Optical imaging system

Abstract

The present invention provides an optical imaging system, which sequentially includes, from the object side to the image side along the optical axis: a first lens with a positive optical power; a second lens with a negative optical power; a third lens with a negative optical power; a fourth lens with an optical power; a fifth lens with a positive optical power; a sixth lens with an optical power; a seventh lens with an optical power; an eighth lens with an optical power; a ninth lens with an optical power, and the object side surface of the ninth lens is convex; wherein, the following relationships are satisfied between the entrance pupil diameter EPD of the optical imaging system and the effective focal length f of the optical imaging system: f / EPD < 1.7; the following relationship is satisfied between the radius of curvature R17 of the object side surface of the ninth lens and the effective focal length f of the optical imaging system: 0 < R17 / f < 5; the following relationship is satisfied among the Abbe number V1 of the first lens, the Abbe number V2 of the second lens, and the Abbe number V3 of the third lens: 28 < (V1 + V2 + V3) / 3 < 32. The present invention solves the problem in the prior art that it is difficult to balance a large aperture and high resolution in an optical imaging system.

Description

Technical Field

[0001] The present invention relates to the technical field of optical imaging devices, and more particularly, to an optical imaging system. Background Art

[0002] As the usage scenarios of electronic products by consumers become more and more diversified, more and more consumers need to take pictures in low-light environments or even dark environments such as rainy days, evenings, early mornings, and nights. However, the current optical imaging systems installed on electronic products have problems such as darker shooting images, blurred details, and unclear shooting in dark environments, resulting in poor shooting effects.

[0003] Since lenses with large apertures have advantages such as more light input, brighter images, clearer details, and better night scenes, large apertures have become an obvious development trend for electronic products. However, imaging lenses with large apertures will lose some image quality in low-light environments, resulting in poor imaging quality for detailed shooting and being insufficient to support the requirements of electronic products for high resolution.

[0004] That is to say, there is a problem in the prior art that it is difficult to balance a large aperture and high resolution in an optical imaging system. Summary of the Invention

[0005] The main object of the present invention is to provide an optical imaging system to solve the problem in the prior art that it is difficult to balance a large aperture and high resolution in an optical imaging system.

[0006] To achieve the above object, according to one aspect of the present invention, an optical imaging system is provided. The optical imaging system is a nine-lens imaging system, which sequentially includes, along the optical axis from the object side to the image side: a first lens with a positive optical power; a second lens with a negative optical power; a third lens with a negative optical power; a fourth lens with an optical power; a fifth lens with a positive optical power; a sixth lens with an optical power; a seventh lens with an optical power; an eighth lens with an optical power; a ninth lens with an optical power, and the object side surface of the ninth lens is convex; wherein, the entrance pupil diameter EPD of the optical imaging system and the effective focal length f of the optical imaging system satisfy: f / EPD < 1.7; the radius of curvature R17 of the object side surface of the ninth lens and the effective focal length f of the optical imaging system satisfy: 0 < R17 / f < 5; the Abbe numbers V1 of the first lens, V2 of the second lens, and V3 of the third lens satisfy: 28 < (V1 + V2 + V3) / 3 < 32.

[0007] Furthermore, the image side surface of the ninth lens is concave, and the radius of curvature R17 of the object side surface of the ninth lens and the radius of curvature R18 of the image side surface of the ninth lens satisfy: 2.8 < R17 / R18 < 5.

[0008] Further, the object side surface of the fifth lens is concave, the image side surface of the fifth lens is convex, and the following conditions are satisfied between the curvature radius R9 of the object side surface of the fifth lens and the curvature radius R10 of the image side surface of the fifth lens: 0.5 < R9 / R10 < 4, and the following conditions are satisfied between the curvature radius R9 of the object side surface of the fifth lens and the effective focal length f5 of the fifth lens: -1 < R9 / f5 < 0.

[0009] Further, the object side surface of the sixth lens is convex, the image side surface of the sixth lens is concave, and the following conditions are satisfied between the curvature radius R11 of the object side surface of the sixth lens and the curvature radius R12 of the image side surface of the sixth lens: 0 < R11 / R12 < 4, and the following conditions are satisfied between the curvature radius R11 of the object side surface of the sixth lens and the effective focal length f of the optical imaging system: 0 < R11 / f < 4.

[0010] Further, the following conditions are satisfied between the central thickness CT4 of the fourth lens on the optical axis and the central thickness CT5 of the fifth lens on the optical axis: 1 < CT5 / CT4 < 5.

[0011] Further, the following conditions are satisfied between the central thickness CT1 of the first lens on the optical axis and the central thickness CTi of any one of the second to ninth lenses on the optical axis: CT1 / CTi > 1, where i takes values from 2, 3, 4, 5, 6, 7, 8, 9.

[0012] Further, the fourth lens has a positive optical power, both the object side surface and the image side surface of the fourth lens are convex, and the following conditions are satisfied between the effective focal length f4 of the fourth lens, the curvature radius R7 of the object side surface of the fourth lens, the curvature radius R8 of the image side surface of the fourth lens and the effective focal length f of the optical imaging system: 1.18 ≤ (f4 - f) / ∣R8 + R7∣ < 35.

[0013] Further, the following conditions are satisfied between the Abbe number V1 of the first lens and the Abbe number V4 of the fourth lens: 1 ≤ V1 / V4 < 3, and the following conditions are satisfied between the Abbe number V5 of the fifth lens and the Abbe number V7 of the seventh lens: 0 < V7 / V5 < 1.

[0014] Further, the following conditions are satisfied between the central thickness CT2 of the second lens on the optical axis, the central thickness CT3 of the third lens on the optical axis, and the air gap T23 between the second lens and the third lens on the optical axis: 3 < T23 / (CT2 - CT3) < 19. <​​​

[0016] Furthermore, the first lens has a positive optical power, and the effective focal length f1 of the first lens, the effective focal length f2 of the second lens, and the effective focal length f3 of the third lens satisfy: 1 < f3 / (f1 + f2) < 6.

[0017] Furthermore, the central thickness CT9 of the ninth lens on the optical axis and the distance BFL on the optical axis from the image side of the last lens of the optical imaging system to the imaging surface of the optical imaging system satisfy: 1 < BFL / CT9 < 4.

[0018] Furthermore, the radius of curvature of any side surface of any one of the first lens to the third lens satisfies: Rn > 0, where n takes values from 1, 2, 3, 4, 5, 6. Between the radius of curvature R1 of the object side surface of the first lens and the radius of curvature R2 of the image side surface of the first lens, R2 / R1 > 10. Between the radius of curvature R3 of the object side surface of the second lens, the radius of curvature R4 of the image side surface of the second lens, the radius of curvature R5 of the object side surface of the third lens, and the radius of curvature R6 of the image side surface of the third lens, R6 / R5 < R4 / R3 < 1.

[0019] Furthermore, the sum ∑CT of the thicknesses of the first lens to the ninth lens on the optical axis and the sum ∑AT of the air gaps on the optical axis between any two adjacent lenses among the first lens to the ninth lens satisfy: 1.7 < ∑CT / ∑AT < 2.5.

[0020] Furthermore, the distance TTL on the optical axis from the object side surface of the first lens to the imaging surface of the optical imaging system and the effective focal length f of the optical imaging system satisfy: TTL / f < 1.5. The half of the diagonal length ImgH of the effective pixel area on the imaging surface of the optical imaging system satisfies: ImgH > 5 mm. The maximum field angle FOV of the optical imaging system satisfies: FOV < 80°.

[0021] Furthermore, between the edge thickness ET8 of the eighth lens, the edge thickness ET9 of the ninth lens, the central thickness CT8 of the eighth lens on the optical axis, and the central thickness CT9 of the ninth lens on the optical axis, 1 < (ET9 + ET8) / (CT9 + CT8) < 2.1.

[0022] Furthermore, between the effective focal length f8 of the eighth lens and the effective focal length f9 of the ninth lens, -3 < f8 / f9 < 0. Between the radius of curvature R15 of the object side surface of the eighth lens and the radius of curvature R16 of the image side surface of the eighth lens, 0 < (R16 + R15) / (R16 - R15) < 5.

[0023] Further, the air gap T56 between the fifth lens and the sixth lens on the optical axis and the air gap T67 between the sixth lens and the seventh lens on the optical axis satisfy: 1 < T67 / T56 < 5.

[0024] Further, the Abbe number V4 of the fourth lens, the Abbe number V5 of the fifth lens, and the Abbe number V6 of the sixth lens satisfy: 25 < (V4 + V5 + V6) / 3 < 50.

[0025] Further, the effective focal length f1 of the first lens and the central thickness CT1 of the first lens satisfy: 3 < f1 / CT1 < 7.

[0026] Further, the eighth lens has a positive optical power; and / or the ninth lens has a negative optical power; and / or the object side surface of the first lens is convex, and the image side surface of the first lens is concave; and / or the object side surface of the second lens is convex, and the image side surface of the second lens is concave; and / or the object side surface of the third lens is convex, and the image side surface of the third lens is concave; and / or the object side surface of the eighth lens is convex, and the image side surface of the eighth lens is concave.

[0027] According to another aspect of the present invention, an optical imaging system is provided. The optical imaging system is a nine-lens imaging system, and sequentially includes, from the object side to the image side along the optical axis: a first lens with a positive optical power; a second lens with a negative optical power; a third lens with a negative optical power; a fourth lens with an optical power; a fifth lens with a positive optical power; a sixth lens with an optical power; a seventh lens with an optical power; an eighth lens with an optical power; a ninth lens with an optical power, and the object side surface of the ninth lens is convex; wherein, the entrance pupil diameter EPD of the optical imaging system and the effective focal length f of the optical imaging system satisfy: f / EPD < 1.7; the curvature radius R17 of the object side surface of the ninth lens and the curvature radius R18 of the image side surface of the ninth lens satisfy: 2.8 < R17 / R18 < 5; the Abbe number V1 of the first lens, the Abbe number V2 of the second lens, and the Abbe number V3 of the third lens satisfy: 28 < (V1 + V2 + V3) / 3 < 32.

[0028] Further, the object side surface of the fifth lens is concave, the image side surface of the fifth lens is convex, the curvature radius R9 of the object side surface of the fifth lens and the curvature radius R10 of the image side surface of the fifth lens satisfy: 0.5 < R9 / R10 < 4, and the curvature radius R9 of the object side surface of the fifth lens and the effective focal length f5 of the fifth lens satisfy: -1 < R9 / f5 < 0.

[0029] Furthermore, the object side surface of the sixth lens is convex, the image side surface of the sixth lens is concave, and the following conditions are satisfied between the radius of curvature R11 of the object side surface of the sixth lens and the radius of curvature R12 of the image side surface of the sixth lens: 0 < R11 / R12 < 4. The following condition is satisfied between the radius of curvature R11 of the object side surface of the sixth lens and the effective focal length f of the optical imaging system: 0 < R11 / f < 4.

[0030] Furthermore, the following condition is satisfied between the central thickness CT4 of the fourth lens on the optical axis and the central thickness CT5 of the fifth lens on the optical axis: 1 < CT5 / CT4 < 5

[0031] Furthermore, the following condition is satisfied between the central thickness CT1 of the first lens on the optical axis and the central thickness CTi of any one of the second to ninth lenses on the optical axis: CT1 / CTi > 1, where i takes values from 2, 3, 4, 5, 6, 7, 8, 9.

[0032] Furthermore, the fourth lens has a positive optical power. Both the object side surface and the image side surface of the fourth lens are convex. The following condition is satisfied between the effective focal length f4 of the fourth lens, the radius of curvature R7 of the object side surface of the fourth lens, the radius of curvature R8 of the image side surface of the fourth lens, and the effective focal length f of the optical imaging system: 1.18 ≤ (f4 - f) / ∣R8 + R7∣ < 35.

[0033] Furthermore, the following condition is satisfied between the Abbe number V1 of the first lens and the Abbe number V4 of the fourth lens: 1 ≤ V1 / V4 < 3. The following condition is satisfied between the Abbe number V5 of the fifth lens and the Abbe number V7 of the seventh lens: 0 < V7 / V5 < 1.

[0034] Furthermore, the following condition is satisfied between the central thickness CT2 of the second lens on the optical axis, the central thickness CT3 of the third lens on the optical axis, and the air gap T23 between the second lens and the third lens on the optical axis: 3 < T23 / (CT2 - CT3) < 19.

[0035] Furthermore, the following condition is satisfied between the central thickness CT6 of the sixth lens on the optical axis, the central thickness CT7 of the seventh lens on the optical axis, the central thickness CT8 of the eighth lens on the optical axis, the air gap T67 between the sixth lens and the seventh lens on the optical axis, and the air gap T78 between the seventh lens and the eighth lens on the optical axis: 2 < (CT6 + CT8 + CT7) / (T67 + T78) < 5.

[0036] Furthermore, the following condition is satisfied between the effective focal length f1 of the first lens, the effective focal length f2 of the second lens, and the effective focal length f3 of the third lens: 1 < f3 / (f1 + f2) < 6.

[0037] Further, the central thickness CT9 of the ninth lens on the optical axis and the distance BFL on the optical axis from the image side of the last lens of the optical imaging system to the imaging surface of the optical imaging system satisfy: 1 < BFL / CT9 < 4.

[0038] Further, the radius of curvature of any side surface of any one of the first lens to the third lens satisfies: Rn > 0, where n takes values from 1, 2, 3, 4, 5, 6. Between the radius of curvature R1 of the object side surface of the first lens and the radius of curvature R2 of the image side surface of the first lens, it satisfies: R2 / R1 > 10. Between the radius of curvature R3 of the object side surface of the second lens, the radius of curvature R4 of the image side surface of the second lens, the radius of curvature R5 of the object side surface of the third lens and the radius of curvature R6 of the image side surface of the third lens, it satisfies: R6 / R5 < R4 / R3 < 1.

