CN119335703A

CN119335703A - Optical lens

Info

Publication number: CN119335703A
Application number: CN202411885426.XA
Authority: CN
Inventors: 张力瑶; 章彬炜
Original assignee: Jiangxi Lianyi Optics Co Ltd
Current assignee: Jiangxi Lianyi Optics Co Ltd
Priority date: 2024-12-20
Filing date: 2024-12-20
Publication date: 2025-01-21
Anticipated expiration: 2044-12-20
Also published as: CN119335703B

Abstract

The invention provides an optical lens which sequentially comprises a first lens with negative focal power, a second lens with negative focal power, a third lens with negative focal power, a fourth lens with positive focal power, a fifth lens with positive focal power, a sixth lens with negative focal power, an object side with convex surface, an image side with concave surface, a seventh lens with positive focal power, an object side with convex surface, an image side with convex surface, an eighth lens with negative focal power, an object side with concave surface, an image side with concave surface, a ninth lens with positive focal power, an object side with convex surface and an image side with concave surface from an object side to an imaging surface along an optical axis. The optical lens can improve the imaging quality of the optical lens and has the advantage of excellent imaging quality.

Description

Optical lens

Technical Field

The invention relates to the technical field of imaging lenses, in particular to an optical lens.

Background

At present, with the improvement of shooting requirements of people, a common optical lens cannot meet the imaging requirements of people, a lens capable of realizing ultra-large angle shooting is urgently needed, a fish-eye lens can be well met, and due to the ultra-wide angle shooting characteristic of the fish-eye lens, a real shot picture can accommodate more and wider sceneries and can meet the picture shooting of a large scene range, so that the lens is widely applied to the shooting fields of a moving camera, an unmanned aerial vehicle, panoramic monitoring and the like. However, the conventional fisheye lens generally has the problems that edge compression is large to cause degradation of resolution of a peripheral view field, and distortion of the edge is large to cause serious image distortion, so that the current requirement of large wide-angle high-definition shooting cannot be met.

Disclosure of Invention

In view of the foregoing, an object of the present invention is to provide an optical lens having an advantage of excellent imaging quality.

The invention provides an optical lens, which comprises nine lenses in sequence from an object side to an imaging surface along an optical axis:

The first lens with negative focal power has a convex object side surface and a concave image side surface;

a second lens having negative optical power, the image side surface of which is concave;

The third lens with negative focal power has a concave object side surface and a convex image side surface;

a fourth lens element with positive refractive power having a concave object-side surface and a convex image-side surface;

A fifth lens element with positive refractive power having a convex object-side surface and a concave image-side surface;

A sixth lens element with negative refractive power having a convex object-side surface at a paraxial region and a concave image-side surface;

a seventh lens element with positive refractive power having a convex object-side surface and a convex image-side surface;

An eighth lens element with negative refractive power having a concave object-side surface and a concave image-side surface;

A ninth lens element with positive refractive power having a convex object-side surface and a concave image-side surface;

The total optical length TTL of the optical lens and the effective focal length f of the optical lens meet 8.5< TTL/f <9, and the real image height IH corresponding to the maximum field angle of the optical lens and the total optical length TTL of the optical lens meet 2.5< TTL/IH <2.8.

Further preferably, the effective focal length f of the optical lens, the maximum field angle FOV of the optical lens and the real image height IH corresponding to the maximum field angle of the optical lens satisfy 60 ° < (f×fov)/IH <65 °.

Further preferably, the effective focal length f of the optical lens and the focal length f1 of the first lens meet-6 < f1/f < -3.5, and the effective focal length f of the optical lens and the focal length f2 of the second lens meet-8 < f2/f < -2.

Further preferably, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy f3/f < -40.

Further preferably, the effective focal length f of the optical lens and the focal length f4 of the fourth lens meet 2< f4/f <6, and the effective focal length f of the optical lens and the object side curvature radius R7 of the fourth lens meet-6.5 < R7/f < -4.5.

