CN111025595B

Movatterモバイル変換

Info

Publication number: CN111025595B
Application number: CN201911396918.1A
Authority: CN
Inventors: 孙雯; 陈佳
Original assignee: Chengrui Optics Changzhou Co Ltd
Current assignee: Chengrui Optics Changzhou Co Ltd
Priority date: 2019-12-30
Filing date: 2019-12-30
Publication date: 2021-09-24
Anticipated expiration: 2039-12-30
Also published as: CN111025595A

Abstract

Translated fromChinese

本发明涉及光学镜头领域，公开了一种摄像光学镜头，该摄像光学镜头，自物侧至像侧依序包含：第一透镜，第二透镜，第三透镜，第四透镜，第五透镜；第一透镜至第五透镜中的至少一个含自由曲面，摄像光学镜头的焦距为f，第一透镜的焦距为f1，第二透镜的焦距为f2，第三透镜的焦距为f3，且满足下列关系式：0.80≤f1/f≤2.00；0.10≤f2/f3≤6.00。本发明提供的摄像光学镜头具有良好光学性能的同时，满足高分辨率、广角、良好成像质量的设计要求。

The invention relates to the field of optical lenses, and discloses an imaging optical lens. The imaging optical lens comprises: a first lens, a second lens, a third lens, a fourth lens, and a fifth lens in sequence from the object side to the image side; At least one of the first lens to the fifth lens contains a free-form surface, 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, and the focal length of the third lens is f3, and satisfy the following Relational formula: 0.80≤f1/f≤2.00; 0.10≤f2/f3≤6.00. The imaging optical lens provided by the invention has good optical performance and meets the design requirements of high resolution, wide angle and good imaging quality.

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

With the development of imaging lenses, people have higher and higher imaging requirements on the lenses, and night scene shooting and background blurring of the lenses also become important indexes for measuring the imaging standards of the lenses. At present, rotationally symmetrical aspheric surfaces are mostly adopted, and the aspheric surfaces only have sufficient freedom degree in a meridian plane and cannot well correct off-axis aberration. The free-form surface is a non-rotational symmetric surface type, so that aberration can be well balanced, imaging quality is improved, and the processing of the free-form surface is gradually mature. With the improvement of the requirements on lens imaging, the addition of the free-form surface is very important when the lens is designed, and the effect is more obvious particularly in the design of wide-angle and ultra-wide-angle lenses.

Disclosure of Invention

In view of the above problems, an object of the present invention is to provide an imaging optical lens having good optical performance, high resolution, wide angle, and good imaging quality.

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

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

at least one of the first lens element to the fifth lens element includes a free-form surface, the imaging optical lens element has a focal length f, the first lens element has a focal length f1, the second lens element has a focal length f2, the third lens element has a focal length f3, the third lens element has an object-side surface with a radius of curvature R5, and the third lens element has an image-side surface with a radius of curvature R6, and satisfies the following relationships: f1/f is more than or equal to 0.80 and less than or equal to 2.00; f2/f3 is more than or equal to 0.10 and less than or equal to 6.00; f3/f is not less than 6.47 and not more than-4.40; 3.71-5.37 of (R5+ R6)/(R5-R6).

Preferably, the fourth lens has an on-axis thickness of d7, the fifth lens has an on-axis thickness of d9, and the following relationship is satisfied: d7/d9 is more than or equal to 1.00 and less than or equal to 3.00.

Preferably, an on-axis distance from an image-side surface of the second lens to an object-side surface of the third lens is d4, an on-axis thickness of the third lens is d5, and the following relation is satisfied: d4/d5 is more than or equal to 0.10 and less than or equal to 1.20.

Preferably, the curvature radius of the object-side surface of the first lens element is R1, the curvature radius of the image-side surface of the first lens element is R2, the on-axis thickness of the first lens element is d1, and the total optical length of the imaging optical lens system is TTL and satisfies the following relationship: -3.81 (R1+ R2)/(R1-R2) is less than or equal to-0.75; d1/TTL is more than or equal to 0.05 and less than or equal to 0.19.

Preferably, the curvature radius of the object-side surface of the second lens element is R3, the curvature radius of the image-side surface of the second lens element is R4, the on-axis thickness of the second lens element is d3, and the total optical length of the imaging optical lens system is TTL and satisfies the following relationship: f2/f is not less than-1.43 and is not less than-56.60; (R3+ R4)/(R3-R4) is not more than 0.25 and not more than 32.39; d3/TTL is more than or equal to 0.03 and less than or equal to 0.09.

