Optical imaging system

Abstract

The present application discloses an optical imaging system, which includes a lens barrel and a five-lens group and a spacer element group disposed in the lens barrel, wherein the five-lens group includes a first lens, a second lens, a third lens, a fourth lens, and a fifth lens arranged in sequence along the optical axis from the object side to the image side, wherein the fifth lens has negative refractive power; the spacer element group includes a fourth spacer element and a fifth spacer element, wherein the fourth spacer element is disposed on the image side surface of the fourth lens and contacts the image side surface of the fourth lens, and the fifth spacer element is disposed on the image side surface of the fifth lens and contacts the image side surface of the fifth lens; wherein the effective focal length f5 of the fifth lens, the center thickness CT5 of the fifth lens on the optical axis, the air gap T45 between the fourth lens and the fifth lens on the optical axis, and the gap EP45 between the fourth spacer element and the fifth spacer element along the optical axis satisfy the following conditions: -25.0<(EP45 / CT5)×(f5 / T45)<-5.0.

Description

Technical Field

[0001] The present application relates to the field of optical devices, and in particular to a five-element optical imaging system. Background Art

[0002] As the requirements for mobile phone photography increase, the requirements for the optical imaging system, the core component of mobile phone photography, also increase. For example, while improving the shooting performance of the optical imaging system, it is necessary to ensure the assembly stability of the optical imaging system.

[0003] The last lens of a five-element optical imaging system is relatively sensitive. In the actual design process, in order to meet the imaging quality of the five-element optical imaging system, the rationality of the lens and the spacer elements at the position of the lens are often ignored, which will make the assembly stability of the optical imaging system worse and seriously affect the assembly yield of the optical imaging system. Summary of the Invention

[0004] The present application provides an optical imaging system that can at least solve or partially solve at least one problem or other problems existing in the prior art.

[0005] One aspect of the present application provides an optical imaging system, which includes a lens barrel and a five-lens group and a spacer element group disposed in the lens barrel, wherein the five-lens group includes a first lens, a second lens, a third lens, a fourth lens, and a fifth lens arranged in sequence along the optical axis from the object side to the image side, wherein the fifth lens has negative refractive power; the spacer element group includes a fourth spacer element and a fifth spacer element, the fourth spacer element is disposed on the image side surface of the fourth lens and contacts the image side surface of the fourth lens, and the fifth spacer element is disposed on the image side surface of the fifth lens and contacts the image side surface of the fifth lens; wherein the effective focal length f5 of the fifth lens, the center thickness CT5 of the fifth lens on the optical axis, the air gap T45 between the fourth lens and the fifth lens on the optical axis, and the gap EP45 between the fourth spacer element and the fifth spacer element along the optical axis satisfy the following conditions: -25.0<(EP45 / CT5)×(f5 / T45)<-5.0.

[0006] According to an exemplary embodiment of the present application, the spacer element group further includes a third spacer element disposed on the image side of the third lens and in contact with the image side of the third lens, wherein the effective focal length f4 of the fourth lens, the air gap T34 between the third lens and the fourth lens on the optical axis, and the maximum thickness CP3 of the third spacer element satisfy: 5.0 <f4 / (T34-CP3)<25.0。

[0007] According to an exemplary embodiment of the present application, the spacer element group further includes a second spacer element and a third spacer element, the second spacer element is placed on the image side surface of the second lens and contacts the image side surface of the second lens, and the third spacer element is placed on the image side surface of the third lens and contacts the image side surface of the third lens, wherein the curvature radius R5 of the object side surface of the third lens, the curvature radius R6 of the image side surface of the third lens, the outer diameter D2m of the image side surface of the second spacer element, and the outer diameter D3s of the object side surface of the third spacer element satisfy: |D2m / R5+D3s / R6|<1.5.

[0008] According to an exemplary embodiment of the present application, the spacer element group further includes a third spacer element disposed on the image side surface of the third lens and in contact with the image side surface of the third lens, wherein the curvature radius R8 of the image side surface of the fourth lens, the maximum thickness CP3 of the third spacer element, and the interval EP34 between the third spacer element and the fourth spacer element along the optical axis satisfy: -11.0≤R8 / (EP34+CP3)<-2.0.

[0009] According to an exemplary embodiment of the present application, the effective focal length f4 of the fourth lens, the center thickness CT4 of the fourth lens on the optical axis, the air gap T45 between the fourth lens and the fifth lens on the optical axis, and the maximum thickness CP4 of the fourth spacer element satisfy: 3.0 <f4 / (CT4+T45-CP4)<7.5。

[0010] According to an exemplary embodiment of the present application, the spacer element group further includes a first spacer element and a second spacer element, the first spacer element is placed on the image side surface of the first lens and contacts the image side surface of the first lens, and the second spacer element is placed on the image side surface of the second lens and contacts the image side surface of the second lens, wherein the effective focal length f2 of the second lens, the inner diameter d1m of the image side surface of the first spacer element and the inner diameter d2s of the object side surface of the second spacer element satisfy: 20<(f2 / d1m)×(f2 / d2s)≤50.

[0011] According to an exemplary embodiment of the present application, the effective focal length f2 of the second lens, the refractive index N2 of the second lens, and the interval EP12 between the first and second spacing elements along the optical axis satisfy: 10<|f2 / N2| / EP12≤21.

[0012] According to an exemplary embodiment of the present application, the spacer element group further includes a first spacer element disposed on the image side surface of the first lens and in contact with the image side surface of the first lens, wherein the total effective focal length f of the optical imaging system, the outer 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: 0.5 <f / (D0s-d1s)≤1.5。

[0013] According to an exemplary embodiment of the present application, the outer diameter D0s of the object-side end face of the lens barrel, the inner diameter d0s of the object-side end face of the lens barrel, the distance EP01 between the object-side end face of the lens barrel and the first spacer element along the optical axis, and half of the maximum field angle Semi-FOV of the optical imaging system satisfy: 2.5 < (D0s - d0s) / (EP01 × tan(Semi-FOV)) < 6.0.

[0014] According to an exemplary embodiment of the present application, the outer diameter D0m of the image-side end face of the lens barrel, the inner diameter d1s of the object-side face of the first spacer element, the length L of the lens barrel in the direction of the optical axis, and the distance EP01 between the object-side end face of the lens barrel and the first spacer element along the optical axis satisfy: 1.5 < (D0m - d1s) / (L - EP01) < 2.5.

[0015] According to an exemplary embodiment of the present application, the effective focal length f5 of the fifth lens, the inner diameter d4s of the object-side face of the fourth spacer element, and the inner diameter d5s of the object-side face of the fifth spacer element satisfy: -2.0 < f5 / (d5s - d4s) ≤ -1.0.

