CN111077645B

CN111077645B - Image pickup optical lens

Info

Publication number: CN111077645B
Application number: CN201911335896.8A
Authority: CN
Inventors: 王康
Original assignee: Chengrui Optics Changzhou Co Ltd
Current assignee: Chengrui Optics Changzhou Co Ltd
Priority date: 2019-12-23
Filing date: 2019-12-23
Publication date: 2021-12-14
Anticipated expiration: 2039-12-23
Also published as: CN111077645A

Abstract

The invention relates to the field of optical lenses, and discloses an image pickup optical lens, which sequentially comprises the following components from an object side to an image side: the lens comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens, and the following relational expressions are satisfied: f2/f is more than or equal to 2.50 and less than or equal to 6.00; f1/f is not less than-1.20 and is not less than-2.50; f6/f is not less than 3.50 and not more than-1.90; R9/R10 is not less than-2.00 and is not less than-6.40; d9/d8 is more than or equal to 1.50 and less than or equal to 2.50. The camera optical lens provided by the invention has good optical performance, and meets the design requirements of large aperture, wide angle and ultra-thinness.

Description

Image pickup optical lens

Technical Field

The present invention relates to the field of optical lenses, and more particularly, to an imaging optical lens suitable for portable terminal devices such as smart phones and digital cameras, and imaging apparatuses such as monitors and PC lenses.

Background

In recent years, with the rise of smart phones, the demand of miniaturized camera lenses is increasing, and the photosensitive devices of general camera lenses are not limited to two types, namely, a Charge Coupled Device (CCD) or a Complementary Metal-Oxide Semiconductor (CMOS) Device, and due to the refinement of Semiconductor manufacturing technology, the pixel size of the photosensitive devices is reduced, and in addition, the current electronic products are developed in a form of being excellent in function, light, thin, short and small, so that the miniaturized camera lenses with good imaging quality are the mainstream in the current market.

In order to obtain better imaging quality, the lens mounted on the mobile phone camera conventionally adopts a three-piece or four-piece lens structure. Moreover, with the development of technology and the increase of diversified demands of users, under the conditions that the pixel area of the photosensitive device is continuously reduced and the requirements of the system on the imaging quality are continuously improved, five-piece and six-piece lens structures gradually appear in the design of the lens. There is a strong demand for a wide-angle imaging lens having excellent optical characteristics, being extremely thin, and sufficiently correcting chromatic aberration.

Disclosure of Invention

In view of the above problems, an object of the present invention is to provide an imaging optical lens that has good optical performance and satisfies design requirements for a large aperture, ultra-thin thickness, and wide angle.

To solve the above-mentioned problems, an embodiment of the present invention provides an imaging optical lens, in order from an object side to an image side, comprising: the lens comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens;

the focal length of the image pickup optical lens is f, the focal length of the first lens is f1, the focal length of the second lens is f2, the focal length of the sixth lens is f6, the curvature radius of the object side surface of the fifth lens is R9, the curvature radius of the image side surface of the fifth lens is R10, the on-axis distance from the image side surface of the fourth lens to the object side surface of the fifth lens is d8, the on-axis thickness of the fifth lens is d9, and the following relational expressions are satisfied: f2/f is more than or equal to 2.50 and less than or equal to 6.00; f1/f is not less than-1.20 and is not less than-2.50; f6/f is not less than 3.50 and not more than-1.90; R9/R10 is not less than-2.00 and is not less than-6.40; d9/d8 is more than or equal to 1.50 and less than or equal to 2.50.

Preferably, the radius of curvature of the object-side surface of the third lens is R5, the radius of curvature of the image-side surface of the third lens is R6, and the following relationship is satisfied: R5/R6 is not less than-1.80 and is not less than-4.00.

Preferably, the curvature radius of the object-side surface of the first lens element is R1, the curvature radius of the image-side surface of the first lens element is R2, the on-axis thickness of the first lens element is d1, and the total optical length of the imaging optical lens system is TTL and satisfies the following relationship: (R1+ R2)/(R1-R2) is not more than 0.53 and not more than 2.20; d1/TTL is more than or equal to 0.03 and less than or equal to 0.20.

Preferably, the curvature radius of the object-side surface of the second lens element is R3, the curvature radius of the image-side surface of the second lens element is R4, the on-axis thickness of the second lens element is d3, and the total optical length of the imaging optical lens system is TTL and satisfies the following relationship: -6.02 ≤ (R3+ R4)/(R3-R4) is ≤ 0.72; d3/TTL is more than or equal to 0.02 and less than or equal to 0.21.