Further preferably, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy 2.5< f5/f <4, and the effective focal length f of the optical lens and the image side curvature radius R10 of the fifth lens satisfy 6< R10/f <18.

Further preferably, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy-5 < f6/f < -2.

Further preferably, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy 1< f7/f <3.

Further preferably, the effective focal length f of the optical lens and the focal length f8 of the eighth lens satisfy-3 < f8/f < -1.5, and the effective focal length f of the optical lens and the image side curvature radius R16 of the eighth lens satisfy 1.5< R16/f <4.

Further preferably, the effective focal length f of the optical lens and the focal length f9 of the ninth lens satisfy 2< f9/f <18, and the effective focal length f of the optical lens and the image side curvature radius R18 of the ninth lens satisfy 1.5< R18/f <4.

Compared with the prior art, the optical lens provided by the invention adopts nine lenses with specific focal power, and can improve the imaging quality of the optical lens, reduce the aberration and improve the imaging quality of the optical lens through specific surface shape collocation and reasonable focal power distribution, so that the lens has one or more advantages of ultra-large wide angle, small distortion, miniaturization, large image surface and the like.

Drawings

The foregoing and/or additional aspects and advantages of the invention will become apparent and may be better understood from the following description of embodiments taken in conjunction with the accompanying drawings in which:

Fig. 1 is a schematic structural diagram of an optical lens in embodiment 1 of the present invention.

Fig. 2 is a graph showing a field curvature of an optical lens in embodiment 1 of the present invention.

Fig. 3 is an F-Theta distortion graph of the optical lens in example 1 of the present invention.

Fig. 4 is an axial aberration diagram of the optical lens in embodiment 1 of the present invention.

Fig. 5 is a vertical axis chromatic aberration diagram of an optical lens in embodiment 1 of the present invention.

Fig. 6 is a schematic structural diagram of an optical lens in embodiment 2 of the present invention.

Fig. 7 is a graph showing a field curvature of an optical lens in embodiment 2 of the present invention.

Fig. 8 is an F-Theta distortion graph of an optical lens in example 2 of the present invention.

Fig. 9 is an axial aberration diagram of the optical lens in embodiment 2 of the present invention.

Fig. 10 is a graph showing a vertical axis chromatic aberration of an optical lens in embodiment 2 of the present invention.

Fig. 11 is a schematic structural diagram of an optical lens in embodiment 3 of the present invention.

Fig. 12 is a graph showing the field curvature of an optical lens in embodiment 3 of the present invention.

FIG. 13 is a graph showing F-Theta distortion of an optical lens in example 3 of the present invention.

Fig. 14 is an axial aberration diagram of an optical lens in embodiment 3 of the present invention.

Fig. 15 is a graph showing a vertical axis chromatic aberration of an optical lens in embodiment 3 of the present invention.

Fig. 16 is a schematic structural diagram of an optical lens in embodiment 4 of the present invention.

Fig. 17 is a graph showing the field curvature of an optical lens in embodiment 4 of the present invention.

FIG. 18 is a graph showing F-Theta distortion of an optical lens in example 4 of the present invention.

Fig. 19 is an axial aberration diagram of the optical lens in embodiment 4 of the present invention.

Fig. 20 is a graph showing a vertical axis chromatic aberration of an optical lens in embodiment 4 of the present invention.

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

Detailed Description

For a better understanding of the application, various aspects of the application will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed description are merely illustrative of embodiments of the application and are not intended to limit the scope of the application in any way. Like reference numerals refer to like elements throughout the specification. The expression "and/or" includes any and all combinations of one or more of the associated listed items.

It should be noted that in the present specification, the expressions of first, second, third, etc. are only used to distinguish one feature from another feature, and do not represent any limitation on the feature. Accordingly, a first lens discussed below may also be referred to as a second lens or a third lens without departing from the teachings of the present invention.

In the drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for convenience of explanation. In particular, the spherical or aspherical shape shown in the drawings is shown by way of example. That is, the shape of the spherical or aspherical surface is not limited to the shape of the spherical or aspherical surface shown in the drawings. The figures are merely examples and are not drawn to scale.