[0039] Further, the sum ∑CT of the thicknesses of the first lens to the ninth lens on the optical axis and the sum ∑AT of the air gaps on the optical axis between any two adjacent lenses among the first lens to the ninth lens satisfy: 1.7 < ∑CT / ∑AT < 2.5.

[0040] Further, the distance TTL on the optical axis from the object side surface of the first lens to the imaging surface of the optical imaging system and the effective focal length f of the optical imaging system satisfy: TTL / f < 1.5. Half of the diagonal length ImgH of the effective pixel region on the imaging surface of the optical imaging system satisfies: ImgH > 5 mm. The maximum field angle FOV of the optical imaging system satisfies: FOV < 80°.

[0041] Further, between the edge thickness ET8 of the eighth lens, the edge thickness ET9 of the ninth lens, the central thickness CT8 of the eighth lens on the optical axis and the central thickness CT9 of the ninth lens on the optical axis, it satisfies: 1 < (ET9 + ET8) / (CT9 + CT8) < 2.1.

[0042] Further, between the effective focal length f8 of the eighth lens and the effective focal length f9 of the ninth lens, it satisfies: -3 < f8 / f9 < 0. Between the radius of curvature R15 of the object side surface of the eighth lens and the radius of curvature R16 of the image side surface of the eighth lens, it satisfies: 0 < (R16 + R15) / (R16 - R15) < 5.

[0043] Further, between the air gap T56 on the optical axis between the fifth lens and the sixth lens and the air gap T67 on the optical axis between the sixth lens and the seventh lens, it satisfies: 1 < T67 / T56 < 5.

[0044] Further, between the Abbe number V4 of the fourth lens, the Abbe number V5 of the fifth lens and the Abbe number V6 of the sixth lens, it satisfies: 25 < (V4 + V5 + V6) / 3 < 50.

[0045] Furthermore, the following condition is satisfied between the effective focal length f1 of the first lens and the central thickness CT1 of the first lens: 3 < f1 / CT1 < 7.

[0046] Furthermore, the eighth lens has a positive optical power; and / or the ninth lens has a negative optical power; and / or the object side surface of the first lens is convex, and the image side surface of the first lens is concave; and / or the object side surface of the second lens is convex, and the image side surface of the second lens is concave; and / or the object side surface of the third lens is convex, and the image side surface of the third lens is concave; and / or the object side surface of the eighth lens is convex, and the image side surface of the eighth lens is concave; and / or the image side surface of the ninth lens is concave.

[0047] Applying the technical solution of the present invention, the optical imaging system is a nine-lens imaging system, which sequentially includes a first lens with a positive optical power, a second lens with a negative optical power, a third lens with a negative optical power, a fourth lens with an optical power, a fifth lens with a positive optical power, a sixth lens with an optical power, a seventh lens with an optical power, an eighth lens with an optical power, and a ninth lens with an optical power along the optical axis from the object side to the image side, and the object side surface of the ninth lens is convex; wherein, the following condition is satisfied between the entrance pupil diameter EPD of the optical imaging system and the effective focal length f of the optical imaging system: f / EPD < 1.7; the following condition is satisfied between the curvature radius R17 of the object side surface of the ninth lens and the effective focal length f of the optical imaging system: 0 < R17 / f < 5; the following condition is satisfied among the Abbe number V1 of the first lens, the Abbe number V2 of the second lens, and the Abbe number V3 of the third lens: 28 < (V1 + V2 + V3) / 3 < 32.

[0048] By rationally allocating the focal power and surface shape of the optical imaging system, the workability of each lens can be ensured. Setting the second and third lenses to negative power, and the fifth lens to positive power, results in a smoother light path, balancing the aberrations generated by the first two lenses and improving the performance of the optical imaging system. Furthermore, controlling the ratio of the effective focal length of the optical imaging system to the entrance pupil diameter within a certain range helps increase the system's light throughput, improves the shutter speed in dark environments, and thus enhances the capture of details and the resolution of the optical imaging system. Properly constraining the ratio of the object-side radius of curvature of the ninth lens to the effective focal length of the optical imaging system promotes a smooth light transition, resulting in a smaller angle of incidence for the principal ray when incident on the imaging surface, thereby improving the resolution of the optical imaging system. Furthermore, controlling the Abbe numbers of the first, second, and third lenses within a reasonable range facilitates chromatic aberration correction in conjunction with the rear lens, thereby improving the imaging quality of the optical imaging system. By controlling the focal length, surface shape and the above parameters of the lens, the optical imaging system in this application has the advantages of large aperture and high resolution, so as to achieve the purpose of clear imaging in dark environments and improve the imaging effect of detail shooting. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0050] Figure 1 Schematic diagram of the structure of the optical imaging system of Example 1 of the present invention is shown;

[0051] Figures 2 to 5 Shown respectively Figure 1 The axial chromatic aberration curve, astigmatism curve, distortion curve and magnification chromatic aberration curve of the optical imaging system;

[0052] Figure 6 shows a schematic structural diagram of an optical imaging system according to Example 2 of the present invention;

[0053] Figures 7 to 10 Shown respectively Figure 6 The axial chromatic aberration curve, astigmatism curve, distortion curve and magnification chromatic aberration curve of the optical imaging system;

[0054] Figure 11 Schematic diagram of the structure of the optical imaging system of Example 3 of the present invention is shown;

[0055] Figures 12 to 15 Shown respectively Figure 11The axial chromatic aberration curve, astigmatism curve, distortion curve and magnification chromatic aberration curve of the optical imaging system;

[0056] Figure 16 Schematic diagram of the structure of the optical imaging system of Example 4 of the present invention is shown;

[0057] Figures 17 to 20 Shown respectively Figure 16 The axial chromatic aberration curve, astigmatism curve, distortion curve and magnification chromatic aberration curve of the optical imaging system;

[0058] Figure 21 Schematic diagram of the structure of the optical imaging system of Example 5 of the present invention is shown;

[0059] Figures 22 to 25 Shown respectively Figure 21 The axial chromatic aberration curve, astigmatism curve, distortion curve and magnification chromatic aberration curve of the optical imaging system;

[0060] Figure 26 Schematic diagram of the structure of the optical imaging system of Example 6 of the present invention is shown;

[0061] Figures 27 to 30 Shown respectively Figure 26 The axial chromatic aberration curve, astigmatism curve, distortion curve and magnification chromatic aberration curve of the optical imaging system.

[0062] The above drawings include the following reference numerals:

[0063] STO, aperture; E1, first lens; S1, object-side surface of the first lens; S2, image-side surface of the first lens; E2, second lens; S3, object-side surface of the second lens; S4, image-side surface of the second lens; E3, third lens; S5, object-side surface of the third lens; S6, image-side surface of the third lens; E4, fourth lens; S7, object-side surface of the fourth lens; S8, image-side surface of the fourth lens; E5, fifth lens; S9, object-side surface of the fifth lens; S10, image-side surface of the fifth lens; E6, fourth lens Six lenses; S11, object-side surface of the sixth lens; S12, image-side surface of the sixth lens; E7, seventh lens; S13, object-side surface of the seventh lens; S14, image-side surface of the seventh lens; E8, eighth lens; S15, object-side surface of the eighth lens; S16, image-side surface of the eighth lens; E9, ninth lens; S17, object-side surface of the ninth lens; S18, image-side surface of the ninth lens; E10, filter; S19, object-side surface of the filter; S20, image-side surface of the filter; S21, imaging surface. DETAILED DESCRIPTION

[0064] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0065] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by ordinary technicians in the technical field to which this application belongs.

[0066] In the present invention, unless otherwise specified, the directional words used, such as "up, down, top, bottom", usually refer to the directions shown in the drawings, or to the components themselves in the vertical, perpendicular or gravity direction; similarly, for ease of understanding and description, "inside and outside" refer to the inside and outside relative to the outline of each component itself, but the above directional words are not used to limit the present invention.

[0067] It should be noted that in this specification, the terms "first," "second," "third," etc., are used solely to distinguish one feature from another and do not limit the features. Thus, the first lens discussed below could also be referred to as the second lens or the third lens without departing from the teachings of this application.

[0068] In the drawings, the thickness, size, and shape of the lenses are slightly exaggerated for ease of illustration. Specifically, the shapes of the spherical and aspherical surfaces shown in the drawings are provided by way of example. That is, the shapes of the spherical and aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustration only and are not drawn strictly to scale.

[0069] In this article, the paraxial area refers to the area near the optical axis. If the lens surface is convex and the position of the convex surface is not defined, it means that the lens surface is convex at least in the paraxial area; if the lens surface is concave and the position of the concave surface is not defined, it means that the lens surface is concave at least in the paraxial area. The judgment of the surface shape in the paraxial area can be based on the judgment method of ordinary knowledge in this field, and the positive and negative R value (R refers to the radius of curvature of the paraxial area, usually refers to the R value on the lens database (lens data) in the optical software) is used to judge the convexity and concavity. For the object side, when the R value is positive, it is judged to be convex, and when the R value is negative, it is judged to be concave; for the image side, when the R value is positive, it is judged to be concave, and when the R value is negative, it is judged to be convex.

[0070] In order to solve the problem in the prior art that it is difficult to achieve both large aperture and high resolution in optical imaging systems, the present invention provides an optical imaging system.

[0071] Example 1

[0072] like Figures 1 to 30As shown, the optical imaging system is a nine-lens imaging system, which sequentially includes, from the object side to the image side along the optical axis, a first lens with a positive optical power, a second lens with a negative optical power, a third lens with a negative optical power, a fourth lens with an optical power, a fifth lens with a positive optical power, a sixth lens with an optical power, a seventh lens with an optical power, an eighth lens with an optical power, and a ninth lens with an optical power. The object side surface of the ninth lens is convex. Among them, the relationship between the entrance pupil diameter EPD of the optical imaging system and the effective focal length f of the optical imaging system satisfies: f / EPD < 1.7; the relationship between the curvature radius R17 of the object side surface of the ninth lens and the effective focal length f of the optical imaging system satisfies: 0 < R17 / f < 5; the relationship between the Abbe number V1 of the first lens, the Abbe number V2 of the second lens, and the Abbe number V3 of the third lens satisfies: 28 < (V1 + V2 + V3) / 3 < 32.

[0073] By reasonably distributing the optical power and surface shape of the optical imaging system, good processability of each lens can be ensured. Setting the first lens to have a positive optical power, the second and third lenses to have negative optical powers, and the fifth lens to have a positive optical power makes the light path relatively gentle, which is beneficial to balancing the aberration generated by the first three lenses and improving the performance of the optical imaging system. At the same time, controlling the ratio of the effective focal length of the optical imaging system to the entrance pupil diameter of the optical imaging system within a certain range is beneficial to increasing the light passing amount of the optical imaging system, improving the shutter speed of the optical imaging system in a dark environment, and then enhancing the shooting effect of details and improving the resolution of the optical imaging system. Reasonably restricting the ratio of the curvature radius of the object side surface of the ninth lens to the effective focal length of the optical imaging system is beneficial to the gentle transition of light, making the chief ray have a smaller incident angle when incident on the imaging surface and improving the resolution of the optical imaging system. At the same time, controlling the Abbe numbers of the first, second, and third lenses within a reasonable range is beneficial to cooperating with the rear lenses to achieve the purpose of correcting chromatic aberration and improving the imaging quality of the optical imaging system. By controlling the optical power, surface shape of the lens, and the above parameters, the optical imaging system in this application simultaneously has the advantages of a large aperture and high resolution, so as to achieve the purpose of clear imaging in a dark environment and improve the imaging effect of detail shooting.

[0074] Preferably, the relationship between the entrance pupil diameter EPD of the optical imaging system and the effective focal length f of the optical imaging system satisfies: 1.3 < f / EPD < 1.5; the relationship between the curvature radius R17 of the object side surface of the ninth lens and the effective focal length f of the optical imaging system satisfies: 0 < R17 / f < 2; the relationship between the Abbe number V1 of the first lens, the Abbe number V2 of the second lens, and the Abbe number V3 of the third lens satisfies: 30 < (V1 + V2 + V3) / 3 < 32.

[0075] In this embodiment, the image side of the ninth lens is concave, and the following relationship is satisfied between the curvature radius R17 of the object side of the ninth lens and the curvature radius R18 of the image side of the ninth lens: 2.8 < R17 / R18 < 5. By setting the image side of the ninth lens to be concave, it is beneficial to correct field curvature. At the same time, reasonably controlling the ratio of the curvature radius of the object side and the curvature radius of the image side of the ninth lens is beneficial to reducing the surface sensitivity caused by the surface shape difference between the object side and the image side of the ninth lens and improving the processability of the ninth lens. Preferably, 3.2 < R17 / R18 < 4.

[0076] In this embodiment, the object side of the fifth lens is concave, the image side of the fifth lens is convex, and the following relationship is satisfied between the curvature radius R9 of the object side of the fifth lens and the curvature radius R10 of the image side of the fifth lens: 0.5 < R9 / R10 < 4. The following relationship is satisfied between the curvature radius R9 of the object side of the fifth lens and the effective focal length f5 of the fifth lens: -1 < R9 / f5 < 0. By controlling R9 / R10 and R9 / f5 within a reasonable range, it is beneficial to ensure that the fifth lens has a reasonable optical power, while reducing the angle between the chief ray and the optical axis when it enters the imaging surface and improving the illuminance of the imaging surface. Preferably, 0.9 < R9 / R10 < 2, -0.5 < R9 / f5 < 0.

