Optical lens

Abstract

The application provides an optical lens, which comprises seven lenses in sequence along an optical axis from an object side to an imaging surface, and the seven lenses comprise: a first lens with negative optical power, wherein the object side surface of the first lens is a convex surface, and the image side surface of the first lens is a concave surface; a second lens with negative optical power, wherein the object side surface and the image side surface of the second lens are both concave surfaces; a third lens with positive optical power, wherein the object side surface and the image side surface of the third lens are both convex surfaces; a fourth lens with positive optical power, wherein the object side surface of the fourth lens is a convex surface, and the image side surface of the fourth lens is a concave surface; a fifth lens with positive optical power, wherein the object side surface and the image side surface of the fifth lens are both convex surfaces; a sixth lens with negative optical power, wherein the object side surface and the image side surface of the sixth lens are both concave surfaces; and a seventh lens with positive optical power, wherein the object side surface and the image side surface of the seventh lens are both convex surfaces. The optical lens provided by the application has one or more advantages, such as a large aperture, a large field of view, high imaging quality and the like, through specific surface shape matching and reasonable optical power distribution.

Description

Technical Field

[0001] This invention relates to the technical field of imaging lenses, and in particular to an optical lens. Background Technology

[0002] As people's demands for driving experience continue to increase, automotive optical lenses are being used more and more in intelligent driving, and the status of automotive optical lenses in the automotive industry is constantly rising.

[0003] Advanced Driver Assistance Systems (ADAS) play a crucial role in intelligent driving. They use various cameras and sensors to collect environmental information to ensure driver safety. For example, typically, a surround-view camera is installed in each of the four directions (front, rear, left, and right) of a vehicle. By stitching together the images captured by these four cameras, a 360-degree panoramic view of the vehicle's surroundings can be provided to the driver. With the rapid development of ADAS, the requirements for surround-view cameras are also increasing. Therefore, it is necessary to develop an optical lens with high imaging quality. Summary of the Invention

[0004] To address the aforementioned problems, the present invention aims to provide an optical lens with the advantage of excellent image quality.

[0005] The technical solution adopted in this invention is as follows:

[0006] An optical lens comprises seven lenses, arranged sequentially along the optical axis from the object side to the imaging plane:

[0007] The first lens with negative optical power has a convex object side and a concave image side.

[0008] A second lens with negative optical power has concave object-side and image-side surfaces;

[0009] A third lens with positive optical power has convex surfaces on both its object side and image side.

[0010] The fourth lens with positive optical power has a convex object side and a concave image side.

[0011] The fifth lens with positive optical power has both its object-side surface and image-side surface being convex.

[0012] The sixth lens has negative optical power, and both its object-side and image-side surfaces are concave.

[0013] The seventh lens with positive optical power has convex surfaces on both its object side and image side.

[0014] Among them, the radius of curvature R12 of the image side surface of the sixth lens and the radius of curvature R14 of the image side surface of the seventh lens satisfy: 0 < (R12 + R14) / (R12 - R14) < 1; the radius of curvature R8 of the image side surface of the fourth lens and the effective focal length f of the optical lens satisfy: R8 / f > 3.

[0015] Further preferably, the maximum field angle FOV of the optical lens and the aperture value FNO of the optical lens satisfy: FOV / FNO > 110°.

[0016] Further preferably, the true image height IH corresponding to the maximum field angle of the optical lens and the effective focal length f of the optical lens satisfy: 3.5 < IH / f < 4.7.

[0017] Further preferably, the focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: 7 < f4 / f < 16.

[0018] Further preferably, the radius of curvature R9 of the object side surface of the fifth lens and the effective focal length f of the optical lens satisfy: 3 < R9 / f < 12.

[0019] Further preferably, the radius of curvature R13 of the object side surface of the seventh lens and the effective focal length f of the optical lens satisfy: 3 < R13 / f < 5.

[0020] Further preferably, the radius of curvature R7 of the object side surface of the fourth lens and the radius of curvature R8 of the image side surface of the fourth lens satisfy: -1 < (R7 - R8) / (R7 + R8) < 0.

[0021] Further preferably, the combined focal length f1234 of the first lens, the second lens, the third lens and the fourth lens and the combined focal length f567 of the fifth lens, the sixth lens and the seventh lens satisfy: 0.4 < f1234 / f567 < 1.2.

[0022] Further preferably, the sagittal height Sag8 of the clear aperture semi-diameter of the image side surface of the fourth lens satisfies: 0 < Sag8 < 0.2 mm; the sagittal height Sag12 of the clear aperture semi-diameter of the image side surface of the sixth lens satisfies: 0 < Sag12 < 0.3 mm.

[0023] Further preferably, the spacing CT23 of the second lens and the third lens on the optical axis, the spacing CT34 of the third lens and the fourth lens on the optical axis, and the central thickness CT4 of the fourth lens satisfy: 1.5 < CT23 / (CT34 + CT4) < 3.5.

[0024] The optical lens provided by this invention uses seven lenses with specific optical power. Through specific surface shape matching and reasonable optical power distribution, it can improve the imaging quality of the optical lens, reduce aberrations, and enhance the imaging quality of the optical lens, giving the lens one or more advantages such as large aperture, large field of view, and high imaging quality. Attached Figure Description

[0025] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0026] Figure 1 This is a schematic diagram of the optical lens structure in Embodiment 1 of the present invention.

[0027] Figure 2 This is a field curvature curve diagram of the optical lens in Embodiment 1 of the present invention.

[0028] Figure 3 This is the F-θ distortion curve of the optical lens in Embodiment 1 of the present invention.

[0029] Figure 4 This is the MTF curve of the optical lens in Embodiment 1 of the present invention at an operating temperature of 20°C.