Preferably, 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 relation is satisfied: d5/TTL is more than or equal to 0.03 and less than or equal to 0.09.

Preferably, the focal length of the fourth lens element is f4, the radius of curvature of the object-side surface of the fourth lens element is R7, the radius of curvature of the image-side surface of the fourth lens element is R8, the on-axis thickness of the fourth lens element is d7, the total optical length of the image pickup optical lens is TTL, and the following relationships are satisfied: f4/f is more than or equal to 0.28 and less than or equal to 1.64; (R7+ R8)/(R7-R8) is not more than 0.64 and not more than 2.95; d7/TTL is more than or equal to 0.08 and less than or equal to 0.34.

Preferably, 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 relationships are satisfied: f5/f is not less than-2.28 and not more than-0.52; (R9+ R10)/(R9-R10) is not more than 1.08 and not more than 3.77; d9/TTL is more than or equal to 0.04 and less than or equal to 0.21.

Preferably, the total optical length of the image pickup optical lens is TTL, and satisfies the following relation: TTL is less than or equal to 4.45 mm.

Preferably, the F-number of the imaging optical lens is Fno, and the following relationship is satisfied: fno is less than or equal to 2.08.

The invention has the beneficial effects that: the pick-up optical lens has the characteristics of high resolution, wide angle and good imaging quality while having good optical performance, and is particularly suitable for a mobile phone pick-up lens assembly and a WEB pick-up lens which are composed of pick-up elements such as CCD (charge coupled device), CMOS (complementary metal oxide semiconductor) and the like for high pixels.

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 diagram of the imaging optics of FIG. 1 with the RMS spot diameter in the first quadrant;

fig. 3 is a schematic configuration diagram of an imaging optical lens according to a second embodiment of the present invention;

FIG. 4 is a diagram of the imaging optics of FIG. 3 with the RMS spot diameter in the first quadrant;

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

FIG. 6 is a plot of the RMS spot diameter for the imaging optics lens of FIG. 5 in the first quadrant;

fig. 7 is a schematic configuration diagram of an imaging optical lens according to a fourth embodiment of the present invention;

FIG. 8 is a plot of the RMS spot diameter for the imaging optics lens of FIG. 7 in the first quadrant;

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

fig. 10 is a view of the imaging optical lens of fig. 9 with the RMS spot diameter in the first quadrant;

fig. 11 is a schematic configuration diagram of an imaging optical lens according to a sixth embodiment of the present invention;

fig. 12 is a case where the RMS spot diameter of the imaging optical lens shown in fig. 11 is in the first quadrant.

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 pickupoptical lens 10. Fig. 1 shows an imagingoptical lens 10 according to a first embodiment of the present invention, and the imagingoptical lens 10 includes five lenses. Specifically, the imagingoptical 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.

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

The first lens L1 is made of plastic, the second lens L2 is made of plastic, the third lens L3 is made of plastic, the fourth lens L4 is made of plastic, and the fifth lens L5 is made of plastic.

In this embodiment, at least one of the first lens L1 to the fifth lens L5 is defined to include a free-form surface, which contributes to aberration correction such as astigmatism, field curvature, and distortion of the wide-angle optical system.

Defining the focal length f of the image pickupoptical lens 10 and the focal length f1 of the first lens L1, the following relations are satisfied: f1/f is more than or equal to 0.80 and less than or equal to 2.00, the ratio of the focal length of the first lens to the total focal length is specified, spherical aberration correction is facilitated within a condition range, and imaging quality is improved. Preferably, 0.84. ltoreq.f 1/f. ltoreq.1.95 is satisfied.

Defining the focal length of the second lens L2 as f2, and the focal length of the third lens L3 as f3, the following relations are satisfied: f2/f3 is more than or equal to 0.10 and less than or equal to 6.00, the ratio of the focal length of the second lens to the focal length of the third lens is specified, and the imaging quality is improved within the conditional expression range. Preferably, 0.23. ltoreq. f2/f 3. ltoreq.5.79 is satisfied.

Defining the on-axis thickness of the fourth lens L4 as d7 and the on-axis thickness of the fifth lens L5 as d9, the following relations are satisfied: 1.00-d 7/d 9-3.00, when d7/d9 meets the condition, the lens processing and assembling are facilitated. Preferably, 1.07. ltoreq. d7/d 9. ltoreq.2.78 is satisfied.