Herein, the paraxial region refers to a region near the optical axis. If the lens surface is convex and the convex position is not defined, it means that the lens surface is convex at least in the paraxial region, and if the lens surface is concave and the concave position is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the object is referred to as the object side of the lens, and the surface of each lens closest to the imaging plane is referred to as the image side of the lens.

It will be further understood that the terms "comprises," "comprising," "includes," "including," "having," "containing," and/or "including," when used in this specification, specify the presence of stated features, elements, and/or components, but do not preclude the presence or addition of one or more other features, elements, components, and/or groups thereof. Furthermore, when a statement such as "at least one of the following" appears after a list of features that are listed, the entire listed feature is modified instead of modifying a separate element in the list. Furthermore, when describing embodiments of the application, use of "may" means "one or more embodiments of the application. Also, the term "exemplary" is intended to refer to an example or illustration.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

It should be noted that, without conflict, the embodiments of the present application and features of the embodiments may be combined with each other. The application will be described in detail below with reference to the drawings in connection with embodiments.

The optical lens provided by the embodiment of the invention comprises nine lenses in total, wherein the optical lens sequentially comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens and a ninth lens from an object side to an imaging surface along an optical axis.

In some embodiments, the first lens may have a negative optical power, with a convex object-side surface and a concave image-side surface. The second lens element may have negative refractive power, wherein the object-side surface thereof may be concave or convex, and the image-side surface thereof may be concave. The third lens element has a negative refractive power, wherein an object-side surface thereof is concave, and an image-side surface thereof is convex. The fourth lens element may have positive refractive power, wherein an object-side surface thereof is concave and an image-side surface thereof is convex. The fifth lens element may have positive refractive power, wherein an object-side surface thereof is convex and an image-side surface thereof is concave. The sixth lens element with negative refractive power has a convex object-side surface at a paraxial region and a concave image-side surface. The seventh lens element may have positive refractive power, wherein an object-side surface thereof is convex and an image-side surface thereof is convex. The eighth lens element with negative refractive power has a concave object-side surface and a concave image-side surface. The ninth lens element may have positive refractive power, wherein an object-side surface thereof is convex and an image-side surface thereof is concave.

In some embodiments, the optical lens may further include a diaphragm, and the diaphragm may be located between the fourth lens and the fifth lens. It will be appreciated that the aperture is used to limit the amount of light entering to vary the brightness of the image. When the diaphragm is located between the fourth lens and the fifth lens, correction of the diaphragm aberration is facilitated.

In some embodiments, the optical lens may further include an optical filter disposed between the ninth lens element and the imaging surface. The optical filter is used for filtering the interference light and preventing the interference light from reaching the imaging surface of the optical lens to influence normal imaging.

In some embodiments, the optical total length TTL of the optical lens and the effective focal length f of the optical lens satisfy 8.5< TTL/f <9. The length of the lens can be effectively limited by meeting the above conditions, and the miniaturization of the lens can be realized.

In some embodiments, the real image height IH corresponding to the maximum field angle of the optical lens and the total optical length TTL of the optical lens satisfy 2.5< TTL/IH <2.8. Under the condition that the same total length of the lens is ensured, the lens has a larger image surface, can be matched with an imaging chip with a larger size to realize high-definition imaging, and better realizes the balance of the small total length and the large image surface of the lens.

In some embodiments, the effective focal length f of the optical lens, the maximum field angle FOV of the optical lens, and the real image height IH corresponding to the maximum field angle of the optical lens satisfy 60 ° < (f x FOV)/IH <65 °. The method meets the conditions, and is favorable for realizing the balance of the large field angle of the optical lens and the large target surface imaging by reasonably limiting the relation among the focal length, the field angle and the image height of the optical lens.

In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy-6 < f1/f < -3.5. The first lens has larger negative refractive power, so that the light rays with the marginal view field can be collected as much as possible to enter the rear system, and the collection of the light rays with the large angle is realized, thereby realizing the ultra-wide angle imaging of the lens.

