Optical imaging system

Abstract

The application discloses an optical imaging system, which comprises a lens barrel, a lens set and a plurality of spacer elements arranged in the lens barrel, wherein the lens set comprises, in sequence from the object side to the image side along the optical axis, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens and an eighth lens; wherein the effective focal length f4 of the fourth lens, the curvature radius R8 of the image side surface of the fourth lens, the effective focal length f8 of the eighth lens, the curvature radius R15 of the object side surface of the eighth lens and the outer diameter D4s of the object side surface of the fourth spacer element and the outer diameter D7s of the object side surface of the seventh spacer element satisfy 0.3<(f4 / R8+f8 / R15)×(D7s / D4s)<2.5; and the effective focal length f1 of the first lens, the curvature radius R1 of the object side surface of the first lens, the effective focal length f4 of the fourth lens, the curvature radius R8 of the image side surface of the fourth lens, the outer diameter D4s of the object side surface of the fourth spacer element and the inner diameter d4s of the object side surface of the fourth spacer element satisfy 2.0<(f1 / R1+f4 / R8)×(D4s / d4s)<10.0.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of optical elements, in particular, to an optical imaging system. BACKGROUND

[0002] At present, people have higher and higher requirements for the clarity of imaging systems, which puts higher requirements on the assembly of imaging systems. It is essential to study how to provide imaging quality and improve lens stability.

[0003] During the assembly process of the lens, the poor precision of the assembly machine, and the size difference between the lens and the lens barrel will affect the stability of the optical product, causing the lens to deviate from the optical design during the production process, resulting in products that cannot meet the quality requirements. Therefore, under the current conditions, how to reduce the sensitivity of the lens and improve the assembly stability of the lens in production is the key to making the lens have better competitiveness in the industry. SUMMARY

[0004] The first aspect of the present application provides such an optical imaging system, which comprises a lens barrel, a lens group and a plurality of spacer elements arranged in the lens barrel, wherein the lens group comprises, in order from the object side to the image side along the optical axis, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens and an eighth lens; and the plurality of spacer elements comprises a fourth spacer element arranged on the image side of the fourth lens and at least partially in contact with the image side surface of the fourth lens, and a seventh spacer element arranged on the image side of the seventh lens and at least partially in contact with the image side surface of the seventh lens; wherein the refractive index of the first lens among the first to fourth lenses is greater than that of the remaining three lenses; the effective focal length f4 of the fourth lens, the curvature radius R8 of the image side surface of the fourth lens, the effective focal length f8 of the eighth lens, the curvature radius R15 of the object side surface of the eighth lens, and the outer diameter D4s of the object side surface of the fourth spacer element and the outer diameter D7s of the object side surface of the seventh spacer element satisfy: 0.3<(f4 / R8+f8 / R15)×(D7s / D4s)<2.5; and the effective focal length f1 of the first lens, the curvature radius R1 of the object side surface of the first lens, the effective focal length f4 of the fourth lens, the curvature radius R8 of the image side surface of the fourth lens, the outer diameter D4s of the object side surface of the fourth spacer element and the inner diameter d4s of the object side surface of the fourth spacer element satisfy: 2.0<(f1 / R1+f4 / R8)×(D4s / d4s)<10.0.

[0005] The second aspect of the present application provides such an optical imaging system, comprising: a lens barrel, and a lens set and a plurality of spacer elements disposed in the lens barrel, wherein the lens set comprises, in order from the object side to the image side along the optical axis: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens; and the plurality of spacer elements comprises: a first spacer element disposed on the image side of the first lens and at least partially in contact with the image side surface of the first lens; and a second spacer element disposed on the image side of the second lens and at least partially in contact with the image side surface of the second lens; wherein the refractive index of the first lens among the first to fourth lenses is greater than the refractive index of the remaining three lenses; the radius of curvature R1 of the object side surface of the first lens, the radius of curvature R2 of the image side surface of the first lens, the central thickness CT1 of the first lens on the optical axis, the air gap T12 of the first lens and the second lens on the optical axis, and the distance EP12 between the image side surface of the first spacer element and the object side surface of the second spacer element along the optical axis direction satisfy: -15.0 < (R1+R2) / (CT1+T12+EP12) < -3.0.

[0006] The third aspect of the present application provides such an optical imaging system, comprising: a lens barrel, and a lens set and a plurality of spacer elements disposed in the lens barrel, wherein the lens set comprises, in order from the object side to the image side along the optical axis: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens; and the plurality of spacer elements further comprises: a first spacer element disposed on the image side of the first lens and at least partially in contact with the image side surface of the first lens; a second spacer element disposed on the image side of the second lens and at least partially in contact with the image side surface of the second lens; and a third spacer element disposed on the image side of the third lens and at least partially in contact with the image side surface of the third lens; wherein the refractive index of the first lens among the first to fourth lenses is greater than the refractive index of the remaining three lenses; the radius of curvature R2 of the image side surface of the first lens, the radius of curvature R3 of the object side surface of the second lens, the radius of curvature R4 of the image side surface of the second lens, the radius of curvature R5 of the object side surface of the third lens, the outer diameter D1s of the object side surface of the first spacer element, the outer diameter D2s of the object side surface of the second spacer element, and the outer diameter D3s of the object side surface of the third spacer element satisfy: 40.0 < (R2+R3) / (D2s-D1s)+(R4+R5) / (D3s-D2s) < 50.0.

[0007] In one embodiment, the plurality of spacer elements further comprises: a first spacer element disposed on the image side of the first lens and at least partially in contact with the image side surface of the first lens; and a second spacer element disposed on the image side of the second lens and at least partially in contact with the image side surface of the second lens; wherein the effective focal length f1 of the first lens, the effective focal length f2 of the second lens, the inner diameter d1m of the image side surface of the first spacer element, the inner diameter d2m of the image side surface of the second spacer element, the Abbe number V1 of the first lens, and the Abbe number V2 of the second lens satisfy: 3.0 < (V2-V1) / (f1 / d1m+f2 / d2m) < 20.0.

[0008] In one embodiment, the plurality of spacer elements further comprises: a first spacer element disposed on the image side of the first lens and at least partially in contact with the image side surface of the first lens; and a second spacer element disposed on the image side of the second lens and at least partially in contact with the image side surface of the second lens; wherein the radius of curvature R1 of the object side surface of the first lens, the radius of curvature R2 of the image side surface of the first lens, the central thickness CT1 of the first lens on the optical axis, the air separation T12 of the first lens and the second lens on the optical axis, and the distance EP12 of the image side surface of the first spacer element and the object side surface of the second spacer element along the optical axis direction satisfy: -15.0 < (R1+R2) / (CT1+T12+EP12) < -3.0.

[0009] In one embodiment, the plurality of spacer elements further comprises: a first spacer element disposed on the image side of the first lens and at least partially in contact with the image side surface of the first lens; a second spacer element disposed on the image side of the second lens and at least partially in contact with the image side surface of the second lens; and a third spacer element disposed on the image side of the third lens and at least partially in contact with the image side surface of the third lens; wherein the radius of curvature R2 of the image side surface of the first lens, the radius of curvature R3 of the object side surface of the second lens, the radius of curvature R4 of the image side surface of the second lens, the radius of curvature R5 of the object side surface of the third lens, the outer diameter D1s of the object side surface of the first spacer element, the outer diameter D2s of the object side surface of the second spacer element, and the outer diameter D3s of the object side surface of the third spacer element satisfy: 40.0 < (R2+R3) / (D2s-D1s)+(R4+R5) / (D3s-D2s) < 50.0.

[0010] In one embodiment, the plurality of spacer elements further comprises: a first spacer element disposed on the image side of the first lens and at least partially in contact with the image side surface of the first lens; wherein the central thickness CT1 of the first lens on the optical axis, the effective focal length f1 of the first lens, the distance EP01 of the object side surface of the barrel to the object side surface of the first spacer element along the optical axis direction, the inner diameter d0s of the object side surface of the barrel, and the inner diameter d1s of the object side surface of the first spacer element satisfy: |(EP01-CT1)xf1| / [(d0s-d1s)xf] < 10.0.

[0011] In one embodiment, the plurality of spacer elements further comprises: a fifth spacer element disposed on the image side of the fifth lens and at least partially in contact with the image side surface of the fifth lens; wherein the radius of curvature R8 of the image side surface of the fourth lens, the radius of curvature R9 of the object side surface of the fifth lens, the central thickness CT4 of the fourth lens along the optical axis, the central thickness CT5 of the fifth lens along the optical axis, the air separation T45 of the fourth lens and the fifth lens along the optical axis, the outer diameter D4s of the object side surface of the fourth spacer element, and the outer diameter D5s of the object side surface of the fifth spacer element satisfy: -10.0 < (R9 / D5s-R8 / D4s) x T45 / (CT4+CT5) < 10.0.

[0012] In one embodiment, the plurality of spacer elements further comprises: a second spacer element disposed on the image side of the second lens and at least partially in contact with the image side surface of the second lens; a third spacer element disposed on the image side of the third lens and at least partially in contact with the image side surface of the third lens; wherein the effective focal length f2 of the second lens, the effective focal length f3 of the third lens, the refractive index N2 of the second lens, the refractive index N3 of the third lens, the inner diameter d2s of the object side surface of the second spacer element, and the inner diameter d3s of the object side surface of the third spacer element satisfy: 8.0 < (f2+f3) x (N2+N3) / (d2s+d3s) < 20.0.

[0013] In one embodiment, the plurality of spacer elements further comprises: a fifth spacer element disposed on the image side of the fifth lens and at least partially in contact with the image side surface of the fifth lens; a sixth spacer element disposed on the image side of the sixth lens and at least partially in contact with the image side surface of the sixth lens; wherein the inner diameter d5m of the image side surface of the fifth spacer element, the inner diameter d6s of the object side surface of the sixth spacer element, the radius of curvature R10 of the image side surface of the fifth lens, the radius of curvature R11 of the object side surface of the sixth lens, the Abbe number V5 of the fifth lens, and the Abbe number V6 of the sixth lens satisfy: 25.0 < (d5m+d6s) / (R10 / V5+R11 / V6) < 70.0.

