CN110221410B

CN110221410B - Image pickup optical lens

Info

Publication number: CN110221410B
Application number: CN201910581782.5A
Authority: CN
Inventors: 王小锋; 陈佳
Original assignee: AAC Technologies Pte Ltd
Current assignee: AAC Technologies Pte Ltd
Priority date: 2019-06-30
Filing date: 2019-06-30
Publication date: 2021-07-30
Anticipated expiration: 2039-06-30
Also published as: CN110221410A

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 positive refractive power, a second lens element with negative refractive power, a third lens element with negative refractive power, a fourth lens element with positive refractive power, and a fifth lens element with negative refractive power; the focal length of the image pickup optical lens is f, the focal length of the first lens is f1, the on-axis thickness of the third lens is d5, the on-axis distance d6 from the image side surface of the third lens to the object side surface of the fourth lens is d6, the radius of curvature of the object side surface of the fourth lens is R7, and the radius of curvature of the image side surface of the fourth lens is R8, so that the following relational expressions are satisfied: f1/f is more than or equal to 0.40 and less than or equal to 0.60; d6/d5 is more than or equal to 7.00 and less than or equal to 15.00; 6.00 is less than or equal to (R7+ R8)/(R7-R8) is less than or equal to 30.00. The camera optical lens provided by the invention has good optical performance, and meets the design requirements of long focal length and ultra-thinness.

Description

Image pickup optical lens

[ technical field ] A method for producing a semiconductor device

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 of the invention ]

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) Sensor, and due to the advanced semiconductor manufacturing process technology, the pixel size of the photosensitive devices is reduced, and in addition, the current electronic products are developed with a good function, a light weight, a small size and a light weight, 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. However, with the development of technology and the increasing 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 for the imaging quality is continuously improved, the five-piece lens structure gradually appears in the lens design, although the common five-piece lens has good optical performance, the focal power, the lens interval and the lens shape setting still have certain irrationality, so that the design requirements of long focal length and ultra-thinness cannot be met while the lens structure has good optical performance.

[ summary of the 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 long focal length and an ultra-thin profile.

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 positive refractive power, a second lens element with negative refractive power, a third lens element with negative refractive power, a fourth lens element with positive refractive power, and a fifth lens element with negative refractive power;

the total system focal length of the image pickup optical lens is f, the focal length of the first lens is f1, the on-axis thickness of the third lens is d5, the on-axis distance d6 from the image side surface of the third lens to the object side surface of the fourth lens is d6, the curvature radius of the object side surface of the fourth lens is R7, and the curvature radius of the image side surface of the fourth lens is R8, so that the following relations are satisfied:

0.40≤f1/f≤0.60；

7.00≤d6/d5≤15.00；

6.00≤(R7+R8)/(R7-R8)≤30.00。

preferably, the focal length of the third lens is f3, and the following relation is satisfied:

-15.00≤f3/f≤-1.50。

preferably, the radius of curvature of the object-side surface of the second lens is R3, and the radius of curvature of the image-side surface of the second lens is R4, and the following relationships are satisfied:

-50.00≤R3/R4≤-15.00。

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 the following relationships are satisfied:

-2.93≤(R1+R2)/(R1-R2)≤-0.52；

0.06≤d1/TTL≤0.28。

preferably, the focal length of the second lens element is f2, 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 image pickup optical lens system is TTL, and the following relationships are satisfied:

-2.53≤f2/f≤-0.47；

0.44≤(R3+R4)/(R3-R4)≤1.44；

0.02≤d3/TTL≤0.16。

preferably, 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, and the total optical length of the imaging optical lens system is TTL, and the following relationships are satisfied:

-0.72≤(R5+R6)/(R5-R6)≤33.78；

0.01≤d5/TTL≤0.07。

preferably, the focal length of the fourth lens is f4, the on-axis thickness of the fourth lens is d7, and the total optical length of the imaging optical lens is TTL, and the following relationship is satisfied:

0.72≤f4/f≤4.70；

0.05≤d7/TTL≤0.17。

preferably, the focal length of the fifth lens element is f5, the radius of curvature of the object-side surface of the fifth lens element is R9, the radius of curvature of the image-side surface of the fifth lens element is R10, the on-axis thickness of the fifth lens element is d9, and the total optical length of the image pickup optical lens system is TTL, and the following relationships are satisfied:

-3.68≤f5/f≤-0.56；

-3.84≤(R9+R10)/(R9-R10)≤-0.67；

0.02≤d9/TTL≤0.09。

preferably, the combined focal length of the first lens and the second lens is f12, and the following relation is satisfied:

0.32≤f12/f≤1.30。

preferably, the F-number of the imaging optical lens is Fno, and the following relationship is satisfied:

Fno≤2.55。

the invention has the advantages that the pick-up optical lens has good optical performance, long focal length and ultra-thin characteristic, and is particularly suitable for mobile phone pick-up lens components and WEB pick-up lenses which are composed of pick-up elements such as CCD and CMOS for high pixel.

[ description of the 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;

fig. 2 is a schematic view of axial aberrations of the image-taking optical lens shown in 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 shown in FIG. 1;

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

fig. 6 is a schematic view of axial aberrations of the image pickup optical lens shown in 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 shown in FIG. 5;

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

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;

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

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 ] embodiments

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 five lenses. Specifically, the imaging optical lens 10, in order from an object side to an image side, includes: a diaphragm S1, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, and a fifth lens L5. An optical element such as an optical filter (filter) GF may be disposed between the fifth lens L5 and the image plane Si.

In this embodiment, the first lens element L1 has positive refractive power, the second lens element L2 has negative refractive power, the third lens element L3 has negative refractive power, the fourth lens element L4 has positive refractive power, and the fifth lens element L5 has negative refractive power.

In the present embodiment, the total system focal length of the imaging optical lens is f, and the focal length of the first lens is f1, and the following relational expression is satisfied: f1/f is more than or equal to 0.40 and less than or equal to 0.60; the ratio of the focal length of the first lens L1 to the total focal length of the system is specified, which can effectively balance the spherical aberration and the field curvature of the system.

Defining the on-axis thickness of the third lens L3 as d5, the on-axis distance d6 from the image-side surface of the third lens L3 to the object-side surface of the fourth lens L4 satisfies the following relationship: d6/d5 is more than or equal to 7.00 and less than or equal to 15.00. The ratio of the air space between the third lens L3 and the fourth lens L4 to the thickness of the third lens L3 is defined, and the total length of the optical system can be reduced within the conditional expression range, thereby achieving the effect of making the optical system thinner.

The curvature radius of the object side surface of the fourth lens is defined as R7, the curvature radius of the image side surface of the fourth lens is defined as R8, and the following relational expression is satisfied: the shape of the fourth lens L4 is defined to be 6.00. ltoreq. (R7+ R8)/(R7-R8) to 30.00. ltoreq. and in this range, it is advantageous to correct the aberration of the off-axis view angle.

The focal length of the third lens L3 is defined as f3, and the following relation is satisfied: f3/f is less than or equal to-15.00 and less than or equal to-1.50. The ratio of the focal length of the third lens L3 to the total focal length of the system is specified, and the system has better imaging quality and lower sensitivity through reasonable distribution of the focal length.

The curvature radius of the object side surface of the second lens L2 is defined as R3, and the curvature radius of the image side surface of the second lens L2 is defined as R4, and the following relations are satisfied: R3/R4 is more than or equal to-50.00 and less than or equal to-15.00. The shape of the second lens L2 is defined, and within this condition range, it is advantageous to correct the on-axis chromatic aberration.

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: -2.93 ≤ (R1+ R2)/(R1-R2) ≤ 0.52; the shape of the first lens L1 is appropriately controlled so that the first lens L1 can effectively correct the system spherical aberration.

The on-axis thickness of the first lens L1 is defined as d1, and the total optical length of the image pickup optical lens 10 is defined as TTL, and the following relations are satisfied: d1/TTL is more than or equal to 0.06 and less than or equal to 0.28, and ultra-thinning is facilitated.

Defining the focal length of the second lens L2 as f2, the following relation is satisfied: 2.53 f2/f 0.47, which is advantageous for correcting the aberration of the optical system by controlling the negative power of the second lens L2 in a reasonable range.

