Optical lens

Abstract

The application provides an optical lens, which has nine lenses with optical power, and sequentially comprises, along an optical axis from an object side to an imaging surface, a first lens with negative optical power, whose object side surface is a convex surface and whose image side surface is a concave surface; a second lens with negative optical power, whose object side surface is a concave surface and whose image side surface is a convex surface; a third lens with positive optical power, whose object side surface is a convex surface and whose image side surface is a convex surface; a fourth lens with optical power, whose object side surface is a concave surface and whose image side surface is a convex surface; a fifth lens with positive optical power, whose object side surface is a convex surface and whose image side surface is a convex surface; a sixth lens with negative optical power, whose image side surface is a concave surface; a seventh lens with positive optical power, whose object side surface is a convex surface and whose image side surface is a convex surface; an eighth lens with optical power; and a ninth lens with negative optical power. The optical lens provided by the application can improve the imaging quality of the optical lens, reduce aberration and improve the imaging quality of the optical lens.

Description

Technical Field

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

[0002] In the field of modern motion capture, high-performance portable optical systems are a core requirement. Currently, most action camera lenses on the market employ large-aperture, ultra-wide-angle designs to adapt to high-speed motion scenes and extreme environments. However, these traditional optical structures generally suffer from reduced image quality in low-light conditions and insufficient dynamic range. Simultaneously, the increased field of view makes aberration correction difficult, further degrading image quality; and existing lenses have relatively small imaging surfaces, making it difficult to meet market demands. Summary of the Invention

[0003] To address the aforementioned problems, the present invention aims to provide an optical lens with the advantage of excellent image quality.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0005] An optical lens has nine lenses with optical power, arranged sequentially along the optical axis from the object side to the imaging plane:

[0006] The first lens with negative optical power has a convex object side and a concave image side.

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

[0008] A third lens with positive optical power has a convex object-side surface and a convex image-side surface.

[0009] The fourth lens with optical power has a concave object side and a convex image side.

[0010] The fifth lens with positive optical power has a convex object-side surface and a convex image-side surface.

[0011] The sixth lens has negative optical power and its image-side surface is concave.

[0012] The seventh lens with positive optical power has a convex object-side surface and a convex image-side surface.

[0013] The eighth lens, which has optical power, has a convex image-side surface;

[0014] The ninth lens, which has negative optical power, has a concave image-side surface.

[0015] The true image height IH corresponding to the maximum field of view of the optical lens and the effective focal length f of the optical lens satisfy: 2.6 <IH / f<3.2。

[0016] More preferably, the optical lens satisfies one or more of the following conditional expressions: the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 5 < TTL / f < 6.5; the total optical length TTL of the optical lens and the true image height IH corresponding to the maximum field angle of the optical lens satisfy: 1.7 < TTL / IH < 2.1.

[0017] More preferably, the optical lens satisfies one or more of the following conditional expressions: the maximum field angle FOV of the optical lens and the f-number Fno of the optical lens satisfy: 65° < FOV / Fno < 75°; the true image height IH corresponding to the maximum field angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 6.5 < IH / EPD < 8.

[0018] More preferably, the optical lens satisfies one or more of the following conditional expressions: the total optical length TTL of the optical 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: 7 < 180° × TTL / (IH / 2) / (FOV / 2) < 8.5; the effective focal length f of the optical 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: 55° < f × FOV / IH < 65°.

[0019] More preferably, the optical lens satisfies one or more of the following conditional expressions: 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: 2.83 < IH / f < 3; the half clear aperture d1 of the object side 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: 0.03 < d1 / (IH / 2) / tan(FOV / 2) < 0.06; the true image height IH corresponding to the maximum field angle of the optical lens, the effective focal length f of the optical lens, and the radian value θ of the maximum half field angle of the optical lens satisfy: 0.9 < (IH / 2) / (f × θ) < 0.1.

[0020] Further preferably, the optical lens satisfies one or more of the following conditional expressions: The focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: -2.1 < f1 / f < -1.3; The focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: -3.7 < f2 / f < -2; The focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 1.4 < f3 / f < 2.3; The focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: 11 < |f4 / f| < 37; The focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy: 1.4 < f5 / f < 1.9; The focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: -1.4 < f6 / f < -1; The focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: 1.1 < f7 / f < 1.7; The focal length f8 of the eighth lens and the effective focal length f of the optical lens satisfy: 4 < |f8 / f| < 360; The focal length f9 of the ninth lens and the effective focal length f of the optical lens satisfy: -16 < f9 / f < -7.2.