[0014] In one embodiment, the plurality of spacer elements further comprises: a second spacer element disposed on the image side of the second lens and at least partially in contact with the image side surface of the second lens; a third spacer element disposed on the image side of the third lens and at least partially in contact with the image side surface of the third lens; wherein the combined focal length f12 of the first lens and the second lens, the combined focal length f34 of the third lens and the fourth lens, the distance EP23 between the image side surface of the second spacer element and the object side surface of the third spacer element along the optical axis, the maximum thickness CP2 of the second spacer element along the optical axis, and the maximum thickness CP3 of the third spacer element along the optical axis satisfy: -50.0 < (f12+f34) / (EP23+CP2+CP3) < 0.

[0015] In an embodiment, the plurality of spacer elements further comprises: a sixth spacer element disposed on the image side of the sixth lens and at least partially in contact with the image side surface of the sixth lens; an eighth spacer element disposed on the image side of the eighth lens and at least partially in contact with the image side surface of the eighth lens; wherein the inner diameter d6m of the image side surface of the sixth spacer element, the inner diameter d7m of the image side surface of the seventh spacer element, the inner diameter d8m of the image side surface of the eighth spacer element, the effective focal length f6 of the sixth lens, the effective focal length f7 of the seventh lens, and the effective focal length f8 of the eighth lens satisfy: d6m / |f6| + d7m / |f7| + d8m / |f8| < 10.0.

[0016] In an embodiment, the plurality of spacer elements further comprises: a sixth spacer element disposed on the image side of the sixth lens and at least partially in contact with the image side surface of the sixth lens; wherein the radius of curvature R12 of the image side surface of the sixth lens, the radius of curvature R13 of the object side surface of the seventh lens, the central thickness CT6 of the sixth lens on the optical axis, 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 maximum thickness CP6 of the sixth spacer element along the direction of the optical axis satisfy: -50.0 < (R12-R13) x T67 / [(D6m-d6m) x CP6] < 0.

[0017] In an embodiment, the plurality of spacer elements further comprises: a fifth spacer element disposed on the image side of the fifth lens and at least partially in contact with the image side surface of the fifth lens; wherein the inner diameter d4m of the image side surface of the fourth spacer element, the outer diameter D4m of the image side surface of the fourth spacer element, the inner diameter d5s of the object side surface of the fifth spacer element, the outer diameter D5s of the object side surface of the fifth spacer element, the radius of curvature R9 of the object side surface of the fifth lens, and the radius of curvature R10 of the image side surface of the fifth lens satisfy: -50.0 < (D5s-d5s) x R10 - (D4m-d4m) x R9 < 50.0.

[0018] In an embodiment, the effective focal length f1 of the first lens, the refractive index N1 of the first lens, the effective focal length f4 of the fourth lens, and the refractive index N4 of the fourth lens satisfy: f1 / N1 < -1.0 mm and 3.0 mm < |f4 / N4|.

[0019] In an embodiment, the plurality of spacer elements further comprises: a first spacer element disposed on the image side of the first lens and at least partially in contact with the image side surface of the first lens; wherein the maximum effective radius DT11 of the object side surface of the first lens, the maximum effective radius DT12 of the image side surface of the first lens, the inner diameter d1s of the object side surface of the first spacer element, and the inner diameter d1m of the image side surface of the first spacer element satisfy: 2.0 < (DT11-DT12) / (d1s-d1m) < 12.0.

[0020] In one embodiment, the minimum inner diameter d0min of the front end portion of the lens barrel facing the object side and the maximum field of view FOV of the optical imaging system satisfy: d0min / tan(FOV / 2) > 5.0 mm.

[0021] In one embodiment, the plurality of spacer elements further comprises: an eighth spacer element disposed on the image side of the eighth lens and at least partially in contact with the image side surface of the eighth lens; wherein the radius of curvature R15 of the object side surface of the eighth lens, the radius of curvature R16 of the image side surface of the eighth lens, the maximum outer diameter D8max of the eighth spacer element and the minimum inner diameter d8min of the eighth spacer element satisfy: -30.0 < (R15-R16) / (D8max-d8min) < -10.0.

[0022] The optical imaging system provided in the present application comprises eight lenses and a plurality of spacer elements. The use of the plurality of spacer elements can block the reflected light in the lens, avoid the generation of stray light, and improve the imaging performance of the lens in production. Specifically, the optical imaging system of the present application can satisfy: 0.3 < (f4 / R8+f8 / R15) x (D7s / D4s) < 2.5 and 2.0 < (f1 / R1+f4 / R8) x (D4s / d4s) < 10.0. Among the first four lenses, the refractive index of the first lens is large. For a lens made of high refractive index material, the light turning angle is too large, causing the first lens to have high sensitivity. At the same time, the center thickness of the eighth lens is small, the edge thickness is large, and the bending degree is large, so the processing sensitivity is high. The present application controls the effective focal length of the first lens and the radius of curvature of the object side surface of the first lens, the effective focal length of the fourth lens and the radius of curvature of the image side surface of the fourth lens, and the effective focal length of the eighth lens and the radius of curvature of the object side surface of the eighth lens, so that the light is focused, which is conducive to the arrangement and structural adjustment of the first lens, the fourth lens and the eighth lens. When the light is incident into the first lens and reaches the image side surface of the eighth lens, the total deflection angle of the field of view on the object side surface of the first lens and the image side surface of the fourth lens can be reasonably controlled within 2 min (within the inclination angle range of 2'). At the same time, it helps to reduce the sensitivity of the assembly of the fourth lens and the eighth lens, thereby reducing the influence of the lens assembly performance stability at this position. BRIEF DESCRIPTION OF DRAWINGS

[0023] Other features, objects, and advantages of the present application will become more apparent from the following detailed description of non-limiting embodiments made with reference to the following drawings:

[0024] Figure 1 The structural arrangement diagram of an optical imaging system according to the present application and the schematic diagram of part of the parameters are shown;

[0025] Figures 2A to 2CA structural diagram of an optical imaging system according to Embodiment 1 of the present application is shown.

[0026] Figures 3A to 3D An on-axis chromatic aberration curve, an astigmatism curve, a distortion curve, and a magnification chromatic aberration curve of the optical imaging system according to Embodiment 1 of the present application are shown, respectively.

[0027] Figures 4A to 4C A structural diagram of an optical imaging system according to Embodiment 2 of the present application is shown.

[0028] Figures 5A to 5D An on-axis chromatic aberration curve, an astigmatism curve, a distortion curve, and a magnification chromatic aberration curve of the optical imaging system according to Embodiment 2 of the present application are shown, respectively.

[0029] Figures 6A to 6C A structural diagram of an optical imaging system according to Embodiment 3 of the present application is shown.

[0030] Figures 7A to 7D An on-axis chromatic aberration curve, an astigmatism curve, a distortion curve, and a magnification chromatic aberration curve of the optical imaging system according to Embodiment 3 of the present application are shown, respectively. DETAILED DESCRIPTION

[0031] For a better understanding of the present application, various aspects of the present application will be described in more detail below with reference to the accompanying drawings. It is to be noted that the detailed description is only a description of exemplary embodiments of the present application and is in no way limiting on the scope of the present application. Throughout the specification, like drawing reference numerals refer to like elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0032] It is to be noted that, in the present specification, the expressions first, second, third, etc. are used only to distinguish one feature from another feature, and do not indicate any limitation on the features. Thus, the first lens discussed below can also be referred to as the second lens or the third lens without departing from the teachings of the present application.

[0033] In the drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for ease of explanation. Specifically, the shape of the spherical surface or the aspherical surface shown in the drawings is shown by way of example. That is, the shape of the spherical surface or the aspherical surface is not limited to the shape of the spherical surface or the aspherical surface shown in the drawings. The drawings are merely examples and are not drawn to scale.

[0034] In the present disclosure, the paraxial region refers to a region near the optical axis. If a lens surface is convex and the position of the convex surface is not specified, it means that the lens surface is convex at least in the paraxial region. If a lens surface is concave and the position of the concave surface is not specified, it means that the lens surface is concave at least in the paraxial region. The surface of each lens close to the object is referred to as the object side surface of the lens, and the surface of each lens close to the image plane is referred to as the image side surface of the lens.

[0035] It should also be understood that the use of the terms "including", "comprising", "having" "with" and / or "contains", when used in this specification, specify the presence of stated features, elements and / or components, but do not preclude the presence or addition of one or more other features, elements, components and / or their combinations. In addition, when expressions such as "at least one of" appear after a list of items, it modifies the entire list of items and not the individual items in the list. In addition, when describing embodiments of the present application, the use of "may" means "one or more embodiments of the present application". And the term "exemplary" is intended to refer to an example or illustration.

[0036] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It should also be understood that terms (such as those defined in commonly used dictionaries) should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0037] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The following embodiments only express several embodiments of the present application, which are described in detail and specifically, but cannot be construed as limiting the scope of the patent of the present application. It should be noted that for those skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of protection of the present application, for example, the lens group, the lens barrel and the spacer element in each embodiment of the present application can be combined arbitrarily, which is not limited to the combination of the lens group in one embodiment with the lens barrel, the spacer element and the like in the embodiment.

[0038] The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments. Figure 1 The structural arrangement diagram of an optical imaging system according to the present application and the schematic diagram of some parameters are shown. Those skilled in the art should understand that some parameters of lenses commonly used in the art, such as the center thickness CT1 of the first lens on the optical axis, are not shown in the drawings, Figure 1 . Figure 1Some of the parameters of the lens barrel and the spacer elements of an optical imaging system according to the present application are shown by way of example only to facilitate better understanding of the present application, such as Figure 1 As shown, CP3 is the maximum thickness of the third spacer element in the direction of the optical axis, EP12 is the distance between the image-side surface of the first spacer element and the object-side surface of the second spacer element in the direction of the optical axis, EP01 is the distance between the object-side end surface of the lens barrel and the object-side surface of the first spacer element in the direction of the optical axis, d1s is the inner diameter of the object-side surface of the first spacer element, d1m is the inner diameter of the image-side surface of the first spacer element, D4s is the outer diameter of the object-side surface of the fourth spacer element, d4s is the inner diameter of the object-side surface of the fourth spacer element, d0min is the minimum inner diameter of the front end portion of the lens barrel facing the object side, D8max is the maximum outer diameter of the eighth spacer element, and d8min is the minimum inner diameter of the eighth spacer element.