[0030] Figure 5 This is the MTF curve of the optical lens in Embodiment 1 of the present invention at an operating temperature of -40℃.

[0031] Figure 6 This is the MTF curve of the optical lens in Embodiment 1 of the present invention at an operating temperature of 85°C.

[0032] Figure 7 This is an axial aberration curve of the optical lens in Embodiment 1 of the present invention.

[0033] Figure 8 This is a chromatic aberration curve of the optical lens in Embodiment 1 of the present invention.

[0034] Figure 9 This is a schematic diagram of the optical lens structure in Embodiment 2 of the present invention.

[0035] Figure 10 This is a field curvature curve diagram of the optical lens in Embodiment 2 of the present invention.

[0036] Figure 11 This is the F-θ distortion curve of the optical lens in Embodiment 2 of the present invention.

[0037] Figure 12 This is the MTF curve of the optical lens in Embodiment 2 of the present invention at an operating temperature of 20°C.

[0038] Figure 13This is the MTF curve of the optical lens in Embodiment 2 of the present invention at an operating temperature of -40℃.

[0039] Figure 14 This is the MTF curve of the optical lens in Embodiment 2 of the present invention at an operating temperature of 85°C.

[0040] Figure 15 This is an axial aberration curve of the optical lens in Embodiment 2 of the present invention.

[0041] Figure 16 This is a chromatic aberration curve of the optical lens in Embodiment 2 of the present invention.

[0042] Figure 17 This is a schematic diagram of the optical lens in Embodiment 3 of the present invention.

[0043] Figure 18 This is a field curvature curve diagram of the optical lens in Embodiment 3 of the present invention.

[0044] Figure 19 This is the F-θ distortion curve of the optical lens in Embodiment 3 of the present invention.

[0045] Figure 20 This is the MTF curve of the optical lens in Embodiment 3 of the present invention at an operating temperature of 20°C.

[0046] Figure 21 This is the MTF curve of the optical lens in Embodiment 3 of the present invention at an operating temperature of -40℃.

[0047] Figure 22 This is the MTF curve of the optical lens in Embodiment 3 of the present invention at an operating temperature of 85°C.

[0048] Figure 23 This is an axial aberration curve of the optical lens in Embodiment 3 of the present invention.

[0049] Figure 24 This is a chromatic aberration curve of the optical lens in Embodiment 3 of the present invention.

[0050] Figure 25 This is a schematic diagram of the optical lens structure in Embodiment 4 of the present invention.

[0051] Figure 26 This is a field curvature curve diagram of the optical lens in Embodiment 4 of the present invention.

[0052] Figure 27 This is the F-θ distortion curve of the optical lens in Embodiment 4 of the present invention.

[0053] Figure 28 This is the MTF curve of the optical lens in Embodiment 4 of the present invention at an operating temperature of 20°C.

[0054] Figure 29 This is the MTF curve of the optical lens in Embodiment 4 of the present invention at an operating temperature of -40℃.

[0055] Figure 30 This is the MTF curve of the optical lens in Embodiment 4 of the present invention at an operating temperature of 85°C.

[0056] Figure 31 This is an axial aberration curve of the optical lens in Embodiment 4 of the present invention.

[0057] Figure 32 This is a chromatic aberration curve of the optical lens in Embodiment 4 of the present invention.

[0058] The following detailed description, in conjunction with the accompanying drawings, will further illustrate the present invention. Detailed Implementation

[0059] To better understand this application, various aspects of this application will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed descriptions are merely illustrative of embodiments of this application and are not intended to limit the scope of this application in any way. Throughout the specification, the same reference numerals refer to the same elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0060] It should be noted that in this specification, the terms "first," "second," "third," etc., are used only to distinguish one feature from another and do not imply any limitation on the features. Therefore, without departing from the teachings of the invention, the first lens discussed below may also be referred to as the second lens or the third lens.

[0061] In the accompanying drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for ease of illustration. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are illustrated by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustrative purposes only and are not strictly to scale.

[0062] In this article, "near the optical axis" refers to the region near the optical axis. If the lens surface is convex and its location is not defined, it means that the lens surface is convex at least near the optical axis; if the lens surface is concave and its location is not defined, it means that the lens surface is concave at least near the optical axis. The surface of each lens closest to the subject is called the object-side surface of the lens, and the surface of each lens closest to the imaging plane is called the image-side surface of the lens.

[0063] It should also be understood that the terms "comprising," "including," "having," "containing," and / or "comprising," when used in this specification, indicate the presence of the stated features, elements, and / or components, but do not exclude the presence or addition of one or more other features, elements, components, and / or combinations thereof. Furthermore, when expressions such as "at least one of..." appear after a list of listed features, they modify the entire list of features, not individual elements in the list. Additionally, when describing embodiments of this application, the word "may" is used to mean "one or more embodiments of this application." And the term "exemplary" is intended to refer to an example or illustration.

[0064] Unless otherwise specified, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It should also be understood that terms (e.g., those defined in common dictionaries) shall be interpreted as having the meaning consistent with their meaning in the context of the relevant art and shall not be interpreted in an idealized or overly formal sense unless expressly so specified herein.

[0065] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0066] The optical lens provided in this embodiment of the invention consists of seven lenses, which are arranged sequentially along the optical axis from the object side to the imaging plane as a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens.