[0021] Further preferably, an aperture is provided between the fourth lens and the fifth lens; The optical lens satisfies one or more of the following conditional expressions: The combined focal length fb of the lenses behind the aperture and the effective focal length f of the optical lens satisfy: 1.5 < fb / f < 2.2; The focal length f5 of the fifth lens, the focal length f6 of the sixth lens, the focal length f7 of the seventh lens, the focal length f8 of the eighth lens, the focal length f9 of the ninth lens and the combined focal length fb of the lenses behind the aperture satisfy: -230 < (f5 + f6 + f7 + f8 + f9) / fb < -4.4.

[0022] Further preferably, the sixth lens and the seventh lens form a cemented lens group with optical power; The optical lens satisfies one or more of the following conditional expressions: The combined focal length fjiao1 of the sixth lens and the seventh lens and the effective focal length f of the optical lens satisfy: 12 < |fjiao1 / f| < 150; The focal length f6 of the sixth lens and the focal length f7 of the seventh lens satisfy: -1.1 < f6 / f7 < -0.65; The combined focal length fjiao1 of the sixth lens and the seventh lens, the focal length f6 of the sixth lens and the focal length f7 of the seventh lens satisfy: -3300 < fjiao1 / (f6 + f7) < -25.

[0023] Further preferably, the optical lens satisfies one or more of the following conditional expressions: among all the lenses with positive optical power, the lens with the smallest focal length f_pos_min and among all the lenses with negative optical power, the lens with the largest focal length f_neg_max satisfy: -1.5 < f_pos_min / f_neg_max < -0.9; the focal length f1 of the first lens and the largest focal length f_neg_max among all the lenses with negative optical power satisfy: 1.2 < f1 / f_neg_max < 1.7; the focal length f9 of the ninth lens and the smallest focal length f_pos_min among all the lenses with positive optical power satisfy: -10.5 < f9 / f_pos_min < -6.

[0024] Further preferably, the optical lens satisfies one or more of the following conditional expressions: the focal length f1 of the first lens and the focal length f9 of the ninth lens satisfy: 0.05 < f1 / f9 < 0.3; the focal length f4 of the fourth lens and the focal length f5 of the fifth lens satisfy: 6.5 < |f4 / f5| < 25.

[0025] The optical lens provided by the present invention adopts nine lenses with specific optical powers. Through specific surface shape matching and reasonable optical power distribution, it can improve the imaging quality of the optical lens, reduce aberration, improve the imaging quality of the optical lens, and enable the lens to have one or more advantages such as miniaturization, large viewing angle, large image plane, high pixel, and high imaging quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The above and / or additional aspects and advantages of the present invention will become obvious and easy to understand from the description of the embodiments in conjunction with the following drawings, where:

[0027] Figure 1 is a schematic structural diagram of the optical lens in Embodiment 1 of the present invention.

[0028] Figure 2 is an F-Theta distortion curve diagram of the optical lens in Embodiment 1 of the present invention.

[0029] Figure 3 is an axial aberration curve diagram of the optical lens in Embodiment 1 of the present invention.

[0030] Figure 4 is an MTF curve diagram of the optical lens in Embodiment 1 of the present invention.

[0031] Figure 5 is a schematic structural diagram of the optical lens in Embodiment 2 of the present invention.

[0032] Figure 6 is an F-Theta distortion curve diagram of the optical lens in Embodiment 2 of the present invention.

[0033] Figure 7This is an axial aberration curve of the optical lens in Embodiment 2 of the present invention.

[0034] Figure 8 This is the MTF curve of the optical lens in Embodiment 2 of the present invention.

[0035] Figure 9 This is a schematic diagram of the optical lens in Embodiment 3 of the present invention.

[0036] Figure 10 This is the F-Theta distortion curve of the optical lens in Embodiment 3 of the present invention.

[0037] Figure 11 This is an axial aberration curve of the optical lens in Embodiment 3 of the present invention.

[0038] Figure 12 This is an MTF curve of the optical lens in Embodiment 3 of the present invention.

[0039] The following detailed description, in conjunction with the accompanying drawings, will further illustrate the present invention. Detailed Implementation

[0040] 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.

[0041] 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.

[0042] 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.

[0043] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the location of the convexity is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the location of the concaveness 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 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.

[0044] 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.

[0045] 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.

[0046] 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.

[0047] The optical lens of this invention has nine lenses with optical power, arranged sequentially along the optical axis from the object side to the imaging plane: first lens, second lens, third lens, fourth lens, fifth lens, sixth lens, seventh lens, eighth lens, and ninth lens.