[0039] An optical imaging system according to an exemplary embodiment of the present application includes a lens barrel, and a plurality of spacer elements disposed in the lens barrel. The lens barrel includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens arranged in order from an object side to an image side along an optical axis.

[0040] In an exemplary embodiment, the plurality of spacer elements can include at least one of a first spacer element, a second spacer element, a third spacer element, a fourth spacer element, a fifth spacer element, a sixth spacer element, a seventh spacer element, and an eighth spacer element; wherein the first spacer element is disposed on the image side of the first lens and at least partially contacts the image-side surface of the first lens, the second spacer element is disposed on the image side of the second lens and at least partially contacts the image-side surface of the second lens, the third spacer element is disposed on the image side of the third lens and at least partially contacts the image-side surface of the third lens, the fourth spacer element is disposed on the image side of the fourth lens and at least partially contacts the image-side surface of the fourth lens, the fifth spacer element is disposed on the image side of the fifth lens and at least partially contacts the image-side surface of the fifth lens, the sixth spacer element is disposed on the image side of the sixth lens and at least partially contacts the image-side surface of the sixth lens, the seventh spacer element is disposed on the image side of the seventh lens and at least partially contacts the image-side surface of the seventh lens, and the eighth spacer element is disposed on the image side of the eighth lens and at least partially contacts the image-side surface of the eighth lens.

[0041] In an exemplary embodiment, the plurality of spacer elements includes the fourth spacer element disposed on the image side of the fourth lens and at least partially contacting the image-side surface of the fourth lens, and the seventh spacer element disposed on the image side of the seventh lens and at least partially contacting the image-side surface of the seventh lens.

[0042] It should be understood that the number of spacer elements is not specifically limited in the present application, and any number of spacer elements can be included between any two lenses, and any number of spacer elements can be included in the entire optical imaging system. The spacer elements help the optical imaging system to intercept the excess catadioptric optical path, and reduce the generation of stray light and ghosting. The addition of auxiliary abutments between the spacer elements and the lens barrel helps to improve the poor assembly stability and low performance yield caused by large gaps between lenses.

[0043] In an exemplary embodiment, the effective focal length f1 of the first lens and the refractive index N1 of the first lens can satisfy: f1 / N1 <-1.0 mm. More specifically, the optical imaging system according to the present application can further satisfy: -15.0 mm < f1 / N1 < -1.0 mm.

[0044] In an exemplary embodiment, the effective focal length f4 of the fourth lens and the refractive index N4 of the fourth lens can satisfy: 3.0 mm < |f4 / N4|. More specifically, the optical imaging system according to the present application can further satisfy: 3.0 mm < |f4 / N4| < 25 mm.

[0045] In an exemplary embodiment, the optical imaging system according to the present application can satisfy: 0.3 < (f4 / R8+f8 / R15) x (D7s / D4s) < 2.5, where f4 is the effective focal length of the fourth lens, R8 is the curvature radius of the image side surface of the fourth lens, f8 is the effective focal length of the eighth lens, R15 is the curvature radius of the object side surface of the eighth lens, D4s is the outer diameter of the object side surface of the fourth spacer element, and D7s is the outer diameter of the object side surface of the seventh spacer element.

[0046] In an exemplary embodiment, the optical imaging system according to the present application can satisfy: 2.0 < (f1 / R1+f4 / R8) x (D4s / d4s) < 10.0, where f1 is the effective focal length of the first lens, R1 is the curvature radius of the object side surface of the first lens, f4 is the effective focal length of the fourth lens, R8 is the curvature radius of the image side surface of the fourth lens, D4s is the outer diameter of the object side surface of the fourth spacer element, and d4s is the inner diameter of the object side surface of the fourth spacer element.

[0047] In an example embodiment, the optical imaging system according to the present application comprises: a lens barrel, and a lens group and a plurality of spacer elements disposed in the lens barrel, wherein the lens group comprises, in order from the object side to the image side along the optical axis: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens; and the plurality of spacer elements further comprises: a first spacer element disposed on the image side of the first lens and at least partially in contact with the image side surface of the first lens; a second spacer element disposed on the image side of the second lens and at least partially in contact with the image side surface of the second lens; and a third spacer element disposed on the image side of the third lens and at least partially in contact with the image side surface of the third lens; wherein the refractive index of the first lens among the first to fourth lenses is greater than the refractive index of the remaining three lenses, and the optical imaging system according to the present application can satisfy: 0.3 < (f4 / R8 + f8 / R15) x (D7s / D4s) < 2.5 and 2.0 < (f1 / R1 + f4 / R8) x (D4s / d4s) < 10.0, by controlling the effective focal length of the first lens and the radius of curvature of the object side surface of the first lens, the effective focal length of the fourth lens and the radius of curvature of the image side surface of the fourth lens, and the effective focal length of the eighth lens and the radius of curvature of the object side surface of the eighth lens, the light rays are focused, which is conducive to the arrangement and structural adjustment of the first lens, the fourth lens, and the eighth lens. Since the refractive index of the first lens among the first four lenses is relatively large, for lenses made of high refractive index material, the light ray turning angle is too large, causing the first lens to be sensitive. At the same time, the center thickness of the eighth lens is smaller than the edge thickness, and the curvature of the eighth lens is large, so the processing sensitivity is high. Through the setting of the above condition formula, when the light rays enter the first lens and reach the image side surface of the eighth lens, the total deflection angle of the field of view on the object side surface of the first lens and the image side surface of the fourth lens can be reasonably controlled within 2 min (2' inclination angle range), which helps to reduce the sensitivity of the assembly of the first lens, the fourth lens, and the eighth lens, thereby reducing the impact of the lens assembly performance stability at this position.

[0048] In the example embodiment, the optical imaging system according to the present application can satisfy: 3.0 < (V2-V1) / (f1 / d1m+f2 / d2m) < 20.0, where f1 is the effective focal length of the first lens, f2 is the effective focal length of the second lens, d1m is the inner diameter of the image side surface of the first spacer element, d2m is the inner diameter of the image side surface of the second spacer element, V1 is the dispersion coefficient of the first lens, and V2 is the dispersion coefficient of the second lens. By controlling the effective focal lengths of the first lens and the second lens, the lens structure can be compact, and the total height of the lens is smaller. The larger the imaging, the more image points are required. In a compact structure lens, a large dispersion coefficient is required to control the imaging area (too large will cause the Abbe number to be too large, resulting in blurred imaging). The larger the image, the greater the light quantity required. By f1 / d1m+f2 / d2m, the light quantity can be controlled, the illumination of the imaging will be better, and the brightness required by the vision will be met. Satisfying the condition formula, the ratio of the difference between the dispersion coefficients of the first lens and the second lens and f1 / d1m+f2 / d2m can make the imaging system more clear and the overall imaging quality of the system better. The inner diameter of the image side surface of the first spacer element and the inner diameter of the image side surface of the second spacer element can block stray light generated by the light path reflected by the edge mechanism of the effective diameter of the object side surface of the first lens and the second lens to the inside of the lens, thereby improving the imaging quality.

[0049] In the example embodiment, the optical imaging system according to the present application can satisfy: -15.0 < (R1+R2) / (CT1+T12+EP12) < -3.0, where R1 is the curvature radius of the object side surface of the first lens, R2 is the curvature radius of the image side surface of the first lens, CT1 is the central thickness of the first lens on the optical axis, T12 is the air gap between the first lens and the second lens on the optical axis, and EP12 is the distance between the image side surface of the first spacer element and the object side surface of the second spacer element along the optical axis. By controlling the curvature radius and the central thickness of the first lens, the spacing distance between the first lens and the second lens, and the parameter relationship between the spacing distance of the first spacer element and the second spacer element, the assembly gap of the first lens and the second lens position lens can be controlled, the field curvature of the lens can be ensured within a certain range of variation, the sensitivity of the optical system of the lens can be reduced, and the assembly yield of the lens can be improved.

[0050] In the exemplary embodiments, the optical imaging system according to the present application satisfies: 40.0 < (R2+R3) / (D2s-D1s)+(R4+R5) / (D3s-D2s) < 50.0, where R2 is the curvature radius of the image side surface of the first lens, R3 is the curvature radius of the object side surface of the second lens, R4 is the curvature radius of the image side surface of the second lens, R5 is the curvature radius of the object side surface of the third lens, D1s is the outer diameter of the object side surface of the first spacer element, D2s is the outer diameter of the object side surface of the second spacer element, and D3s is the outer diameter of the object side surface of the third spacer element. The present application controls the curvature radius of the image side surface of the first lens, the curvature radius of the object side surface of the second lens, the curvature radius of the image side surface of the second lens, the curvature radius of the object side surface of the third lens, and the outer diameters of the first, second, and third spacer elements, which can avoid stray light and ghost images caused by one or more reflections of the light rays outside the effective diameter of the first, second, and third lenses in the effective diameter part and the non-effective diameter part of the lens structure.

[0051] In the exemplary embodiments, the optical imaging system according to the present application satisfies: |(EP01-CT1)xf1| / [(d0s-d1s)x f] < 10.0, where CT1 is the central thickness of the first lens on the optical axis, f1 is the effective focal length of the first lens, EP01 is the distance from the object side end surface of the lens barrel to the object side surface of the first spacer element along the optical axis, d0s is the inner diameter of the object side end surface of the lens barrel, and d1s is the inner diameter of the object side surface of the first spacer element. More specifically, the optical imaging system according to the present application further satisfies: 1.0 < |(EP01-CT1)xf1| / [(d0s-d1s)x f] < 5.0. The present application controls the inner diameter of the object side end surface of the lens barrel and the inner diameter of the object side surface of the first spacer element, which can reasonably control the influence of the first lens on the overall optical power under the premise that the light rays passing through the center of the optical axis of the lens satisfy the relative luminance of the off-axis field, reduce the on-axis space of the first lens in the lens barrel, thereby helping to leave a larger degree of freedom for the reasonable design of different optical powers of subsequent lenses, and also being conducive to the arrangement of a compact lens structure.

