Image capturing optical lens

Abstract

To provide an image capturing optical lens.SOLUTION: An image capturing optical lens consists of first and second lenses having negative refractive power, a third lens having positive refractive power, a fourth lens having positive refractive power, a fifth lens having negative refractive power, and a sixth lens having positive refractive power arranged in order from the object side to the image side, the first and third lenses being made of a glass material, and satisfies the following conditional expressions: n3≥1.70, 1.00≤f2 / f1≤2.00, 1.30≤d10 / d9≤4.00, 1.70≤R4 / R3≤4.00, 0.02≤TTL / (IH×FOV)≤0.03, when a refractive index of the third lens is defined as n3, a focal distance of the first lens is defined as f1, a focal distance of the second lens is defined as f2, an axial thickness of the fifth lens is defined as d9, an axial distance from an image-side surface of the fifth lens to an object-side surface of the sixth lens is defined as d10, a central curvature radius of an object-side surface of the second lens is defined as R3, a central curvature radius of an image-side surface is defined as R4, an optical length of the image capturing optical lens is defined as TTL, an image height is defined as IH, and a view angle is FOV.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 that are applied to mobile terminal devices such as smartphones and digital cameras, and imaging devices such as monitors, PC lenses, in-vehicle lenses, and drones. [Background technology]

[0002] In recent years, with the development of various smart devices, the demand for miniaturized imaging optical lenses is increasing. In addition to the reduction in pixel size of the photosensitive element, the current electronic products tend to develop with high functionality and lightweight, thin and portable appearance. Therefore, miniaturized imaging optical lenses with good imaging quality have become mainstream in the current market. In order to obtain good imaging quality, a multi-lens structure is often adopted. In addition, with the development of technology and the increasing diversification needs of users, when the pixel area of ​​the photosensitive element is shrinking and the system requirements for imaging quality are increasing, a six-lens structure is gradually appearing in the lens design. The demand for wide-angle imaging lenses with excellent optical properties, small volume and sufficient correction of aberration is becoming urgent. Summary of the Invention [Problem 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 that has good optical performance and satisfies design requirements for a large aperture, an ultra-wide angle, and compactness. [Means for solving the problem]

[0004] In order to solve the above problem, an embodiment of the present invention provides an imaging optical lens, the imaging optical lens including, in order from an object side to an image side, a first lens having negative refractive power, a second lens having negative refractive power, a third lens having positive refractive power, a fourth lens having positive refractive power, a fifth lens having negative refractive power, and a sixth lens having positive refractive power, the first lens being made of a glass material, the third lens being made of a glass material, and a refractive index of the third lens being is n3, the focal length of the first lens is f1, the focal length of the second lens is f2, the axial thickness of the fifth lens is d9, the axial distance from the image side surface of the fifth lens to the object side surface of the sixth lens is d10, the central radius of curvature of the object side surface of the second lens is R3, the central radius of curvature of the image side surface of the second lens is R4, the optical length of the imaging optical lens is TTL, the image height of the imaging optical lens is IH, and the angle of view of the imaging optical lens is FOV, the following conditional formulas (1) to (5) are satisfied. n3≧1.70 (1) 1.00≦f2 / f1≦2.00 (2) 1.30≦d10 / d9≦4.00 (3) 1.70≦R4 / R3≦4.00 (4) 0.02≦TTL / (IH×FOV)≦0.03 (5)

[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 formula (6) is satisfied. -3.50≦(R11+R12) / (R11-R12)≦-1.30 (6)

[0006] Preferably, when the focal length of the imaging optical lens is f and the focal length of the third lens is f3, the following conditional expression (7) is satisfied. 1.10≦f3 / f≦1.50 (7)

[0007] Preferably, the object side surface of the first lens is a convex surface paraxially, the image side surface of the first lens is a concave surface paraxially, and when a focal length of the imaging optical lens is f, 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, the following conditional expressions (8) to (10) are satisfied. -3.69≦f1 / f≦-0.98 (8) 0.52≦(R1+R2) / (R1-R2)≦2.29 (9) 0.02≦d1 / TTL≦0.16 (10)

