CN111025579B

CN111025579B - Image pickup optical lens

Info

Publication number: CN111025579B
Application number: CN201911373084.2A
Authority: CN
Inventors: 孙雯; 张磊; 崔元善
Original assignee: Chengrui Optics Changzhou Co Ltd
Current assignee: Chengrui Optics Changzhou Co Ltd
Priority date: 2019-12-27
Filing date: 2019-12-27
Publication date: 2021-12-14
Anticipated expiration: 2039-12-27
Also published as: CN111025579A

Abstract

The invention relates to the field of optical lenses, and discloses an image pickup optical lens, which sequentially comprises 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 curvature radius of the object-side surface of the third lens is R5, the curvature radius of the image-side surface of the third lens is R6, the on-axis distance from the image-side surface of the third lens to the object-side surface of the fourth lens is d6, 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 maximum field angle of the imaging optical lens is FOV, and the following relational expressions are satisfied: FOV is more than or equal to 100.00 degrees and less than or equal to 135.00 degrees; R5/R6 is more than or equal to 1.00 and less than or equal to 20.00; d6/d8 is more than or equal to 1.00 and less than or equal to 5.00. The imaging optical lens can obtain high imaging performance and low TTL.

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. A wide-angle imaging lens having excellent optical characteristics, being ultra-thin and having sufficient chromatic aberration correction is in demand.

Disclosure of Invention

In view of the above problems, an object of the present invention is to provide an imaging optical lens that can satisfy the requirements of ultra-thinning and wide angle while achieving high imaging performance.

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: 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 curvature radius of the object-side surface of the third lens is R5, the curvature radius of the image-side surface of the third lens is R6, the on-axis distance from the image-side surface of the third lens to the object-side surface of the fourth lens is d6, 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 maximum field angle of the imaging optical lens is FOV, and the following relational expressions are satisfied: FOV is more than or equal to 100.00 degrees and less than or equal to 135.00 degrees; R5/R6 is more than or equal to 1.00 and less than or equal to 20.00; d6/d8 is more than or equal to 1.00 and less than or equal to 5.00.

Preferably, the object-side surface of the first lens element is concave in the paraxial region, and the image-side surface of the first lens element is convex in the paraxial region; the focal length of the image pickup optical lens is f, the focal length of the first lens is f1, the curvature radius of the object side surface of the first lens is R1, the curvature radius of the image side surface of the first lens is R2, the on-axis thickness of the first lens is d1, the total optical length of the image pickup optical lens is TTL, and the following relational expression is satisfied: f1/f is not less than 15.05 and not more than-4.24; -8.21 ≤ (R1+ R2)/(R1-R2) ≤ 1.90; d1/TTL is more than or equal to 0.05 and less than or equal to 0.34.

Preferably, the imaging optical lens satisfies the following relation: f1/f is not less than 9.40 and not more than-5.29; (R1+ R2)/(R1-R2) is not more than 5.13 and not more than-2.37; d1/TTL is more than or equal to 0.07 and less than or equal to 0.28.

Preferably, the second lens object side surface is convex at the paraxial region; the focal length of the image pickup optical lens is f, the focal length of the second lens is f2, the curvature radius of the object side surface of the second lens is R3, the curvature radius of the image side surface of the second lens is R4, the on-axis thickness of the second lens is d3, the total optical length of the image pickup optical lens is TTL, and the following relational expression is satisfied: f2/f is more than or equal to 0.73 and less than or equal to 2.70; -2.71 ≤ (R3+ R4)/(R3-R4) ≤ 0.50; d3/TTL is more than or equal to 0.03 and less than or equal to 0.10.

Preferably, the imaging optical lens satisfies the following relation: f2/f is more than or equal to 1.17 and less than or equal to 2.16; -1.69 (R3+ R4)/(R3-R4) is less than or equal to-0.63; d3/TTL is more than or equal to 0.04 and less than or equal to 0.08.

