Optical imaging device

Abstract

The present invention provides an optical imaging device. The number of lenses with optical power in the optical imaging device is eight. The optical imaging device includes a lens group, a spacer element group, and a lens barrel. Among them, the distance L from the object-side end face of the lens barrel to the image-side end face of the lens barrel in the direction of the optical axis of the optical imaging device and the sum ∑CP of the thicknesses of all spacer elements in the spacer element group satisfy: 3.42 ≤ L / ∑CP ≤ 4.64; the radius of curvature R8 of the image-side surface of the fourth lens, the radius of curvature R9 of the object-side surface of the fifth lens, and the interval EP45 between the fourth spacer element and the fifth spacer element in the direction of the optical axis satisfy: -2.73 ≤ (R8 + R9) / EP45 ≤ -1.52. This application solves the problem of serious stray light in the front and rear lens groups of the optical imaging device under a large aperture in the prior art.

Description

Technical Field

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

[0002] With the development of smartphone photography technology, users' demand for the night shooting ability of smartphones is increasing day by day. Under such technical requirements, one of the design trends of the main camera optical imaging device of mobile phones is to increase the aperture of the optical imaging device to capture more light, thereby improving the shooting effect in low-light environments. Although increasing the aperture can capture more light in low-light environments, the stray light suppression effect of the optical imaging device with a large aperture is not good. This is because after more light enters the optical imaging device, especially when there is a large difference in the apertures of the front lens group and the rear lens group of the optical imaging device, the light connection in the transition area between the front and rear lens groups is poor, resulting in serious stray light and greatly reducing the imaging quality. Therefore, how to control the shape size and light trend of the transition area between the front and rear lens groups of the optical imaging device with a large aperture, and reduce stray light while ensuring stable assembly, is a very important issue. Summary of the Invention

[0003] The main object of the present invention is to provide an optical imaging device to solve the problem of serious stray light between the front and rear lens groups of the optical imaging device in the prior art under a large aperture.

[0004] To achieve the above object, in one aspect of the present invention, there is provided an optical imaging device. The number of lenses with optical power in the optical imaging device is eight. The optical imaging device includes: a lens group. From the object side to the image side of the optical imaging device, the lens group includes the first lens to the eighth lens arranged at intervals in sequence. The first lens has a positive optical power. The object side surface of the first lens is convex, and the image side surface of the first lens is concave. The second lens has a positive optical power. The object side surface of the second lens is convex, and the image side surface of the second lens is concave. The third lens has a negative optical power. The object side surface of the third lens is convex, and the image side surface of the third lens is concave. The fourth lens has a positive optical power. The object side surface of the fourth lens is convex, and the image side surface of the fourth lens is convex. The fifth lens has a negative optical power. The object side surface of the fifth lens is convex, and the image side surface of the fifth lens is concave. The sixth lens has a positive optical power. The object side surface of the sixth lens is convex, and the image side surface of the sixth lens is convex. The seventh lens has a negative optical power. The object side surface of the seventh lens is concave. The eighth lens has a negative optical power. The object side surface of the eighth lens is concave; a spacer element group. The spacer element group at least includes a first spacer element located between the first lens and the second lens and at least partially in contact with the image side surface of the first lens, a second spacer element located between the second lens and the third lens and at least partially in contact with the image side surface of the second lens, a third spacer element located between the third lens and the fourth lens and at least partially in contact with the image side surface of the third lens, a fourth spacer element located between the fourth lens and the fifth lens and at least partially in contact with the image side surface of the fourth lens, a fifth spacer element located between the fifth lens and the sixth lens and at least partially in contact with the image side surface of the fifth lens, a sixth spacer element located between the sixth lens and the seventh lens and at least partially in contact with the image side surface of the sixth lens, a seventh spacer element located between the seventh lens and the eighth lens and at least partially in contact with the image side surface of the seventh lens, and an eighth spacer element located on the image side of the eighth lens and at least partially in contact with the image side surface of the eighth lens; a lens barrel. The lens group and the spacer element group are accommodated in the lens barrel; wherein, the distance L from the object side end face of the lens barrel to the image side end face of the lens barrel in the direction of the optical axis of the optical imaging device and the sum ∑CP of the thicknesses of all spacer elements in the spacer element group satisfy: 3.42 ≤ L / ∑CP ≤ 4.64; the radius of curvature R8 of the image side surface of the fourth lens, the radius of curvature R9 of the object side surface of the fifth lens, and the interval EP45 between the fourth spacer element and the fifth spacer element in the direction of the optical axis satisfy: -2.73 ≤ (R8 + R9) / EP45 ≤ -1.52; the combined focal length f45 of the fourth lens and the fifth lens, the inner diameter d5s of the object side surface of the fifth spacer element, and the inner diameter d3s of the object side surface of the third spacer element satisfy: 5.40 ≤ f45 / (d5s - d3s) ≤ 7.62.

[0005] According to another aspect of the present invention, an optical imaging device is provided. The optical imaging device has eight lenses with optical powers. The optical imaging device includes: a lens group. From the object side to the image side of the optical imaging device, the lens group includes a first lens to an eighth lens arranged at intervals in sequence. The first lens has a positive optical power. The object side surface of the first lens is convex, and the image side surface of the first lens is concave. The second lens has a positive optical power. The object side surface of the second lens is convex, and the image side surface of the second lens is concave. The third lens has a negative optical power. The object side surface of the third lens is convex, and the image side surface of the third lens is concave. The fourth lens has a positive optical power. The object side surface of the fourth lens is convex, and the image side surface of the fourth lens is convex. The fifth lens has a negative optical power. The object side surface of the fifth lens is convex, and the image side surface of the fifth lens is concave. The sixth lens has a positive optical power. The object side surface of the sixth lens is convex, and the image side surface of the sixth lens is convex. The seventh lens has a negative optical power. The object side surface of the seventh lens is concave. The eighth lens has a negative optical power. The object side surface of the eighth lens is concave; a spacer element group. The spacer element group at least includes a first spacer element located between the first lens and the second lens and at least partially contacting the image side surface of the first lens, a second spacer element located between the second lens and the third lens and at least partially contacting the image side surface of the second lens, a third spacer element located between the third lens and the fourth lens and at least partially contacting the image side surface of the third lens, a fourth spacer element located between the fourth lens and the fifth lens and at least partially contacting the image side surface of the fourth lens, a fifth spacer element located between the fifth lens and the sixth lens and at least partially contacting the image side surface of the fifth lens, a sixth spacer element located between the sixth lens and the seventh lens and at least partially contacting the image side surface of the sixth lens, a seventh spacer element located between the seventh lens and the eighth lens and at least partially contacting the image side surface of the seventh lens, an eighth spacer element located on the image side of the eighth lens and at least partially contacting the image side surface of the eighth lens; a lens barrel. The lens group and the spacer element group are accommodated in the lens barrel; wherein, the radius of curvature R15 of the object side surface of the eighth lens, the interval EP78 between the seventh spacer element and the eighth spacer element in the optical axis direction, and the refractive index N8 of the eighth lens satisfy: 10.42 ≤ |R15| / EP78 × N8 ≤ 14.17; the interval EP78 between the seventh spacer element and the eighth spacer element in the optical axis direction, the maximum thickness CP8 of the eighth spacer element in the optical axis direction, and the central thickness CT8 of the eighth lens on the optical axis satisfy: 3.70 ≤ (EP78 + CP8) / CT8 ≤ 5.18.

[0006] Furthermore, the entrance pupil diameter EPD of the optical imaging device, the outer diameter D1s of the object side surface of the first spacer element, and the inner diameter d1s of the object side surface of the first spacer element satisfy: 1.91 ≤ EPD / (D1s - d1s) ≤ 2.34.

[0007] Furthermore, the effective focal length f7 of the seventh lens, the effective focal length f8 of the eighth lens, and the inner diameter d7s of the object side of the seventh spacer element satisfy: 3.23 ≤ |f7 + f8| / d7s ≤ 10.40.

[0008] Furthermore, the inner diameter d4m of the image side of the fourth spacer element, the inner diameter d4s of the object side of the fourth spacer element, and the central thickness CT4 of the fourth lens on the optical axis satisfy: -0.10 ≤ (d4m - d4s) / CT4 ≤ 1.70.

[0009] Furthermore, the outer diameter D6s of the object side of the sixth spacer element, the interval EP56 between the fifth spacer element and the sixth spacer element in the direction of the optical axis, and the central thickness CT6 of the sixth lens on the optical axis satisfy: 3.37 ≤ D6s / (EP56 + CT6) ≤ 5.47.

[0010] Furthermore, the curvature radius R7 of the object side of the fourth lens and the curvature radius R8 of the image side of the fourth lens satisfy: -4.50 ≤ R7 / R8 ≤ -3.52, and the outer diameter D3m of the image side of the third spacer element and the outer diameter D4s of the object side of the fourth spacer element satisfy: 9.68 ≤ D3m / D4s × 10 ≤ 11.12.

[0011] Furthermore, the outer diameter D5m of the image side of the fifth spacer element, the inner diameter d5m of the image side of the fifth spacer element, and the curvature radius R11 of the object side of the sixth lens satisfy: 0.07 ≤ (D5m + d5m) / R11 ≤ 0.65.

[0012] Furthermore, the curvature radius R15 of the object side of the eighth lens, the interval EP78 between the seventh spacer element and the eighth spacer element in the direction of the optical axis, and the refractive index N8 of the eighth lens satisfy: 10.42 ≤ |R15| / EP78 × N8 ≤ 14.17.

