CN114137698A - Image pickup optical lens - Google Patents

Abstract

The invention relates to the field of optical lenses, and discloses an image pickup optical lens, which comprises three lenses in sequence from an object side to an image side: a first lens element with positive refractive power, a second lens element with negative refractive power, and a third lens element with positive refractive power; the focal length of the imaging 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 third lens is f3, the central curvature radius of the object-side surface of the second lens is R3, the central curvature radius of the image-side surface of the second lens is R4, the on-axis thickness of the first lens is d1, the on-axis thickness of the second lens is d3, the on-axis distance from the image-side surface of the second lens to the object-side surface of the third lens is d4, and the on-axis thickness of the third lens is d5, and the relation is satisfied: f1/f is more than or equal to 0.72 and less than or equal to 0.90; f2/f is more than or equal to-0.85 and less than or equal to-0.65; f3/f is more than or equal to 1.00 and less than or equal to 1.20; R4/R3 is more than or equal to 2.50 and less than or equal to 6.00; d1/d3 is more than or equal to 1.50 and less than or equal to 2.50; d5/d4 is more than or equal to 2.00 and less than or equal to 6.00. The camera optical lens has good optical performance and meets the design requirements of 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 various smart devices, the demand for miniaturized photographing optical lenses is increasing, and due to the reduction of the pixel size of the photosensitive device and the trend of the electronic products to have a good function and a light, thin and portable appearance, the miniaturized photographing optical lenses with good imaging quality are the mainstream in the market. In order to obtain better imaging quality, a multi-lens structure is often adopted. Moreover, with the development of technology and the increase of diversified demands of users, under the condition that the pixel area of the photosensitive device is continuously reduced and the requirement of the system on the imaging quality is continuously improved, the three-piece lens structure appears in the design of the lens. A wide-angle imaging lens having excellent optical characteristics, small distortion, and sufficiently corrected aberrations is strongly required.

Disclosure of Invention

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

To solve the above-mentioned problems, an embodiment of the present invention provides an imaging optical lens, which includes three lenses, in order from an object side to an image side: a first lens element with positive refractive power, a second lens element with negative refractive power, and a third lens element with positive refractive power; the focal length of the imaging 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 third lens is f3, the central curvature radius of the object-side surface of the second lens is R3, the central curvature radius of the image-side surface of the second lens is R4, the on-axis thickness of the first lens is d1, the on-axis thickness of the second lens is d3, the on-axis distance from the image-side surface of the second lens to the object-side surface of the third lens is d4, the on-axis thickness of the third lens is d5, and the following relations are satisfied: f1/f is more than or equal to 0.72 and less than or equal to 0.90; f2/f is more than or equal to-0.85 and less than or equal to-0.65; f3/f is more than or equal to 1.00 and less than or equal to 1.20; R4/R3 is more than or equal to 2.50 and less than or equal to 6.00; d1/d3 is more than or equal to 1.50 and less than or equal to 2.50; d5/d4 is more than or equal to 2.00 and less than or equal to 6.00.

Optionally, a central radius of curvature of the object-side surface of the third lens is R5, a central radius of curvature of the image-side surface of the third lens is R6, and the following relationships are satisfied: R6/R5 is more than or equal to 1.50 and less than or equal to 3.50.

Optionally, an object-side surface of the first lens element is convex at a paraxial region, and an image-side surface of the first lens element is convex at a paraxial region; the center curvature radius of the object side surface of the first lens is R1, the center curvature radius of the image side surface of the first lens is R2, the total optical length of the image pickup optical lens is TTL, and the following relational expression is satisfied: -1.54 ≤ (R1+ R2)/(R1-R2) is ≤ 0.07; d1/TTL is more than or equal to 0.09 and less than or equal to 0.31.

Optionally, an object-side surface of the second lens element is concave at a paraxial region, and an image-side surface of the first lens element is convex at the paraxial region; the total optical length of the shooting optical lens is TTL and meets the following relational expression: -4.51 ≤ (R3+ R4)/(R3-R4) ≤ 0.93; d3/TTL is more than or equal to 0.04 and less than or equal to 0.18.

