Optical lens

Abstract

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

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of imaging lenses, in particular to an optical lens. BACKGROUND

[0002] In the field of modern sports image capture, high-performance portable optical systems are the core demand. The current market sports camera lenses mostly adopt large-aperture, ultra-wide-angle design to adapt to high-speed motion scenes and extreme environment shooting. However, these traditional optical structures generally have the problems of declining imaging quality in weak light environment and insufficient dynamic range. At the same time, the increase of the field of view angle of the lens leads to difficulty in system aberration correction and decline of imaging quality; and the existing lens imaging target surface is small, which is difficult to meet market demand. SUMMARY

[0003] In view of the above problems, the purpose of the present application is to provide an optical lens with the advantages of excellent imaging quality.

[0004] To achieve the above purpose, the technical scheme adopted by the present application is: An optical lens has nine lenses with optical power, which includes, along the optical axis from the object side to the 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, whose image side surface is a convex surface; a ninth lens with negative optical power, whose image side surface is a concave surface; The real image height IH corresponding to the maximum field of view angle of the optical lens and the effective focal length f of the optical lens satisfy: 2.6<IH / f<3.2.

[0005] Further 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 real image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 1.7<TTL / IH<2.1.

[0006] It is further preferred that the optical lens satisfies one or more of the following conditional expressions: the maximum field of view angle FOV of the optical lens and the aperture value Fno of the optical lens satisfy: 65° < FOV / Fno < 75°; the real image height IH corresponding to the maximum field of view angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 6.5 < IH / EPD < 8.

[0007] It is further preferred that the optical lens satisfies one or more of the following conditional expressions: the total track length TTL of the optical lens, the real image height IH corresponding to the maximum field of view angle of the optical lens and the maximum field of view 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 real image height IH corresponding to the maximum field of view angle of the optical lens and the maximum field of view angle FOV of the optical lens satisfy: 55° < f×FOV / IH < 65°.

[0008] It is further preferred that the optical lens satisfies one or more of the following conditional expressions: the real image height IH corresponding to the maximum field of view angle of the optical lens and the effective focal length f of the optical lens satisfy: 2.83 < IH / f < 3; the object side half light entrance radius d1 of the first lens, the real image height IH corresponding to the maximum field of view angle of the optical lens and the maximum field of view angle FOV of the optical lens satisfy: 0.03 < d1 / (IH / 2) / tan(FOV / 2) < 0.06; the real image height IH corresponding to the maximum field of view angle of the optical lens, the effective focal length f of the optical lens and the radian value θ of the maximum half field of view angle of the optical lens satisfy: 0.9 < (IH / 2) / (f×θ) < 0.1.

[0009] 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.

[0010] 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.

[0011] Further preferably, 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.

[0012] It is further preferred that the optical lens satisfies one or more of the following conditional expressions: the focal length of the first lens f1 and the maximum focal length fmax in all the lenses with negative focal length satisfy: 1.2 < f1 / fmax < 1.7; the focal length of the ninth lens f9 and the minimum focal length fmin in all the lenses with positive focal length satisfy: -10.5 < f9 / fmin < -6.

[0013] It is further preferred that the optical lens satisfies one or more of the following conditional expressions: the focal length of the first lens f1 and the focal length of the ninth lens f9 satisfy: 0.05 < f1 / f9 < 0.3; the focal length of the fourth lens f4 and the focal length of the fifth lens f5 satisfy: 6.5 < |f4 / f5| < 25.

[0014] The optical lens provided by the present application adopts nine lenses with specific focal lengths, and through specific surface shape matching and reasonable focal length distribution, the imaging quality of the optical lens can be improved, the aberration can be reduced, and the imaging quality of the optical lens can be improved, so that the lens has one or more advantages such as miniaturization, large field of view, large image surface, high pixel, high imaging quality, and the like. BRIEF DESCRIPTION OF DRAWINGS

[0015] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the following description, taken in conjunction with the following drawings, in which: Figure 1 FIG. 1 is a structural schematic diagram of an optical lens according to an embodiment of the present application.

[0016] Figure 2 FIG. 2 is an F-Theta distortion curve diagram of the optical lens according to the embodiment of the present application.

