Optical imaging device

Abstract

The application provides an optical imaging device. The optical imaging device comprises a lens barrel, a lens group and a spacer element group, the lens group is composed of eight lenses, and the lenses are sequentially arranged from an object side to an image side as a first lens with positive refractive power, a second lens with refractive power, a third lens with refractive power, a fourth lens with negative refractive power, a fifth lens with refractive power, a sixth lens with refractive power, a seventh lens with refractive power and an eighth lens with negative refractive power; 5.19 <= L / CP <= 10.92 is met; 13.76 <= R11 / R12*V6 <= 15.93 is met; and 2.68 <= (EP56+CP6) / CT6 <= 3.90 is met. The application solves the problem that the tail end lens of the eight-piece optical imaging device in the prior art is made of high dispersion material, the size of the tail end lens is unreasonable, and stress concentration and deformation occur during assembly.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of optical imaging technology, and in particular, to an optical imaging device. BACKGROUND

[0002] With the rapid development of technology, consumers have higher requirements for optical imaging devices mounted on portable smart electronic devices, especially optical imaging devices mounted on smart phones. In order to meet the high-definition camera needs of users in daily life, the number of lens pieces of optical imaging devices is increasing, especially the application of eight-piece optical imaging devices is becoming more and more widespread. However, the lightweight design of smart phones limits the size of optical imaging devices, which makes the eight-piece optical imaging device face many challenges in design and assembly.

[0003] In the existing design of eight-piece optical imaging devices, in order to optimize the dispersion correction of the optical imaging device under the premise of meeting the compact structure, the tail end lens usually adopts high dispersion material, which limits the structure size of the tail end lens, and easily leads to stress concentration and deformation of the tail end lens during assembly, thereby affecting the assembly stability of the optical imaging device.

[0004] That is, the eight-piece optical imaging device in the prior art has the problem that the tail end lens is selected to be a high dispersion material, which makes the size of the tail end lens unreasonable, and further leads to stress concentration and deformation during assembly. SUMMARY

[0005] The main purpose of the present application is to provide an optical imaging device to solve the problem that the eight-piece optical imaging device in the prior art selects the tail end lens to be a high dispersion material, which makes the size of the tail end lens unreasonable, and further leads to stress concentration and deformation during assembly.

[0006] In order to achieve the above object, according to one aspect of the present application, there is provided an optical imaging device, comprising a lens barrel and a lens group and a spacer element group arranged in the lens barrel, the lens group consisting of eight lenses arranged in order from an object side to an image side as a first lens having a positive refractive power, a second lens having a refractive power, a third lens having a refractive power, a fourth lens having a negative refractive power, a fifth lens having a refractive power, a sixth lens having a refractive power, a seventh lens having a refractive power, and an eighth lens having a negative refractive power; the object side surface of the first lens is a convex surface, the image side surface of the fifth lens is a convex surface, the object side surface of the sixth lens is a concave surface, the image side surface of the sixth lens is a convex surface, and the image side surface of the eighth lens is a concave surface; each of two adjacent lenses among the first to eighth lenses has an air gap on an optical axis of the optical imaging device; the spacer element group comprises a first spacer element arranged between the first lens and the second lens and partially abutting against the image side surface of the first lens, a second spacer element arranged between the second lens and the third lens and partially abutting against the image side surface of the second lens, a third spacer element arranged between the third lens and the fourth lens and partially abutting against the image side surface of the third lens, a fourth spacer element arranged between the fourth lens and the fifth lens and partially abutting against the image side surface of the fourth lens, a fifth spacer element arranged between the fifth lens and the sixth lens and partially abutting against the image side surface of the fifth lens, a sixth spacer element arranged between the sixth lens and the seventh lens and partially abutting against the image side surface of the sixth lens, a seventh spacer element arranged between the seventh lens and the eighth lens and partially abutting against the image side surface of the seventh lens, and an eighth spacer element arranged on the image side of the eighth lens and partially abutting against the image side surface of the eighth lens; the maximum axial height L of the lens barrel and the sum ∑CP of the axial thicknesses of all the spacer elements of the optical imaging device satisfy: 5.19≤L / ∑CP≤10.92; the radius of curvature R11 of the object side surface of the sixth lens, the radius of curvature R12 of the image side surface of the sixth lens, and the Abbe number V6 of the sixth lens satisfy: 13.76≤R11 / R12×V6≤15.93; the interval distance EP56 on the optical axis between the image side surface of the fifth spacer element and the object side surface of the sixth spacer element, the sum ∑CP6 of the axial thicknesses of all the spacer elements between the sixth lens and the seventh lens, and the central thickness CT6 of the sixth lens on the optical axis satisfy: 2.68≤(EP56+∑CP6) / CT6≤3.90.

[0007] According to another aspect of the present application, there is provided an optical imaging device, comprising a lens barrel and a lens group and a spacer element group arranged in the lens barrel, the lens group consisting of eight lenses arranged in order from an object side to an image side as a first lens having a positive refractive power, a second lens having a refractive power, a third lens having a refractive power, a fourth lens having a negative refractive power, a fifth lens having a refractive power, a sixth lens having a refractive power, a seventh lens having a refractive power, and an eighth lens having a negative refractive power; the object side surface of the first lens is convex, the image side surface of the fifth lens is convex, the object side surface of the sixth lens is concave, the image side surface of the sixth lens is convex, and the image side surface of the eighth lens is concave; each of two adjacent lenses among the first lens to the eighth lens has an air gap on an optical axis of the optical imaging device; the spacer element group comprises a first spacer element arranged between the first lens and the second lens and partially abutting against the image side surface of the first lens, a second spacer element arranged between the second lens and the third lens and partially abutting against the image side surface of the second lens, a third spacer element arranged between the third lens and the fourth lens and partially abutting against the image side surface of the third lens, a fourth spacer element arranged between the fourth lens and the fifth lens and partially abutting against the image side surface of the fourth lens, a fifth spacer element arranged between the fifth lens and the sixth lens and partially abutting against the image side surface of the fifth lens, a sixth spacer element arranged between the sixth lens and the seventh lens and partially abutting against the image side surface of the sixth lens, a seventh spacer element arranged between the seventh lens and the eighth lens and partially abutting against the image side surface of the seventh lens, and an eighth spacer element arranged on the image side of the eighth lens and partially abutting against the image side surface of the eighth lens; the maximum axial height L of the lens barrel and the effective focal length f of the optical imaging device satisfy: 1.40≤L / f≤1.53; the radius of curvature R11 of the object side surface of the sixth lens, the radius of curvature R12 of the image side surface of the sixth lens, and the Abbe number V6 of the sixth lens satisfy: 13.76≤R11 / R12×V6≤15.93; the sixth lens has a negative refractive power, the effective focal length f6 of the sixth lens, the interval distance EP56 on the optical axis between the image side surface of the fifth spacer element and the object side surface of the sixth spacer element, and the central thickness CT6 of the sixth lens on the optical axis satisfy: 4.89≤|f6| / (EP56+CT6)≤8.06.

[0008] According to another aspect of the present application, there is provided an optical imaging device, comprising a lens barrel and a lens group and a spacer element group arranged in the lens barrel, the lens group consisting of eight lenses arranged in order from an object side to an image side as a first lens having a positive refractive power, a second lens having a refractive power, a third lens having a refractive power, a fourth lens having a negative refractive power, a fifth lens having a refractive power, a sixth lens having a refractive power, a seventh lens having a refractive power, and an eighth lens having a negative refractive power; the object side surface of the first lens is convex, the image side surface of the fifth lens is convex, the object side surface of the sixth lens is concave, the image side surface of the sixth lens is convex, and the image side surface of the eighth lens is concave; each of two adjacent lenses among the first lens to the eighth lens has an air gap on an optical axis of the optical imaging device; the spacer element group comprises a first spacer element arranged between the first lens and the second lens and partially abutting against the image side surface of the first lens, a second spacer element arranged between the second lens and the third lens and partially abutting against the image side surface of the second lens, a third spacer element arranged between the third lens and the fourth lens and partially abutting against the image side surface of the third lens, a fourth spacer element arranged between the fourth lens and the fifth lens and partially abutting against the image side surface of the fourth lens, a fifth spacer element arranged between the fifth lens and the sixth lens and partially abutting against the image side surface of the fifth lens, a sixth spacer element arranged between the sixth lens and the seventh lens and partially abutting against the image side surface of the sixth lens, a seventh spacer element arranged between the seventh lens and the eighth lens and partially abutting against the image side surface of the seventh lens, and an eighth spacer element arranged on the image side of the eighth lens and partially abutting against the image side surface of the eighth lens; a maximum axial height L of the lens barrel and an effective focal length f of the optical imaging device satisfy: 1.40≤L / f≤1.53; a radius of curvature R11 of the object side surface of the sixth lens, a radius of curvature R12 of the image side surface of the sixth lens, and an Abbe number V6 of the sixth lens satisfy: 13.76≤R11 / R12×V6≤15.93; a separation distance EP56 of the image side surface of the fifth spacer element to the object side surface of the sixth spacer element on the optical axis, a central thickness CT6 of the sixth lens on the optical axis, and the radius of curvature R11 of the object side surface of the sixth lens satisfy: -9.58≤EP56 / CT6×R11≤-5.86.

[0009] Further, the object side surface of the fourth lens is convex, an inner diameter d3m of the image side surface of the third spacer element, an outer diameter D3m of the image side surface of the third spacer element, and a radius of curvature R7 of the object side surface of the fourth lens satisfy: 0.90≤(d3m+D3m) / R7≤1.63.

[0010] Further, an inner diameter d8s of the object side surface of the eighth spacer element, a radius of curvature R15 of the object side surface of the eighth lens, and a radius of curvature R16 of the image side surface of the eighth lens satisfy: -1.90≤d8s / (R15+R16)≤1.25.

[0011] Further, a separation distance EP23 on the optical axis between the image side surface of the second separation element to the object side surface of the third separation element and a separation distance EP34 on the optical axis between the image side surface of the third separation element to the object side surface of the fourth separation element satisfy: 0.64 ≤ EP23 / EP34 ≤ 1.42.

[0012] Further, an outer diameter D7m of the image side surface of the seventh separation element, an inner diameter d8s of the object side surface of the eighth separation element and a central thickness CT8 on the optical axis of the eighth lens satisfy: 0.12 ≤ (D7m - d8s) / CT8 ≤ 1.34.