Optionally, an object-side surface of the third lens element is convex at a paraxial region, and an image-side surface of the first lens element is concave at the paraxial region; the central curvature radius of the object side surface of the third lens is R5, the central curvature radius of the image side surface of the third lens is R6, the total optical length of the photographic optical lens is TTL, and the following relational expression is satisfied: 9.70-1.20 of (R5+ R6)/(R5-R6); d5/TTL is more than or equal to 0.09 and less than or equal to 0.50.

Optionally, a combined focal length of the first lens and the second lens is f12, and the following relation is satisfied: f12/f is more than or equal to 1.07 and less than or equal to 5.58.

Optionally, the total optical length of the image pickup optical lens is TTL, the image height of the image pickup optical lens is IH, and the following relation is satisfied: TTL/IH is less than or equal to 1.64.

Optionally, the field angle of the image pickup optical lens is FOV, and satisfies the following relation: the FOV is more than or equal to 75.00 degrees.

Optionally, the aperture value of the image pickup optical lens is FNO, and satisfies the following relation: FNO is less than or equal to 2.55.

The invention has the beneficial effects that: the imaging optical lens according to the present invention has excellent optical characteristics, has a wide angle of view and is made thinner, and is particularly suitable for a mobile phone imaging lens unit and a WEB imaging lens including an imaging element such as a high-pixel CCD or a CMOS.

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 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;

fig. 17 is a schematic configuration diagram of an imaging optical lens according to a fifth embodiment of the present invention;

fig. 18 is a schematic view of axial aberrations of the image pickup optical lens shown in fig. 17;

fig. 19 is a schematic diagram of chromatic aberration of magnification of the imaging optical lens shown in fig. 17;

fig. 20 is a schematic view of curvature of field and distortion of the imaging optical lens shown in fig. 17;

fig. 21 is a schematic configuration diagram of an imaging optical lens according to a sixth embodiment of the present invention;

fig. 22 is a schematic view of axial aberrations of the image pickup optical lens shown in fig. 21;

fig. 23 is a schematic diagram of chromatic aberration of magnification of the imaging optical lens shown in fig. 21;

fig. 24 is a schematic view of curvature of field and distortion of the imaging optical lens shown in fig. 21;

fig. 25 is a schematic configuration diagram of an image pickup optical lens of a comparative embodiment;

fig. 26 is a schematic view of axial aberrations of the image pickup optical lens shown in fig. 25;

fig. 27 is a schematic diagram of chromatic aberration of magnification of the imaging optical lens shown in fig. 25;

fig. 28 is a schematic view of curvature of field and distortion of the imaging optical lens shown in fig. 25.

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 three lenses. Specifically, the image capturing optical lens system 10, in order from an object side to an image side: a diaphragm S1, a first lens L1, a second lens L2, and a third lens L3. An optical element such as an optical filter (filter) GF may be disposed between the third lens L3 and the image plane Si.

In this embodiment, the first lens L1, the second lens L2 and the third lens L3 are made of plastic materials. In other alternative embodiments, each lens may be made of other materials.

In the present embodiment, 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, and the following relational expression is satisfied: f1/f is more than or equal to 0.72 and less than or equal to 0.90, the ratio of the focal length f1 of the first lens L1 to the focal length f of the shooting optical lens 10 is regulated, the curvature of field of the shooting optical lens 10 can be effectively balanced, and the curvature of field offset of the central field of view is smaller than 0.02 mm.

The focal length of the image pickup optical lens 10 is f, the focal length of the second lens L2 is defined as f2, and the following relation is satisfied: f2/f is more than or equal to 0.85 and less than or equal to-0.65, the ratio of the focal length f2 of the second lens L2 to the focal length f of the shooting optical lens 10 is specified, and the shooting optical lens 10 has better imaging quality and lower sensitivity through reasonable distribution of the focal lengths.

The focal length of the image pickup optical lens 10 is f, the focal length of the third lens L3 is defined as f3, and the following relation is satisfied: f3/f is more than or equal to 1.00 and less than or equal to 1.20, the ratio of the focal length f3 of the third lens L3 to the focal length f of the image pickup optical lens 10 is specified, and the image pickup optical lens 10 has better imaging quality and lower sensitivity through reasonable distribution of the focal lengths.