[0017] Figure 3 FIG. 3 is an axial aberration curve diagram of the optical lens according to the embodiment of the present application.

[0018] Figure 4 FIG. 4 is an MTF curve diagram of the optical lens according to the embodiment of the present application.

[0019] Figure 5 FIG. 5 is a structural schematic diagram of an optical lens according to another embodiment of the present application.

[0020] Figure 6 FIG. 6 is an F-Theta distortion curve diagram of the optical lens according to the embodiment of the present application.

[0021] Figure 7Axial aberration curve of the optical lens in Embodiment 2 of the present application.

[0022] Figure 8 MTF curve of the optical lens in Embodiment 2 of the present application.

[0023] Figure 9 Structure diagram of the optical lens in Embodiment 3 of the present application.

[0024] Figure 10 F-Theta distortion curve of the optical lens in Embodiment 3 of the present application.

[0025] Figure 11 Axial aberration curve of the optical lens in Embodiment 3 of the present application.

[0026] Figure 12 MTF curve of the optical lens in Embodiment 3 of the present application.

[0027] The following detailed description will further describe the present application with reference to the above-mentioned drawings. DETAILED DESCRIPTION

[0028] For better understanding of the present application, various aspects of the present application will be described in more detail with reference to the drawings. It should be understood that these detailed descriptions are only descriptions of embodiments of the present application and do not limit the scope of the present application in any way. Throughout the specification, like reference numerals refer to like elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0029] It should be noted that, in the present specification, the expressions first, second, third, and the like are merely used to distinguish one feature from another feature, and do not represent any limitation on the features. Therefore, the first lens discussed below can also be referred to as the second lens or the third lens without departing from the teachings of the present application.

[0030] In the drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for ease of explanation. Specifically, the shape of the spherical surface or aspherical surface shown in the drawings is shown by way of example. That is, the shape of the spherical surface or aspherical surface is not limited to the shape of the spherical surface or aspherical surface shown in the drawings. The drawings are merely examples and are not drawn strictly to scale.

[0031] In this context, the paraxial region refers to a region near the optical axis. If a lens surface is convex and the position of the convex surface is not specified, it means that the lens surface is convex at least in the paraxial region. If a lens surface is concave and the position of the concave surface is not specified, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the object is referred to as the object side surface of the lens, and the surface of each lens closest to the imaging surface is referred to as the image side surface of the lens.

[0032] It should also be understood that the words "comprise," "comprising," "include," "including," and / or "has," "having," when used in this specification, specify the presence of stated features, elements, and / or components, but do not preclude the presence or addition of one or more other features, elements, components, and / or groups thereof. Furthermore, when describing the embodiments of the present application, the use of "or" means "and / or" unless strictly dictated otherwise by context. Also, the use of "a" or "an" means "one or more" unless otherwise clearly indicated by context. Finally, the term "exemplary" is used herein to mean "an example of. "

[0033] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0034] It should be noted that the embodiments and features in the embodiments of the present application can be combined with each other without conflict. The present application will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0035] The optical lens of the embodiment of the present application has nine lenses with optical power, which are sequentially arranged along the optical axis from the object side to the imaging surface as follows: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, and a ninth lens.

[0036] In some embodiments, the first lens can have negative optical power, the object side surface of which is convex, and the image side surface of which is concave. The second lens can have negative optical power, the object side surface of which is concave, and the image side surface of which is convex. The third lens can have positive optical power, the object side surface of which is convex, and the image side surface of which is convex. The fourth lens can have positive optical power or negative optical power, the object side surface of which is concave, and the image side surface of which is convex. The fifth lens can have positive optical power, the object side surface of which is convex, and the image side surface of which is convex. The sixth lens can have negative optical power, the object side surface of which can be concave or convex, and the image side surface of which is concave. The seventh lens can have positive optical power, the object side surface of which is convex, and the image side surface of which is convex. The eighth lens can have positive optical power or negative optical power, the object side surface of which can be concave or convex, and the image side surface of which is convex. The ninth lens can have negative optical power, the object side surface of which can be concave or convex, and the image side surface of which is concave.

[0037] In some embodiments, the optical lens can further include a diaphragm, which can be located between the fourth lens and the fifth lens. It can be understood that the diaphragm is used to limit the amount of light to change the brightness of the imaging.