[0013] Further, a maximum axial height L of the lens barrel, a sum ∑AT of air gaps on the optical axis of adjacent two lenses among the first to eighth lenses and an air separation T34 on the optical axis of the third and fourth lenses satisfy: 8.44 ≤ (L-∑AT) / T34 ≤ 10.43.

[0014] Further, the object side surface of the seventh lens is a convex surface, an outer diameter D6m of the image side surface of the sixth separation element, an inner diameter d6m of the image side surface of the sixth separation element and a curvature radius R13 of the object side surface of the seventh lens satisfy: 0.17 ≤ (D6m - d6m) / R13 ≤ 1.61.

[0015] Further, an outer diameter D0s of the object side end surface of the lens barrel, an inner diameter d1s of the object side surface of the first separation element and a central thickness CT1 on the optical axis of the first lens satisfy: 6.78 ≤ (D0s - d1s) / CT1 ≤ 7.95.

[0016] Further, the sixth lens has a negative refractive power, an effective focal length f6 of the sixth lens, a separation distance EP56 on the optical axis between the image side surface of the fifth separation element to the object side surface of the sixth separation element and a central thickness CT6 on the optical axis of the sixth lens satisfy: 4.89 ≤ |f6| / (EP56 + CT6) ≤ 8.06.

[0017] Further, the second lens has a positive refractive power, an effective focal length f2 of the second lens, a refractive index N2 of the second lens and an inner diameter d2m of the image side surface of the second separation element satisfy: 2.88 ≤ f2 × N2 / d2m ≤ 4.48.

[0018] Further, a sum ∑EP of a distance from the object side end surface of the lens barrel to the object side surface of the first separation element and a separation distance on the optical axis of adjacent two separation elements among the first to eighth separation elements and a separation distance EP12 on the optical axis between the image side surface of the first separation element to the object side surface of the second separation element satisfy: 10.49 ≤ ∑EP / EP12 ≤ 13.27.

[0019] Further, the image-side surface of the seventh lens is a concave surface, and a curvature radius R14 of the image-side surface of the seventh lens and an inner diameter d7s of the object-side surface of the seventh spacer element satisfy: 0.93≤R14 / d7s≤1.71.

[0020] Further, a curvature radius R10 of the image-side surface of the fifth lens, an outer diameter D5m of the image-side surface of the fifth spacer element, and a refractive index N5 of the fifth lens satisfy: -2.47≤R10×N5 / D5m≤-1.68.

[0021] Further, an interval distance EP78 on the optical axis from the image-side surface of the seventh spacer element to the object-side surface of the eighth spacer element, an axial thickness CP8 of the eighth spacer element, and a central thickness CT8 of the eighth lens on the optical axis satisfy: 2.04≤(EP78+CP8) / CT8≤2.71.

[0022] Further, the spacer element group further includes one or two auxiliary spacer elements disposed between the sixth spacer element and the seventh lens, and a third auxiliary spacer element disposed between the third spacer element and the fourth lens.

[0023] Further, the third lens has a negative refractive power, the fifth lens has a positive refractive power, and the seventh lens has a positive refractive power; the image-side surface of the first lens is a concave surface, the object-side surface of the second lens is a convex surface, the object-side surface of the third lens is a convex surface, the image-side surface of the third lens is a concave surface, the image-side surface of the fourth lens is a concave surface, and the object-side surface of the fifth lens is a convex surface.

[0024] Applying the technical solution of this invention, the optical imaging device of this application comprises a lens barrel and eight lenses and multiple spacer elements disposed within the lens barrel. By reasonably setting the first lens to have positive optical power and its object-side surface to be convex, the fourth lens to have negative optical power, the fifth lens to have a convex image-side surface, the sixth lens to have a concave object-side surface and a convex image-side surface respectively, and the eighth lens to have negative optical power and its image-side surface to be concave, and by constraining the positions of the first to the eighth spacer elements and the conditions 5.19≤L / ∑CP≤10.92 and 13.76≤R11 / R12×V6≤15.93, it can be seen that when the sixth lens is made of a high-dispersion material, it is easy to impose certain restrictions on the curvature of the two side surfaces of the sixth lens, thereby limiting the size design of the edge structure of the sixth lens, increasing the design difficulty of the lens structure arrangement, and blindly arranging the design will lead to unreasonable and unstable transitions of the spacer elements located before and after the sixth lens. During assembly, the sixth lens is prone to assembly deformation and stress concentration, affecting the assembly stability of the optical imaging device. Therefore, this application constrains 2.68≤(EP56+∑CP6) / CT6≤3.90, controlling the ratio of the distance between the fifth and sixth spacers on the optical axis to the sum of the axial thicknesses of all spacers between the sixth and seventh lenses to the center thickness of the sixth lens on the optical axis within a certain range. This facilitates the rational design of the edge structure dimensions of the sixth lens, balancing the edge thickness and center thickness of the sixth lens. Since the edge structure of the sixth lens is used to support the lens barrel, the fifth spacer, and the sixth spacer, it helps to ensure the rational arrangement of the sixth lens and the front and rear spacers in the lens barrel, thereby reducing the risk of deformation and stress concentration during assembly of the sixth lens and ensuring the assembly stability of the optical imaging device. Attached Figure Description

[0025] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0026] Figure 1 A dimensioned diagram of an optical imaging apparatus according to an alternative embodiment of the present invention is shown;

[0027] Figure 2 A schematic diagram of the structure of the optical imaging device according to Embodiment 1-1 of the present invention is shown;

[0028] Figure 3 A schematic diagram of the optical imaging device according to embodiments 1-2 of the present invention is shown;

[0029] Figure 4 The diagram shows the structural schematics of the optical imaging devices according to embodiments 1-3 of the present invention;

[0030] Figures 5 to 8 Figures respectively show the magnification chromatic aberration curve, the on-axis chromatic aberration curve, the astigmatism curve and the distortion curve of the optical imaging device of the embodiment one of the present application;

[0031] Figure 9 Figure shows a structural schematic diagram of the optical imaging device of the embodiment 2-1 of the present application;

[0032] Figure 10 Figure shows a structural schematic diagram of the optical imaging device of the embodiment 2-2 of the present application;

[0033] Figure 11 Figure shows a structural schematic diagram of the optical imaging device of the embodiment 2-3 of the present application;

[0034] Figures 12 to 15 Figures respectively show the magnification chromatic aberration curve, the on-axis chromatic aberration curve, the astigmatism curve and the distortion curve of the optical imaging device of the embodiment two of the present application;

[0035] Figure 16 Figure shows a structural schematic diagram of the optical imaging device of the embodiment 3-1 of the present application;

[0036] Figure 17 Figure shows a structural schematic diagram of the optical imaging device of the embodiment 3-2 of the present application;

[0037] Figure 18 Figure shows a structural schematic diagram of the optical imaging device of the embodiment 3-3 of the present application;

[0038] Figures 19 to 22 Figures respectively show the magnification chromatic aberration curve, the on-axis chromatic aberration curve, the astigmatism curve and the distortion curve of the optical imaging device of the embodiment three of the present application;

[0039] Figure 23 Figure shows the assembly local stress diagram when the optical imaging device of the scheme 1 of the present application satisfies 5.19≤L / ∑CP≤10.92, 13.76≤R11 / R12×V6≤15.93 and (EP56+∑CP6) / CT6=3.80;

[0040] Figure 24 Figure shows the assembly local stress diagram when the optical imaging device of the scheme 2 of the present application satisfies 5.19≤L / ∑CP≤10.92, 13.76≤R11 / R12×V6≤15.93 and (EP56+∑CP6) / CT6=2.90;

[0041] Figure 25A local stress diagram of the optical imaging device of Comparative Example 1 is shown when 5.19≤L / ∑CP≤10.92, 13.76≤R11 / R12×V6≤15.93, and (EP56+∑CP6) / CT6=4.83 are satisfied.

[0042] Figure 26 A local stress diagram of the optical imaging device of Comparative Example 2 is shown when 5.19≤L / ∑CP≤10.92, 13.76≤R11 / R12×V6≤15.93, and (EP56+∑CP6) / CT6=2.30 are satisfied.

[0043] Wherein, the above-mentioned drawings include the following reference signs:

[0044] P0, a lens barrel; E1, a first lens; S1, an object side surface of the first lens; S2, an image side surface of the first lens; E2, a second lens; S3, an object side surface of the second lens; S4, an image side surface of the second lens; E3, a third lens; S5, an object side surface of the third lens; S6, an image side surface of the third lens; E4, a fourth lens; S7, an object side surface of the fourth lens; S8, an image side surface of the fourth lens; E5, a fifth lens; S9, an object side surface of the fifth lens; S10, an image side surface of the fifth lens; E6, a sixth lens; S11, an object side surface of the sixth lens; S12, an image side surface of the sixth lens; E7, a seventh lens; S13, an object side surface of the seventh lens; S14, an image side surface of the seventh lens; E8, an eighth lens; S15, an object side surface of the eighth lens; S16, an image side surface of the eighth lens; P1, a first spacer element; P2, a second spacer element; P3, a third spacer element; P4, a fourth spacer element; P5, a fifth spacer element; P6, a sixth spacer element; P7, a seventh spacer element; P8, an eighth spacer element. DETAILED DESCRIPTION

[0045] It should be noted that the embodiments and features in the embodiments of the present application can be combined with each other without conflict. The present application will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0046] It should be noted that, unless otherwise specified, all technical and scientific terms used in the present application have the same meanings as commonly understood by those skilled in the art to which the present application belongs.

[0047] In the present application, unless otherwise specified, the orientation words such as "upper", "lower", "top", "bottom" are generally directed to the directions shown in the drawings, or are directed to the vertical, perpendicular or gravity directions of the components themselves; similarly, for the convenience of understanding and description, "inner" and "outer" refer to the inner and outer relative to the contour of the components themselves, but the above orientation words are not used to limit the present application.

[0048] It should be noted that in this specification, the terms "first," "second," "third," etc., are used only to distinguish one feature from another and do not imply any limitation on the features. Therefore, without departing from the teachings of this application, the first lens discussed below may also be referred to as the second lens or the third lens.

[0049] In the accompanying drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for ease of illustration. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are illustrated by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustrative purposes only and are not drawn strictly to scale.