[0077] In this embodiment, the object side of the sixth lens is convex, the image side of the sixth lens is concave, and the following relationship is satisfied between the curvature radius R11 of the object side of the sixth lens and the curvature radius R12 of the image side of the sixth lens: 0 < R11 / R12 < 4. The following relationship is satisfied between the curvature radius R11 of the object side of the sixth lens and the effective focal length f of the optical imaging system: 0 < R11 / f < 4. By setting the object side of the sixth lens to be convex and the image side of the sixth lens to be concave, the sixth lens is combined with the fifth lens to balance aberrations. At the same time, reasonably controlling the ratio of the curvature radius of the object side and the image side of the sixth lens is beneficial to ensuring that the deflection angle of the light ray after the fifth lens and the sixth lens is not too large, so as to reduce the processing difficulty caused by excessive light ray jitter. Preferably, 0.5 < R11 / R12 < 2, 1 < R11 / f < 2.5.

[0078] In this embodiment, the following relationship is satisfied between the central thickness CT4 of the fourth lens on the optical axis and the central thickness CT5 of the fifth lens on the optical axis: 1 < CT5 / CT4 < 5. By restricting the ratio of the central thicknesses of the fourth lens and the fifth lens on the optical axis, it is beneficial to reducing the sensitivity of the optical thicknesses of the fourth lens and the fifth lens and facilitating mass production. Preferably, 1.8 < CT5 / CT4 < 4.

[0079] In this embodiment, the central thickness CT1 of the first lens on the optical axis and the central thickness CTi of any one of the second lens to the ninth lens on the optical axis satisfy: CT1 / CTi > 1, where i takes values from 2, 3, 4, 5, 6, 7, 8, 9. Among the multiple lenses, the first lens has the largest thickness. Increasing the thickness of the first lens is beneficial to weakening the intensity of ghost image energy generated by internal reflection in the first lens and reducing the tilt sensitivity of the first lens, which is beneficial to mass production.

[0080] In this embodiment, the fourth lens has a positive optical power. Both the object side and the image side of the fourth lens are convex surfaces. The effective focal length f4 of the fourth lens, the curvature radius R7 of the object side of the fourth lens, the curvature radius R8 of the image side of the fourth lens, and the effective focal length f of the optical imaging system satisfy: 1.18 ≤ (f4 - f) / ∣R8 + R7∣ < 35. The fourth lens having a positive optical power can cooperate with the negative optical powers of the second lens and the third lens to correct aberrations. Both the object side and the image side of the fourth lens being convex surfaces are beneficial to correcting field curvature and distortion, improving the imaging quality of the optical imaging system, and at the same time ensuring the processability of the surface shape of the fourth lens. Preferably, 1.18 ≤ (f4 - f) / ∣R8 + R7∣ < 32.

[0081] In this embodiment, the Abbe number V1 of the first lens and the Abbe number V4 of the fourth lens satisfy: 1 ≤ V1 / V4 < 3, and the Abbe number V5 of the fifth lens and the Abbe number V7 of the seventh lens satisfy: < 0 < V7 / V5 < 1. By controlling the ratio of the Abbe numbers of the first lens and the fourth lens, and controlling the ratio of the Abbe numbers of the seventh lens and the fifth lens, it helps to improve the chromatic aberration correction ability of the optical imaging system and improve the imaging quality of the optical imaging system. Preferably, 1 ≤ V1 / V4 < 2.9, 0.4 < V7 / V5 < 0.8.

[0082] In this embodiment, the central thickness CT2 of the second lens on the optical axis, the central thickness CT3 of the third lens on the optical axis, and the air gap T23 between the second lens and the third lens on the optical axis satisfy: 3 < T23 / (CT2 - CT3) < 19. Reasonably allocating the central thicknesses of the second lens and the third lens on the optical axis and the air gap between the two lenses can ensure the processing and assembly characteristics, avoid problems such as interference between the front and rear lenses during the assembly process due to too small a gap, and is beneficial to improving the stability of the optical imaging system. Preferably, 3.2 < T23 / (CT2 - CT3) < 18.5.

[0083] In this embodiment, the central thickness CT6 of the sixth lens on the optical axis, the central thickness CT7 of the seventh lens on the optical axis, the central thickness CT8 of the eighth lens on the optical axis, the air gap T67 between the sixth lens and the seventh lens on the optical axis, and the air gap T78 between the seventh lens and the eighth lens on the optical axis satisfy: 2 < (CT6 + CT8 + CT7) / (T67 + T78) < 5. Reasonably controlling the ratio of the central thicknesses of the sixth, seventh, and eighth lenses on the optical axis to the sum of the air gaps of the three lenses on the optical axis within a certain range is beneficial to slowing down the light deflection, adjusting the field curvature of the optical imaging system, reducing the sensitivity, and thus obtaining better imaging quality. Preferably, 2.5 < (CT6 + CT8 + CT7) / (T67 + T78) < 4.

[0084] In this embodiment, the first lens has a positive optical power, and the effective focal length f1 of the first lens, the effective focal length f2 of the second lens, and the effective focal length f3 of the third lens satisfy: 1 < f3 / (f1 + f2) < 6. Reasonably distributing the effective focal lengths of the first lens to the third lens ensures that the optical power borne by the lenses in the optical imaging system does not concentrate on one or two of them, avoids large fluctuations in the optical path, and also effectively avoids the generation of lens shapes that are difficult to process. Preferably, 2.5 < f3 / (f1 + f2) < 4.5.

[0085] In this embodiment, the central thickness CT9 of the ninth lens on the optical axis and the distance BFL on the optical axis from the image side of the last lens of the optical imaging system to the imaging plane of the optical imaging system satisfy: 1 < BFL / CT9 < 4. By restricting BFL / CT9 within a reasonable range, it is beneficial to controlling the total length of the optical imaging system and facilitating the miniaturization of the optical imaging system. Preferably, 1.2 < BFL / CT9 < 3.8.

[0086] In this embodiment, the radius of curvature of any side surface of any one of the first lens to the third lens satisfies: Rn > 0, where n takes values from 1, 2, 3, 4, 5, 6. The radius of curvature R1 of the object side surface of the first lens and the radius of curvature R2 of the image side surface of the first lens satisfy: R2 / R1 > 10. The radius of curvature R3 of the object side surface of the second lens, the radius of curvature R4 of the image side surface of the second lens, the radius of curvature R5 of the object side surface of the third lens, and the radius of curvature R6 of the image side surface of the third lens satisfy: R6 / R5 < R4 / R3 < 1. By controlling R2 / R1, R6 / R5, and R4 / R3 within a reasonable range, reasonably distributing the radii of curvature of the first lens to the third lens, ensuring the uniformity of the lens surface shape, and reducing the processing difficulty of the first lens to the third lens. Preferably, 11 < R2 / R1 < 15, 0.3 < R6 / R5 < R4 / R3 < 0.8.

[0087] In this embodiment, the sum ∑CT of the thicknesses of the first lens to the ninth lens on the optical axis respectively, and the sum ∑AT of the air gaps on the optical axis between any two adjacent lenses among the first lens to the ninth lens satisfy: 1.7 < ∑CT / ∑AT < 2.5. By restricting the range of ∑CT / ∑AT, the first lens to the ninth lens are evenly distributed within the optical imaging system, which is conducive to the assembly between the lenses and reduces the assembly difficulty of the lenses. Preferably, 1.75 < ∑CT / ∑AT < 2.2.

[0088] In this embodiment, the distance TTL on the optical axis from the object side surface of the first lens to the imaging surface of the optical imaging system and the effective focal length f of the optical imaging system satisfy: TTL / f < 1.5, half ImgH of the diagonal length of the effective pixel region on the imaging surface of the optical imaging system satisfies: ImgH > 5 mm, and the maximum field angle FOV of the optical imaging system satisfies: FOV < 80°. By controlling TTL / f and FOV within reasonable ranges, it is conducive to achieving a larger field angle within a certain total optical length to obtain a larger shooting range. At the same time, by controlling ImgH within a reasonable range, it is conducive to improving the resolution of the optical imaging system and increasing the imaging quality of the optical imaging system. Preferably, 1 < TTL / f < 1.4, 5 mm < ImgH < 7 mm, 60° < FOV < 80°.

[0089] In this embodiment, the edge thickness ET8 of the eighth lens, the edge thickness ET9 of the ninth lens, the central thickness CT8 of the eighth lens on the optical axis, and the central thickness CT9 of the ninth lens on the optical axis satisfy: 1 < (ET9 + ET8) / (CT9 + CT8) < 2.1. By controlling (ET9 + ET8) / (CT9 + CT8) within a reasonable range, the lens is easy to be injection molded, improving the processability of the optical imaging system, and at the same time ensuring that the optical imaging system has good imaging quality. Preferably, 1.2 < (ET9 + ET8) / (CT9 + CT8) < 1.9.

[0090] In this embodiment, the effective focal length f8 of the eighth lens and the effective focal length f9 of the ninth lens satisfy: -3 < f8 / f9 < 0, and the curvature radius R15 of the object side surface of the eighth lens and the curvature radius R16 of the image side surface of the eighth lens satisfy: 0 < (R16 + R15) / (R16 - R15) < 5. By controlling f8 / f9 within a reasonable range, the eighth lens and the ninth lens have opposite optical powers, which is conducive to balancing aberrations. At the same time, by controlling (R16 + R15) / (R16 - R15), it is ensured that the surface shape of the eighth lens is easy to process and reduces the processing difficulty of the eighth lens. Preferably, 1.5 < (R16 + R15) / (R16 - R15) < 3.

[0091] In this embodiment, the air gap T56 between the fifth lens and the sixth lens on the optical axis and the air gap T67 between the sixth lens and the seventh lens on the optical axis satisfy: 1 < T67 / T56 < 5. By controlling T67 / T56 within a reasonable range, the size of the optical imaging system can be effectively reduced, avoiding the optical imaging system from being too large in volume, and at the same time reducing the assembly difficulty of the lenses, so as to achieve a higher space utilization rate. Preferably, 2 < T67 / T56 < 4.

[0092] In this embodiment, the Abbe number V4 of the fourth lens, the Abbe number V5 of the fifth lens, and the Abbe number V6 of the sixth lens satisfy: 25 < (V4 + V5 + V6) / 3 < 50. Controlling the Abbe numbers of the fourth lens, the fifth lens, and the sixth lens within a reasonable range helps to reduce chromatic aberration and improve the resolution of the optical imaging system. Preferably, 30 < (V4 + V5 + V6) / 3 < 48.

[0093] In this embodiment, the ratio of the effective focal length f1 of the first lens to the central thickness CT1 of the first lens satisfies: 3 < f1 / CT1 < 7. By controlling the ratio of the effective focal length and the central thickness of the first lens within a reasonable range, it is beneficial to limit the curvature radius of the first lens, and then control the shape of the first lens, improving the processability of the first lens. Preferably, 4 < f1 / CT1 < 6.

[0094] In this embodiment, the eighth lens has a positive optical power; and / or the ninth lens has a negative optical power; and / or the object side of the first lens is convex and the image side of the first lens is concave; and / or the object side of the second lens is convex and the image side of the second lens is concave; and / or the object side of the third lens is convex and the image side of the third lens is concave; and / or the object side of the eighth lens is convex and the image side of the eighth lens is concave. Reasonably distributing the optical power and surface shape of the lenses is beneficial to better balance the aberrations of the optical imaging system and is also beneficial to improving the resolution of the system.

[0095] Embodiment 2

[0096] As Figures 1 to 30As shown in the figure, the optical imaging system is a nine-lens imaging system, which sequentially includes, from the object side to the image side along the optical axis, a first lens with positive optical power, a second lens with negative optical power, a third lens with negative optical power, a fourth lens with optical power, a fifth lens with positive optical power, a sixth lens with optical power, a seventh lens with optical power, an eighth lens with optical power, and a ninth lens with optical power. The object side surface of the ninth lens is convex. Among them, the entrance pupil diameter EPD of the optical imaging system and the effective focal length f of the optical imaging system satisfy: f / EPD < 1.7; the curvature radius R17 of the object side surface of the ninth lens and the curvature radius R18 of the image side surface of the ninth lens satisfy: 2.8 < R17 / R18 < 5; the Abbe number V1 of the first lens, the Abbe number V2 of the second lens, and the Abbe number V3 of the third lens satisfy: 28 < (V1 + V2 + V3) / 3 < 32.

[0097] By reasonably distributing the optical power and surface shape of the optical imaging system, good processability of each lens can be ensured. Setting the first lens to have positive optical power, the second and third lenses to have negative optical power, and the fifth lens to have positive optical power makes the light path relatively gentle, which is beneficial to balancing the aberration generated by the first three lenses and improving the performance of the optical imaging system. At the same time, controlling the ratio of the effective focal length of the optical imaging system to the entrance pupil diameter of the optical imaging system within a certain range is beneficial to increasing the light transmission of the optical imaging system, improving the shutter speed of the optical imaging system in a dark environment, and then enhancing the shooting effect of details and improving the resolution of the optical imaging system. By setting the image side surface of the ninth lens to be concave, it is beneficial to correct field curvature. At the same time, reasonably controlling the ratio of the curvature radius of the object side surface and the curvature radius of the image side surface of the ninth lens is beneficial to reducing the surface shape sensitivity caused by the surface shape difference between the object side surface and the image side surface of the ninth lens and improving the processability of the ninth lens. At the same time, controlling the Abbe numbers of the first, second, and third lenses within a reasonable range is beneficial to cooperating with the rear lenses to achieve the purpose of correcting chromatic aberration and improving the imaging quality of the optical imaging system. By controlling the optical power, surface shape, and the above parameters of the lens, the optical imaging system in this application has the advantages of a large aperture and high resolution at the same time, so as to achieve the purpose of clear imaging in a dark environment and improve the imaging effect of detail shooting.

