阅读说明：本技术 广角镜头及成像设备 (Wide-angle lens and imaging apparatus ) 是由 魏文哲 刘绪明 曾吉勇 于 2019-08-20 设计创作，主要内容包括：本发明提供了一种广角镜头及成像设备,第一群组从物侧到成像面依次包括具有负光焦度的第一透镜、具有负光焦度的第二透镜以及具有光焦度的第三透镜,第一透镜的物侧表面为凸面像侧表面为凹面,第二透镜的像侧表面为凹面；第二群组依次包括具有正光焦度的第四透镜和具有正光焦度的第五透镜,第四透镜和第五透镜的像侧表面均为凸面；第三群组依次包括第六透镜、第七透镜、以及具有正光焦度的第八透镜,第八透镜的物侧表面和像侧表面均为凸面,第六透镜和所述第七透镜组成粘合体；光阑设置于所述第一群组和所述第二群组之间；滤光片设置于所述第三群组与成像面之间。本发明提供的广角镜头具有小畸变、高像素、大视场角、低公差敏感度的优点。(The invention provides a wide-angle lens and imaging equipment.A first group sequentially comprises a first lens with negative focal power, a second lens with negative focal power and a third lens with the negative focal power from an object side to an imaging surface, wherein the surface of the object side of the first lens is a convex surface, and the surface of the image side of the second lens is a concave surface; the second group sequentially comprises a fourth lens with positive focal power and a fifth lens with positive focal power, and the image side surfaces of the fourth lens and the fifth lens are convex surfaces; the third group sequentially comprises a sixth lens, a seventh lens and an eighth lens with positive focal power, the object side surface and the image side surface of the eighth lens are convex surfaces, and the sixth lens and the seventh lens form a bonding body; a diaphragm disposed between the first group and the second group; the optical filter is arranged between the third group and the imaging surface. The wide-angle lens provided by the invention has the advantages of small distortion, high pixel, large field angle and low tolerance sensitivity.)

1. A wide-angle lens, comprising, in order from an object side to an imaging plane:

a first group having a negative power, the first group including, in order from an object side to an imaging surface, a first lens having a negative power, a second lens having a negative power, and a third lens having a positive power or a negative power; the surface of the object side of the first lens is a convex surface, the surface of the image side of the first lens is a concave surface, and the surface of the image side of the second lens is a concave surface;

a second group having positive optical power, the second group including, in order from an object side to an imaging surface, a fourth lens having positive optical power and a fifth lens having positive optical power, an image side surface of the fourth lens and an image side surface of the fifth lens both being convex surfaces;

a third group having a positive optical power, the third group including, in order from an object side to an image plane, a sixth lens, a seventh lens, and an eighth lens having a positive optical power, both an object side surface and an image side surface of the eighth lens being convex, the sixth lens and the seventh lens constituting a bonded body;

a diaphragm disposed between the first group and the second group; and

the optical filter is arranged between the third group and the imaging surface;

wherein the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, and the eighth lens are all glass lenses.

2. The wide-angle lens of claim 1, wherein the wide-angle lens satisfies the following conditional expression:

-3＜(r₈+r₁₀)/f_Q2＜0；

wherein r is₈Represents a radius of curvature, r, of the image-side surface of the fourth lens element₁₀Represents a radius of curvature, f, of an image-side surface of the fifth lens element_Q2Representing a focal length of the second group.

3. The wide-angle lens of claim 1, wherein the wide-angle lens satisfies the following conditional expression:

0＜IH/θ≤0.05；

where θ denotes a half field angle of the wide-angle lens, and IH denotes an image height of the wide-angle lens at the half field angle θ.

4. The wide-angle lens of claim 1, wherein the wide-angle lens satisfies the following conditional expression:

wherein the content of the first and second substances,represents an optical power of an image side surface of the fifth lens,represents an optical power of an object side surface of the sixth lens,represents the optical power of the fifth lens,represents the power of the sixth lens.

5. The wide-angle lens of claim 1, wherein the wide-angle lens satisfies the following conditional expression:

0＜(f_L1+f_L2)/f_Q1＜10；

wherein f is_L1Denotes the focal length of the first lens, f_L2Denotes the focal length of the second lens, f_Q1Representing a focal length of the first group.