[0013] Furthermore, the interval EP45 between the fourth spacer element and the fifth spacer element in the direction of the optical axis and the interval EP56 between the fifth spacer element and the sixth spacer element in the direction of the optical axis satisfy: 0.55 ≤ EP45 / EP56 ≤ 1.18.

[0014] Furthermore, the outer diameter D4s of the object side of the fourth spacer element, the inner diameter d4s of the object side of the fourth spacer element, and the curvature radius R8 of the image side of the fourth lens satisfy: 0.08 ≤ (D4s - d4s) / |R8| ≤ 0.52.

[0015] Further, the distance L from the object-side end face of the lens barrel to the image-side end face of the lens barrel in the direction of the optical axis of the optical imaging device, the sum ∑AT of the air spaces on the optical axis between any two adjacent lenses among the first lens to the eighth lens, the central thickness CT7 of the seventh lens on the optical axis, and the central thickness CT8 of the eighth lens on the optical axis satisfy: 4.38 ≤ (L - ∑AT) / (CT7 + CT8) ≤ 6.15.

[0016] Further, the outer diameter D4s of the object-side surface of the fourth spacer element, the spacing EP34 between the third spacer element and the fourth spacer element in the direction of the optical axis, and the central thickness CT4 of the fourth lens on the optical axis satisfy: 3.60 ≤ D4s / (EP34 + CT4) ≤ 5.14.

[0017] Further, the spacing EP67 between the sixth spacer element and the seventh spacer element in the direction of the optical axis and the effective focal length f7 of the seventh lens satisfy: -1.11 ≤ EP67 / f7 × 10 ≤ -0.22, and the spacing EP78 between the seventh spacer element and the eighth spacer element in the direction of the optical axis and the effective focal length f8 of the eighth lens satisfy: -1.91 ≤ EP78 / f8 × 10 ≤ -0.83.

[0018] Further, the on-axis distance TD from the object-side surface of the first lens to the image-side surface of the eighth lens, the on-axis distance TTL from the object-side surface of the first lens to the imaging surface of the optical imaging device, and the inner diameter d0s of the object-side end face of the lens barrel satisfy: 4.79 ≤ TD / TTL × d0s ≤ 5.83.

[0019] Applying the technical solution of the present invention, an optical imaging device is provided. The number of lenses with optical power in the optical imaging device is eight. The optical imaging device includes a lens group, a spacer element group, and a lens barrel. From the object side to the image side of the optical imaging device, the lens group includes a first lens to an eighth lens arranged at intervals in sequence. The first lens has a positive optical power. The object side surface of the first lens is convex, and the image side surface of the first lens is concave. The second lens has a positive optical power. The object side surface of the second lens is convex, and the image side surface of the second lens is concave. The third lens has a negative optical power. The object side surface of the third lens is convex, and the image side surface of the third lens is concave. The fourth lens has a positive optical power. The object side surface of the fourth lens is convex, and the image side surface of the fourth lens is convex. The fifth lens has a negative optical power. The object side surface of the fifth lens is convex, and the image side surface of the fifth lens is concave. The sixth lens has a positive optical power. The object side surface of the sixth lens is convex, and the image side surface of the sixth lens is convex. The seventh lens has a negative optical power. The object side surface of the seventh lens is concave. The eighth lens has a negative optical power. The object side surface of the eighth lens is concave; the spacer element group at least includes a first spacer element located between the first lens and the second lens and at least partially contacting the image side surface of the first lens, a second spacer element located between the second lens and the third lens and at least partially contacting the image side surface of the second lens, a third spacer element located between the third lens and the fourth lens and at least partially contacting the image side surface of the third lens, a fourth spacer element located between the fourth lens and the fifth lens and at least partially contacting the image side surface of the fourth lens, a fifth spacer element located between the fifth lens and the sixth lens and at least partially contacting the image side surface of the fifth lens, a sixth spacer element located between the sixth lens and the seventh lens and at least partially contacting the image side surface of the sixth lens, a seventh spacer element located between the seventh lens and the eighth lens and at least partially contacting the image side surface of the seventh lens, and an eighth spacer element located on the image side of the eighth lens and at least partially contacting the image side surface of the eighth lens; the lens group and the spacer element group are accommodated in the lens barrel; wherein, the distance L from the object side end face of the lens barrel to the image side end face of the lens barrel in the direction of the optical axis of the optical imaging device and the sum ∑CP of the thicknesses of all spacer elements in the spacer element group satisfy: 3.42 ≤ L / ∑CP ≤ 4.64; the radius of curvature R8 of the image side surface of the fourth lens, the radius of curvature R9 of the object side surface of the fifth lens, and the interval EP45 between the fourth spacer element and the fifth spacer element in the direction of the optical axis satisfy: -2.73 ≤ (R8 + R9) / EP45 ≤ -1.52; the combined focal length f45 of the fourth lens and the fifth lens, the inner diameter d5s of the object side surface of the fifth spacer element, and the inner diameter d3s of the object side surface of the third spacer element satisfy: 5.40 ≤ f45 / (d5s - d3s) ≤ 7.62.

[0020] The optical imaging device of the present application uses eight lenses with optical power, and the first lens to the eighth lens are arranged in sequence at intervals. In the optical imaging device of the present application, by controlling L / ∑CP and (R8 + R9) / EP45 within a reasonable range, the overall shape of the transition region where there is an aperture difference between the front and rear lens groups, that is, between the fourth lens and the fifth lens, can be controlled. However, in this transition region, large-aperture light beams are likely to be incident on the lens structure part, resulting in stray light problems. By controlling f45 / (d5s - d3s) within a reasonable range, the light deflection path can be controlled, reducing the risk of marginal light rays incident on the lens structure part. At the same time, the inner diameters of the third and fifth spacer elements are used to effectively intercept stray light, thereby effectively suppressing the stray light intensity in imaging under a large aperture caused by the aperture difference between the front and rear lens groups, and improving the overall imaging level of the optical imaging device. Brief Description of the Drawings

[0021] The specification drawings forming a part of the present application are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0022] Figure 1 A partial parameter schematic diagram of an optical imaging device according to any optional embodiment of the present invention is shown;

[0023] Figure 2 A schematic structural diagram of the optical imaging device according to Embodiment 1 of the present invention is shown;

[0024] Figure 3 A schematic structural diagram of the optical imaging device according to Embodiment 2 of the present invention is shown;

[0025] Figure 4 A schematic structural diagram of the optical imaging device according to Embodiment 3 of the present invention is shown;

[0026] Figures 5 to 7 The longitudinal chromatic aberration curve, astigmatism curve, and distortion curve of the optical imaging device according to Embodiment 1 are respectively shown;

[0027] Figure 8 A schematic structural diagram of the optical imaging device according to Embodiment 4 of the present invention is shown;

[0028] Figure 9 A schematic structural diagram of the optical imaging device according to Embodiment 5 of the present invention is shown;

[0029] Figure 10 A schematic structural diagram of the optical imaging device according to Embodiment 6 of the present invention is shown;

[0030] Figures 11 to 13 The longitudinal chromatic aberration curve, astigmatism curve, and distortion curve of the optical imaging device according to Embodiment 4 are respectively shown;

[0031] Figure 14 Shows a schematic structural diagram of the optical imaging device according to the seventh embodiment of the present invention;

[0032] Figure 15 Shows a schematic structural diagram of the optical imaging device according to the eighth embodiment of the present invention;

[0033] Figure 16 Shows a schematic structural diagram of the optical imaging device according to the ninth embodiment of the present invention;

[0034] Figures 17 to 19 Respectively show the longitudinal chromatic aberration curve, astigmatism curve, and distortion curve of the optical imaging device according to the seventh embodiment;

[0035] Figures 20 to 21 Respectively show the stray light optical path diagram and stray light spot diagram of the optical imaging device under the conditions of L / ∑CP = 3.50, (R8 + R9) / EP45 = -1.50, and f45 / (d5s - d3s) = 6.55 in an alternative embodiment of the present invention;

[0036] Figures 22 to 23 Respectively show the stray light optical path diagram and stray light spot diagram of the optical imaging device under the conditions of L / ∑CP = 3.50, (R8 + R9) / EP45 = -1.50, and f45 / (d5s - d3s) = 7.24 in an alternative embodiment of the present invention;

[0037] Figures 24 to 25 Respectively show the stray light optical path diagram and stray light spot diagram of the optical imaging device under the conditions of L / ∑CP = 3.50, (R8 + R9) / EP45 = -1.50, and f45 / (d5s - d3s) = 8.64 in the prior art;

[0038] Figures 26 to 27 Respectively show the stray light optical path diagram and stray light spot diagram of the optical imaging device under the conditions of L / ∑CP = 3.50, (R8 + R9) / EP45 = -1.50, and f45 / (d5s - d3s) = 5.04 in the prior art.