[0016] According to an exemplary embodiment of the present application, the spacer element group further includes a first spacer element and a third spacer element. The first spacer element is placed on the image-side face of the first lens and contacts the image-side face of the first lens. The third spacer element is placed on the image-side face of the third lens and contacts the image-side face of the third lens. Among them, the optical imaging system further satisfies: 5.0 < dis / ((Ni - 1) × CTi) < 55.0, where i = 1, 3, 4, or 5. When i = 1, Ni represents the refractive index of the first lens, CTi represents the central thickness of the first lens on the optical axis, and dis represents the inner diameter of the object-side face of the first spacer element; when i = 3, Ni represents the refractive index of the third lens, CTi represents the central thickness of the third lens on the optical axis, and dis represents the inner diameter of the object-side face of the third spacer element; when i = 4, Ni represents the refractive index of the fourth lens, CTi represents the central thickness of the fourth lens on the optical axis, and dis represents the inner diameter of the object-side face of the fourth spacer element; when i = 5, Ni represents the refractive index of the fifth lens, CTi represents the central thickness of the fifth lens on the optical axis, and dis represents the inner diameter of the object-side face of the fifth spacer element.

[0017] According to an exemplary embodiment of the present application, the second lens has a negative refractive power, and the absolute value of the effective focal length of the second lens is greater than the absolute value of the effective focal length of the fifth lens.

[0018] According to an exemplary embodiment of the present application, the first lens and the fourth lens have a positive refractive power, and the image-side face of the fourth lens is convex at the paraxial region.

[0019] According to an exemplary embodiment of the present application, outer diameters of the first lens and the second lens are smaller than an outer diameter of the object-side end surface of the lens barrel.

[0020] While limiting the effective focal length and center thickness of the fifth lens, the present application constrains the spacing between the fourth spacer element and the fifth spacer element along the optical axis within a certain range, thereby maximizing the adjustment of the field of view peak and the field curvature of the outer field of view, ensuring that the optical imaging system has good coma performance, and effectively adjusting the aberration of the front-end optical lens of the optical imaging system. On the premise of ensuring that the optical imaging system meets the aberration design, the assembly stability and assembly yield of the optical imaging system are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Other features, objects and advantages of the present application will become more apparent upon reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0022] Figure 1 shows a parameter diagram of an optical imaging system according to the present application;

[0023] Figure 2 A schematic structural diagram of a five-lens lens assembly of an optical imaging system according to a first embodiment of the present application is shown;

[0024] Figure 3 shows an overall schematic diagram of an optical imaging system according to Example 1 of the first embodiment of the present application;

[0025] Figure 4 shows an overall schematic diagram of an optical imaging system according to Example 2 of the first embodiment of the present application;

[0026] Figure 5 shows an overall schematic diagram of an optical imaging system according to Example 3 of the first embodiment of the present application;

[0027] 6A to 6D axial chromatic aberration curve, astigmatism curve, distortion curve, and magnification chromatic aberration curve of the optical imaging system according to the first embodiment of the present application are respectively shown;

[0028] Figure 7 A schematic structural diagram of a five-lens lens assembly of an optical imaging system according to a second embodiment of the present application is shown;

[0029] Figure 8 shows an overall schematic diagram of an optical imaging system according to Example 1 of the second embodiment of the present application;

[0030] Figure 9 FIG2 shows an overall schematic diagram of an optical imaging system according to Example 2 of the second embodiment of the present application;

[0031] Figure 10 shows an overall schematic diagram of an optical imaging system according to Example 3 of the second embodiment of the present application;

[0032] 11A to 11D axial chromatic aberration curve, astigmatism curve, distortion curve, and magnification chromatic aberration curve of the optical imaging system according to the second embodiment of the present application are respectively shown;

[0033] Figure 12 A schematic structural diagram of a five-lens lens assembly of an optical imaging system according to a third embodiment of the present application is shown;

[0034] Figure 13 shows an overall schematic diagram of an optical imaging system according to Example 1 of the third embodiment of the present application;

[0035] Figure 14 shows an overall schematic diagram of an optical imaging system according to Example 2 of the third embodiment of the present application;

[0036] Figure 15 FIG2 shows an overall schematic diagram of an optical imaging system according to Example 3 of the third embodiment of the present application;

[0037] 16A to 16D axial chromatic aberration curve, astigmatism curve, distortion curve, and magnification chromatic aberration curve of the optical imaging system according to the second embodiment of the present application are respectively shown;

[0038] Figure 17 A schematic structural diagram of a five-lens lens assembly of an optical imaging system according to a fourth embodiment of the present application is shown;

[0039] Figure 18 shows an overall schematic diagram of an optical imaging system according to Example 1 of the fourth embodiment of the present application;

[0040] Figure 19 shows an overall schematic diagram of an optical imaging system according to Example 2 of the fourth embodiment of the present application;

[0041] Figure 20 shows an overall schematic diagram of an optical imaging system according to Example 3 of the fourth embodiment of the present application; and

[0042] 21A to 21D The axial chromatic aberration curve, astigmatism curve, distortion curve and magnification chromatic aberration curve of the optical imaging system according to the fourth embodiment of the present application are respectively shown. DETAILED DESCRIPTION

[0043] In order to better understand the present application, various aspects of the present application will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed descriptions are merely descriptions of exemplary embodiments of the present application and are not intended to limit the scope of the present application in any way. Throughout the specification, the same reference numerals refer to the same elements.

[0044] It should be noted that, in this specification, the expressions first, second, third, etc. are only used to distinguish one feature from another feature, and do not mean any limitation to the features.

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

[0046] In this document, the paraxial region refers to the area near the optical axis. If a lens surface is convex and the location of the convex surface is undefined, it means that the lens surface is convex at least in the paraxial region. If a lens surface is concave and the location of the concave surface is undefined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the object side is called the object side surface of the lens, and the surface of each lens closest to the image side is called the image side surface of the lens.

[0047] It should also be understood that the terms “comprises,” “including,” “having,” “includes,” and / or “comprising,” when used in this specification, indicate 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 combinations thereof.

[0048] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by those skilled 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 consistent with their meaning in the context of the relevant technology and will not be interpreted in an idealized or overly formal sense unless expressly defined as such herein.

[0049] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0050] like Figures 2 to 5 、 Figures 7 to 10 、 Figures 12 to 15 as well as Figures 17 to 20As shown, an optical imaging system according to an exemplary embodiment of the present application may include a lens barrel and a five-lens lens assembly disposed within the lens barrel. The lens barrel has an object-side end surface, an image-side end surface, an outer annular surface, and an inner annular surface. The five-lens lens assembly may include a first lens, a second lens, a third lens, a fourth lens, and a fifth lens arranged in order from the object side to the image side along the optical axis, wherein the fifth lens has a negative refractive power. Any two adjacent lenses of the first through fifth lenses may have an air space between them.

