Image capturing optical lens

Abstract

To provide an image capturing optical lens which offers superior optical performance and meets the design requirements of a large aperture, wider angle of view, and extra thinness.SOLUTION: The image capturing optical lens comprises a positive first lens, a negative second lens, a positive third lens, a negative fourth lens, a positive fifth lens, and a negative sixth lens, which are arranged in order from an object side to an imaging side, and satisfies the following conditional expressions: 2.00≤f3 / f≤6.00, -2.00≤f5 / f6≤-0.79, -5.00≤R7 / R8≤-1.00, -0.90≤R9 / R10≤-0.20, 0.25≤d2 / d3≤1.00, wherein f represents a focal length of the image capturing optical lens, f3 represents a focal length of the third lens, f5 represents a focal length of the fifth lens, f6 represents a focal length of the sixth lens, R7 represents a central curvature radius of an object-side surface of the fourth lens, R8 represents a central curvature radius of an imaging-side surface of the fourth lens, R9 represents a central curvature radius of an object-side surface of the fifth lens, R10 represents a central curvature radius of an imaging-side surface of the fifth lens, d2 represents an axial distance from an imaging-side surface of the first lens to an object-side surface of the second lens, and d3 represents an axial thickness of the second lens.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to the field of optical lenses, and in particular, to an imaging optical lens applicable to mobile terminal devices such as smartphones and digital cameras, and devices having an imaging function such as surveillance cameras, PC cameras, in-vehicle cameras, and drones.

Background Art

[0002] In recent years, with the rise of various smart devices, the demand for small-sized imaging optical lenses has been increasing. Since the pixel size of the photosensitive element has become smaller, and today's electronic products tend to be excellent in function, thin, lightweight, and easy to carry, small-sized imaging optical lenses with good imaging quality are the mainstream in the market. In order to obtain better imaging quality, a multi-lens structure is widely adopted. Also, with the development of technology and the increase in diversified user needs, the pixel area of the photosensitive element has been shrinking, and the requirements for the imaging quality of the system have been continuously increasing. Therefore, in lens design, a six-element lens structure has gradually emerged. There is a demand for an imaging optical lens with excellent optical performance, large aperture, wide angle, and ultra-thin type.

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 can satisfy the design requirements of excellent optical performance, large aperture, wide angle, and ultra-thin type.

[0004] In order to solve the above technical problems, according to a first embodiment of the present invention, there is provided an imaging optical lens including a first lens having a positive refractive power, a second lens having a negative refractive power, a third lens having a positive refractive power, a fourth lens having a negative refractive power, a fifth lens having a positive refractive power, and a sixth lens having a negative refractive power, which are arranged in order from the object side toward the image forming side. The focal length of the imaging optical lens is f, the focal length of the third lens is f3, the focal length of the fifth lens is f5, the focal length of the sixth lens is f6, the radius of curvature of the center of the object side surface of the fourth lens is R7, the radius of curvature of the center of the image forming side surface of the fourth lens is R8, the radius of curvature of the center of the object side surface of the fifth lens is R9, the radius of curvature of the center of the image forming side surface of the fifth lens is R10, the on-axis distance from the image forming side surface of the first lens to the object side surface of the second lens is d2, and the on-axis thickness of the second lens is d3. An imaging optical lens is provided, which is characterized by satisfying the following relational expressions: 2.00 ≦ f3 / f ≦ 6.00, -2.00 ≦ f5 / f6 ≦ -0.79, -5.00 ≦ R7 / R8 ≦ -1.00, -0.90 ≦ R9 / R10 ≦ -0.20, 0.25 ≦ d2 / d3 ≦ 1.00

[0005] Preferably, the on-axis thickness of the first lens is d1, the overall optical length of the imaging optical lens is TTL, and the following relational expression is satisfied: 0.09 ≦ d1 / TTL ≦ 0.15

[0006] Preferably, the focal length of the fourth lens is f4, the on-axis thickness of the fourth lens is d7, and the following relational expression is satisfied: -80.00 ≦ f4 / d7 ≦ -25.00

[0007] Preferably, a portion of the object side surface of the first lens near the optical axis is a convex surface, and a portion of the image forming side surface of the first lens near the optical axis is a concave surface. The focal length of the first lens is f1, the radius of curvature of the center of the object side surface of the first lens is R1, and the radius of curvature of the center of the image forming side surface of the first lens is R2. The following relational expressions are satisfied: 0.48 ≦ f1 / f ≦ 1.52, -3.55 ≦ (R1 + R2) / (R1 - R2) ≦ -1.09

[0008] 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 forming 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 radius of curvature at the center of the object side surface of the second lens is R3, the radius of curvature at the center of the image forming side surface of the second lens is R4, the overall optical length of the imaging optical lens is TTL, and the following relational expressions are satisfied. -4.90 ≦ f2 / f ≦ -1.24, 1.36 ≦ (R3 + R4) / (R3 - R4) ≦ 5.66, 0.02 ≦ d3 / TTL ≦ 0.09

[0009] Preferably, a portion of the object side surface of the third lens close to the optical axis is a convex surface, the radius of curvature at the center of the object side surface of the third lens is R5, the radius of curvature at the center of the image forming side surface of the third lens is R6, the thickness on the optical axis of the third lens is d5, the overall optical length of the imaging optical lens is TTL, and the following relational expressions are satisfied. -2.65 ≦ (R5 + R6) / (R5 - R6) ≦ -0.51, 0.03 ≦ d5 / TTL ≦ 0.16

