CN111913284A

CN111913284A - Wide-angle lens with large image surface

Info

Publication number: CN111913284A
Application number: CN202010997841.XA
Authority: CN
Inventors: 韦晓鹏; 周小青
Original assignee: Sunny Optics Zhongshan Co Ltd
Current assignee: Sunny Optics Zhongshan Co Ltd
Priority date: 2020-09-21
Filing date: 2020-09-21
Publication date: 2020-11-10

Abstract

The invention relates to a large-image-plane wide-angle lens, which comprises a first lens (L1), a second lens (L2), a third lens (L3), a fourth lens (L4), a diaphragm, a fifth lens (L5), a sixth lens (L6), a seventh lens (L7), an eighth lens (L8), a ninth lens (L9) and a tenth lens (L10), wherein the first lens (L1), the second lens (L2), the fifth lens (L5) and the seventh lens (L7) are negative-power lenses; the third lens (L3), the fourth lens (L4), the sixth lens (L6), the eighth lens (L8), the ninth lens (L9), and the tenth lens (L10) are positive power lenses. The wide-angle lens with the large image plane has wide angle and low distortion performance, the half field angle is larger than 60 degrees, and the wide-angle lens has the function of automatic temperature compensation and does not have virtual focus within the temperature range of-40-85 ℃.

Description

Wide-angle lens with large image surface

Technical Field

The invention relates to the field of optical imaging, in particular to a large-image-surface wide-angle lens.

Background

The video conference lens belongs to high-end application scene optical equipment, and is required to have a large view field angle, imaging performance of tens of millions of pixels, a low-distortion imaging picture and strong environmental adaptability. The existing lens has the disadvantages of high development and design difficulty, high material cost and difficulty in simultaneously meeting the performance requirements of wide angle and low distortion.

Disclosure of Invention

The present invention is directed to solving the above problems and to providing a wide-angle lens with a large image plane.

In order to achieve the object of the present invention, the present invention provides a large-image-plane wide-angle lens, including a first lens, a second lens, a third lens, a fourth lens, a diaphragm, a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, and a tenth lens, which are arranged in order from an object side to an image side along an optical axis, wherein the first lens, the second lens, the fifth lens, and the seventh lens are negative-power lenses;

the third lens, the fourth lens, the sixth lens, the eighth lens, the ninth lens and the tenth lens are positive focal power lenses.

According to an aspect of the present invention, the first lens, the second lens, and the fifth lens are convex-concave lenses in an object-side to image-side direction;

the sixth lens, the eighth lens and the ninth lens are double-convex lenses;

the third lens is a concave-convex lens, and the seventh lens is a biconcave lens.

According to an aspect of the present invention, the fifth lens, the sixth lens and the seventh lens constitute a triple cemented lens, or the sixth lens and the seventh lens constitute a double cemented lens, or the sixth lens, the seventh lens and the eighth lens constitute a triple cemented lens.

According to one aspect of the invention, the refractive index of the fifth lens is Nd5, the Abbe number is Vd5, and the following conditions are satisfied: nd5 is more than or equal to 1.75 and less than or equal to 1.95, and Vd5 is more than or equal to 20.00 and less than or equal to 26.00.

According to one aspect of the invention, the refractive index of the sixth lens is Nd6, the Abbe number is Vd6, and the following conditions are satisfied: nd6 is more than or equal to 1.40 and less than or equal to 1.60, and Vd6 is more than or equal to 65.00 and less than or equal to 96.00.

According to one aspect of the invention, the seventh lens has a refractive index Nd7 and an abbe number Vd7, and satisfies the following conditions: nd7 is more than or equal to 1.60 and less than or equal to 1.80, and Vd7 is more than or equal to 25.00 and less than or equal to 35.00.

According to one aspect of the invention, the refractive index of the eighth lens is Nd8, the Abbe number is Vd8, and the following conditions are satisfied: nd8 is more than or equal to 1.40 and less than or equal to 1.60, and Vd8 is more than or equal to 65.00 and less than or equal to 96.00.