[0067] In some embodiments, the first lens may have negative optical power, with its object-side surface being convex and its image-side surface being concave. The second lens may have negative optical power, with both its object-side and image-side surfaces being concave. The third lens may have positive optical power, with both its object-side and image-side surfaces being convex. The fourth lens may have positive optical power, with its object-side surface being convex and its image-side surface being concave. The fifth lens may have positive optical power, with both its object-side and image-side surfaces being convex. The sixth lens may have negative optical power, with both its object-side and image-side surfaces being concave. The seventh lens may have positive optical power, with both its object-side and image-side surfaces being convex.

[0068] In some embodiments, the optical lens may also include an aperture stop, which may be located between the fourth and fifth lenses. It is understood that the aperture stop can be used to limit the amount of light entering the lens, thereby changing the brightness of the image. Furthermore, when the aperture stop is located between the fourth and fifth lenses, it can rationally allocate the functions of the first to seventh lenses. For example, the first, second, third, and fourth lenses can be used to receive light to a greater extent, while the fifth to seventh lenses can be used to correct aberrations, which is beneficial for balancing the overall structure of the optical system. In addition, when the aperture stop is located between the fourth and fifth lenses, it facilitates the correction of aperture aberrations.

[0069] In some embodiments, the optical lens may further include a filter and a protective glass, which are sequentially disposed between the seventh lens and the imaging plane along the optical axis. The filter is used to filter out interfering light, preventing it from reaching the imaging plane of the optical lens and affecting normal imaging. The protective glass protects the optical lens, preventing damage to the image sensor, and improves the lens's shock and scratch resistance, while having almost no impact on the image quality.

[0070] In some embodiments, the radius of curvature R12 of the image-side surface of the sixth lens and the radius of curvature R14 of the image-side surface of the seventh lens satisfy: 0 < (R12 + R14) / (R12 - R14) < 1. Satisfying this range improves the imaging quality of the optical lens, enabling it to maintain good imaging quality in both high and low temperature environments. Preferably, 0.4 < (R12 + R14) / (R12 - R14) < 0.7.

[0071] In some embodiments, the radius of curvature R8 of the image-side surface of the fourth lens satisfies the condition R8 / f > 3 with respect to the effective focal length f of the optical lens. Meeting this range improves the imaging quality of the optical lens, ensuring good imaging quality even in high and low temperature environments. Preferably, 9 <R8 / f<254。

[0072] In some embodiments, the maximum field of view (FOV) and aperture value (FNO) of the optical lens satisfy the condition: FOV / FNO > 110°. Meeting this range, by reasonably limiting the field of view and aperture value of the optical lens, facilitates expanding the field of view and increasing the aperture, enabling the optical lens to acquire more scene information and meeting the needs of large-area detection. The large aperture characteristic also helps to mitigate the problem of rapid brightness decrease at the edges of the field of view, thus further facilitating the acquisition of more scene information. Preferably, FOV / FNO > 111°.

[0073] In some embodiments, the true image height IH corresponding to the maximum field angle of the optical lens and the effective focal length f of the optical lens satisfy: 3.5 < IH / f < 4.7. Meeting the above range helps the optical lens achieve the characteristics of a large image plane and improve the imaging quality of the optical lens. Preferably, 3.9 < IH / f < 4.3.

[0074] In some embodiments, the focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: 7 < f4 / f < 16. Meeting the above range can further converge light by reasonably limiting the proportion of the focal length of the fourth lens, making the light trend stable. Preferably, 8.2 < f4 / f < 14.6.

[0075] In some embodiments, the radius of curvature R9 of the object side surface of the fifth lens and the effective focal length f of the optical lens satisfy: 3 < R9 / f < 12. Meeting the above range can effectively reduce the field curvature and the difficulty of aberration correction of subsequent lenses by reasonably limiting the shape of the object side surface of the fifth lens and the effective focal length of the optical lens, and improve the imaging quality. Preferably, 4.1 < R9 / f < 11.5.

[0076] In some embodiments, the radius of curvature R13 of the object side surface of the seventh lens and the effective focal length f of the optical lens satisfy: 3 < R13 / f < 5. Meeting the above range can effectively reduce aberrations and improve the imaging quality by reasonably limiting the shape of the object side surface of the seventh lens and the effective focal length of the optical lens. Preferably, 3.7 < R13 / f < 4.4.

[0077] In some embodiments, the radius of curvature R7 of the object side surface of the fourth lens and the radius of curvature R8 of the image side surface of the fourth lens satisfy: -1 < (R7 - R8) / (R7 + R8) < 0. Meeting the above range can effectively control the light trend of the edge field of view and improve the imaging quality of the edge field of view by reasonably limiting the shapes of the object side surface and the image side surface of the fourth lens. Preferably, -1 < (R7 - R8) / (R7 + R8) < -0.2.

[0078] In some embodiments, the combined focal length f1234 of the first lens, the second lens, the third lens and the fourth lens and the combined focal length f567 of the fifth lens, the sixth lens and the seventh lens satisfy: 0.4 < f1234 / f567 < 1.2. Meeting the above range can reasonably distribute the proportion of the optical power of each lens of the optical lens by reasonably limiting the focal length ratio of the front lens group and the rear lens group, and improve the structural stability of the optical lens. Preferably, 0.6 < f1234 / f567 < 1.1.

[0079] In some embodiments, the sagittal height Sag8 of the image side clear aperture of the fourth lens satisfies: 0 < Sag8 < 0.2 mm; the sagittal height Sag12 of the image side clear aperture of the sixth lens satisfies: 0 < Sag12 < 0.3 mm. By reasonably defining the sagittal height of the image side clear aperture of the fourth lens and the sagittal height of the image side clear aperture of the sixth lens within the above ranges, the light path of the marginal field of view can be effectively controlled, and the detailed information of the central field of view of the optical lens can be highlighted. Preferably, 0 < Sag8 < 0.07 mm; 0.09 mm < Sag12 < 0.21 mm.