[0010] Preferably, a portion of the object side surface of the fourth lens close to the optical axis is a concave surface, a portion of the image forming side surface of the fourth lens close to the optical axis is a concave surface, the focal length of the fourth lens is f4, the thickness on the optical axis of the fourth lens is d7, the overall optical length of the imaging optical lens is TTL, and the following relational expressions are satisfied. -15.45 ≦ f4 / f ≦ -1.66, 0.00 ≦ (R7 + R8) / (R7 - R8) ≦ 1.00, 0.04 ≦ d7 / TTL ≦ 0.13

[0011] 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 forming side surface of the fifth lens close to the optical axis is a convex surface, the thickness on the optical axis of the fifth lens is d9, the overall optical length of the imaging optical lens is TTL, and the following relational expressions are satisfied. 0.44 ≦ f5 / f ≦ 1.95, -1.32 ≦ (R9 + R10) / (R9 - R10) ≦ -0.04, 0.05 ≦ d9 / TTL ≦ 0.17

[0012] Preferably, a portion of the object side surface of the sixth lens close to the optical axis is convex, a portion of the imaging side surface of the sixth lens close to the optical axis is concave, the center curvature radius of the object side surface of the sixth lens is R11, the center curvature radius of the imaging side surface of the sixth lens is R12, the on-axis thickness of the sixth lens is d11, the overall optical length of the imaging optical lens is TTL, and the following relational expressions are satisfied. -2.21 ≦ f6 / f ≦ -0.44, 0.50 ≦ (R11 + R12) / (R11 - R12) ≦ 3.53, 0.04 ≦ d11 / TTL ≦ 0.15

[0013] Preferably, the angle of view of the imaging optical lens is FOV, and the following relational expression is satisfied. FOV ≧ 76.44°

[0014] According to the present invention, the following effects can be obtained. That is, according to the imaging optical lens according to the present invention, it has excellent optical characteristics, and has characteristics of large aperture, wide angle, and ultra-thin type, and is particularly suitable for a portable imaging lens assembly and a WEB imaging lens composed of an imaging device such as a high-pixel CCD or CMOS.

Brief Description of the Drawings

[0015] In order to more clearly explain the technical solution means in the embodiment of the present invention, the drawings used in the following description of the embodiment will be briefly described below. However, the drawings in the following description only relate to a part of the embodiment of the present invention, and for those skilled in the art, based on these drawings, other drawings can be obtained without creative effort.

[0016]

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Embodiments for Carrying Out the Invention

[0017] To make the object, technical solution and advantages of the present invention clearer, each embodiment of the present invention will be described in detail below in conjunction with the drawings. However, those skilled in the art can understand that in each embodiment of the present invention, many technical details are presented to enable readers 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 for the protection of the present invention can be realized.

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

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

[0020] In this embodiment, when the focal length of the imaging optical lens 10 is defined as f and the focal length of the third lens L3 is defined as f3, the ratio of the focal length f3 of the third lens L3 to the system focal length (i.e., the focal length f) is specified so as to satisfy the relational expression of 2.00 ≤ f3 / f ≤ 6.00. Within the range of the conditional expression, by effectively balancing the field curvature of the system (i.e., the imaging optical lens 10), the amount of field curvature offset in the central field of view can be made smaller than 0.03 mm.

[0021] In this embodiment, when the focal length of the fifth lens L5 is defined as f5 and the focal length of the sixth lens L6 is defined as f6, the ratio of the focal length f5 of the fifth lens to the focal length f6 of the sixth lens is specified so as to satisfy the relational expression of -2.00 ≤ f5 / f6 ≤ -0.79. Within the range of the conditional expression, by reasonably distributing the optical focal length of the system, the system can have excellent imaging quality and low sensitivity.

[0022] In this embodiment, when the central radius of curvature of the object side surface of the fourth lens L4 is defined as R7 and the central radius of curvature of the imaging side surface of the fourth lens L4 is defined as R8, the shape of the fourth lens L4 is specified so as to satisfy the relational expression of -5.00 ≤ R7 / R8 ≤ -1.00. Within the range of the conditional expression, by improving the correction of the spherical aberration and distortion aberration of the imaging optical lens 10, the relational expression of "Distortion| ≤ 5%" can be satisfied, and the possibility of vignetting can be reduced.

[0023] In this embodiment, when the central radius of curvature of the object side surface of the fifth lens L5 is defined as R9 and the central radius of curvature of the imaging side surface of the fifth lens L5 is defined as R10, the shape of the fifth lens L5 is specified so as to satisfy the relational expression of -0.90 ≤ R9 / R10 ≤ -0.20. Within the range of the conditional expression, by relaxing the degree of deviation of the light passing through the fifth lens L5 and effectively correcting the chromatic aberration, the relational expression of LC| ≤ 6.0 μm for the chromatic aberration can be satisfied.

[0024] In this embodiment, when defining the on-axis distance from the image-forming side surface of the first lens L1 to the object side surface of the second lens L2 as d2 and the on-axis thickness of the second lens L2 as d3, the ratio of the air gap (i.e., the on-axis distance d2) between the first lens L1 and the second lens L2 to the center thickness (i.e., the on-axis thickness d3) of the second lens L2 is specified so as to satisfy the relational expression of 0.25 ≦ d2 / d3 ≦ 1.00. By reasonably distributing the air gap between the first lens L1 and the second lens L2 within the range of the conditional expression, the difficulty of assembly in the actual manufacturing process can be reduced, and the yield can be improved.