According to an aspect of the present invention, the second lens, the third lens, the ninth lens, and the tenth lens are aspherical lenses.

According to an aspect of the present invention, a half image height IH of the large-image-plane wide-angle lens and a field angle FOV of the large-image-plane wide-angle lens satisfy a relation: IH/tan (FOV/2) is more than or equal to 2.50 and less than or equal to 4.5.

According to one aspect of the invention, the effective focal length of the large-image-plane wide-angle lens is f, the axial distance from the optical surface of the tenth lens (10) close to the image plane is BFL, and the relation is satisfied: 0.35 is less than or equal to (1.25 x f-BFL)/BFL is less than or equal to 0.45.

According to the large-image-plane wide-angle lens, the lenses are arranged according to the above, and the large-angle incident light can be accommodated through reasonable arrangement and matching of the positive focal power lens and the negative focal power lens. And the incident light can sequentially pass through each optical deflection surface at a smaller angle, which is not only beneficial to correcting aberration and improving resolution performance, but also beneficial to reducing tolerance sensitivity.

According to the large-image-surface wide-angle lens, the first lens, the second lens and the fifth lens are convex-concave lenses along the direction from the object side to the image side; the sixth lens element, the eighth lens element and the ninth lens element are biconvex lenses; the third lens is a concave-convex lens, and the seventh lens is a biconcave lens. The lens at the specific position of the whole lens system can accommodate large-angle incident light rays in the bending direction and the presented shape, so that the wide-angle function is realized. The optical distortion can be effectively controlled, the low-distortion imaging effect can be realized, the incident height of light can be reduced, large-angle deflection of the light can be avoided, the aberration can be corrected, and the tolerance sensitivity can be reduced.

According to the large-image-plane wide-angle lens, the fifth lens, the sixth lens and the seventh lens form a triple cemented lens, or the sixth lens and the seventh lens form a double cemented lens, or the sixth lens, the seventh lens and the eighth lens form a triple cemented lens. So set up for between diaphragm and image plane, rationally arrange two cemented or three cemented lens, be favorable to rectifying the colour difference of wide-angle lens, guarantee imaging quality, improve the resolution performance, can reduce tolerance sensitivity simultaneously, improve the production yield.

The half image height IH of the large-image-surface wide-angle lens and the field angle FOV thereof satisfy the relational expression: IH/tan (FOV/2) is more than or equal to 2.50 and less than or equal to 4.5. The optical system can meet the superior performance of a large view field angle and a large image plane wide angle by meeting the relational expression, the distortion quantity of the optical system is effectively controlled, and the imaging effect of wide angle and low distortion is realized.

Drawings

Fig. 1 is a schematic view showing a configuration of a large-image-plane wide-angle lens according to embodiment 1 of the present invention;

fig. 2 schematically shows MTF charts of a large-image-plane wide-angle lens according to embodiment 1 of the present invention;

FIG. 3 is a diagram schematically showing a Through-Focus-MTF plot at-40 ℃ for a large-image-plane wide-angle lens according to embodiment 1 of the present invention;

FIG. 4 is a Through-Focus-MTF diagram schematically showing the high temperature of 85 ℃ for a large-image-plane wide-angle lens according to embodiment 1 of the present invention;

fig. 5 is a schematic view showing the configuration of a large-image-plane wide-angle lens according to embodiment 2 of the present invention;

fig. 6 schematically shows MTF charts of a large-image-plane wide-angle lens according to embodiment 2 of the present invention;

FIG. 7 is a diagram schematically showing a Through-Focus-MTF plot at-40 ℃ for a large-image-plane wide-angle lens according to embodiment 2 of the present invention;

FIG. 8 is a Through-Focus-MTF plot showing the high temperature of 85 ℃ for a large image plane wide-angle lens according to embodiment 2 of the present invention;

fig. 9 is a schematic view showing the configuration of a large-image-plane wide-angle lens according to embodiment 3 of the present invention;

fig. 10 schematically shows MTF charts of a large-image-plane wide-angle lens according to embodiment 3 of the present invention;