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: d4/d5 is more than or equal to 0.10 and less than or equal to 1.20, and when d4/d5 meets the condition, the total length of the compression system is favorably compressed, so that the system is ultra-thin. Preferably, 0.23. ltoreq. d4/d 5. ltoreq.1.15 is satisfied.

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: 3.81 ≦ (R1+ R2)/(R1-R2) ≦ -0.75, 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-2.38 ≦ (R1+ R2)/(R1-R2) ≦ -0.94.

The on-axis thickness of the first lens L1 is d1, the total optical length of the imagingoptical lens system 10 is TTL, and the following relationship is satisfied: d1/TTL is more than or equal to 0.05 and less than or equal to 0.19, and ultra-thinning is facilitated. Preferably, 0.08. ltoreq.d 1/TTL. ltoreq.0.15 is satisfied.

Defining the focal length of the second lens L2 as f2 and the focal length of the image pickupoptical lens 10 as f, the following relations are satisfied: 56.60 f2/f 1.43, 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. Preferably, it satisfies-35.37. ltoreq.f 2/f. ltoreq-1.79.

The curvature radius of the object side surface of the second lens L2 is R3, the curvature radius of the image side surface of the second lens L2 is R4, and the following relational expression is satisfied: the shape of the second lens element L2 is defined to be 0.25. ltoreq. (R3+ R4)/(R3-R4). ltoreq.32.39, and in the range, the problem of chromatic aberration on the axis is favorably corrected as the lens element is brought to an ultra-thin wide angle, and preferably, 0.39. ltoreq. (R3+ R4)/(R3-R4) is satisfied to be 0.39. ltoreq. 25.91.

The on-axis thickness of the second lens L2 is d3, the total optical length of the imagingoptical lens system 10 is TTL, and the following relationship is satisfied: d3/TTL is more than or equal to 0.03 and less than or equal to 0.09, and ultra-thinning is facilitated. Preferably, 0.04. ltoreq.d 3/TTL. ltoreq.0.08 is satisfied.

Defining the focal length of the third lens L3 as f3 and the focal length of the image pickupoptical lens 10 as f, the following relations are satisfied: 6.47 ≦ f3/f ≦ -4.40, allowing better imaging quality and lower sensitivity of the system through reasonable distribution of optical power.

The curvature radius of the object side surface of the third lens L3 is R5, the curvature radius of the image side surface of the third lens L3 is R6, and the following relational expression is satisfied: 3.71 ≦ (R5+ R6)/(R5-R6) ≦ 5.37, and defines the shape of the third lens, and within the range defined by the conditional expression, the deflection degree of the light passing through the lens can be alleviated, and the aberration can be effectively reduced.

The on-axis thickness of the third lens L3 is d5, the total optical length of the imagingoptical lens system 10 is TTL, and the following relationship is satisfied: d5/TTL is more than or equal to 0.03 and less than or equal to 0.09, and ultra-thinning is facilitated. Preferably, 0.04. ltoreq. d 5/TTL. ltoreq.0.08 is satisfied.

Defining the focal length of the fourth lens L4 as f4, and the focal length of the image pickupoptical lens 10 as f, the following relations are satisfied: f4/f is more than or equal to 0.28 and less than or equal to 1.64, the ratio of the focal length of the fourth lens to the focal length of the system is specified, and the performance of the optical system is improved in a conditional expression range. Preferably, 0.46. ltoreq. f 4/f. ltoreq.1.31 is satisfied.

The curvature radius of the object side surface of the fourth lens L4 is R7, the curvature radius of the image side surface of the fourth lens L4 is R8, and the following relational expression is satisfied: the shape of the fourth lens L4 is defined to be not less than 0.64 (R7+ R8)/(R7-R8) and not more than 2.95, and when the shape is within the range, the aberration of the off-axis picture angle is favorably corrected along with the development of the ultrathin wide angle. Preferably, 1.03 ≦ (R7+ R8)/(R7-R8) ≦ 2.36.

The on-axis thickness of the fourth lens L4 is d7, the total optical length of the imagingoptical lens system 10 is TTL, and the following relationship is satisfied: d7/TTL is more than or equal to 0.08 and less than or equal to 0.34, and ultra-thinning is facilitated. Preferably, 0.12. ltoreq.d 7/TTL. ltoreq.0.27 is satisfied.

Defining the focal length of the fifth lens L5 as f5, and the focal length of the image pickupoptical lens 10 as f, the following relations are satisfied: f5/f is less than or equal to-0.52, and the definition of the fifth lens L5 can effectively make the light angle of the camera lens smooth and reduce the tolerance sensitivity. Preferably, it satisfies-1.43. ltoreq. f 5/f. ltoreq-0.65.