6. The wide-angle lens of claim 1, wherein the wide-angle lens satisfies the following conditional expression:

0＜(f₈/f_L4+f₁₀/f_L5)/f_Q2＜1；

wherein f is₈Denotes a focal length of an image side surface of the fourth lens, f₁₀Denotes a focal length f of an image side surface of the fifth lens_L4Denotes the focal length of the fourth lens, f_L5Denotes a focal length of the fifth lens, f_Q2Representing a focal length of the second group.

7. The wide-angle lens of claim 1, wherein the wide-angle lens satisfies the following conditional expression:

0＜ENPP/TTL＜0.2；

ENPP represents the entrance pupil position of the wide-angle lens, and TTL represents the total optical length of the wide-angle lens.

8. The wide-angle lens of claim 1, wherein an object-side surface and an image-side surface of the sixth lens element are convex, and an object-side surface and an image-side surface of the seventh lens element are concave.

9. The wide-angle lens of claim 1, wherein an object-side surface and an image-side surface of the sixth lens element are both concave, and wherein an object-side surface of the seventh lens element is convex.

10. The wide-angle lens of claim 1, wherein an object-side surface of the third lens element is concave, an image-side surface of the third lens element is convex, and an object-side surface of the second lens element is concave.

11. The wide-angle lens of claim 1, wherein an object-side surface of the third lens element is convex, an image-side surface of the third lens element is concave, and an object-side surface of the second lens element is convex.

12. The wide-angle lens of claim 1, wherein the second lens and the eighth lens are both glass aspheric lenses.

13. An imaging apparatus comprising the wide-angle lens according to any one of claims 1 to 12, and an imaging element for converting an optical image formed by the wide-angle lens into an electrical signal.

Technical Field

The invention relates to the technical field of lens imaging, in particular to a wide-angle lens and imaging equipment.

Background

With the development of the imaging technology of the optical lens, the wide-angle lens has been developed rapidly, but the current wide-angle imaging lens generally has large f-theta distortion, and because the incident angle of light is large, the edge aberration is difficult to correct, the MTF of the edge field is sensitive to tolerance, and the assembly yield is low. Based on this, design a section and have little distortion, high pixel, big wide angle's optical imaging system, through the control to the lens structure, effectively improve the equipment yield simultaneously.

Disclosure of Invention

The invention aims to provide a wide-angle lens and an imaging device, which have the advantages of small distortion, high pixel, large field angle and low tolerance sensitivity.

The embodiment of the invention achieves the aim through the following technical scheme.

In a first aspect, the present invention provides a wide-angle lens, comprising, in order from an object side to an image plane: the optical filter comprises a first group with negative focal power, a diaphragm, a second group with positive focal power, a third group with positive focal power and an optical filter. The first group sequentially comprises a first lens with negative focal power, a second lens with negative focal power and a third lens with positive focal power or negative focal power, wherein the object side surface of the first lens is a convex surface, the image side surface of the first lens is a concave surface, and the image side surface of the second lens is a concave surface; the second group comprises a fourth lens with positive focal power and a fifth lens with positive focal power in sequence from the object side to the imaging surface, and the image side surface of the fourth lens and the image side surface of the fifth lens are convex surfaces; the third group comprises a sixth lens, a seventh lens and an eighth lens with positive focal power in sequence from the object side to the imaging surface, the object side surface and the image side surface of the eighth lens are convex surfaces, and the sixth lens and the seventh lens form a bonded body; the diaphragm is arranged between the first group and the second group; the optical filter is arranged between the third group and the imaging surface; the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens are all glass lenses.

In a second aspect, the present invention also provides an imaging apparatus including the wide-angle lens provided in the first aspect, and an imaging element for converting an optical image formed by the wide-angle lens into an electrical signal.

Compared with the prior art, the wide-angle lens and the imaging device provided by the invention have the characteristics of small distortion, high pixel, large field angle and low tolerance sensitivity, wherein the second lens of the first group is mainly used for collecting light and controlling distortion, the second group is used for converging light, two lenses are used for sharing focal power, the condition that tolerance sensitivity is large due to the fact that the focal power of a single lens is too large is avoided, the assembly yield is obviously improved, and a bonding body consisting of the sixth lens and the seventh lens in the third group is used for eliminating chromatic aberration.