[0039] Among them, the above-mentioned drawings include the following reference numerals:

[0040] P0, lens barrel; E1, first lens; P1, first spacer element; E2, second lens; P2, second spacer element; E3, third lens; P3, third spacer element; E4, fourth lens; P4, fourth spacer element; E5, fifth lens; P5, fifth spacer element; E6, sixth lens; P6, sixth spacer element; E7, seventh lens; P7, seventh spacer element; E8, eighth lens; P8, eighth spacer element; S1, object side of the first lens; S2, image side of the first lens; S3, object side of the second lens; S4, image side of the second lens; S5, object side of the third lens; S6, image side of the third lens; S7, object side of the fourth lens; S8, image side of the fourth lens; S9, object side of the fifth lens; S10, image side of the fifth lens; S11, object side of the sixth lens; S12, image side of the sixth lens; S13, object side of the seventh lens; S14, image side of the seventh lens; S15, object side of the eighth lens; S16, image side of the eighth lens. Detailed implementation manners

[0041] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments may be combined with each other. The present invention will be described in detail below with reference to the drawings and in combination with the embodiments.

[0042] It should be pointed out that unless otherwise specified, all technical and scientific terms used in the present application have the same meanings as those commonly understood by those of ordinary skill in the technical field to which the present application belongs.

[0043] In the present invention, unless otherwise stated, the orientation terms such as "upper, lower, top, bottom" are generally in the directions shown in the drawings, or in the vertical, perpendicular or gravitational directions of the components themselves; similarly, for the convenience of understanding and description, "inner, outer" refer to the inner and outer of the contours of the components themselves, but the above orientation terms are not used to limit the present invention.

[0044] It should be noted that in this specification, the expressions of the first, second, third, etc. are only used to distinguish one feature from another feature, and do not represent any limitation on the features. Therefore, without departing from the teachings of the present application, the first lens discussed below may also be referred to as the second lens or the third lens.

[0045] In the drawings, for the convenience of illustration, the thickness, size and shape of the lenses have been slightly exaggerated. Specifically, the spherical or aspherical shapes shown in the drawings are shown by way of example. That is, the spherical or aspherical shapes are not limited to the spherical or aspherical shapes shown in the drawings. The drawings are only examples and are not drawn strictly to scale.

[0046] In this text, the paraxial region refers to the region 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 region; 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 region. The judgment of the surface shape in the paraxial region can be based on the judgment method of those with ordinary knowledge in the field, and the positive or negative of the R value (R refers to the radius of curvature in the paraxial region, usually the R value on the lens database in optical software) is used to judge whether it is convex or concave. For the eye side surface, 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 display side surface, 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.

[0047] To solve the problem of serious stray light in the front and rear lens groups of an optical imaging device in the prior art under a large aperture, the present invention provides an optical imaging device.

[0048] First Embodiment

[0049] As Figures 1 to 23As shown, the number of lenses with optical power in the optical imaging device is eight. The optical imaging device includes a lens group, a spacer element group, and a barrel. From the object side to the image side of the optical imaging device, the lens group includes the first lens to the eighth lens arranged at intervals in sequence. The first lens has a positive optical power. The object side surface of the first lens is convex, and the image side surface of the first lens is concave. The second lens has a positive optical power. The object side surface of the second lens is convex, and the image side surface of the second lens is concave. The third lens has a negative optical power. The object side surface of the third lens is convex, and the image side surface of the third lens is concave. The fourth lens has a positive optical power. The object side surface of the fourth lens is convex, and the image side surface of the fourth lens is convex. The fifth lens has a negative optical power. The object side surface of the fifth lens is convex, and the image side surface of the fifth lens is concave. The sixth lens has a positive optical power. The object side surface of the sixth lens is convex, and the image side surface of the sixth lens is convex. The seventh lens has a negative optical power. The object side surface of the seventh lens is concave. The eighth lens has a negative optical power. The object side surface of the eighth lens is concave. The spacer element group at least includes a first spacer element located between the first lens and the second lens and at least partially in contact with the image side surface of the first lens, a second spacer element located between the second lens and the third lens and at least partially in contact with the image side surface of the second lens, a third spacer element located between the third lens and the fourth lens and at least partially in contact with the image side surface of the third lens, a fourth spacer element located between the fourth lens and the fifth lens and at least partially in contact with the image side surface of the fourth lens, a fifth spacer element located between the fifth lens and the sixth lens and at least partially in contact with the image side surface of the fifth lens, a sixth spacer element located between the sixth lens and the seventh lens and at least partially in contact with the image side surface of the sixth lens, a seventh spacer element located between the seventh lens and the eighth lens and at least partially in contact with the image side surface of the seventh lens, and an eighth spacer element located on the image side of the eighth lens and at least partially in contact with the image side surface of the eighth lens. The lens group and the spacer element group are accommodated in the barrel. Among them, the distance L from the object side end face of the barrel to the image side end face of the barrel in the direction of the optical axis of the optical imaging device and the sum ∑CP of the thicknesses of all spacer elements in the spacer element group satisfy: 3.42 ≤ L / ∑CP ≤ 4.64; the radius of curvature R8 of the image side surface of the fourth lens, the radius of curvature R9 of the object side surface of the fifth lens, and the interval EP45 between the fourth spacer element and the fifth spacer element in the direction of the optical axis satisfy: -2.73 ≤ (R8 + R9) / EP45 ≤ -1.52; the combined focal length f45 of the fourth lens and the fifth lens, the inner diameter d5s of the object side surface of the fifth spacer element, and the inner diameter d3s of the object side surface of the third spacer element satisfy: 5.40 ≤ f45 / (d5s - d3s) ≤ 7.62.

[0050] The optical imaging device of the present application uses eight lenses with optical power, and the first lens to the eighth lens are arranged in sequence at intervals. In the optical imaging device of the present application, by controlling L / ∑CP and (R8+R9) / EP45 within a reasonable range, the overall shape of the transition region where there is a difference in aperture between the front and rear lens groups, that is, between the fourth lens and the fifth lens, can be controlled. However, in this transition region, large-aperture light beams are likely to be incident on the lens structure part, resulting in stray light problems. By controlling f45 / (d5s-d3s) within a reasonable range, the light deflection path can be controlled, the risk of marginal light rays being incident on the lens structure part can be reduced, and at the same time, the inner diameters of the third and fifth spacer elements are used to effectively intercept stray light, thereby effectively suppressing the intensity of stray light in imaging under a large aperture caused by the difference in aperture between the front and rear lens groups, and improving the overall imaging level of the optical imaging device.

[0051] Table 1 below shows the stray light distribution of the optical imaging devices of Alternative Embodiment 2, Alternative Embodiment 3 of the present application and prior art Alternative Embodiment 1 and Alternative Embodiment 4 when L / ∑CP = 3.50, (R8+R9) / EP45 = -1.50, and f45 / (d5s-d3s) takes different values. Among them, the stray light spot diagram is used to show the imaging deviation of light rays in the optical imaging device. The abscissa is the X coordinate axis perpendicular to the optical axis of the imaging plane, and the ordinate is the Y coordinate axis perpendicular to the optical axis and the X coordinate axis of the imaging plane, with the unit of mm. The X coordinate axis and the Y coordinate axis show the stray light spot effect under the conditions that the off-axis angle of the light rays is 15°, the half milliradian (MH / 2) is 4.91 (unit: 0.5 mrad), and the standard luminous flux (FLux) of the chief ray is 1 (unit: lm).

[0052] Table 1

[0053]

[0054] The optical imaging devices shown in Alternative Embodiment 1 and Alternative Embodiment 4 belong to the prior art. Under the prerequisite conditions of L / ∑CP = 3.50 and (R8+R9) / EP45 = -1.50, the value of f45 / (d5s-d3s) in Alternative Embodiment 1 is 8.64. That is, when the value of f45 / (d5s-d3s) is too large, as Figure 24 and Figure 25 shown, the deviation of the off-axis light rays between the fourth lens and the fifth lens is large, and the ghosting on the imaging plane is serious; under the prerequisite conditions of L / ∑CP = 3.50 and (R8+R9) / EP45 = -1.50, the value of f45 / (d5s-d3s) in Alternative Embodiment 4 is 5.04. That is, when the value of f45 / (d5s-d3s) is too small, as Figure 26 and Figure 27As shown, the off-axis light is significantly deviated in the path between the fourth lens and the fifth lens, and there are many ghost spots in the imaging area. The imaging of Solution 1 and Solution 4 is affected by stray light spots and shows low contrast, resulting in poor imaging quality.

[0055] The optical imaging devices shown in Solution 2 and Solution 3 belong to the embodiments of the present application. Under the prerequisite conditions of L / ∑CP = 3.50 and (R8 + R9) / EP45 = -1.50, the value of f45 / (d5s - d3s) in Solution 2 and Solution 3 is within 5.40 - 7.62. As Figures 20 to 23 shown, the light travels well between the fourth lens and the fifth lens, and the light deviation of the corresponding stray light optical path diagram is extremely small. The stray light of Solution 2 and Solution 3 is effectively suppressed, significantly improving the imaging quality of the optical imaging device. That is to say, by restricting f45 / (d5s - d3s) within a reasonable range, the combined focal length of the fourth lens and the fifth lens, and the difference between the inner diameter of the object side of the fifth spacer element and the inner diameter of the object side of the third spacer element are controlled within a certain proportional range, which can effectively suppress the stray light intensity of imaging under a large aperture caused by the difference in the aperture of the front and rear lens groups, and improve the overall imaging level of the optical imaging device.