[0098] Preferably, the entrance pupil diameter EPD of the optical imaging system and the effective focal length f of the optical imaging system satisfy: 1.3 < f / EPD < 1.5; the curvature radius R17 of the object side surface of the ninth lens and the curvature radius R18 of the image side surface of the ninth lens satisfy: 3.2 < R17 / R18 < 4; the Abbe number V1 of the first lens, the Abbe number V2 of the second lens, and the Abbe number V3 of the third lens satisfy: 30 < (V1 + V2 + V3) / 3 < 32.

[0099] In this embodiment, the object side of the fifth lens is concave, and the image side of the fifth lens is convex. The relationship between the radius of curvature R9 of the object side of the fifth lens and the radius of curvature R10 of the image side of the fifth lens satisfies: 0.5 < R9 / R10 < 4. The relationship between the radius of curvature R9 of the object side of the fifth lens and the effective focal length f5 of the fifth lens satisfies: -1 < R9 / f5 < 0. By controlling R9 / R10 and R9 / f5 within a reasonable range, it is beneficial to ensure that the fifth lens has a reasonable optical power, while reducing the angle between the chief ray and the optical axis when it enters the imaging surface, and improving the illuminance of the imaging surface. Preferably, 0.9 < R9 / R10 < 2, -0.5 < R9 / f5 < 0.

[0100] In this embodiment, the object side of the sixth lens is convex, and the image side of the sixth lens is concave. The relationship between the radius of curvature R11 of the object side of the sixth lens and the radius of curvature R12 of the image side of the sixth lens satisfies: 0 < R11 / R12 < 4. The relationship between the radius of curvature R11 of the object side of the sixth lens and the effective focal length f of the optical imaging system satisfies: 0 < R11 / f < 4. By setting the object side of the sixth lens to be convex and the image side of the sixth lens to be concave, the sixth lens and the fifth lens cooperate to balance the aberration. At the same time, reasonably controlling the ratio of the radius of curvature of the object side to the image side of the sixth lens is beneficial to ensure that the deflection angle of the light after the fifth lens and the sixth lens is not too large, so as to reduce the processing difficulty caused by excessive light jitter. Preferably, 0.5 < R11 / R12 < 2, 1 < R11 / f < 2.5.

[0101] In this embodiment, the relationship between the central thickness CT4 of the fourth lens on the optical axis and the central thickness CT5 of the fifth lens on the optical axis satisfies: 1 < CT5 / CT4 < 5. By restricting the ratio of the central thicknesses of the fourth lens and the fifth lens on the optical axis, it is beneficial to reduce the sensitivity of the optical thicknesses of the fourth lens and the fifth lens, which is beneficial to mass production. Preferably, 1.8 < CT5 / CT4 < 4.

[0102] In this embodiment, the relationship between the central thickness CT1 of the first lens on the optical axis and the central thickness CTi of any lens from the second lens to the ninth lens on the optical axis satisfies: CT1 / CTi > 1, where i takes values from 2, 3, 4, 5, 6, 7, 8, 9. Among the multiple lenses, the first lens has the largest thickness. Increasing the thickness of the first lens is beneficial to weakening the intensity of the ghost image energy generated by internal reflection in the first lens and reducing the tilt sensitivity of the first lens, which is beneficial to mass production.

[0103] In this embodiment, the fourth lens has a positive optical power. Both the object side surface and the image side surface of the fourth lens are convex surfaces. The effective focal length f4 of the fourth lens, the radius of curvature R7 of the object side surface of the fourth lens, the radius of curvature R8 of the image side surface of the fourth lens, and the effective focal length f of the optical imaging system satisfy: 1.18 ≤ (f4 - f) / |R8 + R7| < 35. The fourth lens having a positive optical power can cooperate with the negative optical powers of the second lens and the third lens to correct aberrations. Both the object side surface and the image side surface of the fourth lens being convex surfaces are beneficial for correcting field curvature and distortion, improving the imaging quality of the optical imaging system, and at the same time ensuring the processability of the surface shape of the fourth lens. Preferably, 1.18 ≤ (f4 - f) / |R8 + R7| < 32.

[0104] In this embodiment, the Abbe number V1 of the first lens and the Abbe number V4 of the fourth lens satisfy: 1 ≤ V1 / V4 < 3. The Abbe number V5 of the fifth lens and the Abbe number V7 of the seventh lens satisfy: 0 < V7 / V5 < 1. By controlling the ratio of the Abbe numbers of the first lens and the fourth lens, and controlling the ratio of the Abbe numbers of the seventh lens and the fifth lens, it helps to improve the chromatic aberration correction ability of the optical imaging system and improve the imaging quality of the optical imaging system. Preferably, 1 ≤ V1 / V4 < 2.9, 0.4 < V7 / V5 < 0.8.

[0105] In this embodiment, the central thickness CT2 of the second lens on the optical axis, the central thickness CT3 of the third lens on the optical axis, and the air gap T23 between the second lens and the third lens on the optical axis satisfy: 3 < T23 / (CT2 - CT3) < 19. Reasonably allocating the central thicknesses of the second lens and the third lens on the optical axis and the air gap between the two lenses can ensure the processing and assembly characteristics, avoid problems such as interference between the front and rear lenses during the assembly process due to too small a gap, and is beneficial for improving the stability of the optical imaging system. Preferably, 3.2 < T23 / (CT2 - CT3) < 18.5.

[0106] In this embodiment, the central thickness CT6 of the sixth lens on the optical axis, the central thickness CT7 of the seventh lens on the optical axis, the central thickness CT8 of the eighth lens on the optical axis, the air gap T67 between the sixth lens and the seventh lens on the optical axis, and the air gap T78 between the seventh lens and the eighth lens on the optical axis satisfy: 2 < (CT6 + CT8 + CT7) / (T67 + T78) < 5. Reasonably controlling the ratio of the central thicknesses of the sixth lens, the seventh lens, and the eighth lens on the optical axis to the sum of the air gaps of the three lenses on the optical axis within a certain range is beneficial for slowing down the light deflection, adjusting the field curvature of the optical imaging system, reducing the sensitivity, and thus obtaining better imaging quality. Preferably, 2.5 < (CT6 + CT8 + CT7) / (T67 + T78) < 4.

[0107] In this embodiment, the first lens has a positive optical power, and the effective focal length f1 of the first lens, the effective focal length f2 of the second lens, and the effective focal length f3 of the third lens satisfy: 1 < f3 / (f1 + f2) < 6. By reasonably distributing the effective focal lengths of the first lens to the third lens, the optical power borne by the lenses in the optical imaging system will not be concentrated on one or two of them, avoiding large fluctuations in the optical path and effectively avoiding the generation of lens shapes that are difficult to process. Preferably, 2.5 < f3 / (f1 + f2) < 4.5.

[0108] In this embodiment, the central thickness CT9 of the ninth lens on the optical axis and the distance BFL on the optical axis from the image side of the last lens of the optical imaging system to the imaging surface of the optical imaging system satisfy: 1 < BFL / CT9 < 4. By restricting BFL / CT9 within a reasonable range, it is beneficial to control the total length of the optical imaging system and is beneficial to the miniaturization of the optical imaging system. Preferably, 1.2 < BFL / CT9 < 3.8.

[0109] In this embodiment, the radius of curvature of any side surface of any one of the first lens to the third lens satisfies: Rn > 0, where n takes values from 1, 2, 3, 4, 5, 6. The radius of curvature R1 of the object side surface of the first lens and the radius of curvature R2 of the image side surface of the first lens satisfy: R2 / R1 > 10. The radius of curvature R3 of the object side surface of the second lens, the radius of curvature R4 of the image side surface of the second lens, the radius of curvature R5 of the object side surface of the third lens, and the radius of curvature R6 of the image side surface of the third lens satisfy: R6 / R5 < R4 / R3 < 1. By controlling R2 / R1, R6 / R5, and R4 / R3 within reasonable ranges, the radii of curvature of the first lens to the third lens are reasonably distributed, ensuring the uniformity of the lens surface shape and reducing the processing difficulty of the first lens to the third lens. Preferably, 11 < R2 / R1 < 15, 0.3 < R6 / R5 < R4 / R3 < 0.8.

[0110] In this embodiment, the total sum ∑CT of the thicknesses of the first lens to the ninth lens on the optical axis and the total sum ∑AT of the air gaps on the optical axis between any two adjacent lenses among the first lens to the ninth lens satisfy: 1.7 < ∑CT / ∑AT < 2.5. By restricting the range of ∑CT / ∑AT, the first lens to the ninth lens are evenly distributed in the optical imaging system, which is beneficial to the assembly between the lenses and reduces the assembly difficulty of the lenses. Preferably, 1.75 < ∑CT / ∑AT < 2.2.

[0111] In this embodiment, the distance TTL from the object side surface of the first lens to the imaging surface of the optical imaging system on the optical axis and the effective focal length f of the optical imaging system satisfy: TTL / f < 1.5. Half of the diagonal length ImgH of the effective pixel region on the imaging surface of the optical imaging system satisfies: ImgH > 5 mm. The maximum field of view FOV of the optical imaging system satisfies: FOV < 80°. By controlling TTL / f and FOV within reasonable ranges, it is beneficial to achieve a larger field of view within a certain total optical length to obtain a larger shooting range. At the same time, by controlling ImgH within a reasonable range, it is beneficial to improve the resolution of the optical imaging system and increase the imaging quality of the optical imaging system. Preferably, 1 < TTL / f < 1.4, 5 mm < ImgH < 7 mm, 60° < FOV < 80°.

[0112] In this embodiment, the edge thickness ET8 of the eighth lens, the edge thickness ET9 of the ninth lens, the central thickness CT8 of the eighth lens on the optical axis, and the central thickness CT9 of the ninth lens on the optical axis satisfy: 1 < (ET9 + ET8) / (CT9 + CT8) < 2.1. By controlling (ET9 + ET8) / (CT9 + CT8) within a reasonable range, it is easy to injection mold the lens, improving the processability of the optical imaging system, and at the same time ensuring that the optical imaging system has good imaging quality. Preferably, 1.2 < (ET9 + ET8) / (CT9 + CT8) < 1.9.

[0113] In this embodiment, the effective focal length f8 of the eighth lens and the effective focal length f9 of the ninth lens satisfy: -3 < f8 / f9 < 0. The radius of curvature R15 of the object side surface of the eighth lens and the radius of curvature R16 of the image side surface of the eighth lens satisfy: 0 < (R16 + R15) / (R16 - R15) < 5. By controlling f8 / f9 within a reasonable range, the eighth lens and the ninth lens have opposite optical powers, which is beneficial to balancing aberrations. At the same time, by controlling (R16 + R15) / (R16 - R15), it is ensured that the surface shape of the eighth lens is easy to process and the processing difficulty of the eighth lens is reduced. Preferably, 1.5 < (R16 + R15) / (R16 - R15) < 3.

[0114] In this embodiment, the air gap T56 between the fifth lens and the sixth lens on the optical axis and the air gap T67 between the sixth lens and the seventh lens on the optical axis satisfy: 1 < T67 / T56 < 5. By controlling T67 / T56 within a reasonable range, the size of the optical imaging system can be effectively reduced, avoiding the optical imaging system from being too large in volume. At the same time, the assembly difficulty of the lens is reduced to achieve a higher space utilization rate. Preferably, 2 < T67 / T56 < 4.

[0115] In this embodiment, the Abbe numbers V4 of the fourth lens, V5 of the fifth lens, and V6 of the sixth lens satisfy: 25 < (V4 + V5 + V6) / 3 < 50. Controlling the Abbe numbers of the fourth lens, the fifth lens, and the sixth lens within a reasonable range helps to reduce chromatic aberration and improve the resolution of the optical imaging system. Preferably, 30 < (V4 + V5 + V6) / 3 < 48.

[0116] In this embodiment, the effective focal length f1 of the first lens and the central thickness CT1 of the first lens satisfy: 3 < f1 / CT1 < 7. By controlling the ratio of the effective focal length to the central thickness of the first lens within a reasonable range, it is beneficial to limit the radius of curvature of the first lens, thereby controlling the shape of the first lens and improving the processability of the first lens. Preferably, 4 < f1 / CT1 < 6.

[0117] In this embodiment, the eighth lens has a positive optical power; and / or the ninth lens has a negative optical power; and / or the object side of the first lens is convex, and the image side of the first lens is concave; and / or the object side of the second lens is convex, and the image side of the second lens is concave; and / or the object side of the third lens is convex, and the image side of the third lens is concave; and / or the object side of the eighth lens is convex, and the image side of the eighth lens is concave; and / or the image side of the ninth lens is concave. Reasonably distributing the optical power and surface shape of the lenses is beneficial for the optical imaging system to better balance aberrations and is also beneficial for improving the resolution of the system.

[0118] Optionally, the above optical imaging system may further include a filter for correcting color deviation and / or a protective glass for protecting the photosensitive element located on the imaging surface.