Preferably, the focal length of the third lens element is f3, the radius of curvature of the object-side surface of the third lens element is R5, the radius of curvature of the image-side surface of the third lens element is R6, the on-axis thickness of the third lens element is d5, the total optical length of the image pickup optical lens is TTL, and the following relationships are satisfied: f3/f is more than or equal to 0.59 and less than or equal to 1.95; (R5+ R6)/(R5-R6) is not more than 0.15 and not more than 0.89; d5/TTL is more than or equal to 0.06 and less than or equal to 0.22.

Preferably, the focal length of the fourth lens element is f4, the radius of curvature of the object-side surface of the fourth lens element is R7, the radius of curvature of the image-side surface of the fourth lens element is R8, the on-axis thickness of the fourth lens element is d7, the total optical length of the image pickup optical lens is TTL, and the following relationships are satisfied: f4/f is not less than 4.34 and not more than-1.27; 2.24-1.02 of (R7+ R8)/(R7-R8); d7/TTL is more than or equal to 0.02 and less than or equal to 0.08.

Preferably, the focal length of the fifth lens element is f5, the total optical length of the image pickup optical lens is TTL, and the following relationship is satisfied: f5/f is more than or equal to 0.68 and less than or equal to 2.80; (R9+ R10)/(R9-R10) is not more than 0.17 and not more than 1.09; d9/TTL is more than or equal to 0.03 and less than or equal to 0.17.

Preferably, a curvature radius of an object-side surface of the sixth lens element is R11, a curvature radius of an image-side surface of the sixth lens element is R12, an on-axis thickness of the sixth lens element is d11, and an optical total length of the imaging optical lens system is TTL and satisfies the following relationship: 1.20-6.22 percent (R11+ R12)/(R11-R12); d11/TTL is more than or equal to 0.02 and less than or equal to 0.19.

Preferably, the combined focal length of the first lens and the second lens is f12, and the following relation is satisfied: f12/f is not less than 13.40 and not more than-2.52.

Preferably, the F number of the diaphragm of the imaging optical lens is FNO, and satisfies the following relationship: FNO is less than or equal to 2.41.

The invention has the beneficial effects that: the imaging optical lens according to the present invention has excellent optical characteristics, and has characteristics of a large aperture, a wide angle of view, and an ultra-thin profile, and is particularly suitable for a mobile phone camera lens module and a WEB camera lens which are constituted by high-pixel imaging elements such as CCDs and CMOSs.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without inventive efforts, wherein:

fig. 1 is a schematic configuration diagram of an imaging optical lens according to a first embodiment of the present invention;

FIG. 2 is a schematic axial aberration diagram of the imaging optical lens of FIG. 1;

fig. 3 is a schematic diagram of chromatic aberration of magnification of the imaging optical lens shown in fig. 1;

FIG. 4 is a schematic view of curvature of field and distortion of the imaging optical lens of FIG. 1;

fig. 5 is a schematic configuration diagram of an imaging optical lens according to a second embodiment of the present invention;

FIG. 6 is a schematic axial aberration diagram of the imaging optical lens of FIG. 5;

fig. 7 is a schematic diagram of chromatic aberration of magnification of the imaging optical lens shown in fig. 5;

FIG. 8 is a schematic view of curvature of field and distortion of the imaging optical lens of FIG. 5;

fig. 9 is a schematic configuration diagram of an imaging optical lens according to a third embodiment of the present invention;

fig. 10 is a schematic view of axial aberrations of the image pickup optical lens shown in fig. 9;

fig. 11 is a schematic diagram of chromatic aberration of magnification of the imaging optical lens shown in fig. 9;

FIG. 12 is a schematic view of curvature of field and distortion of the imaging optical lens of FIG. 9;

fig. 13 is a schematic configuration diagram of an imaging optical lens according to a fourth embodiment of the present invention;

fig. 14 is a schematic view of axial aberrations of the image pickup optical lens shown in fig. 13;

fig. 15 is a schematic diagram of chromatic aberration of magnification of the imaging optical lens shown in fig. 13;

fig. 16 is a schematic view of curvature of field and distortion of the imaging optical lens shown in fig. 13.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, it will be appreciated by those of ordinary skill in the art that numerous technical details are set forth in order to provide a better understanding of the present invention in its various embodiments. However, the technical solution claimed in the present invention can be implemented without these technical details and various changes and modifications based on the following embodiments.