In some embodiments, the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy-8 < f2/f < -2. The second lens has negative focal power, and can share the negative focal power of the front end of the optical lens, so that the problem that the deflection of light rays is overlarge due to the fact that the focal power of the first lens is too concentrated is solved, and the difficulty of chromatic aberration correction of the optical lens is reduced.

In some embodiments, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy f3/f < -40. The method meets the conditions, is favorable for smooth transition of light, reduces correction difficulty of aberration and distortion, and improves overall imaging quality.

In some embodiments, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy 2< f4/f <6. The fourth lens has larger positive focal power, can effectively converge a large range of light rays entering the system, avoids overlarge light deflection caused by overlarge concentration of the front negative focal power lens, reduces the correction difficulty of aberration and improves the imaging quality of the optical lens.

In some embodiments, the effective focal length f of the optical lens and the object-side radius of curvature R7 of the fourth lens satisfy-6.5 < R7/f < -4.5. The fourth lens adopts a meniscus shape, thereby being beneficial to better realizing the convergence of light rays, shortening the distance from the light rays to the next lens and reducing the total length of the optical lens.

In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy 2.5< f5/f <4, and the effective focal length f of the optical lens and the image side radius of curvature R10 of the fifth lens satisfy 6< R10/f <18. The lens can further effectively converge light rays, reduce the difficulty of distortion correction of the edge view field, ensure that the lens has small distortion while realizing a large view angle, improve the resolving power of the edge view field and ensure that the lens has higher imaging quality in the whole view field.

In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy-5 < f6/f < -2. The sixth lens element with high negative refractive power is beneficial to reducing the deflection degree of incident light rays, avoiding excessive aberration caused by excessively strong refractive change, balancing various aberrations generated by the front lens group and improving the overall imaging quality.

In some embodiments, the effective focal length f of the optical lens and the focal length f7 of the seventh lens satisfy 1< f7/f <3. The seventh lens has proper positive focal power, so that the coma, astigmatism and field curvature of the optical lens can be balanced, and the imaging quality of the optical lens can be improved.

In some embodiments, the effective focal length f of the optical lens and the focal length f8 of the eighth lens satisfy-3 < f8/f < -1.5, and the effective focal length f of the optical lens and the image side curvature radius R16 of the eighth lens satisfy 1.5< R16/f <4. The light beam of the central view field is favorable for being diverged to a certain extent, the emergence angle of the light beam of the edge view field is reduced by combining the bending of the edge view field, and the relative illumination of the edge view field is improved.

In some embodiments, the effective focal length f of the optical lens and the focal length f9 of the ninth lens satisfy 2< f9/f <18, and the effective focal length f of the optical lens and the image side radius of curvature R18 of the ninth lens satisfy 1.5< R18/f <4. The imaging lens meets the conditions, is beneficial to improving the incidence height of light on the imaging surface, increases the area of the light entering the imaging surface, realizes the imaging of the large target surface of the lens, and improves the imaging quality of the optical lens.

In some embodiments, the effective focal length f of the optical lens and the real image height IH corresponding to the maximum field angle of the optical lens satisfy 3< IH/f <3.5. The wide-angle characteristic can be realized by meeting the conditions, so that the requirement of large-range shooting is met, the characteristic of a large image plane can be realized, and the imaging quality of the optical lens is improved.

In some embodiments, the effective focal length f of the optical lens and the object-side radius of curvature R11 of the sixth lens satisfy 3< R11/f <15, and the effective focal length f of the optical lens and the image-side radius of curvature R12 of the sixth lens satisfy 1< R12/f <2. The method meets the conditions, is beneficial to balancing the field curvature of the optical lens and improves the imaging quality of the optical lens.

In some embodiments, the focal length f1 of the first lens and the focal length f2 of the second lens satisfy 0.3< f1/f2<2. The optical lens meets the conditions, can effectively converge a large range of light rays entering the system, and is beneficial to correcting large-angle aberration by the rear-end optical system, so that miniaturization of the optical lens and high-pixel equalization are realized.

