Optical imaging system

Abstract

The application discloses an optical imaging system, comprising: an imaging lens group, comprising 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 sequence along an optical axis from an object side to an image side; and a plurality of spacer elements, comprising a fourth spacer element located between the fourth lens and the fifth lens and in contact with an image side surface of the fourth lens, a fifth spacer element located between the fifth lens and the sixth lens and in contact with an image side surface of the fifth lens, and a sixth spacer element located between the sixth lens and the seventh lens and in contact with an image side surface of the sixth lens; wherein an effective focal length f5 of the fifth lens, an outer diameter D4m of an image side surface of the fourth spacer element, an outer diameter D5m of an image side surface of the fifth spacer element and an outer diameter D6m of an image side surface of the sixth spacer element satisfy: -6.0 < f5 / (D4m+D5m+D6m) < 20.0.

Description

Technical Field

[0001] This application relates to the field of optical components, and more specifically, to an optical imaging system. Background Technology

[0002] With the continuous advancement of technology, electronic products have flourished. Nowadays, electronic products are increasingly trending towards thinner, lighter, and higher-quality designs. Conventional mobile phone lens designs are no longer sufficient to meet the evolving needs of modern mobile phones. Mobile phone lenses are moving towards multi-element designs while simultaneously maintaining a slim profile. This means that the space occupied by a single lens is shrinking, and the design difficulty is increasing. Overcoming these challenges and designing an optical imaging system that combines miniaturization, stable assembly, and high image quality still presents significant room for exploration.

[0003] In existing technologies, eight-element optical imaging systems have the problem of large space occupancy, while reducing the space occupancy will result in unstable assembly and excessive stray light. Summary of the Invention

[0004] This application provides an optical imaging system comprising: an imaging lens group including 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 sequentially along the optical axis from the object side to the image side; and a plurality of spacer elements, including a fourth spacer element located between the fourth and fifth lenses and in contact with the image side of the fourth lens, a fifth spacer element located between the fifth and sixth lenses and in contact with the image side of the fifth lens, and a sixth spacer element located between the sixth and seventh lenses and in contact with the image side of the sixth lens; wherein the effective focal length f5 of the fifth lens, the outer diameter D4m of the image side of the fourth spacer element, the outer diameter D5m of the image side of the fifth spacer element, and the outer diameter D6m of the image side of the sixth spacer element satisfy: -6.0 < f5 / (D4m+D5m+D6m) < 20.0.

[0005] In one embodiment, the optical imaging system further includes a lens barrel for accommodating an imaging lens group and a plurality of spacer elements, wherein the outer diameter D0m of the image-side end of the lens barrel and the radius of curvature R9 of the object-side surface of the fifth lens satisfy: -3.0 < R9 / D0m < 1.0.

[0006] In one embodiment, the maximum thickness CP4 of the fourth spacer element, the spacing EP45 between the fourth and fifth spacers along the optical axis, the air gap T45 between the fourth and fifth lenses on the optical axis, and the radius of curvature R11 of the object side surface of the sixth lens satisfy: -19.0 < R11 / (CP4+T45+EP45) < -10.0.

[0007] In one embodiment, the plurality of spacers further includes a seventh spacer located between the seventh lens and the eighth lens and in contact with the image side of the seventh lens. The maximum thickness CP5 of the fifth spacer, the maximum thickness CP7 of the seventh spacer, the effective focal length f7 of the seventh lens, and the air gap T56 between the fifth lens and the sixth lens on the optical axis satisfy: -55.0 < f7 / (CP5+T56+CP7) < -10.0.

[0008] In one embodiment, the plurality of spacers further includes a second spacer located between the second lens and the third lens and in contact with the image-side surface of the second lens. The radius of curvature R10 of the image-side surface of the fifth lens, the maximum thickness CP2 of the second spacer, the center thickness CT2 of the second lens on the optical axis, the center thickness CT3 of the third lens on the optical axis, and the air gap T23 between the second lens and the third lens on the optical axis satisfy: 11.0 < R10 / (CT2+CP2+T23+CT3) < 71.0.

[0009] In one embodiment, the plurality of spacers further includes a second spacer located between the second lens and the third lens and in contact with the image side of the second lens. The outer diameter D2s of the object side of the second spacer, the radius of curvature R4 of the image side of the second lens, and the effective focal length f2 of the second lens satisfy: -5.5 < f2 / D2s + D2s / R4 < -2.5.