[0051] The optical imaging system may further include a spacer element group disposed within the lens barrel. The spacer element group may include a fourth spacer element and a fifth spacer element. The fourth spacer element is disposed on the image side of the fourth lens element and contacts the image side of the fourth lens element. The fifth spacer element is disposed on the image side of the fifth lens element and contacts the image side of the fifth lens element. The effective focal length f5 of the fifth lens element, the center thickness CT5 of the fifth lens element on the optical axis, the air gap T45 between the fourth and fifth lenses on the optical axis, and the spacing EP45 between the fourth and fifth spacer elements along the optical axis may satisfy the following conditions: -25.0 < (EP45 / CT5) × (f5 / T45) < -5.0. While limiting the effective focal length and center thickness of the fifth lens element, the present application constrains the spacing between the fourth and fifth spacer elements along the optical axis within a certain range, maximizing adjustment of the peak field of view and field curvature of the external field of view, ensuring good coma performance of the optical imaging system, and effectively adjusting the aberrations of the front optical lens of the optical imaging system. While ensuring that the optical imaging system meets the aberration design, the assembly stability and assembly yield of the optical imaging system are improved.

[0052] In other examples, the spacer element group may further include a first spacer element, a second spacer element, and a third spacer element. The first spacer element is positioned on the image side of the first lens and in contact with the image side of the first lens, the second spacer element is positioned on the image side of the second lens and in contact with the image side of the second lens, and the third spacer element is positioned on the image side of the third lens and in contact with the image side of the third lens. Proper use of spacer elements can effectively mitigate stray light risks, reduce interference with image quality, and thereby improve the imaging quality of the optical imaging system.

[0053] In an exemplary embodiment, the second lens has a negative refractive power, and the absolute value of the effective focal length of the second lens is greater than the absolute value of the effective focal length of the fifth lens. By setting the refractive power of the second lens to a negative value and the absolute value of the effective focal length of the second lens to a larger value, the total effective focal length of the optical imaging system can be lengthened.

[0054] In an exemplary embodiment, the first lens and the fourth lens have positive refractive powers, and the image side surface of the fourth lens is convex at the paraxial region. By making the refractive powers of the first lens and the fourth lens positive, light rays with smaller incident angles can enter each lens, thereby reducing the aberration of the optical imaging system.

[0055] In an exemplary embodiment, the outer diameters of the first lens and the second lens are smaller than the outer diameter of the object-side end face of the lens barrel. By making the first lens and the second lens have smaller outer diameters, the assembly stability of the first lens and the second lens in the lens barrel can be improved, and the assembly sensitivity of the first lens and the second lens can be reduced.

[0056] In an exemplary embodiment, the effective focal length f4 of the fourth lens, the air gap T34 between the third lens and the fourth lens on the optical axis, and the maximum thickness CP3 of the third spacer element can satisfy: 5.0 < f4 / (T34 - CP3) < 25.0. By restricting the effective focal length of the fourth lens within a certain range and constraining the air gap between the third lens and the fourth lens on the optical axis and the maximum thickness of the third spacer element, the aberration of the front-end optical lens of the optical imaging system can be effectively controlled, so that the aberration of the optical imaging system meets the design requirements, and the optical imaging system shows a good state in terms of structural and assembly stability.

[0057] In an exemplary embodiment, the curvature radius R5 of the object side surface of the third lens, the curvature radius R6 of the image side surface of the third lens, the outer diameter D2m of the image side surface of the second spacer element, and the outer diameter D3s of the object side surface of the third spacer element can satisfy: |D2m / R5 + D3s / R6| < 1.5. By restricting the curvature radii of the object side surface and the image side surface of the third lens within a certain range and constraining the outer diameter of the image side surface of the second spacer element and the outer diameter of the object side surface of the third spacer element, it is beneficial to control the imaging quality of light rays when passing through the third lens, make the light ray angle of the field of view within a reasonable range, and effectively reduce the sensitivity of the optical imaging system.

[0058] In an exemplary embodiment, the curvature radius R8 of the image side surface of the fourth lens, the maximum thickness CP3 of the third spacer element, and the gap EP34 between the third spacer element and the fourth spacer element along the optical axis can satisfy: -11.0 ≤ R8 / (EP34 + CP3) < -2.0. By controlling the mutual relationship between the curvature radius of the image side surface of the fourth lens, the maximum thickness of the third spacer element, and the gap between the third spacer element and the fourth spacer element along the optical axis, the deflection angle of the outer field of view surface can be restricted, and the fault tolerance distance of the optical imaging system can be increased within a certain range, reducing the sensitivity of the optical imaging system.

[0059] In an exemplary embodiment, the effective focal length f4 of the fourth lens, the central thickness CT4 of the fourth lens on the optical axis, the air gap T45 between the fourth lens and the fifth lens on the optical axis, and the maximum thickness CP4 of the fourth spacer element may satisfy: 3.0 < f4 / (CT4 + T45 - CP4) < 7.5. By restricting the effective focal length of the fourth lens within a certain range while constraining the central thickness of the fourth lens on the optical axis, the air gap between the fourth lens and the fifth lens on the optical axis, and the maximum thickness of the fourth spacer element, the aberration of the front optical lenses of the optical imaging system can be effectively controlled, so that the aberration of the optical imaging system meets the design requirements, and the edge thicknesses of the fourth lens and the fifth lens are controlled, enabling the fourth lens and the fifth lens to exhibit good performance in terms of structural and assembly stability.

[0060] In an exemplary embodiment, the effective focal length f2 of the second lens, the inner diameter d1m of the image side of the first spacer element, and the inner diameter d2s of the object side of the second spacer element may satisfy: 20 < (f2 / d1m)×(f2 / d2s) ≤ 50. By controlling the mutual relationship among the effective focal length of the second lens, the inner diameter of the image side of the first spacer element, and the inner diameter of the object side of the second spacer element, the central axis distance between the second lens and the front lenses (such as the first lens and the third lens) can be reduced, the consistency of the central optical axes of each lens can be ensured, the deviation of the optical axis during the assembly process can be reduced, and the imaging quality of the optical imaging system can be improved.

[0061] In an exemplary embodiment, the effective focal length f2 of the second lens, the refractive index N2 of the second lens, and the interval EP12 between the first spacer element and the second spacer element along the optical axis may satisfy: 10 < |f2 / N2| / EP12 ≤ 21. By restricting the effective focal length and refractive index of the second lens within a certain range while constraining the interval between the first spacer element and the second spacer element along the optical axis, it is beneficial to the adjustment of the lens structure and reduces the processing difficulty of the lens while ensuring that the light transmission amount of the optical imaging system meets the requirements.