The curvature radius of the object side surface of the second lens is defined as R3, the curvature radius of the image side surface of the second lens is defined as R4, and the following relations are satisfied: the second lens L2 is defined in a shape of (R3+ R4)/(R3-R4) of 0.44 or less and 1.44 or less, and when the second lens L2 is within the range, the problem of chromatic aberration on the axis is favorably corrected as the lens is made to have a super-thin wide angle.

The on-axis thickness of the second lens L2 is d3, and the total optical length of the imaging optical lens system 10 is TTL, and the following relationships are satisfied: d3/TTL is more than or equal to 0.02 and less than or equal to 0.16, and ultra-thinning is facilitated.

The curvature radius of the object side surface of the third lens L3 is R5, and the curvature radius of the image side surface of the third lens L3 is R6, and the following relations are satisfied: the ratio of (R5+ R6)/(R5-R6) is not less than 0.72 and not more than 33.78, the shape of the third lens L3 can be effectively controlled, the molding of the third lens L3 is facilitated, and the generation of poor molding and stress caused by the overlarge surface curvature of the third lens L3 is avoided.

The on-axis thickness of the third lens L3 is defined as d5, and the total optical length of the image pickup optical lens 10 is defined as TTL, and the following relations are satisfied: d5/TTL is more than or equal to 0.01 and less than or equal to 0.07, and ultra-thinning is facilitated.

Defining the focal length of the fourth lens L4 as f4, the following relation is satisfied: f4/f is more than or equal to 0.72 and less than or equal to 4.70, the ratio of the focal length of the fourth lens to the focal length of the system is specified, and the system has better imaging quality and lower sensitivity through reasonable distribution of the focal power.

The on-axis thickness of the fourth lens element L4 is d7, and the total optical length of the imaging optical lens system 10 is TTL, and satisfies the following relationship: d7/TTL is more than or equal to 0.05 and less than or equal to 0.17, and ultra-thinning is facilitated.

Defining the focal length of the fifth lens L5 as f5, the following relation is satisfied: f5/f is less than or equal to-3.68 and less than or equal to-0.56. The definition of the fifth lens L5 can effectively make the light ray angle of the camera lens smooth, and reduce tolerance sensitivity.

The curvature radius of the object side surface of the fifth lens L5 is defined as R9, and the curvature radius of the image side surface of the fifth lens is defined as R10, and the following relations are satisfied: -3.84 ≦ (R9+ R10)/(R9-R10) ≦ -0.67. The shape of the fifth lens L5 is defined, and when the shape is within the range, it is advantageous to correct the problem such as the aberration of the off-axis view angle with the progress of ultra-thinning and wide-angle.

The on-axis thickness of the fifth lens L5 is defined as d9, and the total optical length of the image pickup optical lens 10 is defined as TTL, and the following relationships are satisfied: d9/TTL is more than or equal to 0.02 and less than or equal to 0.09, and ultra-thinning is facilitated.

In this embodiment, the total optical length TTL of the image pickup optical lens 10 is less than or equal to 7.24 mm, which is beneficial to achieving ultra-thinning.

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.

Further, the total system focal length of the image pickup optical lens 10 is f, the combined focal length of the first lens L1 and the second lens L2 is f12, and the following relationships are satisfied: f12/f is more than or equal to 0.32 and less than or equal to 1.30; therefore, the aberration and distortion of the image pickup optical lens 10 can be eliminated, the back focal length of the image pickup optical lens 10 can be suppressed, and the miniaturization of the image lens system can be maintained. The F-number of the imaging optical lens 10 satisfies the following relational expression: fno is less than or equal to 2.55, which is beneficial to realizing large aperture and ensures good imaging performance. That is, when the above relationship is satisfied, the imaging optical lens 10 can satisfy the design requirements of long focal length, large aperture and ultra-thinness while having good optical imaging performance; 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: radius of curvature of the object side of the optical filter GF;

r12: 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: the on-axis distance from the image-side surface of the fifth lens L5 to the object-side surface of the optical filter GF;

d 11: on-axis thickness of the optical filter GF;

d 12: 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;

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;

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.