[0048] In some embodiments, the first lens may have negative optical power, with a convex object-side surface and a concave image-side surface. The second lens may have negative optical power, with a concave object-side surface and a convex image-side surface. The third lens may have positive optical power, with a convex object-side surface and a convex image-side surface. The fourth lens may have either positive or negative optical power, with a concave object-side surface and a convex image-side surface. The fifth lens may have positive optical power, with a convex object-side surface and a convex image-side surface. The sixth lens may have negative optical power, with either a concave or convex object-side surface and a concave image-side surface. The seventh lens may have positive optical power, with both a convex object-side surface and a convex image-side surface. The eighth lens may have either positive or negative optical power, with either a concave or convex object-side surface and a convex image-side surface. The ninth lens may have negative optical power, with either a concave or convex object-side surface and a concave image-side surface.

[0049] 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 is used to limit the amount of light entering the lens, thereby altering the brightness of the image.

[0050] In some embodiments, the optical lens may further include a filter, which is disposed between the ninth lens and the imaging surface. The filter is used to filter out interfering light and prevent the interfering light from reaching the imaging surface of the optical lens and affecting normal imaging.

[0051] In some embodiments, the sixth lens and the seventh lens may be glued together to form a glued lens group with optical power, which can effectively correct the chromatic aberration of the optical lens, reduce the eccentricity sensitivity of the optical lens, balance the aberration 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 f_glue1 of the sixth lens and the seventh lens and the effective focal length f of the optical lens satisfy: 12 < |f_glue1 / f| < 150. More specifically, 12.35 < |f_glue1 / f| < 143.8.

[0052] 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: 2.6 < IH / f < 3.2. Satisfying the above range and controlling the image height and focal length of the optical lens within a reasonable range helps the optical lens to have the characteristic of a large image surface and improve the imaging quality. More specifically, 2.83 < IH / f < 3.

[0053] In some embodiments, the overall optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 5 < TTL / f < 6.5. Satisfying the above range can effectively limit the length of the lens and is beneficial to the miniaturization of the optical lens. More specifically, 5.12 < TTL / f < 5.97.

[0054] In some embodiments, the overall optical length TTL of the optical lens and the true image height IH corresponding to the maximum field angle of the optical lens satisfy: 1.7 < TTL / IH < 2.1. Satisfying the above range ensures that the lens has a larger image surface under the same overall length, can match a larger-sized imaging chip to achieve high-definition imaging, and better realizes the balance between the small overall length and the large image surface of the lens. More specifically, 1.79 < TTL / IH < 2.01.

[0055] In some embodiments, the maximum field angle FOV of the optical lens and the f-number Fno of the optical lens satisfy: 65° < FOV / Fno < 75°. Satisfying the above range defines that the optical lens has a suitable field angle and f-number, can collect light at a large angle and obtain good imaging quality. More specifically, 70.3° < FOV / Fno < 70.5°.

[0056] In some embodiments, the true image height IH corresponding to the maximum field angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 6.5 < IH / EPD < 8. Meeting the above range can increase the width of the light beam entering the optical lens, improve the brightness at the image plane of the optical lens, and avoid vignetting. More specifically, 7.08 < IH / EPD < 7.47.

[0057] In some embodiments, the total optical length TTL of the optical 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: 7 < 180°×TTL / (IH / 2) / (FOV / 2) < 8.5. Meeting the above range can achieve a balance among the image height, focal length, and total optical length, and improve the imaging quality of the optical lens. More specifically, 7.35 < 180°×TTL / (IH / 2) / (FOV / 2) < 8.18.

[0058] In some embodiments, the effective focal length f of the optical 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: 55° < f×FOV / IH < 65°. Meeting the above conditional formula is conducive to achieving the balance between the field angle of the optical lens and large target plane imaging by reasonably restricting the relationship among the focal length, field angle, and image height of the optical lens, and better meeting the usage requirements of high image quality shooting of the optical lens. More specifically, 58.94° < f×FOV / IH < 62.08°.

[0059] In some embodiments, the half-aperture 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: 0.03 < d1 / (IH / 2) / tan(FOV / 2) < 0.06. Meeting the above range can ensure the balance among the size of the optical lens, the field angle, and the image plane.

[0060] In some embodiments, the true image height IH corresponding to the maximum field angle of the optical lens, the effective focal length f of the optical lens, and the radian value θ of the maximum half-field angle of the optical lens satisfy: 0.9 < (IH / 2) / (f×θ) < 0.1. Meeting the above range can make the lens have a small distortion value and provide a high-definition imaging effect. More specifically, 0.91 < (IH / 2) / (f×θ) < 0.98.

