Optical lens

Abstract

The application provides an optical lens, which comprises, in sequence from an object side to an imaging surface along an optical axis, a first lens with positive refractive power, the object side of which is a convex surface; a second lens with negative refractive power, the object side of which is a concave surface; a third lens with positive refractive power, the object side of which is a convex surface; a fourth lens with refractive power, the image side of which is a convex surface; a diaphragm; a fifth lens with positive refractive power, the object side of which is a convex surface; a sixth lens with negative refractive power, the object side of which is a concave surface; a seventh lens with positive refractive power, the image side of which is a convex surface; an eighth lens with positive refractive power, the image side of which is a convex surface; and a ninth lens with negative refractive power, the object side of which is a concave surface; wherein the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy 1.7 < TTL / f < 2.6. The optical lens provided by the application has the advantages of small volume, large imaging surface, large aperture and high pixels.

Description

TECHNICAL FIELD

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

[0002] With the development of mobile Internet, plus the popularity of social, video, live software, people's love for photography is getting higher and higher, and the pursuit of imaging effect is more diversified, which requires not only high image quality, but also a large field of view to shoot a wide range of visual impact strong picture.

[0003] At present, the development of unmanned aerial vehicles is rapid, and the demand for optical lenses matched with them is also increasing. Since unmanned aerial vehicles are often used in complex environments such as severe vibration, high pressure and extreme temperature, the performance requirements of the optical lenses matched with them are very high. They not only need to have good thermal stability to adapt to the harsh outdoor environment, but also need to have a light appearance and a small weight to increase the endurance time of the unmanned aerial vehicle in high-altitude flight. At the same time, the lens also needs to have a large aperture to meet the needs of the unmanned aerial vehicle to shoot clear and lively pictures in various environments such as day and night. At present, the conventional optical lenses on the market are difficult to meet the diversified use requirements of unmanned aerial vehicles. SUMMARY

[0004] In view of the above technical problems, the purpose of the present application is to provide an optical lens which can at least solve one of the above technical problems.

[0005] To achieve the above purpose, the present application provides an optical lens, which is sequentially arranged along the optical axis from the object side to the imaging surface: a first lens with positive refractive power, the object side surface of which is convex; a second lens with negative refractive power, the object side surface of which is concave; a third lens with positive refractive power, the object side surface of which is convex; a fourth lens with refractive power, the image side surface of which is convex; a diaphragm; a fifth lens with positive refractive power, the object side surface of which is convex; a sixth lens with negative refractive power, the object side surface of which is concave; a seventh lens with positive refractive power, the image side surface of which is convex; an eighth lens with positive refractive power, the image side surface of which is convex; a ninth lens with negative refractive power, the object side surface of which is concave; wherein the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.7 < TTL / f < 2.6.

[0006] Compared with the prior art, the present application has the following advantages: the optical lens provided by the present application adopts a combination of nine lenses, and by reasonably setting the refractive power of each lens and the surface shape of each lens, and reasonably setting the thickness of each lens and the spacing between each lens, the total length and volume of the optical lens can be effectively reduced, and the optical lens also has the characteristics of large image surface, large aperture and high pixels. BRIEF DESCRIPTION OF DRAWINGS

[0007] Figure 1 A structure diagram of an optical lens of Embodiment 1 of the present application.

[0008] Figure 2 A distortion curve of the optical lens in Embodiment 1 of the present application.

[0009] Figure 3 An MTF curve of the optical lens in Embodiment 1 of the present application.

[0010] Figure 4 A curve of the optical lens in Embodiment 1 of the present application.

[0011] Figure 5 A structure diagram of an optical lens of Embodiment 2 of the present application.

[0012] Figure 6 A distortion curve of the optical lens in Embodiment 2 of the present application.

[0013] Figure 7 An MTF curve of the optical lens in Embodiment 2 of the present application.

[0014] Figure 8 A curve of the optical lens in Embodiment 2 of the present application.

[0015] Figure 9 A structure diagram of an optical lens of Embodiment 3 of the present application.