[0062] In an exemplary embodiment, the total effective focal length f of the optical imaging system, the outer diameter D0s of the object-side end face of the lens barrel, and the inner diameter d1s of the object side of the first spacer element may satisfy: 0.5 < f / (D0s - d1s) ≤ 1.5. By controlling the mutual relationship among the total effective focal length of the optical imaging system, the outer diameter of the object-side end face of the lens barrel, and the inner diameter of the object side of the first spacer element, the molding and assembly appearance of each lens can be ensured, enabling the optical imaging system to meet the performance requirements within a certain total effective focal length and ensuring the stability of the five-piece lens group within the lens barrel.

[0063] In an exemplary embodiment, the outer diameter D0s of the object-side end face of the lens barrel, the inner diameter d0s of the object-side end face of the lens barrel, the interval EP01 between the object-side end face of the lens barrel and the first spacer element along the optical axis, and half of the maximum field angle Semi-FOV of the optical imaging system may satisfy: 2.5 < (D0s - d0s) / (EP01 × tan(Semi-FOV)) < 6.0. By controlling the relationship between the outer and inner diameters of the object-side end face of the lens barrel, the interval between the object-side end face of the lens barrel and the first spacer element along the optical axis, and half of the maximum field angle of the optical imaging system, the size of the optical imaging system can be effectively reduced, the optical performance of the optical imaging system can be ensured, and it is easier for accessory processing and injection molding, as well as stable assembly.

[0064] In an exemplary embodiment, the outer diameter D0m of the image-side end face of the lens barrel, the inner diameter d1s of the object-side face of the first spacer element, the length L of the lens barrel in the direction of the optical axis, and the interval EP01 between the object-side end face of the lens barrel and the first spacer element along the optical axis may satisfy: 1.5 < (D0m - d1s) / (L - EP01) < 2.5. By controlling the relationship between the outer diameter of the image-side end face of the lens barrel, the inner diameter of the object-side face of the first spacer element, the length of the lens barrel in the direction of the optical axis, and the interval between the object-side end face of the lens barrel and the first spacer element along the optical axis, while ensuring that the incident light flux of the optical imaging system meets the requirements and providing sufficient adjustable space for the optical imaging system, the interval between the object-side end face of the lens barrel and the first spacer element along the optical axis can be restricted, ensuring the molding and assembly stability of the first lens during the assembly process.

[0065] In an exemplary embodiment, the effective focal length f5 of the fifth lens, the inner diameter d4s of the object-side face of the fourth spacer element, and the inner diameter d5s of the object-side face of the fifth spacer element may satisfy: -2.0 < f5 / (d5s - d4s) ≤ -1.0. While restricting the effective focal length of the fifth lens within a certain range, the inner diameters of the object-side faces of the rear spacer elements (such as the fourth spacer element and the fifth spacer element) are restricted, enabling the optical performance of the optical imaging system to meet the requirements, ensuring the light flux, improving the imaging quality of light, and avoiding ghost images and stray light formed by the reflection of excess light between the lenses.

[0066] In an exemplary embodiment, the optical imaging system may further satisfy: 5.0 < dis / ((Ni - 1)×CTi) < 55.0, where i = 1, 3, 4 or 5. When i = 1, Ni represents the refractive index of the first lens, CTi represents the central thickness of the first lens on the optical axis, and dis represents the inner diameter of the object side surface of the first spacer element; when i = 3, Ni represents the refractive index of the third lens, CTi represents the central thickness of the third lens on the optical axis, and dis represents the inner diameter of the object side surface of the third spacer element; when i = 4, Ni represents the refractive index of the fourth lens, CTi represents the central thickness of the fourth lens on the optical axis, and dis represents the inner diameter of the object side surface of the fourth spacer element; when i = 5, Ni represents the refractive index of the fifth lens, CTi represents the central thickness of the fifth lens on the optical axis, and dis represents the inner diameter of the object side surface of the fifth spacer element. The refractive indices of the first lens, the third lens to the fifth lens are all less than 1.6. By controlling the mutual relationship between the refractive index, the central thickness of the lenses with refractive indices less than 1.6 and the inner diameter of the object side surface of the spacer element at the position of the lens, it is possible to ensure that the light passing amount of the optical imaging system meets the optical requirements, and ensure the structural adjustability of these lenses to match optical imaging systems of different sizes. It is also possible to control the turning angle of the edge field surface and reduce the sensitivity of the optical imaging system. By using the above spacer element, it is possible to block the excess light in the imaging light rays while avoiding the generation of stray light ghosts.

[0067] In an exemplary embodiment, the optical imaging system further includes an aperture stop, and the aperture stop is disposed between the object side and the first lens.

[0068] The optical imaging system according to the above embodiment of the present application may employ five lenses and multiple spacer elements. By reasonably allocating the parameters of each lens and each spacer element, it is possible to reduce the sensitivity of the optical imaging system, improve the stray light phenomenon of the optical imaging system, and enhance the assembly stability, assembly yield and imaging quality of the optical imaging system.

[0069] In an embodiment of the present application, at least one of the lens surfaces of each of the first lens to the fifth lens is an aspherical lens surface. The characteristics of an aspherical lens are that the curvature changes continuously from the center of the lens to the periphery of the lens. Different from a spherical lens with a constant curvature from the center of the lens to the periphery of the lens, an aspherical lens has better curvature radius characteristics and has the advantages of improving distortion aberration and improving astigmatism aberration. After using an aspherical lens, it is possible to eliminate the aberration that appears during imaging as much as possible, and thus improve the imaging quality. Optionally, both the object side surface and the image side surface of each of the first lens to the fifth lens are aspherical lens surfaces.

[0070] However, those skilled in the art will appreciate that, without departing from the technical solution claimed in the present application, the number of lenses and spacer elements of the optical imaging system may be changed to obtain the various results and advantages described in this specification.

[0071] Specific embodiments of the optical imaging system applicable to the above-mentioned embodiments will be further described below with reference to the accompanying drawings.

[0072] First embodiment

[0073] The following reference Figures 2 to 6D An optical imaging system according to a first embodiment of the present application is described. Figure 2 A schematic structural diagram of a five-lens lens assembly of an optical imaging system according to a first embodiment of the present application is shown; Figures 3 to 5 Overall schematic diagrams of an optical imaging system 110 according to Example 1, an optical imaging system 120 according to Example 2, and an optical imaging system 130 according to Example 3 are respectively shown according to the first embodiment of the present application.