[0010] In one embodiment, the plurality of spacers further includes a first spacer element located between the first lens and the second lens and in contact with the image side of the first lens. The outer diameter D1s of the object side of the first spacer element, the radius of curvature R1 of the object side of the first lens, the effective focal length f5 of the fifth lens and the effective focal length f7 of the seventh lens satisfy: -7.5 < f5 / f7 + D1s / R1 < 6.0.

[0011] In one embodiment, the plurality of spacers further includes a third spacer located between the third lens and the fourth lens and in contact with the image side of the third lens, wherein the inner diameter D3s of the object side of the third spacer and the radius of curvature R7 of the object side of the fourth lens satisfy: -11.0 < R7 / d3s < -6.0.

[0012] In one embodiment, the plurality of spacers further includes a third spacer located between the third lens and the fourth lens and in contact with the image side of the third lens. The outer diameter D3m of the image side of the third spacer, the outer diameter D5s of the object side of the fifth spacer, the spacing EP34 between the third spacer and the fourth spacer along the optical axis, and the effective focal length f4 of the fourth lens satisfy: -110.0 < (f4 + D5s + D3m) / EP34 < -40.0.

[0013] In one embodiment, the object-side radius of curvature of the second lens is positive, and the image-side radius of curvature is positive.

[0014] In one embodiment, the radius of curvature of the object-side surface of the third lens is positive.

[0015] In one embodiment, the radius of curvature of the image-side surface of the sixth lens is negative.

[0016] In one embodiment, the seventh lens has negative optical power and a positive radius of curvature on its object-side surface.

[0017] In one embodiment, the eighth lens has negative optical power and a negative radius of curvature on its object-side surface.

[0018] The optical imaging system of this application intercepts excess non-imaging light rays by incorporating multiple spacer elements. Simultaneously, it controls the radius of curvature of the effective portion of each lens, effectively reducing the generation of reflected light paths at the lens positions, minimizing stray light and ghosting phenomena, and improving the quality of the optical imaging system. The optical imaging system of this application has at least one beneficial effect, including weak ghosting, high imaging quality, less stray light, and good assembly stability. Attached Figure Description

[0019] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0020] Figure 1A A structural layout diagram and schematic diagram of some parameters of an optical imaging system according to this application are shown;

[0021] Figure 1B It shows Figure 1A A schematic diagram showing the spacer element in the optical imaging system reducing stray light;

[0022] Figure 2A and Figure 2B Schematic diagrams of two optical imaging systems according to Embodiment 1 of this application are shown;

[0023] Figures 3A to 3D The on-axis chromatic aberration curve, astigmatism curve, distortion curve, and magnification chromatic aberration curve of the optical imaging system according to Embodiment 1 of this application are shown respectively.

[0024] Figure 4A and Figure 4B Schematic diagrams of two optical imaging systems according to Embodiment 2 of this application are shown;

[0025] Figures 5A to 5D The on-axis chromatic aberration curve, astigmatism curve, distortion curve, and magnification chromatic aberration curve of the optical imaging system according to Embodiment 2 of this application are shown respectively.

[0026] Figure 6A and Figure 6B Schematic diagrams of two optical imaging systems according to Embodiment 3 of this application are shown; and

[0027] Figures 7A to 7D The on-axis chromatic aberration curve, astigmatism curve, distortion curve, and magnification chromatic aberration curve of the optical imaging system according to Embodiment 3 of this application are shown. Detailed Implementation

[0028] To better understand this application, various aspects of this application will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed descriptions are merely illustrative of exemplary embodiments of this application and are not intended to limit the scope of this application in any way. Throughout the specification, the same reference numerals refer to the same elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0029] It should be noted that in this specification, the terms "first," "second," "third," etc., are used only to distinguish one feature from another and do not imply any limitation on the features. Therefore, without departing from the teachings of this application, the first lens discussed below may also be referred to as the second lens or the third lens.

[0030] In the accompanying drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for ease of illustration. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are illustrated by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustrative purposes only and are not drawn strictly to scale.

[0031] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the location of the convexity is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the location of the concaveness is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the subject is called the object-side surface of the lens, and the surface of each lens closest to the imaging plane is called the image-side surface of the lens.

[0032] It should also be understood that the terms "comprising," "including," "having," "containing," and / or "comprising," when used in this specification, indicate the presence of the stated features, elements, and / or components, but do not exclude the presence or addition of one or more other features, elements, components, and / or combinations thereof. Furthermore, when expressions such as "at least one of..." appear after a list of listed features, they modify the entire list of features, not individual elements in the list. Additionally, when describing embodiments of this application, the word "may" is used to mean "one or more embodiments of this application." And the term "exemplary" is intended to refer to an example or illustration.