FIG. 11 is a diagram schematically showing a Through-Focus-MTF plot at-40 ℃ for a large-image-plane wide-angle lens according to embodiment 3 of the present invention;

FIG. 12 is a Through-Focus-MTF plot showing the high temperature of 85 ℃ for a large image plane wide-angle lens according to embodiment 3 of the present invention;

fig. 13 is a schematic view showing the configuration of a large-image-plane wide-angle lens according to embodiment 4 of the present invention;

fig. 14 schematically shows MTF charts of a large-image-plane wide-angle lens according to embodiment 4 of the present invention;

FIG. 15 is a diagram schematically showing a Through-Focus-MTF plot at-40 ℃ for a large-image-plane wide-angle lens according to embodiment 4 of the present invention;

FIG. 16 is a Through-Focus-MTF plot showing the high temperature of 85 ℃ for a large-image-plane wide-angle lens according to embodiment 4 of the present invention.

Detailed Description

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments will be briefly described below. It is obvious that the drawings in the following description are only some embodiments of the invention, and that for a person skilled in the art, other drawings can be derived from them without inventive effort.

The present invention is described in detail below with reference to the drawings and the specific embodiments, which are not repeated herein, but the embodiments of the present invention are not limited to the following embodiments.

Fig. 1 is a view schematically showing a configuration of a large-image-plane wide-angle lens according to an embodiment of the present invention. As shown in fig. 1, the large-image-plane wide-angle lens of the present invention includes: the zoom lens includes, in order from the object side to the image side along the optical axis, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a stop, a fifth lens L5, a sixth lens L6, a seventh lens L7, an eighth lens L8, a ninth lens L9, and a tenth lens L10. In the present invention, the first lens L1, the second lens L2, the fifth lens L5, and the seventh lens L7 are negative power lenses; the third lens L3, the fourth lens L4, the sixth lens L6, the eighth lens L8, the ninth lens L9, and the tenth lens L10 are positive power lenses.

In the present invention, the first lens L1, the second lens L2, and the fifth lens L5 are convex-concave lenses in the object-to-image direction; the sixth lens L6, the eighth lens L8, and the ninth lens L9 are double convex lenses; the third lens L3 is a meniscus lens, and the seventh lens L7 is a biconcave lens. The lens at the specific position of the whole lens system can accommodate large-angle incident light rays in the bending direction and the presented shape, so that the wide-angle function is realized. The optical distortion can be effectively controlled, the low-distortion imaging effect can be realized, the incident height of light can be reduced, large-angle deflection of the light can be avoided, the aberration can be corrected, and the tolerance sensitivity can be reduced.

In the present invention, the fifth lens L5, the sixth lens L6, and the seventh lens L7 constitute a triple cemented lens, or the sixth lens L6 and the seventh lens L7 constitute a double cemented lens, or the sixth lens L6, the seventh lens L7, and the eighth lens L8 constitute a triple cemented lens. So set up for between diaphragm and image plane, rationally arrange two cemented or three cemented lens, be favorable to rectifying the colour difference of wide-angle lens, guarantee imaging quality, improve the resolution performance, can reduce tolerance sensitivity simultaneously, improve the production yield.

In the present invention, the refractive index of the fifth lens L5 is Nd5, and the abbe number is Vd5, and satisfies: nd5 is more than or equal to 1.75 and less than or equal to 1.95, and Vd5 is more than or equal to 20.00 and less than or equal to 26.00. When the refractive index and the abbe number of the material used by the fifth lens L5 satisfy the above relationship, the aberration of the wide-angle lens with a large image plane can be corrected in a limited space, and the imaging quality can be ensured.