Preferably, the object-side surface of the third lens element is concave in the paraxial region, and the image-side surface of the third lens element is convex in the paraxial region; the focal length of the image pickup optical lens is f, 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 pickup optical lens is TTL, and the following relational expression is satisfied: f3/f is more than or equal to 1.81 and less than or equal to 54.06; (R5+ R6)/(R5-R6) is not more than 0.55 and not more than 11.84; d5/TTL is more than or equal to 0.04 and less than or equal to 0.13.

Preferably, the imaging optical lens satisfies the following relation: f3/f is more than or equal to 2.90 and less than or equal to 43.25; (R5+ R6)/(R5-R6) is not more than 0.89 and not more than 9.47; d5/TTL is more than or equal to 0.06 and less than or equal to 0.10.

Preferably, the fourth lens object side surface is concave at the paraxial region; the focal length of the image pickup optical lens is f, the focal length of the fourth lens element is f4, the curvature radius of the object-side surface of the fourth lens element is R7, the curvature radius 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 relational expression is satisfied: f4/f is not less than 4.00 and not more than-0.97; -2.29 ≤ (R7+ R8)/(R7-R8) 0.72; d7/TTL is more than or equal to 0.02 and less than or equal to 0.07.

Preferably, the imaging optical lens satisfies the following relation: f4/f is not less than-1.21 and is not less than-2.50; -1.43 ≤ (R7+ R8)/(R7-R8) 0.57; d7/TTL is more than or equal to 0.03 and less than or equal to 0.05.

Preferably, the object-side surface of the fifth lens element is concave in the paraxial region, and the image-side surface thereof is convex in the paraxial region; the focal length of the image pickup optical lens is f, the focal length of the fifth lens element is f5, 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 thickness of the fifth lens element is d9, the total optical length of the image pickup optical lens is TTL, and the following relational expression is satisfied: f5/f is more than or equal to 0.31 and less than or equal to 1.51; (R9+ R10)/(R9-R10) is not more than 0.61 and not more than 2.08; d9/TTL is more than or equal to 0.07 and less than or equal to 0.25.

Preferably, the imaging optical lens satisfies the following relation: f5/f is more than or equal to 0.49 and less than or equal to 1.21; (R9+ R10)/(R9-R10) is not more than 0.97 and not more than 1.66; d9/TTL is more than or equal to 0.10 and less than or equal to 0.20.

Preferably, the object-side surface of the sixth lens element is convex in the paraxial region, and the image-side surface of the sixth lens element is concave in the paraxial region; the focal length of the imaging optical lens is f, the focal length of the sixth lens element is f6, 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 imaging optical lens is TTL, and the following relational expression is satisfied: f6/f is not less than 7.46 and not more than-0.54; 1.06 is not more than (R11+ R12)/(R11-R12) is not more than 7.35; d11/TTL is more than or equal to 0.03 and less than or equal to 0.10.

Preferably, the imaging optical lens satisfies the following relation: f6/f is not less than 4.66 and not more than-0.68; 1.69 is less than or equal to (R11+ R12)/(R11-R12) is less than or equal to 5.88; d11/TTL is more than or equal to 0.05 and less than or equal to 0.08.

Preferably, the total optical length TTL of the image pickup optical lens is less than or equal to 6.82 millimeters.

Preferably, the total optical length TTL of the image pickup optical lens is less than or equal to 6.51 millimeters.

Preferably, the F-number of the imaging optical lens is less than or equal to 2.16.

Preferably, the F-number of the imaging optical lens is less than or equal to 2.12.

The invention has the beneficial effects that: the imaging optical lens according to the present invention has excellent optical characteristics, is extremely thin, has a wide angle, and sufficiently corrects chromatic aberration, and is particularly suitable for a mobile phone imaging lens unit and a WEB imaging lens which are configured by an imaging element such as a CCD or a CMOS for high pixel.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments will be 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 shown in fig. 9.