[0050] In this paper, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the location of the convexity is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the location of the concaveness is not defined, it means that the lens surface is concave at least in the paraxial region. The surface shape in the paraxial region can be determined according to the judgment method commonly known in the art, using the R value (R refers to the radius of curvature of the paraxial region, usually the R value in the lens database of optical software) to determine concavity or convexity. For the object side, when the R value is positive, it is determined to be convex, and when the R value is negative, it is determined to be concave; for the image side, when the R value is positive, it is determined to be concave, and when the R value is negative, it is determined to be convex. In this application, the left side is the object side, and the right side is the image side.

[0051] To address the problem in existing eight-element optical imaging devices where the tail lens is made of a high-dispersion material, resulting in an unreasonable tail lens size and stress concentration and deformation during assembly, this invention provides an optical imaging device.

[0052] like Figures 1 to 24 As shown, in an optional embodiment of this application, the optical imaging device includes a lens barrel and a lens group and a spacer element group disposed in the lens barrel.

[0053] The lens group consists of eight lenses, which are arranged sequentially from the object side to the image side as follows: a first lens with positive optical power, a second lens with optical power, a third lens with optical power, a fourth lens with negative optical power, a fifth lens with optical power, a sixth lens with optical power, a seventh lens with optical power, and an eighth lens with negative optical power. The object side of the first lens is convex, the image side of the fifth lens is convex, the object side of the sixth lens is concave, the image side of the eighth lens is convex, and the image side of the eighth lens is concave. Each adjacent pair of lenses from the first to the eighth lens has an air gap on the optical axis of the optical imaging device.

[0054] The spacer element group includes a first spacer element disposed between the first lens and the second lens and abutting against an image-side surface portion of the first lens, a second spacer element disposed between the second lens and the third lens and abutting against an image-side surface portion of the second lens, a third spacer element disposed between the third lens and the fourth lens and abutting against an image-side surface portion of the third lens, a fourth spacer element disposed between the fourth lens and the fifth lens and abutting against an image-side surface portion of the fourth lens, a fifth spacer element disposed between the fifth lens and the sixth lens and abutting against an image-side surface portion of the fifth lens, a sixth spacer element disposed between the sixth lens and the seventh lens and abutting against an image-side surface portion of the sixth lens, a seventh spacer element disposed between the seventh lens and the eighth lens and abutting against an image-side surface portion of the seventh lens, and an eighth spacer element disposed on an image side of the eighth lens and abutting against an image-side surface portion of the eighth lens.

[0055] The maximum axial height L of the lens barrel and the sum ∑CP of the axial thicknesses of all the spacer elements of the optical imaging device satisfy: 5.19 ≤ L / ∑CP ≤ 10.92; the radius of curvature R11 of the object-side surface of the sixth lens, the radius of curvature R12 of the image-side surface of the sixth lens, and the Abbe number V6 of the sixth lens satisfy: 13.76 ≤ R11 / R12 × V6 ≤ 15.93; the interval distance EP56 on the optical axis from the image-side surface of the fifth spacer element to the object-side surface of the sixth spacer element, the sum ∑CP6 of the axial thicknesses of all the spacer elements between the sixth lens and the seventh lens, and the central thickness CT6 of the sixth lens on the optical axis satisfy: 2.68 ≤ (EP56 + ∑CP6) / CT6 ≤ 3.90.

[0056] The optical imaging device of the present application is composed of a lens barrel and eight lenses and a plurality of spacer elements arranged in the lens barrel. By reasonably arranging the first lens to have a positive focal length and the object side of the first lens to be convex, the fourth lens to have a negative focal length, the image side of the fifth lens to be convex, the object side and the image side of the sixth lens to be concave and convex respectively, the eighth lens to have a negative focal length and the image side of the eighth lens to be concave, and by restricting the positions of the first spacer element to the eighth spacer element and 5.19≤L / ∑CP≤10.92, 13.76≤R11 / R12×V6≤15.93, it can be seen that in the case of using a highly dispersive material for the sixth lens, the curvature of the two side surfaces of the sixth lens is limited to a certain extent, thereby limiting the size design of the edge structure of the sixth lens, and increasing the design difficulty of the structure arrangement of the lens. Blind arrangement design will lead to unreasonable and unstable transition of the spacer elements located before and after the sixth lens, and in the assembly process, the sixth lens is prone to assembly deformation and stress concentration, affecting the assembly stability of the optical imaging device. Therefore, by restricting 2.68≤(EP56+∑CP6) / CT6≤3.90, by controlling the ratio of the interval distance of the fifth spacer element to the sixth spacer element on the optical axis and the sum of the axial thicknesses of all the spacer elements located between the sixth lens and the seventh lens to the central thickness of the sixth lens on the optical axis within a certain range, it is beneficial to reasonably design the size of the edge structure of the sixth lens, balance the edge thickness and the central thickness of the sixth lens. Since the edge structure of the sixth lens is used to bear against the lens barrel, the fifth spacer element and the sixth spacer element, it is beneficial to ensure the reasonable arrangement of the sixth lens and the front and rear spacer elements in the lens barrel, to reduce the risk of deformation and stress concentration of the sixth lens during assembly, and to ensure the assembly stability of the optical imaging device.

[0057] It should be noted that the maximum axial height L of the lens barrel is the interval distance of the object side end surface of the lens barrel to the image side end surface of the lens barrel along the optical axis.

[0058] In addition, as shown in the following Table 1, Figures 23 to 26 under the premise that the optical imaging device satisfies 5.19≤L / ∑CP≤10.92, 13.76≤R11 / R12×V6≤15.93, for example, L / ∑CP=5.23, R11 / R12×V6=15.93, or L / ∑CP=5.19, R11 / R12×V6=13.76. Figure 23 shows the assembly local stress diagram of the optical imaging device of scheme 1 of the present application when (EP56+∑CP6) / CT6=3.80, Figure 24 shows the assembly local stress diagram of the optical imaging device of scheme 2 of the present application when (EP56+∑CP6) / CT6=2.90, Figure 25The assembly local stress diagram of the optical imaging device of Comparative Example 1 is shown when (EP56+∑CP6) / CT6=4.83 is satisfied, Figure 26 The assembly local stress diagram of the optical imaging device of Comparative Example 2 is shown when (EP56+∑CP6) / CT6=2.30 is satisfied.

[0059] From 23 to Figure 26 It can be seen that when the optical imaging device satisfies (EP56+∑CP6) / CT6=3.80, the maximum value of the stress generated by the sixth lens during the assembly process is 12.805 Mpa, the minimum value is 0.0010919 Mpa, the stress generated by the sixth lens is smaller, the deformation of the sixth lens during the assembly process is smaller, and the assembly stability is better. When the optical imaging device satisfies (EP56+∑CP6) / CT6=2.90, the maximum value of the stress generated by the sixth lens during the assembly process is 12.566 Mpa, the minimum value is 0.0019303 Mpa, the stress generated by the sixth lens is smaller, the deformation of the sixth lens during the assembly process is smaller, and the assembly stability is better. When the optical imaging device satisfies (EP56+∑CP6) / CT6=4.83, the maximum value of the stress generated by the sixth lens during the assembly process is 29.694 Mpa, the minimum value is 0.00052836 Mpa, the stress generated by the sixth lens is larger, which is easy to cause the deformation or even the fracture of the sixth lens, and affects the normal assembly of the optical imaging device. When the optical imaging device satisfies (EP56+∑CP6) / CT6=2.30, the maximum value of the stress generated by the sixth lens during the assembly process is 29.795 Mpa, the minimum value is 0.0037298 Mpa, the local stress of the sixth lens is increased, which is easy to cause the deformation of the sixth lens, and affects the normal assembly of the optical imaging device.

[0060] Therefore, when 5.19≤L / ∑CP≤10.92, 13.76≤R11 / R12×V6≤15.93, and (EP56+∑CP6) / CT6 is controlled in the range of 2.68 to 3.90 are satisfied, the stress generated by the sixth lens during the assembly process is smaller, the deformation of the sixth lens is smaller, and the assembly stability is best. Therefore, the present application restricts 5.19≤L / ∑CP≤10.92, 13.76≤R11 / R12×V6≤15.93, and 2.68≤(EP56+∑CP6) / CT6≤3.90. On the basis of satisfying the compact structure and the imaging requirement, it is beneficial to reasonably design the size of the edge structure of the sixth lens, balance the edge thickness and the center thickness of the sixth lens, and since the edge structure of the sixth lens is used for abutting against the lens barrel, the fifth spacer element and the sixth spacer element, it is beneficial to ensure the reasonable arrangement of the sixth lens and the front and rear spacer elements in the lens barrel, so as to reduce the risk of deformation and stress concentration of the sixth lens during the assembly, and further ensure the assembly stability of the optical imaging device.

[0061] Table 1

[0062] Scheme 1 of the present application Scheme 2 of the present application Comparative Example 1 Comparative Example 2 (EP56 + ∑CP6) / CT6 3.80 2.90 4.83 2.30

[0063] In one optional embodiment of the present application, the group of spacer elements consists of only the first to eighth spacer elements, and no auxiliary spacer element is provided. In this case, ∑CP is the sum of the axial thicknesses of the first to eighth spacer elements, and ∑CP6 is the axial thickness of the sixth spacer element.

[0064] In another optional embodiment of the present application, the group of spacer elements further includes one or two auxiliary spacer elements disposed between the sixth spacer element and the seventh lens, and the third auxiliary spacer element disposed between the third spacer element and the fourth lens. When one auxiliary spacer element is disposed between the sixth spacer element and the seventh lens and the third auxiliary spacer element is disposed between the third spacer element and the fourth lens, the auxiliary spacer element between the sixth spacer element and the seventh lens is the sixth auxiliary spacer element. In this case, ∑CP is the sum of the axial thicknesses of the first to eighth spacer elements, the third auxiliary spacer element, and the sixth auxiliary spacer element, and ∑CP6 is the sum of the axial thicknesses of the sixth spacer element and the sixth auxiliary spacer element.

[0065] In another optional embodiment of the present application, the difference between this embodiment and the previous optional embodiment is that a seventh auxiliary spacer element is further disposed between the seventh spacer element and the eighth lens. In this case, ∑CP is the sum of the axial thicknesses of the first to eighth spacer elements, the third auxiliary spacer element, the sixth auxiliary spacer element, and the seventh auxiliary spacer element.