[0080] In some embodiments, the spacing CT23 between the second lens and the third lens on the optical axis, the spacing CT34 between the third lens and the fourth lens on the optical axis, and the central thickness CT4 of the fourth lens satisfy: 1.5 < CT23 / (CT34 + CT4) < 3.5. By reasonably defining the spacing between the second lens and the third lens on the optical axis, the spacing between the third lens and the fourth lens on the optical axis, and the central thickness of the fourth lens within the above ranges, the spacing between each lens can be reasonably controlled within a reasonable range, enabling each lens to be reasonably arranged within the optical system, reducing the assembly difficulty, and improving the yield. Preferably, 1.8 < CT23 / (CT34 + CT4) < 3.0.

[0081] In some embodiments, the back focal length BFL of the optical lens and the effective focal length f of the optical lens satisfy: BFL / f > 2.2. By reasonably defining the back focal length of the optical lens within the above range, the design and assembly difficulty of the optical lens can be reduced, and the yield can be improved. Preferably, BFL / f > 2.25.

[0082] In some embodiments, the focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: -17 < f1 / f < -5. By reasonably defining the proportion of the focal length of the first lens within the above range, it is helpful to capture light at large angles, allowing as much light as possible to enter the lens and increasing the field angle of the optical lens. Preferably, -6.5 < f1 / f < -5.8.

[0083] In some embodiments, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: -2.9 < f2 / f < -2.1. By reasonably defining the proportion of the focal length of the second lens within the above range, the negative optical power of the front-end lens can be shared, reducing the difficulty of aberration correction for subsequent lenses. Preferably, -2.7 < f2 / f < -2.4.

[0084] In some embodiments, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 3.9 < f3 / f < 5.7. By appropriately defining the proportion of the focal length of the third lens within the above range, the light deflection can be slowed down, reducing the difficulty of aberration correction for subsequent lenses. Preferably, 4.4 < f3 / f < 5.2.

[0085] In some embodiments, the focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy: 1.8 < f5 / f < 2.5. By reasonably defining the proportion of the focal length of the fifth lens within the above range, the lens aberrations can be balanced and the imaging quality can be improved. Preferably, 1.8 < f5 / f < 2.4.

[0086] In some embodiments, the focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: -1.9 < f6 / f < -1.3. By reasonably defining the proportion of the focal length of the sixth lens within the above range, the imaging area can be increased and the imaging quality can be improved. Preferably, -1.7 < f6 / f < -1.3.

[0087] In some embodiments, the focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: 2.3 < f7 / f < 2.8. By reasonably defining the proportion of the focal length of the seventh lens within the above range, the spherical aberration can be optimized and the imaging quality can be enhanced. Preferably, 2.5 < f7 / f < 2.7.

[0088] In some embodiments, the fifth lens and the sixth lens form a cemented lens group with a negative optical power, and the image side of the fifth lens and the object side of the sixth lens are cemented surfaces. Meeting the above range can effectively correct the chromatic aberration of the optical lens, reduce the eccentricity sensitivity of the optical lens, balance the aberrations of the optical lens, and improve the imaging quality of the optical lens; it can also reduce the assembly sensitivity of the optical lens, thereby reducing the processing difficulty of the optical lens and improving the assembly yield of the optical lens. In some embodiments, the combined focal length f56 of the fifth lens and the sixth lens and the effective focal length f of the optical lens satisfy: -16 < f56 / f < -5. Preferably, -14.2 < f56 / f < -5.9.

[0089] In some embodiments, the radius of curvature R12 of the image side of the sixth lens and the effective focal length f of the optical lens satisfy: 5 < R12 / f < 12. Meeting the above range can reduce the high-order aberrations and achieve high-quality imaging. Preferably, 6.1 < R12 / f < 10.6.

[0090] In some embodiments, the radius of curvature R14 of the image side of the seventh lens and the effective focal length f of the optical lens satisfy: -3 < R14 / f < -2. Meeting the above range helps to increase the image plane and improve the imaging quality of the optical lens. Preferably, -2.4 < R14 / f < -2.2.

[0091] In some embodiments, the radius of curvature R9 of the object side surface of the fifth lens and the radius of curvature R10 of the image side surface of the fifth lens satisfy: 0 < (R9 + R10) / (R9 - R10) < 1. By reasonably defining the shapes of the object side surface and the image side surface of the fifth lens within the above range, the field curvature can be reduced and the imaging quality of the optical lens can be improved. Preferably, 0.3 < (R9 + R10) / (R9 - R10) < 0.8.

[0092] In some embodiments, the radius of curvature R11 of the object side surface of the sixth lens and the radius of curvature R12 of the image side surface of the sixth lens satisfy: -1 < (R11 + R12) / (R11 - R12) < 0. By reasonably defining the shapes of the object side surface and the image side surface of the sixth lens within the above range, the aberration can be reduced and the imaging quality of the optical lens can be improved. Preferably, -0.8 < (R11 + R12) / (R11 - R12) < -0.5.

[0093] In some embodiments, the radius of curvature R13 of the object side surface of the seventh lens and the radius of curvature R14 of the image side surface of the seventh lens satisfy: 0 < (R13 + R第十四条) / (R13 - R14) < 1. By reasonably defining the shapes of the object side surface and the image side surface of the seventh lens within the above range, the image plane can be enlarged and the imaging quality of the optical lens can be improved. Preferably, 0.2 < (R13 + R14) / (R13 - R14) < 0.4.