[0025] In this embodiment, when defining the on-axis thickness of the first lens L1 as d1 and the overall optical length of the imaging optical lens 10 as TTL, the ratio of the center thickness (i.e., the on-axis thickness d1) of the first lens L1 to TTL as the overall optical length of the system (i.e., the overall optical length TTL of the imaging optical lens 10) is specified so as to satisfy the relational expression of 0.09 ≦ d1 / TTL ≦ 0.15. Within the range of the conditional expression, aberrations can be corrected to ensure imaging quality, and the overall length of the optical system (i.e., the system) can be effectively controlled.

[0026] In this embodiment, when defining the focal length of the fourth lens L4 as f4 and the on-axis thickness of the fourth lens L4 as d7, the ratio of the negative refractive power (i.e., the focal length f4) of the fourth lens L4 to the center thickness (i.e., the on-axis thickness d7) of the fourth lens L4 is specified so as to satisfy the relational expression of -80.00 ≦ f4 / d7 ≦ -25.00. Within the range of the conditional expression, by buffering the change in the incident angle of light from a wide angle of view, light can be propagated smoothly within the optical lens group, and the refractive power intensity of the fourth lens L4 can be maintained so that aberrations are improved.

[0027] In this embodiment, a portion of the object side surface of the first lens L1 close to the optical axis is a convex surface, a portion of the imaging side surface of the first lens L1 close to the optical axis is a concave surface, and the first lens L1 has a positive refractive power. In other embodiments, the object side surface and the imaging side surface of the first lens L1 may be set to other concavo-convex distribution situations.

[0028] When the focal length of the imaging optical lens 10 is defined as f and the focal length of the first lens L1 is defined as f1, the relational expression 0.48 ≦ f1 / f ≦ 1.52 is satisfied. By controlling the positive power of the first lens L1 within a reasonable range, the aberration of the optical system can be corrected. It is preferable to satisfy 0.76 ≦ f1 / f ≦ 1.22.

[0029] When the central radius of curvature of the object side surface of the first lens L1 is defined as R1 and the central radius of curvature of the imaging side surface of the first lens L1 is defined as R2, the relational expression -3.55 ≦ (R1 + R2) / (R1 - R2) ≦ -1.09 is satisfied. By reasonably controlling the shape of the first lens L1, the first lens L1 can effectively correct the spherical aberration of the system. It is preferable to satisfy -2.22 ≦ (R1 + R2) / (R1 - R2) ≦ -1.36.

[0030] In this embodiment, a portion of the object side surface of the second lens L2 close to the optical axis is a convex surface, a portion of the imaging side surface of the second lens L2 close to the optical axis is a concave surface, and the second lens L2 has a negative refractive power. In any other embodiments, the object side surface and the imaging side surface of the second lens L2 may be set to other concavo-convex distribution situations.

[0031] When the focal length of the imaging optical lens 10 is defined as f and the focal length of the second lens L2 is defined as f2, the relational expression -4.90 ≦ f2 / f ≦ -1.24 is satisfied. By controlling the negative refractive power of the second lens L2 within a reasonable range, the aberration of the optical system can be corrected. It is preferable to satisfy -3.06 ≦ f2 / f ≦ -1.55.

[0032] When the radius of curvature of the object-side surface center of the second lens L2 is defined as R3 and the radius of curvature of the image-side surface of the second lens L2 is defined as R4, the shape of the second lens L4 is specified so as to satisfy the relational expression of 1.36 ≤ (R3 + R4) / (R3 - R4) ≤ 5.66. Within the range of the conditional expression, with the development of ultra-thin wide-angle, problems such as off-axis image angle aberration can be corrected. It is preferable to satisfy 2.18 ≤ (R3 + R4) / (R3 - R4) ≤ 4.53.

[0033] When the on-axis thickness of the second lens L2 is defined as d3 and the overall optical length of the imaging optical lens 10 is defined as TTL, the relational expression of 0.02 ≤ d3 / TTL ≤ 0.09 is satisfied. Within the range of the conditional expression, miniaturization of the system can be realized. It is preferable to satisfy 0.02 ≤ d3 / TTL ≤ 0.07.

[0034] In the present embodiment, the portion of the object-side surface of the third lens L3 close to the optical axis is a convex surface, the portion of the image-side surface of the third lens L3 close to the optical axis is a convex surface or a concave surface, and the third lens L3 has a positive refractive power. In addition, in other optional embodiments, the object-side surface and the image-side surface of the third lens L3 may be set to other concavo-convex distribution situations.

[0035] When the radius of curvature of the object-side surface center of the third lens L3 is defined as R5 and the radius of curvature of the image-side surface center of the third lens L3 is defined as R6, the shape of the third lens L3 is specified so as to satisfy the relational expression of -2.65 ≤ (R5 + R6) / (R5 - R6) ≤ -0.51. Within the range of the conditional expression, with the development of ultra-thin wide-angle, problems such as off-axis image angle aberration can be corrected. It is preferable to satisfy -1.66 ≤ (R5 + R6) / (R5 - R6) ≤ -0.64.