[0016] Figure 10 A distortion curve of the optical lens in Embodiment 3 of the present application.

[0017] Figure 11 An MTF curve of the optical lens in Embodiment 3 of the present application.

[0018] Figure 12 A curve of the optical lens in Embodiment 3 of the present application. DETAILED DESCRIPTION

[0019] For a better understanding of the present application, various aspects of the present application will be described in more detail below with reference to the accompanying drawings. It is to be understood that the detailed description is merely descriptive of embodiments of the present application and is not intended to 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.

[0020] It should be noted that the expressions first, second, third, etc. in this specification 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.

[0021] In the drawings, the thickness, size, and shape of the lenses have been exaggerated slightly for ease of explanation. Specifically, the shape of the spherical or aspherical surface shown in the drawings is shown by way of example. That is, the shape of the spherical or aspherical surface is not limited to the shape of the spherical or aspherical surface shown in the drawings. The drawings are merely examples and are not drawn to scale.

[0022] In this document, the paraxial region refers to a region near the optical axis. If the 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 the 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.

[0023] It should also be understood that the words "comprise", "comprising", "include", "including", and / or "contain", 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. In addition, when describing the embodiments of the present application, the word "may" means "one or more embodiments of the present application". Also, the word "exemplary" is intended to mean an example or an illustration.

[0024] 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 should also be understood that the terms 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.

[0025] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the drawings and in conjunction with the embodiments.

[0026] The optical lens according to an embodiment of the present application comprises, along an optical axis from an object side to an image side, in order: a first lens, a second lens, a third lens, a fourth lens, a stop, a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, and a filter, and the optical centers of the lenses are located on the same straight line.

[0027] The first lens has positive refractive power, the object side surface is a convex surface, and the image side surface is a concave surface; the second lens has negative refractive power, the object side surface is a concave surface, and the image side surface is a concave surface; the third lens has positive refractive power, the object side surface is a convex surface, and the image side surface is a concave surface or a convex surface; the fourth lens has positive refractive power or negative refractive power, the object side surface is a convex surface or a concave surface, and the image side surface is a convex surface; the fifth lens has positive refractive power, the object side surface is a convex surface, and the image side surface is a convex surface; the sixth lens has negative refractive power, the object side surface is a concave surface, and the image side surface is a concave surface; the seventh lens has positive refractive power, the object side surface is a convex surface, and the image side surface is a convex surface; the eighth lens has positive refractive power, the object side surface is a convex surface, and the image side surface is a convex surface; and the ninth lens has negative refractive power, the object side surface is a concave surface, and the image side surface is a convex surface.

[0028] In some embodiments, the diaphragm is arranged between the fourth lens and the fifth lens, so as to converge the light rays of the diaphragm front lens group, and make the diaphragm front lens group more uniform in structure compared with the diaphragm rear lens group, thereby facilitating the increase of the imaging range of the optical lens and the reduction of the correction difficulty of various aberrations in the optical lens.

[0029] In some embodiments, the third lens and the fourth lens can be bonded to form a bonded lens, and the sixth lens and the seventh lens can be bonded to form a bonded lens, so as to share the correction of chromatic aberration of the optical lens, improve the resolution of the optical lens, and make the structure of the optical lens more compact, thereby facilitating the miniaturization of the optical lens.

[0030] In some embodiments, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.7 < TTL / f < 2.6. The above range can effectively limit the length and volume of the optical lens, and realize the miniaturization of the optical lens. More preferably, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.9 < TTL / f < 2.4.

[0031] In some embodiments, the effective focal length f of the optical lens and the maximum field of view FOV of the optical lens satisfy: 8.0 mm < f x tan(FOV / 2) < 11.0 mm. The above range can ensure that the optical lens has a larger field of view and imaging range, and can better match the chip imaging requirements of a large target surface. More preferably, the effective focal length f of the optical lens and the maximum field of view FOV of the optical lens satisfy: 9.0 mm < f x tan(FOV / 2) < 10.0 mm.