[0052] In exemplary embodiments, the optical imaging system according to the present application can satisfy: -10.0 < (R9 / D5s-R8 / D4s) x T45 / (CT4+CT5) < 10.0, where R8 is the radius of curvature of the image side surface of the fourth lens, R9 is the radius of curvature of the object side surface of the fifth lens, CT4 is the central thickness of the fourth lens on the optical axis, CT5 is the central thickness of the fifth lens on the optical axis, T45 is the air interval of the fourth lens and the fifth lens on the optical axis, D4s is the outer diameter of the object side surface of the fourth spacer element, and D5s is the outer diameter of the object side surface of the fifth spacer element. The present application controls the radius of curvature of the image side surface of the fourth lens, the radius of curvature of the object side surface of the fifth lens, the central thickness of the fourth lens on the optical axis, the central thickness of the fifth lens on the optical axis, and the air interval of the fourth lens and the fifth lens on the optical axis, so that the lens can have a deviation range of 2° for 1.0 field angle of view rays under the condition of meeting the imaging quality, effectively reduces the sensitivity of the system, and improves the stability of the quality in the assembly process.

[0053] In exemplary embodiments, the optical imaging system according to the present application can satisfy: 8.0 < (f2+f3) x (N2+N3) / (d2s+d3s) < 20.0, where f2 is the effective focal length of the second lens, f3 is the effective focal length of the third lens, N2 is the refractive index of the second lens, N3 is the refractive index of the third lens, d2s is the inner diameter of the object side surface of the second spacer element, and d3s is the inner diameter of the object side surface of the third spacer element. The present application controls the focal length and refractive index of the second lens and the third lens within a reasonable range to meet the optical requirements, improves the imaging quality of the lens in the case of compact structure, and avoids the formation of stray light and ghost images by one or more reflections of the excess light rays outside the effective diameter of the lens in the structure part of the effective diameter of the lens and the non-effective diameter of the lens.

[0054] In the exemplary embodiments, the optical imaging system according to the present application can satisfy: 25.0 < (d5m+d6s) / (R10 / V5+R11 / V6) < 70.0, where d5m is the image-side inner diameter of the fifth spacer element, d6s is the object-side inner diameter of the sixth spacer element, R10 is the curvature radius of the image-side surface of the fifth lens, R11 is the curvature radius of the object-side surface of the sixth lens, V5 is the dispersion coefficient of the fifth lens, and V6 is the dispersion coefficient of the sixth lens. Satisfying 25.0 < (d5m+d6s) / (R10 / V5+R11 / V6) < 70.0 can reasonably control the refraction angle of light passing through the corresponding lens by controlling the ratio of the curvature radius of the image-side surface of the fifth lens and the curvature radius of the object-side surface of the sixth lens within a certain range, so that the cooperation of the lenses is more compact. Controlling the inner diameters of the fifth and sixth spacer elements mainly aims to avoid stray light caused by the light reflected by the mechanism of the fourth lens near the edge of the effective diameter of the object-side surface reaching the inside of the lens.

[0055] In the exemplary embodiments, the optical imaging system according to the present application can satisfy: -50.0 < (f12+f34) / (EP23+CP2+CP3) < 0, where f12 is the combined focal length of the first lens and the second lens, f34 is the combined focal length of the third lens and the fourth lens, EP23 is the distance between the image-side surface of the second spacer element and the object-side surface of the third spacer element along the optical axis, CP2 is the maximum thickness of the second spacer element along the optical axis, and CP3 is the maximum thickness of the third spacer element along the optical axis. Satisfying -50.0 < (f12+f34) / (EP23+CP2+CP3) < 0 can control the contribution value of the aberration of the two lenses by reasonably controlling the combined focal length of the first lens and the second lens within a certain range, balance the aberration generated by the front optical elements, and make the system aberration at a reasonable level. Controlling the thickness of EP23 and the second and third spacer elements can make them reach the best forming conditions and assembly stability within a certain range.

[0056] In an exemplary embodiment, the optical imaging system according to the present application can satisfy: d6m / |f6|+d7m / |f7|+d8m / |f8|<10.0, where d6mis the inner diameter of the image side surface of the sixth spacer element, d7mis the inner diameter of the image side surface of the seventh spacer element, d8mis the inner diameter of the image side surface of the eighth spacer element, f6is the effective focal length of the sixth lens, f7is the effective focal length of the seventh lens, and f8is the effective focal length of the eighth lens. More specifically, the optical imaging system according to the present application can further satisfy: 3.0<d6m / |f6|+d7m / |f7|+d8m / |f8|<5.0. Satisfying d6m / |f6|+d7m / |f7|+d8m / |f8|<10.0 controls the inner diameter of the sixth spacer element and the effective focal length, so that the light intensity of the off-axis field of view satisfies the optical system, while the effective focal length of the seventh lens and the eighth lens has sufficient adjustment space, and the light rays that are blocked by the seventh lens and the eighth lens position are reflected within the effective lens to generate stray light.

[0057] In an exemplary embodiment, the optical imaging system according to the present application can satisfy: -50.0<(R12-R13) x T67 / [(D6m-d6m) x CP6]<0, where R12is the radius of curvature of the image side surface of the sixth lens, R13is the radius of curvature of the object side surface of the seventh lens, CT6is the center thickness of the sixth lens on the optical axis, D6mis the outer diameter of the image side surface of the sixth spacer element, d6mis the inner diameter of the image side surface of the sixth spacer element, and CP6is the maximum thickness of the sixth spacer element in the direction of the optical axis. Satisfying -50.0<(R12-R13) x T67 / [(D6m-d6m) x CP6]<0 controls the radius of curvature of the image side surface of the sixth lens and the radius of curvature of the object side surface of the seventh lens, so that the air gap of the sixth lens and the seventh lens along the optical axis is adjusted, and the center thickness of the sixth lens and the seventh lens is controlled; the thickness of the sixth spacer element can be reduced within a certain range that satisfies the optical performance, and the structure of the lens barrel that meets the requirements of compactness in lens design is satisfied.

[0058] In exemplary embodiments, the optical imaging system according to the present application can satisfy: -50.0 < (D5s-d5s) x R10-(D4m-d4m) x R9< 50.0, where d4mis the inner diameter of the image side surface of the fourth spacer element, D4mis the outer diameter of the image side surface of the fourth spacer element, d5sis the inner diameter of the object side surface of the fifth spacer element, D5s is the outer diameter of the object side surface of the fifth spacer element, R9is the radius of curvature of the object side surface of the fifth lens, and R10is the radius of curvature of the image side surface of the fifth lens. More specifically, the optical imaging system according to the present application can further satisfy: -20.0 < (D5s-d5s) x R10-(D4m-d4m) x R9< 30.0. Satisfying -50.0 < (D5s-d5s) x R10-(D4m-d4m) x R9< 50.0 controls the radii of curvature of the object side surface and the image side surface of the fifth lens, which can make the lens better controlled in molding, and at the same time, the inner diameter and the outer diameter of the image side surfaces of the fourth spacer element and the fifth spacer element satisfy the requirements, so that the structure is better adjusted in the imaging system, which is conducive to avoiding stray light generated by internal total reflection.

[0059] In exemplary embodiments, the optical imaging system according to the present application can satisfy: 2.0 < (DT11-DT12) / (d1s-d1m)< 12.0, where DT11is the maximum effective radius of the object side surface of the first lens, DT12is the maximum effective radius of the image side surface of the first lens, d1sis the inner diameter of the object side surface of the first spacer element, and d1mis the inner diameter of the image side surface of the first spacer element. The present application controls the maximum effective radius of the object side surface of the first lens and the maximum effective radius of the image side surface of the first lens to ensure the aperture size, so that the inner diameter of the object side surface of the first spacer element and the inner diameter of the image side surface of the first spacer element block light rays in the lens barrel, thereby avoiding excessive light rays passing through the rear lens, which causes excessive stray light to be generated during imaging.

[0060] In exemplary embodiments, the optical imaging system according to the present application can satisfy: d0min / tan(FOV / 2)>5.0mm, where d0min is the minimum inner diameter of the front end portion of the lens barrel facing the object side, and FOV is the maximum field of view angle of the optical imaging system. More specifically, the optical imaging system according to the present application can further satisfy: 6.0 < d0min / tan(FOV / 2)< 7.0. Satisfying d0min / tan(FOV / 2)>5.0mm can effectively control the minimum inner diameter of the lens barrel and the maximum field of view angle of the optical imaging system, ensure the field of view angle of the imaging lens, effectively reduce the size of the imaging system, ensure the optical performance of the system, and at the same time, make it easier to process and stably assemble the accessories under the premise of satisfying the light flux.

[0061] In the example embodiment, the optical imaging system according to the present application can satisfy: -30.0 < (R15-R16) / (D8max-d8min) < -10.0, where R15 is the radius of curvature of the object side surface of the eighth lens, R16 is the radius of curvature of the image side surface of the eighth lens, D8max is the maximum outer diameter of the eighth spacer element, and d8min is the minimum inner diameter of the eighth spacer element. Satisfying -30.0 < (R15-R16) / (D8max-d8min) < -10.0 can control the radii of curvature of the object side surface and the image side surface of the eighth lens, so that the imaging system can ensure the adjustability of the front lens in structure, can control the corner of the edge field surface, can reduce the sensitivity of the lens within a certain range, and can block light to avoid the generation of ghost images.