[0056] In this embodiment, the entrance pupil diameter EPD, the outer diameter D1s of the object side of the first spacer element, and the inner diameter d1s of the object side of the first spacer element of the optical imaging device satisfy: 1.91 ≤ EPD / (D1s - d1s) ≤ 2.34. If the value of EPD / (D1s - d1s) is too large, the assembly complexity will increase due to the expansion of the front-end size of the optical imaging device. If the value of EPD / (D1s - d1s) is too small, it will lead to insufficient light collection of the optical imaging device, an increase in aberration on the imaging surface, affecting the imaging quality and the performance of the optical imaging device in a dark environment. By restricting EPD / (D1s - d1s) within a reasonable range, by controlling the ratio of the entrance pupil diameter of the optical imaging device and the difference between the outer diameter and the inner diameter of the object side of the first spacer element, the outer diameter of the front lens can be effectively controlled to be appropriate, and the front-end size of the optical imaging device is further reduced.

[0057] In this embodiment, the effective focal length f7 of the seventh lens, the effective focal length f8 of the eighth lens, and the inner diameter d7s of the object side of the seventh spacer element satisfy: 3.23 ≤ |f7 + f8| / d7s ≤ 10.40. If the value of |f7 + f8| / d7s is too large, the total focal length of the seventh lens and the eighth lens becomes extremely large relative to the inner diameter of the object side of the seventh spacer element, increasing the degree of stray light and exacerbating the aberration of the optical imaging device. If the value of |f7 + f8| / d7s is too small, it will lead to a decrease in the clarity and sharpness of the imaging, especially the poor performance of details in the edge region, while increasing the complexity of the optical imaging device and additional correction requirements. By restricting |f7 + f8| / d7s within a reasonable range, the ratio of the effective focal lengths of the seventh lens and the eighth lens to the inner diameter of the object side of the seventh spacer element can be effectively controlled, thereby controlling the range of marginal rays of the seventh lens and the eighth lens, avoiding the generation of stray light while ensuring the optical parameters, and improving the image quality of the imaging surface.

[0058] In this embodiment, the inner diameter d4m of the image side of the fourth spacer element, the inner diameter d4s of the object side of the fourth spacer element, and the central thickness CT4 of the fourth lens on the optical axis satisfy: -0.10 ≤ (d4m - d4s) / CT4 ≤ 1.70. If the value of (d4m - d4s) / CT4 is too large, the light rays of the optical imaging device are unevenly distributed in the radial direction, the stray light is exacerbated, and further the clarity and contrast of the imaging are reduced. If the value of (d4m - d4s) / CT4 is too small, it will lead to difficulties in controlling the edge thickness of the fourth lens, while restricting the light path, exacerbating the aberration, and reducing the imaging quality. By restricting (d4m - d4s) / CT4 within a reasonable range, the proportional relationship between the difference in the inner diameter of the image side of the fourth spacer element and the inner diameter of the object side of the fourth spacer element and the central thickness of the fourth lens on the optical axis can be controlled, thereby controlling the overall shape within the effective diameter region of the fourth lens, and improving the processing and forming stability of the optical imaging device.

[0059] In this embodiment, the outer diameter D6s of the object side surface of the sixth spacer element, the interval EP56 between the fifth spacer element and the sixth spacer element in the optical axis direction, and the central thickness CT6 of the sixth lens on the optical axis satisfy: 3.37 ≤ D6s / (EP56 + CT6) ≤ 5.47. If the value of D6s / (EP56 + CT6) is too large, the rear end size of the optical imaging device increases significantly, and the outer diameter of the sixth spacer element expands. This not only affects the compactness and portability of the optical imaging device but also causes uneven thickness distribution of the rear flange structure of the optical imaging device, increasing the assembly difficulty. If the value of D6s / (EP56 + CT6) is too small, it will lead to a reduction in the effective utilization of light at the edge of the sixth lens, increasing the lens forming risk and reducing the imaging clarity and contrast under large aperture and complex light conditions. By restricting D6s / (EP56 + CT6) within a reasonable range and controlling the ratio of the outer diameter of the object side surface of the sixth spacer element, the interval between the fifth spacer element and the sixth spacer element in the optical axis direction, and the sum of the central thickness of the sixth lens on the optical axis, the rear end size of the optical imaging device is controlled, and thus the overall uniformity of the sixth lens is controlled. In addition, D6s indirectly controls the outer diameter size of the image side surface of the sixth lens, and EP56 and CT6 indirectly control the central thickness and the edge thickness of the sixth lens, meeting the overall uniformity requirements of the sixth lens, avoiding the risk of poor forming of the sixth lens, and reducing the stray light degree in the effective diameter edge necking area caused by insufficient forming filling.

[0060] In this embodiment, the following conditions are satisfied between the radius of curvature R7 of the object side surface of the fourth lens and the radius of curvature R8 of the image side surface of the fourth lens: -4.50 ≤ R7 / R8 ≤ -3.52, and the following conditions are satisfied between the outer diameter D3m of the image side surface of the third spacer element and the outer diameter D4s of the object side surface of the fourth spacer element: 9.68 ≤ D3m / D4s × 10 ≤ 11.12. If the value of R7 / R8 is too large, the object side surface of the fourth lens is flatter than the image side surface of the fourth lens, the control of light in the edge region is weakened, resulting in an increase in stray light and aberration. If the value of R7 / R8 is too small, the biconvex shape of the fourth lens will overly compress the light, and the deflection and scattering of light at the edge will intensify, also affecting the imaging quality. By restricting R7 / R8 within a reasonable range, the ratio of the radius of curvature of the object side surface of the fourth lens to the radius of curvature of the image side surface of the fourth lens is controlled, that is, the edge thickness of the effective diameter of the fourth lens is indirectly controlled, avoiding the situation where the radius of curvature of the image side surface of the fourth lens is too small to squeeze the edge thickness of the effective diameter, and reducing the degree of stray light caused by insufficient filling during the forming process due to excessive necking down. At the same time, if the value of D3m / D4s × 10 is too large, the stray light and reflection in the optical imaging device increase, reducing the imaging clarity and at the same time increasing the size of the optical imaging device. If the value of D3m / D4s × 10 is too small, the gap between the edge of the effective diameter of the fourth lens and the image side surface of the third spacer element becomes too narrow, restricting the freedom of light passing, reducing the propagation efficiency of light between the lenses, the imaging brightness and the imaging details. By restricting D3m / D4s × 10 within a reasonable range, the ratio of the outer diameter of the image side surface of the third spacer element to the outer diameter of the object side surface of the fourth spacer element can be controlled, indirectly controlling the outer diameter size of the fourth lens, controlling the size of the transition region between the front and rear lens groups of the optical imaging device, and effectively suppressing the stray light generated by the fourth lens.

[0061] In this embodiment, the outer diameter D5m of the image side surface of the fifth spacer element, the inner diameter d5m of the image side surface of the fifth spacer element, and the curvature radius R11 of the object side surface of the sixth lens satisfy: 0.07 ≤ (D5m + d5m) / R11 ≤ 0.65. If the value of (D5m + d5m) / R11 is too large, the effective diameter of the edge of the sixth lens is severely constricted, and light undergoes strong refraction or scattering in the edge region, reducing the light passing ability in this region and resulting in a significant increase in the risk of stray light. If the value of (D5m + d5m) / R11 is too small, the thickness of the edge region of the sixth lens is relatively large, and due to the insufficient curvature radius of the edge of the sixth lens, it is more difficult to form the sixth lens. By restricting (D5m + d5m) / R11 within a reasonable range, by controlling the ratio of the sum of the outer diameter of the image side surface of the fifth spacer element and the inner diameter of the image side surface of the fifth spacer element to the curvature radius of the object side surface of the sixth lens, the inner diameter size of the fifth spacer element can be controlled while indirectly restricting the outer diameter size of the sixth lens, avoiding the risk of stray light caused by an overly large inner diameter size of the fifth spacer element. At the same time, by controlling the curvature radius of the object side surface of the sixth lens, and thus controlling the convexity degree of the object side surface of the sixth lens, a double-convex structure with the image side surface of the sixth lens is avoided, which affects the thickness of the edge of the effective diameter and reduces the forming risk of the sixth lens.

[0062] In this embodiment, the curvature radius R15 of the object side surface of the eighth lens, the interval EP78 between the seventh spacer element and the eighth spacer element in the optical axis direction, and the refractive index N8 of the eighth lens satisfy: 10.42 ≤ |R15| / EP78 × N8 ≤ 14.17. If the value of |R15| / EP78 × N8 is too large, the shape of the object side surface of the eighth lens will be too flat, resulting in problems such as insufficient light convergence, increased aberration in the edge region, and decreased brightness and contrast. If the value of |R15| / EP78 × N8 is too small, the light management at the edge of the eighth lens is difficult due to excessive outward convexity of the eighth lens, increasing stray light and aberration, and also restricting the flexibility of the back focal design and spatial layout of the optical imaging device. By restricting |R15| / EP78 × N8 within a reasonable range, the product of the curvature radius of the object side surface of the eighth lens, the interval between the seventh spacer element and the eighth spacer element in the optical axis direction, and the refractive index of the eighth lens can be controlled, thereby controlling the convexity degree of the eighth lens, avoiding the lens protruding out to the rear end of the lens barrel, and at the same time controlling the light range of the outer field of view of the eighth lens, avoiding the generation of excessive stray light in the optical imaging device.

