Image capturing optical lens
The seven-lens optical lens design addresses the need for compact imaging lenses with wide angles and aberration correction, achieving high optical performance and large apertures for mobile and fisheye applications.
Patent Information
- Application Number
- JP2024091005
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2024-02-06
- Filing Date
- 2024-06-04
- Publication Date
- 2025-08-19
- Estimated Expiration
- 2044-06-04
AI Technical Summary
There is a demand for compact imaging optical lenses with excellent optical performance, wide angle, and sufficient aberration correction, particularly for mobile devices and imaging devices, which existing technologies have not adequately addressed.
An imaging optical lens design comprising seven lenses with specific refractive indices, distances, and curvatures, including glass and resin materials, to achieve a large aperture, ultra-thinness, and wide angle, with optimized aberration correction.
The lens design provides excellent optical performance with a wide angle and large aperture, suitable for mobile imaging and fisheye applications, while maintaining ultra-thinness and effective aberration correction.
Smart Images

Figure 2025121349000001_ABST
Abstract
Description
[Technical Field]
[0001] The present invention relates to the field of optical lenses, and more particularly to an imaging optical lens that can be applied to mobile terminal devices such as smartphones, digital cameras, and drones, as well as imaging devices such as surveillance cameras and PC cameras. [Background technology]
[0002] In recent years, the rise of various smart devices has led to an increasing demand for compact imaging optical lenses. As the pixel size of photosensitive elements has become smaller, modern electronic products tend to be more functional, thinner, lighter, and more portable, resulting in the market trend toward compact imaging optical lenses with excellent image quality. To achieve better image quality, multi-lens structures are increasingly adopted. Furthermore, with technological developments and increasingly diverse user needs, the pixel area of photosensitive elements has been shrinking, and the demands for system imaging quality have continued to rise. As a result, seven-lens structures have gradually emerged in lens design. There is a demand for fisheye wide-angle imaging lenses that offer excellent optical performance, a small volume, and sufficient aberration correction. Summary of the Invention
[0003] In view of the above problems, an object of the present invention is to provide an imaging optical lens that has excellent optical performance and can satisfy design requirements for a large aperture, ultra-thinness, and wide angle.
[0004] In order to solve the above technical problems, according to an aspect of the present invention, there is provided an imaging optical lens, comprising 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 positive refractive power, a sixth lens having negative refractive power, and a seventh lens having positive refractive power, which are arranged in this order from an object side to an image side, wherein the refractive index of the first lens is n1, and the distance on the optical axis between the image side surface of the third lens and the object side surface of the fourth lens is d6; is provided an imaging optical lens that satisfies the above relational expressions: a total optical length of the imaging optical lens is TTL, an angle of view of the imaging optical lens is FOV, a focal length of the imaging optical lens is f, an image height of a full field of view of the imaging optical lens is IH, a central radius of curvature of the object-side surface of the seventh lens is R13, a central radius of curvature of the image-forming side surface of the seventh lens is R14, and n1≧1.70, 0.06≦d6 / TTL≦0.08, 100.00≦(FOV×f) / IH≦130.00, and −1.00≦(R13+R14) / (R13−R14)≦−0.70.
[0005] Preferably, the Abbe number of the fifth lens is v5, and the Abbe number of the sixth lens is v6, satisfying the following relational expression: v5-v6≧35.00.
[0006] Preferably, the thickness of the third lens on the optical axis is d5, and the thickness of the fourth lens on the optical axis is d7, satisfying the following relational expression: 0.35≦d5 / d7≦0.70.
[0007] Preferably, the following relationship is satisfied: 6.50≦TTL / f≦8.50.
[0008] Preferably, a portion of the object-side surface of the first lens close to the optical axis is a convex surface, a portion of the image-side surface of the first lens close to the optical axis is a concave surface, the focal length of the first lens is f1, the central curvature of the object-side surface of the first lens is R1, the central curvature of the image-side surface of the first lens is R2, and the thickness of the first lens on the optical axis is d1, satisfying the following relations: -7.88≦f1 / f≦-1.93, 0.96≦(R1+R2) / (R1-R2)≦3.01, 0.02≦d1 / TTL≦0.14.
[0009] Preferably, a portion of the object-side surface of the second lens close to the optical axis is a convex surface, a portion of the image-side surface of the second lens close to the optical axis is a concave surface, the focal length of the second lens is f2, the central curvature of the object-side surface of the second lens is R3, the central curvature of the image-side surface of the second lens is R4, and the thickness of the second lens on the optical axis is d3, satisfying the following relations: -8.54≦f2 / f≦-2.48, 2.23≦(R3+R4) / (R3-R4)≦7.55, and 0.02≦d3 / TTL≦0.06.
[0010] Preferably, a portion of the object-side surface of the third lens close to the optical axis is a convex surface, a portion of the image-side surface of the third lens close to the optical axis is a concave surface, the focal length of the third lens is f3, the central curvature of the object-side surface of the third lens is R5, the central curvature of the image-side surface of the third lens is R6, and the thickness of the third lens on the optical axis is d5, satisfying the following relations: 3.23≦f3 / f≦13.49, −7.02≦(R5+R6) / (R5−R6)≦−2.07, 0.03≦d5 / TTL≦0.12.