[0062] In the example embodiment, the optical imaging system according to the present application comprises a lens barrel, a lens group and a plurality of spacer elements disposed in the lens barrel, wherein the lens group comprises, in order from the object side to the image side along the optical axis, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens and an eighth lens; and the plurality of spacer elements comprises a fourth spacer element disposed on the image side of the fourth lens and at least partially in contact with the image side surface of the fourth lens, and a seventh spacer element disposed on the image side of the seventh lens and at least partially in contact with the image side surface of the seventh lens; wherein the refractive index of the first lens among the first lens to the fourth lens is greater than the refractive index of the remaining three lenses; the effective focal length f1 of the first lens, the refractive index N1 of the first lens, the effective focal length f4 of the fourth lens and the refractive index N4 of the fourth lens satisfy f1 / N1 < -1.0 mm and 3.0 mm < |f4 / N4|; and the radius of curvature R1 of the object side surface of the first lens, the radius of curvature R2 of the image side surface of the first lens, the central thickness CT1 of the first lens on the optical axis, the air gap T12 of the first lens and the second lens on the optical axis, and the distance EP12 between the image side surface of the first spacer element and the object side surface of the second spacer element along the optical axis direction satisfy -15.0 < (R1+R2) / (CT1+T12+EP12) < -3.0. Since the refractive index of the first lens among the first four lenses is large, for a lens of high refractive index material, the light turning angle is too large, causing the first lens to be sensitive and the processing sensitivity to be high. By controlling the radius of curvature and the central thickness of the first lens, the spacing distance of the first lens and the second lens, and the parameter relationship between the first spacer element and the second spacer element, the assembly gap of the first lens and the second lens position lens can be controlled, the field curvature of the lens can be ensured within a certain range of variation, the sensitivity of the optical system of the lens can be reduced, and the assembly yield of the lens can be improved.

[0063] In an example embodiment, the optical imaging system according to the present application comprises: a lens barrel, and a plurality of lens elements and a plurality of spacer elements disposed in the lens barrel, wherein the plurality of lens elements comprises, in order from the object side to the image side along the optical axis, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens; and the plurality of spacer elements further comprises: a first spacer element disposed on the image side of the first lens and at least partially in contact with the image side surface of the first lens; a second spacer element disposed on the image side of the second lens and at least partially in contact with the image side surface of the second lens; and a third spacer element disposed on the image side of the third lens and at least partially in contact with the image side surface of the third lens; wherein the refractive index of the first lens among the first to fourth lenses is greater than the refractive index of the remaining three lenses; the curvature radius R2 of the image side surface of the first lens, the curvature radius R3 of the object side surface of the second lens, the curvature radius R4 of the image side surface of the second lens, the curvature radius R5 of the object side surface of the third lens, the outer diameter D1s of the object side surface of the first spacer element, the outer diameter D2s of the object side surface of the second spacer element, and the outer diameter D3s of the object side surface of the third spacer element satisfy: 40.0 < (R2+R3) / (D2s-D1s)+(R4+R5) / (D3s-D2s) < 50.0. Since the refractive index of the first lens among the first four lenses is relatively large, the light ray turning angle of the lens made of high refractive index material is prone to be too large, resulting in high sensitivity of the first lens and high processing sensitivity. By controlling the curvature radius of the image side surface of the first lens, the curvature radius of the object side surface of the second lens, the curvature radius of the image side surface of the second lens, the curvature radius of the object side surface of the third lens, and the outer diameter of the first spacer element, the second spacer element, and the third spacer element, the stray light and ghost images generated by the multiple reflections of the excess light rays outside the effective diameter of the first lens, the second lens, and the third lens in the effective diameter part and the non-effective diameter part of the lens structure can be avoided.

[0064] In an example embodiment, the first lens can have a negative refractive power, the second lens can have a positive refractive power, the third lens can have a positive refractive power, the fourth lens can have a positive refractive power or a negative refractive power, the fifth lens can have a positive refractive power or a negative refractive power, the sixth lens can have a negative refractive power, the seventh lens can have a positive refractive power, and the eighth lens can have a positive refractive power.

[0065] In the embodiments of the present application, at least one of the mirror surfaces of each lens is an aspherical mirror surface, i.e., at least one of the object side surface of the first lens to the image side surface of the eighth lens is an aspherical mirror surface. The aspherical lens is characterized in that the curvature is continuously changed from the center of the lens to the periphery of the lens. Unlike the spherical lens having a constant curvature from the center of the lens to the periphery of the lens, the aspherical lens has a better curvature radius characteristic, and has the advantages of improving the distortion aberration and improving the astigmatism aberration. After the aspherical lens is used, the aberration occurring during imaging can be eliminated as much as possible, thereby improving the imaging quality. Alternatively, the object side surface and the image side surface of all the lenses from the first lens to the eighth lens are aspherical mirror surfaces.

[0066] In the exemplary embodiments, the optical imaging system described above can further include a color filter for correcting color deviation and / or a protective glass for protecting the photosensitive element located on the imaging surface.

[0067] The optical imaging system according to the above embodiments of the present application can use multiple lenses, for example, eight lenses as described above. By reasonably allocating the optical power of each lens, the surface type, and the arrangement of each spacer element, etc., the span of each gear position of the lens and the lens barrel is relatively uniform, the light converging ability is enhanced, and the imaging quality of the ultra-thin large imaging surface imaging lens is improved. However, those skilled in the art should understand that the number of lenses constituting the optical imaging system can be changed without departing from the technical solutions claimed by the present application, to obtain the various results and advantages described in the specification. For example, although eight lenses are described in the embodiments, the optical imaging system is not limited to including eight lenses. If necessary, the optical imaging system can also include other numbers of lenses.

[0068] The specific embodiments of the optical imaging system applicable to the above embodiments are further described below with reference to the accompanying drawings.

[0069] Example 1

[0070] The following refers to Figures 2A to 3D The optical imaging system 1001, the optical imaging system 1002, and the optical imaging system 1003 according to Embodiment 1 of the present application are described. Figures 2A to 2C The structural schematic diagrams of the optical imaging system 1001, the optical imaging system 1002, and the optical imaging system 1003 according to Embodiment 1 of the present application are respectively shown.

[0071] As Figures 2A to 2C shown, the optical imaging system 1001, the optical imaging system 1002, and the optical imaging system 1003 each include a lens barrel P0, a lens group E1-E8, and a plurality of spacer elements P1-P8.

[0072] As Figures 2A to 2CAs shown, the optical imaging system 1001, the optical imaging system 1002 and the optical imaging system 1003 employ the same lens group, which comprises, in order from the object side to the image side: a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7 and an eighth lens E8. The first lens E1 has an object side surface S1 and an image side surface S2. The second lens E2 has an object side surface S3 and an image side surface S4. The third lens E3 has an object side surface S5 and an image side surface S6. The fourth lens E4 has an object side surface S7 and an image side surface S8. The fifth lens E5 has an object side surface S9 and an image side surface S10. The sixth lens E6 has an object side surface S11 and an image side surface S12. The seventh lens E7 has an object side surface S13 and an image side surface S14. The eighth lens E8 has an object side surface S15 and an image side surface S16. Light from an object passes through the surfaces S1 to S16 in order and is finally imaged on an imaging surface S17 (not shown).

[0073] Table 1 shows a table of basic parameters of the lens group of the optical imaging system 1001, the optical imaging system 1002 and the optical imaging system 1003 of Example 1, wherein the units of the radius of curvature, the thickness and the effective focal length are all millimeters (mm).

[0074]

[0075] Table 1

[0076] In Example 1, the object side surface and the image side surface of any one of the first lens E1 to the eighth lens E8 are aspherical surfaces, and the surface type x of each aspherical surface can be defined by, but not limited to, the following aspherical surface formula:

[0077]

[0078] wherein x is the sag of the aspherical surface at a height h along the optical axis, c is the paraxial curvature of the aspherical surface, c = 1 / R (i.e., the paraxial curvature c is the inverse of the radius of curvature R in Table 1 above), k is the conic coefficient, and Ai is the correction coefficient of the i-th order of the aspherical surface. Table 2 shows the high-order term coefficients A4, A6, A8, A10 and A12 that can be used for the aspherical surfaces S1-S16 in Example 1. 10 12 14 16 18 20 .

[0079]

[0080] Table 2

[0081] As Figures 2A to 2C ​​​​​As shown, the optical imaging system 1001, the optical imaging system 1002 and the optical imaging system 1003 each include at least 8 spacer elements, i.e. a first spacer element P1, a second spacer element P2, a third spacer element P3, a fourth spacer element P4, a fifth spacer element P5, a sixth spacer element P6, a seventh spacer element P7 and an eighth spacer element P8. The first spacer element P1 is disposed on the image side of the first lens and at least partially contacts the image side surface of the first lens; the second spacer element P2 is disposed on the image side of the second lens and at least partially contacts the image side surface of the second lens; the third spacer element P3 is disposed on the image side of the third lens and at least partially contacts the image side surface of the third lens; the fourth spacer element P4 is disposed on the image side of the fourth lens and at least partially contacts the image side surface of the fourth lens; the fifth spacer element P5 is disposed on the image side of the fifth lens and at least partially contacts the image side surface of the fifth lens; the sixth spacer element P6 is disposed on the image side of the sixth lens and at least partially contacts the image side surface of the sixth lens; the seventh spacer element P7 is disposed on the image side of the seventh lens and at least partially contacts the image side surface of the seventh lens; and the eighth spacer element P8 is disposed on the image side of the eighth lens and at least partially contacts the image side surface of the eighth lens.

[0082] As shown in FIG. 1A, the optical imaging system 1001 includes a first lens 101, a second lens 102, a third lens 103, a fourth lens 104, a fifth lens 105, a sixth lens 106, a seventh lens 107 and an eighth lens 108. Figure 2A As shown in FIG. 1A, the optical imaging system 1001 includes a first lens 101, a second lens 102, a third lens 103, a fourth lens 104, a fifth lens 105, a sixth lens 106, a seventh lens 107 and an eighth lens 108. Figure 2B As shown in FIG. 1A, the optical imaging system 1001 includes a first lens 101, a second lens 102, a third lens 103, a fourth lens 104, a fifth lens 105, a sixth lens 106, a seventh lens 107 and an eighth lens 108. Figure 2C As shown in FIG. 1A, the optical imaging system 1001 includes a first lens 101, a second lens 102, a third lens 103, a fourth lens 104, a fifth lens 105, a sixth lens 106, a seventh lens 107 and an eighth lens 108.