[0008] Preferably, the object side surface of the second lens is a paraxial concave surface, the image side surface of the second lens is a paraxial convex surface, and when a focal length of the imaging optical lens is f and an axial thickness of the second lens is d3, the following conditional expressions (11) to (13) are satisfied. -7.07≦f2 / f≦-1.27 (11) -7.70≦(R3+R4) / (R3-R4)≦-1.12 (12) 0.02≦d3 / TTL≦0.09 (13)

[0009] Preferably, the object side surface of the third lens is a convex surface paraxially, the image side surface of the third lens is a convex surface paraxially, and when a central radius of curvature of the object side surface of the third lens is R5, a central radius of curvature of the image side surface of the third lens is R6, and an axial thickness of the third lens is d5, the following conditional expressions (14) to (15) are satisfied. -0.44≦(R5+R6) / (R5-R6)≦-0.05 (14) 0.03≦d5 / TTL≦0.12 (15)

[0010] Preferably, the object side surface of the fourth lens is a convex surface paraxially, the image side surface of the fourth lens is a convex surface paraxially, and when the focal length of the imaging optical lens is f, 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 (16) to (18) are satisfied. 0.53≦f4 / f≦1.86 (16) 0.20≦(R7+R8) / (R7-R8)≦0.69 (17) 0.06≦d7 / TTL≦0.20 (18)

[0011] Preferably, the object side surface of the fifth lens is a paraxially concave surface, the image side surface of the fifth lens is a paraxially concave surface, and when a focal length of the imaging optical lens is f, a focal length of the fifth lens is f5, a central radius of curvature of the object side surface of the fifth lens is R9, and a central radius of curvature of the image side surface of the fifth lens is R10, the following conditional expressions (19) to (21) are satisfied. -3.15≦f5 / f≦-0.78 (19) -1.73≦(R9+R10) / (R9-R10)≦-0.51 (20) 0.02≦d9 / TTL≦0.11 (21)

[0012] Preferably, the object side surface of the sixth lens is a paraxial convex surface, the image side surface of the sixth lens is a paraxial concave surface, and when the focal length of the imaging optical lens is f, the focal length of the sixth lens is f6, and the axial thickness of the sixth lens is d11, the following conditional expressions (22) to (23) are satisfied. 1.48≦f6 / f≦6.86 (22) 0.06≦d11 / TTL≦0.22 (23)

[0013] Preferably, when the angle of view of the imaging optical lens is FOV, the following conditional expression (24) is satisfied: FOV≧120° (24) Effect of the Invention

[0014] The beneficial effects of the present invention are as follows: The imaging optical lens according to the present invention has excellent optical properties, and has the properties of a large aperture, an ultra-wide angle, and a small size, and is particularly applicable to mobile phone imaging lens assemblies, web imaging lenses, and imaging lenses for drones, which are composed of imaging elements such as CCD and CMOS for high pixels. [Brief description of the drawings]

[0015] 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. [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 axial chromatic aberration 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 the field curvature and distortion 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 longitudinal chromatic aberration 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 field curvature and distortion 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] 10 is a schematic diagram showing the longitudinal chromatic aberration 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 field curvature and distortion 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 longitudinal chromatic aberration 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 field curvature and distortion 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] 18 is a schematic diagram showing the longitudinal chromatic aberration 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 field curvature and distortion of the imaging optical lens shown in FIG. 17. [Figure 21] FIG. 13 is a schematic diagram showing the configuration of an imaging optical lens according to a sixth embodiment of the present invention. [Figure 22] 22 is a schematic diagram showing the longitudinal chromatic aberration 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] 22A to 22C are schematic diagrams showing the field curvature and distortion of the imaging optical lens shown in FIG. 21. [Diagram 25] FIG. 13 is a schematic diagram showing a configuration of an imaging optical lens according to a comparative embodiment. [Figure 26] FIG. 26 is a schematic diagram showing the longitudinal chromatic aberration of the imaging optical lens shown in FIG. [Figure 27] 26 is a schematic diagram showing chromatic aberration of magnification of the imaging optical lens shown in FIG. 25. [Figure 28] 26 is a schematic diagram showing the field curvature and distortion of the imaging optical lens shown in FIG. 25. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] 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.

[0017] (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 a first embodiment of the present invention, which includes a total of six lenses. Specifically, the imaging optical lens 10 is composed of, in order from the object side to the image side, a protective sheet PG, a first lens L1, a second lens L2, a third lens L3, a diaphragm S1, a fourth lens L4, a fifth lens L5, and a sixth lens L6. An optical element such as an optical filter GF may be provided between the sixth lens L6 and an image surface Si.