[0011] Preferably, a portion of the object-side surface of the fourth lens close to the optical axis is concave, a portion of the image-side surface of the fourth lens close to the optical axis is convex, the focal length of the fourth lens is f4, the central curvature of the object-side surface of the fourth lens is R7, the central curvature of the image-side surface of the fourth lens is R8, and the thickness of the fourth lens on the optical axis is d7, satisfying the following relations: 1.03≦f4 / f≦3.77, 0.62≦(R7+R8) / (R7−R8)≦1.88, 0.06≦d7 / TTL≦0.22.
[0012] Preferably, a portion of the object-side surface of the fifth lens close to the optical axis is a convex surface, a portion of the image-side surface of the fifth lens close to the optical axis is a convex surface, the focal length of the fifth lens is f5, the central curvature of the object-side surface of the fifth lens is R9, the central curvature of the image-side surface of the fifth lens is R10, and the thickness of the fifth lens on the optical axis is d9, satisfying the following relations: 1.22≦f5 / f≦4.21, -0.15≦(R9+R10) / (R9−R10)≦0.08, 0.08≦d9 / TTL≦0.25.
[0013] Preferably, the first lens is made of a glass material, and the fourth lens is made of a glass material.
[0014] The present invention provides the following advantages: The imaging optical lens according to the present invention has excellent optical properties, a large aperture, an ultra-thin shape, and a wide angle of view, and is particularly suitable for use in mobile imaging lens assemblies, web imaging lenses, and fisheye imaging lenses for drones, which are configured with imaging elements such as high-pixel CCDs and CMOSs. [Brief explanation of the drawings]
[0015] In order to more clearly describe the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly described below. However, the drawings in the following description only relate to a part of the embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any creative efforts.
[0016] [Figure 1] 1 is a schematic diagram showing the structure of an imaging optical lens according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a schematic diagram of axial chromatic aberration of the imaging optical lens shown in FIG. [Figure 3] FIG. 2 is a schematic diagram of chromatic aberration of magnification of the imaging optical lens shown in FIG. [Figure 4] 2 is a schematic diagram of field curvature and distortion of the imaging optical lens shown in FIG. 1. [Figure 5] FIG. 4 is a schematic diagram showing the structure of an imaging optical lens according to a second embodiment of the present invention. [Figure 6] FIG. 6 is a schematic diagram of axial chromatic aberration of the imaging optical lens shown in FIG. 5. [Figure 7] FIG. 6 is a schematic diagram of chromatic aberration of magnification of the imaging optical lens shown in FIG. 5. [Figure 8] 6A and 6B are schematic diagrams of field curvature and distortion of the imaging optical lens shown in FIG. 5. [Figure 9] FIG. 10 is a schematic diagram showing the structure of an imaging optical lens according to a third embodiment of the present invention. [Figure 10] FIG. 10 is a schematic diagram of axial chromatic aberration of the imaging optical lens shown in FIG. [Figure 11] FIG. 10 is a schematic diagram of chromatic aberration of magnification of the imaging optical lens shown in FIG. [Figure 12] 10A and 10B are schematic diagrams of field curvature and distortion of the imaging optical lens shown in FIG. [Figure 13] FIG. 10 is a schematic diagram showing the structure of an imaging optical lens according to a fourth embodiment of the present invention. [Figure 14] FIG. 14 is a schematic diagram of axial chromatic aberration of the imaging optical lens shown in FIG. [Figure 15] FIG. 14 is a schematic diagram of chromatic aberration of magnification of the imaging optical lens shown in FIG. [Figure 16] 14A and 14B are schematic diagrams of field curvature and distortion of the imaging optical lens shown in FIG. 13. [Figure 17] FIG. 10 is a schematic diagram showing the structure of an imaging optical lens according to a comparative embodiment. [Figure 18] FIG. 18 is a schematic diagram of axial chromatic aberration of the imaging optical lens shown in FIG. [Figure 19] FIG. 18 is a schematic diagram of chromatic aberration of magnification of the imaging optical lens shown in FIG. [Figure 20] 18A and 18B are schematic diagrams of field curvature and distortion of the imaging optical lens shown in FIG. 17. DETAILED DESCRIPTION OF THE INVENTION
[0017] In order to clarify the objectives, technical solutions, and advantages of the present invention, the following detailed description of the embodiments of the present invention is provided in conjunction with the accompanying drawings. However, those skilled in the art will understand that many technical details are presented in the embodiments of the present invention to help readers better understand the present invention. However, the technical solutions claimed for the protection of the present invention can be realized without these technical details or various changes and modifications based on the following embodiments.
[0018] With reference to FIGS. 1 to 16, imaging optical lenses 10, 20, 30, and 40 are provided according to the present invention. FIGS. 1, 5, 9, and 13 show imaging optical lenses 10, 20, 30, and 40 according to the present invention. Each of the imaging optical lenses 10, 20, 30, and 40 includes a total of seven lenses. Specifically, the imaging optical lenses 10, 20, 30, and 40 include, in order from the object side to the image side, a first lens L1, a second lens L2, a third lens L3, a diaphragm S1, a fourth lens L4, a fifth lens L5, 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.
[0019] In this embodiment, the first lens L1 is made of glass, the second lens L2 is made of resin, the third lens L3 is made of resin, the fourth lens L4 is made of glass, the fifth lens L5 is made of resin, the sixth lens L6 is made of resin, and the seventh lens L7 is made of resin. Each lens may be made of other materials.