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 image pickup optical lens 10 according to a first embodiment of the present invention, and the image pickup optical lens 10 includes seven 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 diaphragm S1, a second lens L2, 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 on the image side of the sixth lens element L6.

The maximum field angle of the entire imaging optical lens 10 is defined as FOV, and the following relational expression is satisfied: the FOV is more than or equal to 100.00 degrees and less than or equal to 135.00 degrees, the maximum field angle of the camera optical lens 10 is defined, ultra-wide-angle camera shooting can be realized within the range, and the user experience is improved.

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 1.00-20.00, and the shape of the third lens L3 is defined, so that the problem of chromatic aberration on the axis can be corrected favorably as the lens is in a range of ultra-thin wide angle. Preferably, 1.65. ltoreq. R5/R6. ltoreq.19.89 is satisfied.

Defining an on-axis distance d6 from an image-side surface of the third lens L3 to an object-side surface of the fourth lens L4, and 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, the following relations are satisfied: 1.00-d 6/d 8-5.00, and the ratio of the axial distance from the image-side surface of the third lens L3 to the object-side surface of the fourth lens L4 to the axial distance from the image-side surface of the fourth lens L4 to the object-side surface of the fifth lens L5 is defined, and when the ratio is within the range, the lens is favorably widened. Preferably, 1.04. ltoreq. d6/d 8. ltoreq.4.97.

When the focal length of the image pickup optical lens 10, the focal lengths of the respective lenses, the refractive indices of the respective lenses, the optical total length of the image pickup optical lens, the on-axis thickness, and the curvature radius satisfy the above-described relational expressions, the image pickup optical lens 10 can have high performance and meet the design requirement of low TTL.

In this embodiment, the object-side surface of the first lens element L1 is concave in the paraxial region thereof, and the image-side surface thereof is convex in the paraxial region thereof, and has negative refractive power.

The focal length of the entire image pickup optical lens 10 is f, and the focal length of the first lens L1 is f1, and the following relationships are satisfied: -15.05. ltoreq. f 1/f. ltoreq. 4.24, specifying the ratio of the focal length of the first lens L1 to the overall focal length. When the first lens element is within the specified range, the first lens element has appropriate negative refractive power, which is beneficial to reducing system aberration and is beneficial to the development of ultra-thinning and wide-angle lens. Preferably, it satisfies-9.40. ltoreq. f 1/f. ltoreq-5.29.

The curvature radius of the object side surface of the first lens L1 is R1, the curvature radius of the image side surface of the first lens L2 is R2, and the following relations are satisfied: 8.21 ≦ (R1+ R2)/(R1-R2) ≦ -1.90, and the shape of the first lens is appropriately controlled so that the first lens can effectively correct the system spherical aberration. Preferably, it satisfies-5.13 ≦ (R1+ R2)/(R1-R2) ≦ -2.3.

The on-axis thickness of the first lens L1 is d1, the total optical length of the imaging optical lens is TTL, and the following relational expression is satisfied: d1/TTL is more than or equal to 0.05 and less than or equal to 0.34, and ultra-thinning is facilitated. Preferably, 0.07. ltoreq. d 1/TTL. ltoreq.0.28.

In this embodiment, the object-side surface of the second lens element L2 is convex along the paraxial region thereof and has positive refractive power.

The focal length of the image pickup optical lens 10 is f, the focal length of the second lens L2 is f2, and the following relations are satisfied: f2/f is more than or equal to 0.73 and less than or equal to 2.70, and the positive focal power of the second lens L2 is controlled in a reasonable range, so that the aberration of the optical system can be corrected. Preferably, 1.17. ltoreq. f 2/f. ltoreq.2.16.

The curvature radius R3 of the object side surface of the second lens L2 and the curvature radius R4 of the image side surface of the second lens L2 satisfy the following relations: -2.71 ≦ (R3+ R4)/(R3-R4) ≦ -0.50, and defines the shape of the second lens L2, and is advantageous for correcting the problem of chromatic aberration on the axis as the lens advances to an ultra-thin wide angle within the range. Preferably, -1.69 ≦ (R3+ R4)/(R3-R4). ltoreq.0.63.

