (First embodiment) Referring to the drawings, the present invention provides a photographing optical lens 10. Fig. 1 shows a photographing optical lens 10 according to a first embodiment of the present invention, and the photographing optical lens 10 includes seven lenses. Specifically, the photographing 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, an aperture S1, a fourth lens L4, a fifth lens L5, a sixth lens L6, and a seventh lens L7. An optical element such as an optical filter GF may be provided between the seventh lens L7 and an image plane Si.

[0021] In this embodiment, the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, and the seventh lens L7 are all made of a glass material.

[0022] The first lens L1 is a spherical lens, the second lens L2 is a spherical lens, the third lens L3 is a spherical lens, the fourth lens L4 is a spherical lens, the fifth lens L5 is a spherical lens, the sixth lens L6 is an aspherical lens, and the seventh lens L7 is an aspherical lens.

[0023] In this embodiment, if the axial distance from the image side surface of the third lens L3 to the object side surface of the fourth lens L4 is defined as d6 and the optical length of the imaging optical lens 10 is defined as TTL, the conditional formula 0.06≦d6 / TTL≦0.20 is satisfied. This conditional formula specifies the ratio of the axial distance d6 from the image side surface of the third lens L3 to the object side surface of the fourth lens L4 to the optical length TTL of the imaging optical lens 10, and if it is within the specified range, the distance between the two lenses (the third lens L3 and the fourth lens L4) at the aperture is large and a smooth transition can be achieved, which is advantageous for improving image quality.

[0024] In this embodiment, if the angle of view of the imaging optical lens 10 is defined as FOV, the image height of the imaging optical lens 10 as IH, and the focal length of the imaging optical lens 10 as f, then the imaging optical lens 10 satisfies a conditional formula 90.00≦(FOV×f) / IH≦140.00. This conditional formula specifies the ratio of the product of the angle of view FOV of the imaging optical lens 10 and the focal length f of the imaging optical lens 10 to the image height IH of the imaging optical lens 10, and if the ratio is within the specified range, the imaging lens 10 can have both a large angle of view and a long focal length, and can realize imaging at medium to long distances. Preferably, the imaging lens satisfies the conditional formula FOV≧70.00 so that the lens satisfies the requirement for a wide angle.

[0025] In this embodiment, the focal length of the third lens L3 is defined as f3, and the conditional formula 1.00≦f3 / f≦5.00 is satisfied. This conditional formula specifies the ratio between the focal length f3 of the third lens L3 and the focal length f of the imaging optical lens 10, and controls the focal length value of the single lens. When the focal length is within the specified range, the focal length can be reasonably distributed, which is favorable for controlling the temperature drift and has good temperature performance.

[0026] In this embodiment, if the central radius of curvature of the object side surface of the second lens L2 is defined as R3 and the central radius of curvature of the image side surface of the second lens L2 is defined as R4, the conditional formula 1.00≦R4 / R3≦15.00 is satisfied. This conditional formula defines the shape of the second lens L2 and, within the defined range, can reduce the degree of deflection of light passing through the lens, which is advantageous for correcting problems such as aberrations at off-axis angles of view.

[0027] When the angle of view of the imaging optical lens 10 of the present invention, the image height of the imaging optical lens 10, the optical length of the imaging optical lens 10, the focal length of the imaging optical lens 10, the focal lengths of the associated lenses, the thicknesses of the associated lenses, and the central radii of curvature of the object-side surfaces and the central radii of curvature of the image-side surfaces of the associated lenses satisfy the above conditional expressions, the imaging optical lens 10 can be made large-diameter, extremely thin, and wide-angle, and can have good optical performance.

[0028] In this embodiment, if the refractive index of the first lens L1 is defined as n1, the conditional formula 1.70≦n1≦2.10 is satisfied, and it is preferable to select and use a high refractive index material for the first lens L1, which is advantageous for reducing the tip diameter and improving the imaging quality.

[0029] In this embodiment, if the focal length of the fourth lens L4 is defined as f4 and the focal length of the fifth lens L5 is defined as f5, the conditional formula -4.00≦f4 / f5≦-0.60 is satisfied. This conditional formula specifies the ratio between the focal length f4 of the fourth lens L4 and the focal length f5 of the fifth lens L5, and if it is within the specified range, the focal length values ​​of the fourth lens L4 and the fifth lens L5 become close to each other, which is favorable for a gradual transition of light rays and improves image quality.