[0032] In some embodiments, the effective focal length f of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 1.2 < f / EPD < 1.4. The above range can make the optical lens have the characteristics of a super large aperture, have sufficient light quantity in the case of ensuring the imaging quality, and meet the imaging requirements of bright and dark environments.

[0033] In some embodiments, the effective focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: 2.0 < f1 / f < 5.0. By satisfying the above range, the deflection degree of the edge light is effectively reduced by reasonably setting the refractive power of the first lens, which is beneficial to the subsequent lens in correcting aberration and improves the imaging quality of the optical lens.

[0034] In some embodiments, the effective focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: -1.0 < f2 / f < -0.2. By satisfying the above range, the light is smoothly transitioned, and the aberration caused by the excessive deflection of the light through the first lens is corrected, which improves the imaging quality of the optical lens.

[0035] In some embodiments, the effective focal length f2 of the second lens and the combined focal length f34 of the third lens and the fourth lens satisfy: -1.0 < f2 / f34 < -0.2. By satisfying the above range, the refractive power of the second lens, the third lens and the fourth lens can be reasonably distributed, which is beneficial to reducing higher-order aberration and making the optical lens have higher imaging quality.

[0036] In some embodiments, the effective focal length f1 of the first lens and the effective focal length f5 of the fifth lens satisfy: 2.0 < f1 / f5 < 7.0; and the effective focal length f5 of the fifth lens and the effective focal length f of the optical lens satisfy: 0.3 < f5 / f < 1.0. By satisfying the above range, the light is diverged by reasonably setting the focal length of the fifth lens and the focal length ratio of the fifth lens to the first lens, which increases the field of view angle and the imaging range of the optical lens.

[0037] In some embodiments, the combined focal length f67 of the sixth lens and the seventh lens and the effective focal length f of the optical lens satisfy: -3.0 < f67 / f < -2.0. When the value of f67 / f exceeds the upper limit, the combined refractive power of the sixth lens and the seventh lens is too strong, although it can achieve the purpose of converging light quickly to make the total optical length of the optical lens smaller, but the various aberrations generated are too large to be corrected, and the curvature of the lens increases, which increases the processing difficulty and system error. When the value of f67 / f exceeds the lower limit, the combined refractive power of the sixth lens and the seventh lens is too weak, although the various aberrations are relatively reduced, but the refractive ability is reduced, which leads to the increase of the total optical length of the optical lens.

[0038] In some embodiments, the effective focal length f8 of the eighth lens and the effective focal length f9 of the ninth lens satisfy: -4.0 < f8 / f9 < -2.0; and the effective focal length f9 of the ninth lens and the effective focal length f of the optical lens satisfy: -1.5 < f9 / f < -0.5. By satisfying the above range, the focal length of the ninth lens and the focal length ratio of the eighth lens to the ninth lens are reasonably controlled, which is beneficial to reducing the correction difficulty of astigmatism and coma of the optical lens and improving the imaging quality of the optical lens.

[0039] In some embodiments, the center thickness CT1 of the first lens, the center thickness CT2 of the second lens, the air gap AT12 between the first and second lenses on the optical axis, and the air gap AT23 between the second and third lenses on the optical axis satisfy the following: 0.70 < (CT1 + CT2) / (AT12 + AT23) < 0.85. Satisfying this range allows the light rays from the first lens to the third lens to converge, achieving a specific optical power, which is beneficial for obtaining a larger object-side field of view. Furthermore, it deflects the light rays converged by the first lens, reducing off-axis aberrations and improving the imaging quality of the optical lens.

[0040] In some embodiments, the center thickness CT5 of the fifth lens, the center thickness CT6 of the sixth lens, the center thickness CT7 of the seventh lens, the center thickness CT8 of the eighth lens, and the air gap AT56 between the fifth and sixth lenses on the optical axis satisfy the following condition: 0.80 < (CT5 + AT56) / (CT6 + CT7 + CT8) < 1.05. Satisfying this range allows the fifth to eighth lenses to converge the light rays of the optical system and achieve a specific optical power, which is beneficial for reducing the length and volume of the optical lens and increasing its field of view and imaging range.