The central curvature radius of the object side surface of the second lens L2 is defined as R3, the central curvature radius of the image side surface of the second lens L2 is defined as R4, and the following relations are satisfied: R4/R3 of 2.50-6.00, the shape of the second lens L2 is regulated, which is beneficial to correcting astigmatism and Distortion of the shooting optical lens 10, so that Distortion is less than or equal to 18.00 percent, and the possibility of generating a dark angle is reduced.

Defining the on-axis thickness of the first lens L1 as d1 and the on-axis thickness of the second lens L2 as d3, the following relations are satisfied: 1.50 is not less than d1/d3 is not less than 2.50, the ratio of the on-axis thickness d1 of the first lens L1 to the on-axis thickness d3 of the second lens L2 is specified, and the optical total length is compressed within the conditional expression range, so that the ultrathin effect is realized.

Defining an on-axis distance d4 from an image-side surface of the second lens L2 to an object-side surface of the third lens L3, an on-axis thickness d5 of the third lens L3, the following relationship is satisfied: 2.00 < d5/d4 < 6.00, and the ratio of the on-axis thickness d5 of the third lens L3 to the on-axis distance d4 from the image-side surface of the second lens L2 to the object-side surface of the third lens L3 is defined, which contributes to the compression of the optical total length and the realization of the ultrathin effect within the conditional expression.

The central curvature radius of the object side surface of the third lens L3 is defined as R5, the central curvature radius of the image side surface of the third lens L3 is defined as R6, and the following relations are satisfied: R6/R5 is more than or equal to 1.50 and less than or equal to 3.50, the shape of the third lens L3 is defined, the deflection degree of light is reduced, and chromatic aberration is effectively corrected, so that the chromatic aberration LC is less than or equal to 2.00 mu m.

In this embodiment, the first lens element L1 with positive refractive power has a convex object-side surface and a convex image-side surface. In other alternative embodiments, the object-side surface and the image-side surface of the first lens L1 may be arranged in other concave and convex distribution.

The central curvature radius of the object side surface of the first lens L1 is defined as R1, the central curvature radius of the image side surface of the first lens L1 is defined as R2, and the following relational expressions are satisfied: 1.54 ≦ (R1+ R2)/(R1-R2) ≦ -0.07, and the shape of the first lens L1 is controlled appropriately so that the first lens L1 can correct the system spherical aberration effectively. Preferably, it satisfies-0.96 ≦ (R1+ R2)/(R1-R2) ≦ -0.09.

The total optical length of the imaging optical lens 10 is TTL, the on-axis thickness of the first lens L1 is defined as d1, and the following relational expression is satisfied: d1/TTL is more than or equal to 0.09 and less than or equal to 0.31, and ultra-thinning is facilitated in the conditional expression range. Preferably, 0.14. ltoreq. d 1/TTL. ltoreq.0.25 is satisfied.

In this embodiment, the second lens element L2 with negative refractive power has a concave object-side surface and a convex image-side surface. In other alternative embodiments, the object-side surface and the image-side surface of the second lens L2 may be arranged in other concave and convex distribution.

The central curvature radius of the object side surface of the second lens L2 is R3, the central curvature radius of the image side surface of the second lens L2 is defined as R4, and the following relational expression is satisfied: -4.51 ≦ (R3+ R4)/(R3-R4) ≦ -0.93, 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 becomes thinner and wider in angle when in the range. Preferably, it satisfies-2.82 ≦ (R3+ R4)/(R3-R4) ≦ -1.17.

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 0.04 and less than or equal to 0.18, and ultra-thinning is facilitated in the condition formula range. Preferably, 0.06. ltoreq. d 3/TTL. ltoreq.0.14 is satisfied.

In this embodiment, the third lens element L3 with positive refractive power has a convex object-side surface and a concave image-side surface. In other alternative embodiments, the object side and the image side can be arranged in other concave and convex distribution.

The central curvature radius of the object side surface of the third lens L3 is R5, the central curvature radius of the image side surface of the third lens L3 is R6, and the following relational expression is satisfied: 9.70 ≦ (R5+ R6)/(R5-R6) ≦ -1.20, the shape of the third lens L3 is defined, which is beneficial to the formation of the third lens L3, and the deflection degree of the light passing through the lens can be alleviated within the range defined by the conditional expression, thereby effectively reducing the aberration. Preferably, it satisfies-6.06 ≦ (R5+ R6)/(R5-R6). ltoreq.1.15.