In some embodiments, the focal length f3 of the third lens and the focal length f4 of the fourth lens satisfy-70 < f3/f4< -5. The method meets the conditions, is favorable for smooth transition of light, can better correct distortion of the edge view field, reduces image compression degree of the edge view field, and improves resolution of the edge view field.

In some embodiments, the focal length f5 of the fifth lens and the focal length f6 of the sixth lens satisfy-1.5 < f5/f6< -0.5. The optical lens meets the conditions, is favorable for smooth transition of light, corrects various aberrations of the optical lens, and improves imaging quality of the optical lens.

In some embodiments, the focal length f7 of the seventh lens and the focal length f8 of the eighth lens satisfy-1.3 < f7/f8< -0.5. The optical lens meets the conditions, is favorable for smooth transition of light, corrects various aberrations of the optical lens, and improves imaging quality of the optical lens.

In some embodiments, the object-side effective aperture DM11 of the first lens and the image-side effective aperture DM92 of the ninth lens satisfy 2.2< DM11/DM92<3.2. The lens has larger incident caliber, ensures that as much light as possible enters the system, increases the area of the light entering the imaging surface, and is beneficial to realizing the balance of the large image surface and the large aperture of the lens.

In some embodiments, the combined focal length fb of the fifth, sixth, seventh, eighth, and ninth lenses and the effective focal length f of the optical lens satisfy 2< fb/f <4. The above conditions are satisfied, and the focal length of the lens group behind the diaphragm is reasonably distributed, so that the distortion and astigmatism generated by the lens at the front end of the optical lens are balanced, and the imaging quality of the optical lens is improved.

In some embodiments, the optical lens satisfies the conditional expression of 1.9mm < f <2.1mm,17mm < TTL <18.5mm,190 DEG < FOV <210 DEG, FNo <2.1, 6mm < IH <7mm, wherein f represents the effective focal length of the optical lens, TTL represents the total optical length of the optical lens, FOV represents the maximum field angle of the optical lens, FNo represents the aperture value of the optical lens, IH represents the real image height corresponding to the maximum field angle of the optical lens. The optical lens provided by the embodiment of the invention is favorable for realizing ultra-wide angle characteristics, so that more scene information can be acquired, the requirement of large-scale detection of the optical lens is met, the optical lens has smaller optical total length, the light inlet quantity of the lens is favorable for being improved, the lens can perform high-definition imaging in a dark night environment, the lens has a larger imaging surface, and the lens can be matched with a chip with a larger size to realize high-definition imaging.

In some embodiments, the nine lenses in the optical lens may all be plastic lenses or a glass-plastic mixed material collocation structure, and preferably, the optical lens of the invention adopts a nine-lens glass-plastic mixed collocation lens structure. Specifically, the first lens and the fourth lens are glass lenses, the second lens, the third lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens and the ninth lens are plastic lenses, and the glass-plastic mixed structure is adopted, so that the heat stability can be improved, the cost can be effectively reduced, the aberration can be corrected, the volume can be reduced, and the optical lens product with higher cost performance can be provided.

In some embodiments, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens and the ninth lens may be spherical lenses or aspherical lenses, and compared with spherical structures, the aspherical structures can effectively reduce the aberration of the optical system, so that the number of lenses and the size of the lenses are reduced, and miniaturization of the lens is better achieved. More specifically, in the optical lens provided by the invention, the first lens and the fourth lens can adopt spherical lenses, and the second lens, the third lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens and the ninth lens can adopt aspherical lenses.

In various embodiments of the present invention, when an aspherical lens is used as the lens, each aspherical surface shape of the optical lens satisfies the following equation:

;

Wherein z is the distance between the curved surface and the curved surface vertex in the optical axis direction, h is the distance between the optical axis and the curved surface, c is the curvature of the curved surface vertex, K is the quadric surface coefficient, B, C, D, E, F, G, H is the fourth-order, sixth-order, eighth-order, tenth-order, fourteen-order and sixteen-order curved surface coefficients respectively.