[0020] The refractive index of the first lens L1 is defined as n1, and the relational expression n1≧1.70 is satisfied. In this way, the refractive index of the first lens L1 is specified. It is preferable that the first lens L1 is made of a high refractive index material. This allows for a reduction in the front end aperture diameter of the imaging optical lens and an improvement in the imaging mass.
[0021] The distance on the optical axis between the image-forming side of the third lens L3 and the object-side of the fourth lens is d6, and the total optical length of the imaging optical lens is TTL, satisfying the relationship 0.06≦d6 / TTL≦0.08. In this way, the proportional value of the distance between the lenses located on both sides of the aperture S1 and the total optical length is specified. Because the distance between the lenses located on both sides of the aperture S1 is large, light rays near the aperture S1 can transition smoothly, improving the imaging mass.
[0022] The angle of view of the imaging optical lens is FOV, the focal length of the imaging optical lens is f, and the image height of the entire field of view of the imaging optical lens is IH, and the following relational expression is satisfied: 100.00≦(FOV×f) / IH≦130.00. This achieves both an ultra-wide angle of view and a long focal length, enabling imaging at medium to long distances.
[0023] The radius of curvature of the center of the object-side surface of the seventh lens L7 is R13, and the radius of curvature of the center of the image-forming side surface of the seventh lens L7 is R14, and the relationship -1.00≦(R13+R14) / (R13-R14)≦-0.70 is satisfied. By specifying the shape of the seventh lens L7 so that the above relationship is satisfied, the amount of field curvature of the system can be effectively balanced, and the shift amount of field curvature in the central field of view can be reduced to less than 0.01 mm. Here, the system is an imaging optical lens.
[0024] The Abbe number of the fifth lens L5 is v5, and the Abbe number of the sixth lens L6 is v6, and the relationship v5-v6≧35.00 is satisfied. In this way, by specifying the difference in Abbe numbers between the fifth lens L5 and the sixth lens L6 so that the above relationship is satisfied, it is possible to effectively distribute the material attributes and effectively correct chromatic aberration so that the relationship chromatic aberration |LC|≦12 μm is satisfied.
[0025] The on-axis thickness of the third lens L3 is d5, and the on-axis thickness of the fourth lens L4 is d7, which satisfy the relationship 0.35≦d5 / d7≦0.70. In this way, by specifying the proportional value between the on-axis thickness of the third lens L3 and the on-axis thickness of the fourth lens L4 so that the above relationship is satisfied, the total optical length of the system can be reduced.
[0026] The telephoto ratio is specified by the total optical length TTL of the imaging optical lens and the focal length f of the imaging optical lens satisfying the relational expression 6.50≦TTL / f≦8.50. When TTL / f is equal to or less than the upper limit of the relational expression, it is possible to control the reduction of the total optical length of the imaging optical lens, making it easier to miniaturize the imaging optical lens. On the other hand, when TTL / f is equal to or more than the lower limit of the relational expression, it is easy to correct distortion aberration and axial chromatic aberration, making it possible to maintain good optical performance of the imaging optical lens.
[0027] When the above-mentioned relational expressions are satisfied, the imaging optical lenses 10, 20, 30, and 40 have excellent optical performance and can satisfy the design requirements for a large aperture and a wide angle of view. These characteristics of the imaging optical lenses 10, 20, 30, and 40 make them suitable for use in mobile imaging lens assemblies, web imaging lenses, and fisheye imaging lenses for drones, which are particularly configured with imaging elements such as high-pixel CCDs and CMOSs.
[0028] Based on the above relational expressions and realizable functions, the characteristics of each lens will be described in detail.
[0029] The object side surface of the first lens L1 near the optical axis is a convex surface, and the image side surface of the first lens L1 near the optical axis is a concave surface, and the first lens L1 has negative refractive power. The object side surface and the image side surface of the first lens L1 may have other concave or convex distributions.
[0030] The proportional value between the negative refractive power of the first lens L1 and the overall focal length of the imaging optical lens is specified by satisfying the relational expression -7.88≦f1 / f≦-1.93, where f is the focal length of the imaging optical lens and f1 is the focal length of the first lens L1. When this relational expression is satisfied, the first lens L1 has an appropriate negative refractive power, which reduces system aberrations and enables the imaging optical lens to be made ultra-thin and have a wide angle of view. It is also preferable to satisfy the relational expression -4.92≦f1 / f≦-2.41.
[0031] The central curvature of the object-side surface of the first lens L1 is R1, and the central curvature of the image-side surface of the first lens L1 is R2. By satisfying the relationship 0.96≦(R1+R2) / (R1-R2)≦3.01, the shape of the first lens L1 can be reasonably controlled, and the first lens L1 can effectively correct the spherical aberration of the system. It is preferable that the relationship 1.53≦(R1+R2) / (R1-R2)≦2.41 be satisfied.
[0032] The thickness of the first lens L1 on the optical axis is d1, and the total optical length of the imaging optical lens is TTL, and the relational expression 0.02≦d1 / TTL≦0.14 is satisfied. When the above relational expression is satisfied, the imaging optical lens can be made ultra-thin. It is preferable that the relational expression 0.03≦d1 / TTL≦0.11 is satisfied.
[0033] The object side surface of the second lens L2 near the optical axis is a convex surface, and the image side surface of the second lens L2 near the optical axis is a concave surface, and the second lens L2 has negative refractive power. The object side surface and the image side surface of the second lens L2 may be provided with other concave or convex distributions.