[0074] like Figures 2 to 5 As shown, optical imaging systems 110, 120, and 130 each include a lens barrel P0 and a five-lens lens group and a spacer element group disposed within the lens barrel P0. The five-lens lens group includes, from the object side to the image side, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, and a fifth lens E5. An aperture stop STO can be positioned between the object side and the first lens E1 as needed. The spacer element group includes a first spacer element P1, a second spacer element P2, a third spacer element P3, a fourth spacer element P4, and a fifth spacer element P5. The spacers prevent excess light from entering the next lens during the imaging process, ensuring better support between the lenses and the lens barrel P0 and enhancing the structural stability of the optical imaging system.

[0075] The first lens E1 has positive refractive power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens E2 has negative refractive power, with its object-side surface S3 being convex and its image-side surface S4 being concave. The third lens E3 has positive refractive power, with its object-side surface S5 being concave and its image-side surface S6 being convex. The fourth lens E4 has positive refractive power, with its object-side surface S7 being convex and its image-side surface S8 being convex. The fifth lens E5 has negative refractive power, with its object-side surface S9 being convex and its image-side surface S10 being concave. The filter E6 has an object-side surface S11 and an image-side surface S12. Light from an object sequentially passes through each of the surfaces S1 to S12 and is ultimately imaged on the imaging surface S13.

[0076] Table 1 shows basic parameters of the optical imaging system of the first embodiment, wherein the units of curvature radius, thickness / distance and focal length are all millimeters (mm).

[0077]

[0078]

[0079] Table 1

[0080] In this embodiment, the total effective focal length f of the optical imaging system is 3.13 mm, and the maximum field of view FOV of the optical imaging system is 88.6°.

[0081] In the first embodiment, the object side surface and the image side surface of any one of the first lens E1 to the fifth lens E5 are both aspherical surfaces, and the surface shape x of each aspherical lens can be defined by, but not limited to, the following aspherical surface formula:

[0082]

[0083] Wherein, x is the distance vector height from the vertex of the aspheric surface when the aspheric surface is at a height of h along the optical axis; c is the paraxial curvature of the aspheric surface, c = 1 / R (i.e., the paraxial curvature c is the reciprocal of the curvature radius R in Table 1 above); k is the conic coefficient; Ai is the correction coefficient of the i-th order of the aspheric surface. Table 2 shows the high-order coefficients A4, A6, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, A22, A23, A24, A25, A26, A27, A28, A29, A30, A31, A32, A33, A34, A35, A36, A37, A38, A39 10 、A 12 、A 14 、A 16 、A 18 and A 20 .

[0084]

[0085] Table 2

[0086] The optical imaging systems 110, 120, and 130 in Examples 1, 2, and 3 of the first embodiment differ in the structural dimensions of the lens barrels and spacer elements included therein. Table 3 lists some parameters of the lens barrels and spacer elements of the optical imaging systems 110, 120, and 130 of the first embodiment, such as d1s, d1m, d2s, D2m, D3s, d4s, d5s, d0s, D0s, D0m, EP01, EP12, CP3, EP34, CP4, EP45, L, and d3s. Some of the parameters listed in Table 3 are based on Figure 1 The measurement is performed using the marking method shown, where the unit of the parameter is millimeter.

[0087] Example / Parameters d1s d1m d2s D2m D3s d4s d5s d0s D0s 1-1 1.533 1.5962 1.6819 4.7742 5.4801 4.3143 5.487 2.0622 5.3178 1-2 1.5462 1.5850 1.6789 2.5774 5.4919 3.7649 5.487 2.0622 4.8517 1-3 1.5462 1.5850 1.6789 2.5774 6.2372 3.753 5.9383 2.0622 4.3404 Example / Parameters D0m EP01 EP12 CP3 EP34 CP4 EP45 L d3s 1-1 7.0413 0.6088 0.3701 0.0220 0.4928 0.388 0.5185 3.5979 2.3306 1-2 7.0413 0.5735 0.4037 0.0224 0.5634 0.2359 0.5508 3.5979 2.4438 1-3 8.0786 0.6033 0.3742 0.1209 0.518 0.0445 0.5865 3.5979 2.4438

[0088] Table 3

[0089] Figure 6AThe axial chromatic aberration curve of the optical imaging system of the first embodiment is shown, which indicates the deviation of the focal point of light of different wavelengths after passing through the optical imaging system. Figure 6B The astigmatism curve of the optical imaging system of the first embodiment is shown, which represents the meridional image curvature and sagittal image curvature corresponding to different image heights. Figure 6C The distortion curve of the optical imaging system of the first embodiment is shown, which represents the distortion magnitude values ​​corresponding to different image heights. Figure 6D The chromatic aberration curve of the optical imaging system of the first embodiment is shown, which represents the deviation of different image heights on the imaging surface after the light passes through the system. 6A to 6D It can be seen that the optical imaging system of the first embodiment can achieve good imaging quality.

[0090] Second embodiment

[0091] The following reference Figures 7 to 11D An optical imaging system according to a second embodiment of the present application is described. Figure 7 A schematic structural diagram of a five-lens lens assembly of an optical imaging system according to a second embodiment of the present application is shown; Figure 8 、 Figure 9 、 Figure 10 Overall schematic diagrams of an optical imaging system 210 according to Example 1, an optical imaging system 220 according to Example 2, and an optical imaging system 230 according to Example 3 are respectively shown according to the second embodiment of the present application.

[0092] like Figures 7 to 10 As shown, optical imaging systems 210, 220, and 230 each include a lens barrel P0 and a five-lens lens assembly and a spacer assembly disposed within the lens barrel P0. The five-lens lens assembly comprises, from the object side to the image side, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, and a fifth lens E5. An aperture stop STO can be positioned between the object side and the first lens E1 as needed. The spacer assembly comprises a first spacer P1, a second spacer P2, a third spacer P3, a fourth spacer P4, and a fifth spacer P5. The spacers prevent excess light from entering the next lens during the imaging process, ensuring better support between the lenses and the lens barrel P0 and enhancing the structural stability of the optical imaging system.

[0093] The first lens E1 has positive refractive power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens E2 has negative refractive power, with its object-side surface S3 being concave and its image-side surface S4 being concave. The third lens E3 has positive refractive power, with its object-side surface S5 being convex and its image-side surface S6 being convex. The fourth lens E4 has positive refractive power, with its object-side surface S7 being convex and its image-side surface S8 being convex. The fifth lens E5 has negative refractive power, with its object-side surface S9 being concave and its image-side surface S10 being concave. The filter E6 has an object-side surface S11 and an image-side surface S12. Light from an object sequentially passes through each of the surfaces S1 to S12 and is ultimately imaged on the imaging surface S13.