[0094] In some embodiments, the clear aperture radius d1 of the object side surface of the first lens, the true image height IH corresponding to the maximum field angle of the optical lens, and the maximum field angle FOV of the optical lens satisfy: -1 < d1 / (IH / 2) / tan(FOV / 2) < -0.4. By reasonably defining the front aperture diameter, the true image height, and the maximum field angle of the optical lens within the above range, the overall geometric shape of the optical lens can be reasonably arranged and its structural stability can be improved. Preferably, -0.9 < d1 / (IH / 2) / tan(FOV / 2) < -0.5.

[0095] In some embodiments, the overall optical length TTL of the optical lens and the sum ∑CT of the central thicknesses of the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens satisfy: 1.5 < TTL / ∑CT < 2.2. Meeting the above range helps the optical lens achieve high pixel characteristics and improve the imaging quality of the optical lens. Preferably, 1.7 < TTL / ∑CT < 2.0.

[0096] In some embodiments, the distance CT45 between the fourth lens and the fifth lens on the optical axis and the distance CT67 between the sixth lens and the seventh lens on the optical axis satisfy: 1.4 < CT45 / CT67 < 3.5. Meeting the above range helps with the assembly and installation of each lens and improves the yield rate. Preferably, 1.6 < CT45 / CT67 < 3.3.

[0097] In some embodiments, the central thickness CT3 of the third lens and the central thickness CT4 of the fourth lens satisfy: 3 < CT3 / CT4 < 7.5. Meeting the above range reasonably configures the central thickness of each lens and is beneficial to meeting the processability and manufacturability requirements of the optical lens. Preferably, 3.7 < CT3 / CT4 < 7.0.

[0098] In some embodiments, the optical lens satisfies the following conditional expressions: 0.9 mm < f < 1.1 mm; FOV > 198°; 0.4 mm < EPD < 0.6 mm; 15 mm < TTL < 17 mm; 1.7 < FNO < 1.9; 3.8 mm < IH < 4.2 mm; 9° < CRA < 15°; BFL > 2.2 mm. In the above conditional expressions, f represents the effective focal length of the optical lens, FOV represents the maximum field angle of the optical lens, EPD represents the entrance pupil diameter of the optical lens, TTL represents the total optical length of the optical lens, FNO represents the aperture value of the optical lens, IH represents the true image height corresponding to the maximum field angle of the optical lens, CRA represents the chief ray incident angle at the maximum image height of the optical lens, and BFL represents the back focal length of the optical lens. Meeting the above range, the optical lens has at least one or more advantages such as a large target surface, a large aperture, and a large field angle.

[0099] In some embodiments, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens can adopt spherical lenses or aspherical lenses. Compared with the spherical structure, the aspherical structure can effectively reduce the aberration of the optical system, thereby reducing the number of lenses and the size of the lenses, and better realizing the miniaturization of the lens. More specifically, the first lens, the fourth lens, the fifth lens, and the sixth lens of the present invention adopt spherical lenses, and the second lens, the third lens, and the seventh lens adopt aspherical lenses.

[0100] In various embodiments of the present invention, when the lens adopts an aspherical lens, the surface shapes of the aspherical surfaces of the optical lens satisfy the following equation:

[0101]

[0102] Among them, z is the distance between the curved surface and the vertex of the curved surface in the optical axis direction, h is the distance from the optical axis to the curved surface, c is the curvature of the vertex of the curved surface, K is the conic coefficient, and B, C, D, E, and F are the fourth-order, sixth-order, eighth-order, tenth-order, and twelfth-order surface coefficients respectively.

[0103] The present invention will be further described below with reference to several embodiments. In each embodiment, the thickness, radius of curvature, and material selection of each lens in the optical lens are different; for specific differences, please refer to the parameter tables of each embodiment. The following embodiments are merely preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the following embodiments. Any changes, substitutions, combinations, or simplifications made without departing from the innovative points of the present invention should be considered equivalent substitutions and are included within the protection scope of the present invention.

[0104] Example 1

[0105] Please see Figure 1 The diagram shows a schematic of the structure of the optical lens 100 provided in Embodiment 1 of the present invention. The optical lens 100 includes, along the optical axis from the object side to the imaging plane, the following components in sequence: a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, an aperture ST, a fifth lens L5, a sixth lens L6, a seventh lens L7, a filter G1, and a protective glass G2.

[0106] Among them, the first lens L1 has negative optical power, its object side S1 is convex, and its image side S2 is concave.

[0107] The second lens L2 has negative optical power, and its object side surface S3 and image side surface S4 are both concave.

[0108] The third lens L3 has positive optical power, and its object side S5 and image side S6 are both convex surfaces.

[0109] The fourth lens L4 has positive optical power, its object side S7 is convex, and its image side S8 is concave.

[0110] The fifth lens L5 has positive optical power, and both its object side surface S9 and image side surface S10 are convex.

[0111] The sixth lens L6 has negative optical power, and both its object side surface S10 and image side surface S11 are concave.

[0112] The fifth lens L5 and the sixth lens L6 form a cemented lens group with negative optical power, that is, the cemented surface of the image side of the fifth lens L5 and the object side of the sixth lens L6 is S10.

[0113] The seventh lens L7 has positive optical power, and both its object-side surface S12 and image-side surface S13 are convex.

[0114] The object-side surface S14 and the image-side surface S15 of filter G1 are both planar.

[0115] The object side S16 and image side S17 of the protective glass G2 are both flat.

[0116] The imaging plane S18 is a plane.

[0117] The first lens L1, the fourth lens L4, the fifth lens L5, and the sixth lens L6 are glass spherical lenses, while the second lens L2, the third lens L3, and the seventh lens L7 are glass aspherical lenses.