[0034] If the focal length of the imaging optical lens is f and the focal length of the second lens L2 is f2, the aberrations of the system can be corrected by satisfying the relational expression -8.54≦f2 / f≦-2.48 and controlling the negative power of the second lens L2 within a reasonable range. It is preferable to satisfy the relation -5.34≦f2 / f≦-3.10.
[0035] The shape of the second lens L2 can be specified by satisfying the relational expression 2.23≦(R3+R4) / (R3-R4)≦7.55, where R3 is the central curvature of the object-side surface of the second lens L2 and R4 is the central curvature of the image-forming side surface of the second lens L2. When this relational expression is satisfied, axial chromatic aberration can be corrected as imaging optical lenses become ultra-thin and have a wide angle of view. It is also preferable to satisfy the relational expression 3.57≦(R3+R4) / (R3-R4)≦6.04.
[0036] The thickness of the second lens L2 on the optical axis is d3, and the total optical length of the imaging optical lens is TTL, which satisfies the relational expression 0.02≦d3 / TTL≦0.06. When this relational expression is satisfied, the imaging optical lens can be made ultra-thin. It is also preferable that the relational expression 0.03≦d3 / TTL≦0.05 is satisfied.
[0037] The object side surface of the third lens L3 near the optical axis is a convex surface, and the image side surface of the third lens L3 near the optical axis is a concave surface, and the third lens L3 has positive refractive power. The object side surface and the image side surface of the third lens L3 may have other concave or convex distributions.
[0038] The focal length of the imaging optical lens is f, and the focal length of the third lens L3 is f3, and the relationship 3.23≦f3 / f≦13.49 is satisfied. By reasonably distributing the power of the third lens L3, the system can have excellent imaging quality and low sensitivity, and preferably satisfying 5.16≦f3 / f≦10.80.
[0039] The central curvature of the object-side surface of the third lens L3 is R5, and the central curvature of the image-side surface of the third lens L3 is R6. By satisfying the relationship -7.02≦(R5+R6) / (R5-R6)≦-2.07, the shape of the third lens L3 can be specified, making it easier to mold the third lens L3. When this relationship is satisfied, the degree of refraction of light rays passing through the third lens L3 can be reduced, effectively reducing aberrations. It is preferable to satisfy the relationship -4.39≦(R5+R6) / (R5-R6)≦-2.59.
[0040] The thickness of the third lens L3 on the optical axis is d5, and the total optical length of the imaging optical lens is TTL, satisfying the relational expression 0.03≦d5 / TTL≦0.12. When this relational expression is satisfied, the imaging optical lens can be made ultra-thin. It is also preferable that the relational expression 0.04≦d5 / TTL≦0.10 is satisfied.
[0041] The fourth lens L4 has a concave surface on the object side close to the optical axis and a convex surface on the image side close to the optical axis, and has positive refractive power. The object side and image side surfaces of the fourth lens L4 may have other concave or convex distributions.
[0042] The focal length of the imaging optical lens is f, the focal length of the fourth lens L4 is f4, and the relationship 1.03≦f4 / f≦3.77 is satisfied. By reasonably distributing the power of the fourth lens L4, the system can have excellent imaging quality and low sensitivity, and it is preferable to satisfy 1.65≦f4 / f≦3.01.
[0043] The shape of fourth lens L4 can be specified by defining the central curvature of the object-side surface of fourth lens L4 as R7 and the central curvature of the image-side surface of fourth lens L4 as R8, and satisfying the relational expression 0.62≦(R7+R8) / (R7-R8)≦1.88. When this relational expression is satisfied, chromatic aberrations at off-axis angles of view can be effectively corrected as imaging optical lenses become ultra-thin and have wide angles of view. It is also preferable to satisfy the relation 0.99≦(R7+R8) / (R7-R8)≦1.50.
[0044] The thickness of the fourth lens L4 on the optical axis is d7, and the total optical length of the imaging optical lens is TTL, which satisfies the relational expression 0.06≦d7 / TTL≦0.22. When this relational expression is satisfied, the imaging optical lens can be made ultra-thin. It is also preferable that the relational expression 0.09≦d7 / TTL≦0.18 is satisfied.
[0045] The fifth lens L5 has a convex surface on its object side near the optical axis, a convex surface on its image side near the optical axis, and a positive refractive power. The object side and image side surfaces of the fifth lens L5 may have other concave or convex distributions.
[0046] The focal length of the imaging optical lens is f, and the focal length of the fifth lens L5 is f5. The relationship 1.22≦f5 / f≦4.21 is satisfied, and the fifth lens L5 can effectively relax the ray angle of the imaging optical lenses 10, 20, 30, and 40, thereby reducing tolerance sensitivity. It is preferable that the relationship 1.95≦f5 / f≦3.37 is satisfied.
[0047] The shape of fifth lens L5 can be specified by satisfying the relational expression -0.15≦(R9+R10) / (R9-R10)≦0.08, where R9 is the central curvature of the object-side surface of fifth lens L5 and R10 is the central curvature of the image-forming side surface of fifth lens L5. When this relational expression is satisfied, chromatic aberrations at off-axis angles of view can be effectively corrected as imaging optical lenses become ultra-thin and have wide angles of view. It is also preferable to satisfy the relational expression -0.09≦(R9+R10) / (R9-R10)≦0.06.