Drawings

Fig. 1 is a schematic structural diagram of a wide-angle lens according to a first embodiment of the present invention;

FIG. 2 is a field curvature diagram of a wide-angle lens according to a first embodiment of the present invention;

FIG. 3 is a diagram showing distortion of a wide-angle lens according to a first embodiment of the present invention;

FIG. 4 is a diagram of axial chromatic aberration of a wide-angle lens according to a first embodiment of the present invention;

FIG. 5 is a vertical axis chromatic aberration diagram of the wide-angle lens according to the first embodiment of the present invention;

FIG. 6 is a schematic structural diagram of a wide-angle lens according to a second embodiment of the present invention;

FIG. 7 is a field curvature diagram of a wide-angle lens according to a second embodiment of the present invention;

FIG. 8 is a diagram showing distortion of a wide-angle lens in a second embodiment of the present invention;

FIG. 9 is a diagram showing axial chromatic aberration of a wide-angle lens according to a second embodiment of the present invention;

FIG. 10 is a vertical axis chromatic aberration diagram of a wide-angle lens according to a second embodiment of the present invention;

FIG. 11 is a schematic structural diagram of a wide-angle lens according to a third embodiment of the present invention;

FIG. 12 is a field curvature diagram of a wide-angle lens according to a third embodiment of the present invention;

FIG. 13 is a diagram showing distortion of a wide-angle lens in a third embodiment of the present invention;

FIG. 14 is a diagram showing axial chromatic aberration of a wide-angle lens in a third embodiment of the present invention;

FIG. 15 is a vertical axis chromatic aberration diagram of a wide-angle lens according to a third embodiment of the present invention;

fig. 16 is a schematic structural diagram of a wide-angle lens in a fourth embodiment of the present invention;

FIG. 17 is a field curvature diagram of a wide-angle lens according to a fourth embodiment of the present invention;

FIG. 18 is a diagram showing distortion of a wide-angle lens in a fourth embodiment of the present invention;

FIG. 19 is a diagram showing axial chromatic aberration of a wide-angle lens in a fourth embodiment of the present invention;

fig. 20 is a vertical axis chromatic aberration diagram of the wide-angle lens in the fourth embodiment of the present invention.

Fig. 21 is a schematic structural view of an image forming apparatus in a fifth embodiment of the present invention.

Description of the reference numerals

The following detailed description will further illustrate the invention in conjunction with the above-described figures.

Detailed Description

To facilitate an understanding of the invention, the invention will now be described more fully with reference to the accompanying drawings. Several embodiments of the invention are presented in the drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

The invention provides a wide-angle lens, which sequentially comprises the following components from an object side to an imaging surface: the optical filter comprises a first group with negative focal power, a diaphragm, a second group with positive focal power, a third group with positive focal power and an optical filter. The first group sequentially comprises a first lens with negative focal power, a second lens with negative focal power and a third lens with positive focal power or negative focal power, wherein the object side surface of the first lens is a convex surface, the image side surface of the first lens is a concave surface, and the image side surface of the second lens is a concave surface; the second group comprises a fourth lens and a fifth lens which have positive focal power from the object side to the imaging surface in sequence, and the image side surface of the fourth lens and the image side surface of the fifth lens are convex surfaces; the third group comprises a sixth lens, a seventh lens and an eighth lens with positive focal power in sequence from the object side to the imaging surface, the object side surface of the eighth lens and the image side surface of the eighth lens are convex surfaces, and the sixth lens and the seventh lens form a bonding body; the diaphragm is arranged between the first group and the second group; the optical filter is arranged between the third group and the imaging surface; first lens, second lens, third lens, fourth lens, fifth lens, sixth lens, seventh lens and eighth lens are glass lens, adopt eight glass material lenses, make the camera lens have better thermal stability and mechanical strength to and better imaging.

In some embodiments, the present invention provides a wide-angle lens satisfying the following conditional expression:

-3＜(r₈+r₁₀)/f_Q2＜0； (1)

wherein r is₈Denotes a radius of curvature, r, of the image-side surface of the fourth lens element₁₀Denotes a radius of curvature, f, of the image-side surface of the fifth lens element_Q2Representing the focal length of the second group.