The invention is further illustrated in the following examples. In various embodiments, the thickness, radius of curvature, and material selection portion of each lens in the optical lens may vary, and for specific differences, reference may be made to the parameter tables of the various embodiments. The following examples are merely preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the following examples, and any other changes, substitutions, combinations or simplifications that do not depart from the gist of the present invention are intended to be equivalent substitutes within the scope of the present invention.

Example 1

Referring to fig. 1, a schematic structure of an optical lens 100 according to embodiment 1 of the present invention is shown, where the optical lens 100 includes, in order from an object side to an imaging surface S21 along an optical axis, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a diaphragm ST, a fifth lens L5, a sixth lens L6, a seventh lens L7, an eighth lens L8, a ninth lens L9, and a filter G1.

The first lens element L1 has a negative refractive power, wherein an object-side surface S1 thereof is convex, and an image-side surface S2 thereof is concave;

the second lens element L2 has negative refractive power, wherein an object-side surface S3 thereof is concave at a paraxial region thereof and an image-side surface S4 thereof is concave;

the third lens element L3 has negative refractive power, wherein an object-side surface S5 thereof is concave, and an image-side surface S6 thereof is convex;

the fourth lens element L4 has positive refractive power, wherein an object-side surface S7 thereof is concave, and an image-side surface S8 thereof is convex;

The fifth lens element L5 has positive refractive power, wherein an object-side surface S9 thereof is convex, and an image-side surface S10 thereof is concave;

the sixth lens element L6 has negative refractive power, wherein an object-side surface S11 thereof is convex at a paraxial region and an image-side surface S12 thereof is concave;

the seventh lens element L7 with positive refractive power has a convex object-side surface S13 and a convex image-side surface S14;

The eighth lens element L8 with negative focal power has a concave object-side surface S15 and a concave image-side surface S16;

the ninth lens element L9 with positive refractive power has a convex object-side surface S17 and a concave image-side surface S18;

the object side surface S19 and the image side surface S20 of the optical filter G1 are planes;

The imaging surface S21 is a plane.

The first lens L1 and the fourth lens L4 adopt glass spherical lenses, and the second lens L2, the third lens L3, the fifth lens L5, the sixth lens L6, the seventh lens L7, the eighth lens L8 and the ninth lens L9 adopt plastic aspherical lenses.

The relevant parameters of each lens in the optical lens 100 in embodiment 1 are shown in table 1-1.

TABLE 1-1

The surface profile parameters of the aspherical lens of the optical lens 100 in example 1 are shown in tables 1-2.

TABLE 1-2

In the present embodiment, the field curvature curve, the F-Theta distortion curve, the axial aberration curve, and the vertical axis aberration curve of the optical lens 100 are shown in fig. 2, 3, 4, and 5, respectively.

Fig. 2 shows a field curvature graph in the present embodiment, which represents the field curvature of light rays on a meridional image plane and a sagittal image plane, the horizontal axis represents the amount of shift (unit: mm), and the vertical axis represents the angle of view (unit: °). As can be seen from the figure, the curvature of field of the meridional image plane and the sagittal image plane is controlled within ±0.05mm, which means that the optical lens 100 can correct curvature of field well.

Fig. 3 shows an F-Theta distortion graph in this embodiment, which represents distortion at different view angles on an imaging plane, with the horizontal axis representing distortion values (in:%) and the vertical axis representing view angles (in: °). As can be seen from the figure, the distortion value is controlled within ±8%, which indicates that the optical lens 100 can correct distortion well.

Fig. 4 shows an axial aberration diagram in this embodiment, which represents aberration of each wavelength on the optical axis at the imaging plane, the horizontal axis represents an axial aberration value (unit: mm), and the vertical axis represents a normalized pupil radius. As can be seen from the figure, the axial aberration is controlled to be within ±0.02mm, which means that the optical lens 100 can correct the axial aberration well.