[0063] In this embodiment, the interval EP45 between the fourth spacer element and the fifth spacer element in the optical axis direction and the interval EP56 between the fifth spacer element and the sixth spacer element in the optical axis direction satisfy: 0.55 ≤ EP45 / EP56 ≤ 1.18. If the value of EP45 / EP56 is too large, the thickness of the fifth spacer element, i.e., between the fifth and sixth lenses, is reduced, resulting in a decrease in its structural stability and strength, and further reducing the assembly accuracy and durability of the optical imaging device. If the value of EP45 / EP56 is too small, the thickness distribution of the structural regions of the fifth and sixth lenses is unbalanced, increasing the molding risk of the sixth lens. By restricting EP45 / EP56 within a reasonable range, the ratio of the interval between the fourth spacer element and the fifth spacer element in the optical axis direction and the interval between the fifth spacer element and the sixth spacer element in the optical axis direction can be controlled, the thickness distribution of the structural regions of the fifth and sixth lenses can be controlled, and at the same time, good molding of the fifth and sixth lenses can be ensured.

[0064] In this embodiment, the outer diameter D4s of the object side surface of the fourth spacer element, the inner diameter d4s of the object side surface of the fourth spacer element, and the radius of curvature R8 of the image side surface of the fourth lens satisfy: 0.08 ≤ (D4s - d4s) / |R8| ≤ 0.52. If the value of (D4s - d4s) / |R8| is too large, the ratio of the effective diameter region of the fourth spacer element to the lens radius of curvature increases significantly, resulting in an imbalance in the matching between the thickness of the edge region of the fourth lens and the radius of curvature. If the value of (D4s - d4s) / |R8| is too small, the matching between the thickness of the edge region of the fourth lens and the radius of curvature is too tight, unable to ensure effective refraction and diffusion of light. By restricting (D4s - d4s) / |R8| within a reasonable range, the ratio of the difference between the outer diameter of the object side surface of the fourth spacer element and the inner diameter of the object side surface of the fourth spacer element and the radius of curvature of the image side surface of the fourth lens can be controlled, and thus the inner diameter of the fourth spacer element can be controlled, while avoiding stray light and controlling the convexity of the fourth lens.

[0065] In this embodiment, the distance L from the object-side end face of the lens barrel to the image-side end face of the lens barrel in the direction of the optical axis of the optical imaging device, the sum ∑AT of the air gaps between any two adjacent lenses among the first lens to the eighth lens on the optical axis, the central thickness CT7 of the seventh lens on the optical axis, and the central thickness CT8 of the eighth lens on the optical axis satisfy: 4.38 ≤ (L - ∑AT) / (CT7 + CT8) ≤ 6.15. If (L - ∑AT) / (CT7 + CT8) is too large, the total length of the optical imaging device increases significantly relative to the sum of the central thicknesses of the lenses, resulting in an overly loose internal space in the lens barrel, poor stability between the lenses and the lens barrel, and an increased risk of stability such as assembly step differences. If (L - ∑AT) / (CT7 + CT8) is too small, the internal space in the lens barrel is too compact, resulting in insufficient air gaps between the lenses, affecting the propagation and focusing efficiency of light between the lenses, exacerbating aberrations at large apertures, and reducing the clarity and uniformity of imaging. By restricting (L - ∑AT) / (CT7 + CT8) within a reasonable range, the difference between the distance from the object-side end face of the lens barrel to the image-side end face of the lens barrel in the direction of the optical axis of the optical imaging device and the sum of the air gaps between any two adjacent lenses among the first lens to the eighth lens on the optical axis is controlled, thereby controlling the positions of the seventh lens and the eighth lens in the optical imaging device, which is beneficial to the layout of the structural area between the rear lens group of the optical imaging device and the lens barrel, and reduces the risk of stability such as assembly step differences.

[0066] In this embodiment, the outer diameter D4s of the object-side face of the fourth spacer element, the interval EP34 between the third spacer element and the fourth spacer element in the direction of the optical axis, and the central thickness CT4 of the fourth lens on the optical axis satisfy: 3.60 ≤ D4s / (EP34 + CT4) ≤ 5.14. If D4s / (EP34 + CT4) is too large, the ratio of the thickness of the edge structural area of the fourth lens to the central thickness is too large, affecting the effective passage of light at the edge of the fourth lens and increasing the risk of stray light and aberrations. If D4s / (EP34 + CT4) is too small, the beam path in the edge region of the fourth lens is too compact, causing excessive squeezing of light at the edge of the fourth lens, resulting in the problem of edge necking during the forming process and increasing the manufacturing difficulty of the fourth lens. By restricting D4s / (EP34 + CT4) within a reasonable range, the ratio of the outer diameter of the object-side face of the fourth spacer element, the interval between the third spacer element and the fourth spacer element in the direction of the optical axis, and the central thickness of the fourth lens on the optical axis can be controlled, thereby controlling the thickness of the edge structural area of the fourth lens and the central thickness of the fourth lens, ensuring the processability of the fourth lens.

[0067] In this embodiment, the interval EP67 between the sixth spacer element and the seventh spacer element in the optical axis direction and the effective focal length f7 of the seventh lens satisfy: -1.11 ≤ EP67 / f7 × 10 ≤ -0.22, and the interval EP78 between the seventh spacer element and the eighth spacer element in the optical axis direction and the effective focal length f8 of the eighth lens satisfy: -1.91 ≤ EP78 / f8 × 10 ≤ -0.83. If the value of EP67 / f7 is too large, the interval between the sixth spacer element and the seventh spacer element in the optical axis direction becomes shorter relative to the effective focal length of the seventh lens, and the light path at the edge of the seventh lens becomes compact, increasing the probability of scattering and reflection of light in the edge region of the seventh lens, resulting in an increase in stray light phenomenon. If the value of EP67 / f7 × 10 is too small, the transmission path of light between the sixth lens and the seventh lens becomes longer, resulting in an increase in scattering of light in the air gap, and aberration will also occur when the light angle is large, reducing the color accuracy and clarity of imaging. By restricting EP67 / f7 × 10 within a reasonable range, by controlling the ratio of the interval between the sixth spacer element and the seventh spacer element in the optical axis direction and the effective focal length of the seventh lens, the thickness of the structural region of the sixth lens and the edge light range of the sixth lens are further controlled. While ensuring the optical parameters, the generation of stray light can be avoided and the image quality of the imaging surface can be ensured to be good.

[0068] At the same time, if the value of EP78 / f8 × 10 is too large, the space between the lens groups becomes too compact, reducing the freedom of light in the edge region of the seventh lens, resulting in an overly dense light path when the light transitions from the seventh lens to the eighth lens, and it is easy to generate disordered scattering, increasing stray light and ghosting phenomena. If the value of EP78 / f8 × 10 is too small, it causes an increase in reflection and scattering of light in the air gap, generating additional aberrations, and at the same time increasing the length and volume of the optical imaging device, affecting the portability and compactness of the optical imaging device. By restricting EP78 / f8 × 10 within a reasonable range, by controlling the ratio of the interval between the seventh spacer element and the eighth spacer element in the optical axis direction and the effective focal length of the eighth lens, the thickness of the structural region of the seventh lens and the edge light range of the seventh lens are further controlled. While ensuring the optical parameters, the imaging quality can be effectively improved.

[0069] In this embodiment, the on-axis distance TD from the object side surface of the first lens to the image side surface of the eighth lens, the on-axis distance TTL from the object side surface of the first lens to the imaging surface of the optical imaging device, and the inner diameter d0s of the object side end face of the lens barrel satisfy: 4.79 ≤ TD / TTL × d0s ≤ 5.83. If the value of TD / TTL × d0s is too large, the excessively large front-end size makes the assembly of the optical imaging device difficult and affects the overall design and functional layout of the optical imaging device. In addition, the excessively large TD / TTL ratio results in an excessively short back focal length of the optical imaging device, limiting the flexibility of the optical imaging device. If the value of TD / TTL × d0s is too small, the front-end size of the optical imaging device is too small, sacrificing the light-gathering ability. At the same time, the back focal distance is too long, affecting the direct transmission of light and reducing the effective utilization of light, reducing the brightness and contrast of the image, and increasing the risk of deterioration of the imaging quality in the edge region. By restricting TD / TTL × d0s within a reasonable range, the product of the ratio of the on-axis distance from the object side surface of the first lens to the image side surface of the eighth lens and the on-axis distance from the object side surface of the first lens to the imaging surface of the optical imaging device and the inner diameter of the object side end face of the lens barrel is controlled, thereby controlling the front-end size and back focal length of the optical imaging device. While ensuring that the front-end size of the optical imaging device is within the design requirements, the back focal length of the optical imaging device is ensured, and problems such as the protrusion of the rear lens or interference at the module end are avoided.

[0070] In this embodiment, the object side surface of the first lens is convex, the image side surface of the first lens is concave, the second lens has a positive optical power, the object side surface of the second lens is convex, the image side surface of the second lens is concave, the object side surface of the third lens is convex, the image side surface of the third lens is concave, the fourth lens has a positive optical power, the object side surface of the fourth lens is convex, the image side surface of the fourth lens is convex, the fifth lens has a negative optical power, the object side surface of the fifth lens is convex, the image side surface of the fifth lens is concave, the object side surface of the sixth lens is convex, the image side surface of the sixth lens is convex, the seventh lens has a negative optical power, and the object side surface of the eighth lens is concave.

[0071] By setting the object side of the first lens to be convex, it helps with the initial convergence of the light rays in the optical imaging device. The image side of the first lens is concave, which helps to adjust the path of the initial light rays and reduce aberration. The second lens has a positive focal power, which helps to focus the light rays that have passed through the first lens. The object side of the second lens is convex, which helps with the further convergence of the light rays. The image side of the second lens is concave, which helps to appropriately adjust the light path and diverge the light rays appropriately. The object side of the third lens is convex, which helps to further converge the light rays from the second lens. The image side of the third lens is concave, which is used to correct aberration and ensure the smooth transmission of light rays to the fourth lens. The fourth lens has a positive focal power, continuously converges the light rays, and is beneficial for improving the field of view of the optical imaging device. The object side of the fourth lens is convex, and the image side of the fourth lens is convex. The biconvex lens helps with the strong convergence of the light rays.