(first embodiment)

Referring to the drawings, the present invention provides an image pickup optical lens 10. Fig. 1 shows an imaging optical lens 10 according to a first embodiment of the present invention, and the imaging optical lens 10 includes six lenses. Specifically, the imaging optical lens 10, in order from an object side to an image side, includes: the lens comprises a first lens L1, a second lens L2, a diaphragm S1, a third lens L3, a fourth lens L4, a fifth lens L5 and a sixth lens L6. An optical element such as an optical filter (filter) GF may be disposed between the sixth lens L6 and the image plane Si.

The first lens element L1 with negative refractive power, the second lens element L2 with positive refractive power, the third lens element L3 with positive refractive power, the fourth lens element L4 with negative refractive power, the fifth lens element L5 with positive refractive power and the sixth lens element L6 with negative refractive power.

In the present embodiment, 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, and the following relational expression is satisfied: f2/f is more than or equal to 2.50 and less than or equal to 6.00, the ratio of the focal length of the second lens to the focal length of the system is specified, and the performance of the optical system is improved in a conditional expression range. Preferably, 2.53. ltoreq. f 2/f. ltoreq.5.97 is satisfied.

Defining the focal length f of the image pickup optical lens 10 and the focal length f1 of the first lens L1, the following relations are satisfied: -2.50 ≦ f1/f ≦ -1.20, specifying the ratio of the focal length of the first lens to the focal length of the system, which contributes to the spherical aberration correction within the conditional range.

Defining the focal length f of the image pickup optical lens 10 and the focal length f6 of the sixth lens L6, the following relations are satisfied: f6/f is more than or equal to 3.50 and less than or equal to-1.90, the ratio of the focal length of the sixth lens to the focal length of the system is specified, and the field curvature correction is facilitated in a conditional expression range, so that the imaging quality is improved. The curvature radius of the object side surface of the fifth lens L5 is defined as R9, the curvature radius of the image side surface of the fifth lens L5 is defined as R10, and the following relational expressions are satisfied: R9/R10 is more than or equal to-2.00 at 6.40, and the shape of the fifth lens is defined, so that the deflection degree of light rays passing through the lens can be alleviated within the range defined by the conditional expression, and the aberration can be effectively reduced.

Defining an on-axis distance d8 from an image-side surface of the fourth lens L4 to an object-side surface of the fifth lens L5, an on-axis thickness d9 of the fifth lens L5, the following relationship is satisfied: d9/d8 is more than or equal to 1.50 and less than or equal to 2.50, and when d9/d8 meets the condition, the total length of the system can be effectively compressed, and ultra-thinning is realized.

The curvature radius of the object side surface of the third lens L3 is defined as R5, the curvature radius of the image side surface of the third lens L3 is defined as R6, and the following relational expressions are satisfied: R5/R6 is more than or equal to-1.80 at the ratio of-4.00 to-1.80, and the shape of the third lens is defined, so that the deflection degree of light rays passing through the lens can be alleviated within the range defined by the conditional expression, and the aberration can be effectively reduced.

The curvature radius of the object side surface of the first lens L1 is defined as R1, the curvature radius of the image side surface of the first lens L1 is defined as R2, and the following relational expressions are satisfied: 0.53 ≦ (R1+ R2)/(R1-R2) ≦ 2.20, and the shape of the first lens L1 is appropriately controlled so that the first lens L1 can effectively correct the system spherical aberration, preferably, 0.85 ≦ (R1+ R2)/(R1-R2) ≦ 1.76.

The total optical length of the imaging optical lens 10 is TTL, and the on-axis thickness of the first lens L1 is d1, which satisfies the following relation: d1/TTL is more than or equal to 0.03 and less than or equal to 0.20, and ultra-thinning is favorably realized within the range of conditional expressions. Preferably, 0.04. ltoreq. d 1/TTL. ltoreq.0.16 is satisfied.

The curvature radius of the object side surface of the second lens L2 is defined as R3, the curvature radius of the image side surface of the second lens L2 is defined as R4, and the following relational expressions are satisfied: -6.02 ≦ (R3+ R4)/(R3-R4) ≦ -0.72, and defines the shape of the second lens L2 in a range in which the lens is favorably corrected for chromatic aberration on the axis as it progresses to an ultra-thin wide angle, preferably satisfying-3.76 ≦ (R3+ R4)/(R3-R4) ≦ -0.90.

The on-axis thickness of the second lens L2 is d3, the total optical length of the imaging optical lens system 10 is TTL, and the following relationship is satisfied: d3/TTL is more than or equal to 0.02 and less than or equal to 0.21, and ultra-thinning is favorably realized within the range of conditional expressions. Preferably, 0.04. ltoreq. d 3/TTL. ltoreq.0.16 is satisfied.