In the present invention, the refractive index of the sixth lens L6 is Nd6, and the abbe number is Vd6, and satisfies: nd6 is more than or equal to 1.40 and less than or equal to 1.60, and Vd6 is more than or equal to 65.00 and less than or equal to 96.00. When the refractive index and abbe number of the material used for the sixth lens L6 satisfy the above relationship, the chromatic aberration of the wide-angle lens can be corrected, and the resolution performance can be ensured. The stability of the effective focal length of the lens can be kept in different temperature environments, the automatic temperature compensation function is realized, and the imaging quality in different temperature environments is ensured.

In the present invention, the refractive index of the seventh lens L7 is Nd7, and the abbe number is Vd7, and satisfies: nd7 is more than or equal to 1.60 and less than or equal to 1.80, and Vd7 is more than or equal to 25.00 and less than or equal to 35.00. When the refractive index and abbe number of the material used for the seventh lens L7 satisfy the above relationship, the chromatic aberration of the wide-angle lens can be corrected, and the resolution performance can be ensured.

In the present invention, the refractive index of the eighth lens L8 is Nd8, and the abbe number is Vd8, and satisfies: nd8 is more than or equal to 1.40 and less than or equal to 1.60, and Vd8 is more than or equal to 65.00 and less than or equal to 96.00. When the refractive index and abbe number of the material used for the eighth lens L8 satisfy the above relationship, the chromatic aberration of the wide-angle lens can be corrected, and the resolution performance can be ensured. The stability of the effective focal length of the lens can be kept in different temperature environments, the automatic temperature compensation function is realized, and the imaging quality in different temperature environments is ensured.

In the invention, the second lens L2, the third lens L3, the ninth lens L9 and the tenth lens L10 are aspheric lenses, and the rest of the lenses are spherical lenses, so that plastic non-curved lenses are designed and used at specific positions, various optical aberrations of the large-image-surface wide-angle lens can be corrected to a great extent, the resolution performance is improved, and the high-definition imaging requirement of ten million-level pixels is met. Meanwhile, the lens can be matched and complemented with spherical lenses made of other glass materials, the effective focal length of the lens is kept stable in different temperature environments, the temperature automatic compensation function is realized, and the imaging quality in different temperature environments is ensured.

The effective focal length of the large-image-plane wide-angle lens is f, the axial distance from an optical surface of the tenth lens L10 close to the image plane is BFL, and the relationship is satisfied as follows: 0.35 is less than or equal to (1.25 x f-BFL)/BFL is less than or equal to 0.45. By the arrangement, on the premise of meeting the effective focal length of the system, the optical surface of the tenth lens L10 close to the image surface has enough space to the image plane, so that an optical filter element can be placed, the influence of a non-visible spectrum is effectively filtered, and high-definition imaging image quality is ensured.

Four sets of embodiments are given below to specifically describe the glass-plastic hybrid lens according to the present invention in accordance with the above-described arrangement of the present invention. Since the large image plane wide-angle lens according to the present invention has 10 lenses in total, each lens has two optical surfaces, and in addition to the stop S, the imaging plane IMA of the lens, and the plane of the flat filter IR between the imaging plane IMA and the lens, there are a maximum of 23 optical surfaces when a double cemented lens is present among the 10 lenses. For convenience of description, the respective face numbers are designated as S1 to S23.

Six sets of embodiment data are as in table 1 below:

conditional formula (II)	Example 1	Example 2	Example 3	Example 4
					2.50≤IH/tan(FOV/2)≤3.55	3.53	3.20	2.89	2.58
1.75≤Nd5≤1.95	1.92	1.85	1.81	1.78
					20.00≤Vd5≤26.00	20.88	23.78	25.46	25.72
1.40≤Nd6≤1.60	1.59	1.50	1.46	1.44
					65.00≤Vd6≤96.00	68.62	81.61	90.19	95.10
1.60≤Nd7≤1.80	1.76	1.74	1.70	1.67
					25.00≤Vd7≤35.00	26.61	27.76	30.05	33.05
1.40≤Nd8≤1.60	1.44	1.46	1.50	1.59
					65.00≤Vd8≤96.00	95.10	90.19	81.61	68.62
0.35≤(1.25*f-BFL)/BFL≤0.45	0.36	0.39	0.43	0.45

The first implementation mode comprises the following steps:

fig. 1 is a diagram schematically illustrating a configuration of a large-image-plane wide-angle lens according to a first embodiment of the present invention.