[0018] In this embodiment, the object side and image side surfaces of the first lens L1 are both spherical, and the surfaces of the remaining lenses are all aspheric. By designing some of the lenses as spherical lenses, the manufacturing difficulty can be reduced.

[0019] In this embodiment, the first lens L1 is made of glass, the second lens L2 is made of plastic, the third lens L3 is made of glass, the fourth lens L4 is made of plastic, the fifth lens L5 is made of plastic, and the sixth lens L6 is made of plastic, and the addition of glass lenses can improve the optical performance of the system. In other alternative embodiments, each lens may be made of other materials.

[0020] In this embodiment, when the refractive index of the third lens L3 is n3, the conditional expression n3≧1.70 is satisfied, thereby defining the refractive index n3 of the third lens L3. Using a material with a high refractive index within this range contributes to improving the imaging quality.

[0021] In this embodiment, when the focal length of the first lens L1 is f1 and the focal length of the second lens L2 is f2, the conditional formula 1.00≦f2 / f1≦2.00 is satisfied, thereby defining the ratio between the focal length f1 of the first lens L1 and the focal length f2 of the second lens L2. Within this range, the focal lengths of the first lens and the second lens are close to each other, which contributes to a gradual transition of light rays and effectively reduces chromatic aberration, and |LC|≦4.5 μm.

[0022] In this embodiment, when the axial thickness of the fifth lens L5 is d9 and the axial distance from the image side surface of the fifth lens L5 to the object side surface of the sixth lens L6 is d10, the conditional formula 1.30≦d10 / d9≦4.00 is satisfied, thereby specifying the ratio of the axial distance d10 from the image side surface of the fifth lens L5 to the object side surface of the sixth lens L6 to the axial thickness d9 of the fifth lens L5. By allocating the air space within this range, it is possible to contribute to a gradual transition of light rays and improve image quality.

[0023] In this embodiment, when the central radius of curvature of the object side surface of the second lens L2 is R3 and the central radius of curvature of the image side surface of the second lens L2 is R4, the conditional formula 1.70≦R4 / R3≦4.00 is satisfied, thereby defining the shape of the second lens L2, and within the range of the conditional formula, the amount of field curvature of the system can be effectively balanced, and the shift amount of the field curvature in the central field of view can be made less than 0.01 mm.

[0024] In this embodiment, when the optical length of the imaging optical lens 10 is TTL, the image height of the imaging optical lens 10 is IH, and the angle of view of the imaging optical lens 10 is FOV, the conditional formula 0.02≦TTL / (IH×FOV)≦0.03 is satisfied, which specifies the ratio of the optical length TTL of the imaging optical lens 10 to the product of the image height IH and the angle of view FOV, and contributes to achieving both a compact system and a wide angle within the range of the conditional formula.

[0025] In this embodiment, when the central radius of curvature of the object side surface of the sixth lens L6 is R11 and the central radius of curvature of the image side surface of the sixth lens L6 is R12, the conditional formula -3.50≦(R11+R12) / (R11-R12)≦-1.30 is satisfied, which defines the shape of the sixth lens L6, contributes to a gradual transition of light rays, and improves image quality.

[0026] In this embodiment, 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 formula 1.10≦f3 / f≦1.50 is satisfied, thereby defining the ratio between the focal length f3 of the third lens L3 and the focal length f of the imaging optical lens 10. By appropriately allocating the refractive power of the system within this range, the system has good imaging quality and low sensitivity.

[0027] In this embodiment, the first lens L1 has a paraxially convex object side surface and a paraxially concave image side surface, and has negative 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.

[0028] 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 formula -3.69≦f1 / f≦-0.98 is satisfied, which defines the ratio between the focal length f1 of the first lens L1 and the focal length f of the imaging optical lens 10, and within this range, it contributes to realizing an ultra-wide angle. Preferably, the conditional formula -2.31≦f1 / f≦-1.23 is satisfied.

[0029] When the radius of curvature of the object side surface of the first lens L1 is R1 and the radius of curvature of the image side surface of the first lens L1 is R2, the conditional expression 0.52≦(R1+R2) / (R1-R2)≦2.29 is satisfied, and the shape of the first lens L1 is reasonably controlled, so that the first lens L1 can effectively correct the system spherical aberration. Preferably, the conditional expression 0.83≦(R1+R2) / (R1-R2)≦1.83 is satisfied.