[0036] When the on-axis thickness of the third lens L3 is defined as d5 and the overall optical length of the imaging optical lens 10 is defined as TTL, the relational expression of 0.03 ≤ d5 / TTL ≤ 0.16 is satisfied. Within the range of the conditional expression, miniaturization of the system can be realized. It is preferable to satisfy 0.05 ≤ d5 / TTL ≤ 0.13.

[0037] In this embodiment, a portion of the object side surface of the fourth lens L4 close to the optical axis is a concave surface, a portion of the imaging side surface of the fourth lens L4 close to the optical axis is a concave surface, and the fourth lens L4 has a negative refractive power. In any other embodiment, the object side surface and the imaging side surface of the fourth lens L4 may be set to other concave and convex distribution situations.

[0038] When the focal length of the imaging optical lens 10 is defined as f and the focal length of the fourth lens L4 is defined as f4, the relational expression of -15.45 ≤ f4 / f ≤ -1.66 is satisfied. By reasonably distributing the power of the fourth lens L4, the system can have excellent imaging quality and low sensitivity. The power is related to the focal length f4. It is preferable to satisfy -9.65 ≤ f4 / f ≤ -2.08.

[0039] When the central radius of curvature of the object side surface of the fourth lens L4 is defined as R7 and the central radius of curvature of the imaging side surface of the fourth lens L4 is defined as R8, the relational expression of 0.00 ≤ (R7 + R8) / (R7 - R8) ≤ 1.00 is satisfied, specifying the shape of the fourth lens L4. When it is within the range, with the development of ultra-thin wide-angle, it is advantageous for correcting problems such as off-axis image angle aberration. It is preferable to satisfy 0.00 ≤ (R7 + R8) / (R7 - R8) ≤ 0.80.

[0040] When the on-axis thickness of the fourth lens L4 is defined as d7 and the overall optical length of the imaging optical lens 10 is defined as TTL, the relational expression of 0.04 ≤ d7 / TTL ≤ 0.13 is satisfied. Within the range of the conditional expression, miniaturization of the system can be realized. It is preferable to satisfy 0.06 ≤ d7 / TTL ≤ 0.10.

[0041] In this embodiment, a portion of the object side surface of the fifth lens L5 close to the optical axis is a convex surface, a portion of the imaging side surface of the fifth lens L5 close to the optical axis is a convex surface, and the fifth lens L5 has a positive refractive power. In any other embodiment, the object side surface and the imaging side surface of the fifth lens L5 may be set to other concave and convex distribution situations.

[0042] When the focal length of the imaging optical lens 10 is defined as f and the focal length of the fifth lens L5 is defined as f5, the relational expression 0.44 ≤ f5 / f ≤ 1.95 is satisfied. By rationally distributing the power of the fifth lens L5, the system can have excellent imaging quality and low sensitivity. The power is related to the focal length f5. Preferably, 0.70 ≤ f5 / f ≤ 1.56 is satisfied.

[0043] When the radius of curvature of the center of the object side surface of the fifth lens L5 is defined as R9 and the radius of curvature of the center of the image side surface of the fifth lens L5 is defined as R10, the shape of the fifth lens L5 is specified so as to satisfy the relational expression -1.32 ≤ (R9 + R10) / (R9 - R10) ≤ -0.04. Within the range of the conditional expression, problems such as off-axis aberration can be corrected with the development of ultra-thin wide-angle. Preferably, -0.83 ≤ (R9 + R10) / (R9 - R10) ≤ -0.05 is satisfied.

[0044] When the thickness on the optical axis of the fifth lens L5 is defined as d9 and the overall optical length of the imaging optical lens 10 is defined as TTL, the relational expression 0.05 ≤ d9 / TTL ≤ 0.17 is satisfied. Within the range of the conditional expression, miniaturization of the system can be achieved. Preferably, 0.08 ≤ d9 / TTL ≤ 0.14 is satisfied.

[0045] In this embodiment, the portion of the object side surface of the sixth lens L6 close to the optical axis is a convex surface, the portion of the image side surface of the sixth lens L6 close to the optical axis is a concave surface, and the sixth lens L6 has a negative refractive power. In any other embodiment, the object side surface and the image side surface of the sixth lens L6 may be set to other convex-concave distribution situations.

[0046] When the focal length of the imaging optical lens 10 is defined as f and the focal length of the sixth lens L6 is defined as f6, the relational expression -2.21 ≤ f6 / f ≤ -0.44 is satisfied. By rationally distributing the power of the sixth lens L6, the system can have excellent imaging quality and low sensitivity. The power is related to the focal length f6. Preferably, -1.38 ≤ f6 / f ≤ -0.55 is satisfied.

[0047] When defining the center curvature radius of the object side surface of the sixth lens L6 as R11 and the center curvature radius of the imaging side surface of the sixth lens L6 as R12, the shape of the sixth lens L6 is specified so as to satisfy the relational expression of 0.50 ≦ (R11 + R12) / (R11 - R12) ≦ 3.53. Within the range of this conditional expression, along with the development of ultra-thin wide-angle, problems such as off-axis image angle aberration can be corrected. It is preferable to satisfy 0.80 ≦ (R11 + R12) / (R11 - R12) ≦ 2.83.

[0048] When defining the on-axis thickness of the sixth lens L6 as d11 and the overall optical length of the imaging optical lens 10 as TTL, the relational expression of 0.04 ≦ d11 / TTL ≦ 0.15 is satisfied. Within the range of this conditional expression, miniaturization of the system can be realized. It is preferable to satisfy 0.06 ≦ d11 / TTL ≦ 0.12.