In the first embodiment, the effective focal length f of the large-image-plane wide-angle lens is 5.65mm, the aperture value FN0 is 2.25, and the half field angle FOV/2 is 66.0 °. Wherein the sixth lens L6 and the seventh lens L7 constitute a double cemented lens.

Table 2 below lists relevant parameters of each lens of the present embodiment, including surface type, radius of curvature, thickness, refractive index of material, abbe number:

number of noodles	Surface type	Radius of curvature	Thickness of	Refractive index	Abbe number
						S1	Spherical surface	22.15	1.20	1.92	20.9
S2	Spherical surface	11.18	5.24
						S3	Aspherical surface	13.00	2.50	1.54	55.7
S4	Aspherical surface	4.85	10.59
						S5	Aspherical surface	-8.59	3.50	1.53	56.1
S6	Aspherical surface	-9.68	0.10
						S7	Spherical surface	14.37	2.56	1.90	31.4
S8	Spherical surface	298.60	6.26
						S9(Stop)	Spherical surface	Infinity	0.61
S10	Spherical surface	15.79	2.77	1.92	20.9
						S11	Spherical surface	9.83	0.16
S12	Spherical surface	11.74	2.52	1.59	68.6
						S13	Spherical surface	-5.22	0.80	1.76	26.6
S14	Spherical surface	34.91	0.20
						S15	Spherical surface	25.00	2.99	1.44	95.1
S16	Spherical surface	-9.79	0.10
						S17	Aspherical surface	35.00	3.00	1.53	56.1
S18	Aspherical surface	-29.05	1.39
						S19	Aspherical surface	22.68	3.50	1.53	56.1
S20	Aspherical surface	21.92	2.09
						S21	Spherical surface	Infinity	0.80	1.52	64.2
S22	Spherical surface	Infinity	2.12
						S23 (image plane)	Spherical surface	Infinity	-

TABLE 2

In this embodiment, the aspheric data is shown in table 3 below, where K is the conic constant of the surface, and A, B, C, D, E are aspheric coefficients of fourth, sixth, eighth, tenth, twelfth, fourteenth and sixteenth orders, respectively:

number of noodles

K

A

B

C

D

E

S3

0.03

3.42E-5

-8.81E-6

8.00E-8

-5.79E-10

8.13E-13

S4

-0.69

2.73E-4

-2.93E-5

-5.84E-9

5.22E-9

-5.94E-11

S5

-0.70

2.09E-4

-3.85E-6

2.72E-8

-2.03E-10

-5.75E-14

S6

-0.94

4.18E-6

-2.23E-6

8.60E-9

-5.91E-11

5.34E-13

S17

4.74

-3.85E-4

3.92E-6

-3.92E-7

2.16E-8

-8.68E-11

S18

-20.00

-8.01E-4

5.78E-6

-2.75E-8

2.24E-9

3.42E-11

S19

3.78

-6.76E-4

-2.17E-5

4.17E-7

-3.72E-10

-3.83E-11

S20

-6.85

2.69E-4

-3.94E-5

7.67E-7

-8.17E-9

3.77E-11

TABLE 3

FIGS. 2 to 4 are graphs schematically showing the MTF performance of the large-image-plane wide-angle lens according to the first embodiment, a-40 ℃ Through-Focus-MTF performance graph, and a +85 ℃ Through-Focus-MTF performance graph, respectively. As can be seen from fig. 2 to 4, the lens of the present embodiment has both wide-angle and low-distortion performance, a half field angle greater than 60 °, and an automatic temperature compensation function, and does not produce virtual focus in a temperature range of-40 ℃ to 85 ℃.