[0030] When the axial thickness of the first lens L1 is d1 and the optical length of the imaging optical lens 10 is TTL, the condition 0.02≦d1 / TTL≦0.16 is satisfied, which is advantageous for realizing compactness within the range of the condition. Preferably, the condition 0.03≦d1 / TTL≦0.13 is satisfied.

[0031] In this embodiment, the object side surface of the second lens L2 is a paraxially concave surface, and the image side surface of the second lens L2 is a paraxially 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 situations.

[0032] When the focal length of the imaging optical lens 10 is f and the focal length of the second lens L2 is f2, the conditional expression -7.07≦f2 / f≦-1.27 is satisfied, and the negative refractive power of the second lens L2 is controlled within a reasonable range, which is advantageous for correcting aberrations of the optical system. Preferably, the conditional expression -4.42≦f2 / f≦-1.59 is satisfied.

[0033] 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, the conditional formula -7.70≦(R3+R4) / (R3-R4)≦-1.12 is satisfied, which defines the shape of the second lens L2 and is advantageous for correcting off-axis aberrations and the like as ultra-thin and wide-angle lenses are developed within this range. Preferably, the conditional formula -4.81≦(R3+R4) / (R3-R4)≦-1.40 is satisfied.

[0034] When the axial thickness of the second lens L2 is d3 and the optical length of the imaging optical lens 10 is TTL, the condition 0.02≦d3 / TTL≦0.09 is satisfied, which is advantageous for realizing compactness within the range of the condition. Preferably, the condition 0.04≦d3 / TTL≦0.07 is satisfied.

[0035] 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 situations.

[0036] When the radius of curvature of the object side surface of the third lens L3 is R5 and the radius of curvature of the image side surface of the third lens L3 is R6, the conditional expression -0.44≦(R5+R6) / (R5-R6)≦-0.05 is satisfied, which defines the shape of the third lens L3, and within this range, the degree of deflection of light rays can be reduced and chromatic aberration can be effectively corrected. Preferably, the conditional expression -0.28≦(R5+R6) / (R5-R6)≦-0.07 is satisfied.

[0037] When the axial thickness of the third lens L3 is d5 and the optical length of the imaging optical lens 10 is TTL, the condition 0.03≦d5 / TTL≦0.12 is satisfied, and within the range of the condition, it is advantageous for realizing compactness. Preferably, 0.05≦d5 / TTL≦0.10 is satisfied.

[0038] In this embodiment, the object side surface of the fourth lens L4 is a paraxially convex surface, and the image side surface of the fourth lens L4 is a paraxially convex surface, and the fourth lens L4 has a positive 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 situations.

[0039] When the focal length of the imaging optical lens 10 is f and the focal length of the fourth lens L4 is f4, the condition 0.53≦f4 / f≦1.86 is satisfied, and the system has excellent imaging quality and low sensitivity due to the reasonable distribution of refractive power, and preferably satisfies 0.85≦f4 / f≦1.49.

[0040] When the radius of curvature of the center of the object side surface of the fourth lens L4 is R7 and the radius of curvature of the center of the image side surface of the fourth lens L4 is R8, the conditional expression 0.20≦(R7+R8) / (R7-R8)≦0.69 is satisfied, which defines the shape of the fourth lens L4, and within this range, it is advantageous for correcting aberrations of off-axis angles of view, etc., as the trend toward ultra-thin and long focal lengths progresses. Preferably, 0.32≦(R7+R8) / (R7-R8)≦0.55 is satisfied.

[0041] When the axial thickness of the fourth lens L4 is d7 and the optical length of the imaging optical lens 10 is TTL, the condition 0.06≦d7 / TTL≦0.20 is satisfied, and within the range of the condition, it is advantageous for realizing compactness. Preferably, 0.09≦d7 / TTL≦0.16 is satisfied.

[0042] In this embodiment, the object side surface of the fifth lens L5 is a paraxially concave surface, the image side surface of the fifth lens L5 is a paraxially concave surface, and the fifth lens L5 has a negative 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 situations.