The conditional expression (1) is satisfied, so that the focal power of the fourth lens and the focal power of the fifth lens in the second group can be effectively shared, the condition that tolerance sensitivity is high due to overlarge focal power of a single lens is avoided, and the assembly yield is obviously improved.

In some embodiments, the present invention provides a wide-angle lens satisfying the following conditional expression:

0＜IH/θ≤0.05； (2)

where θ denotes a half angle of view of the wide-angle lens, and IH denotes an image height of the wide-angle lens at the half angle of view θ.

The magnification of the marginal field of view can be improved by controlling the f-theta distortion when the conditional expression (2) is satisfied, so that the marginal field of view has more pixels, the resolution capability of the optical lens margin is improved, and the marginal field of view has enough resolution after the shot picture is flattened and unfolded.

In some embodiments, the present invention provides a wide-angle lens satisfying the following conditional expression:

wherein the content of the first and second substances,denotes an optical power of the image side surface of the fifth lens,denotes the power of the object side surface of the sixth lens,the power of the fifth lens is shown,the power of the sixth lens is shown.

The beam-converging capability of the light of the fifth lens can be ensured, the light is ensured to be nearly parallel to the optical axis after passing through the fifth lens, and the subsequent correction of chromatic aberration, spherical aberration and other aberrations is facilitated; meanwhile, the incident angle of the light on the object side surface of the sixth lens element can be effectively reduced, and the generation of large aberration on the object side surface of the sixth lens element is avoided.

In some embodiments, the present invention provides a wide-angle lens satisfying the following conditional expression:

0＜(f_L1+f_L2)/f_Q1＜10； (4)

wherein f is_L1Denotes the focal length of the first lens, f_L2Denotes the focal length of the second lens, f_Q1Representing the focal length of the first group.

The optical lens meets the conditional expression (4), can effectively increase the field angle, ensures that the field angle of the wide-angle lens reaches more than 160 degrees, effectively reduces the included angle between light rays and an optical axis, is favorable for reducing edge aberration, and reduces the burden of subsequent lens correction aberration.

In some embodiments, the present invention provides a wide-angle lens satisfying the following conditional expression:

0＜(f₈/f_L4+f₁₀/f_L5)/f_Q2＜1； (5)

wherein f is₈Denotes a focal length of the image-side surface of the fourth lens element, f₁₀Denotes a focal length of the image side surface of the fifth lens element, f_L4Denotes the focal length of the fourth lens, f_L5Denotes the focal length of the fifth lens, f_Q2Representing the focal length of the second group.

And the condition formula (5) is satisfied, so that the relative aperture of the lens is increased, and the light transmission amount of the lens is improved.

In some embodiments, the present invention provides a wide-angle lens satisfying the following conditional expression:

0＜ENPP/TTL＜0.2； (6)

where ENPP denotes an entrance pupil position of the wide-angle lens, and TTL denotes an optical total length of the wide-angle lens.

The condition (6) is satisfied, so that the entrance pupil position of the lens is closer to the object side, and the relative illumination of the lens is favorably improved.

In some embodiments, the object-side surface and the image-side surface of the sixth lens element are both convex, and the object-side surface and the image-side surface of the seventh lens element are both concave, so that the sixth lens element and the seventh lens element form a cemented body, and by adopting the surface-type combination, chromatic aberration can be effectively eliminated, and spherical aberration can be reduced.

In some embodiments, the object-side surface and the image-side surface of the sixth lens element are concave, and the object-side surface of the seventh lens element is convex.

In some embodiments, an object-side surface of the third lens element is concave, an image-side surface of the third lens element is convex, and an object-side surface of the second lens element is concave.

In some embodiments, an object-side surface of the third lens element is convex, an image-side surface of the third lens element is concave, and an object-side surface of the second lens element is convex.

In some embodiments, the second lens and the eighth lens are both glass aspheric lenses.

Due to the adoption of the mode of combining the glass spherical lens and the glass non-spherical lens, the resolving power of the whole group of lenses is improved, the distortion and the emergent angle of the principal ray are reduced, and the good imaging effect of the lenses is ensured while the large field angle is achieved. The eighth lens is an aspheric lens which can effectively correct the effects of field curvature, spherical aberration and the like and is used for controlling the emergent angle of the main ray, and the second lens is a glass aspheric lens which is mainly used for collecting the light and controlling the distortion.