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, and P5R1 and P5R2 represent the object-side surface and the image-side surface of the fifth lens L5, 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
			P1R1	0	0
P1R2	1	0.675
			P2R1	1	0.195
P2R2	0	0
			P3R1	1	0.415
P3R2	0	0
			P4R1	0	0
P4R2	0	0
			P5R1	0	0
P5R2	0	0

Fig. 2 shows a schematic diagram of axial aberrations of light having wavelengths of 436nm, 486nm, 546nm, 587nm, and 656nm after passing through the imaging optical lens 10 of the first embodiment, and fig. 3 shows a schematic diagram of chromatic aberration of magnification of light having wavelengths of 436nm, 486nm, 546nm, 587nm, and 656nm after passing through the imaging optical lens 10 of the first embodiment. Fig. 4 is a schematic view showing the field curvature and distortion of light having a wavelength of 546nm after passing through the imaging optical lens 10 according to the first embodiment, where the field curvature S in fig. 4 is the field curvature in the sagittal direction, and T is the field curvature in the tangential direction.

Table 17 shown later shows values corresponding to the parameters defined in the conditional expressions, for each of the numerical values in the first, second, third, and fourth embodiments.

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

In the present embodiment, the imaging optical lens 10 has an entrance pupil diameter of 3.045mm, a full field image height of 3.266mm, and a diagonal field angle of 46.14 °, so that it has excellent optical characteristics with a wide angle, an ultra-thin profile, and a sufficiently corrected on-axis and off-axis chromatic aberration.

(second embodiment)

The second embodiment is basically the same as the first embodiment, and the reference numerals are the same as those in the first embodiment, and the configuration of the image pickup optical lens 20 of the second embodiment is shown in fig. 5, and only the differences 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
				P1R1	1	1.455	0
P1R2	0	0	0
				P2R1	1	0.075	0
P2R2	0	0	0
				P3R1	1	0.285	0
P3R2	0	0	0
				P4R1	1	1.715	0
P4R2	2	1.885	2.105
				P5R1	1	1.755	0
P5R2	1	2.385	0

[ TABLE 8 ]

Fig. 6 shows a schematic diagram of axial aberrations of light with wavelengths of 436nm, 486nm, 546nm, 587nm, and 656nm after passing through the imaging optical lens 20 of the second embodiment, and fig. 7 shows a schematic diagram of chromatic aberration of magnification of light with wavelengths of 436nm, 486nm, 546nm, 587nm, and 656nm after passing through the imaging optical lens 20 of the second embodiment. Fig. 8 is a schematic view showing curvature of field and distortion of light having a wavelength of 546nm 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 20 has an entrance pupil diameter of 3.032mm, a full field image height of 3.266mm, and a diagonal field angle of 46.24 °, so that it has a wide angle of view, is made thinner, has a sufficient correction of on-axis and off-axis chromatic aberration, and has excellent optical characteristics.

(third embodiment)

The third embodiment is basically the same as the first embodiment, and the reference numerals are the same as those in the first embodiment, and the configuration of the imaging optical lens 30 of the third embodiment is shown in fig. 9, and only the 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	1.435	0
P1R2	2	0.505	1.145
				P2R1	1	0.145	0
P2R2	0	0	0
				P3R1	1	0.205	0
P3R2	0	0	0
				P4R1	1	1.655	0
P4R2	1	1.845	0
				P5R1	1	1.805	0
P5R2	1	2.305	0

[ TABLE 12 ]

	Number of stagnation points	Location of stagnation 1	Location of stagnation 2
				P1R1	0	0	0
P1R2	2	0.945	1.255
				P2R1	1	0.245	0
P2R2	0	0	0
				P3R1	1	0.345	0
P3R2	0	0	0
				P4R1	0	0	0
P4R2	0	0	0
				P5R1	0	0	0
P5R2	0	0	0

Fig. 10 shows a schematic diagram of axial aberrations of light having wavelengths of 436nm, 486nm, 546nm, 587nm, and 656nm passing through the imaging optical lens 30 according to the third embodiment, and fig. 11 shows a schematic diagram of chromatic aberration of magnification of light having wavelengths of 436nm, 486nm, 546nm, 587nm, and 656nm 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 546nm 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 2.93mm, a full field height of 3.266mm, and a diagonal field angle of 47.50 °, so that the imaging optical lens 30 has a wide angle, a slim profile, a long focal length, and 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 reference numerals are the same as those in the first embodiment, and the configuration of the imaging optical lens 40 of the fourth embodiment is shown in fig. 13, and only the 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	1	1.425	0
P1R2	1	0.495	0
				P2R1	1	0.885	0
P2R2	1	1.015	0
				P3R1	1	0.805	0
P3R2	0	0	0
				P4R1	2	1.725	1.905
P4R2	2	1.885	2.105
				P5R1	1	1.905	0
P5R2	2	0.015	2.435