[0043] When the focal length of the imaging optical lens 10 is f and the focal length of the fifth lens L5 is f5, the condition -3.15≦f5 / f≦-0.78 is satisfied, and the system has excellent imaging quality and low sensitivity due to the reasonable distribution of refractive power, and preferably satisfies -1.97≦f5 / f≦-0.97.

[0044] 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 -1.73≦(R9+R10) / (R9-R10)≦-0.51 is satisfied, which defines the shape of the fifth lens L5 and is advantageous for correcting off-axis angle of view aberrations and the like as the trend toward ultra-thin and wide-angle lenses progresses. Preferably, the conditional expression -1.08≦(R9+R10) / (R9-R10)≦-0.64 is satisfied.

[0045] When the axial thickness of the fifth lens L5 is d9 and the optical length of the imaging optical lens 10 is TTL, 0.02≦d9 / TTL≦0.11 is satisfied, and within the range of the conditional formula, it is advantageous for realizing compactness. Preferably, 0.04≦d9 / TTL≦0.09 is satisfied.

[0046] In this embodiment, the sixth lens L6 has a paraxially convex object side surface and a paraxially concave image side surface, and has positive refractive power. In other alternative embodiments, the object side surface and the image side surface of the sixth lens L6 may be arranged in other concave-convex distribution situations.

[0047] When the focal length of the imaging optical lens 10 is f and the focal length of the sixth lens L6 is f6, the relationship 1.48≦f6 / f≦6.86 is satisfied, and the system has excellent imaging quality and low sensitivity due to the reasonable distribution of refractive power, and preferably the relationship 2.37≦f6 / f≦5.49 is satisfied.

[0048] When the axial thickness of the sixth lens L6 is d11 and the optical length of the imaging optical lens 10 is TTL, the condition 0.06≦d11 / TTL≦0.22 is satisfied, and within the range of the condition, it is advantageous for realizing a compact size. Preferably, 0.10≦d11 / TTL≦0.18 is satisfied.

[0049] In this embodiment, when the angle of view of the imaging optical lens is taken as FOV, the conditional expression FOV≧120° is satisfied, and a super wide angle is realized.

[0050] In this embodiment, the aperture value FNO of the imaging optical lens 10 is 2.40 or less, which is a large aperture and provides excellent imaging performance of the imaging optical lens.

[0051] The imaging optical lens 10 has good optical performance and can meet the design requirements of large aperture, ultra-wide angle, and compactness. Based on the characteristics of the imaging optical lens 10, the imaging optical lens 10 is particularly suitable for mobile phone imaging lens assemblies composed of imaging elements such as CCD and CMOS for high pixels, WEB imaging lenses, and imaging lenses for drones.

[0052] The imaging optical lens 10 of the present invention will be described below using examples. Symbols used in each example are as follows. The units of focal length, axial distance, central radius of curvature, axial thickness, inflection point position, and stationary point position are mm.

[0053] TTL is the optical length (the axial distance from the object side surface of the first lens L1 to the image plane Si) and is expressed in mm. Aperture number FNO is the ratio of the effective focal length of an imaging optical lens to the entrance pupil diameter.

[0054] Preferably, an inflection point and / or a stationary point may be further set on the object side and / or image side of the lens to meet the demand for high quality imaging, and a specific embodiment is given below.

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

[0056] [Table 1]

[0057] The meaning of each symbol in the table is as follows: S1: Aperture R: Radius of curvature at the center of the optical surface R0: Radius of curvature of the center of the protective glass PG on the object side R01: Radius of curvature of the center of the image side of the protective glass PG 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 curvature radius of the object side of the optical filter GF R14: Radius of curvature of the center of the image side of the optical filter GF T0: Axial thickness of protective glass PG T01: Axial distance from the image side of the protective glass PG to the object side of the first lens L1 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: The axial distance from the image side surface of the sixth lens L6 to the object side surface of the optical filter GF d13: On-axis thickness of optical filter GF d14: Axial distance from the image side of the optical filter GF to the image plane Si nd: Refractive index of d line (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 ndg1: refractive index of the d line of the protective glass PG ndg2: 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 vg1: Abbe number of protective glass PG vg2: Abbe number of the optical filter GF

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

[0059] [Table 2]

[0060] For convenience, the aspheric surface of each lens surface is expressed by the following formula (25): However, the present invention is not particularly limited to the aspheric polynomial of formula (25).