[0038] In some embodiments, the optical lens can further include a filter disposed between the ninth lens and the imaging surface. The filter is used to filter out interference light to prevent the interference light from reaching the imaging surface of the optical lens and affecting normal imaging.

[0039] In some embodiments, the sixth lens and the seventh lens can be cemented to form a cemented lens group with optical power, which can effectively correct the chromatic aberration of the optical lens, reduce the sensitivity of the optical lens to decentration, balance the aberration of the optical lens, and improve the imaging quality of the optical lens. In addition, the combination of the sixth lens and the seventh lens 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 of the sixth lens and the seventh lens f and the effective focal length f of the optical lens satisfy: 12<|f / f|<150. More specifically, 12.35<|f / f|<143.8.

[0040] In some embodiments, the real image height IH corresponding to the maximum field of view 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 can control the image height and the focal length of the optical lens within a reasonable range, which helps the optical lens to have a large image surface and improve the imaging quality. More specifically, 2.83<IH / f<3.

[0041] In some embodiments, 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. Satisfying the above range can effectively limit the length of the lens, which is conducive to the miniaturization of the optical lens. More specifically, 5.12<TTL / f<5.97.

[0042] In some embodiments, the total optical length TTL of the optical lens and the real image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 1.7<TTL / IH<2.1. Satisfying the above range ensures that the lens has a large image surface under the condition of the same total length, which can match a large-size imaging chip to realize high-definition imaging, and better realize the balance between the small total length and the large image surface of the lens. More specifically, 1.79<TTL / IH<2.01.

[0043] In some embodiments, the maximum field of view angle FOV of the optical lens and the aperture value Fno of the optical lens satisfy: 65°<FOV / Fno<75°. Satisfying the above range can limit the optical lens to have a suitable field of view angle and aperture value, which can collect light rays at a large angle and obtain good imaging quality. More specifically, 70.3°<FOV / Fno<70.5°.

[0044] In some embodiments, the real image height IH corresponding to the maximum field of view angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 6.5<IH / EPD<8. Satisfying the above range can increase the width of the light beam entering the optical lens, so that the brightness of the optical lens at the image plane is improved to avoid the generation of dark corners. More specifically, 7.08<IH / EPD<7.47.

[0045] In some embodiments, the total optical length TTL of the optical lens, the real image height IH corresponding to the maximum field of view angle of the optical lens, and the maximum field of view angle FOV of the optical lens satisfy: 7<180°×TTL / (IH / 2) / (FOV / 2)<8.5. Satisfying the above range can balance the image height, focal length, and total optical length to improve the imaging quality of the optical lens. More specifically, 7.35<180°×TTL / (IH / 2) / (FOV / 2)<8.18.

[0046] In some embodiments, the effective focal length f of the optical lens, the real image height IH corresponding to the maximum field of view angle of the optical lens, and the maximum field of view angle FOV of the optical lens satisfy: 55°<f×FOV / IH<65°. Satisfying the above condition formula can reasonably limit the relationship between the focal length, field of view angle, and image height of the optical lens, which is conducive to achieving a balance between the field of view angle and large target surface imaging of the optical lens, and better meets the use requirement of high-image-quality shooting of the optical lens. More specifically, 58.94°<f×FOV / IH<62.08°.

[0047] In some embodiments, the half light entrance radius d1 of the object side of the first lens, the real image height IH corresponding to the maximum field of view angle of the optical lens, and the maximum field of view angle FOV of the optical lens satisfy: 0.03<d1 / (IH / 2) / tan(FOV / 2)<0.06. Satisfying the above range can ensure the balance between the size of the optical lens and the field of view angle and the image plane.

[0048] In some embodiments, the real image height IH corresponding to the maximum field of view angle of the optical lens, the effective focal length f of the optical lens, and the radian value θ of the maximum half field of view angle of the optical lens satisfy: 0.9<(IH / 2) / (f×θ)<0.1. Satisfying the above range can make the lens have a smaller distortion value, which can provide a high-definition imaging effect. More specifically, 0.91<(IH / 2) / (f×θ)<0.98.