[0072] By setting the fifth lens to have a negative focal power, it helps to moderately diverge the light rays and avoid the excessive convergence of the light rays. The object side of the fifth lens is convex, which helps to converge the light rays from the fourth lens. The image side of the fifth lens is concave, further diverging the light rays and controlling aberration. The object side of the sixth lens is convex, and the image side of the sixth lens is convex. The biconvex lens helps with the convergence of the light rays. The seventh lens has a negative focal power, which is used to control the excessive convergence of the light rays and correct aberration. The object side of the eighth lens is concave. When the light rays reach the rear end of the optical imaging device, the light rays are adjusted once through the concave inwardly curved surface to optimize the imaging quality.

[0073] Second Embodiment

[0074] As Figures 1 to 23As shown, the number of lenses with optical power in the optical imaging device is eight. The optical imaging device includes a lens group, a spacer element group, and a barrel. From the object side to the image side of the optical imaging device, the lens group includes the first lens to the eighth lens arranged at intervals in sequence. The first lens has a positive optical power, the object side surface of the first lens is convex, and the image side surface of the first lens is concave. The second lens has a positive optical power, the object side surface of the second lens is convex, and the image side surface of the second lens is concave. The third lens has a negative optical power, the object side surface of the third lens is convex, and the image side surface of the third lens is concave. The fourth lens has a positive optical power, the object side surface of the fourth lens is convex, and the image side surface of the fourth lens is convex. The fifth lens has a negative optical power, the object side surface of the fifth lens is convex, and the image side surface of the fifth lens is concave. The sixth lens has a positive optical power, the object side surface of the sixth lens is convex, and the image side surface of the sixth lens is convex. The seventh lens has a negative optical power, the object side surface of the seventh lens is concave, and the eighth lens has a negative optical power, the object side surface of the eighth lens is concave; the spacer element group at least includes a first spacer element located between the first lens and the second lens and at least partially in contact with the image side surface of the first lens, a second spacer element located between the second lens and the third lens and at least partially in contact with the image side surface of the second lens, a third spacer element located between the third lens and the fourth lens and at least partially in contact with the image side surface of the third lens, a fourth spacer element located between the fourth lens and the fifth lens and at least partially in contact with the image side surface of the fourth lens, a fifth spacer element located between the fifth lens and the sixth lens and at least partially in contact with the image side surface of the fifth lens, a sixth spacer element located between the sixth lens and the seventh lens and at least partially in contact with the image side surface of the sixth lens, a seventh spacer element located between the seventh lens and the eighth lens and at least partially in contact with the image side surface of the seventh lens, and an eighth spacer element located on the image side of the eighth lens and at least partially in contact with the image side surface of the eighth lens; the lens group and the spacer element group are accommodated in the barrel; wherein, the radius of curvature R15 of the object side surface of the eighth lens, the interval EP78 between the seventh spacer element and the eighth spacer element along the optical axis direction, and the refractive index N8 of the eighth lens satisfy: 10.42 ≤ |R15| / EP78 × N8 ≤ 14.17; the interval EP78 between the seventh spacer element and the eighth spacer element along the optical axis direction, the maximum thickness CP8 of the eighth spacer element along the optical axis direction, and the central thickness CT8 of the eighth lens on the optical axis satisfy: 3.70 ≤ (EP78 + CP8) / CT8 ≤ 5.18.

[0075] The optical imaging device of the present application uses eight lenses with optical power, and the first lens to the eighth lens are arranged in sequence at intervals. In the optical imaging device of the present application, by restricting |R15| / EP78×N8 within a reasonable range, the product of the radius of curvature of the object side of the eighth lens, the interval between the seventh spacer element and the eighth spacer element in the optical axis direction, and the refractive index of the eighth lens can be controlled, thereby controlling the convexity degree of the eighth lens, avoiding the lens protruding outwards to the rear end of the lens barrel, and at the same time controlling the light range of the outer field of view of the eighth lens, avoiding the generation of redundant stray light in the optical imaging device. However, the large distance between the seventh spacer element and the eighth spacer element cannot effectively control the stray light problem, especially in the air gap between the lens groups and the lens edge region. By controlling (EP78+CP8) / CT8 within a reasonable range, the shape of the rear end of the optical imaging device can be controlled, and further, the stray light in the edge region of the eighth lens can be controlled more effectively. By adjusting the thickness of the eighth lens, the stray light caused by the uneven edge shape or thickness of the eighth lens can be reduced. It should be noted that other conditional expressions in the above embodiments are also included in this embodiment, which will not be elaborated here one by one.

[0076] Optionally, the above optical imaging device may further include a protective glass for protecting the photosensitive element located on the imaging surface.

[0077] The optical imaging device in the present application can use multiple lenses, such as the eight lenses described above. In the present 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 astigmatism aberration. After using an aspherical lens, the aberration that appears during imaging can be eliminated as much as possible, thereby improving the imaging quality.

[0078] However, those skilled in the art should understand that without departing from the technical solutions claimed in the present application, the number of lenses constituting the optical imaging device can be changed to obtain the various results and advantages described in this specification. For example, although the eight lenses are described as an example in the embodiment, the optical imaging device is not limited to including eight lenses. If necessary, the optical imaging device may further include other numbers of lenses.

[0079] Figure 1 A schematic diagram of the dimension marking of an optical imaging device of the present application is shown, Figure 1 Parameters such as d1s, D2s, L, EP34, etc. are marked in it to clearly and intuitively understand the meaning of the parameters. For the convenience of describing the optical imaging device and the surface shape of the specific lens, these parameters will no longer be shown in the drawings when describing specific embodiments later.

[0080] The following further describes, with reference to the accompanying drawings, examples of the specific surface shape and parameters of the optical imaging device applicable to the above embodiments.

[0081] It should be noted that any one of the following Examples 1 to 9 is applicable to all embodiments of the present application.

[0082] Example 1

[0083] As Figure 2 shown, the optical imaging device of Example 1 of the present application is described. Figure 2 The schematic structural diagram of the optical imaging device of Example 1 is shown.

[0084] As Figure 2 shown, the optical imaging device sequentially includes, from the object side to the image side: a first lens E1, a first spacer element P1, a second lens E2, a second spacer element P2, a third lens E3, a third spacer element P3, a fourth lens E4, a fourth spacer element P4, a fifth lens E5, a fifth spacer element P5, a sixth lens E6, a sixth spacer element P6, a seventh lens E7, a seventh spacer element P7, an eighth lens E8, and an eighth spacer element P8.

[0085] In this embodiment, the first lens E1 has a positive optical power. The object side surface S1 of the first lens is convex, and the image side surface S2 of the first lens is concave. The second lens E2 has a positive optical power. The object side surface S3 of the second lens is convex, and the image side surface S4 of the second lens is concave. The third lens E3 has a negative optical power. The object side surface S5 of the third lens is convex, and the image side surface S6 of the third lens is concave. The fourth lens E4 has a positive optical power. The object side surface S7 of the fourth lens is convex, and the image side surface S8 of the fourth lens is convex. The fifth lens E5 has a negative optical power. The object side surface S9 of the fifth lens is convex, and the image side surface S10 of the fifth lens is concave. The sixth lens E6 has a positive optical power. The object side surface S11 of the sixth lens is convex, and the image side surface S12 of the sixth lens is convex. The seventh lens E7 has a negative optical power. The object side surface S13 of the seventh lens is concave, and the image side surface S14 of the seventh lens is convex. The eighth lens E8 has a negative optical power. The object side surface S15 of the eighth lens is concave, and the image side surface S16 of the eighth lens is concave. The optical imaging device also has a filter, and the filter has an object side surface S17 of the filter and an image side surface S18 of the filter. The light from the object surface passes through S1 to S18 and reaches the imaging surface IMG.

[0086] Table 2 shows the basic structural parameters of the optical imaging device of Example 1, where the units of the radius of curvature, thickness / distance, effective radius, and focal length are all millimeters (mm).

[0087] Table 2

[0088]

[0089] In Embodiment 1, the object side and the image side of any one of the first lens E1 to the eighth lens E8 are aspherical surfaces. The surface profiles of the aspherical lenses can be defined by, but are not limited to, the following aspherical formula:

[0090] Formula (1);

[0091] Where x is the sagitta, the distance from the vertex of the aspherical surface when the aspherical surface is at a position with a height of h along the optical axis; c is the paraxial curvature of the aspherical surface, c = 1 / R (i.e., the paraxial curvature c is the reciprocal of the radius of curvature R in Table 2 above); k is the conic coefficient; Ai is the correction coefficient of the i-th order of the aspherical surface. Table 3 below gives the higher-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, and A20 that can be used for the aspherical surfaces S1 - S16 in Embodiment 1.

[0092] Table 3 shows the higher-order coefficients that can be used for the aspherical surfaces in the embodiments. Among them, the surface profiles of the aspherical surfaces can be defined by Formula (1) given in Embodiment 1 above. In this embodiment, the object side and the image side of the first lens to the eighth lens are both aspherical surfaces.