[0041] In some embodiments, the center thickness CT8 of the eighth lens, the center thickness CT9 of the ninth lens, and the air gap AT89 between the eighth and ninth lenses on the optical axis satisfy: 6.5 < (CT8 + AT89) / CT9 < 7.2. By satisfying the above range and reasonably allocating the thickness and assembly gap of the eighth and ninth lenses, miniaturization of the optical lens can be achieved while ensuring manufacturability.

[0042] In some embodiments, the center thickness D of the lens with the largest center thickness among the first to ninth lenses is... MAX The center thickness D of the lens with the smallest center thickness MIN Satisfy: 5.7 < D MAX / D MIN <6.4. By meeting the above range and reasonably setting the thickness of each lens element, it is possible to effectively limit the surface shape of each lens element while maintaining the miniaturization of the optical lens, reduce the difficulty of lens processing, and ensure the machinability of the lens and the assemblability of the lens.

[0043] The application will be further described in the following embodiments. In each embodiment, the thickness, radius of curvature, 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 are included in the protection scope of the application.

[0044] Embodiment 1

[0045] 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, along the optical axis from the object side to the imaging surface S19, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a diaphragm ST, a fifth lens L5, a sixth lens L6, a seventh lens L7, an eighth lens L8, a ninth lens L9 and a filter G1.

[0046] Specifically, the first lens L1 has positive 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 concave surface; the third lens L3 has positive focal power, the object side S5 is a convex surface, and the image side is a convex surface; the fourth lens L4 has negative focal power, the object side is a concave surface, and the image side S7 is a convex surface, and the third lens L3 and the fourth lens L4 are cemented to form a cemented lens, and the cemented surface is S6; the fifth lens L5 has positive focal power, the object side S8 is a convex surface, and the image side S9 is a convex surface; the sixth lens L6 has negative focal power, the object side S10 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 S12 is a convex surface, and the sixth lens L6 and the seventh lens L7 are cemented to form a cemented lens, and the cemented surface is S11; the eighth lens L8 has positive focal power, the object side S13 is a convex surface, and the image side S14 is a convex surface; the ninth lens L9 has negative focal power, the object side S15 is a concave surface, and the image side S16 is a convex surface; the filter G1 has a plane object side S17 and a plane image side S18. Among them, the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, the seventh lens L7, the eighth lens L8 and the ninth lens L9 are all glass spherical lenses.

[0047] The related parameters of each lens in the optical lens in the embodiment 1 are shown in Table 1.

[0048] Table 1

[0049]

[0050]

[0051] Figure 2 A distortion curve diagram of the embodiment 1 is shown, which represents the distortion at different fields of view on the imaging surface, the horizontal axis represents percentage (unit: %), and the vertical axis represents half field angle (unit: °). It can be seen from the diagram that the distortion of the embodiment is controlled within -9%, which indicates that the distortion of the optical lens is well corrected.

[0052] Figure 3 A modulation transfer function (MTF) curve diagram of the embodiment 1 is shown, which represents the imaging modulation degree of different spatial frequencies under each field of view, the horizontal axis represents spatial frequency (unit: lp / mm), and the vertical axis represents MTF value. It can be seen from the diagram that the MTF value of the embodiment is above 0.35 within the full field of view, and has good imaging quality and good detail resolution ability in the case of low frequency and high frequency.

[0053] Figure 4 A curve diagram of the axial chromatic aberration of the embodiment 1 is shown, which represents the chromatic aberration of different image heights on the imaging surface with respect to the central wavelength (0.550 μm) at each wavelength, the horizontal axis represents the axial chromatic aberration value of each wavelength relative to the central wavelength (unit: μm), and the vertical axis represents the normalized field angle. It can be seen from the diagram that the axial chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±6.0 μm, which indicates that the optical lens can well correct the chromatic aberration of the edge field of view and the secondary spectrum of the entire image surface.

[0054] Embodiment 2

[0055] Please refer to Figure 5 , which is a structural schematic diagram of the optical lens 200 provided in the embodiment 2 of the present application, the optical lens comprises, along the optical axis from the object side to the imaging surface S21, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a diaphragm ST, a fifth lens L5, a sixth lens L6, a seventh lens L7, an eighth lens L8, a ninth lens L9 and a filter G1.