[0066] In another optional embodiment of the present application, the group of spacer elements further includes two auxiliary spacer elements disposed between the sixth spacer element and the seventh lens, which are the sixth auxiliary spacer element and the sixth auxiliary spacer element, respectively, and the sixth auxiliary spacer element is located on the image side of the sixth auxiliary spacer element, and the third auxiliary spacer element disposed between the third spacer element and the fourth lens. In this case, ∑CP is the sum of the axial thicknesses of the first to eighth spacer elements, the third auxiliary spacer element, the sixth auxiliary spacer element, and the sixth auxiliary spacer element, and ∑CP6 is the sum of the axial thicknesses of the sixth spacer element, the sixth auxiliary spacer element, and the sixth auxiliary spacer element.

[0067] In the embodiment, the object side surface of the fourth lens is convex, the inner diameter d3m of the image side surface of the third spacer element, the outer diameter D3m of the image side surface of the third spacer element and the curvature radius R7 of the object side surface of the fourth lens satisfy: 0.90≤(d3m+D3m) / R7≤1.63. The arrangement can control the ratio of the sum of the outer diameter and the inner diameter of the image side surface of the third spacer element to the curvature radius of the object side surface of the fourth lens, optimize the performance of the system, ensure that the third spacer element is not too close or far away from the fourth lens, and ensure that the third spacer element can effectively intercept unnecessary stray light, thereby avoiding aberration, light blocking or other optical problems.

[0068] In the embodiment, the inner diameter d8s of the object side surface of the eighth spacer element, the curvature radius R15 of the object side surface of the eighth lens and the curvature radius R16 of the image side surface of the eighth lens satisfy: -1.90≤d8s / (R15+R16)≤1.25. By limiting the ratio of the inner diameter of the object side surface of the eighth spacer element to the sum of the curvature radii of the object side surface and the image side surface of the eighth lens, the size interference between the eighth spacer element and the eighth lens can be avoided, the imaging light can smoothly pass through the eighth spacer element and the eighth lens without being blocked or deflected, and the stability and reliability of the system are improved.

[0069] In the embodiment, the interval distance EP23 on the optical axis from the image side surface of the second spacer element to the object side surface of the third spacer element and the interval distance EP34 on the optical axis from the image side surface of the third spacer element to the object side surface of the fourth spacer element satisfy: 0.64≤EP23 / EP34≤1.42. By controlling the ratio of the interval distance on the optical axis from the image side surface of the second spacer element to the object side surface of the third spacer element to the interval distance on the optical axis from the image side surface of the third spacer element to the object side surface of the fourth spacer element, the thickness distribution of the edge structure of the third lens and the fourth lens is controlled, and the forming stability of the third lens and the fourth lens is ensured.

[0070] In the embodiment, the outer diameter D7m of the image side surface of the seventh spacer element, the inner diameter d8s of the object side surface of the eighth spacer element and the center thickness CT8 of the eighth lens on the optical axis satisfy: 0.12≤(D7m-d8s) / CT8≤1.34. By limiting the difference between the outer diameter of the image side surface of the seventh spacer element and the inner diameter of the object side surface of the eighth spacer element, it is ensured that there is enough imaging light to pass stably, and it is ensured that the seventh spacer element and the eighth spacer element can intercept stray light, effectively avoiding unnecessary stray light from reaching the imaging surface, which helps to reduce aberration and distortion in the system and improve imaging quality; at the same time, the center thickness of the eighth lens is controlled relative to the size difference of the seventh spacer element and the eighth spacer element, which to some extent maintains the compactness of the optical imaging device, avoids assembly difficulties or performance problems caused by excessive thickness of the lens, and improves the overall performance.

[0071] In the embodiment, the maximum axial height L of the lens barrel, the sum ∑AT of the air gaps of any two adjacent lenses among the first lens to the eighth lens on the optical axis, and the air interval T34 of the third lens and the fourth lens on the optical axis satisfy: 8.44≤(L-∑AT) / T34≤10.43. ∑AT is the sum of the air gaps of any two adjacent lenses among the first lens to the eighth lens on the optical axis. By controlling the expression, the maximum axial height of the lens barrel and the air gap between adjacent lenses are constrained, which ensures the compactness of the spatial size of the optical imaging device, is conducive to the compression of the volume and the light weight of the optical imaging device; at the same time, the air interval of the third lens and the fourth lens on the optical axis is controlled, which plays a role in reducing chromatic aberration, suppressing reflection and scattering of internal light in the optical imaging device, and is conducive to improving the imaging quality and overall performance of the optical imaging device.

[0072] In the embodiment, the object side surface of the seventh lens is a convex surface, the outer diameter D6m of the image side surface of the sixth spacer element, the inner diameter d6m of the image side surface of the sixth spacer element, and the radius of curvature R13 of the object side surface of the seventh lens satisfy: 0.17≤(D6m-d6m) / R13≤1.61. By controlling the difference between the outer diameter and the inner diameter of the sixth spacer element, it is ensured that the sixth spacer element can effectively block unnecessary stray light, and at the same time, the outer diameter of the sixth spacer element is controlled, which is conducive to ensuring the stability and uniformity of the wall thickness of the lens barrel; on this premise, the radius of curvature of the object side surface of the seventh lens is further controlled, which ensures that the seventh lens can effectively receive and cooperate with the front and rear lenses, reduces the aberration of the overall system, and improves the resolution.

[0073] In the embodiment, the outer diameter D0s of the object side end surface of the lens barrel, the inner diameter d1s of the object side surface of the first spacer element, and the center thickness CT1 of the first lens on the optical axis satisfy: 6.78≤(D0s-d1s) / CT1≤7.95. By limiting the difference between the outer diameter of the object side end surface of the lens barrel and the inner diameter of the first spacer element, it can be ensured that the optical imaging device has sufficient light flux and that the first spacer element can intercept stray light, avoid the passage of excess stray light, and improve the imaging quality; at the same time, the center thickness of the first lens is limited, which is conducive to controlling the overall shape of the central effective diameter part of the first lens, and ensures the processing and forming stability of the first lens.

[0074] In the embodiment, the sixth lens has negative refractive power, and the effective focal length f6 of the sixth lens, the interval distance EP56 on the optical axis from the image side surface of the fifth spacer element to the object side surface of the sixth spacer element, and the central thickness CT6 of the sixth lens on the optical axis satisfy: 4.89≤|f6| / (EP56+CT6)≤8.06. By controlling the sixth lens to have negative refractive power and the size of the effective focal length f6, it can be ensured that the sixth lens can effectively receive the imaging light passing through the fifth lens and effectively pass to the seventh lens, thereby indirectly ensuring the magnification, the field of view angle, and the depth of field of the optical imaging device; and the control of the interval distance on the optical axis from the image side surface of the fifth spacer element to the object side surface of the sixth spacer element and the central thickness of the sixth lens on the optical axis ensures the rationality of the size of the sixth lens, and further ensures the rationality and compactness of the overall layout of the optical imaging device, thereby being conducive to ensuring the stability of assembly and the stability of structure transition.

[0075] In the embodiment, the second lens has positive refractive power, and the effective focal length f2 of the second lens, the refractive index N2 of the second lens, and the inner diameter d2m of the image side surface of the second spacer element satisfy: 2.88≤f2×N2 / d2m≤4.48. By controlling the effective focal length of the second lens and the refractive index of the second lens, it can be ensured that there is enough light passing through the second lens and more efficient transmission to the subsequent lens, and further by controlling the inner diameter of the second spacer element, unnecessary stray light is intercepted, and the overall imaging quality is improved.

[0076] In the embodiment, the distance from the object side surface of the first spacer element to the object side surface of the first spacer element of the lens barrel and the sum ∑EP of the interval distances on the optical axis of the first spacer element to the adjacent two spacer elements in the eighth spacer element satisfy: 10.49≤∑EP / EP12≤13.27. By limiting the sum of the interval distances of all adjacent spacer elements, the internal space of the optical imaging device is optimized under the premise of ensuring the rationality of the size of the optical imaging device; and further controlling the distance from the image side surface of the first spacer element to the object side surface of the second spacer element ensures the stability of the first spacer element and the second spacer element as the arrangement basis of the entire system, and improves the stability of the overall system imaging quality.

[0077] Here, it needs to be explained that ∑EP is the sum of the distance from the object side surface of the lens barrel to the object side surface of the first spacer element, the interval distance on the optical axis from the image side surface of the first spacer element to the object side surface of the second spacer element, the interval distance on the optical axis from the image side surface of the second spacer element to the object side surface of the third spacer element, the interval distance on the optical axis from the image side surface of the third spacer element to the object side surface of the fourth spacer element, the interval distance on the optical axis from the image side surface of the fourth spacer element to the object side surface of the fifth spacer element, the interval distance on the optical axis from the image side surface of the fifth spacer element to the object side surface of the sixth spacer element, the interval distance on the optical axis from the image side surface of the sixth spacer element to the object side surface of the seventh spacer element, and the interval distance on the optical axis from the image side surface of the seventh spacer element to the object side surface of the eighth spacer element.

[0078] In the present embodiment, the image side surface of the seventh lens is a concave surface, and the radius of curvature R14 of the image side surface of the seventh lens and the inner diameter d7s of the object side surface of the seventh spacer element satisfy: 0.93≤R14 / d7s≤1.71. By controlling the conditional expression, the radius of curvature of the seventh lens and the inner diameter of the seventh spacer element are limited, the propagation path of light before and after the seventh lens can be adjusted, and the seventh spacer element can intercept unnecessary stray light, thereby optimizing the imaging quality.

[0079] In the present embodiment, the radius of curvature R10 of the image side surface of the fifth lens, the outer diameter D5m of the image side surface of the fifth spacer element, and the refractive index N5 of the fifth lens satisfy: -2.47≤R10×N5 / D5m≤-1.68. By the above expression, the refractive index of the fifth lens and the radius of curvature of the image side surface of the fifth lens are limited, the bending degree of the fifth lens is controlled under the premise of meeting the optical imaging requirements, the fifth lens has good formability, the outer diameter of the image side surface of the fifth spacer element is limited, the contact area of the fifth lens and the fifth spacer element can be controlled, and the assembly stability of the fifth lens is improved.