Fig. 5 shows a vertical axis color difference graph in this embodiment, which represents color differences at different image heights on an imaging plane for each wavelength with respect to a center wavelength (0.55 μm), with the horizontal axis representing a vertical axis color difference value (unit: μm) for each wavelength with respect to the center wavelength, and the vertical axis representing a normalized field angle. As can be seen from the figure, the vertical chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±3 μm, indicating that the optical lens 100 can correct the vertical chromatic aberration well.

Example 2

Referring to fig. 6, a schematic structural diagram of an optical lens 200 according to embodiment 2 of the present invention is shown, and the main difference between the present embodiment and embodiment 1 is that the optical parameters such as the radius of curvature and the lens thickness of each lens surface are different.

The relevant parameters of each lens in the optical lens 200 in example 2 are shown in table 2-1.

TABLE 2-1

The surface profile parameters of the aspherical lens of the optical lens 200 in example 2 are shown in table 2-2.

TABLE 2-2

In the present embodiment, the field curvature curve, the F-Theta distortion curve, the axial aberration curve, and the vertical axis aberration curve of the optical lens 200 are shown in fig. 7, 8, 9, and 10, respectively.

As can be seen from fig. 7, the curvature of field of the meridional image plane and the sagittal image plane is controlled within ±0.06mm, which means that the optical lens 200 can correct curvature of field well.

As can be seen from fig. 8, the distortion value is controlled within ±8%, which indicates that the optical lens 200 can correct distortion well.

As can be seen from fig. 9, the axial aberration is controlled to be within ±0.03mm, which means that the optical lens 200 can correct the axial aberration well.

As can be seen from fig. 10, the vertical chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±3 μm, indicating that the optical lens 200 can correct the vertical chromatic aberration well.

Example 3

Referring to fig. 11, a schematic diagram of an optical lens 300 according to embodiment 3 of the present invention is shown, and the main difference between the present embodiment and embodiment 1 is that the optical parameters such as the radius of curvature and the thickness of the lens are different.

The relevant parameters of each lens in the optical lens 300 in example 3 are shown in table 3-1.

TABLE 3-1

The surface profile parameters of the aspherical lens of the optical lens 300 in example 3 are shown in table 3-2.

TABLE 3-2

In the present embodiment, the field curvature curve, the F-Theta distortion curve, the axial aberration curve, and the vertical axis aberration curve of the optical lens 300 are shown in fig. 12, 13, 14, and 15, respectively.

As can be seen from fig. 12, the curvature of field of the meridional image plane and the sagittal image plane is controlled within ±0.2mm, which means that the optical lens 300 can correct curvature of field well.

As can be seen from fig. 13, the distortion value is controlled within ±8%, which indicates that the optical lens 300 can correct distortion well.

As can be seen from fig. 14, the axial aberration is controlled to be within ±0.03mm, which means that the optical lens 300 can correct the axial aberration well.

As can be seen from fig. 15, the vertical chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±3 μm, indicating that the optical lens 300 can correct the vertical chromatic aberration well.

Example 4

Referring to fig. 16, a schematic structural diagram of an optical lens 400 according to embodiment 4 of the present invention is shown, and the main difference between the present embodiment and embodiment 1 is that the object side surface S3 of the second lens element L2 is a convex surface, and the optical parameters such as the radius of curvature and the lens thickness of each lens surface are different.

The relevant parameters of each lens in the optical lens 400 in example 4 are shown in table 4-1.

TABLE 4-1

The surface profile parameters of the aspherical lens of the optical lens 400 in example 4 are shown in table 4-2.

TABLE 4-2

In the present embodiment, the field curvature curve, the F-Theta distortion curve, the axial aberration curve, and the vertical axis aberration curve of the optical lens 400 are shown in fig. 17, 18, 19, and 20, respectively.

As can be seen from fig. 17, the curvature of field of the meridional image plane and the sagittal image plane is controlled within ±0.05mm, which indicates that the optical lens 400 can satisfactorily correct curvature of field.