[0083] The above spacer elements can prevent external stray light from entering, make the lens and the lens barrel better abut, and enhance the structural stability of the optical imaging system 1001, the optical imaging system 1002 and the optical imaging system 1003.

[0084] Figure 3A The on-axis chromatic aberration curves of the optical imaging system 1001, the optical imaging system 1002 and the optical imaging system 1003 of Embodiment 1 are shown, which represent the deviation of light rays of different wavelengths from the converging focus point after passing through the lens. Figure 3B The astigmatism curves of the optical imaging system 1001, the optical imaging system 1002 and the optical imaging system 1003 of Embodiment 1 are shown, which represent the meridional image surface curvature and the sagittal image surface curvature. Figure 3C The distortion curves of the optical imaging system 1001, the optical imaging system 1002 and the optical imaging system 1003 of Embodiment 1 are shown, which represent the distortion size values corresponding to different image heights. Figure 3DThe magnification chromatic aberration curves of the optical imaging system 1001, the optical imaging system 1002 and the optical imaging system 1003 of Embodiment 1 are shown, which represent the deviation of the different image heights of light rays after passing through the lens. According to Figures 3A to 3D It can be seen that the optical imaging system 1001, the optical imaging system 1002 and the optical imaging system 1003 given by Embodiment 1 can achieve good imaging quality.

[0085] Example 2

[0086] The following refers to Figures 4A to 5D The optical imaging system 2001, the optical imaging system 2002 and the optical imaging system 2003 according to Embodiment 2 of the present application are described. In this embodiment and the following embodiments, for the sake of brevity, some similar descriptions as Embodiment 1 will be omitted. Figures 4A to 4C The structural schematic diagrams of the optical imaging system 2001, the optical imaging system 2002 and the optical imaging system 2003 according to Embodiment 2 of the present application are shown respectively.

[0087] As shown in Figures 4A to 4C , the optical imaging system 2001, the optical imaging system 2002 and the optical imaging system 2003 each include a lens barrel P0, lens groups E1-E8 and a plurality of spacer elements P1-P8.

[0088] As shown in Figures 4A to 4C , the optical imaging system 2001, the optical imaging system 2002 and the optical imaging system 2003 use the same lens group, which includes, in order from the object side to the image side, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7 and an eighth lens E8. The first lens E1 has an object side surface S1 and an image side surface S2. The second lens E2 has an object side surface S3 and an image side surface S4. The third lens E3 has an object side surface S5 and an image side surface S6. The fourth lens E4 has an object side surface S7 and an image side surface S8. The fifth lens E5 has an object side surface S9 and an image side surface S10. The sixth lens E6 has an object side surface S11 and an image side surface S12. The seventh lens E7 has an object side surface S13 and an image side surface S14. The eighth lens E8 has an object side surface S15 and an image side surface S16. Light from an object passes through each surface S1 to S16 in order and is finally imaged on an imaging surface S17 (not shown).

[0089] Table 3 shows a table of basic parameters of the lens groups of the optical imaging system 2001, the optical imaging system 2002, and the optical imaging system 2003 of Example 2, where the units of the radius of curvature, the thickness, and the effective focal length are millimeters (mm). Tables 4-1 and 4-2 show the high-order term coefficients that can be used for each aspherical mirror surface in Example 2, where each aspherical surface type can be defined by the formula (1) given in Example 1 above.

[0090]

[0091]

[0092] Table 3

[0093] Face Number A4 A6 A8 A10 A12 A14 A16 S1 1.0861E+00 -8.7487E-02 1.6985E-02 -3.0441E-03 7.6129E-04 -3.9784E-04 2.3039E-04 S2 7.5001E-01 -5.2333E-02 6.2620E-03 -1.6659E-03 2.3608E-04 -3.9352E-04 -6.8718E-05 S3 -1.2669E-01 4.3221E-03 -2.4286E-03 5.1312E-04 -2.1453E-04 4.9050E-05 -6.7600E-05 S4 -7.5167E-01 1.0562E-01 -1.7817E-02 3.5141E-03 -6.8062E-04 5.9211E-04 -1.2337E-04 S5 -7.9051E-01 6.6031E-02 -1.7416E-02 7.0362E-04 -1.1225E-03 -7.1255E-05 -1.4072E-04 S6 -4.5044E-01 5.5323E-02 3.1124E-03 -4.9626E-03 3.9583E-04 -1.0190E-03 -7.6913E-05 S7 -1.2689E-01 1.7922E-02 4.4376E-03 -6.0314E-04 4.8001E-05 -1.0366E-04 7.2700E-05 S8 -8.9356E-02 1.7758E-03 -3.0319E-03 3.7633E-03 -1.5639E-03 5.9406E-04 6.4296E-05 S9 -1.0505E+00 1.6096E-01 -5.0952E-03 -9.9526E-04 1.0796E-03 -2.9045E-04 -9.9346E-05 S10 -8.8904E-01 1.2729E-01 -6.8311E-03 -1.1915E-03 1.0200E-03 -1.2426E-03 -1.5292E-04 S11 8.0261E-01 -2.1880E-01 9.7251E-03 -6.0113E-03 2.4433E-03 -2.4870E-03 8.4520E-04 S12 1.9035E+00 -5.0617E-02 9.5796E-02 2.4779E-02 1.1470E-02 3.8590E-03 3.5140E-03 S13 -7.4513E-01 1.3268E-01 -1.5231E-02 1.2852E-02 7.8696E-04 2.2391E-03 -7.3113E-04 S14 -2.8638E-01 -7.1918E-02 3.6084E-03 4.2814E-03 4.9922E-03 8.8088E-04 -1.0496E-03 S15 -6.8994E-01 2.0369E-02 -2.8696E-02 -2.0631E-03 -7.7637E-05 -5.6134E-05 -1.9349E-04 S16 -1.9184E+00 1.9982E-01 -6.3507E-02 2.0191E-02 -4.3729E-03 9.2467E-04 -2.9211E-04

[0094] Table 4-1

[0095]

[0096]

[0097] Table 4-2

[0098] As Figures 4A to 4CAs shown, the optical imaging system 2001, the optical imaging system 2002 and the optical imaging system 2003 each comprises at least 8 spacer elements, i.e. a first spacer element P1, a second spacer element P2, a third spacer element P3, a fourth spacer element P4, a fifth spacer element P5, a sixth spacer element P6, a seventh spacer element P7 and an eighth spacer element P8. The first spacer element P1 is disposed on the image side of the first lens and at least partially contacts the image side surface of the first lens; the second spacer element P2 is disposed on the image side of the second lens and at least partially contacts the image side surface of the second lens; the third spacer element P3 is disposed on the image side of the third lens and at least partially contacts the image side surface of the third lens; the fourth spacer element P4 is disposed on the image side of the fourth lens and at least partially contacts the image side surface of the fourth lens; the fifth spacer element P5 is disposed on the image side of the fifth lens and at least partially contacts the image side surface of the fifth lens; the sixth spacer element P6 is disposed on the image side of the sixth lens and at least partially contacts the image side surface of the sixth lens; the seventh spacer element P7 is disposed on the image side of the seventh lens and at least partially contacts the image side surface of the seventh lens; the eighth spacer element P8 is disposed on the image side of the eighth lens and at least partially contacts the image side surface of the eighth lens. The optical imaging system 2001, the optical imaging system 2002 and the optical imaging system 2003 each further comprises a plurality of auxiliary spacer elements, such as a first auxiliary spacer element P1b, P1c and a second auxiliary spacer element P2b, P2c. The above spacer elements can block the external stray light from entering, make the lens better abut against the lens barrel, and enhance the structural stability of the optical imaging system 2001, the optical imaging system 2002 and the optical imaging system 2003.

[0099] Figure 5A The on-axis chromatic aberration curves of the optical imaging system 2001, the optical imaging system 2002 and the optical imaging system 2003 of Embodiment 2 are shown, which represent the deviation of light rays of different wavelengths from the convergent focal point after passing through the lens. Figure 5B The astigmatism curves of the optical imaging system 2001, the optical imaging system 2002 and the optical imaging system 2003 of Embodiment 2 are shown, which represent the meridional image surface curvature and the sagittal image surface curvature. Figure 5C The distortion curves of the optical imaging system 2001, the optical imaging system 2002 and the optical imaging system 2003 of Embodiment 2 are shown, which represent the distortion size values corresponding to different image heights. Figure 5D The magnification chromatic aberration curves of the optical imaging system 2001, the optical imaging system 2002 and the optical imaging system 2003 of Embodiment 2 are shown, which represent the deviation of light rays on the imaging surface at different image heights after passing through the lens. According to the magnification chromatic aberration curves, the optical imaging system 2001, the optical imaging system 2002 and the optical imaging system 2003 of Embodiment 2 have good imaging quality. Figures 5A to 5D It can be seen that the optical imaging system 2001, the optical imaging system 2002 and the optical imaging system 2003 given in Embodiment 2 can achieve good imaging quality.

[0100] Example 3

[0101] Reference will now be made to the drawings Figures 6A to 7D An optical imaging system 3001, an optical imaging system 3002 and an optical imaging system 3003 according to Embodiment 3 of the present application are described. Figures 6A to 6C Structural diagrams of the optical imaging system 3001, the optical imaging system 3002 and the optical imaging system 3003 according to Embodiment 3 of the present application are shown respectively.

[0102] As shown in Figures 6A to 6C , the optical imaging system 3001, the optical imaging system 3002 and the optical imaging system 3003 each include a lens barrel P0, lens groups E1-E8 and a plurality of spacer elements P1-P8 respectively.