[0080] In the present embodiment, the interval distance EP78 on the optical axis from the image side surface of the seventh spacer element to the object side surface of the eighth spacer element, the axial thickness CP8 of the eighth spacer element, and the central thickness CT8 of the eighth lens on the optical axis satisfy: 2.04≤(EP78+CP8) / CT8≤2.71. By controlling EP78 and CP8, the stability of the seventh spacer element, the eighth lens, and the eighth spacer element is ensured, the rationality of the size transition of the lens barrel is ensured, and the central thickness of the eighth lens on the optical axis is controlled, the thickness ratio of the eighth lens is controlled, and the forming process capability of the eighth lens is ensured.

[0081] In the embodiment, the third lens has negative refractive power, the fifth lens has positive refractive power, and the seventh lens has positive refractive power; the image side surface of the first lens is a concave surface, the object side surface of the second lens is a convex surface, the object side surface of the third lens is a convex surface, the image side surface of the third lens is a concave surface, the image side surface of the fourth lens is a concave surface, and the object side surface of the fifth lens is a convex surface. By reasonably constraining the refractive power and surface shape of each lens, the light path can be controlled to ensure smooth transition of light, and the aberration and distortion can be optimized to ensure imaging quality.

[0082] Optionally, the optical imaging device in the embodiment of the present application can be simulated by software and / or tools such as ZEMAX, CODEV, etc. In the process of simulation by software and / or tools such as the above, the surface shape of each lens can be simulated according to the surface shape provided by the software and / or tools used, and appropriately adjusted.

[0083] In addition, in another optional embodiment of the present application, an optical imaging device is also provided, which comprises a lens barrel, a lens group and a spacer element group arranged in the lens barrel.

[0084] The lens group is composed of eight lenses, which are, in order from the object side to the image side, a first lens having positive refractive power, a second lens having refractive power, a third lens having refractive power, a fourth lens having negative refractive power, a fifth lens having refractive power, a sixth lens having refractive power, a seventh lens having refractive power, and an eighth lens having negative refractive power; the object side surface of the first lens is a convex surface, the image side surface of the fifth lens is a convex surface, the object side surface of the sixth lens is a concave surface, the image side surface of the sixth lens is a convex surface, and the image side surface of the eighth lens is a concave surface; and each of the adjacent two lenses among the first to eighth lenses has an air gap on the optical axis of the optical imaging device.

[0085] The spacer element group comprises the first to eighth spacer elements in the above embodiment.

[0086] The maximum axial height L of the lens barrel and the effective focal length f of the optical imaging device satisfy 1.40≤L / f≤1.53; the radius of curvature R11 of the object side surface of the sixth lens, the radius of curvature R12 of the image side surface of the sixth lens, and the Abbe number V6 of the sixth lens satisfy 13.76≤R11 / R12×V6≤15.93; the sixth lens has negative refractive power, the effective focal length f6 of the sixth lens, the interval distance EP56 on the optical axis from the image side surface of the fifth spacer element to the object side surface of the sixth spacer element, and the central thickness CT6 of the sixth lens on the optical axis satisfy 4.89≤|f6| / (EP56+CT6)≤8.06.

[0087] The optical imaging device of the present application is composed of a lens barrel and eight lenses and a plurality of spacer elements arranged in the lens barrel. By reasonably arranging the first lens to have a positive focal length and the object side thereof to be a convex surface, the fourth lens to have a negative focal length, the image side of the fifth lens to be a convex surface, the object side and the image side of the sixth lens to be a concave surface and a convex surface respectively, the eighth lens to have a negative focal length and the image side thereof to be a concave surface, and restricting the positions of the first spacer element to the eighth spacer element and 1.40≤L / f≤1.53 and 13.76≤R11 / R12×V6≤15.93, it can be seen that in the case of using a highly dispersive material for the sixth lens, the compression of the overall size limits the design of the size of the sixth lens, increasing the difficulty of structural arrangement and design of the sixth lens. Therefore, by restricting 4.89≤|f6| / (EP56+CT6)≤8.06, by controlling the sixth lens to have a negative focal length and the size of the effective focal length f6, the sixth lens can effectively receive the imaging light passing through the fifth lens and effectively transmit to the seventh lens, thereby indirectly ensuring the magnification, the field of view angle and the depth of field of the optical imaging device; and the control of the interval distance on the optical axis from the image side of the fifth spacer element to the object side of the sixth spacer element and the central thickness of the sixth lens on the optical axis ensures the rationality of the size of the tail-end sixth lens, thereby ensuring the rational arrangement of the sixth lens in the lens barrel, ensuring the stability of the structure transition and the smoothness of the light transmission.

[0088] Of course, other parameter formulas in the above embodiments can also be included in the present embodiment, which will not be described one by one here.

[0089] In addition, in another optional embodiment of the present application, an optical imaging device is also provided, which comprises a lens barrel and a lens group and a spacer element group arranged in the lens barrel, the lens group is composed of eight lenses, and the eight lenses are sequentially arranged from the object side to the image side as a first lens having a positive focal length, a second lens having a focal length, a third lens having a focal length, a fourth lens having a negative focal length, a fifth lens having a focal length, a sixth lens having a focal length, a seventh lens having a focal length and an eighth lens having a negative focal length; the object side of the first lens is a convex surface, the image side of the fifth lens is a convex surface, the object side of the sixth lens is a concave surface, the image side of the sixth lens is a convex surface, and the image side of the eighth lens is a concave surface; the adjacent two lenses in the first lens to the eighth lens have an air gap on the optical axis of the optical imaging device.

[0090] The spacer element group comprises the first spacer element to the eighth spacer element in the above embodiments.

[0091] The maximum axial height L of the lens barrel and the effective focal length f of the optical imaging device satisfy: 1.40≤L / f≤1.53; the radius of curvature R11 of the object side surface of the sixth lens, the radius of curvature R12 of the image side surface of the sixth lens, and the Abbe number V6 of the sixth lens satisfy: 13.76≤R11 / R12×V6≤15.93; the interval distance EP56 of the image side surface of the fifth spacer element to the object side surface of the sixth spacer element on the optical axis, the central thickness CT6 of the sixth lens on the optical axis, and the radius of curvature R11 of the object side surface of the sixth lens satisfy: -9.58≤EP56 / CT6×R11≤-5.86.

[0092] The optical imaging device of the present application is composed of a lens barrel and eight lenses and a plurality of spacer elements arranged in the lens barrel. By reasonably arranging that the first lens has positive focal power and its object side surface is convex, the fourth lens has negative focal power, the image side surface of the fifth lens is convex, the object side surface and the image side surface of the sixth lens are concave and convex respectively, the eighth lens has negative focal power and its image side surface is concave, and by reasonably arranging the positions of the first spacer element to the eighth spacer element and 1.40≤L / f≤1.53 and 13.76≤R11 / R12×V6≤15.93, it can be seen that in the case of using a highly dispersive material for the sixth lens, the compression of the overall size limits the design of the size of the sixth lens, increasing the difficulty of structural arrangement and design of the sixth lens. Therefore, by reasonably arranging -9.58≤EP56 / CT6×R11≤-5.86, the shape and size of the sixth lens are constrained, the rationality of the size of the sixth lens is ensured, and then the sixth lens can effectively receive the imaging light passing through the fifth lens and effectively transmit to the seventh lens, ensuring the smoothness of light transmission, ensuring the rationality and compactness of the overall layout of the optical imaging device.

[0093] Of course, the present embodiment can also include other parameter formulas in the above embodiments, which will not be described one by one here.

[0094] Optionally, the optical imaging device can further include a protective glass for protecting the photosensitive element located on the imaging surface.

[0095] The optical imaging device in the present application can use multiple lenses, for example, eight lenses as described above. In the present application, at least one of the mirror surfaces of each lens is a non-spherical mirror surface. The characteristic of the aspherical lens is that the curvature is continuously changed from the center of the lens to the periphery of the lens. Unlike the spherical lens which has a constant curvature from the center of the lens to the periphery of the lens, the aspherical lens has better curvature radius characteristics and has the advantages of improving distortion aberration and improving astigmatism aberration. After using the aspherical lens, the aberration that occurs during imaging can be eliminated as much as possible, thereby improving the imaging quality.

[0096] However, those skilled in the art should understand that the number of lenses constituting the optical imaging device can be changed without departing from the technical solutions claimed in the present application, to obtain the various results and advantages described in the present specification. For example, although eight lenses are described as an example in the embodiments, the optical imaging device is not limited to including eight lenses. If necessary, the optical imaging device can also include other numbers of lenses.

[0097] Figure 1 The size annotation diagram of one optical imaging device of the present application is shown, Figure 1 The parameters d1s, d2m, d3m, D3m, D0s, D5m, d6m, D6m, d7s, D7m, d8s, EP12, EP23, EP34, EP56, EP78, L, CP8 and ∑CP6 are marked in the figure to clearly and intuitively understand the meaning of the parameters. In order to facilitate the description of the optical imaging device and the surface shape of the specific lens, these parameters are no longer embodied in the figure when the specific embodiments are described below.

[0098] The specific surface shape and parameters of the optical imaging device applicable to the above embodiments are further described below with reference to the accompanying drawings.

[0099] It should be noted that there are three examples of embodiment 1-1, embodiment 1-2 and embodiment 1-3 in the following embodiment one, there are three examples of embodiment 2-1, embodiment 2-2 and embodiment 2-3 in the following embodiment two, and there are three examples of embodiment 3-1, embodiment 3-2 and embodiment 3-3 in the following embodiment three. The curvature radius, central thickness and other parameters of the first lens to the eighth lens of the optical imaging device in the three examples in the same embodiment are the same, but the thickness, inner diameter and outer diameter of the lens barrel, the first spacing element to the eighth spacing element are different. Or, the main structure for imaging is the same, and the auxiliary structure for imaging is different.

[0100] It should be noted that any one of the following embodiments one to three is applicable to all embodiments of the present application.

[0101] Embodiment one

[0102] As Figures 2 to 8 shown, the optical imaging device of embodiment one is described. Figure 2 The structural schematic diagram of the optical imaging device of embodiment 1-1 is shown, Figure 3 The structural schematic diagram of the optical imaging device of embodiment 1-2 is shown, Figure 4 The structural schematic diagram of the optical imaging device of embodiment 1-3 is shown.