[0061] In some embodiments, the focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: -2.1 < f1 / f < -1.3. Meeting the above range, the first lens has an appropriate negative focal length, which is conducive to expanding the field angle of the optical lens. More specifically, -2.02 < f1 / f < -1.45.

[0062] In some embodiments, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: -3.7 < f2 / f < -2. When within the above range, and the second lens also being a negative lens, it can further diverge light and increase the field angle of the imaging system. More specifically, -3.48 < f2 / f < -2.14.

[0063] In some embodiments, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 1.4 < f3 / f < 2.3. When within the above range, the third lens appropriately converges the incident light at the front end, which is beneficial for correcting the aberrations and the distortion of the edge field brought by the first lens and the second lens, enabling the lens to have less distortion and providing a high-definition imaging effect. More specifically, 1.47 < f3 / f < 2.14.

[0064] In some embodiments, the focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: 11 < |f4 / f| < 37. When within the above range, various aberrations of the optical lens can be fully corrected, the resolution can be improved, and high resolution can be achieved. More specifically, 11.62 < |f4 / f| < 36.66.

[0065] In some embodiments, the focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy: 1.4 < f5 / f < 1.9. When within the above range, it is beneficial for the smooth transition of light, facilitating the correction of astigmatism and field curvature, improving the imaging quality of the optical lens, and ensuring the stability of the optical system. More specifically, 1.52 < f5 / f < 1.77.

[0066] In some embodiments, the focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: -1.4 < f6 / f < -1; the focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: 1.1 < f7 / f < 1.7. When within the above range, the cooperation of the sixth lens with negative optical power and the seventh lens with positive optical power can adjust the optical path difference between different fields, improve the resolution, be beneficial for the light to enter the rear lens smoothly, further reduce the field curvature, and correct the off-axis point aberrations of the optical lens. More specifically, -1.29 < f6 / f < -1.03; 1.19 < f7 / f < 1.6.

[0067] In some embodiments, the focal length f8 of the eighth lens and the effective focal length f of the optical lens satisfy: 4 < |f8 / f| < 360. When within the above range, various aberrations of the optical lens can be fully corrected, the resolution can be improved, and high resolution can be achieved. More specifically, 4.34 < |f8 / f| < 351.6.

[0068] In some embodiments, the focal length f9 of the ninth lens and the effective focal length f of the optical lens satisfy: -16 < f9 / f < -7.2. By setting the ninth lens to have a negative optical power, the incident light can be diverged to a large extent, causing the peripheral light and the central light to turn upward, reaching a higher imaging position, better achieving large-format imaging of the lens, and improving the imaging quality. More specifically, -15.82 < f9 / f < -7.81.

[0069] In some embodiments, the combined focal length fb of the lenses behind the aperture and the effective focal length f of the optical lens satisfy: 1.5 < fb / f < 2.2; the focal length f5 of the fifth lens, the focal length f6 of the sixth lens, the focal length f7 of the seventh lens, the focal length f8 of the eighth lens, the focal length f9 of the ninth lens and the combined focal length fb of the lenses behind the aperture satisfy: -230 < (f5 + f6 + f7 + f8 + f9) / fb < -4.4. Satisfying the above ranges, by reasonably setting the focal lengths of the lens group behind the aperture, it is beneficial to balance various aberrations generated by the lens group in front of the aperture and improve the overall imaging quality. More specifically, 1.58 < fb / f < 2.06; -224.52 < (f5 + f6 + f7 + f8 + f9) / fb < -4.82.

[0070] In some embodiments, the focal length f6 of the sixth lens and the focal length f7 of the seventh lens satisfy: -1.1 < f6 / f7 < -0.65; the combined focal length fglue1 of the sixth lens and the seventh lens, the focal length f6 of the sixth lens and the focal length f7 of the seventh lens satisfy: -3300 < fglue1 / (f6 + f7) < -25. Satisfying the above ranges is beneficial to the smooth transition of light, improves the imaging quality of the optical lens, and ensures the stability of the optical system. More specifically, -1.05 < f6 / f7 < -0.7; -3247.19 < fglue1 / (f6 + f7) < -26.8.