As can be seen from fig. 18, the distortion value is controlled within ±8%, which indicates that the optical lens 400 can correct distortion well.

As can be seen from fig. 19, the axial aberration is controlled to be within ±0.04mm, which means that the optical lens 400 can correct the axial aberration well.

As can be seen from fig. 20, the vertical chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±3 μm, indicating that the optical lens 400 can correct the vertical chromatic aberration well.

Referring to table 5, the optical characteristics corresponding to the above embodiments include an effective focal length f, an optical total length TTL, an aperture value Fno, a real image height IH corresponding to a maximum field angle, a maximum field angle FOV, and a numerical value corresponding to each conditional expression in each embodiment.

TABLE 5

Compared with the prior art, the optical lens provided by the invention has at least the following advantages:

(1) The optical lens provided by the invention has the advantages that through specific surface shape arrangement and reasonable focal power distribution, the structure of the optical lens is compact, the miniaturization of the optical lens is facilitated, the ultra-large wide angle of the lens can be realized, more scene information can be obtained, and the requirement of large-scale detection of the optical lens is met.

(2) The optical lens provided by the invention has a large image surface, can be well matched with a large-size chip, ensures good analysis quality, and can reasonably correct the integral aberration of the optical lens, so that the optical lens has small distortion and the imaging quality of the optical lens is improved.

(3) The optical lens provided by the invention adopts a glass-plastic mixed matching structure, so that the lens has good thermal stability, the stability of the lens under high and low temperature conditions is improved, and the imaging quality is improved. The production cost of the lens is greatly reduced, the volume of the lens is reduced, and the miniaturization of the lens is better realized.

In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The foregoing examples illustrate only a few embodiments of the invention and are described in detail herein without thereby limiting the scope of the invention. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the invention, which are all within the scope of the invention. Accordingly, the scope of protection of the present invention is to be determined by the appended claims.

Claims

1. An optical lens comprising nine lenses in total, in order from an object side to an imaging plane along an optical axis, comprising:

2. The optical lens according to claim 1, wherein an effective focal length f of the optical lens, a maximum field angle FOV of the optical lens, and a real image height IH corresponding to the maximum field angle of the optical lens satisfy 60 ° < (f x FOV)/IH <65 °.

3. The optical lens of claim 1, wherein an effective focal length f of the optical lens and a focal length f1 of the first lens satisfy-6 < f1/f < -3.5, and an effective focal length f of the optical lens and a focal length f2 of the second lens satisfy-8 < f2/f < -2.

4. The optical lens of claim 1, wherein an effective focal length f of the optical lens and a focal length f3 of the third lens satisfy f3/f < -40.

5. The optical lens as claimed in claim 1, wherein an effective focal length f of the optical lens and a focal length f4 of the fourth lens satisfy 2< f4/f <6, and an effective focal length f of the optical lens and an object side curvature radius R7 of the fourth lens satisfy-6.5 < R7/f < -4.5.

6. The optical lens as claimed in claim 1, wherein an effective focal length f of the optical lens and a focal length f5 of the fifth lens satisfy 2.5< f5/f <4, and an effective focal length f of the optical lens and an image side curvature radius R10 of the fifth lens satisfy 6< R10/f <18.

7. The optical lens of claim 1, wherein the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy-5 < f6/f < -2.

8. The optical lens of claim 1, wherein an effective focal length f of the optical lens and a focal length f7 of the seventh lens satisfy 1< f7/f <3.

9. The optical lens of claim 1, wherein an effective focal length f of the optical lens and a focal length f8 of the eighth lens satisfy-3 < f8/f < -1.5, and an effective focal length f of the optical lens and an image side curvature radius R16 of the eighth lens satisfy 1.5< R16/f <4.

10. The optical lens as claimed in claim 1, wherein an effective focal length f of the optical lens and a focal length f9 of the ninth lens satisfy 2< f9/f <18, and an effective focal length f of the optical lens and an image side curvature radius R18 of the ninth lens satisfy 1.5< R18/f <4.