[0103] AsFigures 2 to 4 As shown, the optical imaging device includes a lens barrel P0 and a first lens E1, a first spacer P1, a second lens E2, a second spacer P2, a third lens E3, a third spacer P3, a fourth lens E4, a fourth spacer P4, a fifth lens E5, a fifth spacer P5, a sixth lens E6, a sixth spacer P6, a seventh lens E7, a seventh spacer P7, an eighth lens E8, and an eighth spacer P8 arranged sequentially along the optical axis from the object side to the image side in the lens barrel P0.

[0104] like Figure 2 The diagram shows a schematic representation of the optical imaging device in Embodiment 1-1. In this example, the object-side and image-side of the first spacer element P1 abut against the image-side S2 of the first lens and the object-side S3 of the second lens, respectively. The object-side and image-side of the second spacer element P2 abut against the image-side S4 of the second lens and the object-side S5 of the third lens, respectively. The object-side and image-side of the third spacer element P3 abut against the image-side S6 of the third lens and the object-side S7 of the fourth lens, respectively. The object-side and image-side of the fourth spacer element P4 abut against the image-side S8 of the fourth lens and the object-side S9 of the fifth lens, respectively. The object-side and image-side of the fifth spacer element P5 abut against the image-side S10 of the fifth lens and the object-side S11 of the sixth lens, respectively. The object-side and image-side of the sixth spacer element P6 abut against the image-side S12 of the sixth lens and the object-side S13 of the seventh lens, respectively. The object-side and image-side surfaces of the seventh spacer element P7 abut against the image-side surface S14 of the seventh lens and the object-side surface S15 of the eighth lens, respectively. The object-side surface of the eighth spacer element P8 abuts against the image-side surface S16 of the eighth lens.

[0105] like Figure 3 The diagram shows a schematic of the optical imaging device according to Embodiment 1-2. The difference between this example and Embodiment 1-1 is that a third auxiliary spacer element P3b is also provided on the image side of the third spacer element P3, a sixth auxiliary spacer element P6b is also provided on the image side of the sixth spacer element P6, and a seventh auxiliary spacer element P7b is also provided on the image side of the seventh spacer element P7. In this case, the object side and image side of the third auxiliary spacer element P3b abut against the image side of the third spacer element P3 and the object side S7 portion of the fourth lens, respectively. The object side and image side of the sixth auxiliary spacer element P6b abut against the image side of the sixth spacer element P6 and the object side S13 portion of the seventh lens, respectively. The object side and image side of the seventh auxiliary spacer element P7b abut against the image side of the seventh spacer element P7 and the object side S15 portion of the eighth lens, respectively. The abutment and contact methods of the remaining spacer elements are the same as in Embodiment 1-1, and can be referred to the relevant description in Embodiment 1-1, which will not be repeated here.

[0106] like Figure 4Fig. 1 shows a structural schematic diagram of the optical imaging device of Example 1-1. In this example, the first auxiliary spacing element P1a is arranged on the image side of the first lens E1, and the second auxiliary spacing element P2a is arranged on the image side of the second lens E2. The rest of the spacing elements are arranged in the same way as in Example 1-1, and the relevant description can be referred to in Example 1-1, which will not be repeated here.

[0107] In summary, the structural parameters of the optical imaging device of Example 1-1, Example 1-2, and Example 1-3 are shown in Table 2 (unit: mm).

[0108] Table 2

[0109]

[0110]

[0111] In Example 1, the object side S1 of the first lens is a convex surface, and the image side S2 of the first lens is a concave surface. The object side S3 of the second lens is a convex surface, and the image side S4 of the second lens is a convex surface. The object side S5 of the third lens is a convex surface, and the image side S6 of the third lens is a concave surface. The object side S7 of the fourth lens is a convex surface, and the image side S8 of the fourth lens is a concave surface. The object side S9 of the fifth lens is a convex surface, and the image side S10 of the fifth lens is a convex surface. The object side S11 of the sixth lens is a concave surface, and the image side S12 of the sixth lens is a convex surface. The object side S13 of the seventh lens is a convex surface, and the image side S14 of the seventh lens is a concave surface. The object side S15 of the eighth lens is a convex surface, and the image side S16 of the eighth lens is a concave surface.

[0112] In Example 1, the effective focal length f of the optical imaging device is 5.39 mm, the effective focal length f1 of the first lens is 24.10 mm, the effective focal length f2 of the second lens is 5.67 mm, the effective focal length f3 of the third lens is -8.37 mm, the effective focal length f4 of the fourth lens is -21.75 mm, the effective focal length f5 of the fifth lens is 8.01 mm, the effective focal length f6 of the sixth lens is -9.02 mm, the effective focal length f7 of the seventh lens is 4.84 mm, and the effective focal length f8 of the eighth lens is -4.77 mm.

[0113] Table 3 shows the basic structural parameter table of the optical imaging device of Example 1, wherein the units of the curvature radius and the thickness / distance are millimeters (mm). In the following table, OBJ (not shown in the figure) is the object distance. STO (not shown in the figure) is the stop, which is located on the object side of the first lens E1. S17 and S18 (not shown in the figure) can be the object side and image side of the filter or the object side and image side of the protective glass. S19 (not shown in the figure) is the imaging surface.

[0114] Table 3

[0115]

[0116]

[0117] In embodiment one, the object side and image side of the first lens E1 to the eighth lens E8 are aspherical surfaces, and the surface type of each aspherical surface can be defined by, but not limited to, the following aspherical surface formula:

[0118]

[0119] wherein x is the sag of the aspherical surface at a position along the optical axis with a height of h, c is the paraxial curvature of the aspherical surface, c = 1 / R, i.e., the paraxial curvature c is the inverse of the curvature radius R in Table 3 above, k is the conic coefficient, and Ai is the correction coefficient of the i-th order of the aspherical surface. Table 4 below provides the high-order term coefficients A4, A6, A8, A10, A12, A14, A16, A18, and A20 that can be used for the aspherical surfaces S1-S16 in embodiment one.

[0120] Table 4

[0121]

[0122]

[0123] Figure 5 The lateral chromatic aberration curve of the optical imaging device of embodiment one is shown, which represents the deviation of light rays of different wavelengths after passing through the imaging lens. Figure 6 The on-axis chromatic aberration curve of the optical imaging device of embodiment one is shown, which represents the deviation of the converging focus points of light rays of different wavelengths after passing through the imaging lens. Figure 7 The astigmatism curve of the optical imaging device of embodiment one is shown, which represents the meridional image surface curvature and sagittal image surface curvature. Figure 8 The distortion curve of the optical imaging device of embodiment one is shown, which represents the distortion size values corresponding to different image heights.

[0124] According to Figures 5 to 8 It can be seen that the optical imaging device given in embodiment one can achieve good imaging quality.

[0125] Embodiment two

[0126] As Figures 9 to 15 shown, the optical imaging device of embodiment two is described. Figure 9 The structural schematic diagram of the optical imaging device of embodiment 2-1 is shown, Figure 10 The structural schematic diagram of the optical imaging device of embodiment 2-2 is shown, Figure 11 The structural schematic diagram of the optical imaging device of embodiment 2-3 is shown.

[0127] As shown in Figures 9 to 11 the optical imaging device includes a lens barrel P0 and, in order from the object side to the image side along the optical axis, 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 arranged in the lens barrel P0.

[0128] As shown in Figure 9 , it is a structural schematic diagram of the optical imaging device of Example 2-1. In this example, the object side and the image side of the first spacer element P1 are partially in contact with the image side S2 of the first lens and the object side S3 of the second lens respectively. The object side and the image side of the second spacer element P2 are partially in contact with the image side S4 of the second lens and the object side S5 of the third lens respectively. The object side and the image side of the third spacer element P3 are partially in contact with the image side S6 of the third lens and the object side S7 of the fourth lens respectively. The object side and the image side of the fourth spacer element P4 are partially in contact with the image side S8 of the fourth lens and the object side S9 of the fifth lens respectively. The object side and the image side of the fifth spacer element P5 are partially in contact with the image side S10 of the fifth lens and the object side S11 of the sixth lens respectively. The object side and the image side of the sixth spacer element P6 are partially in contact with the image side S12 of the sixth lens and the object side S13 of the seventh lens respectively. The object side and the image side of the seventh spacer element P7 are partially in contact with the image side S14 of the seventh lens and the object side S15 of the eighth lens respectively. The object side of the eighth spacer element P8 is partially in contact with the image side S16 of the eighth lens.

[0129] As shown in Figure 10 , it is a structural schematic diagram of the optical imaging device of Example 2-2. The difference between this example and Example 2-1 is that the image side of the third spacer element P3 is further provided with a third auxiliary spacer element P3b, and the image side of the sixth spacer element P6 is further sequentially provided with a sixth auxiliary spacer element P6b and a sixth auxiliary spacer element P6c. At this time, the object side and the image side of the third auxiliary spacer element P3b are partially in contact with the image side of the third spacer element P3 and the object side S7 of the fourth lens respectively. The object side and the image side of the sixth auxiliary spacer element P6b are partially in contact with the image side of the sixth spacer element P6 and the object side of the sixth auxiliary spacer element P6c, and the image side of the sixth auxiliary spacer element P6c is partially in contact with the object side S13 of the seventh lens. The contact and abutment modes of the remaining spacer elements are the same as those of Example 2-1, and reference can be made to the related description in Example 2-1, which will not be described here.

[0130] As shown in Figure 11Fig. 2-3 shows a structural schematic diagram of the optical imaging device of Example 2-3. The difference between this example and Example 2-2 is that the sixth auxiliary spacing element P6c is not provided, and the abutting modes of the remaining spacing elements are the same as those of Example 2-2. For details, please refer to the relevant description in Example 2-2, which will not be repeated here.

[0131] In summary, the structural parameters of the optical imaging device of Example 2 in Examples 2-1, 2-2 and 2-3 are shown in Table 5 (unit: mm).

[0132] Table 5

[0133]

[0134]

[0135] In Example 2, the object side S1 of the first lens is convex, and the image side S2 of the first lens is concave. The object side S3 of the second lens is convex, and the image side S4 of the second lens is concave. The object side S5 of the third lens is convex, and the image side S6 of the third lens is concave. The object side S7 of the fourth lens is convex, and the image side S8 of the fourth lens is concave. The object side S9 of the fifth lens is convex, and the image side S10 of the fifth lens is convex. The object side S11 of the sixth lens is concave, and the image side S12 of the sixth lens is convex. The object side S13 of the seventh lens is convex, and the image side S14 of the seventh lens is concave. The object side S15 of the eighth lens is concave, and the image side S16 of the eighth lens is concave.