[0048] The thickness of the fifth lens L5 on the optical axis is d9, and the total optical length of the imaging optical lens is TTL, which satisfies the relational expression 0.08≦d9 / TTL≦0.25. When this relational expression is satisfied, the imaging optical lens can be made ultra-thin. It is also preferable that the relational expression 0.12≦d9 / TTL≦0.20 is satisfied.
[0049] The sixth lens L6 has a concave surface on its object side near the optical axis, a concave surface on its image side near the optical axis, and a negative refractive power. The object side and image side surfaces of the sixth lens L6 may have other concave or convex distributions.
[0050] The focal length of the imaging optical lens is f, the focal length of the sixth lens L6 is f6, and the relationship -3.70≦f6 / f≦-1.00 is satisfied. By reasonably distributing the power of the sixth lens L6, the system can have excellent imaging quality and low sensitivity. It is preferable to satisfy the relationship -2.31≦f6 / f≦-1.25.
[0051] The shape of the sixth lens L6 can be specified by defining the central curvature of the object-side surface of the sixth lens L6 as R11 and the central curvature of the image-side surface of the sixth lens L6 as R12, and satisfying the relational expression 0.09≦(R11+R12) / (R11-R12)≦0.43. When this relational expression is satisfied, chromatic aberrations at off-axis angles of view can be effectively corrected as imaging optical lenses become ultra-thin and have wide angles of view. It is also preferable to satisfy the relational expression 0.14≦(R11+R12) / (R11-R12)≦0.34.
[0052] The thickness of the sixth lens L6 on the optical axis is d11, and the total optical length of the imaging optical lens is TTL, which satisfies the relational expression 0.02≦d11 / TTL≦0.09. When this relational expression is satisfied, the imaging optical lens can be made ultra-thin. It is also preferable that the relational expression 0.04≦d11 / TTL≦0.07 is satisfied.
[0053] The seventh lens L7 has a convex surface on the object side close to the optical axis, a convex surface on the image side close to the optical axis, and a positive refractive power. The object side and image side surfaces of the seventh lens L7 may have other concave or convex distributions.
[0054] The focal length of the imaging optical lens is f, the focal length of the seventh lens L7 is f7, and the relationship 0.91≦f7 / f≦3.00 is satisfied. By reasonably distributing the power of the seventh lens L7, the system can have excellent imaging quality and low sensitivity, and it is preferable to satisfy the relationship 1.46≦f7 / f≦2.40.
[0055] The shape of the seventh lens L7 can be specified by defining the central curvature of the object-side surface of the seventh lens L7 as R13 and the central curvature of the image-side surface of the seventh lens L7 as R14, and satisfying the relational expression -1.91≦(R13+R14) / (R13-R14)≦-0.47. When this relational expression is satisfied, chromatic aberrations at off-axis angles of view can be effectively corrected as imaging optical lenses become ultra-thin and have wide angles of view. It is also preferable to satisfy the relational expression -1.19≦(R13+R14) / (R13-R14)≦-0.59.
[0056] The thickness of the seventh lens L7 on the optical axis is d13, and the total optical length of the imaging optical lens is TTL, which satisfies the relational expression 0.06≦d13 / TTL≦0.18. When this relational expression is satisfied, the imaging optical lens can be made ultra-thin. It is also preferable that the relational expression 0.09≦d13 / TTL≦0.15 is satisfied.
[0057] The image height of the imaging optical lens is IH, the total optical length of the imaging optical lens is TTL, and by satisfying the relation TTL / IH≦4.79, the imaging optical lens can be made ultra-thin. It is preferable to satisfy TTL / IH≦4.66.
[0058] The field of view FOV of the imaging optical lens is 187.05° or more, so that the imaging optical lens can have a wide field of view.
[0059] The aperture value FNO (F-number) of the imaging optical lens is 1.43 or less, so that the imaging optical lens can have a large aperture, and the imaging performance of the imaging optical lens can be improved.
[0060] The imaging optical lens according to the present invention will be described below using examples. The symbols used in each example are as follows: focal length, axial distance, central radius of curvature, axial thickness, curvature point position, and stationary point position are all in mm.
[0061] TTL is the total optical length (the distance on the optical axis from the object side of the first lens L1 to the image plane Si) and is expressed in mm.
[0062] The aperture value FNO refers to the ratio of the effective focal length to the effective aperture of an imaging optical lens.
[0063] Preferably, the object side and / or image side of the lens may further be provided with curvature points and / or stationary points to meet the demand for high quality imaging, and specific embodiments are described below.
[0064] Below, the present invention will be described in detail using four embodiments, and one comparative embodiment will be presented to explain that the technical effects of the present invention cannot be obtained if the above-mentioned relationship is not satisfied.
[0065] (First embodiment) Tables 1 and 2 show design data for the imaging optical lens 10 according to the first embodiment of the present invention.