Defining the focal length of the image pickup optical lens 10 as f, and the focal length of the third lens L3 as f3, the following relations are satisfied: f3/f is more than or equal to 0.59 and less than or equal to 1.95, and the system has better imaging quality and lower sensitivity through reasonable distribution of the focal power. Preferably, 0.95. ltoreq. f 3/f. ltoreq.1.56 is satisfied.

The curvature radius of the object side surface of the third lens L3 is R5, the curvature radius of the image side surface of the third lens L3 is R6, and the following relational expression is satisfied: the shape of the third lens is not less than 0.15 and not more than (R5+ R6)/(R5-R6) and not more than 0.89, and the deflection degree of the light passing through the lens can be alleviated within the range specified by the conditional expression, so that the aberration can be effectively reduced. Preferably, 0.25. ltoreq. (R5+ R6)/(R5-R6). ltoreq.0.72 is satisfied.

The on-axis thickness of the third lens L3 is d5, the total optical length of the imaging optical lens system 10 is TTL, and the following relationship is satisfied: d5/TTL is more than or equal to 0.06 and less than or equal to 0.22, and ultra-thinning is facilitated in the conditional expression range. Preferably, 0.10. ltoreq. d 5/TTL. ltoreq.0.18 is satisfied.

Defining the focal length of the image pickup optical lens 10 as f, and the focal length of the fourth lens as f4, the following relations are satisfied: 4.34. ltoreq. f 4/f. ltoreq. 1.27, specifies a ratio of the focal length of the fourth lens to the focal length of the system, contributes to improvement of the optical system performance within a conditional range, and preferably satisfies-2.71. ltoreq. f 4/f. ltoreq. 1.59.

The curvature radius of the object side surface of the fourth lens L4 is R7, and the curvature radius of the image side surface of the fourth lens L4 is R8, and the following relations are satisfied: 2.24-1.02 of (R7+ R8)/(R7-R8). The shape of the fourth lens L4 is defined, and when the fourth lens is within the range, it is advantageous to correct the problems such as aberration of the off-axis view angle as the thickness and the angle of view are increased. Preferably, it satisfies-1.40. ltoreq. (R7+ R8)/(R7-R8). ltoreq.0.82.

The on-axis thickness of the fourth lens L4 is d7, the total optical length of the imaging optical lens system 10 is TTL, and the following relationship is satisfied: d7/TTL is more than or equal to 0.02 and less than or equal to 0.08, and ultra-thinning is favorably realized within the range of conditional expressions. Preferably, 0.03. ltoreq. d 7/TTL. ltoreq.0.06 is satisfied.

Defining the focal length of the fifth lens L5 as f5, the following relation is satisfied: f5/f is more than or equal to 0.68 and less than or equal to 2.80. The definition of the fifth lens L5 can effectively make the light ray angle of the camera lens smooth, and reduce tolerance sensitivity. Preferably, 1.10. ltoreq. f 5/f. ltoreq.2.24 is satisfied.

The curvature radius of the object side surface of the fifth lens L5 is R9, the curvature radius of the image side surface of the fifth lens L5 is R10, and the following relational expression is satisfied: the shape of the fifth lens L5 is defined to be not less than 0.17 (R9+ R10)/(R9-R10) and not more than 1.09, and when the shape is within the range, the aberration of the off-axis picture angle is favorably corrected with the development of an ultra-thin wide angle. Preferably, 0.27. ltoreq. R9+ R10)/(R9-R10. ltoreq.0.88 is satisfied.

The on-axis thickness of the fifth lens L5 is d9, the total optical length of the imaging optical lens system 10 is TTL, and the following relationship is satisfied: d9/TTL is more than or equal to 0.03 and less than or equal to 0.17, and ultra-thinning is favorably realized within the range of conditional expressions. Preferably, 0.05. ltoreq. d 9/TTL. ltoreq.0.13 is satisfied.

The curvature radius of the object side surface of the sixth lens L6 is defined as R11, the curvature radius of the image side surface of the sixth lens L6 is defined as R12, and the following relational expressions are satisfied: 1.20 (R11+ R12)/(R11-R12) is not more than 6.22, and the shape of the sixth lens L6 is defined, and when the shape is within the condition range, the problem of aberration of off-axis picture angle is favorably corrected along with the development of ultra-thin wide-angle. Preferably, 1.92. ltoreq. (R11+ R12)/(R11-R12). ltoreq.4.98 is satisfied.

The on-axis thickness of the sixth lens element L6 is d11, the total optical length of the imaging optical lens system 10 is TTL, and the following relationships are satisfied: d11/TTL is more than or equal to 0.02 and less than or equal to 0.19, and ultra-thinning is facilitated in the conditional expression range. Preferably, 0.04. ltoreq. d 11/TTL. ltoreq.0.15 is satisfied.