[0071] In some embodiments, the minimum focal length f_pos_min among all the lenses with positive optical power and the maximum focal length f_neg_max among all the lenses with negative optical power satisfy: -1.5 < f_pos_min / f_neg_max < -0.9; the focal length f1 of the first lens and the maximum focal length f_neg_max among all the lenses with negative optical power satisfy: 1.2 < f1 / f_neg_max < 1.7; the focal length f9 of the ninth lens and the minimum focal length f_pos_min among all the lenses with positive optical power satisfy: -10.5 < f9 / f_pos_min < -6. It can be understood that f_pos_min is the smallest in value among all the lenses with positive optical power and has the greatest influence on the deflection of light rays; f_neg_max is the largest in value among all the lenses with negative optical power and has the greatest influence on the deflection of light rays. Meeting the above ranges makes the influence on the degree of light ray deflection close, which is beneficial to balancing the aberration of the optical lens. More specifically, -1.42 < f_pos_min / f_neg_max < -0.96; 1.28 < f1 / f_neg_max < 1.58; -9.95 < f9 / f_pos_min < -6.32.

[0072] In some embodiments, the focal length f1 of the first lens and the focal length f9 of the ninth lens satisfy: 0.05 < f1 / f9 < 0.3. Meeting the above range, by reasonably setting the focal length relationship between the first and last lenses in the lens, while ensuring that as many light rays as possible enter the system, the area of the light rays entering the imaging surface is increased, which is beneficial to achieving large image surface imaging of the lens, while increasing the light input and improving the relative illuminance of the system. More specifically, 0.08 < f1 / f9 < 0.27.

[0073] In some embodiments, the focal length f4 of the fourth lens and the focal length f5 of the fifth lens satisfy: 6.5 < |f4 / f5| < 25. Meeting the above range, by reasonably setting the focal length relationship between the lenses before and after the aperture, the excessive deflection of light rays can be avoided, and the difficulty of aberration correction can be reduced. More specifically, 7 < |f4 / f5| < 23.96.

[0074] In some embodiments, the curvature radius R1 of the object side of the first lens and the curvature radius R2 of the image side of the first lens satisfy: 0.5 < (R1 - R2) / (R1 + R2) < 0.7; the curvature radius R3 of the object side of the second lens and the curvature radius R4 of the image side of the second lens satisfy: -0.6 < (R3 - R4) / (R3 + R4) < -0.3. The first lens and the second lens are both meniscus negative lenses, which collect as many light rays with large field angles as possible and make the light rays enter the subsequent system smoothly, increasing the light throughput of the optical lens and effectively expanding the field of view range of the optical lens. More specifically, 0.5 < (R1 - R2) / (R1 + R2) < 0.64; -0.59 < (R3 - R4) / (R3 + R4) < -0.31.

[0075] In some embodiments, the object-side radius of curvature R5 of the third lens and the image-side radius of curvature R6 of the third lens satisfy the following condition: 1.4 < (R5 - R6) / (R5 + R6) < 5.8. Meeting this range helps correct aberrations and distortions at the edges of the field of view introduced by the first and second lenses, resulting in a lens with less distortion and providing high-definition imaging. More specifically, 1.48 < (R5 - R6) / (R5 + R6) < 5.4.

[0076] In some embodiments, the object-side radius of curvature R7 of the fourth lens and the image-side radius of curvature R8 of the fourth lens satisfy: 0 < |(R7-R8) / (R7+R8)| < 0.2. Satisfying this range can balance various aberrations generated by the optical lens and improve the imaging quality of the optical lens. More specifically, -0.2 < (R7-R8) / (R7+R8) < 0.02.

[0077] In some embodiments, the object-side radius of curvature R9 of the fifth lens and the image-side radius of curvature R10 of the fifth lens satisfy: -0.6 < (R9 + R10) / (R9 - R10) < 0.2. Meeting this range allows the fifth lens to be a biconvex type, which can balance various aberrations generated by the optical lens and improve the imaging quality of the optical lens. More specifically, -0.51 < (R9 + R10) / (R9 - R10) < 0.19.

[0078] In some embodiments, the object-side radius of curvature R13 of the seventh lens and the image-side radius of curvature R14 of the seventh lens satisfy: -1 < (R13 + R14) / (R13 - R14) < -0.1. Meeting this range is beneficial for converging light while correcting field curvature and distortion of the optical lens, thereby improving the imaging quality of the optical lens. More specifically, -0.96 < (R13 + R14) / (R13 - R14) < 0.1.