The present invention also provides an imaging apparatus, the wide-angle lens in any of the above embodiments, and an imaging element for converting an optical image formed by the wide-angle lens into an electrical signal.

The aspheric surface shape of the wide-angle lens in the embodiments of the present invention satisfies the following equation:

wherein z represents the distance in the optical axis direction from the curved surface vertex, c represents the curvature of the curved surface vertex, K represents the conic coefficient, h represents the distance from the optical axis to the curved surface, and B, C, D, E and F represent the fourth, sixth, eighth, tenth and twelfth order curved surface coefficients, respectively.

In the following embodiments, the thickness, the curvature radius, and the material selection part of each lens in the wide-angle lens provided by the present invention are different, and specific differences can be referred to the parameter tables of the embodiments.

First embodiment

Referring to fig. 1, a wide-angle lens 100 according to a first embodiment of the present invention includes, in order from an object side to an image plane S18: a first group Q1, a diaphragm ST, a second group Q2, a third group Q3, and a filter G1.

The first group Q1 has negative power, the first group Q1 includes two first lenses L1 having negative power, a second lens L2 having negative power, and a third lens L3 having positive power, in this order, wherein an object-side surface S1 of the first lens L1 is convex, an image-side surface S2 of the first lens L1 is concave, an object-side surface S3 of the second lens L2 is concave, an image-side surface S4 of the second lens L2 is convex, an object-side surface S5 of the third lens L3 is concave, and an image-side surface S6 of the third lens L3 is convex.

The second group Q2 has positive optical power, and the second group Q2 includes, in order, two fourth lenses L4 having positive optical power and a fifth lens L5 having positive optical power, in which an object-side surface S7 of the fourth lens L4 is a concave surface, an image-side surface S8 of the fourth lens L4 is a convex surface, and both the object-side surface S9 of the fifth lens L5 and the image-side surface S10 of the fifth lens L5 are convex surfaces.

The third group Q3 has positive optical power, the third group Q3 includes a sixth lens L6, a seventh lens L7 and an eighth lens L8, wherein the sixth lens L6 has negative optical power, the seventh lens L7 and the eighth lens L8 each have positive optical power, and the sixth lens L6 and the seventh lens L7 form an adhesive body, specifically, the image-side surface S12-1 of the sixth lens L6 and the object-side surface S12-2 of the seventh lens L7 are bonded integrally, that is, the image-side surface S12-1 of the sixth lens L6 and the object-side surface S12-2 of the seventh lens L7 are bonded seamlessly, and the bonding surface is S12. The object-side surface S11 of the sixth lens L6 and the image-side surface S12 of the sixth lens L6 are both concave, the object-side surface S12 of the seventh lens L7 is convex, the image-side surface S13 of the seventh lens L7 is concave, and the object-side surface S14 of the eighth lens L8 and the image-side surface S15 of the eighth lens L8 are both convex.

The stop ST is disposed between the first group Q1 and the second group Q2, specifically, the stop ST is disposed between the third lens L3 and the fourth lens L4.

The filter G1 is disposed between the third group Q3 and the image plane S18.

In the wide-angle lens 100 provided in this embodiment, the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, the seventh lens L7, and the eighth lens L8 are all made of a glass material, and the second lens L2, the fifth lens L5, and the eighth lens L8 are all made of a glass aspheric lens.

The relevant parameters of each lens in the wide-angle lens 100 provided in the present embodiment are shown in table 1.

TABLE 1

Surface number	Surface type	Radius of curvature	Thickness of	Refractive index	Abbe number
							Article surface	All-round	All-round
S1	Spherical surface	8.819722	0.602392	1.901	37.05
						S2	Spherical surface	2.854768	2.138819
S3	Aspherical surface	-5.726532	1.070475	1.693	53.20
						S4	Aspherical surface	363.784943	1.146690
S5	Spherical surface	-12.385210	0.910028	2.001	25.44
						S6	Spherical surface	-4.731318	0.152955
ST	Diaphragm	All-round	0.569157
						S7	Spherical surface	-5.067608	1.030129	1.456	90.27
S8	Spherical surface	-3.008328	0.458779
						S9	Aspherical surface	7.910199	1.489988	1.593	68.53
S10	Aspherical surface	-6.313031	0.231864
						S11	Spherical surface	-11.756423	0.449960	1.762	26.61
S12	Spherical surface	2.950239	1.924232	1.593	68.53
						S13	Spherical surface	26.757152	0.684653
S14	Aspherical surface	8.172556	1.639889	1.497	81.52
						S15	Aspherical surface	-20.000000	0.953293
S16	Spherical surface	All-round	0.500000	1.517	64.21
						S17	Spherical surface	All-round	2.046704
S18	Image plane	All-round	——