[0118] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0119] Table 1-1

[0120]

[0121]

[0122] The surface profile parameters of the aspherical lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0123] Table 1-2

[0124] Face number K B C D E F S3 1.50E+02 1.07E-02 -3.54E-03 5.26E-04 -4.12E-05 1.43E-06 S4 -6.02E-01 5.85E-03 1.62E-02 -1.39E-02 3.98E-03 -7.17E-04 S5 2.99E+00 -4.19E-03 6.32E-03 -5.88E-03 2.41E-03 -4.73E-04 S6 5.82E+00 -2.93E-03 2.79E-03 -2.40E-03 6.59E-04 -2.09E-05 S12 1.58E-01 -3.52E-02 7.93E-03 -2.64E-03 3.31E-04 8.33E-07 S13 -7.72E-01 4.69E-03 -3.90E-03 1.95E-03 -6.33E-04 6.28E-05

[0125] In this embodiment, the field curvature curve, F-θ distortion curve, MTF curve, axial aberration curve, and transverse chromatic aberration curve of the optical lens 100 at operating temperatures of 20°C, -40°C, and 85°C are respectively as follows: Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 and Figure 8 As shown.

[0126] Figure 2 The field curvature curve of Example 1 is shown, which represents the degree of curvature of light of different wavelengths in the meridional and sagittal image planes. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the half field of view (unit: °). As can be seen from the figure, the field curvature of the meridional and sagittal image planes is controlled within -0.05 mm to 0.04 mm, indicating that the optical lens can effectively correct the field curvature.

[0127] Figure 3 The F-θ distortion curve of Example 1 is shown, which represents the F-θ distortion of light of different wavelengths at different image heights on the imaging plane. The horizontal axis represents the F-θ distortion value (unit: %), and the vertical axis represents the half field of view (unit: °). As can be seen from the figure, the F-θ distortion of the optical lens is controlled within 0 to 16%, and the image compression in the edge angle region is relatively smooth, effectively improving the sharpness of the unfolded image.

[0128] Figure 4The diagram shows the MTF (Modulation Transfer Function) curve of Example 1 at an operating temperature of 20°C. It represents the lens imaging modulation at different spatial frequencies in various fields of view. The horizontal axis represents spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. As can be seen from the figure, the MTF value of this example is above 0.4 across the entire field of view. Within the range of 0–160 lp / mm, the MTF curve decreases smoothly and uniformly from the center to the edge of the field of view, exhibiting good image quality and good detail resolution even at room temperature.

[0129] Figure 5 The diagram shows the MTF (modulation transfer function) curve of Example 1 at an operating temperature of -40°C. It represents the lens imaging modulation at different spatial frequencies in various fields of view. The horizontal axis represents spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. As can be seen from the figure, the MTF value of this example is above 0.35 across the entire field of view. Within the range of 0–160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, demonstrating good image quality and detail resolution even at low temperatures.

[0130] Figure 6 The diagram shows the MTF (Modulation Transfer Function) curve of Example 1 at an operating temperature of 85°C. It represents the lens imaging modulation at different spatial frequencies in various fields of view. The horizontal axis represents spatial frequency (unit: lp / mm), and the vertical axis represents the MTF value. As can be seen from the figure, the MTF value of this example is above 0.2 across the entire field of view. Within the range of 0–160 lp / mm, the MTF curve decreases smoothly and uniformly from the center to the edge of the field of view, demonstrating good image quality and detail resolution even at high temperatures.

[0131] Figure 7 The diagram shows the axial aberration curves for Example 1, representing the aberrations of each wavelength along the optical axis at the imaging plane. The horizontal axis represents the axial aberration value (unit: mm), and the vertical axis represents the normalized pupil radius. The diagram shows that the axial aberration offset is controlled within ±0.01 mm, indicating that the optical lens can effectively correct axial aberrations.

[0132] Figure 8 The diagram shows the transverse chromatic aberration curves for Example 1, representing the chromatic aberration of each wavelength relative to the center wavelength (0.55 μm) at different image heights on the imaging plane. The horizontal axis represents the transverse chromatic aberration value of each wavelength relative to the center wavelength (unit: μm), and the vertical axis represents the normalized field of view. As can be seen from the diagram, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within -2 μm to 5 μm, indicating that the optical lens can excellently correct chromatic aberration at the edge of the field of view and the secondary spectrum of the entire image plane.

[0133] Example 2

[0134] Please see Figure 9 The figure shown is a schematic diagram of the structure of the optical lens 200 provided in Embodiment 2 of the present invention. The main difference between this embodiment and Embodiment 1 is that the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0135] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0136] Table 2-1

[0137]

[0138]

[0139] The surface profile parameters of the aspherical lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0140] Table 2-2

[0141] Face number K B C D E F S3 1.50E+02 1.36E-02 -4.62E-03 7.13E-04 -5.72E-05 1.97E-06 S4 -5.84E-01 1.32E-02 1.75E-02 -1.47E-02 4.08E-03 -6.26E-04 S5 4.50E+00 -2.97E-03 6.56E-03 -5.38E-03 2.04E-03 -3.53E-04 S6 1.03E+01 4.32E-03 -2.06E-03 4.01E-03 -2.42E-03 6.25E-04 S12 -5.11E+00 -3.38E-02 1.05E-02 -6.63E-03 1.78E-03 -1.31E-04 S13 -4.55E-01 -1.36E-03 -4.95E-04 2.42E-04 -5.58E-04 1.03E-04