[0079] In some embodiments, the optical lens satisfies the following conditional expressions: 5 mm < f < 6 mm; 2 mm < EPD < 2.4 mm; 29 mm < TTL < 32 mm; 2.3 < Fno < 2.8; 11° < CRA < 35°; 4 mm < BFL < 5.5 mm; 170° < FOV < 180°; 15 mm < IH < 17 mm. In the above conditional expressions, f represents the effective focal length of the optical lens, EPD represents the entrance pupil diameter of the optical lens, TTL represents the overall optical length of the optical lens, Fno represents the aperture value of the optical lens, CRA represents the principal ray incident angle at the maximum image height of the optical lens, BFL represents the back focal length of the optical lens, FOV represents the maximum field angle of the optical lens, and IH represents the true image height corresponding to the maximum field angle of the optical lens. Meeting the above ranges, the optical lens has at least one or more advantages such as miniaturization, large image plane, large aperture, and large field angle. More specifically, 5.22 mm < f < 5.74 mm; 2.08 mm < EPD < 2.3 mm; 29.35 mm < TTL < 31.22 mm; 2.45 < Fno < 2.55; 11.86° < CRA < 34.86°; 4.41 mm < BFL < 5.16 mm; 175° < FOV < 177°; 15.62 mm < IH < 16.32 mm.

[0080] In some embodiments, the lens material of the optical lens provided by the present invention can be glass or plastic. When the lens material is plastic, the production cost can be effectively reduced. When the lens material is glass, the geometric chromatic aberration of the optical system can be effectively corrected by the low dispersion characteristic of the glass itself. The optical lens provided by the present invention can adopt an all-glass lens structure, which can reduce dispersion, effectively correct the chromatic aberration of the optical lens, and improve the imaging quality.

[0081] 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 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 second lens, the fifth lens, and the ninth lens of the present invention adopt aspherical lenses; the eighth lens adopts an aspherical lens or a spherical lens; the first lens, the third lens, the fourth lens, the sixth lens, and the seventh lens adopt spherical lenses.

[0082] 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 equations:

[0083] ;

[0084] Where z is the distance between the surface and the vertex of the surface in the direction of the optical axis, h is the distance from the optical axis to the surface, c is the curvature of the vertex of the surface, K is the quadratic surface coefficient, and B, C, D, E, and F are the fourth, sixth, eighth, tenth, and twelfth order surface coefficients, respectively.

[0085] 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.

[0086] Example 1

[0087] Please see Figure 1 The diagram shown is a structural schematic of the optical lens 100 provided in Embodiment 1 of the present invention. The optical lens 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, an eighth lens L8, a ninth lens L9, and a filter G1.

[0088] Among them, the first lens L1 has negative optical power, its object side S1 is convex, and its image side S2 is concave.

[0089] The second lens L2 has negative optical power, its object side S3 is concave, and its image side S4 is convex.

[0090] The third lens L3 has positive optical power, its object side S5 is convex, and its image side S6 is convex.

[0091] The fourth lens L4 has positive optical power, its object side S7 is concave, and its image side S8 is convex.

[0092] The fifth lens L5 has positive optical power, its object side S9 is convex, and its image side S10 is convex.

[0093] The sixth lens L6 has negative optical power, its object-side surface S11 is concave, and its image-side surface is concave.

[0094] The seventh lens L7 has positive optical power, its object side is convex, and its image side S13 is convex.

[0095] The sixth lens L6 and the seventh lens L7 form a cemented lens group with negative optical power, that is, the cemented surface of the image side of the sixth lens L6 and the object side of the seventh lens L7 is S12.

[0096] The eighth lens L8 has positive optical power, its object side S14 is convex, and its image side S15 is convex.

[0097] The ninth lens L9 has negative optical power, its object side S16 is convex, and its image side S17 is concave.

[0098] The object-side surface S18 and the image-side surface S19 of filter G1 are both planar.

[0099] The imaging plane S20 is a plane.

[0100] The first, third, fourth, sixth, seventh, and eighth lenses are glass spherical lenses, while the second, fifth, and ninth lenses are glass aspherical lenses.

[0101] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0102] Table 1-1

[0103]

[0104] The surface profile parameters of the aspherical lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0105] Table 1-2

[0106]

[0107] In this embodiment, the F-Theta distortion curve, axial aberration curve, and MTF curve of the optical lens 100 are respectively as follows: Figure 2 , Figure 3 , Figure 4 As shown.

[0108] Figure 2 The F-Theta distortion curve of Example 1 is shown, which represents the F-Theta distortion of light at different image heights on the imaging plane. The horizontal axis represents the F-Theta distortion value (unit: %), and the vertical axis represents the half field of view (unit: °). As can be seen from the figure, the F-Theta distortion of the optical lens is controlled within ±5%, indicating that the optical lens can correct distortion well.

[0109] Figure 3 The axial aberration curve of Example 1 is shown, which represents the aberration of each wavelength on 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. As can be seen from the figure, the axial aberration offset is controlled within -0.02 mm to 0.04 mm, indicating that the optical lens can correct axial aberration well.