[0033] Unless otherwise specified, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It should also be understood that terms (e.g., those defined in common dictionaries) shall be interpreted as having the meaning consistent with their meaning in the context of the relevant art and shall not be interpreted in an idealized or overly formalized sense, unless expressly so specified herein.

[0034] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The following embodiments only illustrate several implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be pointed out that, for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. For example, the imaging lens group, lens barrel, and spacer element in the various embodiments of this application can be arbitrarily combined, and it is not limited to the imaging lens group in one embodiment being combined only with the lens barrel, spacer element, etc. of that embodiment.

[0035] The present application will now be described in detail with reference to the accompanying drawings and embodiments. Figure 1A This diagram illustrates the structural layout of an optical imaging system according to this application, along with schematic diagrams of some parameters. Those skilled in the art will understand that some parameters frequently used in the art, such as the air gap T45 between the fourth and fifth lenses on the optical axis, are not shown. Figure 1A As shown in the figure, Figure 1A The following are only some parameters of the lens barrel and spacer element of an optical imaging system of this application, in order to better understand the present invention.

[0036] An optical imaging system according to an exemplary embodiment of this application may include an imaging lens group and multiple spacer elements. The imaging lens group may include eight lenses with optical power, namely 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 sequentially along the optical axis from the object side to the image side. The multiple spacer elements include: a fourth spacer element located between the fourth and fifth lenses and in contact with the image-side surface of the fourth lens; a fifth spacer element located between the fifth and sixth lenses and in contact with the image-side surface of the fifth lens; and a sixth spacer element located between the sixth and seventh lenses and in contact with the image-side surface of the sixth lens. The optical imaging system of this application, by incorporating multiple spacer elements, intercepts excess non-imaging light rays and controls the radius of curvature of the effective portion of each lens, effectively reducing the generation of reflected light paths at the lens positions, reducing stray light and ghosting phenomena, and improving lens quality.

[0037] In an exemplary implementation, such as Figure 1A As shown, there is at least one spacer element between any two adjacent lenses from the first lens to the eighth lens. That is, the multiple spacer elements include: a first spacer element P1 located between the first lens and the second lens and in contact with the image side of the first lens; a second spacer element P2 located between the second lens and the third lens and in contact with the image side of the second lens; a third spacer element P3 located between the third lens and the fourth lens and in contact with the image side of the third lens; a fourth spacer element P4 located between the fourth lens and the fifth lens and in contact with the image side of the fourth lens; a fifth spacer element P5 located between the fifth lens and the sixth lens and in contact with the image side of the fifth lens; a sixth spacer element P6 located between the sixth lens and the seventh lens and in contact with the image side of the sixth lens; a seventh spacer element P7 located between the seventh lens and the eighth lens and in contact with the image side of the seventh lens; and an eighth spacer element P7b located between the seventh lens and the eighth lens and in contact with the object side of the eighth lens.

[0038] Figure 1B It shows Figure 1A The diagram illustrates how the spacer elements in the optical imaging system reduce stray light. A beam of light is reflected between the first spacer element P1 and the second spacer element P2 and is effectively blocked from entering the rear lens. The dashed line represents the path of this light beam entering the rear lens if it were not blocked. Therefore, the optical imaging system of this application, by incorporating multiple spacer elements, can effectively block non-imaging light paths, reduce stray light, and ensure the imaging effect of the lens.

[0039] In an exemplary embodiment, the first lens of the optical imaging system according to this application may have positive or negative optical power; the second lens may have positive or negative optical power, with a positive radius of curvature on both the object-side and image-side surfaces; the third lens may have positive or negative optical power, with a positive radius of curvature on both the object-side and image-side surfaces; the fourth lens may have positive or negative optical power; the fifth lens may have positive or negative optical power; the sixth lens may have positive or negative optical power, with a negative radius of curvature on both the image-side and image-side surfaces; the seventh lens has negative optical power, with a positive radius of curvature on both the object-side and image-side surfaces; and the eighth lens has negative optical power, with a negative radius of curvature on both the object-side and image-side surfaces. By reasonably controlling the positive and negative distribution of the optical power of each lens in the optical imaging lens group, the low-order aberrations of the optical imaging lens group can be effectively balanced and controlled, and the sensitivity to tolerances can be reduced, maintaining the miniaturization of the system.