[0030] In this embodiment, if the axial thickness of the second lens L2 is defined as d3 and the axial thickness of the third lens L3 is defined as d5, the condition 1.20≦d3 / d5≦5.00 is satisfied. This condition specifies the ratio between the axial thickness d3 of the second lens L2 and the axial thickness d5 of the third lens L3, and if it is within the specified range, it is advantageous for achieving a wide angle of the lens.

[0031] In this embodiment, the object side surface of the first lens L1 is a paraxially convex surface, and the image side surface of the first lens L1 is a paraxially concave surface, and the first lens L1 has a negative refractive power. In other optional embodiments, the object side surface and the image side surface of the first lens L1 may be arranged in other concave-convex distribution conditions, and the first lens L1 may have a positive refractive power.

[0032] In this embodiment, when the focal length of the first lens L1 is defined as f1, the conditional formula −4.50≦f1 / f≦−1.40 is satisfied. This conditional formula specifies the ratio between the focal length f1 of the first lens L1 and the focal length f of the imaging optical lens 10, and the refractive power is appropriately distributed, so that the lens has excellent imaging quality and low sensitivity.

[0033] In this embodiment, if the central radius of curvature of the object side surface of first lens L1 is defined as R1 and the central radius of curvature of the image side surface of first lens L1 is defined as R2, the conditional formula 0.24≦(R1+R2) / (R1−R2)≦2.57 is satisfied. This conditional formula defines the shape of first lens L1 and, within the defined range, can reduce the degree of deflection of light passing through the lens, which is advantageous for correcting problems such as off-axis angle of view aberration.

[0034] In this embodiment, when the axial thickness of the first lens L1 is defined as d1, the conditional formula 0.03≦d1 / TTL≦0.20 is satisfied. This conditional formula specifies the ratio between the axial thickness d1 of the first lens L1 and the optical length TTL of the imaging optical lens 10, and is advantageous for achieving an extremely thin structure.

[0035] In this embodiment, the object side surface of the second lens L2 is a paraxial concave surface, and the image side surface of the second lens L2 is a paraxial convex surface, and the second lens L2 has a negative refractive power. In other optional embodiments, the object side surface and the image side surface of the second lens L2 may be arranged in other concave-convex distribution conditions, and the second lens L2 may have a positive refractive power.

[0036] In this embodiment, when the focal length of the second lens L2 is defined as f2, the conditional formula −13.03≦f2 / f≦18.87 is satisfied. This conditional formula specifies the ratio between the focal length f2 of the second lens L2 and the focal length f of the imaging optical lens 10, and the refractive power is appropriately distributed, so that the lens has excellent imaging quality and low sensitivity.

[0037] In this embodiment, the axial thickness d3 of the second lens L2 and the optical length TTL of the imaging optical lens 10 satisfy the conditional formula 0.09≦d3 / TTL≦0.20. This conditional formula defines the ratio between the axial thickness d3 of the second lens L2 and the optical length TTL of the imaging optical lens 10, and is advantageous for achieving an extremely thin structure.

[0038] In this embodiment, the object side surface of the third lens L3 is a paraxially convex surface, and the image side surface of the third lens L3 is a paraxially convex surface, and the third lens L3 has a positive refractive power. In other optional embodiments, the object side surface and the image side surface of the third lens L3 may be arranged in other concave-convex distribution conditions, and the third lens L3 may have a negative refractive power.

[0039] In this embodiment, if the central radius of curvature of the object side surface of the third lens L3 is defined as R5 and the central radius of curvature of the image side surface of the third lens L3 is defined as R6, the conditional formula -2.06≦(R5+R6) / (R5-R6)≦-0.30 is satisfied. This conditional formula defines the shape of the third lens L3 and, within the defined range, can reduce the degree of deflection of light passing through the lens, which is advantageous for correcting problems such as off-axis angle of view aberration.

[0040] In this embodiment, when the axial thickness of the third lens L3 is defined as d5, the conditional formula 0.03≦d5 / TTL≦0.09 is satisfied. This conditional formula specifies the ratio between the axial thickness d5 of the third lens L3 and the optical length TTL of the imaging optical lens 10, and is advantageous for achieving an extremely thin structure.

[0041] In this embodiment, the object side surface of the fourth lens L4 is a paraxial concave surface, and the image side surface of the fourth lens L4 is a paraxial convex surface, and the fourth lens L4 has a negative refractive power. In other optional embodiments, the object side surface and the image side surface of the fourth lens L4 may be arranged in other concave-convex distribution conditions, and the fourth lens L4 may have a positive refractive power.