[0136] In Example 2, the effective focal length f of the optical imaging device is 5.37 mm, the effective focal length f1 of the first lens is 16.93 mm, the effective focal length f2 of the second lens is 7.13 mm, the effective focal length f3 of the third lens is -8.76 mm, the effective focal length f4 of the fourth lens is -41.19 mm, the effective focal length f5 of the fifth lens is 7.22 mm, the effective focal length f6 of the sixth lens is -8.88 mm, the effective focal length f7 of the seventh lens is 5.21 mm, and the effective focal length f8 of the eighth lens is -4.63 mm.

[0137] Table 6 shows the basic structural parameters of the optical imaging device of Example 2, wherein the units of the curvature radius and the thickness / distance are millimeters (mm). In the following table, OBJ (not shown in the figure) is the object distance. STO (not shown in the figure) is the stop, which is located on the object side of the first lens E1. S17 and S18 (not shown in the figure) can be the object side and image side of the filter or the object side and image side of the protective glass. S19 (not shown in the figure) is the imaging surface.

[0138] Table 6

[0139]

[0140] The following Table 7 shows the high-order term coefficients A4, A6, A8, A10, A12, A14, A16, A18 and A20 of each aspherical mirror S1-S16 used in Example Two. The surface shape of each aspherical lens is defined according to the formula (1) in Example One.

[0141] Table 7

[0142]

[0143] Figure 12 The lateral chromatic aberration curve of the optical imaging device of Example Two is shown, which represents the deviation of light rays of different image heights after passing through the optical imaging device. Figure 13 The on-axis chromatic aberration curve of the optical imaging device of Example Two is shown, which represents the deviation of the converging focus points of light rays of different wavelengths after passing through the imaging lens. Figure 14 The astigmatism curve of the optical imaging device of Example Two is shown, which represents the meridional image surface curvature and sagittal image surface curvature. Figure 15 The distortion curve of the optical imaging device of Example Two is shown, which represents the distortion size values corresponding to different image heights.

[0144] According to Figures 12 to 15 It can be seen that the optical imaging device given in Example Two can achieve good imaging quality.

[0145] Example Three

[0146] As Figures 16 to 22 shown, the optical imaging device of Example Three is described. Figure 16 A structural schematic diagram of the optical imaging device of Example 3-1 is shown, Figure 17 A structural schematic diagram of the optical imaging device of Example 3-2 is shown, Figure 18 A structural schematic diagram of the optical imaging device of Example 3-3 is shown.

[0147] As Figures 16 to 18 shown, the optical imaging device includes a lens barrel P0 and, arranged in the lens barrel P0 in order from the object side to the image side along the optical axis, 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.

[0148] As Figure 16As shown in FIG. 3-1, it is a structural schematic diagram of the optical imaging device of Example 3-1. In this example, the object side and image side of the first spacer element P1 are partially in abutment with the image side S2 of the first lens and the object side S3 of the second lens, respectively. The object side and image side of the second spacer element P2 are partially in abutment with the image side S4 of the second lens and the object side S5 of the third lens, respectively. The object side and image side of the third spacer element P3 are partially in abutment with the image side S6 of the third lens and the object side S7 of the fourth lens, respectively. The object side and image side of the fourth spacer element P4 are partially in abutment with the image side S8 of the fourth lens and the object side S9 of the fifth lens, respectively. The object side and image side of the fifth spacer element P5 are partially in abutment with the image side S10 of the fifth lens and the object side S11 of the sixth lens, respectively. The object side and image side of the sixth spacer element P6 are partially in abutment with the image side S12 of the sixth lens and the object side S13 of the seventh lens, respectively. The object side and image side of the seventh spacer element P7 are partially in abutment with the image side S14 of the seventh lens and the object side S15 of the eighth lens, respectively. The object side of the eighth spacer element P8 is partially in abutment with the image side S16 of the eighth lens.

[0149] As shown in FIG. 3-2, it is a structural schematic diagram of the optical imaging device of Example 3-2. The difference between this example and Example 3-1 is that the image side of the third spacer element P3 is further provided with a third auxiliary spacer element P3b, and the image side of the sixth spacer element P6 is further sequentially provided with a sixth auxiliary spacer element P6b and a sixth auxiliary spacer element P6c. At this time, the object side and image side of the third auxiliary spacer element P3b are partially in abutment with the image side of the third spacer element P3 and the object side S7 of the fourth lens, respectively. The object side and image side of the sixth auxiliary spacer element P6b are partially in abutment with the image side of the sixth spacer element P6 and the object side of the sixth auxiliary spacer element P6c, and the image side of the sixth auxiliary spacer element P6c is partially in abutment with the object side S13 of the seventh lens. The abutment modes of the remaining spacer elements are the same as those of Example 3-1, and the relevant descriptions in Example 3-1 can be referred to, which will not be described here. Figure 17 As shown in FIG. 3-3, it is a structural schematic diagram of the optical imaging device of Example 3-3. The difference between this example and Example 3-2 is that the sixth auxiliary spacer element P6c is not provided, and the abutment modes of the remaining spacer elements are the same as those of Example 3-2, and the relevant descriptions in Example 3-2 can be referred to, which will not be described here.

[0150] Figure 18 As shown in FIG. 3-3, it is a structural schematic diagram of the optical imaging device of Example 3-3. The difference between this example and Example 3-2 is that the sixth auxiliary spacer element P6c is not provided, and the abutment modes of the remaining spacer elements are the same as those of Example 3-2, and the relevant descriptions in Example 3-2 can be referred to, which will not be described here.

[0151] In summary, the structural parameters of the optical imaging device of Example Three under Example 3-1, Example 3-2 and Example 3-3 are shown in Table 8 (unit: mm).

[0152] Table 8

[0153] ​

[0154]

[0155] In embodiment three, the object side S1 of the first lens is convex, the image side S2 of the first lens is concave. The object side S3 of the second lens is convex, the image side S4 of the second lens is convex. The object side S5 of the third lens is convex, the image side S6 of the third lens is concave. The object side S7 of the fourth lens is convex, the image side S8 of the fourth lens is concave. The object side S9 of the fifth lens is convex, the image side S10 of the fifth lens is convex. The object side S11 of the sixth lens is concave, the image side S12 of the sixth lens is convex. The object side S13 of the seventh lens is convex, the image side S14 of the seventh lens is concave. The object side S15 of the eighth lens is concave, the image side S16 of the eighth lens is concave.

[0156] In embodiment three, the effective focal length f of the optical imaging device is 5.61 mm, the effective focal length f1 of the first lens is 18.69 mm, the effective focal length f2 of the second lens is 5.86 mm, the effective focal length f3 of the third lens is -7.26 mm, the effective focal length f4 of the fourth lens is -28.37 mm, the effective focal length f5 of the fifth lens is 6.85 mm, the effective focal length f6 of the sixth lens is -8.51 mm, the effective focal length f7 of the seventh lens is 5.91 mm, the effective focal length f8 of the eighth lens is -4.52 mm.

[0157] Table 9 shows the basic structure parameter table of the optical imaging device of embodiment three, wherein the units of the radius of curvature, the thickness / distance are millimeter mm. In the following table, OBJ (not shown in the figure) is the object distance. STO (not shown in the figure) is the stop, which is located on the object side of the first lens E1. S17 and S18 (not shown in the figure) can be the object side and the image side of the filter or the object side and the image side of the protection glass. S19 (not shown in the figure) is the imaging surface.

[0158] Table 9

[0159]

[0160]

[0161] The following table 10 gives the high order term coefficients A4, A6, A8, A10, A12, A14, A16, A18 and A20 of each aspheric mirror S1-S16 which can be used in embodiment three. Wherein the surface type of each aspheric lens is defined according to the formula (1) in embodiment one.

[0162] Table 10

[0163]

[0164]

[0165] Figure 19 Figure 21 shows the lateral chromatic aberration curve of the optical imaging device of embodiment three, which represents the deviation of the convergent focus points of light rays of different wavelengths after passing through the imaging lens. Figure 20 Figure 22 shows the on-axis chromatic aberration curve of the optical imaging device of embodiment three, which represents the deviation of the convergent focus points of light rays of different wavelengths after passing through the imaging lens. Figure 21 Figure 23 shows the astigmatism curve of the optical imaging device of embodiment three, which represents the meridional image surface curvature and sagittal image surface curvature. Figure 22 Figure 24 shows the distortion curve of the optical imaging device of embodiment three, which represents the distortion size values corresponding to different image heights.

[0166] According to the above Figures 19 to 22 It can be seen that the optical imaging device given by embodiment three can achieve good imaging quality.

[0167] In summary, embodiments one to three respectively satisfy the relationships shown in Table 11.

[0168] Table 11

[0169] Conditional formula / example 1-1 1-2 1-3 2-1 2-2 2-3 3-1 3-2 3-3 L / ∑CP 9.66 5.19 5.73 9.98 6.39 5.64 10.92 6.20 5.23 R11 / R12 x V6 13.76 13.76 13.76 14.85 14.85 14.85 15.93 15.93 15.93 (EP56 + ∑CP6) / CT6 2.68 2.90 3.05 3.38 3.80 3.88 3.45 3.90 3.80 (d3m + D3m) / R7 1.28 1.54 1.56 1.36 1.63 1.62 0.90 1.11 1.10 d8s / (R15 + R16) 0.33 0.33 0.33 1.25 1.25 1.13 -1.90 -1.87 -1.69 EP23 / EP34 1.42 0.90 1.13 1.38 0.64 1.09 1.28 0.88 1.11 (D7m - d8s) / CT8 1.34 0.12 1.07 1.28 1.08 1.10 1.08 1.22 1.22 (L - ∑AT) / T34 9.87 9.73 9.08 10.33 10.43 10.41 8.65 8.74 8.44 (D6m - d6m) / R13 1.33 0.17 0.17 1.52 1.48 0.37 1.59 1.61 0.38 (D0s - d1s) / CT1 6.78 7.77 7.45 7.95 7.67 7.95 7.78 7.52 7.75 | f6 | / (EP56 + CT6) 6.22 8.06 7.64 5.19 5.84 6.25 4.89 5.56 6.04 f2 x N2 / d2m 3.08 3.04 2.88 4.43 4.41 4.48 3.48 3.46 3.49 ∑EP / EP12 12.39 10.49 11.58 12.79 13.27 11.73 12.70 12.80 10.87 R14 / d7s 1.70 1.48 1.71 1.45 1.45 1.46 0.94 0.93 0.94 R10 x N5 / D5m -2.33 -2.47 -2.43 -1.79 -1.80 -1.98 -1.68 -1.68 -1.74 (EP78 + CP8) / CT8 2.71 2.27 2.36 2.37 2.20 2.04 2.30 2.18 2.17 EP56 / CT6 x R11 -8.54 -5.86 -6.35 -9.58 -8.19 -7.46 -8.52 -7.19 -6.42

[0170] Table 12 shows the effective focal length of the optical imaging devices of embodiments one to three and the effective focal length of each lens and other parameters.