[0094] Table 4 shows a basic parameter table of the optical imaging system of the second embodiment, wherein the units of the curvature radius, thickness / distance and focal length are all millimeters (mm).

[0095]

[0096] Table 4

[0097] In this embodiment, the total effective focal length f of the optical imaging system is 3.16 mm, and the maximum field of view FOV of the optical imaging system is 86.0°.

[0098] In the second embodiment, the object side surface and the image side surface of any one of the first lens E1 to the fifth lens E5 are aspherical surfaces. Table 5 shows the high-order coefficients A4, A6, A8, A9, A10, A20, A30, A40, A60, A70, A80, A90, A10 ... 10 、A 12 、A 14 、A 16 、A 18 and A 20 .

[0099]

[0100]

[0101] Table 5

[0102] The optical imaging systems 210, 220, and 230 in Examples 1, 2, and 3 of the second embodiment differ in the structural dimensions of the lens barrels and spacer elements included therein. Table 6 lists some parameters of the lens barrels and spacer elements of the optical imaging systems 210, 220, and 230 of the second embodiment, such as d1s, d1m, d2s, D2m, D3s, d4s, d5s, d0s, D0s, D0m, EP01, EP12, CP3, EP34, CP4, EP45, L, and d3s. Some of the parameters listed in Table 6 are based on Figure 1The measurement is performed using the marking method shown, where the unit of the parameter is millimeter.

[0103] Example / Parameters d1s d1m d2s D2m D3s d4s d5s d0s D0s 2-1 1.6326 1.8142 1.7638 4.9446 5.5954 3.6062 5.5894 2.0598 4.2264 2-2 1.6146 1.6814 1.7509 2.5406 5.0810 3.6310 5.7691 2.3447 4.8692 2-3 1.6146 1.6814 1.7949 4.6784 5.4948 3.6102 5.6753 2.3447 4.2220 Example / Parameters D0m EP01 EP12 CP3 EP34 CP4 EP45 L d3s 2-1 8.0611 0.5701 0.4063 0.0220 0.5341 0.0220 0.6677 3.8034 2.5381 2-2 7.8578 0.7005 0.3962 0.3168 0.3706 0.0220 0.6707 3.9644 2.4332 2-3 7.1168 0.7005 0.4277 0.0601 0.4528 0.0311 0.5622 3.9581 2.6409

[0104] Table 6

[0105] Figure 11A An axial chromatic aberration curve of the optical imaging system of the second embodiment is shown, which indicates the deviation of the focal point of light of different wavelengths after passing through the optical imaging system. Figure 11B The astigmatism curve of the optical imaging system of the second embodiment is shown, which represents the meridional image curvature and sagittal image curvature corresponding to different image heights. Figure 11C The distortion curve of the optical imaging system of the second embodiment is shown, which represents the distortion magnitude values ​​corresponding to different image heights. Figure 11D The chromatic aberration curve of the optical imaging system of the second embodiment is shown, which represents the deviation of different image heights on the imaging surface after the light passes through the system. 11A to 11D It can be seen that the optical imaging system of the second embodiment can achieve good imaging quality.

[0106] Third embodiment

[0107] The following reference Figures 12 to 16D An optical imaging system according to a third embodiment of the present application is described. Figure 12 A schematic structural diagram of a five-lens lens assembly of an optical imaging system according to a third embodiment of the present application is shown; Figure 13 、 Figure 14 、 Figure 15 Overall schematic diagrams of an optical imaging system 310 according to Example 1, an optical imaging system 320 according to Example 2, and an optical imaging system 330 according to Example 3 are respectively shown according to the third embodiment of the present application.

[0108] like Figures 12 to 15 As shown, optical imaging systems 310, 320, and 330 each include a lens barrel P0 and a five-lens lens assembly and a spacer assembly positioned within the lens barrel P0. The five-lens lens assembly, from the object side to the image side, includes: a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, and a fifth lens E5. A stop STO can be positioned between the object side and the first lens E1 as needed. The spacer assembly includes: a first spacer P1, a second spacer P2, a third spacer P3, a fourth spacer P4, and a fifth spacer P5. The spacers prevent excess light from entering the next lens during the imaging process, ensuring better support between the lenses and the lens barrel P0 and enhancing the structural stability of the optical imaging system.

[0109] The first lens E1 has positive refractive power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens E2 has negative refractive power, with its object-side surface S3 being concave and its image-side surface S4 being concave. The third lens E3 has positive refractive power, with its object-side surface S5 being convex and its image-side surface S6 being convex. The fourth lens E4 has positive refractive power, with its object-side surface S7 being convex and its image-side surface S8 being convex. The fifth lens E5 has negative refractive power, with its object-side surface S9 being convex and its image-side surface S10 being concave. The filter E6 has an object-side surface S11 and an image-side surface S12. Light from an object sequentially passes through each of the surfaces S1 to S12 and is ultimately imaged on the imaging surface S13.

[0110] Table 7 shows a basic parameter table of the optical imaging system of the third embodiment, wherein the units of the curvature radius, thickness / distance and focal length are all millimeters (mm).

[0111]

[0112] Table 7

[0113] In this embodiment, the total effective focal length f of the optical imaging system is 3.11 mm, and the maximum field of view FOV of the optical imaging system is 86.1°.

[0114] In the third embodiment, the object side surface and the image side surface of any one of the first lens E1 to the fifth lens E5 are aspherical surfaces. Table 8 shows the high-order coefficients A4, A6, A8, A9, A10, A20, A30, A40, A60, A70, A80, A90, A10 ... 10 、A 12 、A 14 、A 16 、A 18 and A 20 .

[0115]

[0116]

[0117] Table 8

[0118] The optical imaging systems 310, 320, and 330 in Examples 1, 2, and 3 of the third embodiment differ in the structural dimensions of the lens barrels and spacer elements included therein. Table 9 lists some parameters of the lens barrels and spacer elements of the optical imaging systems 310, 320, and 330 of the third embodiment, such as d1s, d1m, d2s, D2m, D3s, d4s, d5s, d0s, D0s, D0m, EP01, EP12, CP3, EP34, CP4, EP45, L, and d3s. Some of the parameters listed in Table 9 are based on Figure 1The measurement is performed using the marking method shown, where the unit of the parameter is millimeter.