The total optical length of the imaging optical lens 10 is TTL, and the on-axis thickness of the third lens L3 is d5, which satisfies the following relation: d5/TTL is more than or equal to 0.09 and less than or equal to 0.50, and ultra-thinning is facilitated within the range of conditional expressions. Preferably, 0.15. ltoreq. d 5/TTL. ltoreq.0.40 is satisfied.

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 relation: f12/f is more than or equal to 1.07 and less than or equal to 5.58, and within the range of the conditional expression, 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, so as to keep the miniaturization of the image lens system. Preferably, 1.71. ltoreq. f 12/f. ltoreq.4.47 is satisfied.

In the present embodiment, the aperture value of the imaging optical lens 10 is defined as FNO, and the following relationship is satisfied: FNO is less than or equal to 2.55, so that a large aperture is realized, and the imaging performance of the photographic optical lens 10 is good. Preferably, FNO is less than or equal to 2.50.

In the present embodiment, the field angle of the imaging optical lens 10 is defined as FOV, and the following relational expression is satisfied: the FOV is more than or equal to 75.00 degrees, thereby realizing wide angle.

In this embodiment, the total optical length of the image pickup optical lens 10 is TTL, and the image height of the image pickup optical lens 10 is IH, which satisfy the following relation: TTL/IH is less than or equal to 1.64, thereby being beneficial to realizing ultra-thinning.

The imaging optical lens 10 has good optical performance and can meet the design requirements of wide angle and ultra-thinness; in accordance with the characteristics of the imaging optical lens 10, the imaging optical lens 10 is particularly suitable for a mobile phone imaging lens module and a WEB imaging lens which are configured by an imaging element such as a high-pixel CCD or 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, center curvature radius, on-axis thickness, position of the reverse curvature point and the position of the 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 Si) is in mm;

aperture value FNO: is the ratio of the effective focal length and the entrance pupil diameter of the imaging optical lens.

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: a radius of curvature at the center of the optical surface;

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

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

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

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

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

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

r7: the central radius of curvature of the object side of the optical filter GF;

r8: the center radius of curvature of the image side of the optical filter GF;

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

d 7: on-axis thickness of the optical filter GF;

d 8: the axial distance from the image side surface of the optical filter GF to the image surface Si;

nd: refractive index of d-line (d-line is green light with wavelength of 550 nm);

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;

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;

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 ]

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

z＝(cr²)/{1+[1-(k+1)(c²r²)]^1/2}+A4r⁴+A6r⁶+A8r⁸+A10r¹⁰+A12r¹²+A14r¹⁴+A16r¹⁶+A18r¹⁸+A20r²⁰ (1)

Where k is a conic coefficient, a4, a6, A8, a10, a12, a14, a16, a18, a20 are aspheric coefficients, c is a curvature at the center of the optical surface, r is a perpendicular distance from a point on an aspheric curve to the optical axis, and z is an aspheric depth (a perpendicular distance between a point on an aspheric surface at a distance of r from the optical axis and a tangent plane tangent to a vertex on the aspheric optical axis).

Tables 3 and 4 show the inflected point and stagnation point design data of each lens in the imaging optical lens 10 according to the first embodiment of the present invention. Wherein, 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, and P3R1 and P3R2 represent the object side surface and the image side surface of the third lens L3. 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
					P1R1	1	0.375	/	/
P1R2
		0	/	/	/
P2R1
		1	0.375	/	/
P2R2
		1	0.385	/	/
P3R1						3	0.245	1.025	1.115
	P3R2	2	0.355	1.425	/

[ TABLE 4 ]

	Number of stagnation points	Location of stagnation 1
			P1R1	0	/
P1R2	0	/
			P2R1	0	/
P2R2	1	0.535
			P3R1	1	0.745
P3R2	1	0.745

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 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 29 shown later shows values corresponding to the parameters specified in the conditional expressions for the respective numerical values in the first, second, third, fourth, fifth, and sixth embodiments and the comparative embodiment.

As shown in table 29, the first embodiment satisfies each conditional expression.