The on-axis thickness of the second lens L2 is d3, the total optical length of the imaging optical lens is TTL, and the following relational expression is satisfied: d3/TTL is more than or equal to 0.03 and less than or equal to 0.10, and ultra-thinning is facilitated. Preferably, 0.04. ltoreq. d 3/TTL. ltoreq.0.08.

In this embodiment, the object-side surface of the third lens element L3 is concave in the paraxial region thereof, and the image-side surface thereof is convex in the paraxial region thereof, and has positive refractive power.

The focal length of the entire image pickup optical lens 10 is f, the focal length of the third lens L3 is f3, and the following relationships are satisfied: 1.81 ≦ f3/f ≦ 54.06, and the system has better imaging quality and lower sensitivity through reasonable distribution of the focal power. Preferably, 2.90. ltoreq. f 3/f. ltoreq.43.25.

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 relations are satisfied: the (R5+ R6)/(R5-R6) is not less than 0.55 and not more than 11.84, the shape of the third lens L3 can be effectively controlled, the molding of the third lens L3 is facilitated, the deflection degree of light rays passing through the lens can be alleviated within the range specified by the conditional expression, and the aberration can be effectively reduced. Preferably, 0.89 ≦ (R5+ R6)/(R5-R6). ltoreq.9.47.

The on-axis thickness of the third lens L3 is d5, the total optical length of the imaging optical lens is TTL, and the following relational expression is satisfied: d5/TTL is more than or equal to 0.04 and less than or equal to 0.13, and ultra-thinning is facilitated. Preferably, 0.06. ltoreq. d 5/TTL. ltoreq.0.10.

In this embodiment, the object-side surface of the fourth lens element L4 is concave at the paraxial region and has negative refractive power.

The focal length of the entire image pickup optical lens 10 is f, and the focal length of the fourth lens L4 is f4, and the following relations are satisfied: 4.00 ≦ f4/f ≦ -0.97, allowing better imaging quality and lower sensitivity of the system through reasonable distribution of optical power. Preferably, -2.50. ltoreq. f 4/f. ltoreq-1.21.

The curvature radius R7 of the object side surface of the fourth lens L4 and the curvature radius R8 of the image side surface of the fourth lens L4 satisfy the following relations: -2.29 ≦ (R7+ R8)/(R7-R8) ≦ 0.72, and the shape of the fourth lens L4 is specified, and when the shape is within the range, problems such as aberration of the off-axis angle are easily corrected with the development of ultra-thin and wide-angle angles. Preferably, -1.43 ≦ (R7+ R8)/(R7-R8). ltoreq.0.57.

The on-axis thickness of the fourth lens L4 is d7, the total optical length of the imaging optical lens is TTL, and the following relational expression is satisfied: d7/TTL is more than or equal to 0.02 and less than or equal to 0.07, and ultra-thinning is facilitated. Preferably, 0.03. ltoreq. d 7/TTL. ltoreq.0.05.

In this embodiment, the object-side surface of the fifth lens element L5 is concave along the paraxial region thereof, and the image-side surface thereof is convex along the paraxial region thereof, and has positive refractive power.

The focal length of the entire image pickup optical lens 10 is f, and the focal length of the fifth lens L5 is f5, and the following relations are satisfied: f5/f is more than or equal to 0.31 and less than or equal to 1.51, and the definition of the fifth lens L5 can effectively make the light ray angle of the camera lens smooth and reduce the tolerance sensitivity. Preferably, 0.49. ltoreq. f 5/f. ltoreq.1.21.

The curvature radius R9 of the object side surface of the fifth lens L5 and the curvature radius R10 of the image side surface of the fifth lens L5 satisfy the following relations: the (R9+ R10)/(R9-R10) is not more than 0.61 and not more than 2.08, and the shape of the fifth lens L5 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, 0.97 ≦ (R9+ R10)/(R9-R10). ltoreq.1.66.