The aspherical surface parameters of each lens of this example are shown in table 2.

TABLE 2

In the present embodiment, the field curvature, distortion, axial chromatic aberration and vertical chromatic aberration are shown in fig. 2, fig. 3, fig. 4 and fig. 5, respectively. As can be seen from fig. 2 to 5, the field curvature, distortion, axial chromatic aberration, and vertical axis chromatic aberration in the present embodiment can be corrected well.

Second embodiment

Please refer to fig. 6 for a schematic structural diagram of a wide-angle lens 200 according to this embodiment. The wide-angle lens 200 in the present embodiment is largely the same as the wide-angle lens 100 in the first embodiment, except that: in the wide-angle lens 200 of the present embodiment, the paraxial position of the image-side surface S11 of the second lens L2 of the first group Q1 is concave, the fifth lens L5 of the second group Q2 is a glass spherical lens, the image-side surface S13 of the seventh lens L7 of the third group Q3 is convex, and the curvature radius and material selection of each lens are different.

The parameters related to the lens elements of the respective lenses of wide-angle lens 200 provided in the present embodiment are shown in table 3.

TABLE 3

The aspherical surface parameters of each lens of this example are shown in table 4.

TABLE 4

In the present embodiment, the field curvature, distortion, axial chromatic aberration and vertical chromatic aberration are shown in fig. 7, 8, 9 and 10, respectively. As can be seen from fig. 7 to 10, the field curvature, distortion, axial chromatic aberration, and vertical chromatic aberration in the present embodiment can be corrected well.

Third embodiment

Please refer to fig. 11 for a schematic structural diagram of a wide-angle lens 300 according to this embodiment. The wide-angle lens 300 in the present embodiment is largely the same as the wide-angle lens 100 in the first embodiment, except that: in the wide-angle lens 300 of the present embodiment, the object-side surface S3 of the second lens L2 of the first group Q1 is a convex surface, the object-side surface S5 of the third lens L3 is a convex surface, the image-side surface S6 of the third lens L3 is a concave surface, the third lens L3 has negative power, the object-side surface S7 of the fourth lens L4 of the second group Q2 is a concave surface, the fifth lens L5 is a glass spherical lens, the object-side surface S9 of the fifth lens L5 is a concave surface, the sixth lens L6 of the third group Q3 has positive power, the negative surface S11 of the sixth lens L6 and the image-side surface S12-1 of the sixth lens L6 are both convex surfaces, the seventh lens L7 has power, the object-side surface S12-2 of the seventh lens L7 and the image-side surface S13 of the seventh lens L7 are both convex surfaces, and the curvature radii and curvature of the materials are different.

The parameters related to the lens pieces of the respective lenses in the wide-angle lens 300 provided in the present embodiment are shown in table 5.

TABLE 5

Surface number	Surface type	Radius of curvature	Thickness of	Refractive index	Abbe number
							Article surface	All-round	All-round
S1	Spherical surface	9.188139	0.595676	1.743	49.24
						S2	Spherical surface	2.497203	2.087965
S3	Aspherical surface	29.912433	0.507404	1.693	53.20
						S4	Aspherical surface	5.136460	0.572831
S5	Spherical surface	7.535142	1.443528	1.851	40.10
						S6	Spherical surface	6.145891	0.668986
ST	Diaphragm	All-round	0.137881
						S7	Spherical surface	31.690277	0.799150	1.851	40.10
S8	Spherical surface	-5.903793	0.698934
						S9	Spherical surface	-28.701839	1.159661	1.623	56.95
S10	Spherical surface	-4.181023	0.199448
						S11	Spherical surface	9.974187	2.244214	1.618	63.41
S12	Spherical surface	-3.164572	0.448927	1.740	28.29
						S13	Spherical surface	6.317043	0.621246
S14	Aspherical surface	6.651930	2.082304	1.497	81.56
						S15	Aspherical surface	-7.665571	0.953293
S16	Spherical surface	All-round	0.500000	1.517	64.21
						S17	Spherical surface	All-round	2.281574
S18	Image plane	All-round	——

The aspherical surface parameters of each lens of this example are shown in table 6.