In the present embodiment, the imaging optical lens 10 has an entrance pupil diameter ENPD of 0.883mm, a full field image height IH of 1.750mm, and a diagonal field angle FOV of 78.00 °, and the imaging optical lens 10 satisfies the design requirements of a wide angle and a slim size, and has excellent optical characteristics with on-axis and off-axis chromatic aberration sufficiently corrected.

(second embodiment)

Fig. 5 shows an imaging optical lens 20 according to a second embodiment of the present invention, which is basically the same as the first embodiment, and the same reference numerals as the first embodiment, except for the differences 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
				P1R1	1	0.325	/
P1R2	0	/	/
				P2R1	1	0.395	/
P2R2	1	0.395	/
				P3R1	2	0.225	0.865
P3R2	1	0.375	/

[ TABLE 8 ]

	Number of stagnation points	Location of stagnation 1
			P1R1	0	/
P1R2	0	/
			P2R1	0	/
P2R2	1	0.545
			P3R1	1	0.485
P3R2	1	0.825

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. The field curvature S in fig. 8 is a field curvature in the sagittal direction, and T is a field curvature in the tangential direction.

As shown in table 29, the second embodiment satisfies each conditional expression.

In the present embodiment, the imaging optical lens 20 has an entrance pupil diameter ENPD of 0.764mm, a full field image height IH of 1.750mm, and a diagonal field angle FOV of 77.00 °, and the imaging optical lens 20 satisfies the design requirements of a wide angle and a slim size, and has excellent optical characteristics with on-axis and off-axis chromatic aberration sufficiently corrected.

(third embodiment)

Fig. 9 shows an imaging optical lens 30 according to a third embodiment of the present invention, which is basically the same as the first embodiment, has the same reference numerals as the first embodiment, and only differences 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
				P1R1	1	0.405	/
P1R2	0	/	/
				P2R1	2	0.435	0.465
P2R2	1	0.415	/
				P3R1	4	0.275	0.765
P3R2	1	0.445	/

[ TABLE 12 ]

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. The field curvature S in fig. 12 is a field curvature in the sagittal direction, and T is a field curvature in the tangential direction.

The following table 29 shows the numerical values corresponding to the respective conditional expressions in the present embodiment in accordance with the conditional expressions. Obviously, the imaging optical lens 30 of the present embodiment satisfies the above conditional expressions.

In the present embodiment, the imaging optical lens 30 has an entrance pupil diameter ENPD of 0.823mm, a full field height IH of 1.750mm, and a diagonal field angle FOV of 77.00 °, and the imaging optical lens 30 satisfies the design requirements of a wide angle and a slim size, and has excellent optical characteristics with on-axis and off-axis chromatic aberration sufficiently corrected.

(fourth embodiment)

Fig. 13 shows an imaging optical lens 40 according to a fourth embodiment of the present invention, which is basically the same as the first embodiment, has the same reference numerals as the first embodiment, and only differences 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
				P1R1	0	/	/
P1R2	0	/	/
				P2R1	0	/	/
P2R2	1	0.415	/
				P3R1	2	0.255	0.965
P3R2	1	0.475	/

[ TABLE 16 ]

	Number of stagnation points	Location of stagnation 1
			P1R1	0	/
P1R2	0	/
			P2R1	0	/
P2R2	1	0.555
			P3R1	1	0.535
P3R2	1	0.855

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. The field curvature S in fig. 16 is a field curvature in the sagittal direction, and T is a field curvature in the tangential direction.

The following table 29 shows the numerical values corresponding to the respective conditional expressions in the present embodiment in accordance with the conditional expressions. Obviously, the imaging optical lens 40 of the present embodiment satisfies the above conditional expressions.

In the present embodiment, the imaging optical lens 40 has an entrance pupil diameter ENPD of 0.796mm, a full field image height IH of 1.750mm, and a diagonal field angle FOV of 75.00 °, and the imaging optical lens 40 satisfies the design requirements of a wide angle and a slim size, and has excellent optical characteristics with on-axis and off-axis chromatic aberration sufficiently corrected.

(fifth embodiment)

Fig. 17 shows an imaging optical lens 50 according to a fifth embodiment of the present invention, which is basically the same as the first embodiment, has the same reference numerals as the first embodiment, and only differences will be described below.

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

[ TABLE 17 ]

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

[ TABLE 18 ]

Tables 19 and 20 show the inflection points and the stagnation point design data of each lens in the imaging optical lens 50 according to the fifth embodiment of the present invention.