[0119] The optical imaging system in this application can use multiple lenses, such as the nine lenses described above. By reasonably distributing the optical power, surface shape, central thickness of each lens, and the on-axis distance between each lens, etc., the imaging quality of the optical imaging system can be effectively increased, the sensitivity of the optical imaging system can be reduced, and the processability of the optical imaging system can be improved, making the optical imaging system more conducive to production and processing and applicable to portable electronic devices such as smartphones.

[0120] In this application, at least one of the lens surfaces of each lens is an aspherical surface. The characteristics of an aspherical lens are that the curvature changes continuously from the center of the lens to the periphery of the lens. Different from a spherical lens with a constant curvature from the center of the lens to the periphery of the lens, an aspherical lens has better radius of curvature characteristics and has the advantages of improving distortion aberration and improving astigmatism aberration. After using an aspherical lens, it is possible to eliminate the aberrations that occur during imaging as much as possible, thereby improving the imaging quality.

[0121] However, those skilled in the art will appreciate that the number of lenses comprising the optical imaging system can be varied to achieve the various results and advantages described herein without departing from the technical solutions claimed herein. For example, although nine lenses are described as an example in the embodiments, the optical imaging system is not limited to nine lenses. If desired, the optical imaging system may also include other numbers of lenses.

[0122] The following further describes examples of specific surface shapes and parameters of the optical imaging system applicable to the above-mentioned embodiments with reference to the accompanying drawings.

[0123] It should be noted that any one of the following examples 1 to 6 is applicable to all embodiments of the present application.

[0124] Example 1

[0125] like Figures 1 to 5 As shown, the optical imaging system of Example 1 of the present application is described. Figure 1 A schematic structural diagram of the optical imaging system of Example 1 is shown.

[0126] like Figure 1 As shown, the optical imaging system includes, from the object side to the image side, an aperture STO, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, an eighth lens E8, a ninth lens E9, a filter E10 and an imaging surface S21.

[0127] The first lens E1 has positive focal power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens E2 has negative focal power, with its object-side surface S3 being convex and its image-side surface S4 being concave. The third lens E3 has negative focal power, with its object-side surface S5 being convex and its image-side surface S6 being concave. The fourth lens E4 has positive focal power, with its object-side surface S7 being convex and its image-side surface S8 being convex. The fifth lens E5 has positive focal power, with its object-side surface S9 being concave and its image-side surface S10 being convex. The sixth lens E6 has negative focal power, with its object-side surface S11 being convex and its image-side surface S12 being concave. The seventh lens E7 has negative focal power, with its object-side surface S13 being convex and its image-side surface S14 being concave. The eighth lens element E8 has positive power, with its object-side surface S15 being convex and its image-side surface S16 being concave. The ninth lens element E9 has negative power, with its object-side surface S17 being convex and its image-side surface S18 being concave. The filter E10 has an object-side surface S19 and an image-side surface S20. Light from an object sequentially passes through surfaces S1 to S20 and is ultimately imaged on an imaging surface S21.

[0128] Table 1 shows the basic structural parameters of the optical imaging system of Example 1, wherein the units of curvature radius, thickness / distance, and focal length are all millimeters (mm).

[0129] Face number Surface type Radius of curvature thickness Refractive index Abbe number Cone coefficient OBJ spherical surface endless endless STO spherical surface endless -1.3134 S1 Aspheric 3.9263 1.4832 1.55 55.92 0.0416 S2 Aspheric 43.9776 0.1125 80.0428 S3 Aspheric 5.4439 0.4298 1.67 19.24 -5.7654 S4 Aspheric 3.5700 1.0548 -1.2279 S5 Aspheric 22.7096 0.2500 1.67 19.24 85.0229 S6 Aspheric 11.8179 0.1066 -3.6849 S7 Aspheric 20.8244 0.3767 1.56 47.84 -19.4922 S8 Aspheric -20.4893 0.0600 22.2317 S9 Aspheric -16.6349 1.1306 1.55 51.31 8.0651 S10 Aspheric -11.0136 0.1538 -7.9063 S11 Aspheric 12.3876 0.3291 1.59 28.53 -8.3169 S12 Aspheric 9.4084 0.4641 -3.2285 S13 Aspheric 58.0054 0.5644 1.59 ,32.46 98.9972 S14 Aspheric 33.4934 0.1701 -99.0000 S15 Aspheric 4.2686 1.0282 1.54 56 0.0052 S16 Aspheric 12.2416 1.0874 0.5254 S17 Aspheric 10.3866 0.5700 1.54, 55.71 0.7802 S18 Aspheric 2.6731 0.5252 -0.9705 S19 spherical surface endless 0.2100 1.52 64.17 S20 spherical surface endless 0.4334

[0130] Table 1

[0131] In Example 1, the object-side surface and the image-side surface of any lens from the first lens E1 to the ninth lens E9 are both aspherical surfaces. The surface shape of each aspherical lens can be defined by, but not limited to, the following aspherical surface formula:

[0132]

[0133] Where x is the distance vector from the vertex of the aspheric surface at a height of h along the optical axis; c is the paraxial curvature of the aspheric surface, c = 1 / R (i.e., paraxial curvature c is the reciprocal of the radius of curvature R in Table 1 above); k is the conic coefficient; and Ai is the correction coefficient for the i-th order of the aspheric surface. Table 2 below lists the high-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28, and A30 that can be used for each aspheric mirror surface S1-S18 in Example 1.

[0134]

[0135]

[0136] Table 2

[0137] Figure 2 The axial chromatic aberration curve of the optical imaging system of Example 1 is shown, which indicates the deviation of the focal point of light of different wavelengths after passing through the optical imaging system. Figure 3 An astigmatism curve of the optical imaging system of Example 1 is shown, which represents meridional field curvature and sagittal field curvature. Figure 4 The distortion curve of the optical imaging system of Example 1 is shown, which represents the distortion magnitude values ​​corresponding to different field angles. Figure 5 The chromatic aberration curve of the optical imaging system of Example 1 is shown, which represents the deviation of different image heights on the imaging surface after the light passes through the optical imaging system.

[0138] according to Figures 2 to 5 It can be seen that the optical imaging system given in Example 1 can achieve good imaging quality.

[0139] Example 2

[0140] like Figures 6 to 10 As shown, the optical imaging system of Example 2 of the present application is described. Figure 6 The schematic diagram of the structure of the optical imaging system of Example 2 is shown. For the sake of brevity, similar descriptions of some examples are omitted.

[0141] like Figure 6 As shown, the optical imaging system includes, from the object side to the image side, an aperture STO, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, an eighth lens E8, a ninth lens E9, a filter E10 and an imaging surface S21.

[0142] The first lens E1 has positive optical power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens E2 has negative optical power, with its object-side surface S3 being convex and its image-side surface S4 being concave. The third lens E3 has negative optical power, with its object-side surface S5 being convex and its image-side surface S6 being concave. The fourth lens E4 has positive optical power, with its object-side surface S7 being convex and its image-side surface S8 being convex. The fifth lens E5 has positive optical power, with its object-side surface S9 being concave and its image-side surface S10 being convex. The sixth lens E6 has negative optical power, with its object-side surface S11 being convex and its image-side surface S12 being concave. The seventh lens E7 has negative optical power, with its object-side surface S13 being concave and its image-side surface S14 being concave. The eighth lens element E8 has positive power, with its object-side surface S15 being convex and its image-side surface S16 being concave. The ninth lens element E9 has negative power, with its object-side surface S17 being convex and its image-side surface S18 being concave. The filter E10 has an object-side surface S19 and an image-side surface S20. Light from an object sequentially passes through surfaces S1 to S20 and is ultimately imaged on an imaging surface S21.

[0143] Table 3 shows the basic structural parameters of the optical imaging system of Example 2, wherein the units of curvature radius, thickness / distance, and focal length are all millimeters (mm).

[0144]

[0145]

[0146] Table 3

[0147] Table 4 shows the high-order coefficients of each aspheric mirror surface that can be used in Example 2, wherein each aspheric surface shape can be defined by formula (1) given in Example 1 above.

[0148] Face number A4 A6 A8 A10 A12 A14 A16 S1 2.9405E-02 -2.8156E-03 -4.9809E-03 -2.8946E-03 -1.5448E-03 -6.8594E-04 -3.8175E-04 S2 3.8165E-02 -9.6356E-03 -6.5193E-03 -5.8279E-04 -1.4871E-03 2.6156E-05 -2.6689E-04 S3 -4.7200E-02 3.6624E-02 -7.5976E-04 2.3725E-03 -6.9950E-04 2.5679E-04 -1.1256E-04 S4 -4.5381E-02 4.5628E-02 6.6235E-03 3.4051E-03 6.3648E-04 1.4814E-04 -2.2785E-05 S5 -4.7282E-01 3.4185E-02 -1.0807E-03 -2.8096E-03 -8.8221E-04 -5.0858E-04 -4.0858E-04 S6 -4.1583E-01 9.2311E-02 5.3502E-03 -1.6446E-03 2.5935E-04 -7.1951E-04 -4.5278E-04 S7 -2.9414E-01 7.0225E-03 1.0158E-02 5.0937E-03 1.2940E-03 -1.0847E-03 -1.2790E-04 S8 -7.1746E-02 1.6147E-02 1.5833E-02 -9.2648E-03 -2.6848E-03 -6.4996E-04 2.0594E-03 S9 1.8058E-02 -2.7877E-03 1.7099E-02 -1.0453E-02 2.0800E-03 1.4267E-03 1.4135E-03 S10 -8.8001E-01 6.4465E-02 4.7956E-03 7.6024E-03 4.1708E-03 1.8319E-03 7.3837E-04 S11 -1.3819E+00 5.5650E-01 -3.3348E-02 -9.9495E-03 -5.4759E-03 1.6020E-03 1.8805E-03 S12 -1.3514E+00 2.9749E-01 3.6773E-02 2.2317E-02 -1.1989E-03 6.0421E-04 -1.0830E-03 S13 -6.3307E-01 -1.3459E-01 7.1776E-02 3.5832E-02 -8.0750E-03 4.1636E-03 -4.3498E-04 S14 -9.6296E-01 2.4570E-01 1.9444E-02 2.1643E-02 -2.5131E-02 4.9306E-03 -3.6380E-04 S15 -3.6460E+00 1.6031E-01 9.4153E-02 -1.9482E-02 -5.5810E-03 -7.0372E-03 -3.9019E-03 S16 -1.3661E+00 -1.1818E-01 1.6818E-01 -8.9820E-02 3.7978E-02 -1.2502E-02 3.6956E-03 S17 -3.1947E+00 1.4007E+00 -5.9973E-01 2.2140E-01 -7.4752E-02 2.4977E-02 -1.2877E-02 S18 -8.1945E+00 1.9882E+00 -6.0038E-01 2.0154E-01 -9.4751E-02 4.5145E-02 -2.6813E-02 Face number A18 A20 A22 A24 A26 A28 A30 S1 -1.7298E-04 -1.1035E-04 -4.2488E-05 -2.7782E-05 -1.9965E-06 -3.4426E-06 8.3936E-06 S2 6.8358E-05 -6.5753E-05 2.9075E-06 -4.3007E-05 1.2817E-05 7.2923E-06 1.3016E-05 S3 1.2632E-04 2.4060E-07 4.9880E-05 -2.2327E-06 1.3454E-05 -3.3679E-06 -2.4388E-06 S4 -7.6962E-06 7.2316E-06 2.1593E-07 -9.9135E-06 -1.6586E-05 -4.6771E-06 -3.8780E-06 S5 -1.2179E-04 -2.1796E-05 -4.3308E-05 -3.0719E-05 -2.5018E-05 -6.4321E-06 -2.4546E-06 S6 1.1265E-04 2.4671E-04 1.1894E-05 -3.2754E-06 -3.9816E-05 5.9564E-07 -3.5567E-06 S7 5.9280E-05 3.2833E-04 6.8250E-05 2.0109E-05 -5.4407E-05 -1.8507E-05 -2.6989E-06 S8 -5.6513E-04 -1.2618E-04 6.8811E-05 9.7369E-05 -2.4832E-05 -1.8249E-05 4.4609E-06 S9 -1.3734E-03 -2.3152E-04 1.6510E-04 5.3630E-05 -6.0055E-05 -8.5335E-06 2.0923E-05 S10 2.0810E-04 -2.9207E-04 -9.4771E-05 -9.8820E-05 -4.5282E-05 -1.3121E-05 -3.3305E-06 S11 4.4467E-04 -1.0174E-03 1.1774E-04 -4.3355E-05 1.2231E-04 -2.4593E-05 -4.5864E-05 S12 5.6653E-04 -2.7845E-04 -2.1425E-05 -2.1507E-04 -3.9802E-05 -2.8299E-05 -1.4738E-05 S13 -1.4750E-03 -7.1549E-04 1.4256E-04 9.8897E-05 -1.9211E-05 -3.4420E-05 1.2067E-05 S14 -3.0060E-03 1.5112E-03 5.6741E-04 -1.8960E-04 -2.9912E-04 3.3105E-05 6.0640E-05 S15 -1.8516E-03 1.9858E-03 6.2219E-04 -3.1336E-04 -3.2819E-04 5.1878E-05 2.2048E-05 S16 -8.1768E-04 8.3490E-04 5.1900E-05 -4.0768E-04 1.5297E-04 -8.8059E-05 1.0719E-04 S17 7.9738E-03 -4.4442E-03 1.6375E-03 -5.9070E-04 4.0551E-04 -2.5915E-04 8.9758E-05 S18 1.3277E-02 -6.3305E-03 2.7321E-03 -1.3723E-03 8.7203E-04 -6.2898E-04 2.7326E-04

[0149] Table 4

[0150] Figure 7 The axial chromatic aberration curve of the optical imaging system of Example 2 is shown, which indicates the deviation of the focal point of light of different wavelengths after passing through the optical imaging system. Figure 8 The astigmatism curve of the optical imaging system of Example 2 is shown, which represents the meridional field curvature and the sagittal field curvature. Figure 9 The distortion curve of the optical imaging system of Example 2 is shown, which represents the distortion magnitude values ​​corresponding to different field angles. Figure 10 The magnification chromatic aberration curve of the optical imaging system of Example 2 is shown, which represents the deviation of different image heights on the imaging surface after the light passes through the optical imaging system.