TABLE 6

In the present embodiment, the field curvature, distortion, axial chromatic aberration, and vertical chromatic aberration are shown in fig. 12, 13, 14, and 15, respectively. As can be seen from fig. 12 to 15, the field curvature, distortion, axial chromatic aberration, and vertical chromatic aberration in the present embodiment can be corrected well.

Fourth embodiment

Please refer to fig. 16 for a schematic structural diagram of a wide-angle lens 400 according to this embodiment. The wide-angle lens 400 in the present embodiment is substantially the same as the wide-angle lens 100 in the first embodiment, except that: in the wide-angle lens 400 of the present embodiment, the fifth lens L5 of the second group Q2 is a glass spherical lens, the object-side surface S9 of the fifth lens L5 is a concave surface, the sixth lens L6 of the third group Q3 has positive power, the object-side surface S11 of the sixth lens L6 and the image-side surface S12 of the sixth lens L6 are both convex surfaces, the seventh lens L7 has negative power, the object-side surface S12 of the seventh lens L7 and the image-side surface S13 of the seventh lens L7 are both concave surfaces, and the curvature radius and material selection of each lens are different.

The parameters related to the lens elements of the respective lenses in the wide-angle lens 400 provided in the present embodiment are shown in table 7.

TABLE 7

The aspherical surface parameters of each lens of this example are shown in table 8.

TABLE 8

In the present embodiment, the field curvature, distortion, axial chromatic aberration, and vertical chromatic aberration are shown in fig. 17, 18, 19, and 20, respectively. As can be seen from fig. 17 to 20, the field curvature, distortion, axial chromatic aberration, and vertical chromatic aberration in the present embodiment can be corrected well.

Table 9 shows the four embodiments and their corresponding optical characteristics, including the system focal length F, F #, the field angle 2 θ, and the total optical length TTL, and the values corresponding to each of the foregoing conditional expressions.

TABLE 9

In the above embodiment, each of the wide-angle lenses provided by the present invention can achieve the following optical indexes: (1) the field angle: 2 theta is more than or equal to 160 degrees; (2) total optical length: TTL is less than or equal to 18 mm; (3) the applicable spectral range is as follows: 400 nm-700 nm.

In summary, in the wide-angle lens provided by the present invention, the first lens of the first group is a meniscus lens, the second lens is a glass aspheric lens, and is mainly used for collecting light and controlling distortion, the third lens uses a high refractive index glass material to correct on-axis aberration, the second group is used for converging light, two lenses share optical power, so as to avoid a situation that tolerance sensitivity is high due to an excessively large optical power of a single lens, and significantly improve assembly yield, the adhesive body composed of the sixth lens and the seventh lens of the third group is used for eliminating chromatic aberration, and the eighth lens is an aspheric lens, so as to effectively correct aberrations such as curvature of field, spherical aberration, and the like and control the exit angle of a main light ray.

Fifth embodiment

Referring to fig. 21, a schematic structural diagram of an imaging apparatus 500 according to the present embodiment includes a wide-angle lens (e.g., the wide-angle lens 100) and an imaging device 510 in any of the embodiments. The imaging element 510 may be a CMOS (Complementary Metal Oxide Semiconductor) image sensor, and may also be a CCD (Charge Coupled Device) image sensor.

The imaging device 500 may be a motion camera, a video camera, a car recorder, or any other type of wide-angle lens-equipped electronic device.

The imaging apparatus 500 provided by the present embodiment includes a wide-angle lens, and since the wide-angle lens has advantages of small distortion, high pixel, large field angle, and low tolerance sensitivity, the imaging apparatus 500 has advantages of higher pixel imaging effect, small distortion, large field angle, and low tolerance sensitivity.

The above examples only show some embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.