The on-axis thickness of the fifth lens L5 is d9, the total optical length of the imaging optical lens is TTL, and the following relational expression is satisfied: d9/TTL is more than or equal to 0.07 and less than or equal to 0.25, and ultra-thinning is facilitated. Preferably, 0.10. ltoreq. d 9/TTL. ltoreq.0.20.

In this embodiment, the object-side surface of the sixth lens element L6 is convex in the paraxial region thereof and the image-side surface thereof is concave in the paraxial region thereof, and has negative refractive power.

The focal length of the entire image pickup optical lens 10 is f, and the focal length of the sixth lens L6 is f6, and the following relationships are satisfied: 7.46 ≦ f6/f ≦ -0.54, allowing better imaging quality and lower sensitivity of the system through reasonable distribution of optical power. Preferably, -4.66. ltoreq. f 6/f. ltoreq-0.68.

The curvature radius R11 of the object side surface of the sixth lens L6 and the curvature radius R12 of the image side surface of the sixth lens L6 satisfy the following relations: 1.06 is not more than (R11+ R12)/(R11-R12) is not more than 7.35, 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, 1.69 ≦ (R11+ R12)/(R11-R12). ltoreq.5.88.

The on-axis thickness of the sixth lens L6 is d11, the total optical length of the imaging optical lens is TTL, and the following relational expression is satisfied: d11/TTL is more than or equal to 0.03 and less than or equal to 0.10, and ultra-thinning is facilitated. Preferably, 0.05. ltoreq. d 11/TTL. ltoreq.0.08.

In this embodiment, the total optical length TTL of the image pickup optical lens 10 is less than or equal to 6.82 mm, which is beneficial to achieving ultra-thinning. Preferably, the total optical length TTL of the image pickup optical lens 10 is less than or equal to 6.51 millimeters.

In the present embodiment, the number of apertures F of the imaging optical lens 10 is 2.16 or less. The large aperture is large, and the imaging performance is good. Preferably, the F-number of the imaging optical lens 10 is 2.12 or less.

With such a design, the total optical length TTL of the entire imaging optical lens 10 can be made as short as possible, and the characteristic of miniaturization can be maintained.

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 aspheric coefficients.

IH: image height

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

	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	1	0.555
P1R2	1	0.355
						P2R1	0
P2R2	0
						P3R1	0
P3R2	1	0.855
						P4R1	0
P4R2	4	0.295	0.875	1.135	1.165
						P5R1	2	0.895	1.145
P5R2	2	0.885	1.425
						P6R1	2	0.405	1.415
P6R2	1	0.505

[ TABLE 4 ]

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 13 shown later shows values of various numerical values in examples 1, 2, and 3 corresponding to the parameters specified in the conditional expressions.

As shown in table 13, the first embodiment satisfies each conditional expression.

In the present embodiment, the imaging optical lens has an entrance pupil diameter of 1.19mm, a full field image height of 2.91mm, a maximum field angle of 101.00 ° and is wide-angle and ultra-thin, and has excellent optical characteristics with its 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 ]

[ TABLE 8 ]

	Number of stagnation points	Location of stagnation 1	Location of stagnation 2
				P1R1	1	2.065
P1R2	1	0.865
				P2R1	0
P2R2	1	0.515
				P3R1	0
P3R2	0
				P4R1	0
P4R2	0
				P5R1	2	0.385	0.745
P5R2	0
				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 13, the second embodiment satisfies each conditional expression.