The second embodiment:

fig. 5 is a view schematically showing the configuration of a large-image-plane wide-angle lens according to a second embodiment of the present invention.

In the second embodiment, the effective focal length f of the large-image-plane wide-angle lens is 5.64mm, the aperture value FN0 is 2.30, and the half field angle FOV/2 is 68 °. Wherein the fifth lens L5, the sixth lens L6, and the seventh lens L7 constitute a triple cemented lens.

Table 4 below lists relevant parameters of each lens of the present embodiment, including surface type, radius of curvature, thickness, refractive index of material, abbe number:

surface of	Surface type	Radius of curvature	Thickness of	Refractive index	Abbe number
						S1	Spherical surface	22.23	1.22	1.92	20.9
S2	Spherical surface	11.18	5.26
						S3	Aspherical surface	13.05	2.48	1.54	55.7
S4	Aspherical surface	4.85	10.57
						S5	Aspherical surface	-8.67	3.60	1.53	56.1
S6	Aspherical surface	-9.78	0.10
						S7	Spherical surface	13.68	2.59	1.90	31.4
S8	Spherical surface	140.55	6.25
						S9(Stop)	Spherical surface	Infinity	0.67
S10	Spherical surface	18.23	2.82	1.85	23.8
						S11	Spherical surface	11.51	2.55	1.50	81.6
S12	Spherical surface	-5.15	0.80	1.74	27.8
						S13	Spherical surface	33.06	0.26
S14	Spherical surface	28.33	3.05	1.46	90.2
						S15	Spherical surface	-9.69	0.12
S16	Aspherical surface	35.73	2.99	1.53	56.1
						S17	Aspherical surface	-30.57	1.22
S18	Aspherical surface	22.71	3.45	1.53	56.1
						S19	Aspherical surface	21.87	2.09
S20	Spherical surface	Infinity	0.80	1.52	64.2
						S21	Spherical surface	Infinity	2.11
S22 (image plane)	Spherical surface	Infinity	-

TABLE 4

In this embodiment, the aspheric data is shown in table 5 below, where K is the conic constant of the surface, and A, B, C, D, E are aspheric coefficients of fourth, sixth, eighth, tenth, twelfth, fourteenth and sixteenth orders, respectively:

number of noodles

K

A

B

C

D

E

S3

0.03

3.54E-5

-8.80E-6

8.00E-8

-5.79E-10

8.12E-13

S4

-0.69

2.73E-4

-2.93E-5

-6.37E-9

5.21E-9

-5.94E-11

S5

-0.70

2.08E-4

-3.86E-6

2.72E-8

-8.76E-11

4.65E-15

S6

-0.94

4.08E-6

-2.22E-6

8.75E-9

-5.95E-11

5.80E-13

S16

3.48

-3.90E-4

3.89E-6

-3.93E-7

2.16E-8

-8.52E-11

S17

-21.23

-8.00E-4

5.78E-6

-2.59E-8

2.28E-9

3.47E-11

S18

3.78

-6.77E-4

-2.17E-5

4.16E-7

-4.03E-10

-5.83E-11

S19

-7.35

2.65E-4

-3.94E-5

7.66E-7

-8.17E-9

3.76E-11

TABLE 5

FIGS. 6 to 8 are graphs schematically showing MTF performance, -40 ℃ Through-Focus-MTF performance, and +85 ℃ Through-Focus-MTF performance of the large-image-plane wide-angle lens according to the second embodiment. As can be seen from fig. 6 to 8, the lens of the present embodiment has both wide-angle and low-distortion performance, a half field angle greater than 60 °, and an automatic temperature compensation function, and does not produce virtual focus in a temperature range of-40 ℃ to 85 ℃.

The third embodiment is as follows:

fig. 9 is a view schematically showing the configuration of a large-image-plane wide-angle lens according to a third embodiment of the present invention.

In the third embodiment, the effective focal length f of the large-image-plane wide-angle lens is 5.66mm, the aperture value FN0 is 2.35, and the half field angle FOV/2 is 70 °. Wherein the sixth lens L6, the seventh lens L7, and the eighth lens L8 constitute a triple cemented lens.