[0040] In an exemplary embodiment, the optical imaging system according to this application satisfies: -6.0 < f5 / (D4m+D5m+D6m) < 20.0, where f5 is the effective focal length of the fifth lens, D4m is the outer diameter of the image-side surface of the fourth spacer element, and D5m is the outer diameter of the image-side surface of the fifth spacer element (e.g., f5 is the effective focal length of the fifth lens, D4m is the outer diameter of the image-side surface of the fourth spacer element, and D5m is the outer diameter of the image-side surface of the fifth spacer element). Figure 1A As shown in the diagram, D6m is the outer diameter of the image-side surface of the sixth spacer element. More specifically, f5, D4m, D5m, and D6m can further satisfy: -5.41 < f5 / (D4m+D5m+D6m) < 19.12. Satisfying -6.0 < f5 / (D4m+D5m+D6m) < 20.0 is beneficial for ensuring the relative illumination of the lens, blocking more unnecessary non-imaging light rays, and ensuring lens quality; at the same time, controlling the optical power of the fifth lens is beneficial for controlling the direction of light rays and improving image quality.

[0041] In an exemplary embodiment, the optical imaging system according to this application satisfies: -110.0 < (f4 + D5s + D3m) / EP34 < -40.0, where, as Figure 1A As shown, D3m is the outer diameter of the image-side surface of the third spacer element, D5s is the outer diameter of the object-side surface of the fifth spacer element, EP34 is the spacing between the third and fourth spacer elements along the optical axis, and f4 is the effective focal length of the fourth lens. More specifically, f4, D5s, D3m, and EP34 can further satisfy: -102.99 < (f4 + D5s + D3m) / EP34 < -40.23. Satisfying -110.0 < (f4 + D5s + D3m) / EP34 < -40.0 is beneficial for improving the uniformity of the third spacer element, the fourth lens, the fourth spacer element, the fifth lens, and the internal structure of the fifth spacer element, and for improving assembly stability.

[0042] In an exemplary embodiment, the optical imaging system according to this application satisfies: -3.0 < R9 / D0m < 1.0, wherein the optical imaging system further includes a lens barrel for accommodating an imaging lens group and a plurality of spacer elements, such as Figure 1A As shown, D0m is the outer diameter of the image-side end of the lens barrel, and R9 is the radius of curvature of the object-side surface of the fifth lens. More specifically, R9 and D0m can further satisfy: -2.78 < R9 / D0m < 0.80. By controlling the radius of curvature of the object-side surface of the fifth lens, the projection height of light on the fifth surface can be adjusted, thereby controlling the effective aperture of the next surface. Reasonably setting the outer diameter of the image-side end of the optical imaging system can effectively control the matching between the optical imaging system and the downstream photosensitive element, which is beneficial to the assembly consistency of the optical imaging system.

[0043] In an exemplary embodiment, the optical imaging system according to this application satisfies: -19.0 < R11 / (CP4+T45+EP45) < -10.0, where, as Figure 1A As shown, CP4 is the maximum thickness of the fourth spacer element, EP45 is the spacing between the fourth and fifth spacers along the optical axis, T45 is the air gap between the fourth and fifth lenses along the optical axis, and R11 is the radius of curvature of the object-side surface of the sixth lens. More specifically, R11, CP4, T45, and EP45 can further satisfy: -18.86 < R11 / (CP4+T45+EP45) < -13.08. Satisfying -19.0 < R11 / (CP4+T45+EP45) < -10.0, the outer diameter difference between the fifth and sixth lenses is rationally designed, ensuring that both lenses have an excellent outer diameter difference within the ratio range, further guaranteeing the uniformity of the radial and axial dimensions of the fifth and sixth lenses. This design is beneficial to the stability of the sixth lens assembly process and improves product yield.

[0044] In an exemplary embodiment, the optical imaging system according to this application satisfies: -55.0 < f7 / (CP5+T56+CP7) < -10.0, where CP5 is the maximum thickness of the fifth spacer element, CP7 is the maximum thickness of the seventh spacer element, f7 is the effective focal length of the seventh lens, and T56 is the air gap between the fifth and sixth lenses on the optical axis. More specifically, f7, CP5, T56, and CP7 can further satisfy: -50.57 < f7 / (CP5+T56+CP7) < -12.03. Satisfying -55.0 < f7 / (CP5+T56+CP7) < -10.0 is beneficial for controlling the radial difference in the dimensions of the bearing position between the sixth and seventh lenses, ensuring the stability of the lens structure between the sixth and seventh lenses; at the same time, controlling the inner diameter of the fifth spacer element ensures a high relative illumination of the optical imaging system and reduces the area after the fifth spacer element from stray light.