[0049] 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. Satisfying the above range, the first lens has an appropriate negative focal length, which is conducive to expanding the field of view angle of the optical lens. More specifically, -2.02<f1 / f<-1.45.

[0050] 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. This range satisfies that the second lens also adopts a negative lens, which can further diverge the light rays and improve the field angle of the imaging system. More specifically, -3.48 < f2 / f < -2.14.

[0051] 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. This range satisfies that the third lens converges the front-end incident light rays appropriately, which is beneficial to correct the aberration and the edge field distortion caused by the first lens and the second lens, so that the lens has smaller distortion and can provide high-definition imaging effect. More specifically, 1.47 < f3 / f < 2.14.

[0052] 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. This range satisfies that the various aberrations of the optical lens are fully corrected, which can improve the resolution and achieve high resolution. More specifically, 11.62 < |f4 / f| < 36.66.

[0053] 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. This range satisfies that the light rays are smoothly transitioned, which is beneficial to the correction of astigmatism and field curvature and improves the imaging quality of the optical lens and ensures the stability of the optical system. More specifically, 1.52 < f5 / f < 1.77.

[0054] 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. This range satisfies that the sixth lens with negative focal length and the seventh lens with positive focal length cooperate, which can adjust the optical path difference between different fields of view, improve the resolution, and is beneficial to the smooth entry of the light rays into the rear lens, which can further reduce the field curvature and correct the off-axis point aberration of the optical lens. More specifically, -1.29 < f6 / f < -1.03; 1.19 < f7 / f < 1.6.

[0055] 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. This range satisfies that the various aberrations of the optical lens are fully corrected, which can improve the resolution and achieve high resolution. More specifically, 4.34 < |f8 / f| < 351.6.

[0056] 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 focal length, the incident light is diverged to a greater extent, so that the peripheral light and the central light are turned upward to a higher imaging position, better achieving large target surface imaging of the lens and improving the imaging quality. More specifically, -15.82 < f9 / f < -7.81.

[0057] In some embodiments, the combined focal length fb of the lenses located after the diaphragm 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 located after the diaphragm satisfy: -230 < (f5+f6+f7+f8+f9) / fb < -4.4. By setting the focal lengths of the lens group after the diaphragm, the above range is satisfied, which is conducive to balancing various aberrations generated by the lens group before the diaphragm and improving the overall imaging quality. More specifically, 1.58 < fb / f < 2.06; -224.52 < (f5+f6+f7+f8+f9) / fb < -4.82.

[0058] 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 f6+1 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 < f6+1 / (f6+f7) < -25. By satisfying the above range, the smooth transition of light is facilitated, the imaging quality of the optical lens is improved, and the stability of the optical system is ensured. More specifically, -1.05 < f6 / f7 < -0.7; -3247.19 < f6+1 / (f6+f7) < -26.8.

[0059] In some embodiments, the minimum focal length fpositive min of all lenses with positive focal length and the maximum focal length fnegative max of all lenses with negative focal length satisfy: -1.5 < fpositive min / fnegative max < -0.9; the focal length f1 of the first lens and the maximum focal length fnegative max of all lenses with negative focal length satisfy: 1.2 < f1 / fnegative max < 1.7; the focal length f9 of the ninth lens and the minimum focal length fpositive min of all lenses with positive focal length satisfy: -10.5 < f9 / fpositive min < -6. It can be understood that fpositive min is the minimum value of all positive focal length lenses, which has the greatest influence on the deflection of light; fnegative max is the maximum value of all negative focal length lenses, which has the greatest influence on the deflection of light. Satisfying the above range makes the influence on the deflection of light close, which is beneficial to balance the aberration of the optical lens. More specifically, -1.42 < fpositive min / fnegative max < -0.96; 1.28 < f1 / fnegative max < 1.58; -9.95 < f9 / fpositive min < -6.32.

[0060] 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. Satisfying the above range, by reasonably setting the focal length relationship of 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 entering the imaging surface is increased, which is beneficial to realize large image surface imaging of the lens, while increasing the amount of light entering, improving the relative luminance of the system. More specifically, 0.08 < f1 / f9 < 0.27.