[0093] Table 3

[0094]

[0095] Figure 5 shows the longitudinal chromatic aberration curve of the optical imaging device of Embodiment 1, which represents the degree to which the focal points of light rays of different wavelengths do not completely coincide. Figure 6 shows the astigmatism curve of the optical imaging device of Embodiment 1, which represents the curvature of the meridional image plane and the curvature of the sagittal image plane. Figure 7 shows the distortion curve of the optical imaging device of Embodiment 1, which represents the distortion magnitude values corresponding to different field angles.

[0096] According to Figures 5 to 7 it can be seen that the optical imaging device given in Embodiment 1 can achieve good imaging quality.

[0097] Embodiment 2

[0098] As Figure 3 shown, the optical imaging device of Embodiment 2 of the present application is described. The difference from Embodiment 1 is that the distances and thicknesses between the spacer elements, lenses, lens barrels P0, etc. are different.

[0099] Figure 3The structural schematic diagram of the optical imaging device according to the second embodiment is shown. For the sake of simplicity, some descriptions similar to those in the first embodiment will be omitted. In this embodiment, the structural area of the third lens is thickened, providing a tighter support for the front lens.

[0100] Embodiment Three

[0101] As Figure 4 shown, the optical imaging device according to the third embodiment of the present application is described. The difference from the first embodiment lies in the different distances and thicknesses between each spacer element, lens, barrel P0, etc.

[0102] Figure 4 The structural schematic diagram of the optical imaging device according to the third embodiment is shown. For the sake of simplicity, some descriptions similar to those in the first embodiment will be omitted. In this embodiment, the object side of the fourth spacer element is fastened to the fourth lens, and the image side of the fourth spacer element is fastened to the fifth lens, improving the stability of the relatively thick fourth spacer element in abutting against the front and rear lenses and ensuring the stable assembly of the large-aperture difference transition region from the fourth lens to the fifth lens.

[0103] Embodiment Four

[0104] As Figure 8 shown, the optical imaging device according to the fourth embodiment of the present application is described. Figure 8 The structural schematic diagram of the optical imaging device according to the fourth embodiment is shown.

[0105] As Figure 8 shown, the optical imaging device sequentially includes, from the object side to the image side: a first lens E1, a first spacer element P1, a second lens E2, a second spacer element P2, a third lens E3, a third spacer element P3, a fourth lens E4, a fourth spacer element P4, a fifth lens E5, a fifth spacer element P5, a sixth lens E6, a sixth spacer element P6, a seventh lens E7, a seventh spacer element P7, an eighth lens E8, and an eighth spacer element P8.

[0106] In this embodiment, the first lens E1 has a positive optical power. The object side S1 of the first lens is convex, and the image side S2 of the first lens is concave. The second lens E2 has a positive optical power. The object side S3 of the second lens is convex, and the image side S4 of the second lens is concave. The third lens E3 has a negative optical power. The object side S5 of the third lens is convex, and the image side S6 of the third lens is concave. The fourth lens E4 has a positive optical power. The object side S7 of the fourth lens is convex, and the image side S8 of the fourth lens is convex. The fifth lens E5 has a negative optical power. The object side S9 of the fifth lens is convex, and the image side S10 of the fifth lens is concave. The sixth lens E6 has a positive optical power. The object side S11 of the sixth lens is convex, and the image side S12 of the sixth lens is convex. The seventh lens E7 has a negative optical power. The object side S13 of the seventh lens is concave, and the image side S14 of the seventh lens is concave. The eighth lens E8 has a negative optical power. The object side S15 of the eighth lens is concave, and the image side S16 of the eighth lens is convex. The optical imaging device further includes a filter, which has an object side S17 and an image side S18 of the filter. Light rays from the object plane pass through S1 to S18 and reach the imaging plane IMG.

[0107] Table 4 shows the basic structural parameters of the optical imaging device of Embodiment 4, where the units of the radius of curvature, thickness / distance, effective radius, and focal length are all millimeters (mm).

[0108] Table 4

[0109]

[0110] Table 5 shows the high-order term coefficients of the aspherical mirrors that can be used in each of the embodiments. The surface profiles of the aspherical surfaces can be defined by Formula (1) given in Embodiment 1 above. In this embodiment, the object sides and image sides of the first lens to the eighth lens are all aspherical surfaces.

[0111] Table 5

[0112]

[0113] Figure 11 Shows the longitudinal chromatic aberration curve of the optical imaging device of Embodiment 4, which represents the degree to which the focal points of light rays of different wavelengths do not completely coincide. Figure 12 Shows the astigmatism curve of the optical imaging device of Embodiment 4, which represents the curvature of the meridional image plane and the curvature of the sagittal image plane. Figure 13 Shows the distortion curve of the optical imaging device of Embodiment 4, which represents the distortion magnitude values corresponding to different field angles.

[0114] According to Figures 11 to 13 It can be seen that the optical imaging device given in Embodiment 4 can achieve good imaging quality.

[0115] Example 5

[0116] As Figure 9 shown, an optical imaging device according to Example 5 of the present application is described. The difference from Example 4 lies in the different distances and thicknesses between each spacer element, lens, lens barrel P0, etc.

[0117] Figure 9 The structural schematic diagram of the optical imaging device according to Example 5 is shown. For the sake of brevity, some descriptions similar to those in Example 4 will be omitted. In this embodiment, the structural area of the fifth lens is shortened, which is beneficial to the miniaturization of the optical imaging device.

[0118] Example 6

[0119] As Figure 10 shown, an optical imaging device according to Example 6 of the present application is described. The difference from Example 4 lies in the different distances and thicknesses between each spacer element, lens, lens barrel P0, etc.

[0120] Figure 10 The structural schematic diagram of the optical imaging device according to Example 6 is shown. For the sake of brevity, some descriptions similar to those in Example 4 will be omitted. In this embodiment, the object side of the fourth spacer element is fastened to the fourth lens, and the image side of the fourth spacer element is fastened to the fifth lens, which improves the stability of the relatively thick fourth spacer element bearing against the front and rear lenses and ensures the stable assembly of the large-aperture difference transition region from the fourth lens to the fifth lens. In addition, the wall thickness of the lens barrel thickens in the transition region between the front and rear lens groups, providing a stable support for the smooth transition between the front and rear lens groups, providing a better light-shielding effect, reducing the reflection of light on the inner wall of the lens barrel, thereby effectively suppressing stray light and improving the imaging quality.

[0121] Example 7

[0122] As Figure 14 shown, an optical imaging device according to Example 7 of the present application is described. Figure 14 The structural schematic diagram of the optical imaging device according to Example 7 is shown.

[0123] As Figure 14 shown, the optical imaging device sequentially includes, from the object side to the image side: a first lens E1, a first spacer element P1, a second lens E2, a second spacer element P2, a third lens E3, a third spacer element P3, a fourth lens E4, a fourth spacer element P4, a fifth lens E5, a fifth spacer element P5, a sixth lens E6, a sixth spacer element P6, a seventh lens E7, a seventh spacer element P7, an eighth lens E8, and an eighth spacer element P8.

[0124] In this embodiment, the first lens E1 has a positive optical power. The object side surface S1 of the first lens is convex, and the image side surface S2 of the first lens is concave. The second lens E2 has a positive optical power. The object side surface S3 of the second lens is convex, and the image side surface S4 of the second lens is concave. The third lens E3 has a negative optical power. The object side surface S5 of the third lens is convex, and the image side surface S6 of the third lens is concave. The fourth lens E4 has a positive optical power. The object side surface S7 of the fourth lens is convex, and the image side surface S8 of the fourth lens is convex. The fifth lens E5 has a negative optical power. The object side surface S9 of the fifth lens is convex, and the image side surface S10 of the fifth lens is concave. The sixth lens E6 has a positive optical power. The object side surface S11 of the sixth lens is convex, and the image side surface S12 of the sixth lens is convex. The seventh lens E7 has a negative optical power. The object side surface S13 of the seventh lens is concave, and the image side surface S14 of the seventh lens is convex. The eighth lens E8 has a negative optical power. The object side surface S15 of the eighth lens is concave, and the image side surface S16 of the eighth lens is convex. The optical imaging device further includes a filter, which has an object side surface S17 of the filter and an image side surface S18 of the filter. The light rays from the object surface pass through S1 to S18 and reach the imaging surface IMG.

[0125] Table 6 shows the basic structural parameters of the optical imaging device of Embodiment 7, where the units of the radius of curvature, thickness / distance, effective radius, and focal length are all millimeters (mm).

[0126] Table 6

[0127]

[0128] Table 7 shows the high-order term coefficients of the aspherical mirror surfaces that can be used in each of the embodiments. The surface profiles of the aspherical surfaces can be defined by the formula (1) given in Embodiment 1 above. In this embodiment, the object side surfaces and image side surfaces of the first lens to the eighth lens are all aspherical surfaces.

[0129] Table 7

[0130]

[0131] Figure 17 shows the longitudinal chromatic aberration curve of the optical imaging device of Embodiment 7, which represents the degree to which the focal points of light rays of different wavelengths do not completely coincide. Figure 18 shows the astigmatism curve of the optical imaging device of Embodiment 7, which represents the meridional image plane curvature and the sagittal image plane curvature. Figure 19 shows the distortion curve of the optical imaging device of Embodiment 7, which represents the distortion magnitude values corresponding to different field angles.

[0132] According to Figures 17 to 19 it can be seen that the optical imaging device given in Embodiment 7 can achieve good imaging quality.