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, and the following relationships are satisfied: the shape of the fifth lens L5 is defined to be not less than 1.08 (R9+ R10)/(R9-R10) and not more than 3.77, and when the shape is within the range, the aberration of the off-axis picture angle is favorably corrected along with the development of ultra-thin and wide-angle. Preferably, 1.73 ≦ (R9+ R10)/(R9-R10) ≦ 3.02.

The on-axis thickness of the fifth lens L5 is d9, the total optical length of the imagingoptical lens system 10 is TTL, and the following relationship is satisfied: d9/TTL is more than or equal to 0.04 and less than or equal to 0.21, and ultra-thinning is facilitated. Preferably, 0.07. ltoreq. d 9/TTL. ltoreq.0.17 is satisfied.

In the present embodiment, the F number of the aperture of the imagingoptical lens 10 is 2.08 or less, and the large aperture is good in imaging performance. Preferably, Fno is less than or equal to 2.04.

In this embodiment, the total optical length TTL of the image pickupoptical lens 10 is less than or equal to 4.45 millimeters, which is beneficial to achieving ultra-thinning. Preferably, the total optical length TTL is less than or equal to 4.24 millimeters.

When the above relationship is satisfied, the image pickupoptical lens 10 has good optical performance, and the free-form surface is adopted, so that the matching of the designed image surface area and the actual use area can be realized, and the image quality of the effective area is improved to the maximum extent; in accordance with the characteristics of theoptical lens 10, theoptical 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 pickupoptical 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 units of focal length, on-axis distance, radius of curvature, on-axis thickness are 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;

tables 1 and 2 show design data of the imagingoptical lens 10 according to the first embodiment of the present invention. The object-side surface and the image-side surface of the first lens L1 are free-form surfaces.

[ 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;

d: on-axis thickness of the lenses and 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 imagingoptical lens 10 according to the first embodiment of the present invention.

[ TABLE 2 ]

Where k is a conic coefficient, a4, a6, A8, a10, a12, a14, a16, a18, and a20 are aspheric coefficients, r is a perpendicular distance between a point on an aspheric curve and an 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).

z＝(cr²)/[1+{1-(k+1)(c²r²)}^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).

Table 3 shows free-form surface data in the imagingoptical lens 10 according to the first embodiment of the present invention.

[ TABLE 3 ]

Where k is a conic coefficient, Bi is an aspheric coefficient, r is a perpendicular distance between a point on the free-form surface and the optical axis, x is an x-direction component of r, y is a y-direction component of r, and z is an aspheric depth (a perpendicular distance between a point on the aspheric surface at a distance of r from the optical axis and a tangent plane tangent to a vertex on the aspheric optical axis).

For convenience, each free-form surface uses an Extended Polynomial surface type (Extended Polynomial) shown in the above formula (2). However, the present invention is not limited to the free-form surface polynomial form expressed by this formula (2).

Fig. 2 shows a case where the RMS spot diameter of the imagingoptical lens 10 of the first embodiment is in the first quadrant, and it can be seen from fig. 2 that the imagingoptical lens 10 of the first embodiment can achieve good image quality.

Table 19 shown later shows values corresponding to the parameters specified in the conditional expressions for the respective numerical values in examples 1, 2, 3, 4, 5, and 6.

As shown in table 19, the first embodiment satisfies each conditional expression.

In the present embodiment, the imaging optical lens has an entrance pupil diameter ENPD of 1.559mm, a full field image height (diagonal direction) IH of 5.470mm, an x-direction image height of 4.200mm, and a y-direction image height of 3.500mm, and has the best imaging effect in the rectangular range, a diagonal field angle FOV of 81.00 °, an x-direction field angle of 66.44 °, a y-direction field angle of 57.28 °, a wide angle, and a high profile, and has excellent optical characteristics with sufficient on-axis and off-axis chromatic aberration correction.

(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 4 and 5 show design data of the imagingoptical lens 20 according to the second embodiment of the present invention. The object-side surface and the image-side surface of the fifth lens L5 are free-form surfaces.

[ TABLE 4 ]

Table 5 shows aspherical surface data of each lens in the imagingoptical lens 20 according to the second embodiment of the present invention.

[ TABLE 5 ]

Table 6 shows free-form surface data in the imagingoptical lens 20 according to the second embodiment of the present invention.