[0119] Example / Parameters d1s d1m d2s D2m D3s d4s d5s d0s D0s 3-1 1.5368 1.6505 1.7689 4.9881 5.5347 3.5722 5.8992 2.3697 5.0559 3-2 1.5258 1.5926 1.6762 2.4552 3.9525 3.6963 5.9137 1.9221 4.504 3-3 1.5258 1.5926 1.6762 2.4552 5.8720 3.6963 5.9137 1.9221 4.504 Example / Parameters D0m EP01 EP12 CP3 EP34 CP4 EP45 L d3s 3-1 7.1522 0.6735 0.3829 0.0207 0.6312 0.0207 0.7463 3.9904 2.4929 3-2 7.7881 0.5421 0.4009 0.3191 0.4012 0.025 0.8082 3.8276 3.097 3-3 7.7881 0.5421 0.4009 0.0220 0.5384 0.025 0.8082 3.8276 2.5698

[0120] Table 9

[0121] Figure 16A An axial chromatic aberration curve of the optical imaging system of the third embodiment is shown, which indicates the deviation of the focal point of light of different wavelengths after passing through the optical imaging system. Figure 16B The astigmatism curve of the optical imaging system of the third embodiment is shown, which represents the meridional image curvature and sagittal image curvature corresponding to different image heights. Figure 16C The distortion curve of the optical imaging system of the third embodiment is shown, which represents the distortion magnitude values ​​corresponding to different image heights. Figure 16D The chromatic aberration curve of the optical imaging system of the third embodiment is shown, which represents the deviation of different image heights on the imaging surface after the light passes through the system. 16A to 16D It can be seen that the optical imaging system of the third embodiment can achieve good imaging quality.

[0122] Fourth embodiment

[0123] The following reference Figures 17 to 21D An optical imaging system according to a fourth embodiment of the present application is described. Figure 17 A schematic structural diagram of a five-lens lens assembly of an optical imaging system according to a fourth embodiment of the present application is shown; Figure 18 、 Figure 19 、 Figure 20 Overall schematic diagrams of an optical imaging system 410 according to Example 1, an optical imaging system 420 according to Example 2, and an optical imaging system 430 according to Example 3 are respectively shown according to the fourth embodiment of the present application.

[0124] like Figures 17 to 20 As shown, optical imaging systems 410, 420, and 430 each include a lens barrel P0 and a five-element lens group and a spacer group positioned within the lens barrel P0. The five-element lens group includes, from the object side to the image side, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, and a fifth lens E5. A stop STO can be positioned between the object side and the first lens E1 as needed. The spacer group includes a first spacer P1, a second spacer P2, a third spacer P3, a fourth spacer P4, and a fifth spacer P5. The spacers prevent excess light from entering the next lens during the imaging process, ensuring better support between the lenses and the lens barrel P0 and enhancing the structural stability of the optical imaging system.

[0125] The first lens E1 has positive refractive power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens E2 has negative refractive power, with its object-side surface S3 being concave and its image-side surface S4 being concave. The third lens E3 has negative refractive power, with its object-side surface S5 being convex and its image-side surface S6 being concave. The fourth lens E4 has positive refractive power, with its object-side surface S7 being concave and its image-side surface S8 being convex. The fifth lens E5 has negative refractive power, with its object-side surface S9 being concave and its image-side surface S10 being concave. The filter E6 has an object-side surface S11 and an image-side surface S12. Light from an object sequentially passes through each of the surfaces S1 to S12 and is ultimately imaged on the imaging surface S13.

[0126] Table 10 shows a basic parameter table of the optical imaging system of the fourth embodiment, wherein the units of the curvature radius, thickness / distance and focal length are all millimeters (mm).

[0127]

[0128] Table 10

[0129] In this embodiment, the total effective focal length f of the optical imaging system is 3.81 mm, and the maximum field of view FOV of the optical imaging system is 81.5°.

[0130] In the fourth embodiment, the object side surface and the image side surface of any one of the first lens E1 to the fifth lens E5 are both aspherical surfaces. Table 11 shows the high-order coefficients A4, A6, A8, A9, A10 of each aspherical mirror surface S1-S10 that can be used in the fourth embodiment. 10 、A 12 、A 14 、A 16 、A 18 and A 20 .

[0131]

[0132]

[0133] Table 11

[0134] The optical imaging systems 410, 420, and 430 in Examples 1, 2, and 3 of the fourth embodiment differ in the structural dimensions of the lens barrels and spacer elements included therein. Table 12 lists some parameters of the lens barrels and spacer elements of the optical imaging systems 410, 420, and 430 of the fourth embodiment, such as d1s, d1m, d2s, D2m, D3s, d4s, d5s, d0s, D0s, D0m, EP01, EP12, CP3, EP34, CP4, EP45, L, and d3s. Some of the parameters listed in Table 12 are based on Figure 1The measurement is performed using the marking method shown, where the unit of the parameter is millimeter.

[0135] Example / Parameters d1s d1m d2s D2m D3s d4s d5s d0s D0s 4-1 1.6708 1.7635 1.4612 4.8846 5.8341 4.0372 5.2461 2.0084 4.3335 4-2 1.7043 1.7828 1.4612 4.0866 5.1911 4.0372 5.2461 2.1545 5.1713 4-3 1.6633 1.7559 1.4649 4.9900 4.7724 3.896 5.0812 2.3606 5.6317 Example / Parameters D0m EP01 EP12 CP3 EP34 CP4 EP45 L d3s 4-1 7.1007 0.6491 0.3469 0.0220 0.7159 0.022 0.4551 3.4057 2.5906 4-2 6.9208 0.6981 0.3803 0.0220 0.7466 0.022 0.4551 3.5630 2.3204 4-3 6.7185 0.6767 0.3278 0.2748 0.4846 0.0476 0.3622 3.4188 2.9039

[0136] Table 12

[0137] Figure 21A An on-axis chromatic aberration curve of the optical imaging system of the fourth embodiment is shown, which indicates the deviation of the focal point of light of different wavelengths after passing through the optical imaging system. Figure 21B The astigmatism curve of the optical imaging system of the fourth embodiment is shown, which represents the meridional image curvature and sagittal image curvature corresponding to different image heights. Figure 21C The distortion curve of the optical imaging system of the fourth embodiment is shown, which represents the distortion magnitude values ​​corresponding to different image heights. Figure 21D The chromatic aberration curve of the optical imaging system of the fourth embodiment is shown, which represents the deviation of different image heights on the imaging surface after the light passes through the system. 21A to 21D It can be seen that the optical imaging system of the fourth embodiment can achieve good imaging quality.

[0138] In summary, the conditional expressions of the examples in the first to fourth embodiments satisfy the relationship shown in Table 13.