[0049] In this embodiment, since the angle of view FOV of the imaging optical lens 10 is 76.44° or more, wide-angle is realized and the imaging performance of the imaging optical lens 10 is excellent.

[0050] In this embodiment, when setting the image height of the imaging optical lens 10 as IH and the overall optical length of the imaging optical lens 10 as TTL, and satisfying the relational expression of TTL / IH ≦ 1.45, miniaturization of the system can be realized.

[0051] In this embodiment, since the aperture value FNO of the imaging optical lens 10 is 1.70 or less, large aperture is realized and the imaging performance of the imaging optical lens 10 is excellent.

[0052] The imaging optical lens 10 has excellent optical characteristics and can satisfy the design requirements of large aperture, wide-angle, and ultra-thin. According to the characteristics of the imaging optical lens 10, the imaging optical lens 10 is suitable for a portable imaging lens assembly and a WEB imaging lens particularly composed of imaging devices such as high-pixel CCDs and CMOSs.

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

[0054] TTL is the overall optical length (the distance on the optical axis from the object side surface of the first lens L1 to the imaging surface Si), and the unit is mm.

[0055] The aperture value FNO refers to the ratio of the effective focal length to the effective aperture of the imaging optical lens.

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

[0057] Table 1 shows the design data of the imaging optical lens 10 according to the first embodiment of the present invention.

[0058]

Table 1

[0059] The meanings of the respective reference signs are as follows. S1: Aperture R: Radius of curvature at the center of the optical surface R1: Central radius of curvature of the object side surface of the first lens L1 R2: Central radius of curvature of the imaging side surface of the first lens L1 R3: Central radius of curvature of the object side surface of the second lens L2 R4: Central radius of curvature of the imaging side surface of the second lens L2 R5: Central radius of curvature of the object side surface of the third lens L3 R6: Central radius of curvature of the imaging side surface of the third lens L3 R7: Central radius of curvature of the object side surface of the fourth lens L4 R8: Central radius of curvature of the imaging side surface of the fourth lens L4 R9: Central radius of curvature of the object side surface of the fifth lens L5 R10: Center radius of curvature of the image-forming side surface of the fifth lens L5 R11: Center radius of curvature of the object side surface of the sixth lens L6 R12: Center radius of curvature of the image-forming side surface of the sixth lens L6 R13: Center radius of curvature of the object side surface of the optical filter GF R14: Center radius of curvature of the image-forming side surface of the optical filter GF d: On-axis thickness of the lens, on-axis distance between lenses d0: On-axis distance from the aperture S1 to the object side surface of the first lens L1 d1: On-axis thickness of the first lens L1 d2: On-axis distance from the image-forming side surface of the first lens L1 to the object side surface of the second lens L2 d3: On-axis thickness of the second lens L2 d4: On-axis distance from the image-forming side surface of the second lens L2 to the object side surface of the third lens L3 d5: On-axis thickness of the third lens L3 d6: On-axis distance from the image-forming side surface of the third lens L3 to the object side surface of the fourth lens L4 d7: On-axis thickness of the fourth lens L4 d8: On-axis distance from the image-forming side surface of the fourth lens L4 to the object side surface of the fifth lens L5 d9: On-axis thickness of the fifth lens L5 d10: On-axis distance from the image-forming side surface of the fifth lens L5 to the object side surface of the sixth lens L6 d11: On-axis thickness of the sixth lens L6 d12: On-axis distance from the image-forming side surface of the sixth lens L6 to the object side surface of the optical filter GF d13: On-axis thickness of the optical filter GF d14: On-axis distance from the image-forming side surface of the optical filter GF to the image plane Si nd: Refractive index of the d-line (the d-line is green light with a wavelength of 550 nm). nd1: Refractive index of the d-line of the first lens L1 nd2: Refractive index of the d-line of the second lens L2 nd3: Refractive index of the d-line of the third lens L3 nd4: Refractive index of the d-line of the fourth lens L4 nd5: Refractive index of the d-line of the fifth lens L5 nd6: Refractive index of the d-line of the 6th lens L6 ndg: Refractive index of the d-line of the optical filter GF vd: Abbe number v1: Abbe number of the 1st lens L1 v2: Abbe number of the 2nd lens L2 v3: Abbe number of the 3rd lens L3 v4: Abbe number of the 4th lens L4 v5: Abbe number of the 5th lens L5 v6: Abbe number of the 6th lens L6 vg: Abbe number of the optical filter GF

[0060] Table 2 shows the aspherical data of each lens in the imaging optical lens 10 according to the first embodiment of the present invention.

[0061]

Table 2

[0062] For the sake of convenience, the aspherical surface of each lens surface is an aspherical surface as shown in the following formula (1). However, the present invention is not limited to the form of the aspherical polynomial represented by the 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)

[0063] Here, k is the conical coefficient, A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28, A30 are the aspherical coefficients, c is the curvature at the center of the optical surface, r is the perpendicular distance between a point on the aspherical curve and the optical axis, and z is the aspherical depth (the perpendicular distance between a point on the aspherical surface with a distance r from the optical axis and the tangent plane that touches the vertex on the aspherical optical axis).