[0061] 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. Satisfying the above range, by reasonably setting the focal length relationship of the lenses before and after the stop, the deflection of light can be avoided to be too large, and the correction difficulty of aberration is reduced. More specifically, 7 < |f4 / f5| < 23.96.

[0062] In some embodiments, the object side surface curvature radius R1 of the first lens and the image side surface curvature radius R2 of the first lens satisfy: 0.5 < (R1 - R2) / (R1 + R2) < 0.7; the object side surface curvature radius R3 of the second lens and the image side surface curvature radius R4 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 can collect as many large field angle light rays as possible and make the light rays smoothly enter the rear system, increase the light quantity of the optical lens, and effectively expand the field of view of the optical lens. More specifically, 0.5 < (R1 - R2) / (R1 + R2) < 0.64; -0.59 < (R3 - R4) / (R3 + R4) < -0.31.

[0063] In some embodiments, the object-side surface curvature radius R5 of the third lens and the image-side surface curvature radius R6 of the third lens satisfy: 1.4 < (R5-R6) / (R5+R6) < 5.8. Satisfying the above range is conducive to correcting aberrations and distortion of the edge field caused by the first lens and the second lens, making the lens have smaller distortion and being able to provide high-definition imaging effect. More specifically, 1.48 < (R5-R6) / (R5+R6) < 5.4.

[0064] In some embodiments, the object-side surface curvature radius R7 of the fourth lens and the image-side surface curvature radius R8 of the fourth lens satisfy: 0 < |(R7-R8) / (R7+R8)| < 0.2. Satisfying the above range is able to 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.

[0065] In some embodiments, the object-side surface curvature radius R9 of the fifth lens and the image-side surface curvature radius R10 of the fifth lens satisfy: -0.6 < (R9+R10) / (R9-R10) < 0.2. Satisfying the above range can make the fifth lens be double-convex, which is able to 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.

[0066] In some embodiments, the object-side surface curvature radius R13 of the seventh lens and the image-side surface curvature radius R14 of the seventh lens satisfy: -1 < (R13+R14) / (R13-R14) < -0.1. Satisfying the above range is conducive to converging light rays while correcting the field curvature and distortion of the optical lens, improving the imaging quality of the optical lens. More specifically, -0.96 < (R13+R14) / (R13-R14) < 0.1.

[0067] In some embodiments, the optical lens satisfies the following conditional expressions: 5mm < f < 6mm; 2mm < EPD < 2.4mm; 29mm < TTL < 32mm; 2.3 < Fno < 2.8; 11° < CRA < 35°; 4mm < BFL < 5.5mm; 170° < FOV < 180°; 15mm < IH < 17mm. 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 total track length of the optical lens, Fno represents the aperture value of the optical lens, CRA represents the chief ray angle of incidence at the maximum image height of the optical lens, BFL represents the back focal length of the optical lens, FOV represents the maximum field of view angle of the optical lens, and IH represents the real image height corresponding to the maximum field of view angle of the optical lens. The optical lens satisfies the above ranges and has one or more advantages such as miniaturization, large image surface, large aperture, large field of view angle, and the like. More specifically, 5.22mm < f < 5.74mm; 2.08mm < EPD < 2.3mm; 29.35mm < TTL < 31.22mm; 2.45 < Fno < 2.55; 11.86° < CRA < 34.86°; 4.41mm < BFL < 5.16mm; 175° < FOV < 177°; 15.62mm < IH < 16.32mm.

[0068] In some embodiments, the lens material in the optical lens provided by the present application 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 characteristics of the glass itself. The optical lens provided by the present application can adopt a full-glass lens structure, which can reduce dispersion, effectively correct the chromatic aberration of the optical lens, and improve the imaging quality.

[0069] 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 a spherical lens or an aspherical lens. Compared with a spherical structure, an 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 achieving miniaturization of the lens. More specifically, the second lens, the fifth lens, and the ninth lens of the present application adopt an aspherical lens; the eighth lens adopts an aspherical lens or a spherical lens; and the first lens, the third lens, the fourth lens, the sixth lens, and the seventh lens adopt a spherical lens.