[0139]

[0140] Table 13

[0141] The above description is merely a preferred embodiment of the present application and an illustration of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to the technical solutions formed by the specific combination of the above-mentioned technical features, but also encompasses other technical solutions formed by any combination of the above-mentioned technical features or their equivalents without departing from the inventive concept. For example, a technical solution formed by replacing the above-mentioned features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. An optical imaging system, characterized in that include: A five-lens lens assembly comprising a first lens having positive refractive power, a second lens having negative refractive power, a third lens, a fourth lens having positive refractive power, and a fifth lens having negative refractive power, arranged in order from the object side to the image side along the optical axis, wherein the object side surface of the first lens is convex and the image side surface is concave; the image side surface of the second lens is concave; the image side surface of the fourth lens is convex; and the image side surface of the fifth lens is concave; a spacer element group, comprising a fourth spacer element and a fifth spacer element, wherein the fourth spacer element is disposed on and in contact with the image side surface of the fourth lens, and the fifth spacer element is disposed on and in contact with the image side surface of the fifth lens; and a lens barrel, wherein the five-piece lens group and the spacer element group are placed in the lens barrel, Wherein, the number of lenses having refractive power in the optical imaging system is five; The effective focal length f5 of the fifth lens, the center thickness CT5 of the fifth lens on the optical axis, the air gap T45 between the fourth lens and the fifth lens on the optical axis, and the gap EP45 between the fourth spacer element and the fifth spacer element along the optical axis satisfy the following conditions: -22.99≤(EP45 / CT5)×(f5 / T45)≤-5.83; The effective focal length f5 of the fifth lens, the inner diameter d4s of the object-side surface of the fourth spacing element, and the inner diameter d5s of the object-side surface of the fifth spacing element satisfy: -1.88≤f5 / (d5s-d4s)<-1.

0.

2. The optical imaging system according to claim 1, wherein: The spacer element group further includes a third spacer element disposed on the image side of the third lens and in contact with the image side of the third lens. The effective focal length f4 of the fourth lens, the air gap T34 between the third lens and the fourth lens on the optical axis, and the maximum thickness CP3 of the third spacing element satisfy: 7.69≤f4 / (T34-CP3)≤22.

59.

3. The optical imaging system according to claim 1, wherein: The spacer element group further includes a second spacer element and a third spacer element, wherein the second spacer element is disposed on the image side of the second lens and contacts the image side of the second lens, and the third spacer element is disposed on the image side of the third lens and contacts the image side of the third lens. The curvature radius R5 of the object side surface of the third lens, the curvature radius R6 of the image side surface of the third lens, the outer diameter D2m of the image side surface of the second spacer element, and the outer diameter D3s of the object side surface of the third spacer element satisfy: |D2m / R5+D3s / R6|≤1.

06.

4. The optical imaging system according to claim 1, wherein: The spacer element group further includes a third spacer element disposed on the image side of the third lens and in contact with the image side of the third lens. The curvature radius R8 of the image side surface of the fourth lens, the maximum thickness CP3 of the third spacer element, and the interval EP34 between the third spacer element and the fourth spacer element along the optical axis satisfy: -10.92≤R8 / (EP34+CP3)≤-2.

32.

5. The optical imaging system according to claim 1, wherein: The effective focal length f4 of the fourth lens, the center thickness CT4 of the fourth lens on the optical axis, the air gap T45 between the fourth lens and the fifth lens on the optical axis, and the maximum thickness CP4 of the fourth spacer element satisfy: 3.43≤f4 / (CT4+T45-CP4)≤7.

05.

6. The optical imaging system according to claim 1, wherein: The spacer element group further includes a first spacer element and a second spacer element, wherein the first spacer element is disposed on the image side of the first lens and in contact with the image side of the first lens, and the second spacer element is disposed on the image side of the second lens and in contact with the image side of the second lens. The effective focal length f2 of the second lens, the inner diameter d1m of the image side surface of the first spacing element, and the inner diameter d2s of the object side surface of the second spacing element satisfy: 22.12≤(f2 / d1m)×(f2 / d2s)≤49.

91.

7. The optical imaging system according to claim 6, wherein: The effective focal length f2 of the second lens, the refractive index N2 of the second lens, and the interval EP12 between the first spacer element and the second spacer element along the optical axis satisfy the following: 11.55≤|f2 / N2| / EP12≤20.

67.

8. The optical imaging system according to claim 1, wherein: The spacer element group further includes a first spacer element disposed on the image side of the first lens and in contact with the image side of the first lens. The total effective focal length f of the optical imaging system, the outer 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 the following relationship: 0.83≤f / (D0s-d1s)≤1.

43.

9. The optical imaging system according to claim 8, wherein: The outer diameter D0s of the object side end surface of the lens barrel, the inner diameter d0s of the object side end surface of the lens barrel, the interval EP01 between the object side end surface of the lens barrel and the first spacing element along the optical axis, and half of the maximum field of view Semi-FOV of the optical imaging system satisfy: 2.87≤(D0s-d0s) / (EP01×tan(Semi-FOV))≤5.

61.

10. The optical imaging system according to claim 8, wherein: The outer diameter D0m of the image-side end surface of the lens barrel, the inner diameter d1s of the object-side surface of the first spacer element, the length L of the lens barrel in the direction of the optical axis, and the interval EP01 between the object-side end surface of the lens barrel and the first spacer element along the optical axis satisfy the following conditions: 1.69≤(D0m-d1s) / (L-EP01)≤2.

18.

11. The optical imaging system according to claim 1, wherein: The spacer element group further includes a first spacer element and a third spacer element, wherein the first spacer element is disposed on the image side of the first lens and contacts the image side of the first lens, and the third spacer element is disposed on the image side of the third lens and contacts the image side of the third lens. Wherein, the optical imaging system further satisfies: 6.12≤dis / ((Ni-1)×CTi)≤54.45, i=1, 3, 4 or 5, Wherein, when i is 1, Ni represents the refractive index of the first lens, CTi represents the center thickness of the first lens on the optical axis, and dis represents the inner diameter of the object side of the first spacer element; when i is 3, Ni represents the refractive index of the third lens, CTi represents the center thickness of the third lens on the optical axis, and dis represents the inner diameter of the object side of the third spacer element; when i is 4, Ni represents the refractive index of the fourth lens, CTi represents the center thickness of the fourth lens on the optical axis, and dis represents the inner diameter of the object side of the fourth spacer element; when i is 5, Ni represents the refractive index of the fifth lens, CTi represents the center thickness of the fifth lens on the optical axis, and dis represents the inner diameter of the object side of the fifth spacer element.

12. The optical imaging system according to any one of claims 1 to 11, characterized in that: An absolute value of the effective focal length of the second lens is greater than an absolute value of the effective focal length of the fifth lens.

13. The optical imaging system according to any one of claims 1 to 11, characterized in that: The outer diameters of the first lens and the second lens are smaller than the outer diameter of the object-side end surface of the lens barrel.

Images