[0064] Tables 3 and 4 show the design data of the bending points and the stopping points of each lens in the imaging optical lens 10 according to the first embodiment of the present invention. Here, P1R1 and P1R2 represent the object side surface and the imaging side surface of the first lens L1, respectively, P2R1 and P2R2 represent the object side surface and the imaging side surface of the second lens L2, respectively, P3R1 and P3R2 represent the object side surface and the imaging side surface of the third lens L3, respectively, P4R1 and P4R2 represent the object side surface and the imaging side surface of the fourth lens L4, respectively, P5R1 and P5R2 represent the object side surface and the imaging side surface of the fifth lens L5, respectively, and P6R1 and P6R2 represent the object side surface and the imaging side surface of the sixth lens L6, respectively. The data corresponding to the "bending point position" column is the perpendicular distance from the bending point provided on the surface of each lens to the optical axis 10 of the imaging optical lens. The data corresponding to the "stopping point position" column is the perpendicular distance from the stopping point provided on the surface of each lens to the optical axis 10 of the imaging optical lens.

[0065] [Table 3]

[0066] [Table 4]

[0067] FIG. 2 and FIG. 3 are schematic diagrams of axial chromatic aberration and magnification chromatic aberration of light with wavelengths of 650 nm, 610 nm, 555 nm, 510 nm, 470 nm, and 430 nm after passing through the imaging optical lens 10 according to the first embodiment. FIG. 4 is a schematic diagram of field curvature and distortion of light with a wavelength of 555 nm after passing through the imaging optical lens 10 according to the first embodiment. The field curvature S in FIG. 4 is the field curvature in the sagittal direction, and T is the field curvature in the meridional direction.

[0068] Table 25 described later shows values corresponding to parameters in which various numerical values in each embodiment are specified by conditional expressions.

[0069] As shown in Table 25, the first embodiment satisfies each conditional expression.

[0070] In this embodiment, the effective aperture ENPD of the imaging optical lens 10 is 3.442 mm, the full field image height IH is 5.120 mm, and the angular field of view FOV in the diagonal direction is 81.30°. The imaging optical lens 10 satisfies the design requirements of large aperture, wide angle, and ultra-thin type, and its axial and off-axis chromatic aberrations are sufficiently corrected and it has excellent optical characteristics.

[0071] (Second Embodiment) The second embodiment is substantially the same as the first embodiment, and the meanings of the reference numerals are the same as those in the first embodiment. Hereinafter, only the differences will be listed.

[0072] FIG. 5 shows an imaging optical lens 20 according to the second embodiment of the present invention.

[0073] Table 5 shows the design data of the imaging optical lens 20 according to the second embodiment of the present invention.

[0074]

Table 5

[0075] Table 6 shows the aspherical data of each lens in the imaging optical lens 20 according to the second embodiment of the present invention.

[0076]

Table 6

[0077] Table 7 and Table 8 show the design data of the curvature points and the stopping points of each lens in the imaging optical lens 20 according to the second embodiment of the present invention.

[0078]

Table 7

[0079]

Table 8

[0080] FIG. 6 and FIG. 7 are schematic diagrams of the axial chromatic aberration and the magnification chromatic aberration of light with wavelengths of 650 nm, 610 nm, 555 nm, 510 nm, 470 nm, and 430 nm after passing through the imaging optical lens 20 according to the second embodiment, respectively. FIG. 8 is a schematic diagram of the field curvature and the distortion aberration of light with a wavelength of 555 nm after passing 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 meridian direction.

[0081] As shown in Table 25, the second embodiment satisfies each conditional expression.

[0082] In this embodiment, the effective aperture ENPD of the imaging optical lens 20 is 3.635 mm, the full field image height IH is 5.120 mm, and the angle of view FOV in the diagonal direction is 76.44°. The imaging optical lens 20 satisfies the design requirements of large aperture, wide angle, and ultra-thin type, and its axial and off-axis chromatic aberrations are sufficiently corrected, and it has excellent optical characteristics.

[0083] (Third Embodiment) The third embodiment is substantially the same as the first embodiment, and the meanings of the reference signs are the same as those in the first embodiment. Hereinafter, only the differences will be listed.

[0084] FIG. 9 shows an imaging optical lens 30 according to the third embodiment of the present invention.

[0085] Table 9 shows the design data of the imaging optical lens 30 according to the third embodiment of the present invention.

[0086] [Table 9]

[0087] Table 10 shows the aspherical data of each lens in the imaging optical lens 30 according to the third embodiment of the present invention.

[0088] [Table 10]

[0089] Tables 11 and 12 show the design data of the curvature points and the stopping points of each lens in the imaging optical lens 30 according to the third embodiment of the present invention.

[0090] [Table 11]

[0091] [Table 12]

[0092] FIG. 10 and FIG. 11 are schematic diagrams of the axial chromatic aberration and the magnification chromatic aberration of light with wavelengths of 650 nm, 610 nm, 555 nm, 510 nm, 470 nm, and 430 nm after passing through the imaging optical lens 30 according to the third embodiment, respectively. FIG. 12 is a schematic diagram of the field curvature and the distortion aberration of light with a wavelength of 555 nm after passing 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 meridional direction.

[0093] As shown in Table 25, the third embodiment satisfies each conditional expression.

[0094] In this embodiment, the effective aperture ENPD of the imaging optical lens 30 is 3.330 mm, the full field image height IH is 5.120 mm, and the angular field of view FOV in the diagonal direction is 80.00°. The imaging optical lens 30 meets the design requirements of large aperture, wide angle, and ultra-thin type, and its axial and off-axis chromatic aberrations are sufficiently corrected, and it has excellent optical characteristics.