[0110] Figure 4The MTF (Modulation Transfer Function) curve of Example 1 is shown, which 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 MTF value. As can be seen from the figure, the MTF value of this example is above 0.4 throughout 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 imaging quality and good detail resolution at both low and high frequencies.

[0111] Example 2

[0112] Please see Figure 5 The diagram shows a schematic of the structure of the optical lens 200 provided in Embodiment 2 of the present invention. The optical lens in this embodiment is roughly the same as that in Embodiment 1, except that: the eighth lens L8 has negative optical power; the object side surface S11 of the sixth lens L6 is convex; the object side surface S14 of the eighth lens L8 is concave; the eighth lens is a glass aspherical lens; and the optical parameters such as the radius of curvature, aspherical coefficient, and thickness of each lens surface are different.

[0113] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0114] Table 2-1

[0115]

[0116] The surface profile parameters of the aspherical lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0117] Table 2-2

[0118]

[0119] In this embodiment, the F-Theta distortion curve, axial aberration curve, and MTF curve of the optical lens 200 are respectively as follows: Figure 6 , Figure 7 , Figure 8 As shown.

[0120] from Figure 6 As can be seen, the F-Theta distortion of the optical lens is controlled within -10% to 5%, indicating that the optical lens can correct distortion well.

[0121] from Figure 7 As can be seen, the axial aberration offset is controlled within ±0.02mm, indicating that the optical lens can effectively correct axial aberration.

[0122] from Figure 8As can be seen, the MTF value of this embodiment is above 0.38 throughout the entire field of view. In the range of 0 to 160 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view, and it has good imaging quality and good detail resolution in both low and high frequency conditions.

[0123] Example 3

[0124] Please see Figure 9 The diagram shows a schematic of the optical lens 300 provided in Embodiment 3 of the present invention. The optical lens in this embodiment is largely the same as that in Embodiment 1, with the main differences being: the fourth lens L4 has negative optical power; the eighth lens L8 has negative optical power; the sixth lens L6 and the seventh lens L7 form a cemented lens group with positive optical power; the object-side surface S11 of the sixth lens L6 is convex; the object-side surface S14 of the eighth lens L8 is concave; the object-side surface S16 of the ninth lens L9 is concave; the eighth lens is a glass aspherical lens; and the optical parameters such as the radius of curvature, aspherical coefficient, and thickness of each lens surface are different.

[0125] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0126] Table 3-1

[0127]

[0128] The surface profile parameters of the aspherical lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0129] Table 3-2

[0130]

[0131] In this embodiment, the F-Theta distortion curve, axial aberration curve, and MTF curve of the optical lens 300 are respectively as follows: Figure 10 , Figure 11 , Figure 12 As shown.

[0132] from Figure 10 As can be seen, the F-Theta distortion of the optical lens is controlled within -10% to 5%, indicating that the optical lens can correct distortion well.

[0133] from Figure 11 As can be seen, the axial aberration offset is controlled within ±0.02mm, indicating that the optical lens can effectively correct axial aberration.

[0134] from Figure 12As can be seen, the MTF value of this embodiment is above 0.48 throughout the entire field of view. In the range of 0 to 120 lp / mm, the MTF curve decreases smoothly and evenly from the center to the edge of the field of view. It has good imaging quality and good detail resolution in both low and high frequency conditions.

[0135] Please refer to Tables 4-1 and 4-2 for the optical characteristics corresponding to 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, principal ray incident angle CRA at the maximum image height, maximum field of view FOV, and the values ​​corresponding to each conditional expression in each embodiment.

[0136] Table 4-1

[0137]

[0138] Table 4-2

[0139]

[0140] In summary, the optical lens provided by the present invention employs nine 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 miniaturization, large field of view, large image plane, high pixel count, and high imaging quality.

[0141] 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.

[0142] 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 nine lenses having optical power, characterized in that, It successively 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 is concave and whose image side is convex; A third lens with a positive optical power, whose object side is convex and whose image side is convex; A fourth lens with an optical power, whose object side is concave and whose image side is convex; A fifth lens with a positive optical power, whose object side is convex and whose image side is convex; A sixth lens with a negative optical power, whose image side is concave; A seventh lens with a positive optical power, whose object side is convex and whose image side is convex; An eighth lens with an optical power, whose image side is convex; A ninth lens with a negative optical power, whose image side is concave; 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: 2.6 < IH / f < 3.2; The clear aperture radius d1 of the object side 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: 0.03 < d1 / (IH / 2) / tan(FOV / 2) < 0.06; An aperture stop is provided between the fourth lens and the fifth lens; The focal length f5 of the fifth lens, the focal length f6 of the sixth lens, the focal length f7 of the seventh lens, the focal length f8 of the eighth lens, the focal length f9 of the ninth lens and the combined focal length fb of the lenses behind the aperture stop satisfy: -230 < (f5 + f6 + f7 + f8 + f9) / fb < -4.