[0151] according to Figures 7 to 10 It can be seen that the optical imaging system given in Example 2 can achieve good imaging quality.

[0152] Example 3

[0153] like Figures 11 to 15 As shown, the optical imaging system of Example 3 of the present application is described. Figure 11 The schematic diagram of the structure of the optical imaging system of Example 3 is shown. For the sake of brevity, similar descriptions of some examples are omitted.

[0154] like Figure 11 As shown, the optical imaging system includes, from the object side to the image side, an aperture STO, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, an eighth lens E8, a ninth lens E9, a filter E10 and an imaging surface S21.

[0155] The first lens E1 has positive focal power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens E2 has negative focal power, with its object-side surface S3 being convex and its image-side surface S4 being concave. The third lens E3 has negative focal power, with its object-side surface S5 being convex and its image-side surface S6 being concave. The fourth lens E4 has positive focal power, with its object-side surface S7 being convex and its image-side surface S8 being convex. The fifth lens E5 has positive focal power, with its object-side surface S9 being concave and its image-side surface S10 being convex. The sixth lens E6 has positive focal power, with its object-side surface S11 being convex and its image-side surface S12 being concave. The seventh lens E7 has negative focal power, with its object-side surface S13 being concave and its image-side surface S14 being concave. The eighth lens element E8 has positive power, with its object-side surface S15 being convex and its image-side surface S16 being concave. The ninth lens element E9 has negative power, with its object-side surface S17 being convex and its image-side surface S18 being concave. The filter E10 has an object-side surface S19 and an image-side surface S20. Light from an object sequentially passes through surfaces S1 to S20 and is ultimately imaged on an imaging surface S21.

[0156] Table 5 shows the basic structural parameters of the optical imaging system of Example 3, wherein the units of curvature radius, thickness / distance, and focal length are all millimeters (mm).

[0157]

[0158]

[0159] Table 5

[0160] Table 6 shows the high-order coefficients of each aspheric mirror surface that can be used in Example 3, wherein each aspheric surface shape can be defined by formula (1) given in Example 1 above.

[0161]

[0162]

[0163] Table 6

[0164] Figure 12 The axial chromatic aberration curve of the optical imaging system of Example 3 is shown, which indicates the deviation of the focal point of light of different wavelengths after passing through the optical imaging system. Figure 13 The astigmatism curve of the optical imaging system of Example 3 is shown, which represents the meridional field curvature and the sagittal field curvature. Figure 14 The distortion curve of the optical imaging system of Example 3 is shown, which represents the distortion magnitude values ​​corresponding to different field angles. Figure 15 The magnification chromatic aberration curve of the optical imaging system of Example 3 is shown, which represents the deviation of different image heights on the imaging surface after the light passes through the optical imaging system.

[0165] according to Figures 12 to 15 It can be seen that the optical imaging system given in Example 3 can achieve good imaging quality.

[0166] Example 4

[0167] like Figures 16 to 20 As shown, the optical imaging system of Example 4 of the present application is described. Figure 16 The schematic diagram of the structure of the optical imaging system of Example 4 is shown. For the sake of brevity, similar descriptions of some examples are omitted.

[0168] like Figure 16 As shown, the optical imaging system includes, from the object side to the image side, an aperture STO, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, an eighth lens E8, a ninth lens E9, a filter E10 and an imaging surface S21.

[0169] The first lens E1 has positive focal power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens E2 has negative focal power, with its object-side surface S3 being convex and its image-side surface S4 being concave. The third lens E3 has negative focal power, with its object-side surface S5 being convex and its image-side surface S6 being concave. The fourth lens E4 has positive focal power, with its object-side surface S7 being convex and its image-side surface S8 being convex. The fifth lens E5 has positive focal power, with its object-side surface S9 being concave and its image-side surface S10 being convex. The sixth lens E6 has negative focal power, with its object-side surface S11 being convex and its image-side surface S12 being concave. The seventh lens E7 has negative focal power, with its object-side surface S13 being concave and its image-side surface S14 being convex. The eighth lens element E8 has positive power, with its object-side surface S15 being convex and its image-side surface S16 being concave. The ninth lens element E9 has negative power, with its object-side surface S17 being convex and its image-side surface S18 being concave. The filter E10 has an object-side surface S19 and an image-side surface S20. Light from an object sequentially passes through surfaces S1 to S20 and is ultimately imaged on an imaging surface S21.

[0170] Table 7 shows the basic structural parameters of the optical imaging system of Example 4, where the units of curvature radius, thickness / distance, and focal length are all millimeters (mm).

[0171] Face number Surface type Radius of curvature thickness Refractive index Abbe number Cone coefficient OBJ spherical surface endless endless STO spherical surface endless -1.4197 S1 Aspheric 4.0651 1.6000 1.55 55.92 0.0468 S2 Aspheric 54.7269 0.0722 98.9451 S3 Aspheric 5.5782 0.5082 1.67 19.24 -5.5536 S4 Aspheric 3.6331 1.1317 -1.2806 S5 Aspheric 23.2047 0.1862 1.67 19.24 80.9754 S6 Aspheric 11.0015 0.1409 0.8131 S7 Aspheric 18.3337 0.4416 1.55 51.00 -9.6812 S8 Aspheric -19.6181 0.0647 27.7536 S9 Aspheric -16.0710 1.1327 1.56 45.68 6.2876 S10 Aspheric -12.6374 0.1993 -6.0351 S11 Aspheric 15.2245 0.4981 1.58 30.17 -4.2749 S12 Aspheric 12.4743 0.4748 -1.0636 S13 Aspheric -168.8429 0.4865 1.59 31.6 -98.8453 S14 Aspheric -533.8254 0.0806 75.4651 S15 Aspheric 4.5099 0.6640 1.54 56.00 0.0150 S16 Aspheric 9.7717 1.0009 -2.4434 S17 Aspheric 10.6788 0.9832 1.54 55.71 0.2458 S18 Aspheric 2.9110 0.6259 -0.9707 S19 spherical surface endless 0.2100 1.52 64.17 S20 spherical surface endless 0.5341

[0172] Table 7

[0173] Table 8 shows the high-order coefficients of each aspheric mirror surface that can be used in Example 4, where the surface shape of each aspheric surface can be defined by formula (1) given in Example 1 above.

[0174]

[0175]

[0176] Table 8

[0177] Figure 17 An axial chromatic aberration curve of the optical imaging system of Example 4 is shown, which indicates the deviation of the focal point of light of different wavelengths after passing through the optical imaging system. Figure 18 An astigmatism curve of the optical imaging system of Example 4 is shown, which represents meridional field curvature and sagittal field curvature. Figure 19 The distortion curve of the optical imaging system of Example 4 is shown, which represents the distortion magnitude values ​​corresponding to different field angles. Figure 20 The magnification chromatic aberration curve of the optical imaging system of Example 4 is shown, which represents the deviation of different image heights on the imaging surface after the light passes through the optical imaging system.

[0178] according to Figures 17 to 20 It can be seen that the optical imaging system given in Example 4 can achieve good imaging quality.

[0179] Example 5

[0180] like Figures 21 to 25 As shown, the optical imaging system of Example 5 of the present application is described. Figure 21 The schematic diagram of the structure of the optical imaging system of Example 5 is shown. For the sake of brevity, similar descriptions of some examples are omitted.

[0181] like Figure 21 As shown, the optical imaging system includes, from the object side to the image side, an aperture STO, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, an eighth lens E8, a ninth lens E9, a filter E10 and an imaging surface S21.

[0182] The first lens E1 has positive focal power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens E2 has negative focal power, with its object-side surface S3 being convex and its image-side surface S4 being concave. The third lens E3 has negative focal power, with its object-side surface S5 being convex and its image-side surface S6 being concave. The fourth lens E4 has positive focal power, with its object-side surface S7 being convex and its image-side surface S8 being convex. The fifth lens E5 has positive focal power, with its object-side surface S9 being concave and its image-side surface S10 being convex. The sixth lens E6 has negative focal power, with its object-side surface S11 being convex and its image-side surface S12 being concave. The seventh lens E7 has negative focal power, with its object-side surface S13 being convex and its image-side surface S14 being concave. The eighth lens element E8 has positive power, with its object-side surface S15 being convex and its image-side surface S16 being concave. The ninth lens element E9 has negative power, with its object-side surface S17 being convex and its image-side surface S18 being concave. The filter E10 has an object-side surface S19 and an image-side surface S20. Light from an object sequentially passes through surfaces S1 to S20 and is ultimately imaged on an imaging surface S21.

[0183] Table 9 shows the basic structural parameters of the optical imaging system of Example 5, where the units of curvature radius, thickness / distance, and focal length are all millimeters (mm).

[0184] Face number Surface type Radius of curvature thickness Refractive index Abbe number Cone coefficient OBJ spherical surface endless endless STO spherical surface endless -1.3194 S1 Aspheric 3.9915 1.4909 1.55 55.92 0.0457 S2 Aspheric 48.6267 0.1214 95.2207 S3 Aspheric 5.6789 0.4558 1.67 19.24 -5.5464 S4 Aspheric 3.6828 1.0872 -1.2165 S5 Aspheric 23.0228 0.2197 1.67 19.24 83.0035 S6 Aspheric 11.2691 0.1409 -0.8343 S7 Aspheric 20.0463 0.4308 1.54 55.94 -17.7698 S8 Aspheric -18.5600 0.0445 27.2992 S9 Aspheric -15.7495 1.1000 1.56 46.31 6.7504 S10 Aspheric -12.3095 0.1752 -8.4876 S11 Aspheric 14.8599 0.3781 1.59 34.61 -6.7687 S12 Aspheric 11.0098 0.4387 -2.4752 S13 Aspheric 155.2973 0.5430 1.57 34.43 99.0000 S14 Aspheric 96.1086 0.2083 -99.0000 S15 Aspheric 4.3014 1.1924 1.54 56.00 0.0053 S16 Aspheric 11.5629 1.0940 1.3128 S17 Aspheric 10.2701 0.4422 1.54 55.71 0.5771 S18 Aspheric 2.7416 0.5574 -0.9506 S19 spherical surface endless 0.2100 1.52 64.17 S20 spherical surface endless 0.4656

[0185] Table 9

[0186] Table 10 shows the high-order coefficients of each aspheric mirror surface that can be used in Example 5, where the surface shape of each aspheric surface can be defined by formula (1) given in Example 1 above.

[0187]

[0188]

[0189] Table 10

[0190] Figure 22 An axial chromatic aberration curve of the optical imaging system of Example 5 is shown, which indicates the deviation of the focal point of light of different wavelengths after passing through the optical imaging system. Figure 23 An astigmatism curve of the optical imaging system of Example 5 is shown, which represents meridional field curvature and sagittal field curvature. Figure 24 The distortion curve of the optical imaging system of Example 5 is shown, which represents the distortion magnitude values ​​corresponding to different field angles. Figure 25The magnification chromatic aberration curve of the optical imaging system of Example 5 is shown, which represents the deviation of different image heights on the imaging surface after the light passes through the optical imaging system.

[0191] according to Figures 22 to 25 It can be seen that the optical imaging system given in Example 5 can achieve good imaging quality.

[0192] Example 6

[0193] like Figures 26 to 30 As shown, the optical imaging system of Example 6 of the present application is described. Figure 26 The structure diagram of the optical imaging system of Example 6 is shown. For the sake of brevity, similar descriptions of some examples are omitted.

[0194] like Figure 26 As shown, the optical imaging system includes, from the object side to the image side, an aperture STO, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, an eighth lens E8, a ninth lens E9, a filter E10 and an imaging surface S21.

[0195] The first lens E1 has positive focal power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens E2 has negative focal power, with its object-side surface S3 being convex and its image-side surface S4 being concave. The third lens E3 has negative focal power, with its object-side surface S5 being convex and its image-side surface S6 being concave. The fourth lens E4 has positive focal power, with its object-side surface S7 being convex and its image-side surface S8 being convex. The fifth lens E5 has positive focal power, with its object-side surface S9 being concave and its image-side surface S10 being convex. The sixth lens E6 has negative focal power, with its object-side surface S11 being convex and its image-side surface S12 being concave. The seventh lens E7 has positive focal power, with its object-side surface S13 being convex and its image-side surface S14 being concave. The eighth lens element E8 has positive power, with its object-side surface S15 being convex and its image-side surface S16 being concave. The ninth lens element E9 has negative power, with its object-side surface S17 being convex and its image-side surface S18 being concave. The filter E10 has an object-side surface S19 and an image-side surface S20. Light from an object sequentially passes through surfaces S1 to S20 and is ultimately imaged on an imaging surface S21.

[0196] Table 11 shows the basic structural parameters of the optical imaging system of Example 6, where the units of curvature radius, thickness / distance, and focal length are all millimeters (mm).