Table 6 below lists relevant parameters of each lens of the present embodiment, including surface type, radius of curvature, thickness, refractive index of material, abbe number:

TABLE 6

In the present embodiment, the aspheric data is as shown in table 7 below, where K is a conic constant of the surface, and A, B, C, D, E are aspheric coefficients of fourth, sixth, eighth, tenth, twelfth, fourteenth, and sixteenth orders, respectively:

number of noodles

K

A

B

C

D

E

S3

0.03

3.44E-5

-8.82E-6

8.00E-8

-5.79E-10

8.11E-13

S4

-0.70

2.73E-4

-2.93E-5

-5.99E-9

5.21E-9

-5.96E-11

S5

-0.68

2.05E-4

-3.89E-6

2.74E-8

-6.04E-11

-7.98E-13

S6

-0.93

3.67E-6

-2.23E-6

9.17E-9

-5.99E-11

5.88E-13

S16

4.99

-3.74E-4

4.23E-6

-3.88E-7

2.17E-8

-2.05E-10

S17

-19.04

-8.12E-4

5.54E-6

-2.53E-8

2.23E-9

2.70E-11

S18

3.76

-6.76E-4

-2.17E-5

4.13E-7

-4.51E-10

-5.81E-11

S19

-9.63

2.54E-4

-3.95E-5

7.67E-7

-8.15E-9

3.82E-11

TABLE 7

FIGS. 10 to 12 are graphs schematically showing MTF performance, -40 ℃ Through-Focus-MTF performance, and +85 ℃ Through-Focus-MTF performance of the large-image-plane wide-angle lens according to the third embodiment, respectively. As can be seen from fig. 10 to 12, the lens of the present embodiment has both wide-angle and low-distortion performance, a half field angle greater than 60 °, and an automatic temperature compensation function, and does not produce a virtual focus in a temperature range of-40 ℃ to 85 ℃.

The fourth embodiment:

fig. 13 is a view schematically showing the configuration of a large-image-plane wide-angle lens according to a fourth embodiment of the present invention.

In the fourth embodiment, the effective focal length f of the large-image-plane wide-angle lens is 5.63mm, the aperture value FN0 is 2.40, and the half field angle FOV/2 is 72 °. Wherein the sixth lens L6 and the seventh lens L7 constitute a double cemented lens.

Table 8 below lists relevant parameters of each lens of the present embodiment, including surface type, radius of curvature, thickness, refractive index of material, abbe number:

TABLE 8

In this embodiment, the aspheric data is shown in table 9 below, where K is the conic constant of the surface, and A, B, C, D, E are aspheric coefficients of fourth, sixth, eighth, tenth, twelfth, fourteenth and sixteenth orders, respectively:

number of noodles

K

A

B

C

D

E

S3

0.03

3.42E-5

-8.80E-6

8.01E-8

-5.78E-10

8.16E-13

S4

-0.69

2.90E-4

-2.92E-5

-5.78E-9

5.22E-9

-5.87E-11

S5

-0.54

9.26E-5

-4.39E-6

9.93E-9

-4.70E-10

9.13E-12

S6

-1.06

2.39E-5

-2.43E-6

-7.31E-9

2.70E-10

8.76E-13

S17

3.79

-3.88E-4

3.80E-6

-3.93E-7

2.17E-8

-8.40E-11

S18

-23.22

-7.89E-4

6.03E-6

-2.44E-8

2.26E-9

3.42E-11

S19

3.56

-6.91E-4

-2.16E-5

4.21E-7

-2.86E-10

-3.72E-11

S20

-8.29

2.55E-4

-3.97E-5

7.65E-7

-8.16E-9

3.85E-11

TABLE 9

FIGS. 13 to 16 are graphs schematically showing MTF performance, -40 ℃ Through-Focus-MTF performance, and +85 ℃ Through-Focus-MTF performance of the large-image-plane wide-angle lens according to the fourth embodiment, respectively. As can be seen from fig. 13 to 16, the lens of the present embodiment has both wide-angle and low-distortion performance, a half field angle greater than 60 °, and an automatic temperature compensation function, and does not produce a virtual focus in a temperature range of-40 ℃ to 85 ℃.