[0042] In this embodiment, the focal length f4 of the fourth lens L4 and the focal length f of the imaging optical lens 10 satisfy the conditional formula −6.91≦f4 / f≦−1.58, which defines the ratio between the focal length f4 of the fourth lens L4 and the focal length f of the imaging optical lens 10 and appropriately distributes the refractive powers, so that the lens has excellent imaging quality and low sensitivity.

[0043] In this embodiment, if the central radius of curvature of the object side surface of fourth lens L4 is defined as R7 and the central radius of curvature of the image side surface of fourth lens L4 is defined as R8, the conditional formula -7.81≦(R7+R8) / (R7-R8)≦-0.07 is satisfied. This conditional formula defines the shape of fourth lens L4 and, within the defined range, can reduce the degree of deflection of light passing through the lens, which is advantageous for correcting problems such as off-axis angle of view aberration.

[0044] In this embodiment, when the axial thickness of the fourth lens L4 is defined as d7, the conditional formula 0.01≦d7 / TTL≦0.04 is satisfied. This conditional formula specifies the ratio between the axial thickness d7 of the fourth lens L4 and the optical length TTL of the imaging optical lens 10, and is advantageous for achieving an extremely thin structure.

[0045] In this embodiment, the object side surface of the fifth lens L5 is a paraxial convex surface, and the image side surface of the fifth lens L5 is a paraxial concave surface, and the fifth lens L5 has a positive refractive power. In other optional embodiments, the object side surface and the image side surface of the fifth lens L5 may be arranged in other concave-convex distribution conditions, and the fifth lens L5 may have a negative refractive power.

[0046] In this embodiment, the focal length f5 of the fifth lens L5 and the focal length f of the imaging optical lens 10 satisfy the conditional formula 1.70≦f5 / f≦3.63. This conditional formula specifies the ratio between the focal length f5 of the fifth lens L5 and the focal length f of the imaging optical lens 10, and by appropriately distributing the refractive power, the lens has excellent imaging quality and low sensitivity.

[0047] In this embodiment, if the central radius of curvature of the object side surface of fifth lens L5 is defined as R9 and the central radius of curvature of the image side surface of fifth lens L5 is defined as R10, the conditional formula -2.38≦(R9+R10) / (R9-R10)≦-0.34 is satisfied. This conditional formula defines the shape of fifth lens L5 and, within the defined range, can reduce the degree of deflection of light passing through the lens, which is advantageous for correcting problems such as off-axis angle of view aberration.

[0048] In this embodiment, if the axial thickness of the fifth lens L5 is defined as d9, the conditional expression 0.03≦d9 / TTL≦0.15 is satisfied, the ratio of the axial thickness d9 of the fifth lens L5 to the optical length TTL of the imaging optical lens 10 is specified, and this is advantageous for achieving an extremely thin structure.

[0049] In this embodiment, the sixth lens L6 has a paraxially convex object side surface and a paraxially concave image side surface, and the sixth lens L6 has a positive refractive power. In other optional embodiments, the object side surface and the image side surface of the sixth lens L6 may be arranged in other concave-convex distribution conditions, and the sixth lens L6 may have a negative refractive power.

[0050] In this embodiment, when the focal length of the sixth lens L6 is defined as f6, the conditional formula −20.00≦f6 / f≦49.00 is satisfied. This conditional formula specifies the ratio between the focal length f6 of the sixth lens L6 and the focal length f of the imaging optical lens 10, and the refractive power is appropriately distributed, so that the lens has excellent imaging quality and low sensitivity.

[0051] In this embodiment, if the central radius of curvature of the object side surface of the sixth lens L6 is defined as R11 and the central radius of curvature of the image side surface of the sixth lens L6 is defined as R12, the conditional formula -70.00≦(R11+R12) / (R11-R12)≦11.35 is satisfied. This conditional formula defines the shape of the sixth lens L6 and, within the defined range, can reduce the degree of deflection of light passing through the lens, which is advantageous for correcting problems such as off-axis angle of view aberration.

[0052] In this embodiment, when the axial thickness of the sixth lens L6 is defined as d11, the conditional formula 0.02≦d11 / TTL≦0.07 is satisfied. This conditional formula specifies the ratio between the axial thickness d11 of the sixth lens L6 and the optical length TTL of the imaging optical lens 10, and is advantageous for achieving an extremely thin structure.

[0053] In this embodiment, the seventh lens L7 has a paraxially convex object side surface and a paraxially concave image side surface, and the seventh lens L7 has a positive refractive power. In other optional embodiments, the object side surface and the image side surface of the seventh lens L7 may be arranged in other concave-convex distribution conditions, and the seventh lens L7 may have a negative refractive power.