[0066] [Table 1]
[0067] The meaning of each symbol is as follows: S1: Aperture R: Radius of curvature at the center of the optical surface R1: Radius of curvature of the center of the object side of the first lens L1 R2: Radius of central curvature of the image-forming side of the first lens L1 R3: Radius of curvature of the center of the object side of the second lens L2 R4: Radius of central curvature of the image-forming side of the second lens L2 R5: Radius of curvature of the center of the object side of the third lens L3 R6: Radius of central curvature of the image-forming side of the third lens L3 R7: Radius of curvature of the center of the object side of the fourth lens L4 R8: Radius of central curvature of the image-forming side of the fourth lens L4 R9: Radius of curvature of the center of the object side of the fifth lens L5 R10: Radius of central curvature of the imaging side of the fifth lens L5 R11: Radius of curvature of the center of the object side of the sixth lens L6 R12: Radius of central curvature of the image-forming side of the sixth lens L6 R13: Radius of curvature of the center of the object side of the seventh lens L7 R14: Radius of central curvature of the image-forming side of the seventh lens L7 R15: Radius of curvature of the center of the object side of the optical filter GF R16: Radius of central curvature of the imaging side of the optical filter GF d: Lens thickness on the optical axis, distance between lenses on the optical axis d0: Distance on the optical axis from the aperture stop S1 to the object side of the first lens L1 d1: thickness of the first lens L1 on the optical axis d2: the distance on the optical axis from the image-forming side surface of the first lens L1 to the object-side surface of the second lens L2 d3: Thickness of the second lens L2 on the optical axis d4: The distance on the optical axis from the image-forming side of the second lens L2 to the object-side of the third lens L3 d5: Thickness of the third lens L3 on the optical axis d6: the distance on the optical axis from the image-forming side surface of the third lens L3 to the object-side surface of the fourth lens L4 d7: Thickness of the fourth lens L4 on the optical axis d8: the distance on the optical axis from the image-forming side surface of the fourth lens L4 to the object-side surface of the fifth lens L5 d9: Thickness of the fifth lens element L5 on the optical axis d10: the distance on the optical axis from the image-forming side surface of the fifth lens L5 to the object-side surface of the sixth lens L6 d11: Thickness of the sixth lens element L6 on the optical axis d12: the distance on the optical axis from the image-forming side surface of the sixth lens L6 to the object-side surface of the seventh lens L7 d13: Axial thickness of the seventh lens element L7 d14: The distance on the optical axis from the image-forming side surface of the seventh lens L7 to the object-side surface of the optical filter GF d15: Thickness of the optical filter GF on the optical axis d16: Distance on the optical axis from the imaging side of the optical filter GF to the imaging surface Si nd: Refractive index of the d-line (d-line is green light with a wavelength of 550 nm). 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 element L3 v4: Abbe number of the fourth lens element L4 v5: Abbe number of the fifth lens element L5 v6: Abbe number of the sixth lens element L6 v7: Abbe number of the seventh lens element L7 vg: Abbe number of the optical filter GF
[0068] Table 2 shows the aspheric surface data of each lens in the imaging optical lens 10 according to the first embodiment of the present invention.
[0069] [Table 2]
[0070] For convenience, the aspherical surface of each lens surface is assumed to be aspherical as shown in the following formula (1). However, the present invention is not limited to the form of the aspherical polynomial expressed by formula (1). z=(cr 2 ) / {1+[1-(k+1)(c 2 r 2 )] 1 / 2}+A4r 4 +A6r 6 +A8r 8 +A10r 10 +A12r 12 +A14r 14 +A16r 16 +A18r 18 +A20r 20 +A22r 22 +A24r 24 +A26r 26 +A28r 28 +A30r 30 (1)
[0071] Here, k is a conic coefficient, A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28, and A30 are aspheric coefficients, c is the curvature of the central location 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 a distance r from the optical axis and a tangent plane that is in contact with the vertex on the aspheric optical axis).
[0072] Tables 3 and 4 show design data for the curvature points and stationary points of each lens in the photographic optical lens 10 according to the first embodiment of the present invention. Here, P1R1 and P1R2 represent the object-side and image-side surfaces, respectively, of the first lens L1, P2R1 and P2R2 represent the object-side and image-side surfaces, respectively, of the second lens L2, P3R1 and P3R2 represent the object-side and image-side surfaces, respectively, of the third lens L3, P4R1 and P4R2 represent the object-side and image-side surfaces, respectively, of the fourth lens L4, P5R1 and P5R2 represent the object-side and image-side surfaces, respectively, of the fifth lens L5, P6R1 and P6R2 represent the object-side and image-side surfaces, respectively, of the sixth lens L6, and P7R1 and P7R2 represent the object-side and image-side surfaces, respectively, of the seventh lens L7. The data corresponding to the "curvature point position" column is the vertical distance from the curvature point provided on the surface of each lens to the optical axis 10 of the imaging optical lens. The data corresponding to the "stationary point position" column is the vertical distance from the stationary point provided on the surface of each lens to the optical axis 10 of the imaging optical lens.
[0073] [Table 3]
[0074] [Table 4]
[0075] 2 and 3 are schematic diagrams of the axial chromatic aberration and lateral chromatic aberration of light with 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 of the field curvature and distortion aberration of light with a wavelength of 555 nm after passing through the imaging optical lens 10 according to the first embodiment. In Fig. 4, the field curvature S is the field curvature in the sagittal direction, and T is the field curvature in the meridional direction.
[0076] In this embodiment, the imaging optical lens 10 has an effective aperture ENPD of 1.016 mm, a full-field image height IH of 2.733 mm, and a diagonal angle of view FOV of 206.00°. The imaging optical lens 10 satisfies the design requirements for a large aperture, a wide angle, and an ultra-thin design, has sufficient correction for chromatic aberrations on and off the optical axis, and has excellent optical properties.
[0077] (Second embodiment) The meanings of the symbols in the second embodiment are the same as those in the first embodiment.
[0078] FIG. 5 shows an imaging optical lens 20 according to a second embodiment of the present invention.
[0079] Tables 5 and 6 show design data for the imaging optical lens 20 according to the second embodiment of the present invention.