The above description is only one embodiment of the present invention, and is not intended to limit the present invention, and it is apparent to those skilled in the art that various modifications and variations can be made in the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A large-image-plane wide-angle lens including a first lens (L1), a second lens (L2), a third lens (L3), a fourth lens (L4), a stop, a fifth lens (L5), a sixth lens (L6), a seventh lens (L7), an eighth lens (L8), a ninth lens (L9), and a tenth lens (L10) arranged in this order from an object side to an image side along an optical axis, characterized in that the first lens (L1), the second lens (L2), the fifth lens (L5), and the seventh lens (L7) are negative power lenses;

the third lens (L3), the fourth lens (L4), the sixth lens (L6), the eighth lens (L8), the ninth lens (L9), and the tenth lens (L10) are positive power lenses.

2. The large image plane wide-angle lens according to claim 1, wherein the first lens (L1), the second lens (L2), and the fifth lens (L5) are convex-concave lenses in an object-to-image direction;

the sixth lens (L6), eighth lens (L8), and ninth lens (L9) are double convex lenses;

the third lens (L3) is a meniscus lens, and the seventh lens (L7) is a biconcave lens.

3. The large image plane wide-angle lens of claim 1 or 2, wherein the fifth lens (L5), the sixth lens (L6), and the seventh lens (L7) constitute a triple cemented lens, or the sixth lens (L6) and the seventh lens (L7) constitute a double cemented lens, or the sixth lens (L6), the seventh lens (L7), and the eighth lens (L8) constitute a triple cemented lens.

4. The large-image-plane wide-angle lens according to claim 3, wherein the refractive index of the fifth lens (L5) is Nd5, and the Abbe number is Vd5, and the following conditions are satisfied: nd5 is more than or equal to 1.75 and less than or equal to 1.95, and Vd5 is more than or equal to 20.00 and less than or equal to 26.00.

5. The large-image-plane wide-angle lens according to claim 3, wherein the refractive index of the sixth lens (L6) is Nd6, and the Abbe number is Vd6, and the following conditions are satisfied: nd6 is more than or equal to 1.40 and less than or equal to 1.60, and Vd6 is more than or equal to 65.00 and less than or equal to 96.00.

6. The large-image-plane wide-angle lens according to claim 3, wherein the seventh lens (L7) has a refractive index Nd7 and an Abbe number Vd7, and satisfies the following conditions: nd7 is more than or equal to 1.60 and less than or equal to 1.80, and Vd7 is more than or equal to 25.00 and less than or equal to 35.00.

7. The large-image-plane wide-angle lens according to claim 3, wherein the refractive index of the eighth lens (L8) is Nd8, and the Abbe number is Vd8, and the following conditions are satisfied: nd8 is more than or equal to 1.40 and less than or equal to 1.60, and Vd8 is more than or equal to 65.00 and less than or equal to 96.00.

8. The large-image-plane wide-angle lens according to claim 1 or 2, wherein the second lens (L2), the third lens (L3), the ninth lens (L9), and the tenth lens (L10) are aspherical lenses.

9. The large image plane wide-angle lens of claim 1, wherein a half height IH of the large image plane wide-angle lens and a field angle FOV of the large image plane wide-angle lens satisfy the relationship: IH/tan (FOV/2) is more than or equal to 2.50 and less than or equal to 4.5.

10. The large image plane wide-angle lens of claim 1, wherein the effective focal length of the large image plane wide-angle lens is f, and the axial distance from the optical surface of the tenth lens (L10) close to the image plane is BFL, satisfying the relation: 0.35 is less than or equal to (1.25 x f-BFL)/BFL is less than or equal to 0.45.