[0095] (Fourth Embodiment) The fourth embodiment is substantially the same as the first embodiment, and the meanings of the reference signs are the same as those in the first embodiment. Hereinafter, only the differences will be listed.

[0096] FIG. 13 shows an imaging optical lens 40 according to the fourth embodiment of the present invention.

[0097] Table 13 shows the design data of the imaging optical lens 40 according to the fourth embodiment of the present invention.

[0098] [Table 13]

[0099] Table 14 shows the aspherical data of each lens in the imaging optical lens 40 according to the fourth embodiment of the present invention.

[0100] [Table 14]

[0101] Tables 15 and 16 show the design data of the curvature points and the stop points of each lens in the imaging optical lens 40 according to the fourth embodiment of the present invention.

[0102] [Table 15]

[0103] [Table 16]

[0104] Figures 14 and 15 are schematic diagrams of the axial chromatic aberration and magnification chromatic aberration of light with wavelengths of 650 nm, 610 nm, 555 nm, 510 nm, 470 nm, and 430 nm after passing through the imaging optical lens 40 according to the fourth embodiment. Figure 16 is a schematic diagram of the field curvature and distortion 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 Figure 16 is the field curvature in the sagittal direction, and T is the field curvature in the meridian direction.

[0105] As shown in Table 25, the fourth embodiment satisfies each conditional expression.

[0106] In this embodiment, the effective aperture ENPD of the imaging optical lens 40 is 3.247 mm, the full-field image height IH is 5.120 mm, and the angular field of view FOV in the diagonal direction is 83.54°. The imaging optical lens 40 satisfies the design requirements of large aperture, wide-angle, and ultra-thin type, and its axial and off-axis chromatic aberrations are sufficiently corrected, and it has excellent optical characteristics.

[0107] (Fifth Embodiment) The fifth embodiment is substantially the same as the first embodiment, and the meanings of the reference signs are the same as those in the first embodiment. Hereinafter, only the differences will be listed.

[0108] Figure 17 shows the imaging optical lens 50 according to the fifth embodiment of the present invention.

[0109] Table 17 shows the design data of the imaging optical lens 50 according to the fifth embodiment of the present invention.

[0110] [Table 17]

[0111] Table 18 shows the aspherical data of each lens in the imaging optical lens 50 according to the fifth embodiment of the present invention.

[0112]

Table 18

[0113] Tables 19 and 20 show the design data of the curvature points and the stop points of each lens in the imaging optical lens 50 according to the fifth embodiment of the present invention.

[0114]

Table 19

[0115]

Table 20

[0116] FIG. 18 and FIG. 19 are schematic diagrams of the axial chromatic aberration and the magnification chromatic aberration of light with wavelengths of 650 nm, 610 nm, 555 nm, 510 nm, 470 nm, and 430 nm after passing through the imaging optical lens 50 according to the fifth embodiment, respectively. FIG. 20 is a schematic diagram of the field curvature and the distortion aberration of light with a wavelength of 555 nm after passing 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 meridian direction.

[0117] As shown in Table 25, the fifth embodiment satisfies the above conditional expression.

[0118] In this embodiment, the effective aperture ENPD of the imaging optical lens 50 is 3.366 mm, the full field image height IH is 5.120 mm, and the angle of view FOV in the diagonal direction is 80.82°. The imaging optical lens 50 satisfies the design requirements of large aperture, wide angle, and ultra-thin type, and its axial and off-axis chromatic aberrations are sufficiently corrected, and it has excellent optical characteristics.

[0119] (Comparative Embodiment) The symbolic meanings in the comparative embodiment are the same as those in the first embodiment, and only the differences are listed below.

[0120] FIG. 21 shows the imaging optical lens 60 according to the comparative embodiment.

[0121] Table 21 shows the design data of the imaging optical lens 60 according to the comparative embodiment.

[0122]

Table 21

[0123] Table 22 shows the aspherical data of each lens in the imaging optical lens 60 according to the comparative embodiment.

[0124]

Table 22

[0125] Tables 23 and 24 show the design data of the curvature points and the stopping points of each lens in the imaging optical lens 60 according to the comparative embodiment.

[0126]

Table 23

[0127]

Table 24

[0128] FIG. 22 and FIG. 23 are schematic diagrams of the axial chromatic aberration and the magnification chromatic aberration of light with wavelengths of 650 nm, 610 nm, 555 nm, 510 nm, 470 nm, and 430 nm after passing through the imaging optical lens 60 according to the comparative embodiment. FIG. 24 is a schematic diagram of the field curvature and the distortion of light with a wavelength of 555 nm after passing through the imaging optical lens 60 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.

[0129] Table 25 below lists the values corresponding to each conditional expression of the comparative embodiments according to the above conditions. Apparently, the imaging optical lens 60 according to the comparative embodiment does not satisfy the conditional expression -2.00 ≦ f5 / f6 ≦ -0.79.

[0130] In the comparative embodiment, the effective aperture ENPD of the imaging optical lens 60 is 3.162 mm, the full field image height IH is 5.120 mm, and the field angle FOV in the diagonal direction is 80.34°. The imaging optical lens 60 does not meet the design requirements of large aperture, wide angle, and ultra-thin type.

[0131]

Table 25

[0132] Those skilled in the art can understand that the above embodiments are specific embodiments for implementing the present invention. In actual applications, various changes may be made to its form and details without departing from the spirit and scope of the present invention.