[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 +A18r18 +A20r 20 (twenty five)

[0062] where k is a conic coefficient, A4, A6, A8, A10, A12, A14, A16, A18, and A20 are aspheric coefficients, c is the curvature at the center of the optical surface, r is the perpendicular distance between a point on the aspheric curve and the optical axis, and z is the aspheric depth (the perpendicular distance between a point on the aspheric surface that is at a distance r from the optical axis and a cross section tangent to the vertex of the aspheric surface on the optical axis).

[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. Here, P1R1 and P1R2 indicate the object side surface and image side surface of the first lens L1, P2R1 and P2R2 indicate the object side surface and image side surface of the second lens L2, P3R1 and P3R2 indicate the object side surface and image side surface of the third lens L3, P4R1 and P4R2 indicate the object side surface and image side surface of the fourth lens L4, P5R1 and P5R2 indicate the object side surface and image side surface of the fifth lens L5, and P6R1 and P6R2 indicate the object side surface and 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 located 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 .

[0064] [Table 3]

[0065] [Table 4]

[0066] Fig. 2 and Fig. 3 are schematic diagrams showing the axial chromatic aberration and lateral chromatic aberration of light having wavelengths of 650 nm, 610 nm, 555 nm, 510 nm, and 470 nm after passing through the imaging optical lens 10 according to the first embodiment. Fig. 4 is a schematic diagram showing the field curvature and distortion aberration of light having a wavelength of 555 nm after passing through the imaging optical lens 10 according to the first embodiment, where the field curvature S in Fig. 4 is the field curvature in the sagittal direction, and T is the field curvature in the tangential direction.

[0067] Table 29, which will be presented later, shows various numerical values ​​in each embodiment and values ​​corresponding to parameters defined by conditional expressions.

[0068] As shown in Table 29, the first embodiment satisfies each of the conditional expressions.

[0069] In this embodiment, the imaging optical lens 10 has an entrance pupil diameter ENPD of 1.237 mm, a full field of view image height IH of 3.930 mm, and a diagonal field angle FOV of 150.62°. The imaging optical lens 10 satisfies the design requirements of a large aperture, an ultra-wide angle, and compactness, and its on-axis and off-axis chromatic aberrations are sufficiently corrected, and it has excellent optical characteristics.

[0070] 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, so only the differences will be described below.

[0071] Shown in FIG. 5 is an imaging optical lens 20 according to a second embodiment of the present invention.

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

[0073] [Table 5]

[0074] Table 6 shows the aspheric 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 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.

[0077] [Table 7]

[0078] [Table 8]

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

[0080] As shown in Table 29, the second embodiment satisfies each of the conditional expressions.

[0081] In this embodiment, the imaging optical lens 20 has an entrance pupil diameter ENPD of 1.464 mm, a full field of view image height IH of 3.930 mm, and a diagonal field angle FOV of 121.88°. The imaging optical lens 20 satisfies the design requirements of a large aperture, an ultra-wide angle, and compactness, has its on-axis and off-axis chromatic aberrations sufficiently corrected, and has excellent optical characteristics.

[0082] 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, so only the differences will be described below.

[0083] Shown in FIG. 9 is an imaging optical lens 30 according to a third embodiment of the present invention.

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

[0085] [Table 9]

[0086] Table 10 shows the aspheric 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 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.

[0089] [Table 11]

[0090] [Table 12]

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

[0092] As shown in Table 29, the third embodiment satisfies each of the conditional expressions.

[0093] In this embodiment, the imaging optical lens 30 has an entrance pupil diameter ENPD of 1.335 mm, a full field of view image height IH of 3.930 mm, and a diagonal field angle FOV of 136.60°. The imaging optical lens 30 satisfies the design requirements of a large aperture, an ultra-wide angle, and compactness, has its on-axis and off-axis chromatic aberrations sufficiently corrected, and has excellent optical characteristics.

[0094] (Fourth embodiment) The fourth embodiment is basically the same as the first embodiment, and the symbols have the same meanings as in the first embodiment, so only the differences will be described below.

[0095] Shown in FIG. 13 is an imaging optical lens 40 according to a fourth embodiment of the present invention.

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

[0097] [Table 13]

[0098] Table 14 shows the aspheric 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 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.