[0133] Example 8

[0134] As Figure 15 shown, an optical imaging device according to Example 8 of the present application is described. The difference from Example 7 lies in the different distances and thicknesses between each spacer element, lens, barrel P0, etc.

[0135] Figure 15 The structural schematic diagram of the optical imaging device according to Example 8 is shown. For the sake of brevity, some descriptions similar to those in Example 7 will be omitted. In this embodiment, the fifth lens, the sixth lens, and the seventh lens are sequentially buckled and arranged, providing a more compact support for the front and rear end lens groups.

[0136] Example 9

[0137] As Figure 16 shown, an optical imaging device according to Example 9 of the present application is described. The difference from Example 7 lies in the different distances and thicknesses between each spacer element, lens, barrel P0, etc.

[0138] Figure 16 The structural schematic diagram of the optical imaging device according to Example 9 is shown. For the sake of brevity, some descriptions similar to those in Example 7 will be omitted. In this embodiment, the object side of the fourth spacer element is buckled with the fourth lens, and the image side of the fourth spacer element is buckled with the fifth lens, improving the stability of the relatively thick fourth spacer element bearing against the front and rear lenses and ensuring the assembly stability of the large-aperture difference transition region from the fourth lens to the fifth lens.

[0139] In summary, Examples 1 to 9 of the optical imaging device respectively satisfy the relationships shown in Table 8.

[0140] Table 8

[0141]

[0142] Table 9 gives the effective focal lengths f1 to f8, etc. of the lenses of the optical imaging devices according to Examples 1 to 9, in mm.

[0143] Table 9

[0144]

[0145] Table 10 gives some structural parameters of the optical imaging devices according to Examples 1 to 9, in mm.

[0146] Table 10

[0147]

[0148] Obviously, the embodiments described above are only some of the embodiments of the present invention, not all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0149] It should be noted that the terms used herein are for the purpose of describing specific embodiments only 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 forms are also intended to include the plural forms. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they specify the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0150] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present application described herein can be implemented in an order different from those illustrated or described herein.

[0151] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An optical imaging device, characterized in that: The optical imaging device has eight lenses with optical power, and the optical imaging device includes: A lens group, wherein the lens group comprises a first lens to an eighth lens arranged in sequence from the object side to the image side of the optical imaging device, wherein the first lens has positive focal power, the object side surface of the first lens is convex, and the image side surface of the first lens is concave, the second lens has positive focal power, the object side surface of the second lens is convex, and the image side surface of the second lens is concave, the third lens has negative focal power, the object side surface of the third lens is convex, and the image side surface of the third lens is concave, the fourth lens has positive focal power, the object side surface of the fourth lens is convex, and the image side surface of the fourth lens is convex, the fifth lens has negative focal power, the object side surface of the fifth lens is convex, and the image side surface of the fifth lens is concave, the sixth lens has positive focal power, the object side surface of the sixth lens is convex, and the image side surface of the sixth lens is convex, the seventh lens has negative focal power, the object side surface of the seventh lens is concave, the eighth lens has negative focal power, and the object side surface of the eighth lens is concave; a spacer element group, wherein the spacer element group includes at least a first spacer element located between the first lens and the second lens and at least partially in contact with the image side surface of the first lens, a second spacer element located between the second lens and the third lens and at least partially in contact with the image side surface of the second lens, a third spacer element located between the third lens and the fourth lens and at least partially in contact with the image side surface of the third lens, a fourth spacer element located between the fourth lens and the fifth lens and at least partially in contact with the image side surface of the fourth lens, a fifth spacer element located between the fifth lens and the sixth lens and at least partially in contact with the image side surface of the fifth lens, a sixth spacer element located between the sixth lens and the seventh lens and at least partially in contact with the image side surface of the sixth lens, a seventh spacer element located between the seventh lens and the eighth lens and at least partially in contact with the image side surface of the seventh lens, and an eighth spacer element located on the image side of the eighth lens and at least partially in contact with the image side surface of the eighth lens; a lens barrel, wherein the lens group and the spacer element group are accommodated in the lens barrel; Wherein, the distance L from the object side end surface of the lens barrel to the image side end surface of the lens barrel along the direction of the optical axis of the optical imaging device and the sum ∑CP of the thicknesses of all the spacer elements in the spacer element group satisfy: 3.42≤L / ∑CP≤4.64; The curvature radius R8 of the image side surface of the fourth lens, the curvature radius R9 of the object side surface of the fifth lens, and the interval EP45 between the fourth spacing element and the fifth spacing element along the optical axis satisfy: -2.73≤(R8+R9) / EP45≤-1.52; The combined focal length f45 of the fourth lens and the fifth lens, the inner diameter d5s of the object side surface of the fifth spacing element, and the inner diameter d3s of the object side surface of the third spacing element satisfy: 5.40≤f45 / (d5s-d3s)≤7.

62.

2. The optical imaging device according to claim 1, characterized in that: The entrance pupil diameter EPD of the optical imaging device, the outer diameter D1s of the object side surface of the first spacing element, and the inner diameter d1s of the object side surface of the first spacing element satisfy the following: 1.91≤EPD / (D1s-d1s)≤2.

34.

3. The optical imaging device according to claim 1, characterized in that: An effective focal length f7 of the seventh lens, an effective focal length f8 of the eighth lens, and an inner diameter d7s of the object side surface of the seventh spacing element satisfy the following: 3.23≤|f7+f8| / d7s≤10.

40.

4. The optical imaging device according to claim 1, characterized in that: An inner diameter d4m of the image side surface of the fourth spacer element, an inner diameter d4s of the object side surface of the fourth spacer element, and a center thickness CT4 of the fourth lens on the optical axis satisfy: -0.10≤(d4m-d4s) / CT4≤1.

70.

5. The optical imaging device according to claim 1, characterized in that: The outer diameter D6s of the object side surface of the sixth spacer element, the interval EP56 between the fifth spacer element and the sixth spacer element along the optical axis, and the center thickness CT6 of the sixth lens on the optical axis satisfy the following: 3.37≤D6s / (EP56+CT6)≤5.

47.

6. The optical imaging device according to claim 1, characterized in that: A curvature radius R7 of the object side surface of the fourth lens and a curvature radius R8 of the image side surface of the fourth lens satisfy: -4.50≤R7 / R8≤-3.52; an outer diameter D3m of the image side surface of the third spacing element and an outer diameter D4s of the object side surface of the fourth spacing element satisfy: 9.68≤D3m / D4s×10≤11.

12.

7. The optical imaging device according to claim 1, characterized in that: An outer diameter D5m of the image side surface of the fifth spacer element, an inner diameter d5m of the image side surface of the fifth spacer element, and a curvature radius R11 of the object side surface of the sixth lens satisfy the following: 0.07≤(D5m+d5m) / R11≤0.

65.

8. The optical imaging device according to claim 1, characterized in that: The curvature radius R15 of the object side surface of the eighth lens, the interval EP78 between the seventh spacer element and the eighth spacer element along the optical axis, and the refractive index N8 of the eighth lens satisfy the following: 10.42≤|R15| / EP78×N8≤14.

17.

9. The optical imaging device according to claim 1, characterized in that: An interval EP45 between the fourth spacing element and the fifth spacing element along the direction of the optical axis and an interval EP56 between the fifth spacing element and the sixth spacing element along the direction of the optical axis satisfy the following: 0.55≤EP45 / EP56≤1.

18.

10. The optical imaging device according to any one of claims 1 to 9, characterized in that: An outer diameter D4s of the object side surface of the fourth spacer element, an inner diameter d4s of the object side surface of the fourth spacer element, and a curvature radius R8 of the image side surface of the fourth lens satisfy the following relationship: 0.08≤(D4s-d4s) / |R8|≤0.

52.

11. The optical imaging device according to any one of claims 1 to 9, characterized in that: The distance L from the object side end face of the lens barrel to the image side end face of the lens barrel along the direction of the optical axis of the optical imaging device, the sum ∑AT of the air spacing of any adjacent lenses from the first lens to the eighth lens on the optical axis, the center thickness CT7 of the seventh lens on the optical axis, and the center thickness CT8 of the eighth lens on the optical axis satisfy the following conditions: 4.38≤(L-∑AT) / (CT7+CT8)≤6.

15.

12. The optical imaging device according to any one of claims 1 to 9, characterized in that: The outer diameter D4s of the object side of the fourth spacer element, the interval EP34 between the third spacer element and the fourth spacer element along the optical axis, and the center thickness CT4 of the fourth lens on the optical axis satisfy: 3.60≤D4s / (EP34+CT4)≤5.

14.

13. The optical imaging device according to any one of claims 1 to 9, characterized in that: The interval EP67 between the sixth spacing element and the seventh spacing element along the direction of the optical axis and the effective focal length f7 of the seventh lens satisfy: -1.11≤EP67 / f7×10≤-0.22; the interval EP78 between the seventh spacing element and the eighth spacing element along the direction of the optical axis and the effective focal length f8 of the eighth lens satisfy: -1.91≤EP78 / f8×10≤-0.

83.

14. The optical imaging device according to any one of claims 1 to 9, characterized in that: The axial distance TD from the object side surface of the first lens to the image side surface of the eighth lens, the axial distance TTL from the object side surface of the first lens to the imaging surface of the optical imaging device, and the inner diameter d0s of the object side end surface of the lens barrel satisfy the following conditions: 4.79≤TD / TTL×d0s≤5.83.

Images