[0054] In this embodiment, the focal length of the seventh lens L7 is defined as f7, and the focal length f7 of the seventh lens L7 and the focal length f of the imaging optical lens 10 satisfy the conditional formula 4.60≦f7 / f≦70.00. This conditional formula specifies the ratio between the focal length f7 of the seventh lens L7 and the focal length f of the imaging optical lens 10, and by appropriately distributing the refractive power, the lens has excellent imaging quality and low sensitivity.

[0055] In this embodiment, if the central radius of curvature of the object side surface of the seventh lens L7 is defined as R13 and the central radius of curvature of the image side surface of the seventh lens L7 is defined as R14, the conditional formula -17.00≦(R13+R14) / (R13-R14)≦39.00 is satisfied. This conditional formula defines the shape of the seventh lens L7 and, within the defined range, can reduce the degree of deflection of light passing through the lens, which is advantageous for correcting problems such as off-axis angle of view aberration.

[0056] In this embodiment, when the axial thickness of the seventh lens L7 is defined as d13, the conditional formula 0.04≦d13 / TTL≦0.25 is satisfied. This conditional formula specifies the ratio between the axial thickness d13 of the seventh lens L7 and the optical length TTL of the imaging optical lens 10, and is advantageous for achieving an extremely thin structure.

[0057] In this embodiment, if the aperture value of the imaging optical lens 10 is defined as Fno, then the conditional expression Fno≦1.30 is satisfied, and the lens satisfies the requirement for a wide angle.

[0058] The imaging optical lens 10 of the present invention will be described below using examples. The symbols used in each example indicate the following: The focal length, axial distance, central radius of curvature, axial thickness, inflection point position, and stationary point position are all in mm.

[0059] TTL: Optical length (the axial distance from the object side surface of the first lens L1 to the image plane Si), in mm.

[0060] In addition, inflection points and / or stationary points may be further set on the object side and / or image side of each lens to meet high-quality imaging needs, and specific embodiments are given below.

[0061] Table 1 shows the design data of the imaging optical lens 10 according to the first embodiment of the present invention.

[0062] [Table 1]

[0063] The meanings of the symbols are as follows: S1: Aperture R: Central radius of curvature at the center of the optical surface R1: The central radius of curvature of the object side of the first lens L1 R2: Radius of curvature of the center of the image side of the first lens L1 R3: The central radius of curvature of the object side of the second lens L2 R4: Radius of curvature of the center of the image side of the second lens L2 R5: The central radius of curvature of the object side of the third lens L3 R6: The central radius of curvature of the image side of the third lens L3 R7: The central radius of curvature of the object side of the fourth lens L4 R8: The central radius of curvature of the image side of the fourth lens L4 R9: The central radius of curvature of the object side of the fifth lens L5 R10: Radius of central curvature of the image side of the fifth lens L5 R11: The central radius of curvature of the object side of the sixth lens L6 R12: Radius of curvature of the center of the image side of the sixth lens L6 R13: The central radius of curvature of the object side of the seventh lens L7 R14: Radius of curvature of the center of the image side of the seventh lens L7 R15: The central curvature radius of the object side of the optical filter GF R16: Radius of curvature of the center of the image side of the optical filter GF d: Axial thickness of lens, axial distance between lenses d0: The axial distance from the aperture stop S1 to the object side of the first lens L1 d1: Axial thickness of the first lens L1 d2: The 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: The 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 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: The 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: the 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 seventh lens L7 d13: Axial thickness of the seventh lens L7 d14: The axial distance from the image side of the seventh lens L7 to the object side of the optical filter GF d15: On-axis thickness of optical filter GF d16: The axial distance from the image side of the optical filter GF to the image plane Si nd: Refractive index of d line nd1: refractive index of the first lens L1 at the d line 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 nd7: Refractive index of the d line of the seventh lens L7 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 v7: Abbe number of the seventh lens L7 vg: Abbe number of the optical filter GF

[0064] Table 2 shows aspheric data of the sixth lens L6 and the seventh lens L7 in the imaging optical lens 10 according to the first embodiment of the present invention.

[0065] [Table 2]

[0066] Here, k is a conic coefficient, and A4, A6, A8, A10, A12, A14, A16, A18, and A20 are aspheric coefficients.