[0101] [Table 15]

[0102] [Table 16]

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

[0104] As shown in Table 29, the fourth embodiment satisfies each of the conditional expressions.

[0105] In this embodiment, the imaging optical lens 40 has an entrance pupil diameter ENPD of 1.146 mm, a full field of view image height IH of 3.930 mm, and a diagonal field angle FOV of 159.64°. The imaging optical lens 40 satisfies the design requirements of a large aperture, an ultra-wide angle, and compactness, has its on-axis and off-axis chromatic aberrations sufficiently corrected, and has excellent optical characteristics.

[0106] 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, so only the differences will be described below.

[0107] Shown in FIG. 17 is an imaging optical lens 50 according to a fifth embodiment of the present invention.

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

[0109] [Table 17]

[0110] Table 18 shows the aspheric 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 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.

[0113] [Table 19]

[0114] [Table 20]

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

[0116] As shown in Table 29, the fifth embodiment satisfies each of the conditional expressions.

[0117] In this embodiment, the imaging optical lens 50 has an entrance pupil diameter ENPD of 1.191 mm, a full field of view image height IH of 3.930 mm, and a diagonal field angle FOV of 152.23°. The imaging optical lens 50 satisfies the design requirements of a large aperture, an ultra-wide angle, and compactness, has its on-axis and off-axis chromatic aberrations sufficiently corrected, and has excellent optical characteristics.

[0118] Sixth embodiment The sixth embodiment is basically the same as the first embodiment, and the symbols have the same meanings as in the first embodiment, so only the differences will be described below.

[0119] Shown in FIG. 21 is an imaging optical lens 60 according to a sixth embodiment of the present invention.

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

[0121] [Table 21]

[0122] Table 22 shows the aspheric data of each lens in the imaging optical lens 60 according to the sixth embodiment of the present invention.

[0123] [Table 22]

[0124] Tables 23 and 24 show design data for the inflection points and stationary points of each lens in the imaging optical lens 60 according to the sixth embodiment of the present invention.

[0125] [Table 23]

[0126] [Table 24]

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

[0128] As shown in Table 29, the sixth embodiment satisfies each of the conditional expressions.

[0129] In this embodiment, the imaging optical lens 60 has an entrance pupil diameter ENPD of 1.111 mm, a full field of view image height IH of 3.930 mm, and a diagonal field angle FOV of 158.56°. The imaging optical lens 60 satisfies the design requirements of a large aperture, an ultra-wide angle, and compactness, and its on-axis and off-axis chromatic aberrations are sufficiently corrected, and it has excellent optical characteristics.

[0130] (Comparative embodiment) The meanings of the symbols in the comparative embodiment are the same as those in the first embodiment, so only the differences are shown below.

[0131] FIG. 25 shows an imaging optical lens 70 according to a comparative embodiment.

[0132] Tables 25 and 26 show design data for the imaging optical lens 70 according to the comparative embodiment.

[0133] [Table 25]

[0134] Table 26 shows the aspheric data of each lens in the imaging optical lens 70 according to the comparative embodiment.

[0135] [Table 26]

[0136] Tables 27 and 28 show the design data of the inflection points and stationary points of each lens in the imaging optical lens 70 according to the comparative embodiment.

[0137] [Table 27]

[0138] [Table 28]

[0139] Fig. 26 and Fig. 27 are schematic diagrams showing the axial chromatic aberration and the chromatic aberration of magnification after light having wavelengths of 650 nm, 610 nm, 555 nm, 510 nm, and 470 nm has passed through the imaging optical lens 70 according to the comparative embodiment. Fig. 28 is a schematic diagram showing the field curvature and the distortion aberration after light having wavelength of 555 nm has passed through the imaging optical lens 70 according to the comparative embodiment. The field curvature S in Fig. 28 is the field curvature in the sagittal direction, and T is the field curvature in the tangential direction.

[0140] In the following Table 29, numerical values ​​corresponding to each conditional expression in the comparative embodiment are listed according to the above conditional expressions. Apparently, the imaging optical lens 70 of the comparative embodiment does not satisfy the above conditional expression 1.30≦d10 / d9≦4.00.