[0045] In an exemplary embodiment, the optical imaging system according to this application satisfies: 11.0 < R10 / (CT2+CP2+T23+CT3) < 71.0, where R10 is the radius of curvature of the image-side surface of the fifth lens, CP2 is the maximum thickness of the second spacer element, CT2 is the center thickness of the second lens on the optical axis, CT3 is the center thickness of the third lens on the optical axis, and T23 is the air gap between the second and third lenses on the optical axis. More specifically, R10, CT2, CP2, T23, and CT3 further satisfy: 11.85 < R10 / (CT2+CP2+T23+CT3) < 70.81. Satisfying 11.0 < R10 / (CT2+CP2+T23+CT3) < 71.0 helps ensure the uniformity of the overall structure of the second and third lenses, effectively improves the forming stability of the lenses, increases the resistance of the lenses to changes under environmental testing conditions, and further enhances the quality of the optical imaging system.

[0046] In an exemplary embodiment, the optical imaging system according to this application satisfies: -5.5 < f2 / D2s + D2s / R4 < -2.5, where D2s is the outer diameter of the object-side surface of the second spacer element, R4 is the radius of curvature of the image-side surface of the second lens, and f2 is the effective focal length of the second lens. More specifically, f2, D2s, D2s, and R4 further satisfy: -5.22 < f2 / D2s + D2s / R4 < -2.81. Satisfying -5.5 < f2 / D2s + D2s / R4 < -2.5, and by reasonably setting the radius of curvature of the second lens and the size of the adjacent second spacer elements, the reflected light path through the image-side surface of the second lens and the light penetrating to the next lens through this position can be minimized, reducing stray light and ghosting.

[0047] In an exemplary embodiment, the optical imaging system according to this application satisfies: -7.5 < f5 / f7 + D1s / R1 < 6.0, where D1s is the outer diameter of the object-side surface of the first spacer element, R1 is the radius of curvature of the object-side surface of the first lens, f5 is the effective focal length of the fifth lens, and f7 is the effective focal length of the seventh lens. More specifically, f5, f7, D1s, and R1 further satisfy: -7.29 < f5 / f7 + D1s / R1 < 5.72. Satisfying -7.5 < f5 / f7 + D1s / R1 < 6.0, and reasonably setting the radius of curvature of the first lens and the size of the adjacent first spacer element, can minimize the reflected light path through the image-side surface of the first lens and the light penetrating to the next lens through this position; in addition, it can also facilitate the processing of the effective diameter edge and reduce the difficulty of surface adjustment; for the optical imaging system, it reduces the generation of stray light and ghosting, and improves the yield.

[0048] In an exemplary embodiment, the optical imaging system according to this application satisfies: -11.0 < R7 / d3s < -6.0, where D3s is the inner diameter of the object-side surface of the third spacer element, and R7 is the radius of curvature of the object-side surface of the fourth lens. More specifically, R7 and d3s can further satisfy: -10.16 < R7 / d3s < -6.50. Satisfying -11.0 < R7 / d3s < -6.0, controlling the inner diameter of the third spacer element, is beneficial for ensuring the relative illumination of the lens, blocking more excess non-imaging light rays, and ensuring lens quality; at the same time, controlling the radius of curvature of the object-side surface of the third lens also blocks reflected light rays at that location, improving image quality.

[0049] In embodiments of this application, the effective focal length f2 of the second lens of the optical imaging system can be, for example, in the range of -31.78 mm to -30.46 mm, the effective focal length f4 of the fourth lens can be, for example, in the range of -60.27 mm to -40.61 mm, the effective focal length f5 of the fifth lens can be, for example, in the range of -144.16 mm to 508.70 mm, and the effective focal length f7 of the seventh lens can be, for example, in the range of -58.41 mm to -12.10 mm.

[0050] The optical imaging system according to the above embodiments of this application can employ multiple lenses, such as the eight lenses mentioned above. By rationally allocating the optical power, surface shape, center thickness of each lens, and on-axis spacing between each lens, the low-order aberrations of the optical imaging system can be effectively balanced and controlled, while reducing its tolerance sensitivity and maintaining the miniaturization of the optical imaging system.

[0051] In embodiments of this application, at least one of the mirror surfaces of each of the first to eighth lenses is an aspherical mirror surface. An aspherical lens is characterized by a continuously changing curvature from the lens center to the lens periphery. Unlike a spherical lens, which has a constant curvature from the lens center to the lens periphery, an aspherical lens has better radius of curvature characteristics, offering advantages in improving distortion aberrations and astigmatism. By using an aspherical lens, aberrations occurring during imaging can be eliminated as much as possible, thereby improving image quality. Optionally, both the object-side and image-side surfaces of each of the first to eighth lenses are aspherical mirror surfaces.