4.

2. The optical lens according to claim 1, characterized in that, The optical lens satisfies one or more of the following conditional expressions: The overall optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 5 < TTL / f < 6.5; The overall optical length TTL of the optical lens and the true image height IH corresponding to the maximum field angle of the optical lens satisfy: 1.7 < TTL / IH < 2.

1.

3. The optical lens according to claim 1, characterized in that, The optical lens satisfies one or more of the following conditional expressions: The maximum field angle FOV of the optical lens and the f-number Fno of the optical lens satisfy: 65° < FOV / Fno < 75°; The true image height IH corresponding to the maximum field angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 6.5 < IH / EPD < 8.

4. The optical lens according to claim 1, characterized in that, The optical lens satisfies one or more of the following conditional expressions: The overall optical length TTL of the optical 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: 7 < 180°×TTL / (IH / 2) / (FOV / 2) < 8.5; The effective focal length f of the optical 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: 55° < f×FOV / IH < 65°.

5. The optical lens according to claim 1, characterized in that, The optical lens satisfies one or more of the following conditional expressions: 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: 2.83 < IH / f < 3; The true image height IH corresponding to the maximum field angle of the optical lens, the effective focal length f of the optical lens, and the radian value θ of the maximum semi-field angle of the optical lens satisfy: 0.91 < (IH / 2) / (f×θ) < 0.

98.

6. The optical lens according to claim 1, characterized in that, The optical lens satisfies one or more of the following conditional expressions: The focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: -2.1 < f1 / f < -1.3; The focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: -3.7 < f2 / f < -2; The focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 1.4 < f3 / f < 2.3; The focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: 11 < |f4 / f| < 37; The focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy: 1.4 < f5 / f < 1.9; The focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: -1.4 < f6 / f < -1; The focal length f7 of the seventh lens and the effective focal length f of the optical lens satisfy: 1.1 < f7 / f < 1.7; The focal length f8 of the eighth lens and the effective focal length f of the optical lens satisfy: 4 < |f8 / f| < 360; The focal length f9 of the ninth lens and the effective focal length f of the optical lens satisfy: -16 < f9 / f < -7.

2.

7. The optical lens according to claim 1, characterized in that, The combined focal length fb of the lenses behind the aperture and the effective focal length f of the optical lens satisfy: 1.5 < fb / f < 2.

2.

8. The optical lens according to claim 1, characterized in that, The sixth lens and the seventh lens form a cemented lens group with a focal power; The optical lens satisfies one or more of the following conditional expressions: The combined focal length f_glue1 of the sixth lens and the seventh lens and the effective focal length f of the optical lens satisfy: 12 < |f_glue1 / f| < 150; The focal length f6 of the sixth lens and the focal length f7 of the seventh lens satisfy: -1.1 < f6 / f7 < -0.65; The combined focal length f_glue1 of the sixth lens and the seventh lens, the focal length f6 of the sixth lens, and the focal length f7 of the seventh lens satisfy: -3300 < f_glue1 / (f6 + f7) < -25.

9. The optical lens according to claim 1, characterized in that, The optical lens satisfies one or more of the following conditional expressions: The minimum focal length \(f_{positive\ min}\) among all lenses with positive optical power and the maximum focal length \(f_{negative\ max}\) among all lenses with negative optical power satisfy: \(-1.5 < f_{positive\ min} / f_{negative\ max}< -0.9\); The focal length \(f_1\) of the first lens and the maximum focal length \(f_{negative\ max}\) among all lenses with negative optical power satisfy: \(1.2 < f_1 / f_{negative\ max}< 1.7\); The focal length \(f_9\) of the ninth lens and the minimum focal length \(f_{positive\ min}\) among all lenses with positive optical power satisfy: \(-10.5 < f_9 / f_{positive\ min}< -6\).

10. The optical lens according to claim 1, characterized in that, The optical lens satisfies one or more of the following conditional expressions: The focal length \(f_1\) of the first lens and the focal length \(f_9\) of the ninth lens satisfy: \(0.05 < f_1 / f_9< 0.3\); The focal length \(f_4\) of the fourth lens and the focal length \(f_5\) of the fifth lens satisfy: \(6.5 < |f_4 / f_5|< 25\).

Images