[0070] In various embodiments of the present application, when the lens adopts an aspherical lens, the shape of each aspherical surface of the optical lens satisfies the following equation: ; Wherein, z is the distance of the curved surface and the curved surface vertex in the direction of the optical axis, h is the distance of the optical axis to the curved surface, c is the curvature of the curved surface vertex, K is the quadratic curved surface coefficient, B, C, D, E, F are the fourth order, sixth order, eighth order, tenth order, twelfth order curved surface coefficient respectively.

[0071] The application will be further described in the following embodiments. In each embodiment, the thickness, the radius of curvature, the material selection of each lens in the optical lens are different, and the specific differences can be referred to the parameter table of each embodiment. The following embodiments are only the preferred embodiments of the application, but the embodiments of the application are not limited to the following embodiments only, any changes, substitutions, combinations or simplifications made without departing from the innovative points of the application should be regarded as equivalent replacement, and all are included in the protection scope of the application.

[0072] Embodiment 1 Please refer to Figure 1 , which is a structural schematic diagram of the optical lens 100 provided in the embodiment 1 of the application, the optical lens includes in sequence from the object side to the imaging surface along the optical axis: the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the diaphragm ST, the fifth lens L5, the sixth lens L6, the seventh lens L7, the eighth lens L8, the ninth lens L9, and the filter G1.

[0073] The first lens L1 has negative focal power, the object side S1 is a convex surface, and the image side S2 is a concave surface; The second lens L2 has negative focal power, the object side S3 is a concave surface, and the image side S4 is a convex surface; The third lens L3 has positive focal power, the object side S5 is a convex surface, and the image side S6 is a convex surface; The fourth lens L4 has positive focal power, the object side S7 is a concave surface, and the image side S8 is a convex surface; The fifth lens L5 has positive focal power, the object side S9 is a convex surface, and the image side S10 is a convex surface; The sixth lens L6 has negative focal power, the object side S11 is a concave surface, and the image side is a concave surface; The seventh lens L7 has positive focal power, the object side is a convex surface, and the image side S13 is a convex surface; The sixth lens L6 and the seventh lens L7 form a cemented lens group with negative focal 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; The eighth lens L8 has positive focal power, the object side S14 is a convex surface, and the image side S15 is a convex surface; The ninth lens L9 has negative focal power, the object side S16 is a convex surface, and the image side S17 is a concave surface; The object side S18 and the image side S19 of the filter G1 are both flat surfaces. The imaging surface S20 is a flat surface.

[0074] The first lens, the third lens, the fourth lens, the sixth lens, the seventh lens and the eighth lens are glass spherical lenses, and the second lens, the fifth lens and the ninth lens are glass aspherical lenses.

[0075] The related parameters of the lenses in the optical lens 100 in Embodiment 1 are shown in Table 1-1.

[0076] Table 1-1 The surface type parameters of the aspherical lenses of the optical lens 100 in Embodiment 1 are shown in Table 1-2.

[0077] Table 1-2 In this embodiment, the F-Theta distortion curve, the axial aberration curve and the MTF curve of the optical lens 100 are shown in Figure 2 , Figure 3 , Figure 4 respectively.

[0078] Figure 2 The F-Theta distortion curve of Embodiment 1 is shown, which represents the F-Theta distortion of light rays at different image heights on the imaging surface, the horizontal axis represents the F-Theta distortion value (unit: %), and the vertical axis represents the half field angle (unit: °). As can be seen from the figure, the F-Theta distortion of the optical lens is controlled within ±5%, which shows that the optical lens can better correct the distortion.

[0079] Figure 3 The axial aberration curve of Embodiment 1 is shown, which represents the axial aberration of each wavelength on the optical axis at the imaging surface, 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 offset of the axial aberration is controlled within -0.02mm~0.04mm, which shows that the optical lens can better correct the axial aberration.

[0080] Figure 4 The MTF (Modulation Transfer Function) curve of Embodiment 1 is shown, which represents the imaging modulation degree of the lens at different spatial frequencies under each field of view, the horizontal axis represents the 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 embodiment is above 0.4 in the full field of view, and in the range of 0~160lp / mm, the MTF curve uniformly and smoothly decreases from the center to the edge of the field of view, and has good imaging quality and good detail resolution ability in the case of low frequency and high frequency.