In the present embodiment, the image height of the entire imaging optical lens 10 is IH, and the following conditional expression is satisfied: TTL/IH is less than or equal to 2.45, thereby realizing ultra-thinning.

In the present embodiment, the number of apertures FNO of the imaging optical lens 10 is 2.41 or less. The large aperture is large, and the imaging performance is good.

In the present embodiment, the field angle FOV of the imaging optical lens 10 is equal to or larger than 132 °, thereby achieving a wide angle.

In the present embodiment, the focal length of the imaging optical lens 10 is f, and the combined focal length of the first lens L1 and the second lens L2 is f12, which satisfies the following conditional expressions: f12/f is not less than 13.40 and not more than-2.52, in the condition range, the aberration and distortion of the image pickup optical lens 10 can be eliminated, and the back focal length of the image pickup optical lens 10 can be suppressed, thereby maintaining the miniaturization of the image lens system. Preferably, it satisfies-8.37. ltoreq. f 12/f. ltoreq-3.15.

When the above relationship is satisfied, the imaging optical lens 10 has good optical performance, and can satisfy design requirements of large aperture, wide angle and ultra-thinness; in accordance with the characteristics of the optical lens 10, the optical lens 10 is particularly suitable for a mobile phone camera lens module and a WEB camera lens which are configured by image pickup devices such as a high-pixel CCD and a CMOS.

The image pickup optical lens 10 of the present invention will be explained below by way of example. The symbols described in the respective examples are as follows. The unit of focal length, on-axis distance, curvature radius, on-axis thickness, position of reverse curvature and position of stagnation point is mm.

TTL: the total optical length (on-axis distance from the object side surface of the first lens L1 to the image plane) in units of mm;

preferably, the object side surface and/or the image side surface of the lens may be further provided with an inflection point and/or a stagnation point to meet the requirement of high-quality imaging.

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

[ TABLE 1 ]

Wherein each symbol has the following meaning.

S1: an aperture;

r: the radius of curvature of the optical surface and the radius of curvature of the lens as the center;

r1: the radius of curvature of the object-side surface of the first lens L1;

r2: the radius of curvature of the image-side surface of the first lens L1;

r3: the radius of curvature of the object-side surface of the second lens L2;

r4: the radius of curvature of the image-side surface of the second lens L2;

r5: the radius of curvature of the object-side surface of the third lens L3;

r6: the radius of curvature of the image-side surface of the third lens L3;

r7: the radius of curvature of the object-side surface of the fourth lens L4;

r8: the radius of curvature of the image-side surface of the fourth lens L4;

r9: a radius of curvature of the object side surface of the fifth lens L5;

r10: a radius of curvature of the image-side surface of the fifth lens L5;

r11: a radius of curvature of the object side surface of the sixth lens L6;

r12: a radius of curvature of the image-side surface of the sixth lens L6;

r13: radius of curvature of the object side of the optical filter GF;

r14: the radius of curvature of the image-side surface of the optical filter GF;

d: an on-axis thickness of the lenses and an on-axis distance between the lenses;

d 0: the on-axis distance of the stop S1 to the object-side surface of the first lens L1;

d 1: the on-axis thickness of the first lens L1;

d 2: the on-axis distance from the image-side surface of the first lens L1 to the object-side surface of the second lens L2;

d 3: the on-axis thickness of the second lens L2;

d 4: the on-axis distance from the image-side surface of the second lens L2 to the object-side surface of the third lens L3;

d 5: the on-axis thickness of the third lens L3;

d 6: the on-axis distance from the image-side surface of the third lens L3 to the object-side surface of the fourth lens L4;

d 7: the on-axis thickness of the fourth lens L4;

d 8: an on-axis distance from an image-side surface of the fourth lens L4 to an object-side surface of the fifth lens L5;

d 9: the on-axis thickness of the fifth lens L5;

d 10: an on-axis distance from an image-side surface of the fifth lens L5 to an object-side surface of the sixth lens L6;

d 11: the on-axis thickness of the sixth lens L6;

d 12: the on-axis distance from the image-side surface of the sixth lens L6 to the object-side surface of the optical filter GF;

d 13: on-axis thickness of the optical filter GF;

d 14: the on-axis distance from the image side surface of the optical filter GF to the image surface;

nd: the refractive index of the d-line;

nd 1: the refractive index of the d-line of the first lens L1;

nd 2: the refractive index of the d-line of the second lens L2;

nd 3: the refractive index of the d-line of the third lens L3;

nd 4: the refractive index of the d-line of the fourth lens L4;

nd 5: the refractive index of the d-line of the fifth lens L5;

nd 6: the refractive index of the d-line of the sixth lens L6;

ndg: the refractive index of the d-line of the optical filter GF;

vd: an Abbe number;

v 1: abbe number of the first lens L1;

v 2: abbe number of the second lens L2;

v 3: abbe number of the third lens L3;

v 4: abbe number of the fourth lens L4;

v 5: abbe number of the fifth lens L5;

v 6: abbe number of the sixth lens L6;

vg: abbe number of the optical filter GF.