Claims

1. 1. An imaging optical lens, comprising: The optical system comprises a first lens having positive refractive power, a second lens having negative refractive power, a third lens having positive refractive power, a fourth lens having negative refractive power, a fifth lens having positive refractive power, and a sixth lens having negative refractive power, which are arranged in order from the object side to the image side, an optical axis distance from the image-forming side surface of the first lens to the object-side surface of the second lens is d2; and an optical axis thickness of the second lens is d3, wherein the imaging optical lens has a focal length of f, a focal length of the third lens is f3, a focal length of the fifth lens is f5, a focal length of the sixth lens is f6, a central radius of curvature of the object-side surface of the fourth lens is R7, a central radius of curvature of the image-forming side surface of the fourth lens is R8, a central radius of curvature of the object-side surface of the fifth lens is R9, a central radius of curvature of the image-forming side surface of the fifth lens is R10, an optical axis distance from the image-forming side surface of the first lens to the object-side surface of the second lens is d2, and an optical axis thickness of the second lens is d3, and the imaging optical lens satisfies the following relational expressions: 2.00≦f3 / f≦6.00 -2.00≦f5 / f6≦-0.79 -5.00≦R7 / R8≦-1.00 −0.90≦R9 / R10≦−0.20 0.25≦d2 / d3≦1.00

2. 2. The imaging optical lens according to claim 1, An imaging optical lens, wherein an axial thickness of the first lens is d1, and an optical total length of the imaging optical lens is TTL, and the following relational expression is satisfied: 0.09≦d1 / TTL≦0.15

3. 2. The imaging optical lens according to claim 1, The fourth lens has a focal length of f4 and an axial thickness of d7, and the imaging optical lens satisfies the following relational expression: -80.00≦f4 / d7≦-25.00

4. 2. The imaging optical lens according to claim 1, A portion of the object side surface of the first lens close to the optical axis is a convex surface, and a portion of the image forming side surface of the first lens close to the optical axis is a concave surface, 1. An imaging optical lens, comprising: a focal length of the first lens is f1; a central radius of curvature of an object-side surface of the first lens is R1; and a central radius of curvature of an image-forming side surface of the first lens is R2, which satisfy the following relational expressions: 0.48≦f1 / f≦1.52 -3.55≦(R1+R2) / (R1-R2)≦-1.09

5. 2. The imaging optical lens according to claim 1, a portion of the second lens on an object side surface close to an optical axis is a convex surface, and a portion of the second lens on an image-forming side surface close to the optical axis is a concave surface, an imaging optical lens, characterized in that a focal length of the second lens is f2, a central radius of curvature of an object side surface of the second lens is R3, a central radius of curvature of an image side surface of the second lens is R4, and a total optical length of the imaging optical lens is TTL, and the following relational expression is satisfied: −4.90≦f2 / f≦−1.24 1.36≦(R3+R4) / (R3-R4)≦5.66 0.02≦d3 / TTL≦0.09

6. 2. The imaging optical lens according to claim 1, a portion of the object side surface of the third lens that is close to the optical axis is a convex surface, an optical lens having a central radius of curvature of an object side surface of the third lens is R5, an optical lens having a central radius of curvature of an image side surface of the third lens is R6, an optical axial thickness of the third lens is d5, and an optical total length of the imaging optical lens is TTL, the following relational expressions being satisfied: -2.65≦(R5+R6) / (R5-R6)≦-0.51 0.03≦d5 / TTL≦0.16

7. 2. The imaging optical lens according to claim 1, a portion of the fourth lens on an object side surface close to an optical axis is a concave surface, and a portion of the fourth lens on an image-forming side surface close to the optical axis is a concave surface, an optical lens having a focal length of f4, an axial thickness of d7, and a total optical length of the imaging optical lens being TTL, the imaging optical lens satisfying the following relational expression: −15.45≦f4 / f≦−1.66 0.00≦(R7+R8) / (R7-R8)≦1.00 0.04≦d7 / TTL≦0.13

8. 2. The imaging optical lens according to claim 1, a portion of the fifth lens on an object side surface close to an optical axis is a convex surface, and a portion of the fifth lens on an image-forming side surface close to the optical axis is a convex surface, An imaging optical lens, wherein an axial thickness of the fifth lens is d9, and an optical total length of the imaging optical lens is TTL, and the following relational expression is satisfied: 0.44≦f5 / f≦1.95; -1.32≦(R9+R10) / (R9-R10)≦-0.04; 0.05≦d9 / TTL≦0.17

9. 2. The imaging optical lens according to claim 1, a portion of the sixth lens on an object side surface close to an optical axis is a convex surface, and a portion of the sixth lens on an image-forming side surface close to the optical axis is a concave surface, an optical lens having a central radius of curvature of an object side surface of the sixth lens is R11, an optical lens having a central radius of curvature of an image-forming side surface of the sixth lens is R12, an optical axial thickness of the sixth lens is d11, and an optical total length of the imaging optical lens is TTL, the imaging optical lens being characterized in that −2.21≦f6 / f≦−0.44 0.50≦(R11+R12) / (R11-R12)≦3.53 0.04≦d11 / TTL≦0.15

10. 2. The imaging optical lens according to claim 1, The imaging optical lens has an angle of view, which is an FOV, and which satisfies the following relational expression: FOV≧76.44°

Images