[ TABLE 6 ]

Fig. 4 shows a case where the RMS spot diameter of the imagingoptical lens 20 of the second embodiment is in the first quadrant, and it can be seen from fig. 4 that the imagingoptical lens 20 of the second embodiment can achieve good image quality.

As shown in table 19, the second embodiment satisfies each conditional expression.

In the present embodiment, the imaging optical lens has an entrance pupil diameter ENPD of 1.580mm, a full field image height (diagonal direction) IH of 5.470mm, an x-direction image height of 4.200mm, and a y-direction image height of 3.500mm, and has the best imaging effect in this rectangular range, a diagonal field angle FOV of 78.18 °, an x-direction field angle of 64.27 °, a y-direction field angle of 56.58 °, a wide angle, and a high profile, and has excellent optical characteristics with sufficient correction of on-axis and off-axis chromatic aberration.

(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 7 and 8 show design data of the imagingoptical lens 30 according to the third embodiment of the present invention. The object-side surface and the image-side surface of the fourth lens L4 are free-form surfaces.

[ TABLE 7 ]

Table 8 shows aspherical surface data of each lens in the imagingoptical lens 30 according to the third embodiment of the present invention.

[ TABLE 8 ]

Table 9 shows free-form surface data in the imagingoptical lens 30 according to the third embodiment of the present invention.

[ TABLE 9 ]

Fig. 6 shows a case where the RMS spot diameter of the imagingoptical lens 30 of the third embodiment is in the first quadrant, and it can be seen from fig. 6 that the imagingoptical lens 30 of the third embodiment can achieve good image quality.

Table 19 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 ENPD of 1.539mm, a full field image height (diagonal direction) IH of 5.470mm, an x-direction image height of 4.200mm, and a y-direction image height of 3.500mm, and has the best imaging effect in the rectangular range, a diagonal field angle FOV of 80.70 °, an x-direction field angle of 66.68 °, a y-direction field angle of 57.52 °, a wide angle, and a slim shape, and has excellent optical characteristics with its on-axis and off-axis chromatic aberration sufficiently corrected.

(fourth embodiment)

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

Tables 10 and 11 show design data of the imagingoptical lens 40 according to the fourth embodiment of the present invention. The object-side surface and the image-side surface of the fifth lens L5 are free-form surfaces.

[ TABLE 10 ]

Table 11 shows aspherical surface data of each lens in the imagingoptical lens 40 according to the fourth embodiment of the present invention.

[ TABLE 11 ]

Table 12 shows free-form surface data in the imagingoptical lens 40 according to the fourth embodiment of the present invention.

[ TABLE 12 ]

Fig. 8 shows a case where the RMS spot diameter of the imagingoptical lens 40 of the fourth embodiment is in the first quadrant, and it can be seen from fig. 8 that the imagingoptical lens 40 of the fourth embodiment can achieve good image quality.

In the present embodiment, the imaging optical lens has an entrance pupil diameter ENPD of 1.189mm, a full field image height (diagonal direction) IH of 4.760mm, an x-direction image height of 3.810mm, and a y-direction image height of 2.860mm, and has the best imaging effect in this rectangular range, a diagonal field angle FOV of 87.75 °, an x-direction field angle of 79.14 °, a y-direction field angle of 61.00 °, a wide angle and a thin profile, and has excellent optical characteristics with sufficiently corrected on-axis and off-axis chromatic aberration.

(fifth embodiment)

The fifth 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 13 and 14 show design data of the imagingoptical lens 50 according to the fifth embodiment of the present invention.

[ TABLE 13 ]

Table 14 shows aspherical surface data of each lens in the imagingoptical lens 50 according to the fifth embodiment of the present invention.

[ TABLE 14 ]

Table 15 shows free-form surface data in the imagingoptical lens 50 according to the fifth embodiment of the present invention.

[ TABLE 15 ]

Fig. 10 shows a case where the RMS spot diameter of the imagingoptical lens 50 of the fifth embodiment is in the first quadrant, and it can be seen from fig. 10 that the imagingoptical lens 50 of the fifth embodiment can achieve good image quality.

In the present embodiment, the imaging optical lens has an entrance pupil diameter ENPD of 1.186mm, a full field image height (diagonal direction) IIH of 4.760mm, an x-direction image height of 3.810mm, and a y-direction image height of 2.860mm, and has the best imaging effect in this rectangular range, a diagonal field angle FOV of 91.77 °, an x-direction field angle of 77.89 °, a y-direction field angle of 61.03 °, a wide angle, and a high profile, and has excellent optical characteristics with on-axis and off-axis chromatic aberration sufficiently corrected.