[0067] y=(x 2 / R) / [1+{1―(k+1)(x 2 / R 2 )} 1 / 2 ]+A4x 4 +A6x 6 +A8x 8 +A10x 10 +A12x 12 +A14x 14 +A16x 16 +A18x 18 +A20x20 (27)

[0068] Here, x is the perpendicular distance between a point on the aspheric curve and the optical axis, and y is the aspheric depth (the perpendicular distance between a point on the aspheric surface that is x away from the optical axis and a tangent plane that is tangent to the vertex of the aspheric surface on the optical axis).

[0069] For convenience, the aspheric surface of each lens surface is expressed by the above formula (27). However, the present invention is not particularly limited to the aspheric polynomial of this formula (27).

[0070] 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. Here, P1R1 and P1R2 respectively indicate the object side surface and image side surface of the first lens L1, P2R1 and P2R2 respectively indicate the object side surface and image side surface of the second lens L2, P3R1 and P3R2 respectively indicate the object side surface and image side surface of the third lens L3, P4R1 and P4R2 respectively indicate the object side surface and image side surface of the fourth lens L4, P5R1 and P5R2 respectively indicate the object side surface and image side surface of the fifth lens L5, P6R1 and P6R2 respectively indicate the object side surface and image side surface of the sixth lens L6, and P7R1 and P7R2 respectively indicate the object side surface and image side surface of the seventh lens L7. The corresponding data in the "inflection point position" column is the vertical distance from the inflection point set on the surface of each lens to the optical axis of the imaging optical lens 10. The corresponding data in the “Stay Point Position” column is the vertical distance from the stay point located on the surface of each lens to the optical axis of the imaging optical lens 10 .

[0071] [Table 3]

[0072] [Table 4]

[0073] Fig. 2 is a schematic diagram showing the field curvature and distortion aberration after light with a wavelength of 940 nm passes through the imaging optical lens 10. The field curvature S in Fig. 2 is the field curvature in the sagittal direction, and T is the field curvature in the tangential direction. Figs. 3 and 4 are schematic diagrams showing the magnification chromatic aberration and axial chromatic aberration after light with wavelengths of 930 nm, 940 nm, and 950 nm, respectively, passes through the imaging optical lens 10.

[0074] As shown in Table 25, the first embodiment satisfies each of the conditional expressions.

[0075] In this embodiment, the entrance pupil diameter ENPD of the imaging optical lens 10 is 8.361 mm, the diagonal full-field image height IH is 9.615 mm, and the diagonal field of view FOV is 101.60°, so that the imaging optical lens 10 meets the design requirements of large aperture, wide angle, extremely thin, low sensitivity, and medium to long distance imaging, its on-axis and off-axis chromatic aberrations are sufficiently corrected, and it has excellent optical properties.

[0076] Second embodiment FIG. 5 is a schematic diagram showing the configuration of the imaging optical lens 20 in the second embodiment. The second embodiment is basically the same as the first embodiment, and the symbols have the same meanings as in the first embodiment. Therefore, the same parts will not be described repeatedly here, and only the differences will be described below.

[0077] In this embodiment, the sixth lens L6 has negative refractive power.

[0078] Table 5 shows design data for the imaging optical lens 20 according to the second embodiment of the present invention.

[0079] [Table 5]

[0080] Table 6 shows aspheric data of the sixth lens L6 and the seventh lens L7 in the imaging optical lens 20 according to the second embodiment of the present invention.

[0081] [Table 6]

[0082] Tables 7 and 8 show design data for the inflection points and stationary points of each lens in the imaging optical lens 20 according to the second embodiment of the present invention.

[0083] [Table 7]

[0084] [Table 8]

[0085] Fig. 6 is a schematic diagram showing the field curvature and distortion aberration after light with a wavelength of 940 nm passes through the imaging optical lens 20. The field curvature S in Fig. 6 is the field curvature in the sagittal direction, and T is the field curvature in the tangential direction. Figs. 7 and 8 are schematic diagrams showing the magnification chromatic aberration and axial chromatic aberration after light with wavelengths of 930 nm, 940 nm, and 950 nm, respectively, passes through the imaging optical lens 20.

[0086] As shown in Table 25, the second embodiment satisfies each of the conditional expressions.

[0087] In this embodiment, the entrance pupil diameter ENPD of the imaging optical lens 20 is 11.315 mm, the full field of view image height IH in the diagonal direction is 9.615 mm, and the diagonal angle of view FOV is 70.84°, so that the imaging optical lens 20 meets the design requirements of large aperture, wide angle, extremely thin, low sensitivity, and medium to long distance imaging, its on-axis and off-axis chromatic aberrations are sufficiently corrected, and it has excellent optical properties.