[0056] Specifically, the first lens L1 has positive optical power, with its object-side surface S1 being convex and its image-side surface S2 being concave; the second lens L2 has negative optical power, with its object-side surface S3 being concave and its image-side surface S4 being concave; the third lens L3 has positive optical power, with its object-side surface S5 being convex and its image-side surface S6 being concave; the fourth lens L4 has positive optical power, with its object-side surface S7 being convex and its image-side surface S8 being convex; and the fifth lens L5 has positive optical power, with its object-side surface S9 being convex and its image-side surface S10 being convex. The first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, the seventh lens L7, the eighth lens L8, and the ninth lens L9 are all glass spherical lenses. The sixth lens L6 has negative optical power, with its object-side surface S13 and image-side surface S14 being convex. The eighth lens L8 has positive optical power, with its object-side surface S15 and image-side surface S16 being convex. The ninth lens L9 has negative optical power, with its object-side surface S17 being concave and its image-side surface S18 being convex. The filter G1 has object-side surface S19 and image-side surface S20 both being planar.

[0057] The relevant parameters of each lens in the optical lens of Example 2 are shown in Table 2.

[0058] Table 2

[0059]

[0060] Figure 6 to Figure 8 The distortion curve, modulation transfer function (MTF) curve, and transverse chromatic aberration curve of Example 2 are shown respectively. As can be seen from the figures, the distortion is controlled within -8%, indicating that the optical lens achieves good distortion correction; the MTF value of the optical lens is above 0.45 across the entire field of view, and it exhibits good imaging quality and good detail resolution at both low and high frequencies; the transverse chromatic aberration at the longest and shortest wavelengths is controlled within ±3.0 μm, indicating that the optical lens can excellently correct chromatic aberration at the edge of the field of view and the secondary spectrum of the entire image plane.

[0061] Example 3

[0062] Please see Figure 9 The diagram shown is a schematic diagram of the structure of the optical lens 300 provided in Embodiment 3 of the present invention. The optical lens includes, along the optical axis from the object side to the imaging surface S20, 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.

[0063] Specifically, the first lens L1 has positive refractive power, the object side S1 is a convex surface, and the image side S2 is a concave surface; the second lens L2 has negative refractive power, the object side S3 is a concave surface, and the image side S4 is a concave surface; the third lens L3 has positive refractive power, the object side S5 is a convex surface, and the image side is a convex surface; the fourth lens L4 has negative refractive power, the object side is a concave surface, and the image side S7 is a convex surface; the third lens L3 and the fourth lens L4 are cemented to form a cemented lens, and the cemented surface is S6; the fifth lens L5 has positive refractive power, the object side S8 is a convex surface, and the image side S9 is a convex surface; the sixth lens L6 has negative refractive power, the object side S10 is a concave surface, and the image side S11 is a concave surface; the seventh lens L7 has positive refractive power, the object side S12 is a convex surface, and the image side S13 is a convex surface; the eighth lens L8 has positive refractive power, the object side S14 is a convex surface, and the image side S15 is a convex surface; the ninth lens L9 has negative refractive power, the object side S16 is a concave surface, and the image side S17 is a convex surface; the filter G1 has a flat object side S18 and a flat image side S19. The first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, the seventh lens L7, the eighth lens L8, and the ninth lens L9 are all glass spherical lenses.

[0064] The related parameters of the lenses in the optical lens in Example 3 are shown in Table 3.

[0065] Table 3

[0066]

[0067]

[0068] Figure 10 to Figure 12 The distortion curve, the modulation transfer function (MTF) curve, and the axial chromatic aberration curve of Example 3 are shown respectively. As can be seen from the figures, the optical distortion is controlled within -9%, which indicates that the distortion of the optical lens is well corrected; the MTF value of the optical lens is above 0.45 in the full field of view, and has good imaging quality and good detail resolution ability in both low frequency and high frequency cases; the axial chromatic aberration of the longest wavelength and the shortest wavelength is controlled within ±6.0 μm, which indicates that the optical lens can very well correct the chromatic aberration of the edge field of view and the secondary spectrum of the entire image plane.