[ TABLE 19 ]

	Number of points of inflection	Position of reverse curvature 1	Position of reverse curvature 2
				P1R1	1	0.405	/
P1R2	0	/	/
				P2R1	1	0.415	/
P2R2	1	0.395	/
				P3R1	2	0.265	0.675
P3R2	1	0.445	/

[ TABLE 20 ]

	Number of stagnation points	Location of standing pointDevice 1
			P1R1	0	/
P1R2	0	/
			P2R1	0	/
P2R2	1	0.555
			P3R1	0	/
P3R2	1	1.035

Fig. 18 and 19 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 50 according to the fifth embodiment. Fig. 20 is a schematic view showing curvature of field and distortion of light having a wavelength of 555nm after passing through the imaging optical lens 50 according to the fifth embodiment. The field curvature S in fig. 20 is a field curvature in the sagittal direction, and T is a field curvature in the tangential direction.

The following table 29 shows the numerical values corresponding to the respective conditional expressions in the present embodiment in accordance with the conditional expressions. Obviously, the imaging optical lens 50 of the present embodiment satisfies the above conditional expressions.

In the present embodiment, the imaging optical lens 50 has an entrance pupil diameter ENPD of 0.835mm, a full field image height IH of 1.750mm, and a diagonal field angle FOV of 77.00 °, and the imaging optical lens 50 satisfies the design requirements of a wide angle and a slim size, and has excellent optical characteristics with on-axis and off-axis chromatic aberration sufficiently corrected.

(sixth embodiment)

Fig. 21 shows an imaging optical lens 60 according to a sixth embodiment of the present invention, which is basically the same as the first embodiment, has the same reference numerals as the first embodiment, and only differences will be described below.

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

[ TABLE 21 ]

Table 22 shows aspherical surface data of each lens in the imaging optical lens 60 according to the sixth embodiment of the present invention.

[ TABLE 22 ]

Tables 23 and 24 show the inflection points and stagnation point design data of each lens in the imaging optical lens 60 according to the sixth embodiment of the present invention.

[ TABLE 23 ]

	Number of points of inflection	Position of reverse curvature 1	Position of reverse curvature 2
				P1R1	0	/	/
P1R2	0	/	/
				P2R1	0	/	/
P2R2	1	0.445	/
				P3R1	2	0.335	1.235
P3R2	1	0.415	/

[ TABLE 24 ]

	Number of stagnation points	Location of stagnation 1
			P1R1	0	/
P1R2	0	/
			P2R1	0	/
P2R2	1	0.595
			P3R1	1	0.855
P3R2	1	0.945

Fig. 22 and 23 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 60 according to the sixth embodiment. Fig. 24 is a schematic view showing curvature of field and distortion of light having a wavelength of 555nm after passing through the imaging optical lens 60 according to the sixth embodiment. The field curvature S in fig. 24 is a field curvature in the sagittal direction, and T is a field curvature in the tangential direction.

The following table 29 shows the numerical values corresponding to the respective conditional expressions in the present embodiment in accordance with the conditional expressions. Obviously, the imaging optical lens 60 of the present embodiment satisfies the above conditional expressions.

In the present embodiment, the imaging optical lens 60 has an entrance pupil diameter ENPD of 0.778mm, a full field height IH of 1.750mm, and a diagonal field angle FOV of 75.00 °, and the imaging optical lens 60 satisfies the design requirements of a wide angle and a slim size, and has excellent optical characteristics with on-axis and off-axis chromatic aberration sufficiently corrected.

(comparative embodiment)

Fig. 25 shows an imaging optical lens 70 according to a comparative embodiment, which is basically the same as the first embodiment, and the same reference numerals as the first embodiment, and only different points will be described below.

Tables 25 and 26 show design data of the imaging optical lens 70 according to the comparative embodiment.

[ TABLE 25 ]

Table 26 shows aspherical surface data of each lens in the imaging optical lens 70 of the comparative embodiment.

[ TABLE 26 ]

Tables 27 and 28 show the inflection point and stagnation point design data of each lens in the imaging optical lens 70 according to the comparative embodiment.