[0088] Third embodiment FIG. 9 is a schematic diagram showing the configuration of the imaging optical lens 30 in the third embodiment. The third embodiment is basically the same as the first embodiment, and the symbols have the same meanings as in the first embodiment. Therefore, the same parts will not be described repeatedly here, and only the differences will be described below.

[0089] In this embodiment, the object side surface of the first lens L1 is paraxially concave, the second lens L2 has positive refractive power, and the image side surface of the fourth lens L4 is paraxially concave.

[0090] Table 9 shows design data for the imaging optical lens 30 according to the third embodiment of the present invention.

[0091] [Table 9]

[0092] Table 10 shows aspheric data of the sixth lens L6 and the seventh lens L7 in the imaging optical lens 30 according to the third embodiment of the present invention.

[0093] [Table 10]

[0094] Tables 11 and 12 show design data for the inflection points and stationary points of each lens in the imaging optical lens 30 according to the third embodiment of the present invention.

[0095] [Table 11]

[0096] [Table 12]

[0097] Fig. 10 is a schematic diagram showing the field curvature and distortion aberration after light with a wavelength of 940 nm passes through the imaging optical lens 30. The field curvature S in Fig. 10 is the field curvature in the sagittal direction, and T is the field curvature in the tangential direction. Figs. 11 and 12 are schematic diagrams showing the magnification chromatic aberration and axial chromatic aberration after light with wavelengths of 930 nm, 940 nm, and 950 nm, respectively, passes through the imaging optical lens 30.

[0098] As shown in Table 25, the third embodiment satisfies each of the conditional expressions.

[0099] In this embodiment, the entrance pupil diameter ENPD of the imaging optical lens 30 is 12.153 mm, the full field of view image height IH in the diagonal direction is 9.615 mm, and the diagonal angle of view FOV is 85.11°, so that the imaging optical lens 30 meets the design requirements of large aperture, wide angle, extremely thin, low sensitivity, and medium to long distance imaging, its on-axis and off-axis chromatic aberrations are sufficiently corrected, and it has excellent optical properties.

[0100] (Fourth embodiment) FIG. 13 is a schematic diagram showing the configuration of an imaging optical lens 40 in the fourth embodiment. The fourth embodiment is basically the same as the first embodiment, and the meanings of the symbols are also the same as in the first embodiment. Therefore, the same parts will not be described here repeatedly, and only the differences will be described below.

[0101] In this embodiment, the image side surface of the fifth lens L5 is convex on the paraxial direction.

[0102] Table 13 shows design data for the imaging optical lens 40 according to the fourth embodiment of the present invention.

[0103] [Table 13]

[0104] Table 14 shows the aspheric surface data of the sixth lens L6 and the seventh lens L7 in the imaging optical lens 40 according to the fourth embodiment of the present invention.

[0105] [Table 14]

[0106] Tables 15 and 16 show design data for the inflection points and stationary points of each lens in the imaging optical lens 40 according to the fourth embodiment of the present invention.

[0107] [Table 15]

[0108] [Table 16]

[0109] Fig. 14 is a schematic diagram showing the field curvature and distortion aberration after light with a wavelength of 940 nm passes through the imaging optical lens 40. The field curvature S in Fig. 14 is the field curvature in the sagittal direction, and T is the field curvature in the tangential direction. Figs. 15 and 16 are schematic diagrams showing the magnification chromatic aberration and axial chromatic aberration after light with wavelengths of 930 nm, 940 nm, and 950 nm, respectively, passes through the imaging optical lens 40.

[0110] As shown in Table 25, the fourth embodiment satisfies each of the conditional expressions.

[0111] In this embodiment, the entrance pupil diameter ENPD of the imaging optical lens 40 is 7.644 mm, the full field of view image height IH in the diagonal direction is 9.615 mm, and the diagonal angle of view FOV is 88.61°, so that the imaging optical lens 40 meets the design requirements of large aperture, wide angle, extremely thin, low sensitivity, and medium to long distance imaging, its on-axis and off-axis chromatic aberrations are sufficiently corrected, and it has excellent optical properties.

[0112] Fifth embodiment FIG. 17 is a schematic diagram showing the configuration of the imaging optical lens 50 in the fifth embodiment. The fifth embodiment is basically the same as the first embodiment, and the symbols have the same meanings as in the first embodiment. Therefore, the same parts will not be described repeatedly here, and only the differences will be described below.

[0113] In this embodiment, the image side surface of the third lens L3 is a paraxial concave surface, and the image side surface of the fourth lens L4 is a paraxial concave surface.

[0114] Table 17 shows design data for the imaging optical lens 50 according to the fifth embodiment of the present invention.