[0197] Face number Surface type Radius of curvature thickness Refractive index Abbe number Cone coefficient OBJ spherical surface endless endless STO spherical surface endless -1.3730 S1 Aspheric 4.0160 1.5868 1.55 55.92 0.0505 S2 Aspheric 49.9951 0.0864 92.0938 S3 Aspheric 6.0130 0.4613 1.67 19.24 -6.3512 S4 Aspheric 3.8339 1.0369 -1.3641 S5 Aspheric 22.9612 0.1831 1.67 19.24 82.5555 S6 Aspheric 10.3877 0.1073 -2.5497 S7 Aspheric 17.2016 0.3665 1.58 37.95 -8.2761 S8 Aspheric -25.0720 0.1958 24.9023 S9 Aspheric -17.4007 1.2409 1.55 51.46 15.0030 S10 Aspheric -13.0136 0.1528 -8.2065 S11 Aspheric 11.6252 0.3495 1.6 31.65 -9.3732 S12 Aspheric 9.0737 0.4026 -4.0498 S13 Aspheric 36.8243 0.7610 1.58 34.83 25.1235 S14 Aspheric 53.1853 0.1667 -99.0000 S15 Aspheric 4.2785 0.9628 1.54 56.00 0.0032 S16 Aspheric 10.6962 1.3137 0.2543 S17 Aspheric 10.8218 0.3324 1.54 55.71 0.6246 S18 Aspheric 2.8005 0.5456 -0.9430 S19 spherical surface endless 0.2100 1.52 64.17 S20 spherical surface endless 0.4538

[0198] Table 11

[0199] Table 12 shows the high-order coefficients of each aspheric mirror surface that can be used in Example 6, where each aspheric surface shape can be defined by formula (1) given in Example 1 above.

[0200] Face number A4 A6 A8 A10 A12 A14 A16 S1 3.2573E-02 -2.3416E-03 -4.9224E-03 -2.7133E-03 -1.4753E-03 -6.0906E-04 -3.4917E-04 S2 3.7862E-02 -9.9089E-03 -5.0504E-03 -1.3694E-03 -1.0361E-03 -1.3643E-04 -1.7706E-04 S3 -5.2662E-02 4.1351E-02 1.4436E-03 9.9538E-04 -3.4199E-04 9.3261E-05 -6.3809E-05 S4 -5.1258E-02 4.8938E-02 8.7962E-03 3.1875E-03 7.2059E-04 1.1849E-04 -4.4386E-05 S5 -4.6471E-01 3.7961E-02 -2.5365E-03 -3.3902E-03 -9.7727E-04 -7.3083E-04 -5.7775E-04 S6 -4.1291E-01 8.5536E-02 4.3913E-03 2.3092E-05 1.0705E-03 -9.8700E-04 -6.4612E-04 S7 -2.8916E-01 1.1484E-02 1.3639E-02 3.9543E-03 1.0940E-03 -1.3046E-03 -7.2235E-05 S8 -6.4192E-02 1.6734E-02 1.6259E-02 -8.6963E-03 -2.7325E-03 -2.4281E-04 1.3541E-03 S9 -1.8509E-02 -3.8458E-03 2.1478E-02 -5.7539E-03 5.6840E-04 7.1083E-04 7.2371E-04 S10 -8.8145E-01 7.1991E-02 1.5617E-02 4.0349E-03 4.7362E-03 4.7870E-04 6.4708E-04 S11 -1.3820E+00 5.2156E-01 -2.8865E-02 -1.1775E-02 -9.5703E-04 -1.7832E-03 1.8515E-03 S12 -1.3783E+00 2.9237E-01 3.7384E-02 2.1123E-02 -6.1213E-04 -2.9348E-04 -1.3333E-03 S13 -7.0639E-01 -1.1730E-01 8.9701E-02 3.4827E-02 -6.7487E-03 4.2372E-03 -2.0774E-03 S14 -9.8625E-01 2.4422E-01 2.8579E-02 1.8175E-02 -2.2373E-02 3.9911E-03 -8.3936E-04 S15 -3.7928E+00 1.9197E-01 8.7089E-02 -3.1560E-02 -8.3943E-03 -7.5605E-03 -4.0036E-03 S16 -1.3527E+00 -1.1972E-01 1.6262E-01 -8.3515E-02 4.4945E-02 -1.5707E-02 4.4421E-03 S17 -3.3306E+00 1.4720E+00 -6.2312E-01 2.3666E-01 -8.5153E-02 2.8156E-02 -1.4572E-02 S18 -8.1213E+00 2.0306E+00 -6.2700E-01 2.0855E-01 -9.6608E-02 4.6598E-02 -2.7751E-02 Face number A18 A20 A22 A24 A26 A28 A30 S1 -1.4442E-04 -1.0406E-04 -3.2680E-05 -2.4405E-05 4.7842E-09 -5.9052E-06 8.0118E-06 S2 3.9811E-05 -4.8539E-05 2.3682E-06 -2.8602E-05 1.3292E-05 1.3848E-06 1.0916E-05 S3 1.1235E-04 1.2644E-05 4.6263E-05 -6.2356E-06 9.4099E-06 -2.1645E-06 -5.2105E-07 S4 -1.3112E-05 2.6035E-06 3.4640E-06 -4.8464E-06 -1.0278E-05 -4.3815E-06 -3.9741E-06 S5 -1.8425E-04 7.4157E-06 -6.0253E-05 -3.0669E-05 -4.7927E-05 -1.1840E-05 -5.6280E-06 S6 1.0826E-04 3.6626E-04 4.5825E-05 3.3932E-06 -6.9873E-05 -1.0103E-05 1.9586E-06 S7 1.5050E-04 3.5801E-04 9.6671E-05 4.7949E-07 -6.7895E-05 -4.1576E-05 1.1185E-05 S8 -1.6885E-04 -1.6858E-04 -1.0593E-06 5.6520E-05 8.0746E-06 -2.4362E-05 6.2998E-06 S9 -6.2291E-04 -3.3556E-04 8.6530E-06 6.7021E-05 1.6243E-05 -1.3438E-05 8.4548E-06 S10 -5.3659E-05 -3.5056E-04 -7.9982E-05 -1.0423E-04 -1.2474E-05 -4.9640E-06 3.5394E-06 S11 3.1456E-04 -9.2297E-04 3.7661E-04 -3.1656E-04 1.7280E-04 -2.0806E-05 -1.5593E-05 S12 9.7645E-04 -6.7567E-04 3.5163E-04 -3.6489E-04 1.6575E-05 -5.3277E-05 -8.6332E-06 S13 -2.7903E-04 -9.2021E-04 5.5250E-05 -1.0624E-04 2.4327E-05 3.9023E-05 2.7800E-05 S14 -1.9483E-03 1.1209E-03 2.2466E-04 3.4808E-05 -1.4267E-04 2.2854E-05 -6.4863E-06 S15 -3.0702E-03 2.3755E-03 3.8092E-04 -2.9994E-04 -2.6559E-04 2.9630E-05 -5.0868E-05 S16 -2.7601E-03 2.6375E-03 -5.8938E-04 -1.1216E-04 -1.3918E-04 -8.5687E-05 1.2443E-04 S17 8.9607E-03 -3.8657E-03 4.5021E-04 -4.3725E-04 8.7650E-04 -6.0668E-04 1.6904E-04 S18 1.2764E-02 -5.9288E-03 2.7334E-03 -1.3910E-03 8.7356E-04 -7.5325E-04 3.3573E-04

[0201] Table 12

[0202] Figure 27 An axial chromatic aberration curve of the optical imaging system of Example 6 is shown, which indicates the deviation of the focal point of light of different wavelengths after passing through the optical imaging system. Figure 28 An astigmatism curve of the optical imaging system of Example 6 is shown, which represents meridional field curvature and sagittal field curvature. Figure 29 The distortion curve of the optical imaging system of Example 6 is shown, which represents the distortion magnitude values ​​corresponding to different field angles. Figure 30 The magnification chromatic aberration curve of the optical imaging system of Example 6 is shown, which represents the deviation of different image heights on the imaging surface after the light passes through the optical imaging system.

[0203] according to Figures 27 to 30 It can be seen that the optical imaging system given in Example 6 can achieve good imaging quality.

[0204] In summary, Examples 1 to 6 respectively satisfy the relationships shown in Table 13.

[0205] Conditional / Example 1 2 3 4 5 6 TTL / f 1.32 1.29 1.30 1.28 1.31 1.30 ∑CT / ∑AT 1.92 1.92 1.92 2.05 1.89 1.80 (V1+V2+V3) / 3 31.47 31.47 31.47 31.47 31.47 31.47 R2 / R1 11.20 12.07 11.53 13.46 12.18 12.45 R4 / R3 0.66 0.64 0.62 0.65 0.65 0.64 R6 / R5 0.52 0.49 0.46 0.47 0.49 0.45 R17 / f 1.30 1.21 1.27 1.24 1.24 1.29 R17 / R18 3.89 3.71 3.79 3.67 3.75 3.86 R9 / R10 1.51 1.24 1.17 1.27 1.28 1.34 R9 / f5 -0.30 -0.16 -0.11 -0.17 -0.17 -0.20 R11 / R12 1.32 1.08 0.97 1.22 1.35 1.28 R11 / f 1.55 1.88 1.75 1.77 1.80 1.39 CT5 / CT4 3.00 2.54 2.11 2.57 2.55 3.39 (f4-f) / |R8+R7| 31.53 5.32 16.33 6.70 6.35 1.18 V1 / V4 1.17 2.84 1.06 1.10 1.00 1.47 V7 / V5 0.63 0.69 0.66 0.69 0.74 0.68 T23 / (CT2-CT3) 5.87 4.71 17.66 3.51 4.60 3.73 (CT6+CT8+CT7) / (T67+T78) 3.03 3.03 3.39 2.97 3.27 3.64 f3 / (f1+f2) 4.05 3.68 3.32 3.37 3.59 3.07 BFL / CT9 2.05 1.96 2.47 1.39 2.79 3.64 (ET9+ET8) / (CT9+CT8) 1.42 1.54 1.63 1.52 1.53 1.75 f8 / f9 -1.67 -1.71 -1.72 -1.88 -1.66 -1.73 (R16+R15) / (R16-R15) 2.07 2.28 2.39 2.71 2.18 2.33 T67 / T56 3.02 2.67 2.45 2.38 2.50 2.64 (V4+V5+V6) / 3 42.56 32.46 44.20 42.28 45.62 40.35 f1 / CT1 5.25 5.05 4.96 4.97 5.28 4.98

[0206] Table 13

[0207] Table 14 shows the effective focal lengths f1 to f9 of the lenses of the optical imaging systems of Examples 1 to 6.

[0208]

[0209]

[0210] Table 14

[0211] The present application also provides an imaging device, wherein the electronic photosensitive element thereof can be a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS). The imaging device can be a standalone imaging device such as a digital camera, or an imaging module integrated into a mobile electronic device such as a mobile phone. The imaging device is equipped with the optical imaging system described above.

[0212] Obviously, the embodiments described above are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0213] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, tasks, devices, components and / or combinations thereof.

[0214] It should be noted that the terms "first," "second," and the like in the specification and claims of this application and the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein.

[0215] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. An optical imaging system, characterized in that: The optical imaging system is a nine-element imaging system, which includes, from the object side to the image side along the optical axis: a first lens having positive refractive power, wherein the object-side surface of the first lens is convex and the image-side surface of the first lens is concave; a second lens having negative optical power, wherein the object-side surface of the second lens is convex and the image-side surface of the second lens is concave; a third lens having negative optical power, wherein the object-side surface of the third lens is convex and the image-side surface of the third lens is concave; a fourth lens having positive refractive power, wherein the object-side surface of the fourth lens is convex, and the image-side surface of the fourth lens is convex; a fifth lens having positive optical power, wherein the object-side surface of the fifth lens is concave and the image-side surface of the fifth lens is convex; a sixth lens having optical power, wherein the object-side surface of the sixth lens is convex and the image-side surface of the sixth lens is concave; a seventh lens having optical power; an eighth lens having positive optical power, wherein the object-side surface of the eighth lens is convex and the image-side surface of the eighth lens is concave; a ninth lens element having negative optical power, wherein the object-side surface of the ninth lens element is convex and the image-side surface of the ninth lens element is concave; The entrance pupil diameter EPD of the optical imaging system and the effective focal length f of the optical imaging system satisfy the following conditions: 8.01 / 5.80≤f / EPD≤8.39 / 5.99; The curvature radius R17 of the object side surface of the ninth lens and the effective focal length f of the optical imaging system satisfy the following relationship: 1.21≤R17 / f≤1.30; The Abbe number V1 of the first lens, the Abbe number V2 of the second lens, and the Abbe number V3 of the third lens satisfy the following: 30<(V1+V2+V3) / 3<32; A center thickness CT4 of the fourth lens on the optical axis and a center thickness CT5 of the fifth lens on the optical axis satisfy the following: 2.11≤CT5 / CT4≤3.

39.

2. The optical imaging system according to claim 1, wherein: A curvature radius R17 of the object-side surface of the ninth lens and a curvature radius R18 of the image-side surface of the ninth lens satisfy the following relationship: 3.67≤R17 / R18≤3.

89.

3. The optical imaging system according to claim 1, wherein: The curvature radius R9 of the object-side surface of the fifth lens and the curvature radius R10 of the image-side surface of the fifth lens satisfy the following relationship: 1.17≤R9 / R10≤1.51; the curvature radius R9 of the object-side surface of the fifth lens and the effective focal length f5 of the fifth lens satisfy the following relationship: -0.3≤R9 / f5≤-0.

11.