[0103] As shown in Figures 6A to 6C , the optical imaging system 3001, the optical imaging system 3002 and the optical imaging system 3003 employ the same lens group, which includes, in order from the object side to the image side, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7 and an eighth lens E8. The first lens E1 has an object side surface S1 and an image side surface S2. The second lens E2 has an object side surface S3 and an image side surface S4. The third lens E3 has an object side surface S5 and an image side surface S6. The fourth lens E4 has an object side surface S7 and an image side surface S8. The fifth lens E5 has an object side surface S9 and an image side surface S10. The sixth lens E6 has an object side surface S11 and an image side surface S12. The seventh lens E7 has an object side surface S13 and an image side surface S14. The eighth lens E8 has an object side surface S15 and an image side surface S16. Light from an object passes through the surfaces S1 to S16 in order and is finally imaged on an imaging surface S17 (not shown).

[0104] Table 5 shows a table of basic parameters of the lens groups of the optical imaging system 3001, the optical imaging system 3002 and the optical imaging system 3003 of Embodiment 3, wherein the units of the radius of curvature, the thickness and the effective focal length are all millimeters (mm). Tables 6-1 and 6-2 show the high-order term coefficients of the aspherical surfaces that can be used in the optical imaging system 3001, the optical imaging system 3002 and the optical imaging system 3003 of Embodiment 3, wherein each aspherical surface type can be defined by the formula (1) given in Embodiment 1 above.

[0105]

[0106] Table 5

[0107]

[0108]

[0109] Table 6-1

[0110] Face Number A18 A20 A22 A24 A26 A28 A30 S1 -1.0113E-04 1.4731E-05 5.1369E-06 1.6775E-05 1.3259E-05 4.8481E-06 -1.6449E-06 S2 -3.1390E-05 -9.6366E-06 -1.8524E-05 -9.2551E-06 -5.8440E-06 6.7677E-06 1.7388E-06 S3 5.6815E-06 -5.6181E-06 -3.7927E-08 7.0379E-07 2.8820E-07 -1.9883E-08 -6.0949E-08 S4 -4.4696E-05 -8.6089E-05 -2.2452E-05 -3.2570E-05 -1.6057E-05 -4.2216E-06 -9.9348E-07 S5 4.7230E-05 6.6591E-05 4.1475E-05 -3.3190E-05 -4.8024E-05 -2.6253E-05 -7.7417E-06 S6 -7.4786E-05 1.2705E-04 6.5589E-05 -1.8351E-05 -5.2550E-05 -2.8047E-05 -1.0202E-05 S7 1.8809E-05 -4.0719E-06 -5.5145E-06 1.1931E-06 1.3060E-08 -6.4090E-07 -2.8528E-07 S8 -1.4799E-04 -5.8075E-05 6.3095E-05 5.6092E-05 1.3647E-05 -1.6460E-07 -2.1944E-07 S9 -9.3195E-05 -1.3053E-04 -1.0369E-06 -5.0560E-05 -4.3835E-05 -1.9785E-05 1.6199E-06 S10 -7.9543E-05 -5.5371E-05 6.3348E-05 1.6044E-05 8.5029E-07 -1.1555E-06 3.2999E-06 S11 -2.3769E-04 2.0650E-04 8.5850E-05 9.0269E-05 -4.9600E-06 6.0668E-06 -2.1042E-06 S12 3.6249E-04 9.2836E-04 -2.5140E-04 -7.3126E-05 -3.2568E-05 3.9114E-05 -3.8753E-05 S13 -7.7067E-05 1.1655E-04 -1.2436E-04 -1.5095E-04 -1.6945E-04 -5.7713E-05 -3.5005E-05 S14 -5.9814E-04 -1.5176E-04 4.6574E-05 5.0927E-05 -1.6957E-05 -1.8194E-05 -1.2321E-05 S15 -9.6818E-05 -3.7708E-05 1.0258E-05 1.9684E-05 1.4615E-05 9.0207E-06 1.4421E-06 S16 1.2892E-04 -5.7258E-06 -1.8526E-07 -1.2936E-08 0.0000E+00 0.0000E+00 0.0000E+00

[0111] Table 6-2

[0112] As shown in Figures 6A to 6C Figure 6-1, the optical imaging system 3001, the optical imaging system 3002 and the optical imaging system 3003 each include at least eight spacer elements, i.e., a first spacer element P1, a second spacer element P2, a third spacer element P3, a fourth spacer element P4, a fifth spacer element P5, a sixth spacer element P6, a seventh spacer element P7 and an eighth spacer element P8. The first spacer element P1 is disposed on the image side of the first lens and at least partially contacts the image side surface of the first lens; the second spacer element P2 is disposed on the image side of the second lens and at least partially contacts the image side surface of the second lens; the third spacer element P3 is disposed on the image side of the third lens and at least partially contacts the image side surface of the third lens; the fourth spacer element P4 is disposed on the image side of the fourth lens and at least partially contacts the image side surface of the fourth lens; the fifth spacer element P5 is disposed on the image side of the fifth lens and at least partially contacts the image side surface of the fifth lens; the sixth spacer element P6 is disposed on the image side of the sixth lens and at least partially contacts the image side surface of the sixth lens; the seventh spacer element P7 is disposed on the image side of the seventh lens and at least partially contacts the image side surface of the seventh lens; and the eighth spacer element P8 is disposed on the image side of the eighth lens and at least partially contacts the image side surface of the eighth lens. The optical imaging system 3001, the optical imaging system 3002 and the optical imaging system 3003 each further include a plurality of auxiliary spacer elements, such as a first auxiliary spacer element P1b, P1c and a second auxiliary spacer element P2b, P2c. The above spacer elements can block the entry of external stray light, make the lens better abut the lens barrel, and enhance the structural stability of the optical imaging system 3001, the optical imaging system 3002 and the optical imaging system 3003.

[0113] Figure 7A Figure 6-3 shows the on-axis chromatic aberration curves of the optical imaging system 3001, the optical imaging system 3002 and the optical imaging system 3003 of Example 3, which represent the deviation of light rays of different wavelengths from the converging focal point after passing through the lens. Figure 7B Figure 6-4 shows the astigmatism curves of the optical imaging system 3001, the optical imaging system 3002 and the optical imaging system 3003 of Example 3, which represent the meridional image surface curvature and the sagittal image surface curvature. Figure 7C Figure 6-5 shows the distortion curves of the optical imaging system 3001, the optical imaging system 3002 and the optical imaging system 3003 of Example 3, which represent the distortion size values corresponding to different image heights. Figure 7D Figure 6-6 shows the lateral chromatic aberration curves of the optical imaging system 3001, the optical imaging system 3002 and the optical imaging system 3003 of Example 3, which represent the deviation of light rays on the imaging surface at different image heights after passing through the lens. According to Figures 7A to 7DIt can be seen that the optical imaging systems 3001, 3002 and 3003 given in Embodiment 3 can achieve good imaging quality.

[0114] Table 7 shows the basic parameters of the lens groups, spacer elements and lens barrels of the optical imaging systems 1001, 1002, 1003, 2001, 2002, 2003, 3001, 3002 and 3003 of Embodiments 1 to 3.

[0115]

[0116]

[0117] Table 7

[0118] In summary, the optical imaging systems 1001, 1002, 1003, 2001, 2002, 2003, 3001, 3002 and 3003 of Embodiments 1 to 3 satisfy the relationships shown in Table 8.

[0119]

[0120]

[0121] Table 8

[0122] 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 device (CMOS). The imaging device can be a stand-alone imaging apparatus 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 system described above.

[0123] The above description is merely preferred embodiments of the present application and a description of the principles of the technology used. It should be understood by those skilled in the art that the scope of the application involved in the present application is not limited to the technical solutions formed by the specific combinations of the technical features described above, and should also cover other technical solutions formed by any combinations of the technical features described above or their equivalent features without departing from the inventive concept. For example, the technical solutions formed by the mutual replacement of the above-described features and the technical features disclosed in the present application (but not limited to) having similar functions.

Claims

1. An optical imaging system characterized by, The optical imaging system comprises: a lens barrel, a lens group and a plurality of spacer elements disposed in the lens barrel, wherein the lens group comprises, in order from the object side to the image side along the optical axis, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens and an eighth lens; and the plurality of spacer elements comprises a fourth spacer element disposed on the image side of the fourth lens and at least partially in contact with the image side surface of the fourth lens, a seventh spacer element disposed on the image side of the seventh lens and at least partially in contact with the image side surface of the seventh lens, and an eighth spacer element disposed on the image side of the eighth lens and at least partially in contact with the image side surface of the eighth lens; wherein the refractive index of the first lens among the first lens to the fourth lens is greater than the refractive index of the remaining three lenses; the effective focal length f4 of the fourth lens, the radius of curvature R8 of the image side surface of the fourth lens, the effective focal length f8 of the eighth lens, the radius of curvature R15 of the object side surface of the eighth lens, and the outer diameter D4s of the object side surface of the fourth spacer element and the outer diameter D7s of the object side surface of the seventh spacer element satisfy: 0.43≤(f4 / R8+f8 / R15)×(D7s / D4s)≤2.18; and the effective focal length f1 of the first lens, the radius of curvature R1 of the object side surface of the first lens, the effective focal length f4 of the fourth lens, the radius of curvature R8 of the image side surface of the fourth lens, the outer diameter D4s of the object side surface of the fourth spacer element and the inner diameter d4s of the object side surface of the fourth spacer element satisfy: 4.53≤(f1 / R1+f4 / R8)×(D4s / d4s)≤7.40; the radius of curvature R15 of the object side surface of the eighth lens, the radius of curvature R16 of the image side surface of the eighth lens, the maximum outer diameter D8max of the eighth spacer element and the minimum inner diameter d8min of the eighth spacer element satisfy: -27.82≤(R15-R16) / (D8max-d8min)≤-19.67; the first lens has a negative focal power, the object side surface thereof is concave, and the image side surface thereof is convex; the second lens has a positive focal power, the object side surface thereof is convex, and the image side surface thereof is concave; the third lens has a positive focal power, the object side surface thereof is convex, and the image side surface thereof is concave; the object side surface of the fifth lens is convex, and the image side surface thereof is concave; the sixth lens has a negative focal power, the object side surface thereof is concave, and the image side surface thereof is convex; the seventh lens has a positive focal power, the object side surface thereof is convex, and the image side surface thereof is convex; the eighth lens has a negative focal power, the object side surface thereof is concave, and the image side surface thereof is concave; the fourth lens and the fifth lens have opposite positive and negative properties of focal power; the number of lenses with focal power in the optical imaging system is eight.