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

[ TABLE 2 ]

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

IH: image height

y＝(x²/R)/[1+{1-(k+1)(x²/R²)}^1/2]+A4x⁴+A6x⁶+A8x⁸+A10x¹⁰+A12x¹²+A14x¹⁴+A16x¹⁶+A18x¹⁸+A20x²⁰ (1)

For convenience, the aspherical surface of each lens surface uses the aspherical surface shown in the above formula (1). However, the present invention is not limited to the aspherical polynomial form expressed by this formula (1).

Tables 3 and 4 show the inflection point and stagnation point design data of each lens in the imaging optical lens 10 according to the first embodiment of the present invention. P1R1 and P1R2 represent the object-side surface and the image-side surface of the first lens L1, P2R1 and P2R2 represent the object-side surface and the image-side surface of the second lens L2, P3R1 and P3R2 represent the object-side surface and the image-side surface of the third lens L3, P4R1 and P4R2 represent the object-side surface and the image-side surface of the fourth lens L4, P5R1 and P5R2 represent the object-side surface and the image-side surface of the fifth lens L5, and P6R1 and P6R2 represent the object-side surface and the image-side surface of the sixth lens L6, respectively. The "inflection point position" field correspondence data is a vertical distance from an inflection point set on each lens surface to the optical axis of the image pickup optical lens 10. The "stagnation point position" field corresponding data is the vertical distance from the stagnation point set on each lens surface to the optical axis of the imaging optical lens 10.

[ TABLE 3 ]

[ TABLE 4 ]

	Number of stagnation points	Location of stagnation 1	Location of stagnation 2
				P1R1	0
P1R2	0
				P2R1	1	1.285
P2R2	0
				P3R1	0
P3R2	0
				P4R1	0
P4R2	1	0.805
				P5R1	2	1.575	2.105
P5R2	0
				P6R1	1	1.205
P6R2	1	1.635

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

Table 17 shown later shows values corresponding to the parameters specified in the conditional expressions for the respective numerical values in examples 1, 2, 3, and 4.

As shown in table 14, the first embodiment satisfies each conditional expression.

In the present embodiment, the imaging optical lens has an entrance pupil diameter of 0.708mm, a full field image height of 3.500mm, a diagonal field angle of 136.00 °, a wide angle, and a high profile, and has excellent optical characteristics with on-axis and off-axis chromatic aberration sufficiently corrected.

(second embodiment)

The second embodiment is basically the same as the first embodiment, the same reference numerals as in the first embodiment, and only different points will be described below.

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

[ TABLE 5 ]

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

[ TABLE 6 ]

Tables 7 and 8 show the inflection point and stagnation point design data of each lens in the imaging optical lens 20 according to the second embodiment of the present invention.

[ TABLE 7 ]

	Number of points of inflection	Position of reverse curvature 1	Position of reverse curvature 2	Position of reverse curvature 3	Position of reverse curve 4
						P1R1	0
P1R2	2	1.835	2.405
						P2R1	2	0.945	1.325
P2R2	2	0.935	1.075
						P3R1	1	0.405
P3R2	0
						P4R1	0
P4R2	1	0.325
						P5R1	2	1.055	1.815
P5R2	3	0.545	1.365	2.085
						P6R1	4	0.465	1.775	2.055	2.225
P6R2	1	0.535

[ TABLE 8 ]

	Number of stagnation points	Location of stagnation 1	Location of stagnation 2
				P1R1	0
P1R2	0
				P2R1	0
P2R2	0
				P3R1	0
P3R2	0
				P4R1	0
P4R2	1	0.715
				P5R1	2	1.545	1.975
P5R2	1	2.155
				P6R1	1	0.995
P6R2	1	1.535

Fig. 6 and 7 are schematic diagrams showing axial aberrations and chromatic aberration of magnification of light having wavelengths of 650nm, 610nm, 555nm, 510nm, and 470nm passing through the imaging optical lens 20 according to the second embodiment. Fig. 8 is a schematic view showing curvature of field and distortion of light having a wavelength of 555nm after passing through the imaging optical lens 20 according to the second embodiment.