[0115] [Table 17]

[0116] Table 18 shows aspheric data of the sixth lens L6 and the seventh lens L7 in the imaging optical lens 50 according to the fifth embodiment of the present invention.

[0117] [Table 18]

[0118] Tables 19 and 20 show design data for the inflection points and stationary points of each lens in the imaging optical lens 50 according to the fifth embodiment of the present invention.

[0119] [Table 19]

[0120] [Table 20]

[0121] Fig. 18 is a schematic diagram showing the field curvature and distortion aberration after light with a wavelength of 940 nm passes through the imaging optical lens 50. The field curvature S in Fig. 18 is the field curvature in the sagittal direction, and T is the field curvature in the tangential direction. Figs. 19 and 20 are schematic diagrams showing the lateral chromatic aberration and axial chromatic aberration after light with wavelengths of 930 nm, 940 nm, and 950 nm, respectively, passes through the imaging optical lens 50.

[0122] As shown in Table 25, the fifth embodiment satisfies each of the conditional expressions.

[0123] In this embodiment, the entrance pupil diameter ENPD of the imaging optical lens 50 is 7.397 mm, the full field of view image height IH in the diagonal direction is 9.615 mm, and the diagonal field of view FOV is 111.94°, so that the imaging optical lens 50 meets the design requirements of large aperture, wide angle, extremely thin, low sensitivity, and medium to long distance imaging, its on-axis and off-axis chromatic aberrations are sufficiently corrected, and it has excellent optical properties.

[0124] (Comparative Example)

[0125] FIG. 21 is a schematic diagram showing the structure of an imaging optical lens 60 in a comparative example, and since the meanings of the symbols are the same as those in the first embodiment, the same parts will not be described repeatedly here.

[0126] Table 21 shows the design data of the imaging optical lens 60 according to the comparative example of the present invention.

[0127] [Table 21]

[0128] Table 22 shows the aspheric data of the sixth lens L6 and the seventh lens L7 in the imaging optical lens 60 according to a comparative example of the present invention.

[0129] [Table 22]

[0130] Tables 23 and 24 show the design data of the inflection points and stationary points of each lens in the imaging optical lens 60 according to the comparative example of the present invention.

[0131] [Table 23]

[0132] [Table 24]

[0133] Fig. 22 is a schematic diagram showing the field curvature and distortion aberration after light with a wavelength of 940 nm passes through the imaging optical lens 60. The field curvature S in Fig. 22 is the field curvature in the sagittal direction, and T is the field curvature in the tangential direction. Figs. 23 and 24 are schematic diagrams showing the lateral chromatic aberration and axial chromatic aberration after light with wavelengths of 930 nm, 940 nm, and 950 nm, respectively, passes through the imaging optical lens 60.

[0134] In this comparative example, the entrance pupil diameter ENPD of the imaging optical lens 60 is 7.9876 mm, the full field of view image height IH in the diagonal direction is 9.615 mm, and the field angle FOV in the diagonal direction is 133.76°.

[0135] Table 25 shows various numerical values ​​and values ​​corresponding to parameters defined by conditional expressions in the first to fifth embodiments and the comparative example. Clearly, the imaging optical lens 60 according to the comparative example does not satisfy the conditional expression 90.00≦(FOV×f) / IH≦140.00. The imaging optical lens 60 cannot effectively combine a large angle of view and a long focal length, cannot realize imaging at medium to long distances, and does not have sufficiently excellent optical performance.

[0136] [Table 25]

[0137] Here, f12 is the composite focal length of the first lens L1 and the second lens L2.

[0138] The above is merely an embodiment of the present invention, and those skilled in the art may make modifications without departing from the spirit of the present invention, all of which are within the scope of protection of the present invention.

Claims

1. 1. An imaging optical lens, comprising: The optical system is constituted by, in order from the object side to the image side, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens, an axial distance from an image side surface of the third lens to an object side surface of the fourth lens is d6, an optical length of the imaging optical lens is TTL, an angle of view of the imaging optical lens is FOV, a total field of view image height in a diagonal direction of the imaging optical lens is IH, a focal length of the imaging optical lens is f, a focal length of the third lens is f3, a central radius of curvature of the object side surface of the second lens is R3, and a central radius of curvature of the image side surface of the second lens is R4, the imaging optical lens satisfies the following conditional expressions (1) to (4): 0.06≦d6 / TTL≦0.20 (1) 90.00≦(FOV×f) / IH≦140.00 (2) 1.00≦f3 / f≦5.00 (3) 1.00≦R4 / R3≦15.00 (4)