[0171] Table 12

[0172] Basic data / example One Two Three f (mm) 5.39 5.37 5.61 f1 (mm) 24.10 16.93 18.69 f2 (mm) 5.67 7.13 5.86 f3 (mm) -8.37 -8.76 -7.26 f4 (mm) -21.75 -41.19 -28.37 f5 (mm) 8.01 7.22 6.85 f6 (mm) -9.02 -8.88 -8.51 f7 (mm) 4.84 5.21 5.91 f8 (mm) -4.77 -4.63 -4.52

[0173] The present application also provides an imaging device, the electronic photosensitive element of which can be a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS). The imaging device can be a standalone imaging device such as a digital camera, or an imaging module integrated on a mobile electronic device such as a mobile phone. The imaging device is equipped with the optical imaging device described above.

[0174] Obviously, the above described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should fall within the scope of protection of the present application.

[0175] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting, as the scope of the exemplary embodiments of this application is limited only by the appended claims. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. Also, unless otherwise indicated herein, the materials described herein can be used in a variety of applications.

[0176] It should be noted that the terms "first", "second", and the like, as used herein do not necessarily have an ordinal meaning. Rather, such terms are used to distinguish different structures or steps from one another. Terms concerning descriptions of orientations such as "vertical", "horizontal", "top", "bottom", "upper", "lower", and the like are used herein for convenience to describe the exemplary embodiments of this application made in the context of the accompanying drawings. It is to be understood, however, that such terms are not to be construed as limiting the application, unless otherwise explicitly recited in the appended claims.

[0177] The preferred embodiments of the application are described herein with reference to the accompanying drawings, in which the same or similar elements in the drawings are referred to with the same reference numerals. The application is not limited to the preferred embodiments described herein but can be practiced with modification and alteration within the scope of the present application. Accordingly, the specification and drawings are to be regarded as illustrative in nature and explanations in the specification express more by way of non-limiting example.

Claims

1. An optical imaging device, characterized by, The optical imaging device comprises a lens barrel and a lens group and a spacer element group arranged in the lens barrel, the lens group is composed of eight lenses, the eight lenses are in order from the object side to the image side: a first lens with positive refractive power, a second lens with refractive power, a third lens with refractive power, a fourth lens with negative refractive power, a fifth lens with refractive power, a sixth lens with refractive power, a seventh lens with refractive power, and an eighth lens with negative refractive power; the object side surface of the first lens is convex, the image side surface of the fifth lens is convex, the object side surface of the sixth lens is concave, the image side surface of the sixth lens is convex, and the image side surface of the eighth lens is concave; each of the adjacent two lenses in the first lens to the eighth lens has an air gap on the optical axis of the optical imaging device; The spacer element group comprises a first spacer element arranged between the first lens and the second lens and partially abutting against the image side surface of the first lens, a second spacer element arranged between the second lens and the third lens and partially abutting against the image side surface of the second lens, a third spacer element arranged between the third lens and the fourth lens and partially abutting against the image side surface of the third lens, a fourth spacer element arranged between the fourth lens and the fifth lens and partially abutting against the image side surface of the fourth lens, a fifth spacer element arranged between the fifth lens and the sixth lens and partially abutting against the image side surface of the fifth lens, a sixth spacer element arranged between the sixth lens and the seventh lens and partially abutting against the image side surface of the sixth lens, a seventh spacer element arranged between the seventh lens and the eighth lens and partially abutting against the image side surface of the seventh lens, and an eighth spacer element arranged on the image side of the eighth lens and partially abutting against the image side surface of the eighth lens; The maximum axial height L of the lens barrel and the sum ∑CP of the axial thicknesses of all spacer elements of the optical imaging device satisfy: 5.19≤L / ∑CP≤10.92; the curvature radius R11 of the object side surface of the sixth lens, the curvature radius R12 of the image side surface of the sixth lens, and the Abbe number V6 of the sixth lens satisfy: 13.76≤R11 / R12×V6≤15.93; the interval distance EP56 on the optical axis from the image side surface of the fifth spacer element to the object side surface of the sixth spacer element, the sum ∑CP6 of the axial thicknesses of all spacer elements between the sixth lens and the seventh lens, and the central thickness CT6 of the sixth lens on the optical axis satisfy: 2.68≤(EP56+∑CP6) / CT6≤3.

90.

2. The optical imaging device of claim 1, wherein, The object side surface of the fourth lens is convex, the inner diameter d3m of the image side surface of the third spacer element, the outer diameter D3m of the image side surface of the third spacer element, and the curvature radius R7 of the object side surface of the fourth lens satisfy: 0.90≤(d3m+D3m) / R7≤1.

63.

3. The optical imaging device of claim 1, wherein, An inner diameter d8s of an object side surface of the eighth spacer element, a radius of curvature R15 of an object side surface of the eighth lens, and a radius of curvature R16 of an image side surface of the eighth lens satisfy -1.90 ≤ d8s / (R15+R16) ≤ 1.

25.

4. The optical imaging device of claim 1, wherein, A separation distance EP23 on the optical axis of an image side surface of the second spacer element to an object side surface of the third spacer element and a separation distance EP34 on the optical axis of an image side surface of the third spacer element to an object side surface of the fourth spacer element satisfy 0.64 ≤ EP23 / EP34 ≤ 1.

42.

5. The optical imaging device of claim 1, wherein, An outer diameter D7m of an image side surface of the seventh spacer element, an inner diameter d8s of an object side surface of the eighth spacer element, and a central thickness CT8 of the eighth lens on the optical axis satisfy 0.12 ≤ (D7m-d8s) / CT8 ≤ 1.

34.

6. The optical imaging device of claim 1, wherein, A maximum axial height L of the lens barrel, a total sum ∑AT of air gaps of adjacent two lenses among the first to eighth lenses on the optical axis, and an air separation T34 of the third lens and the fourth lens on the optical axis satisfy 8.44 ≤ (L-∑AT) / T34 ≤ 10.

43.

7. The optical imaging device of claim 1, wherein, An object side surface of the seventh lens is a convex surface, an outer diameter D6m of an image side surface of the sixth spacer element, an inner diameter d6m of the image side surface of the sixth spacer element, and a radius of curvature R13 of the object side surface of the seventh lens satisfy 0.17 ≤ (D6m-d6m) / R13 ≤ 1.

61.

8. The optical imaging device of claim 1, wherein, An outer diameter D0s of an object side end surface of the lens barrel, an inner diameter d1s of an object side surface of the first spacer element, and a central thickness CT1 of the first lens on the optical axis satisfy 6.78 ≤ (D0s-d1s) / CT1 ≤ 7.

95.

9. The optical imaging device of claim 1, wherein, The sixth lens has a negative refractive power, an effective focal length f6 of the sixth lens, a separation distance EP56 on the optical axis of an image side surface of the fifth spacer element to an object side surface of the sixth spacer element, and a central thickness CT6 of the sixth lens on the optical axis satisfy 4.89 ≤ |f6| / (EP56+CT6) ≤ 8.

06.

10. The optical imaging device of claim 1, wherein, The second lens has a positive refractive power, an effective focal length f2 of the second lens, a refractive index N2 of the second lens, and an inner diameter d2m of an image side surface of the second spacer element satisfy 2.88 ≤ f2×N2 / d2m ≤ 4.

48.

11. The optical imaging device of claim 1, wherein, A total sum ∑EP of a distance of an object side end surface of the lens barrel to an object side surface of the first spacer element and separation distances on the optical axis of the first spacer element to adjacent two spacer elements among the first to eighth spacer elements and a separation distance EP12 on the optical axis of an image side surface of the first spacer element to an object side surface of the second spacer element satisfy 10.49 ≤ ∑EP / EP12 ≤ 13.

27.

12. The optical imaging device of claim 1, wherein, An image side surface of the seventh lens is a concave surface, a radius of curvature R14 of the image side surface of the seventh lens and an inner diameter d7s of an object side surface of the seventh spacer element satisfy 0.93 ≤ R14 / d7s ≤ 1.

71.

13. The optical imaging device of claim 1, wherein, A relationship among a curvature radius R10 of an image-side surface of the fifth lens, an outer diameter D5m of an image-side surface of the fifth spacer element, and a refractive index N5 of the fifth lens satisfies: -2.47 ≤ R10 x N5 / D5m ≤ -1.

68.

14. The optical imaging device of claim 1, wherein, A relationship among a separation distance EP78 of the image-side surface of the seventh spacer element to the object-side surface of the eighth spacer element, an axial thickness CP8 of the eighth spacer element, and a central thickness CT8 of the eighth lens on the optical axis satisfies: 2.04 ≤ (EP78 + CP8) / CT8 ≤ 2.

71.

15. The optical imaging device according to any one of claims 1 to 14, characterized in that, The spacer element group further includes one or two auxiliary spacer elements disposed between the sixth spacer element and the seventh lens, and a third auxiliary spacer element disposed between the third spacer element and the fourth lens.

16. The optical imaging device according to any one of claims 1 to 14, characterized in that, The third lens has a negative refractive power, the fifth lens has a positive refractive power, and the seventh lens has a positive refractive power; the image-side surface of the first lens is a concave surface, the object-side surface of the second lens is a convex surface, the object-side surface of the third lens is a convex surface, the image-side surface of the third lens is a concave surface, the image-side surface of the fourth lens is a concave surface, and the object-side surface of the fifth lens is a convex surface.

Images