As shown in table 17, the second embodiment satisfies each conditional expression.

In the present embodiment, the imaging optical lens has an entrance pupil diameter of 0.609mm, a full field image height of 3.500mm, a diagonal field angle of 137.00 °, a wide angle, and a high profile, and has excellent optical characteristics with on-axis and off-axis chromatic aberration sufficiently corrected.

(third embodiment)

The third embodiment is basically the same as the first embodiment, the same reference numerals as in the first embodiment, and only different points will be described below.

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

[ TABLE 9 ]

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

[ TABLE 10 ]

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

[ TABLE 11 ]

	Number of points of inflection	Position of reverse curvature 1	Position of reverse curvature 2	Position of reverse curvature 3
					P1R1	0
P1R2	0
					P2R1	1	1.245
P2R2	0
					P3R1	0
P3R2	0
					P4R1	0
P4R2	1	0.975
					P5R1	1	0.635
P5R2	2	0.875	1.415
					P6R1	3	0.525	1.455	2.355
P6R2	1	0.705

[ TABLE 12 ]

	Number of stagnation points	Location of stagnation 1	Location of stagnation 2
				P1R1	0
P1R2	0
				P2R1	0
P2R2	0
				P3R1	0
P3R2	0
				P4R1	0
P4R2	0
				P5R1	1	1.325
P5R2	0
				P6R1	2	1.045	1.875
P6R2	1	2.205

Fig. 10 and 11 are schematic diagrams showing axial aberrations and chromatic aberration of magnification of light having wavelengths of 650nm, 610nm, 555nm, 510nm, and 470nm passing through the imaging optical lens 30 according to the third embodiment. Fig. 12 is a schematic view showing curvature of field and distortion of light having a wavelength of 555nm after passing through the imaging optical lens 30 according to the third embodiment.

Table 17 below shows the numerical values corresponding to the respective conditional expressions in the present embodiment in accordance with the conditional expressions. Obviously, the imaging optical system of the present embodiment satisfies the above conditional expressions.

In the present embodiment, the imaging optical lens has an entrance pupil diameter of 0.749mm, a full field image height of 3.280mm, a diagonal field angle of 132.00 °, a wide angle of view, and a high profile, and has excellent optical characteristics with on-axis and off-axis chromatic aberration sufficiently corrected.

(fourth embodiment)

The fourth embodiment is basically the same as the first embodiment, and the same reference numerals as in the first embodiment, and only different points will be described below.

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

[ TABLE 13 ]

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

[ TABLE 14 ]

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

[ TABLE 15 ]

	Number of points of inflection	Position of reverse curvature 1	Position of reverse curvature 2	Reverse bendingPoint location 3	Position of reverse curve 4
						P1R1	2	1.855	2.035
P1R2	1	1.635
						P2R1	1	1.135
P2R2	1	0.795
						P3R1	0
P3R2	0
						P4R1	0
P4R2	2	0.115	0.835
						P5R1	2	1.025	1.605
P5R2	2	0.735	1.445
						P6R1	3	0.445	1.365	1.865
P6R2	4	0.585	2.325	2.425	2.695

[ TABLE 16 ]

Fig. 14 and 15 are schematic diagrams showing axial aberrations and chromatic aberrations of magnification of light having wavelengths of 650nm, 610nm, 555nm, 510nm, and 470nm passing through the imaging optical lens 40 according to the fourth embodiment. Fig. 16 is a schematic view showing curvature of field and distortion of light having a wavelength of 555nm after passing through the imaging optical lens 40 according to the fourth embodiment.

In the present embodiment, the imaging optical lens has an entrance pupil diameter of 0.68mm, a full field image height of 3.280mm, a diagonal field angle of 136.00 °, a wide angle, and a high profile, and has excellent optical characteristics with on-axis and off-axis chromatic aberration sufficiently corrected.

[ TABLE 17 ]

Parameter and condition formula	Example 1	Example 2	Example 3	Example 4
					f2/f	4.21	5.93	2.55	3.20
f1/f	-1.85	-2.50	-1.25	-1.73
					f6/f	-2.92	-1.95	-3.49	-2.38
R9/R10	-6.39	-5.70	-2.04	-3.60
					d9/d8	1.73	2.48	1.57	2.14
f	1.700	1.463	1.799	1.632
					f1	-3.151	-3.654	-2.240	-2.820
f2	7.150	8.679	4.586	5.227
					f3	2.011	1.901	2.154	2.071
f4	-3.690	-2.988	-3.435	-3.385
					f5	3.177	2.004	3.053	2.465
f6	-4.961	-2.852	-6.286	-3.888
					f12	-9.029	-9.802	-6.792	-10.782
Fno	2.40	2.40	2.40	2.40

Where Fno is the F-number of the diaphragm of the imaging optical lens.