2. 2. The imaging optical lens according to claim 1, wherein the following conditional expression (5) is satisfied, where n1 is a refractive index of the first lens: 1.70≦n1≦2.10 (5)

3. 2. The imaging optical lens according to claim 1, wherein the following conditional expression (6) is satisfied, where the focal length of the fourth lens is f4 and the focal length of the fifth lens is f5: -4.00≦f4 / f5≦-0.60 (6)

4. 2. The photographic optical lens according to claim 1, wherein the following conditional expression (7) is satisfied when the axial thickness of the second lens is d3 and the axial thickness of the third lens is d5: 1.20≦d3 / d5≦5.00 (7)

5. the first lens has negative refractive power, and an image side surface of the first lens is concave in a paraxial direction; 2. The photographic optical lens according to claim 1, wherein the following conditional expressions (8) to (10) are satisfied when a focal length of the first lens is f1, a central radius of curvature of the object-side surface of the first lens is R1, a central radius of curvature of the image-side surface of the first lens is R2, and an axial thickness of the first lens is d1. -4.50≦f1 / f≦-1.40 (8) 0.24≦(R1+R2) / (R1-R2)≦2.57 (9) 0.03≦d1 / TTL≦0.20 (10)

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 convex surface, 2. The photographic optical lens according to claim 1, wherein the following conditional expressions (11) and (12) are satisfied, where f2 is a focal length of the second lens and d3 is an axial thickness of the second lens. −13.03≦f2 / f≦18.87 (11) 0.09≦d3 / TTL≦0.20 (12)

7. the third lens has a positive refractive power, and an object side surface of the third lens is a convex surface on a paraxial line; 2. The imaging optical lens according to claim 1, wherein the following conditional expressions (13) and (14) are satisfied when 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, and an axial thickness of the third lens is d5. -2.06≦(R5+R6) / (R5-R6)≦-0.30 (13) 0.03≦d5 / TTL≦0.09 (14)

8. the fourth lens has negative refractive power, and an object side surface of the fourth lens is a paraxial concave surface; the imaging optical lens according to claim 1, wherein the following conditional expressions (15) to (17) are satisfied when a focal length of the fourth lens is f4, a central radius of curvature of the object side surface of the fourth lens is R7, a central radius of curvature of the image side surface of the fourth lens is R8, and an axial thickness of the fourth lens is d7: −6.91≦f4 / f≦−1.58 (15) -7.81≦(R7+R8) / (R7-R8)≦-0.07 (16) 0.01≦d7 / TTL≦0.04 (17)

9. the fifth lens has positive refractive power, and an object side surface of the fifth lens is a convex surface on a paraxial line; the imaging optical lens according to claim 1, wherein the following conditional expressions (18) to (20) are satisfied when a focal length of the fifth lens is f5, a central radius of curvature of an object-side surface of the fifth lens is R9, a central radius of curvature of an image-side surface of the fifth lens is R10, and an axial thickness of the fifth lens is d9: 1.70≦f5 / f≦3.63 (18) -2.38≦(R9+R10) / (R9-R10)≦-0.34 (19) 0.03≦d9 / TTL≦0.15 (20)

10. an object side surface of the sixth lens is a paraxially convex surface, and an image side surface of the sixth lens is a paraxially concave surface, the imaging optical lens according to claim 1, wherein the following conditional expressions (21) to (23) are satisfied when a focal length of the sixth lens is f6, a central radius of curvature of an object-side surface of the sixth lens is R11, a central radius of curvature of an image-side surface of the sixth lens is R12, and an axial thickness of the sixth lens is d11: −20.00≦f6 / f≦49.00 (21) -70.00≦(R11+R12) / (R11-R12)≦11.35 (22) 0.02≦d11 / TTL≦0.07 (23)

11. the seventh lens has positive refractive power, an object side surface of the seventh lens is a convex surface in a paraxial direction, and an image side surface of the seventh lens is a concave surface in the paraxial direction; the imaging optical lens according to claim 1, wherein the following conditional expressions (24) to (26) are satisfied when a focal length of the seventh lens is f7, a central radius of curvature of the object side surface of the seventh lens is R13, a central radius of curvature of the image side surface of the seventh lens is R14, and an axial thickness of the seventh lens is d13: 4.60≦f7 / f≦70.00 (24) -17.00≦(R13+R14) / (R13-R14)≦39.00 (25) 0.04≦d13 / TTL≦0.25 (26)

12. 2. The imaging optical lens according to claim 1, wherein the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens are made of a glass material.

Images