[ TABLE 27 ]

	Number of points of inflection	Position of reverse curvature 1	Position of reverse curvature 2
				P1R1	0	/	/
P1R2	0	/	/
				P2R1	0	/	/
P2R2	1	0.455	/
				P3R1	1	0.145	/
P3R2	2	0.535	1.345

[ TABLE 28 ]

	Number of stagnation points	Location of stagnation 1
			P1R1	0	/
P1R2	0	/
			P2R1	0	/
P2R2	0	/
			P3R1	1	0.275
P3R2	1	0.825

Fig. 26 and 27 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 70 according to the comparative embodiment. FIG. 28 is a schematic view showing curvature of field and distortion of light having a wavelength of 555nm after passing through the imaging optical lens 70 according to the comparative embodiment. The field curvature S in fig. 28 is a field curvature in the sagittal direction, and T is a field curvature in the tangential direction.

The following table 29 shows the numerical values corresponding to the respective conditional expressions in the comparative embodiment in accordance with the above conditional expressions. Obviously, the imaging optical lens 70 of the comparative embodiment does not satisfy the conditional expression: f1/f is more than or equal to 0.72 and less than or equal to 0.90.

In the comparative embodiment, the entrance pupil diameter ENPD of the imaging optical lens 70 is 0.714mm, the full field image height IH is 1.750mm, and the field angle FOV in the diagonal direction is 70.00 °, and the imaging optical lens 70 does not satisfy the design requirements of widening the angle and reducing the thickness.

[ TABLE 29 ]

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 (9)

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

the focal length of the imaging 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 third lens is f3, the central curvature radius of the object-side surface of the second lens is R3, the central curvature radius of the image-side surface of the second lens is R4, the on-axis thickness of the first lens is d1, the on-axis thickness of the second lens is d3, the on-axis distance from the image-side surface of the second lens to the object-side surface of the third lens is d4, the on-axis thickness of the third lens is d5, and the following relations are satisfied:

0.72≤f1/f≤0.90；

-0.85≤f2/f≤-0.65；

1.00≤f3/f≤1.20；

2.50≤R4/R3≤6.00；

1.50≤d1/d3≤2.50；

2.00≤d5/d4≤6.00。

2. the imaging optical lens according to claim 1, wherein a central radius of curvature of an object-side surface of the third lens is R5, a central radius of curvature of an image-side surface of the third lens is R6, and the following relationship is satisfied:

1.50≤R6/R5≤3.50。

3. the imaging optical lens of claim 1, wherein the object-side surface of the first lens element is convex at paraxial region and the image-side surface of the first lens element is convex at paraxial region;

the center curvature radius of the object side surface of the first lens is R1, the center curvature radius of the image side surface of the first lens is R2, the total optical length of the image pickup optical lens is TTL, and the following relational expression is satisfied:

-1.54≤(R1+R2)/(R1-R2)≤-0.07；

0.09≤d1/TTL≤0.31。

4. the imaging optical lens of claim 1, wherein the object-side surface of the second lens element is concave at the paraxial region and the image-side surface of the first lens element is convex at the paraxial region;

the total optical length of the shooting optical lens is TTL and meets the following relational expression:

-4.51≤(R3+R4)/(R3-R4)≤-0.93；

0.04≤d3/TTL≤0.18。

5. the imaging optical lens of claim 1, wherein the object-side surface of the third lens element is convex at paraxial region and the image-side surface of the first lens element is concave at paraxial region;

the central curvature radius of the object side surface of the third lens is R5, the central curvature radius of the image side surface of the third lens is R6, the total optical length of the photographic optical lens is TTL, and the following relational expression is satisfied:

-9.70≤(R5+R6)/(R5-R6)≤-1.20；

0.09≤d5/TTL≤0.50。

6. 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:

1.07≤f12/f≤5.58。

7. a camera optical lens according to claim 1, wherein the total optical length of the camera optical lens is TTL, the image height of the camera optical lens is IH, and the following relationship is satisfied:

TTL/IH≤1.64。

8. the imaging optical lens according to claim 1, wherein a field angle of the imaging optical lens is FOV, and satisfies the following relation:

FOV≥75.00°。

9. the imaging optical lens according to claim 1, wherein an aperture value of the imaging optical lens is FNO, and satisfies the following relationship:

FNO≤2.55。

Images