[0052] However, those skilled in the art will understand that the number of lenses and spacers constituting the optical imaging system can be varied to obtain the various results and advantages described herein without departing from the technical solutions claimed in this application. For example, although an embodiment is described using eight lenses and eight spacers as an example, the optical imaging system is not limited to including eight lenses and eight spacers. If desired, the optical imaging system may also include other numbers of lenses and spacers.

[0053] Specific embodiments of the optical imaging system applicable to the above-described embodiments are further described below with reference to the accompanying drawings.

[0054] Example 1

[0055] The following is for reference Figures 2A to 3D The optical imaging system 1001 and optical imaging system 1002 according to Embodiment 1 of this application are described. Figure 2A and Figure 2B Schematic diagrams of the optical imaging system 1001 and optical imaging system 1002 according to Embodiment 1 of this application are shown respectively.

[0056] like Figure 2A and Figure 2B As shown, both optical imaging system 1001 and optical imaging system 1002 include a lens barrel structure P0, imaging lens groups E1 to E8, and multiple spacer elements P1 to P7b.

[0057] like Figure 2A and Figure 2BAs shown, optical imaging systems 1001 and 1002 employ the same imaging lens group. The imaging lens group of optical imaging systems 1001 and 1002, 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, a fifth lens E5, a sixth lens E6, a seventh lens E7, and an eighth lens E8. Specifically, the first lens E1 has positive optical power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens E2 has negative optical power, with its object-side surface S3 being convex and its image-side surface S4 being concave. The third lens E3 has positive optical power, with its object-side surface S5 being convex and its image-side surface S6 being concave. The fourth lens E4 has negative optical power, with its object-side surface S7 being concave and its image-side surface S8 being convex. The fifth lens E5 has negative optical power, with its object-side surface S9 being convex and its image-side surface S10 being concave. The sixth lens E6 has positive optical power, with its object-side surface S11 being concave and its image-side surface S12 being convex. The seventh lens E7 has negative optical power, with its object-side surface S13 being convex and its image-side surface S14 being concave. The eighth lens E8 has negative optical power, with its object-side surface S15 being concave and its image-side surface S16 being concave. Light from the object passes sequentially through surfaces S1 to S16 and is finally imaged onto the imaging plane (not shown).

[0058] Table 1 shows the basic parameters of the imaging lens groups of the optical imaging system 1001 and optical imaging system 1002 in Embodiment 1, wherein the units of radius of curvature, thickness / distance and focal length are all millimeters (mm).

[0059]

[0060] Table 1

[0061] In Embodiment 1, the object-side surface and image-side surface of any one of the first lens E1 to the eighth lens E8 are aspherical surfaces, and the surface shape x of each aspherical lens can be defined using, but is not limited to, the following aspherical formula:

[0062]

[0063] Where x is the distance vector from the vertex 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 reciprocal of the radius of curvature R in Table 1 above); k is the conic coefficient; Ai is the i-th order correction coefficient of the aspherical surface. Tables 2-1 and 2-2 give the higher-order coefficients A4, A6, A8, A16, A27, A18, A19 ... 10 A 12 A 14 A 16 A 18 A 20 A22 A 24 A 26 A 28 and A 30 .

[0064]

[0065]

[0066] Table 2-1

[0067] Face number A18 A20 A22 A24 A26 A28 A30 S1 -1.7085E-05 -6.7130E-06 -6.4029E-07 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S2 -3.9796E-05 -1.3749E-05 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S3 -2.5144E-05 -9.8653E-06 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S4 -2.8054E-06 -4.9904E-06 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S5 1.6106E-05 5.8834E-06 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S6 2.6376E-05 8.5630E-06 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S7 1.4835E-06 -1.2511E-05 -5.2960E-06 -1.6476E-06 0.0000E+00 0.0000E+00 0.0000E+00 S8 -3.3742E-06 -2.7874E-05 -1.5675E-05 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S9 5.5004E-04 1.1897E-04 4.1482E-05 -9.5287E-06 0.0000E+00 0.0000E+00 0.0000E+00 S10 7.7115E-04 2.0059E-05 -3.0295E-05 -5.2352E-05 -1.4195E-06 0.0000E+00 0.0000E+00 S11 9.6722E-04 5.3953E-04 3.2438E-04 -1.4630E-04 -7.3553E-06 0.0000E+00 0.0000E+00 S12 3.8781E-04 4.3537E-04 2.5210E-04 1.2412E-04 4.7143E-05 0.0000E+00 0.0000E+00 S13 -1.1837E-03 1.9084E-03 -3.7027E-04 -1.3456E-03 -6.4623E-04 1.1977E-04 -5.9765E-06 S14 -1.8601E-03 -8.0838E-04 1.8379E-03 -4.3467E-05 2.0778E-04 -1.0475E-04 -9.7776E-05 S15 -2.7874E-03 -6.3988E-03 7.1306E-03 -2.8884E-03 3.3785E-04 3.7716E-04 -1.9101E-04 S16 7.7750E-03 -3.8620E-03 3.0945E-03 -2.6330E-03 7.8582E-04 -1.6989E-04 2.6048E-04