4. The optical imaging system according to claim 1, wherein: The curvature radius R11 of the object side surface of the sixth lens and the curvature radius R12 of the image side surface of the sixth lens satisfy the following relationship: 0.97≤R11 / R12≤1.35; the curvature radius R11 of the object side surface of the sixth lens and the effective focal length f of the optical imaging system satisfy the following relationship: 1.39≤R11 / f≤1.

88.

5. The optical imaging system according to claim 1, wherein: The center thickness CT1 of the first lens on the optical axis and the center thickness CTi of any lens from the second lens to the ninth lens on the optical axis satisfy the following: CT1 / CTi>1, where i is a value selected from 2, 3, 4, 5, 6, 7, 8, and 9.

6. The optical imaging system according to claim 1, wherein: The effective focal length f4 of the fourth lens, the curvature radius R7 of the object side surface of the fourth lens, the curvature radius R8 of the image side surface of the fourth lens and the effective focal length f of the optical imaging system satisfy the following relationship: 1.18≤(f4-f) / |R8+R7|≤31.

53.

7. The optical imaging system according to claim 1, wherein: The Abbe number V1 of the first lens and the Abbe number V4 of the fourth lens satisfy the following relationship: 1≤V1 / V4≤2.84, and the Abbe number V5 of the fifth lens and the Abbe number V7 of the seventh lens satisfy the following relationship: 0.63≤V7 / V5≤0.

74.

8. The optical imaging system according to claim 1, wherein: A center thickness CT2 of the second lens on the optical axis, a center thickness CT3 of the third lens on the optical axis, and an air interval T23 between the second lens and the third lens on the optical axis satisfy the following: 3.51≤T23 / (CT2-CT3)≤17.

66.

9. The optical imaging system according to claim 1, wherein: A center thickness CT6 of the sixth lens on the optical axis, a center thickness CT7 of the seventh lens on the optical axis, a center thickness CT8 of the eighth lens on the optical axis, an air gap T67 between the sixth lens and the seventh lens on the optical axis, and an air gap T78 between the seventh lens and the eighth lens on the optical axis satisfy the following: 2.97≤(CT6+CT8+CT7) / (T67+T78)≤3.

64.

10. The optical imaging system according to any one of claims 1 to 9, characterized in that: The effective focal length f1 of the first lens, the effective focal length f2 of the second lens, and the effective focal length f3 of the third lens satisfy the following: 3.07≤f3 / (f1+f2)≤4.

05.

11. The optical imaging system according to any one of claims 1 to 9, characterized in that: A center thickness CT9 of the ninth lens on the optical axis and a distance BFL from the image side surface of the last lens of the optical imaging system to the imaging plane of the optical imaging system on the optical axis satisfy the following relationship: 1.39≤BFL / CT9≤3.

64.

12. The optical imaging system according to any one of claims 1 to 9, characterized in that: The curvature radius of any side surface of any lens from the first lens to the third lens satisfies: Rn>0, where n is a value selected from 1, 2, 3, 4, 5, and 6. The curvature radius R1 of the object-side surface of the first lens and the curvature radius R2 of the image-side surface of the first lens satisfy: R2 / R1>10. The curvature radius R3 of the object-side surface of the second lens, the curvature radius R4 of the image-side surface of the second lens, the curvature radius R5 of the object-side surface of the third lens, and the curvature radius R6 of the image-side surface of the third lens satisfy: R6 / R5. <R4 / R3<1。 13. The optical imaging system according to any one of claims 1 to 9, characterized in that: The sum of the thicknesses ΣCT of the first to ninth lenses on the optical axis and the sum of the air intervals ΣAT between any two adjacent lenses from the first to ninth lenses on the optical axis satisfy the following: 1.8≤ΣCT / ΣAT≤2.

05.

14. The optical imaging system according to any one of claims 1 to 9, characterized in that: The distance TTL from the object side of the first lens to the imaging plane of the optical imaging system on the optical axis and the effective focal length f of the optical imaging system satisfy the following: 1.28≤TTL / f≤1.32, half of the diagonal length of the effective pixel area on the imaging plane of the optical imaging system ImgH satisfies the following: 6.35mm≤ImgH≤6.38mm, and the maximum field of view FOV of the optical imaging system satisfies the following: 71.99°≤FOV≤76.96°.

15. The optical imaging system according to any one of claims 1 to 9, characterized in that: An edge thickness ET8 of the eighth lens, an edge thickness ET9 of the ninth lens, a center thickness CT8 of the eighth lens on the optical axis, and a center thickness CT9 of the ninth lens on the optical axis satisfy the following: 1.42≤(ET9+ET8) / (CT9+CT8)≤1.

75.

16. The optical imaging system according to any one of claims 1 to 9, wherein: The effective focal length f8 of the eighth lens and the effective focal length f9 of the ninth lens satisfy: -1.88≤f8 / f9≤-1.66, and the curvature radius R15 of the object side surface of the eighth lens and the curvature radius R16 of the image side surface of the eighth lens satisfy: 2.07≤(R16+R15) / (R16-R15)≤2.

71.

17. The optical imaging system according to any one of claims 1 to 9, characterized in that: An air interval T56 between the fifth lens and the sixth lens on the optical axis and an air interval T67 between the sixth lens and the seventh lens on the optical axis satisfy the following: 2.38≤T67 / T56≤3.

02.

18. The optical imaging system according to any one of claims 1 to 9, characterized in that: The Abbe number V4 of the fourth lens, the Abbe number V5 of the fifth lens, and the Abbe number V6 of the sixth lens satisfy the following relationship: 32.46≤(V4+V5+V6) / 3≤45.

62.

19. The optical imaging system according to any one of claims 1 to 9, characterized in that: The effective focal length f1 of the first lens and the center thickness CT1 of the first lens satisfy the following: 4.96≤f1 / CT1≤5.

28.

20. An optical imaging system, characterized in that: The optical imaging system is a nine-element imaging system, which includes, from the object side to the image side along the optical axis: a first lens having positive refractive power, wherein the object-side surface of the first lens is convex and the image-side surface of the first lens is concave; a second lens having negative optical power, wherein the object-side surface of the second lens is convex and the image-side surface of the second lens is concave; a third lens having negative optical power, wherein the object-side surface of the third lens is convex and the image-side surface of the third lens is concave; a fourth lens having positive refractive power, wherein the object-side surface of the fourth lens is convex, and the image-side surface of the fourth lens is convex; a fifth lens having positive optical power, wherein the object-side surface of the fifth lens is concave and the image-side surface of the fifth lens is convex; a sixth lens having optical power, wherein the object-side surface of the sixth lens is convex and the image-side surface of the sixth lens is concave; a seventh lens having optical power; an eighth lens having positive optical power, wherein the object-side surface of the eighth lens is convex and the image-side surface of the eighth lens is concave; a ninth lens element having negative optical power, wherein the object-side surface of the ninth lens element is convex and the image-side surface of the ninth lens element is concave; The entrance pupil diameter EPD of the optical imaging system and the effective focal length f of the optical imaging system satisfy the following conditions: 8.01 / 5.80≤f / EPD≤8.39 / 5.99; A curvature radius R17 of the object-side surface of the ninth lens and a curvature radius R18 of the image-side surface of the ninth lens satisfy the following relationship: 3.67≤R17 / R18≤3.89; The Abbe number V1 of the first lens, the Abbe number V2 of the second lens, and the Abbe number V3 of the third lens satisfy the following relationship: 30<(V1+V2+V3) / 3<32.

21. The optical imaging system according to claim 20, wherein: The curvature radius R9 of the object-side surface of the fifth lens and the curvature radius R10 of the image-side surface of the fifth lens satisfy the following relationship: 1.17≤R9 / R10≤1.51; the curvature radius R9 of the object-side surface of the fifth lens and the effective focal length f5 of the fifth lens satisfy the following relationship: -0.3≤R9 / f5≤-0.

11.

22. The optical imaging system according to claim 20, wherein: The curvature radius R11 of the object side surface of the sixth lens and the curvature radius R12 of the image side surface of the sixth lens satisfy the following relationship: 0.97≤R11 / R12≤1.35; the curvature radius R11 of the object side surface of the sixth lens and the effective focal length f of the optical imaging system satisfy the following relationship: 1.39≤R11 / f≤1.

88.

23. The optical imaging system according to claim 20, wherein: A center thickness CT4 of the fourth lens on the optical axis and a center thickness CT5 of the fifth lens on the optical axis satisfy the following: 2.11≤CT5 / CT4≤3.

39.

24. The optical imaging system according to claim 20, wherein: The center thickness CT1 of the first lens on the optical axis and the center thickness CTi of any lens from the second lens to the ninth lens on the optical axis satisfy the following: CT1 / CTi>1, where i is a value selected from 2, 3, 4, 5, 6, 7, 8, and 9.

25. The optical imaging system according to claim 20, wherein: The effective focal length f4 of the fourth lens, the curvature radius R7 of the object side surface of the fourth lens, the curvature radius R8 of the image side surface of the fourth lens and the effective focal length f of the optical imaging system satisfy the following relationship: 1.18≤(f4-f) / |R8+R7|≤31.

53.

26. The optical imaging system according to claim 20, wherein: The Abbe number V1 of the first lens and the Abbe number V4 of the fourth lens satisfy the following relationship: 1≤V1 / V4≤2.84, and the Abbe number V5 of the fifth lens and the Abbe number V7 of the seventh lens satisfy the following relationship: 0.63≤V7 / V5≤0.

74.

27. The optical imaging system according to claim 20, wherein: A center thickness CT2 of the second lens on the optical axis, a center thickness CT3 of the third lens on the optical axis, and an air interval T23 between the second lens and the third lens on the optical axis satisfy the following: 3.51≤T23 / (CT2-CT3)≤17.

66.

28. The optical imaging system according to claim 20, wherein: A center thickness CT6 of the sixth lens on the optical axis, a center thickness CT7 of the seventh lens on the optical axis, a center thickness CT8 of the eighth lens on the optical axis, an air gap T67 between the sixth lens and the seventh lens on the optical axis, and an air gap T78 between the seventh lens and the eighth lens on the optical axis satisfy the following: 2.97≤(CT6+CT8+CT7) / (T67+T78)≤3.

64.

29. The optical imaging system according to any one of claims 20 to 28, wherein: The effective focal length f1 of the first lens, the effective focal length f2 of the second lens, and the effective focal length f3 of the third lens satisfy the following: 3.07≤f3 / (f1+f2)≤4.

05.

30. The optical imaging system according to any one of claims 20 to 28, wherein: A center thickness CT9 of the ninth lens on the optical axis and a distance BFL from the image side surface of the last lens of the optical imaging system to the imaging plane of the optical imaging system on the optical axis satisfy the following relationship: 1.39≤BFL / CT9≤3.

64.

31. The optical imaging system according to any one of claims 20 to 28, wherein: The curvature radius of any side surface of any lens from the first lens to the third lens satisfies: Rn>0, where n is a value selected from 1, 2, 3, 4, 5, and 6. The curvature radius R1 of the object-side surface of the first lens and the curvature radius R2 of the image-side surface of the first lens satisfy: R2 / R1>10. The curvature radius R3 of the object-side surface of the second lens, the curvature radius R4 of the image-side surface of the second lens, the curvature radius R5 of the object-side surface of the third lens, and the curvature radius R6 of the image-side surface of the third lens satisfy: R6 / R5. <R4 / R3<1。 32. The optical imaging system according to any one of claims 20 to 28, wherein: The sum of the thicknesses ΣCT of the first to ninth lenses on the optical axis and the sum of the air intervals ΣAT between any two adjacent lenses from the first to ninth lenses on the optical axis satisfy the following: 1.8≤ΣCT / ΣAT≤2.

05.

33. The optical imaging system according to any one of claims 20 to 28, wherein: The distance TTL from the object side of the first lens to the imaging plane of the optical imaging system on the optical axis and the effective focal length f of the optical imaging system satisfy the following: 1.28≤TTL / f≤1.32, half of the diagonal length of the effective pixel area on the imaging plane of the optical imaging system ImgH satisfies the following: 6.35mm≤ImgH≤6.38mm, and the maximum field of view FOV of the optical imaging system satisfies the following: 71.99°≤FOV≤76.96°.

34. The optical imaging system according to any one of claims 20 to 28, wherein: An edge thickness ET8 of the eighth lens, an edge thickness ET9 of the ninth lens, a center thickness CT8 of the eighth lens on the optical axis, and a center thickness CT9 of the ninth lens on the optical axis satisfy the following: 1.42≤(ET9+ET8) / (CT9+CT8)≤1.

75.

35. The optical imaging system according to any one of claims 20 to 28, wherein: The effective focal length f8 of the eighth lens and the effective focal length f9 of the ninth lens satisfy: -1.88≤f8 / f9≤-1.66, and the curvature radius R15 of the object side surface of the eighth lens and the curvature radius R16 of the image side surface of the eighth lens satisfy: 2.07≤(R16+R15) / (R16-R15)≤2.

71.

36. The optical imaging system according to any one of claims 20 to 28, wherein: An air interval T56 between the fifth lens and the sixth lens on the optical axis and an air interval T67 between the sixth lens and the seventh lens on the optical axis satisfy the following: 2.38≤T67 / T56≤3.

02.

37. The optical imaging system according to any one of claims 20 to 28, wherein: The Abbe number V4 of the fourth lens, the Abbe number V5 of the fifth lens, and the Abbe number V6 of the sixth lens satisfy the following relationship: 32.46≤(V4+V5+V6) / 3≤45.

62.

38. The optical imaging system according to any one of claims 20 to 28, wherein: The effective focal length f1 of the first lens and the center thickness CT1 of the first lens satisfy the following: 4.96≤f1 / CT1≤5.28.

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