[0081] Embodiment 2 Referring to Figure 5 , a structural diagram of an optical lens 200 provided in Embodiment 2 of the present application is shown. The optical lens of this embodiment is substantially the same as that of Embodiment 1, and the difference mainly lies in that the eighth lens L8 has a negative focal power; the object side S11 of the sixth lens L6 is a convex surface; the object side S14 of the eighth lens L8 is a concave surface; the eighth lens is a glass aspheric lens; and the optical parameters such as the curvature radius, aspheric coefficient and thickness of each lens surface type are different.

[0082] The related parameters of each lens in the optical lens 200 in Embodiment 2 are shown in Table 2-1.

[0083] Table 2-1 The surface type parameters of the aspheric lens of the optical lens 200 in Embodiment 2 are shown in Table 2-2.

[0084] Table 2-2 In this embodiment, the F-Theta distortion curve, axial aberration curve and MTF curve of the optical lens 200 are shown in Figure 6 , Figure 7 , Figure 8 respectively.

[0085] As can be seen from Figure 6 , the F-Theta distortion of the optical lens is controlled within-10%~5%, which indicates that the optical lens can correct the distortion well.

[0086] As can be seen from Figure 7 , the shift of the axial aberration is controlled within ±0.02mm, which indicates that the optical lens can correct the axial aberration well.

[0087] As can be seen from Figure 8 , the MTF value of this embodiment is above 0.38 in the full field of view, and the MTF curve is uniformly and smoothly decreased from the center to the edge of the field of view in the range of 0~160lp / mm, which has good imaging quality and good detail resolution ability in the case of low frequency and high frequency.

[0088] Embodiment 3 Referring to Figure 9, which is a structural schematic diagram of the optical lens 300 provided in Embodiment 3 of the present application. The optical lens of the present embodiment is substantially the same as that of Embodiment 1, with the difference mainly being that the fourth lens L4 has a negative focal power; the eighth lens L8 has a negative focal power; the sixth lens L6 and the seventh lens L7 form a cemented lens group with a positive focal power; the object side S11 of the sixth lens L6 is a convex surface; the object side S14 of the eighth lens L8 is a concave surface; the object side S16 of the ninth lens L9 is a concave surface; the eighth lens is a glass aspheric lens; and the optical parameters such as the curvature radius, aspheric coefficients and thickness of each lens surface are different.

[0089] The related parameters of each lens in the optical lens 300 in Embodiment 3 are shown in Table 3-1.

[0090] Table 3-1 The surface parameters of the aspheric lens of the optical lens 300 in Embodiment 3 are shown in Table 3-2.

[0091] Table 3-2 In the present embodiment, the F-Theta distortion curve, the axial aberration curve and the MTF curve of the optical lens 300 are shown in Figure 10 , Figure 11 , Figure 12 respectively.

[0092] As can be seen from Figure 10 , the F-Theta distortion of the optical lens is controlled within -10%~5%, which indicates that the optical lens can correct the distortion well.

[0093] As can be seen from Figure 11 , the shift of the axial aberration is controlled within ±0.02mm, which indicates that the optical lens can correct the axial aberration well.

[0094] As can be seen from Figure 12 , the MTF value of the present embodiment is above 0.48 in the full field of view, and the MTF curve is uniformly and smoothly decreased from the center to the edge of the field of view in the range of 0~120lp / mm, which has good imaging quality and good detail resolution ability in the case of low frequency and high frequency.

[0095] Please refer to Table 4-1 and Table 4-2, which are the optical properties corresponding to each of the above embodiments, including the effective focal length f, the total optical length TTL, the aperture value Fno, the real image height IH corresponding to the maximum field of view, the chief ray angle CRA at the maximum image height, the maximum field of view FOV and the numerical value corresponding to each condition in each embodiment.

[0096] Table 4-1 Table 4-2 In summary of the above embodiments, the optical lens provided by the present application adopts nine pieces of lenses with specific optical powers, and through specific surface shape matching and reasonable optical power distribution, the imaging quality of the optical lens can be improved, the aberration can be reduced, and the imaging quality of the optical lens can be improved, so that the lens has one or more advantages of miniaturization, large field of view, large image surface, high pixel, high imaging quality, etc.