[0068] Table 2-2

[0069] like Figure 2A and Figure 2B As shown, both optical imaging system 1001 and optical imaging system 1002 include eight spacer elements, namely, first spacer element P1, second spacer element P2, third spacer element P3, fourth spacer element P4, fifth spacer element P5, sixth spacer element P6, seventh spacer element P7 and eighth spacer element P7b. The first spacer element P1 is disposed between the first lens E1 and the second lens E2 and is in contact with the image side of the first lens E1; the second spacer element P2 is disposed between the second lens E2 and the third lens E3 and is in contact with the image side of the second lens E2; the third spacer element P3 is disposed between the third lens E3 and the fourth lens E4 and is in contact with the image side of the third lens E3; the fourth spacer element P4 is disposed between the fourth lens E4 and the fifth lens E5 and is in contact with the image side of the fourth lens E4; the fifth spacer element P5 is disposed between the fifth lens E5 and the sixth lens E6 and is in contact with the image side of the fifth lens E5; the sixth spacer element P6 is disposed between the sixth lens E6 and the seventh lens E7 and is in contact with the image side of the sixth lens E6; the seventh spacer element P7 and the eighth spacer element P7b are disposed between the seventh lens E7 and the eighth lens E8, with the seventh spacer element P7 in contact with the image side of the seventh lens E7 and the eighth spacer element P7b in contact with the object side of the eighth lens E8. In this embodiment, the first spacer element P1, the second spacer element P2, the third spacer element P3, the fourth spacer element P4, the fifth spacer element P5, the sixth spacer element P6, and the eighth spacer element P7b are spacers, and the seventh spacer element P7 is a spacer ring. The aforementioned spacers P1 to P7b can block excess external light from entering, allowing the lens to better support the lens barrel, and enhancing the structural stability of the optical imaging system 1001 and the optical imaging system 1002.

[0070] The difference between optical imaging systems 1001 and 1002 lies in the different structural dimensions of the eight spacer elements they include. Table 3 shows the basic parameters of the spacer elements and lens barrel of optical imaging systems 1001 and 1002 in Embodiment 1. As an example, both optical imaging systems 1001 and 1002 have a lens barrel P0, and the outer diameter D0m of the image-side surface of lens barrel P0 is 16.75 mm.

[0071] Example parameters Optical Imaging System 1001 Optical Imaging System 1002 D5s(mm) 10.40 9.80 EP34(mm) 0.51 0.49 D3m(mm) 7.60 5.67 D5m (mm) 10.40 9.80 EP45(mm) 0.49 0.45 D4m(mm) 8.20 6.10 D6m (mm) 11.40 10.80 CP5 (mm) 0.02 0.02 CP7 (mm) 0.43 0.46 D0m(mm) 16.75 16.75 CP2 (mm) 0.02 0.02 D1s(mm) 6.40 5.01 D2s(mm) 7.00 5.30 d3s(mm) 3.49 3.64 CP4 (mm) 0.02 0.02

[0072] Table 3

[0073] Figure 3A The on-axis chromatic aberration curves of optical imaging systems 1001 and 1002 of Embodiment 1 are shown, which represent the deviation of the focal point of light of different wavelengths after passing through the lens. Figure 3B Astigmatism curves of optical imaging systems 1001 and 1002 of Embodiment 1 are shown, representing meridional image plane curvature and sagittal image plane curvature. Figure 3C The distortion curves of optical imaging systems 1001 and 1002 of Embodiment 1 are shown, representing the distortion magnitude values ​​corresponding to different image heights. Figure 3D The magnification chromatic aberration curves of optical imaging systems 1001 and 1002 of Embodiment 1 are shown, representing the deviations in image height at different points on the imaging plane after light passes through the lens. According to... Figures 3A to 3D It can be seen that the optical imaging system 1001 and optical imaging system 1002 given in Example 1 can achieve good imaging quality.