In the present embodiment, the imaging optical lens has an entrance pupil diameter of 0.906mm, a full field image height of 2.91mm, a maximum field angle of 120.00 °, a wide angle, and a high profile, and has excellent optical characteristics with the on-axis and off-axis chromatic aberration thereof 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	Position of reverse curve 4
						P1R1	1	0.975
P1R2	1	0.445
						P2R1	0
P2R2	1	0.205
						P3R1	0
P3R2	1	0.755
						P4R1	0
P4R2	3	0.275	0.755	1.095
						P5R1	4	0.195	0.435	0.845	1.195
P5R2	1	0.705
						P6R1	3	0.565	1.665	2.255
P6R2	3	0.595	2.255	2.485

[ TABLE 12 ]

	Number of stagnation points	Location of stagnation 1	Location of stagnation 2	Location of stagnation 3
					P1R1	1	2.505
P1R2	1	0.825
					P2R1	0
P2R2	1	0.325
					P3R1	0
P3R2	0
					P4R1	0
P4R2	3	0.525	0.975	1.145
					P5R1	2	1.035	1.235
P5R2	0
					P6R1	3	1.335	2.055	2.355
P6R2	1	1.745

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 13 below shows the numerical values corresponding to the respective conditional expressions in the present embodiment, in accordance with the conditional expressions described above. 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 0.744mm, a full field image height of 2.91mm, a maximum field angle of 134.40 ° and a wide and ultra-thin profile, and has excellent optical characteristics with sufficiently corrected on-axis and off-axis chromatic aberration.

[ TABLE 13 ]

Parameter and condition formula	Example 1	Example 2	Example 3
				f	2.345	1.811	1.563
f1	-17.643	-13.413	-9.930
				f2	3.434	2.684	2.814
f3	8.492	65.274	6.501
				f4	-4.377	-3.622	-2.273
f5	1.438	1.561	1.578
				f6	-1.915	-3.579	-5.832
f12	3.768	2.594	2.690
				FNO	1.97	2.00	2.10
FOV	101.00	120.00	134.40
				R5/R6	19.78	1.29	3.59
d6/d8	1.08	4.94	1.33

FNO is the F-number of the stop of the image pickup optical lens, and F12 is the combined focal length of the first lens and the second 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 object side surface of the first lens is a concave surface at the paraxial position, and the image side surface of the first lens is a convex surface at the paraxial position; the object side surface of the second lens is convex at the paraxial part; the object side surface of the third lens is a concave surface at the paraxial part, and the image side surface of the third lens is a convex surface at the paraxial part; the object side surface of the fourth lens is a concave surface at the paraxial part; the object side surface of the fifth lens is a concave surface at the paraxial position, and the image side surface of the fifth lens is a convex surface at the paraxial position; the object side surface of the sixth lens is a convex surface at the paraxial region, and the image side surface of the sixth lens is a concave surface at the paraxial region;

the curvature radius of the object-side surface of the third lens is R5, the curvature radius of the image-side surface of the third lens is R6, the on-axis distance from the image-side surface of the third lens to the object-side surface of the fourth lens is d6, 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 maximum field angle of the imaging optical lens is FOV, and the following relational expressions are satisfied:

100.00°≤FOV≤135.00°；

1.00≤R5/R6≤20.00；

1.00≤d6/d8≤5.00。

2. the imaging optical lens of claim 1, wherein the focal length of the imaging optical lens is f, the focal length of the first lens is f1, the radius of curvature of the object-side surface of the first lens is R1, the radius of curvature of the image-side surface of the first lens is R2, the on-axis thickness of the first lens is d1, the total optical length of the imaging optical lens is TTL, and the following relationships are satisfied:

-15.05≤f1/f≤-4.24；

-8.21≤(R1+R2)/(R1-R2)≤-1.90；

0.05≤d1/TTL≤0.34。

3. the imaging optical lens according to claim 2, wherein the imaging optical lens satisfies the following relationship:

-9.40≤f1/f≤-5.29；

-5.13≤(R1+R2)/(R1-R2)≤-2.37；

0.07≤d1/TTL≤0.28。

4. the imaging optical lens of claim 1, wherein the focal length of the imaging optical lens is f, the focal length of the second lens is f2, the radius of curvature of the object-side surface of the second lens is R3, the radius of curvature of the image-side surface of the second lens is R4, the on-axis thickness of the second lens is d3, the total optical length of the imaging optical lens is TTL, and the following relationships are satisfied:

0.73≤f2/f≤2.70；

-2.71≤(R3+R4)/(R3-R4)≤-0.50；

0.03≤d3/TTL≤0.10。

5. the imaging optical lens according to claim 4, wherein the imaging optical lens satisfies the following relation:

1.17≤f2/f≤2.16；

-1.69≤(R3+R4)/(R3-R4)≤-0.63；

0.04≤d3/TTL≤0.08。

6. the image-capturing optical lens of claim 1, wherein the focal length of the image-capturing optical lens is f, 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:

1.81≤f3/f≤54.06；

0.55≤(R5+R6)/(R5-R6)≤11.84；

0.04≤d5/TTL≤0.13。

7. the imaging optical lens according to claim 6, wherein the imaging optical lens satisfies the following relation:

2.90≤f3/f≤43.25；

0.89≤(R5+R6)/(R5-R6)≤9.47；

0.06≤d5/TTL≤0.10。

8. the imaging optical lens of claim 1, wherein the focal length of the imaging optical lens is f, the focal length of the fourth lens is f4, the radius of curvature of the object-side surface of the fourth lens is R7, the radius of curvature of the image-side surface of the fourth lens is R8, the on-axis thickness of the fourth lens is d7, the total optical length of the imaging optical lens is TTL, and the following relationships are satisfied:

-4.00≤f4/f≤-0.97；

-2.29≤(R7+R8)/(R7-R8)≤0.72；

0.02≤d7/TTL≤0.07。

9. the image-pickup optical lens according to claim 8, wherein the image-pickup optical lens satisfies the following relation:

-2.50≤f4/f≤-1.21；

-1.43≤(R7+R8)/(R7-R8)≤0.57；

0.03≤d7/TTL≤0.05。

10. the imaging optical lens of claim 1, wherein the focal length of the imaging optical lens is f, the focal length of the fifth lens is f5, the radius of curvature of the object-side surface of the fifth lens is R9, the radius of curvature of the image-side surface of the fifth lens is R10, the on-axis thickness of the fifth lens is d9, the total optical length of the imaging optical lens is TTL, and the following relationships are satisfied:

0.31≤f5/f≤1.51；

0.61≤(R9+R10)/(R9-R10)≤2.08；

0.07≤d9/TTL≤0.25。

11. the image-pickup optical lens according to claim 10, wherein the image-pickup optical lens satisfies the following relation:

0.49≤f5/f≤1.21；

0.97≤(R9+R10)/(R9-R10)≤1.66；

0.10≤d9/TTL≤0.20。

12. the imaging optical lens of claim 1, wherein the focal length of the imaging optical lens is f, the focal length of the sixth lens is f6, the radius of curvature of the object-side surface of the sixth lens is R11, the radius of curvature of the image-side surface of the sixth lens is R12, the on-axis thickness of the sixth lens is d11, the total optical length of the imaging optical lens is TTL, and the following relationships are satisfied:

-7.46≤f6/f≤-0.54；

1.06≤(R11+R12)/(R11-R12)≤7.35；

0.03≤d11/TTL≤0.10。

13. the image-pickup optical lens according to claim 12, wherein the image-pickup optical lens satisfies the following relation:

-4.66≤f6/f≤-0.68；

1.69≤(R11+R12)/(R11-R12)≤5.88；

0.05≤d11/TTL≤0.08。

14. a camera optical lens according to claim 1, characterized in that the total optical length TTL of the camera optical lens is less than or equal to 6.82 mm.

15. A camera optical lens according to claim 14, characterized in that the total optical length TTL of the camera optical lens is less than or equal to 6.51 mm.

16. A camera optical lens according to claim 1, characterized in that the F-number of the aperture of the camera optical lens is less than or equal to 2.16.

17. A camera optical lens according to claim 16, characterized in that the F-number of the aperture of the camera optical lens is less than or equal to 2.12.