[0142] In this embodiment, the field curvature curve, F-θ distortion curve, MTF curve, axial aberration curve, transverse chromatic aberration curve, and relative illumination curve of the optical lens 200 are respectively as follows: Figure 10 , Figure 11 , Figure 12 , Figure 13 , Figure 14 , Figure 15 and Figure 16 As shown. From Figure 10 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within -0.05mm to 0.03mm, indicating that the optical lens 200 can effectively correct field curvature. Figure 11 As can be seen, the F-θ distortion of the 200mm optical lens is controlled within 0-15%, and the image compression in the edge angle region is relatively smooth, effectively improving the sharpness of the unfolded image. From Figure 12 As can be seen, in this embodiment, the MTF value is above 0.3 across the entire field of view at an operating temperature of 20℃. Within the range of 0–160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, demonstrating good imaging quality and detail resolution even at room temperature. Figure 13As can be seen, in this embodiment, the MTF value is above 0.3 across the entire field of view at an operating temperature of -40℃. Within the range of 0–160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, demonstrating good imaging quality and detail resolution even at low temperatures. Figure 14 As can be seen, in this embodiment, the MTF value at an operating temperature of 85℃ is above 0.2 across the entire field of view. Within the range of 0–160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, demonstrating good imaging quality and detail resolution even at higher temperatures. Figure 15 As can be seen, the axial aberration offset in this embodiment is controlled within -0.03mm to 0.01mm, indicating that the optical lens can effectively correct axial aberration. From Figure 16 As can be seen, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within -1μm to 6μm, indicating that the optical lens can correct the chromatic aberration at the edge of the field of view and the secondary spectrum of the entire image plane very well.

[0143] Example 3

[0144] Please see Figure 17 The figure shown is a schematic diagram of the structure of the optical lens 300 provided in Embodiment 3 of the present invention. The main difference between this embodiment and Embodiment 1 is that the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0145] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0146] Table 3-1

[0147]

[0148]

[0149] The surface profile parameters of the aspherical lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0150] Table 3-2

[0151] Face number K B C D E F S3 1.47E+02 1.61E-02 -5.11E-03 7.44E-04 -5.69E-05 1.87E-06 S4 -5.89E-01 2.80E-02 1.98E-02 -1.52E-02 3.87E-03 -6.08E-04 S5 8.34E+00 -3.86E-05 5.41E-03 -4.77E-03 1.88E-03 -3.21E-04 S6 1.43E+01 4.38E-03 -1.88E-03 5.01E-03 -3.43E-03 9.38E-04 S12 -7.71E-01 -3.66E-02 1.21E-02 -6.42E-03 1.79E-03 -1.58E-04 S13 -6.22E-01 -3.36E-03 -3.08E-03 2.94E-03 -1.24E-03 1.80E-04

[0152] In this embodiment, the field curvature curve, F-θ distortion curve, MTF curve, axial aberration curve, transverse chromatic aberration curve, and relative illumination curve of the optical lens 300 at operating temperatures of 20°C, -40°C, and 85°C are respectively as follows: Figure 18 , Figure 19 , Figure 20 , Figure 21 , Figure 22, Figure 23 and Figure 24 As shown. From Figure 18 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within -0.05mm to 0.04mm, indicating that the optical lens 300 can effectively correct field curvature. From Figure 19 As can be seen, the F-θ distortion of the 300mm optical lens is controlled within 0-15%, and the image compression in the edge angle area is relatively smooth, effectively improving the sharpness of the unfolded image. From Figure 20 As can be seen, in this embodiment, the MTF value is above 0.35 across the entire field of view at an operating temperature of 20℃. Within the range of 0–160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, demonstrating good imaging quality and detail resolution even at room temperature. Figure 21 As can be seen, in this embodiment, the MTF value is above 0.3 across the entire field of view at an operating temperature of -40℃. Within the range of 0–160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, demonstrating good imaging quality and detail resolution even at low temperatures. Figure 22 As can be seen, in this embodiment, the MTF value at an operating temperature of 85℃ is above 0.2 across the entire field of view. Within the range of 0–160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, demonstrating good imaging quality and detail resolution even at higher temperatures. Figure 23 As can be seen, the axial aberration offset in this embodiment is controlled within -0.04mm to 0.01mm, indicating that the optical lens can effectively correct axial aberration. Figure 24 As can be seen, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within 0 to 5 μm, indicating that the optical lens can effectively correct chromatic aberration at the edge of the field of view and the secondary spectrum of the entire image plane.

[0153] Example 4

[0154] Please see Figure 25 The figure shown is a schematic diagram of the structure of the optical lens 400 provided in Embodiment 4 of the present invention. The main difference between this embodiment and Embodiment 1 is that the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0155] The relevant parameters of each lens in the optical lens 400 in Example 4 are shown in Table 4-1.

[0156] Table 4-1

[0157]

[0158] The surface profile parameters of the aspherical lens of the optical lens 400 in Example 4 are shown in Table 4-2.

[0159] Table 4-2

[0160] Face number K B C D E F S3 1.48E+02 1.06E-02 -2.19E-03 2.67E-04 -2.43E-05 1.18E-06 S4 -4.46E-01 3.50E-03 2.21E-02 -1.81E-02 8.97E-03 -2.00E-03 S5 2.03E+01 -2.53E-03 1.08E-03 -1.10E-03 9.11E-04 -3.07E-04 S6 1.38E+00 -4.19E-03 5.95E-05 1.34E-03 -1.47E-03 3.89E-04 S12 1.63E+00 -3.23E-02 5.68E-03 -1.73E-03 7.78E-04 -7.74E-05 S13 -8.61E-01 6.51E-03 -1.06E-02 7.30E-03 -2.47E-03 3.83E-04