[ TABLE 16 ]

Fig. 14 shows a schematic diagram of axial aberrations of light having wavelengths of 436nm, 486nm, 546nm, 587nm, and 656nm passing through the imaging optical lens 40 of the fourth embodiment, and fig. 15 shows a schematic diagram of chromatic aberration of magnification of light having wavelengths of 436nm, 486nm, 546nm, 587nm, and 656nm passing through the imaging optical lens 40 of the fourth embodiment. Fig. 16 is a schematic view showing curvature of field and distortion of light having a wavelength of 546nm after passing through the imaging optical lens 40 according to the fourth embodiment.

In the present embodiment, the imaging optical lens 40 has an entrance pupil diameter of 2.909mm, a full field height of 3.266mm, and a diagonal field angle of 47.92 °, so that it has a wide angle and a thin profile, and its on-axis and off-axis chromatic aberration is sufficiently corrected, and it has excellent optical characteristics.

[ TABLE 17 ]

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, in order from an object side to an image side, comprising: a first lens element with positive refractive power, a second lens element with negative refractive power, a third lens element with negative refractive power, a fourth lens element with positive refractive power, and a fifth lens element with negative refractive power;

the total system focal length of the image pickup optical lens is f, the focal length of the first lens is f1, the focal length of the third lens is f3, the on-axis thickness of the third lens is d5, the on-axis distance d6 from the image side surface of the third lens to the object side surface of the fourth lens is d6, the curvature radius of the object side surface of the fourth lens is R7, and the curvature radius of the image side surface of the fourth lens is R8, so that the following relational expression is satisfied:

0.40≤f1/f≤0.60；

7.00≤d6/d5≤15.00；

6.00≤(R7+R8)/(R7-R8)≤30.00；

-15.00≤f3/f≤-1.50。

2. the imaging optical lens of claim 1, wherein the radius of curvature of the object-side surface of the second lens is R3, and the radius of curvature of the image-side surface of the second lens is R4, and the following relationships are satisfied:

-50.00≤R3/R4≤-15.00。

3. the image-capturing optical lens of claim 1, wherein 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, and the total optical length of the image-capturing optical lens is TTL, and the following relationships are satisfied:

-2.93≤(R1+R2)/(R1-R2)≤-0.52；

0.06≤d1/TTL≤0.28。

4. the imaging optical lens of claim 1, wherein 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, and the total optical length of the imaging optical lens is TTL, and the following relationship is satisfied:

-2.53≤f2/f≤-0.47；

0.44≤(R3+R4)/(R3-R4)≤1.44；

0.02≤d3/TTL≤0.16。

5. the image-capturing optical lens unit according to claim 1, wherein 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, and the total optical length of the image-capturing optical lens unit is TTL, and the following relationships are satisfied:

-0.72≤(R5+R6)/(R5-R6)≤33.78；

0.01≤d5/TTL≤0.07。

6. the image-taking optical lens according to claim 1, wherein a focal length of the fourth lens is f4, an on-axis thickness of the fourth lens is d7, and an optical total length of the image-taking optical lens is TTL, and the following relationship is satisfied:

0.72≤f4/f≤4.70；

0.05≤d7/TTL≤0.17。

7. the image-taking optical lens according to claim 1, wherein the focal length of the fifth lens element is f5, the radius of curvature of the object-side surface of the fifth lens element is R9, and the radius of curvature of the image-side surface of the fifth lens element is R10, the on-axis thickness of the fifth lens element is d9, and the total optical length of the image-taking optical lens is TTL, and the following relationship is satisfied:

-3.68≤f5/f≤-0.56；

-3.84≤(R9+R10)/(R9-R10)≤-0.67；

0.02≤d9/TTL≤0.09。

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:

0.32≤f12/f≤1.30。

9. an image-capturing optical lens according to claim 1, characterized in that the F-number of the aperture of the image-capturing optical lens is Fno and satisfies the following relation:

Fno≤2.55。