(sixth embodiment)

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

Tables 16 and 17 show design data of the imagingoptical lens 60 according to the sixth embodiment of the present invention. The object-side surface and the image-side surface of the second lens L2 are free-form surfaces.

[ TABLE 16 ]

Table 17 shows aspherical surface data of each lens in the imagingoptical lens 60 according to the sixth embodiment of the present invention.

[ TABLE 17 ]

Table 18 shows free-form surface data in the imagingoptical lens 60 according to the sixth embodiment of the present invention.

[ TABLE 18 ]

Fig. 12 shows a case where the RMS spot diameter of the imagingoptical lens 60 of the sixth embodiment is in the first quadrant, and it can be seen from fig. 12 that the imagingoptical lens 60 of the sixth embodiment can achieve good image quality.

In the present embodiment, the imaging optical lens has an entrance pupil diameter ENPD of 1.19mm, a full field image height (diagonal direction) IH of 4.760mm, an x-direction image height of 3.810mm, and a y-direction image height of 2.860mm, and has the best imaging effect in this rectangular range, a diagonal field angle FOV of 91.73 °, an x-direction field angle of 77.66 °, a y-direction field angle of 60.86 °, a wide angle and a slim size, and has excellent optical characteristics with sufficiently corrected on-axis and off-axis chromatic aberration.

[ TABLE 19 ]

Parameter and condition formula	Example 1	Example 2	Example 3	Example 4	Example 5	Example 6
							f1/f	0.87	0.88	0.89	1.90	1.89	1.82
f2/f3	0.35	0.36	0.35	5.57	3.85	2.82
							f	3.117	3.159	3.077	2.405	2.400	2.407
f1	2.711	2.780	2.740	4.574	4.523	4.379
							f2	-6.677	-6.796	-6.986	-68.059	-40.695	-30.639
f3	-19.261	-18.884	-19.895	-12.229	-10.570	-10.881
							f4	3.398	3.094	3.016	1.369	1.370	1.370
f5	-3.544	-3.602	-3.245	-1.877	-1.944	-1.935
							Fno	2.00	2.00	2.00	2.02	2.02	2.02

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

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

Claims

1. An imaging optical lens system comprising five lens elements, in order from an object side to an image side: the lens comprises a first lens, a second lens, a third lens, a fourth lens and a fifth lens;

at least one of the first lens element to the fifth lens element includes a free-form surface, the imaging optical lens element has a focal length f, the first lens element has a focal length f1, the second lens element has a focal length f2, the third lens element has a focal length f3, the third lens element has an object-side surface with a radius of curvature R5, and the third lens element has an image-side surface with a radius of curvature R6, and satisfies the following relationships:

0.80≤f1/f≤2.00；

0.10≤f2/f3≤6.00；

-6.47≤f3/f≤-4.40；

3.71≤(R5+R6)/(R5-R6)≤5.37。

2. the imaging optical lens according to claim 1, wherein the fourth lens has an on-axis thickness of d7, the fifth lens has an on-axis thickness of d9, and the following relationship is satisfied:

1.00≤d7/d9≤3.00。

3. the imaging optical lens of claim 1, wherein an on-axis distance from an image-side surface of the second lens to an object-side surface of the third lens is d4, an on-axis thickness of the third lens is d5, and the following relationship is satisfied:

0.10≤d4/d5≤1.20。

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

-3.81≤(R1+R2)/(R1-R2)≤-0.75；

0.05≤d1/TTL≤0.19。

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

-56.60≤f2/f≤-1.43；

0.25≤(R3+R4)/(R3-R4)≤32.39；

0.03≤d3/TTL≤0.09。

6. a photographic optical lens according to claim 1, wherein the on-axis thickness of the third lens element is d5, the total optical length of the photographic optical lens is TTL, and the following relationship is satisfied:

0.03≤d5/TTL≤0.09。

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

0.28≤f4/f≤1.64；

0.64≤(R7+R8)/(R7-R8)≤2.95；

0.08≤d7/TTL≤0.34。

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

-2.28≤f5/f≤-0.52；

1.08≤(R9+R10)/(R9-R10)≤3.77；

0.04≤d9/TTL≤0.21。

9. a camera optical lens according to claim 1, wherein the total optical length of the camera optical lens is TTL and satisfies the following relation:

TTL≤4.45mm。

10. 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≤2.08。