2. The optical imaging system of claim 1, wherein, The plurality of spacer elements further comprises: a first spacer element disposed on the image side of the first lens and at least partially in contact with the image side surface of the first lens; a second spacer element disposed on the image side of the second lens and at least partially in contact with the image side surface of the second lens; wherein The effective focal length f1 of the first lens, the effective focal length f2 of the second lens, the inner diameter d1m of the image side surface of the first spacer element, the inner diameter d2m of the image side surface of the second spacer element, the dispersion coefficient V1 of the first lens, and the dispersion coefficient V2 of the second lens satisfy: 8.16≤(V2-V1) / (f1 / d1m+f2 / d2m)≤16.

66.

3. The optical imaging system of claim 1, wherein, The plurality of spacer elements further comprises: a first spacer element disposed on the image side of the first lens and at least partially in contact with the image side surface of the first lens; a second spacer element disposed on the image side of the second lens and at least partially in contact with the image side surface of the second lens; wherein The radius of curvature R1 of the object side surface of the first lens, the radius of curvature R2 of the image side surface of the first lens, the central thickness CT1 of the first lens on the optical axis, the air gap T12 of the first lens and the second lens on the optical axis, and the distance EP12 of the image side surface of the first spacer element and the object side surface of the second spacer element along the direction of the optical axis satisfy: -10.54≤(R1+R2) / (CT1+T12+EP12)≤-6.

65.

4. The optical imaging system of claim 1, wherein, The plurality of spacer elements further comprises: a first spacer element disposed on the image side of the first lens and at least partially in contact with the image side surface of the first lens; a second spacer element disposed on the image side of the second lens and at least partially in contact with the image side surface of the second lens; and a third spacer element disposed on the image side of the third lens and at least partially in contact with the image side surface of the third lens; wherein The radius of curvature R2 of the image side surface of the first lens, the radius of curvature R3 of the object side surface of the second lens, the radius of curvature R4 of the image side surface of the second lens, the radius of curvature R5 of the object side surface of the third lens, the outer diameter D1s of the object side surface of the first spacer element, the outer diameter D2s of the object side surface of the second spacer element, and the outer diameter D3s of the object side surface of the third spacer element satisfy: 43.23≤(R2+R3) / (D2s-D1s)+(R4+R5) / (D3s-D2s)≤46.

97.

5. The optical imaging system of claim 1, wherein, The plurality of spacer elements further comprises: a first spacer element disposed on the image side of the first lens and at least partially in contact with the image side surface of the first lens; wherein The central thickness CT1 of the first lens on the optical axis, the effective focal length f1 of the first lens, the distance EP01 of the object side end surface of the lens barrel to the object side surface of the first spacer element along the direction of the optical axis, the inner diameter d0s of the object side end surface of the lens barrel, and the inner diameter d1s of the object side surface of the first spacer element satisfy: 1.38≤|(EP01-CT1)×f1| / [(d0s-d1s)×f]≤4.

42.

6. The optical imaging system of claim 1, wherein, The plurality of spacer elements further comprises: a fifth spacer element disposed on the image side of the fifth lens and at least partially in contact with the image side surface of the fifth lens; wherein A radius of curvature R8 of an image side surface of the fourth lens, a radius of curvature R9 of an object side surface of the fifth lens, a central thickness CT4 of the fourth lens on the optical axis, a central thickness CT5 of the fifth lens on the optical axis, an air separation T45 of the fourth lens and the fifth lens on the optical axis, an outer diameter D4s of an object side surface of the fourth spacer element, and an outer diameter D5s of an object side surface of the fifth spacer element satisfy: -4.28≤(R9 / D5s-R8 / D4s)×T45 / (CT4+CT5)≤2.

78.

7. The optical imaging system of claim 1, wherein, The plurality of spacer elements further comprises: a second spacer element disposed on an image side of the second lens and at least partially in contact with an image side surface of the second lens; a third spacer element disposed on an image side of the third lens and at least partially in contact with an image side surface of the third lens; wherein an effective focal length f2 of the second lens, an effective focal length f3 of the third lens, a refractive index N2 of the second lens, a refractive index N3 of the third lens, an inner diameter d2s of an object side surface of the second spacer element, and an inner diameter d3s of an object side surface of the third spacer element satisfy: 11.25≤(f2+f3)×(N2+N3) / (d2s+d3s)≤16.

36.

8. The optical imaging system of claim 1, wherein, The plurality of spacer elements further comprises: a fifth spacer element disposed on an image side of the fifth lens and at least partially in contact with an image side surface of the fifth lens; a sixth spacer element disposed on an image side of the sixth lens and at least partially in contact with an image side surface of the sixth lens; wherein an image side surface inner diameter d5m of the fifth spacer element, an object side surface inner diameter d6s of the sixth spacer element, a radius of curvature R10 of an image side surface of the fifth lens, a radius of curvature R11 of an object side surface of the sixth lens, a dispersion coefficient V5 of the fifth lens, and a dispersion coefficient V6 of the sixth lens satisfy: 30.01≤(d5m+d6s) / (R10 / V5+R11 / V6)≤63.

92.

9. The optical imaging system of claim 1, wherein, The plurality of spacer elements further comprises: a second spacer element disposed on an image side of the second lens and at least partially in contact with an image side surface of the second lens; a third spacer element disposed on an image side of the third lens and at least partially in contact with an image side surface of the third lens; wherein a combined focal length f12 of the first lens and the second lens, a combined focal length f34 of the third lens and the fourth lens, a distance EP23 of an image side surface of the second spacer element and an object side surface of the third spacer element along the optical axis direction, a maximum thickness CP2 of the second spacer element along the optical axis direction, and a maximum thickness CP3 of the third spacer element along the optical axis direction satisfy: -24.84≤(f12+f34) / (EP23+CP2+CP3)≤-19.

34.

10. The optical imaging system of claim 1, wherein, The plurality of spacer elements further comprises: a sixth spacer element disposed on an image side of the sixth lens and at least partially in contact with an image side surface of the sixth lens; an eighth spacer element disposed on an image side of the eighth lens and at least partially in contact with an image side surface of the eighth lens; wherein an image side surface inner diameter d6m of the sixth spacer element, an object side surface inner diameter d8s of the eighth spacer element, a radius of curvature R12 of an image side surface of the sixth lens, a radius of curvature R13 of an object side surface of the eighth lens, a dispersion coefficient V6 of the sixth lens, and a dispersion coefficient V8 of the eighth lens satisfy: An inner diameter d6m of an image-side surface of the sixth spacer element, an inner diameter d7m of an image-side surface of the seventh spacer element, an inner diameter d8m of an image-side surface of the eighth spacer element, an effective focal length f6 of the sixth lens, an effective focal length f7 of the seventh lens, and an effective focal length f8 of the eighth lens satisfy: 3.61 ≤ d6m / |f6| + d7m / |f7| + d8m / |f8| ≤ 4.

12.

11. The optical imaging system of claim 1, wherein, The plurality of spacer elements further include: a sixth spacer element disposed on an image side of the sixth lens and at least partially in contact with an image-side surface of the sixth lens; wherein, A radius of curvature R12 of an image-side surface of the sixth lens, a radius of curvature R13 of an object-side surface of the seventh lens, a central thickness CT6 of the sixth lens on the optical axis, 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 maximum thickness CP6 of the sixth spacer element along the direction of the optical axis satisfy: -35.80 ≤ (R12-R13) x T67 / [(D6m-d6m) x CP6] ≤ -15.

46.

12. The optical imaging system of any of claims 1-5, wherein, The plurality of spacer elements further include: a fifth spacer element disposed on an image side of the fifth lens and at least partially in contact with an image-side surface of the fifth lens; wherein, An inner diameter d4m of an image-side surface of the fourth spacer element, an outer diameter D4m of the image-side surface of the fourth spacer element, an inner diameter d5s of an object-side surface of the fifth spacer element, an outer diameter D5s of the object-side surface of the fifth spacer element, a radius of curvature R9 of an object-side surface of the fifth lens, and a radius of curvature R10 of an image-side surface of the fifth lens satisfy: -17.84 ≤ (D5s-d5s) x R10 - (D4m-d4m) x R9 ≤ 29.

86.

13. The optical imaging system of any of claims 1-11, wherein, An effective focal length f1 of the first lens, a refractive index N1 of the first lens, an effective focal length f4 of the fourth lens, and a refractive index N4 of the fourth lens satisfy: -11.38 mm ≤ f1 / N1 ≤ -9.73 mm and 5.79 mm ≤ |f4 / N4| ≤ 20.43 mm.

14. The optical imaging system of any of claims 1, 6-11, wherein, The plurality of spacer elements further include: a first spacer element disposed on an image side of the first lens and at least partially in contact with an image-side surface of the first lens; wherein, A maximum effective radius DT11 of an object-side surface of the first lens, a maximum effective radius DT12 of an image-side surface of the first lens, an inner diameter d1s of an object-side surface of the first spacer element, and an inner diameter d1m of an image-side surface of the first spacer element satisfy: 3.88 ≤ (DT11-DT12) / (d1s-d1m) ≤ 10.

59.

15. The optical imaging system of any of claims 1-11, wherein, A minimum inner diameter d0min of a front end portion of the lens barrel facing the object side and a maximum field of view FOV of the optical imaging system satisfy: 6.57 mm ≤ d0min / tan(FOV / 2) ≤ 6.72 mm.

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