[0161] In this embodiment, the field curvature curve, F-θ distortion curve, MTF curve, axial aberration curve, transverse chromatic aberration curve, and relative illumination curve of the optical lens 400 are respectively as follows: Figure 26 , Figure 27 , Figure 28 , Figure 29 , Figure 30 , Figure 31 and Figure 32 As shown. From Figure 26 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within -0.05mm to 0.05mm, indicating that the optical lens 400 can effectively correct field curvature. From Figure 27 As can be seen, the F-θ distortion of the 400mm optical lens is controlled within 0-15%, and the image compression in the edge angle region is relatively smooth, effectively improving the sharpness of the unfolded image. From Figure 28 As can be seen, in this embodiment, the MTF value is above 0.35 across the entire field of view at an operating temperature of 20℃. Within the range of 0–160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, demonstrating good imaging quality and detail resolution even at room temperature. Figure 29 As can be seen, in this embodiment, the MTF value is above 0.35 across the entire field of view at an operating temperature of -40℃. Within the range of 0–160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, demonstrating good imaging quality and detail resolution even at low temperatures. Figure 30 As can be seen, in this embodiment, the MTF value at an operating temperature of 85℃ is above 0.2 across the entire field of view. Within the range of 0–160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, demonstrating good imaging quality and detail resolution even at higher temperatures. Figure 31 As can be seen, the axial aberration offset in this embodiment is controlled within -0.01mm to 0.01mm, indicating that the optical lens can effectively correct axial aberration. Figure 2 As can be seen, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within -4μm to 3μm, indicating that the optical lens can correct the chromatic aberration at the edge of the field of view and the secondary spectrum of the entire image plane very well.

[0162] Please refer to Table 5 for the optical characteristics corresponding to each of the above embodiments, including the effective focal length f, total optical length TTL, aperture value Fno, true image height IH corresponding to the maximum field of view, maximum field of view FOV, and the values ​​corresponding to each conditional expression in each embodiment.

[0163] Table 5

[0164]

[0165]

[0166] In summary, the optical lens provided by the present invention employs seven lenses with specific optical power. Through specific surface shape matching and reasonable optical power distribution, it can improve the imaging quality of the optical lens, reduce aberrations, and enhance the imaging quality of the optical lens, giving the lens one or more advantages such as large aperture, large field of view, and high imaging quality.

[0167] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0168] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. An optical lens comprising seven lenses, characterized in that, It sequentially includes from the object side to the imaging surface along the optical axis: A first lens with a negative optical power, whose object side is convex and whose image side is concave; A second lens with a negative optical power, whose object side and image side are both concave; A third lens with a positive optical power, whose object side and image side are both convex; A fourth lens with a positive optical power, whose object side is convex and whose image side is concave; A fifth lens with a positive optical power, whose object side and image side are both convex; A sixth lens with a negative optical power, whose object side and image side are both concave; A seventh lens with a positive optical power, whose object side and image side are both convex; Wherein, the radius of curvature R12 of the image side of the sixth lens and the radius of curvature R14 of the image side of the seventh lens satisfy: 0 < (R12 + R14) / (R12 - R14) < 1; the radius of curvature R8 of the image side of the fourth lens and the effective focal length f of the optical lens satisfy: 3 < R8 / f ≤ 253.45; The combined focal length f1234 of the first lens, the second lens, the third lens and the fourth lens and the combined focal length f567 of the fifth lens, the sixth lens and the seventh lens satisfy: 0.4 < f1234 / f567 < 1.

2.

2. The optical lens according to claim 1, characterized in that, The maximum field angle FOV of the optical lens and the aperture value FNO of the optical lens satisfy: 110° < FOV / FNO ≤ 116.67°.

3. The optical lens according to claim 1, characterized in that, The true image height IH corresponding to the maximum field angle of the optical lens and the effective focal length f of the optical lens satisfy: 3.5 < IH / f < 4.

7.

4. The optical lens according to claim 1, characterized in that, The focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: 7 < f4 / f < 16.

5. The optical lens according to claim 1, characterized in that, The radius of curvature R9 of the object side of the fifth lens and the effective focal length f of the optical lens satisfy: 3 < R9 / f < 12.

6. The optical lens according to claim 1, characterized in that, The radius of curvature R13 of the object side of the seventh lens and the effective focal length f of the optical lens satisfy: 3 < R13 / f < 5.

7. The optical lens according to claim 1, characterized in that, The radius of curvature R7 of the object side of the fourth lens and the radius of curvature R8 of the image side of the fourth lens satisfy: -1 < (R7 - R8) / (R7 + R8) < 0.

8. The optical lens according to claim 1, characterized in that, The radius of curvature R12 of the image side of the sixth lens and the radius of curvature R14 of the image side of the seventh lens satisfy: 0.45 ≤ (R12 + R14) / (R12 - R14) ≤ 0.65; the radius of curvature R8 of the image side of the fourth lens and the effective focal length f of the optical lens satisfy: 9.03 ≤ R8 / f ≤ 253.45; The combined focal length f1234 of the first lens, the second lens, the third lens and the fourth lens and the combined focal length f567 of the fifth lens, the sixth lens and the seventh lens satisfy: 0.61 ≤ f1234 / f567 ≤ 1.

01.

9. The optical lens according to claim 1, characterized in that, The sagittal height Sag8 of the clear aperture radius of the image side of the fourth lens satisfies: 0 < Sag8 < 0.2 mm; the sagittal height Sag12 of the clear aperture radius of the image side of the sixth lens satisfies: 0 < Sag12 < 0.3 mm.

10. The optical lens according to claim 1, characterized in that, The distance CT23 between the second lens and the third lens on the optical axis, the distance CT34 between the third lens and the fourth lens on the optical axis, and the center thickness CT4 of the fourth lens satisfy: 1.5 <CT23 / (CT34+CT4)<3.5。

Images