[0097] In the description of the present specification, the description referring to the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0098] The above-described embodiments only express several implementation manners of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation on the patent scope of the present application. It should be noted that, for those skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are all within the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. An optical lens having nine pieces of lenses with optical power, characterized in that, In order from the object side to the imaging surface along the optical axis, the optical lens comprises in sequence: a first lens with negative refractive power, the object side surface of which is a convex surface, and the image side surface of which is a concave surface; a second lens with negative refractive power, the object side surface of which is a concave surface, and the image side surface of which is a convex surface; a third lens with positive refractive power, the object side surface of which is a convex surface, and the image side surface of which is a convex surface; a fourth lens with refractive power, the object side surface of which is a concave surface, and the image side surface of which is a convex surface; a fifth lens with positive refractive power, the object side surface of which is a convex surface, and the image side surface of which is a convex surface; a sixth lens with negative refractive power, the image side surface of which is a concave surface; a seventh lens with positive refractive power, the object side surface of which is a convex surface, and the image side surface of which is a convex surface; an eighth lens with refractive power, the image side surface of which is a convex surface; a ninth lens with negative refractive power, the image side surface of which is a concave surface; a real image height IH corresponding to a maximum field angle of the optical lens and an effective focal length f of the optical lens satisfy: 2.6 < IH / f < 3.

2.

2. The optical lens of claim 1, wherein, The optical lens satisfies one or more of the following conditional expressions: an optical total length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 5 < TTL / f < 6.5; the optical total length TTL of the optical lens and a real image height IH corresponding to a maximum field angle of the optical lens satisfy: 1.7 < TTL / IH < 2.

1.

3. The optical lens of claim 1, wherein, The optical lens satisfies one or more of the following conditional expressions: a maximum field angle FOV of the optical lens and an aperture value Fno of the optical lens satisfy: 65° < FOV / Fno < 75°; a real image height IH corresponding to a maximum field angle of the optical lens and an entrance pupil diameter EPD of the optical lens satisfy: 6.5 < IH / EPD < 8.

4. The optical lens of claim 1, wherein, The optical lens satisfies one or more of the following conditional expressions: an optical total length TTL of the optical lens, a real image height IH corresponding to a maximum field angle of the optical lens, and a maximum field angle FOV of the optical lens satisfy: 7 < 180°×TTL / (IH / 2) / (FOV / 2) < 8.5; an effective focal length f of the optical lens, a real image height IH corresponding to a maximum field angle of the optical lens, and a maximum field angle FOV of the optical lens satisfy: 55° < f×FOV / IH < 65°.

5. The optical lens of claim 1, wherein, The optical lens satisfies one or more of the following conditional expressions: a real image height IH corresponding to a maximum field angle of the optical lens and an effective focal length f of the optical lens satisfy: 2.83 < IH / f < 3; an object side surface half light entrance radius d1 of the first lens, a real image height IH corresponding to a maximum field angle of the optical lens, and a maximum field angle FOV of the optical lens satisfy: 0.03 < d1 / (IH / 2) / tan(FOV / 2) < 0.06; a real image height IH corresponding to a maximum field angle of the optical lens, an effective focal length f of the optical lens, and an arc value θ of a maximum half field angle of the optical lens satisfy: 0.9 < (IH / 2) / (f×θ) < 0.

1.

6. The optical lens of claim 1, wherein, 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 of claim 1, wherein, 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 + f + f8 + f9) / fb < -4.

4.

8. The optical lens of claim 1, wherein, 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 fglue1 of the sixth lens and the seventh lens and the effective focal length f of the optical lens satisfy: 12 < |fglue1 / 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 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.

9. The optical lens of claim 1, wherein, The optical lens satisfies one or more of the following conditional expressions: the smallest focal length f positive min among all lenses with positive refractive power and the largest focal length f negative max among all lenses with negative refractive power satisfy: -1.5 < f positive min / f negative max < -0.9; the focal length f1 of the first lens and the largest focal length f negative max among all lenses with negative refractive power satisfy: 1.2 < f1 / f negative max < 1.7; the focal length f9 of the ninth lens and the smallest focal length f positive min among all lenses with positive refractive power satisfy: -10.5 < f9 / f positive min < -6.

10. The optical lens of claim 1, wherein, 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.

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