It will be understood by those of ordinary skill in the art that the foregoing embodiments are specific embodiments for practicing the invention, and that various changes in form and details may be made therein without departing from the spirit and scope of the invention in practice.

Claims

1. An imaging optical lens, comprising six lens elements in order from an object side to an image side: a first lens element with negative refractive power, a second lens element with positive refractive power, a third lens element with positive refractive power, a fourth lens element with negative refractive power, a fifth lens element with positive refractive power, and a sixth lens element with negative refractive power;

the focal length of the imaging optical lens is f, the focal length of the first lens element is f1, the focal length of the second lens element is f2, the focal length of the sixth lens element is f6, the curvature radius of the object-side surface of the third lens element is R5, the curvature radius of the image-side surface of the third lens element is R6, the curvature radius of the object-side surface of the fifth lens element is R9, the curvature radius of the image-side surface of the fifth lens element is R10, the on-axis distance from the image-side surface of the fourth lens element to the object-side surface of the fifth lens element is d8, the on-axis thickness of the fifth lens element is d9, and the following relations are satisfied:

2.50≤f2/f≤6.00；

-2.50≤f1/f≤-1.20；

-3.50≤f6/f≤-1.90；

-6.40≤R9/R10≤-2.00；

1.50≤d9/d8≤2.50；

-4.00≤R5/R6≤-1.80。

2. the image-capturing optical lens unit according to claim 1, wherein the radius of curvature of the object-side surface of the first lens element is R1, the radius of curvature of the image-side surface of the first lens element is R2, the on-axis thickness of the first lens element is d1, the total optical length of the image-capturing optical lens unit is TTL, and the following relationships are satisfied:

0.53≤(R1+R2)/(R1-R2)≤2.20；

0.03≤d1/TTL≤0.20。

3. the image-capturing optical lens unit according to claim 1, wherein the radius of curvature of the object-side surface of the second lens element is R3, the radius of curvature of the image-side surface of the second lens element is R4, the on-axis thickness of the second lens element is d3, the total optical length of the image-capturing optical lens unit is TTL, and the following relationships are satisfied:

-6.02≤(R3+R4)/(R3-R4)≤-0.72；

0.02≤d3/TTL≤0.21。

4. the image-capturing optical lens of claim 1, wherein the focal length of the third lens is f3, the on-axis thickness of the third lens is d5, the total optical length of the image-capturing optical lens is TTL, and the following relationship is satisfied:

0.59≤f3/f≤1.95；

0.15≤(R5+R6)/(R5-R6)≤0.89；

0.06≤d5/TTL≤0.22。

5. the image-capturing optical lens unit according to claim 1, wherein the fourth lens element has a focal length f4, a radius of curvature of an object-side surface of the fourth lens element is R7, a radius of curvature of an image-side surface of the fourth lens element is R8, an on-axis thickness of the fourth lens element is d7, an optical total length of the image-capturing optical lens unit is TTL, and the following relationship is satisfied:

-4.34≤f4/f≤-1.27；

-2.24≤(R7+R8)/(R7-R8)≤1.02；

0.02≤d7/TTL≤0.08。

6. a camera optical lens according to claim 1, wherein the focal length of the fifth lens element is f5, the total optical length of the camera optical lens is TTL, and the following relationship is satisfied:

0.68≤f5/f≤2.80；

0.17≤(R9+R10)/(R9-R10)≤1.09；

0.03≤d9/TTL≤0.17。

7. the image-capturing optical lens unit according to claim 1, wherein the curvature radius of the object-side surface of the sixth lens element is R11, the curvature radius of the image-side surface of the sixth lens element is R12, the on-axis thickness of the sixth lens element is d11, the total optical length of the image-capturing optical lens unit is TTL, and the following relationships are satisfied:

1.20≤(R11+R12)/(R11-R12)≤6.22；

0.02≤d11/TTL≤0.19。

8. the imaging optical lens according to claim 1, wherein a combined focal length of the first lens and the second lens is f12, and the following relationship is satisfied: f12/f is not less than 13.40 and not more than-2.52.

9. An imaging optical lens according to claim 1, wherein the F-number of the aperture of the imaging optical lens is FNO, and the following relationship is satisfied: FNO is less than or equal to 2.41.