[0141] In the comparative embodiment, the entrance pupil diameter ENPD of the imaging optical lens 70 is 1.215 mm, the full field of view image height IH is 3.930 mm, and the diagonal field of view FOV is 152.00°, and the imaging optical lens 70 does not satisfy the design requirements of large aperture, ultra-wide angle, and compact size.

[0142] [Table 29]

[0143] As will be understood by those skilled in the art, the above-described embodiments are specific embodiments for realizing the present invention, and in actual application, various changes in form and details are possible without departing from the spirit and scope of the present invention.

Claims

1. 1. An imaging optical lens, comprising: the imaging optical lens is configured with, in order from the object side to the image side, a first lens having negative refractive power, a second lens having negative refractive power, a third lens having positive refractive power, a fourth lens having positive refractive power, a fifth lens having negative refractive power, and a sixth lens having positive refractive power, the first lens being made of a glass material, and the third lens being made of a glass material; an imaging optical lens satisfying the following conditional expressions (1) to (5): a refractive index of the third lens is n3, a focal length of the first lens is f1, a focal length of the second lens is f2, an axial thickness of the fifth lens is d9, an axial distance from the image side surface of the fifth lens to the object side surface of the sixth lens is d10, a central radius of curvature of the object side surface of the second lens is R3, a central radius of curvature of the image side surface of the second lens is R4, an optical length of the imaging optical lens is TTL, an image height of the imaging optical lens is IH, and an angle of view of the imaging optical lens is FOV. n3≧1.70 (1) 1.00≦f2 / f1≦2.00 (2) 1.30≦d10 / d9≦4.00 (3) 1.70≦R4 / R3≦4.00 (4) 0.02≦TTL / (IH×FOV)≦0.03 (5)

2. 2. The imaging optical lens according to claim 1, wherein 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, the following conditional expression (6) is satisfied: -3.50≦(R11+R12) / (R11-R12)≦-1.30 (6)

3. 2. The imaging optical lens according to claim 1, wherein the following conditional expression (7) is satisfied, where f is a focal length of the imaging optical lens and f3 is a focal length of the third lens: 1.10≦f3 / f≦1.50 (7)

4. 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 concave surface, 2. The imaging optical lens according to claim 1, wherein the imaging optical lens satisfies the following conditional expressions (8) to (10), where f is a focal length of the imaging optical lens, R1 is a central radius of curvature of the object side surface of the first lens, R2 is a central radius of curvature of the image side surface of the first lens, and d1 is an axial thickness of the first lens. −3.69≦f1 / f≦−0.98 (8) 0.52≦(R1+R2) / (R1-R2)≦2.29 (9) 0.02≦d1 / TTL≦0.16 (10)

5. 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 imaging optical lens according to claim 1, wherein the imaging optical lens satisfies the following conditional expressions (11) to (13), where f is a focal length of the imaging optical lens and d3 is an axial thickness of the second lens: −7.07≦f2 / f≦−1.27 (11) -7.70≦(R3+R4) / (R3-R4)≦-1.12 (12) 0.02≦d3 / TTL≦0.09 (13)

6. 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 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 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, the following conditional expressions (14) and (15) are satisfied: -0.44≦(R5+R6) / (R5-R6)≦-0.05 (14) 0.03≦d5 / TTL≦0.12 (15)

7. an object side surface of the fourth lens is a paraxially convex surface, and an image side surface of the fourth 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 (16) to (18), 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. 0.53≦f4 / f≦1.86 (16) 0.20≦(R7+R8) / (R7-R8)≦0.69 (17) 0.06≦d7 / TTL≦0.20 (18)

8. an object side surface of the fifth lens is a paraxially concave surface, and an image side surface of the fifth 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 (19) to (21): −3.15≦f5 / f≦−0.78 (19) -1.73≦(R9+R10) / (R9-R10)≦-0.51 (20) 0.02≦d9 / TTL≦0.11 (21)

9. 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, 2. The imaging optical lens according to claim 1, wherein the imaging optical lens satisfies the following conditional expressions (22) and (23), where f is a focal length of the imaging optical lens, f is a focal length of the sixth lens, and d is an axial thickness of the sixth lens: 1.48≦f6 / f≦6.86 (22) 0.06≦d11 / TTL≦0.22 (23)

10. 2. The imaging optical lens according to claim 1, wherein the following conditional expression (24) is satisfied when the angle of view of the imaging optical lens is taken as FOV: FOV≧120° (24)

Images