[0080] [Table 5]
[0081] Table 6 shows the aspheric surface data of each lens in the imaging optical lens 20 according to the second embodiment of the present invention.
[0082] [Table 6]
[0083] Tables 7 and 8 show the design data of the curvature points and stationary points of each lens in the imaging optical lens 20 according to the second embodiment of the present invention.
[0084] [Table 7]
[0085] [Table 8]
[0086] Figures 6 and 7 are schematic diagrams of the axial chromatic aberration and lateral chromatic aberration of light with wavelengths of 650 nm, 610 nm, 555 nm, 510 nm, and 470 nm after passing through the imaging optical lens 20 according to the second embodiment. Figure 8 is a schematic diagram of the field curvature and distortion aberration of light with a wavelength of 555 nm after passing through the imaging optical lens 20 according to the second embodiment. In Figure 8, the field curvature S is the field curvature in the sagittal direction, and T is the field curvature in the meridional direction.
[0087] In this embodiment, the imaging optical lens 20 has an effective aperture ENPD of 1.221 mm, a full-field image height IH of 2.697 mm, and a diagonal angle of view FOV of 197.38°. The imaging optical lens 20 satisfies the design requirements for a large aperture, a wide angle, and an ultra-thin design, has sufficient correction for chromatic aberrations on and off the optical axis, and has excellent optical characteristics.
[0088] (Third embodiment) The meanings of the symbols in the third embodiment are the same as those in the first embodiment.
[0089] FIG. 9 shows an imaging optical lens 30 according to a third embodiment of the present invention.
[0090] Tables 9 and 10 show design data for the imaging optical lens 30 according to the third embodiment of the present invention.
[0091] [Table 9]
[0092] Table 10 shows the aspheric surface data of each lens 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 curvature 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] 10 and 11 are schematic diagrams of the axial chromatic aberration and lateral chromatic aberration of light with wavelengths of 650 nm, 610 nm, 555 nm, 510 nm, and 470 nm after passing through the imaging optical lens 30 according to the third embodiment. Fig. 12 is a schematic diagram of the field curvature and distortion aberration of light with a wavelength of 555 nm after passing through the imaging optical lens 30 according to the third embodiment. In Fig. 12, the field curvature S is the field curvature in the sagittal direction, and T is the field curvature in the meridional direction.
[0098] In this embodiment, the imaging optical lens 30 has an effective aperture ENPD of 1.0138 mm, a full-field image height IH of 2.735 mm, and a diagonal angle of view FOV of 189.23°. The imaging optical lens 30 satisfies the design requirements for a large aperture, a wide angle, and an ultra-thin design, and has excellent optical properties with sufficient correction of chromatic aberrations on and off the optical axis.
[0099] (Fourth embodiment) The meanings of the symbols in the fourth embodiment are the same as those in the first embodiment.
[0100] FIG. 13 shows an imaging optical lens 40 according to a fourth embodiment of the present invention.
[0101] Tables 13 and 14 show design data for the imaging optical lens 40 according to the fourth embodiment of the present invention.
[0102] [Table 13]
[0103] Table 14 shows the aspheric surface data of each lens in the imaging optical lens 40 according to the fourth embodiment of the present invention.
[0104] [Table 14]
[0105] Tables 15 and 16 show design data for the curvature points and stationary points of each lens in the imaging optical lens 40 according to the fourth embodiment of the present invention.
[0106] [Table 15]
[0107] [Table 16]
[0108] 14 and 15 are schematic diagrams of the axial chromatic aberration and lateral chromatic aberration of light with wavelengths of 650 nm, 610 nm, 555 nm, 510 nm, and 470 nm after passing through the imaging optical lens 40 according to the fourth embodiment. Fig. 16 is a schematic diagram of the field curvature and distortion aberration of light with a wavelength of 555 nm after passing 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 meridional direction.
[0109] In this embodiment, the imaging optical lens 40 has an effective aperture ENPD of 1.027 mm, a full-field image height IH of 2.700 mm, and a diagonal angle of view FOV of 187.56°. The imaging optical lens 40 satisfies the design requirements for a large aperture, a wide angle, and an ultra-thin design, has sufficient correction for chromatic aberrations on and off the optical axis, and has excellent optical characteristics.
[0110] Table 21, which will be described later, shows values corresponding to the parameters specified by various numerical values and conditional expressions according to the first, second, third and fourth embodiments.
[0111] (Comparative embodiment) The symbols in the comparative embodiment have the same meanings as those in the first embodiment.
[0112] FIG. 17 shows an imaging optical lens 50 according to a comparative embodiment.
[0113] Tables 17 and 18 show design data for the imaging optical lens 50 according to the comparative embodiment.
[0114] [Table 17]
[0115] Table 18 shows the aspheric data of each lens in the imaging optical lens 50 according to the comparative embodiment.
[0116] [Table 18]
[0117] Tables 19 and 20 show the design data of the curvature points and stationary points of each lens in the imaging optical lens 50 according to the comparative embodiment.
[0118] [Table 19]
[0119] [Table 20]
[0120] 18 and 19 are schematic diagrams of axial chromatic aberration and lateral chromatic aberration of light with wavelengths of 650 nm, 610 nm, 555 nm, 510 nm, and 470 nm after passing through the imaging optical lens 50 according to the comparative embodiment. Fig. 24 is a schematic diagram of field curvature and distortion aberration of light with a wavelength of 555 nm after passing through the imaging optical lens 50 according to the comparative embodiment. The field curvature S in Fig. 24 is the field curvature in the sagittal direction, and T is the field curvature in the meridional direction.