[0069] Please refer to Table 4 for the optical properties corresponding to each of the above examples, including the effective focal length f of the optical lens, the maximum field of view FOV, the total optical length TTL, and the numerical value corresponding to each conditional expression in the example.

[0070] Table 4

[0071]

[0072]

[0073] In the description of the present specification, the description of 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 expressions of the above terms do not necessarily refer to the same embodiment or example. Also, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0074] The above-described embodiments only express several implementation manners of the present application, which are described in a more specific and detailed manner, but cannot be understood as a limitation on the patent scope of the present application. It should be noted that, for those of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present application, which are all within the protection scope of the present application. Therefore, the patent protection scope of the present application should be subject to the appended claims.

Claims

1. An optical lens, comprising nine pieces of lenses, characterized in that, In order from the object side to the imaging surface along the optical axis, there are: a first lens with positive refractive power, an object side surface of the first lens being convex; a second lens with negative refractive power, an object side surface of the second lens being concave; a third lens with positive refractive power, an object side surface of the third lens being convex; a fourth lens with refractive power, an image side surface of the fourth lens being convex; a fifth lens with positive refractive power, an object side surface of the fifth lens being convex; a sixth lens with negative refractive power, an object side surface of the sixth lens being concave; a seventh lens with positive refractive power, an image side surface of the seventh lens being convex; an eighth lens with positive refractive power, an image side surface of the eighth lens being convex; a ninth lens with negative refractive power, an object side surface of the ninth lens being concave; wherein an overall optical length TTL of the optical lens and an effective focal length f of the optical lens satisfy: 1.7 < TTL / f < 2.6; a combined focal length f67 of the sixth lens and the seventh lens and the effective focal length f of the optical lens satisfy: -3.0 < f67 / f < -2.

0.

2. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and a maximum field angle FOV of the optical lens satisfy: 8.0 mm < f x tan(FOV / 2) < 11.0 mm.

3. The optical lens of claim 1, wherein, The effective focal length f of the optical lens and an entrance pupil diameter EPD of the optical lens satisfy: 1.2 < f / EPD < 1.

4.

4. The optical lens of claim 1, wherein, An effective focal length f1 of the first lens and the effective focal length f of the optical lens satisfy: 2.0 < f1 / f < 5.

0.

5. The optical lens of claim 1, wherein, An effective focal length f2 of the second lens and a combined focal length f34 of the third lens and the fourth lens satisfy: -1.0 < f2 / f34 < -0.

2.

6. The optical lens of claim 1, wherein, An effective focal length f1 of the first lens and an effective focal length f5 of the fifth lens satisfy: 2.0 < f1 / f5 < 7.

0.

7. The optical lens of claim 1, wherein, An overall optical length TTL of the optical lens and an effective focal length f of the optical lens satisfy: 1.9 < TTL / f < 2.4; A combined focal length f67 of the sixth lens and the seventh lens and the effective focal length f of the optical lens satisfy: -2.741 ≤ f67 / f ≤ -2.

231.

8. The optical lens of claim 1, wherein, An effective focal length f8 of the eighth lens and an effective focal length f9 of the ninth lens satisfy: -4.0 < f8 / f9 < -2.

0.

9. The optical lens of claim 1, wherein, The center thickness D of the lens having the largest center thickness among the first to ninth lenses MAX The center thickness D of the lens having the smallest center thickness MIN 5.7 < D < 6.4 is satisfied MAX D < 6.4 is satisfied MIN D < 6.4 is satisfied 10. The optical lens of claim 1, wherein, A central thickness CT1 of the first lens, a central thickness CT2 of the second lens, an air separation AT12 of the first lens and the second lens on the optical axis, and an air separation AT23 of the second lens and the third lens on the optical axis satisfy: 0.70 < (CT1+CT2) / (AT12+AT23) < 0.85.

Images