[0121] Table 21 below lists values corresponding to each conditional expression of the comparative embodiment according to the above conditional expressions: Clearly, the imaging optical lens 50 according to the comparative embodiment does not satisfy the above conditional expression n1≧1.70.
[0122] In the comparative example, the imaging optical lens 50 has an effective aperture ENPD of 1.181 mm, a full field of view image height IH of 2.830 mm, and a diagonal field of view FOV of 186.61°. The imaging optical lens 50 does not meet the design requirements for a large aperture, a wide angle, and an ultra-thin design.
[0123] [Table 21]
[0124] Those skilled in the art will understand that the above embodiments are specific embodiments for realizing the present invention. In practical applications, various changes may be made to the form and details without departing from the spirit and scope of the present invention.
Claims
1. 1. An imaging optical lens, comprising: The optical lens comprises 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 positive refractive power, a sixth lens having negative refractive power, and a seventh lens having positive refractive power, which are arranged in this order from the object side to the image side, The refractive index of the first lens is n1, a distance on the optical axis between the image-forming side surface of the third lens and the object-side surface of the fourth lens is d6; the total optical length of the imaging optical lens is TTL, The field of view of the imaging optical lens is FOV, the focal length of the imaging optical lens is f; the image height of the full field of view of the imaging optical lens is IH, the seventh lens has a central radius of curvature of its object-side surface R13; The seventh lens has a central radius of curvature of its image-forming side surface of R14, n1≧1.70 0.06≦d6 / TTL≦0.08 100.00≦(FOV×f) / IH≦130.00 -1.00≦(R13+R14) / (R13-R14)≦-0.70 Satisfying the above relation, An imaging optical lens characterized by:
2. the Abbe number of the fifth lens is v5, the Abbe number of the sixth lens is v6; v5-v6≧35.00 Satisfying the above relation, 2. The imaging optical lens according to claim 1.
3. The thickness of the third lens on the optical axis is d5, The thickness of the fourth lens on the optical axis is d7, 0.35≦d5 / d7≦0.70 Satisfying the above relation, 2. The imaging optical lens according to claim 1.
4. 6.50≦TTL / f≦8.50 Satisfying the above relation, 2. The imaging optical lens according to claim 1.
5. a portion of the object side surface of the first lens that is close to the optical axis is a convex surface, a portion of the imaging side surface of the first lens that is close to the optical axis is concave; The focal length of the first lens is f1, the central curvature of the object side surface of the first lens is R1; the central curvature of the image-forming side surface of the first lens is R2; The thickness of the first lens on the optical axis is d1, −7.88≦f1 / f≦−1.93 0.96≦(R1+R2) / (R1-R2)≦3.01 0.02≦d1 / TTL≦0.14 Satisfying the above relation, 2. The imaging optical lens according to claim 1.
6. a portion of the object side surface of the second lens that is close to the optical axis is a convex surface, a portion of the imaging side surface of the second lens that is close to the optical axis is concave; The focal length of the second lens is f2, the central curvature of the object side surface of the second lens is R3; the central curvature of the image-forming side surface of the second lens is R4; The thickness of the second lens on the optical axis is d3, −8.54≦f2 / f≦−2.48 2.23≦(R3+R4) / (R3-R4)≦7.55 0.02≦d3 / TTL≦0.06 Satisfying the above relation, 2. The imaging optical lens according to claim 1.
7. a portion of the object side surface of the third lens that is close to the optical axis is a convex surface, a portion of the imaging side surface of the third lens that is close to the optical axis is concave; The focal length of the third lens is f3, the central curvature of the object side surface of the third lens is R5; The central curvature of the image-forming side surface of the third lens is R6, The thickness of the third lens on the optical axis is d5, 3.23≦f3 / f≦13.49 -7.02≦(R5+R6) / (R5-R6)≦-2.07 0.03≦d5 / TTL≦0.12 Satisfying the above relation, 2. The imaging optical lens according to claim 1.
8. a portion of the object side surface of the fourth lens that is close to the optical axis is concave, a portion of the image-forming side surface of the fourth lens that is close to the optical axis is a convex surface, The focal length of the fourth lens is f4, the central curvature of the object side surface of the fourth lens is R7, the central curvature of the image-forming side surface of the fourth lens is R8; The thickness of the fourth lens on the optical axis is d7, 1.03≦f4 / f≦3.77 0.62≦(R7+R8) / (R7-R8)≦1.88 0.06≦d7 / TTL≦0.22 Satisfying the above relation, 2. The imaging optical lens according to claim 1.
9. a portion of the object side surface of the fifth lens that is close to the optical axis is a convex surface, a portion of the imaging side surface of the fifth lens that is close to the optical axis is a convex surface, The focal length of the fifth lens is f5, the central curvature of the object side surface of the fifth lens is R9, the central curvature of the image-forming side surface of the fifth lens is R10; The fifth lens has an axial thickness of d9, 1.22≦f5 / f≦4.21 -0.15≦(R9+R10) / (R9-R10)≦0.08 0.08≦d9 / TTL≦0.25 Satisfying the above relation, 2. The imaging optical lens according to claim 1.
10. The first lens is made of a glass material, and the fourth lens is made of a glass material.
2. The imaging optical lens according to claim 1.
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