[0074] Example 2

[0075] The following is for reference Figures 4A to 5D The optical imaging system 2001 and optical imaging system 2002 according to Embodiment 2 of this application are described. In this embodiment and the following embodiments, for the sake of brevity, some descriptions similar to those in Embodiment 1 will be omitted. Figures 4A to 4B Schematic diagrams of the optical imaging system 2001 and optical imaging system 2002 according to Embodiment 2 of this application are shown respectively.

[0076] like Figure 4A and Figure 4B As shown, both optical imaging system 2001 and optical imaging system 2002 include a lens barrel structure P0, imaging lens groups E1 to E8, and multiple spacer elements P1 to P7b.

[0077] like Figure 4A and Figure 4BAs shown, optical imaging systems 2001 and 2002 employ the same imaging lens group. The imaging lens group of optical imaging systems 2001 and 2002, 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, a fifth lens E5, a sixth lens E6, a seventh lens E7, and an eighth lens E8. Specifically, the first lens E1 has positive optical power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens E2 has negative optical power, with its object-side surface S3 being convex and its image-side surface S4 being concave. The third lens E3 has positive optical power, with its object-side surface S5 being convex and its image-side surface S6 being concave. The fourth lens E4 has negative optical power, with its object-side surface S7 being concave and its image-side surface S8 being convex. The fifth lens E5 has positive optical power, with its object-side surface S9 being convex and its image-side surface S10 being concave. The sixth lens E6 has positive optical power, with its object-side surface S11 being concave and its image-side surface S12 being convex. The seventh lens E7 has negative optical power, with its object-side surface S13 being convex and its image-side surface S14 being concave. The eighth lens E8 has negative optical power, with its object-side surface S15 being concave and its image-side surface S16 being concave. Light from the object passes sequentially through surfaces S1 to S18 and is finally imaged onto the imaging plane (not shown).

[0078] Table 4 shows the basic parameters of the imaging lens groups of optical imaging systems 2001 and 2002 in Embodiment 2, wherein the units of radius of curvature, thickness / distance and focal length are millimeters (mm). Tables 5-1 and 5-2 show the higher-order coefficients that can be used for each aspherical mirror in Embodiment 2, wherein each aspherical surface shape can be defined by formula (1) given in Embodiment 1 above.

[0079]

[0080]

[0081] Table 4

[0082] Face number A4 A6 A8 A10 A12 A14 A16 S1 3.3616E-02 1.8808E-03 -1.5603E-03 -1.1275E-03 -5.0339E-04 -2.1709E-04 -7.3183E-05 S2 9.4833E-03 4.5433E-03 1.2261E-03 2.2087E-04 -9.2143E-05 -1.3245E-04 -9.4178E-05 S3 -6.7260E-02 2.2324E-02 3.4767E-03 5.4959E-04 1.3671E-04 -5.0653E-05 -5.2457E-05 S4 -1.5339E-02 1.2153E-02 1.8688E-03 5.8347E-05 8.5127E-05 1.1516E-05 6.2287E-06 S5 5.0051E-02 -2.2870E-04 1.5893E-03 4.8836E-04 2.1687E-04 9.9331E-05 4.0039E-05 S6 -1.4726E-02 -3.4076E-03 -3.0624E-04 2.6742E-04 1.2915E-04 9.3313E-05 3.4206E-05 S7 -2.6427E-01 -2.3550E-02 -4.2671E-03 -6.0240E-04 -2.2097E-04 -4.2922E-05 1.6834E-06 S8 -3.2791E-01 3.4010E-03 5.7003E-03 4.3422E-03 1.1489E-03 5.9374E-04 1.5795E-04 S9 -7.3522E-01 9.7034E-03 -1.2238E-02 3.7212E-03 -2.8282E-04 1.0306E-03 6.6465E-04 S10 -1.0259E+00 9.5235E-02 1.8715E-02 5.4615E-03 -4.8951E-03 -1.6113E-03 4.6949E-05 S11 -5.7627E-01 -2.6081E-01 1.3595E-01 3.4457E-02 4.1145E-03 -5.7729E-03 -5.0582E-03 S12 1.3295E+00 -1.3945E-01 1.8671E-01 -4.4347E-02 2.0344E-02 6.8512E-03 3.4114E-03 S13 -4.6654E+00 2.9241E-01 1.1959E-01 -7.0426E-02 8.0264E-03 -8.7258E-03 -5.9797E-03 S14 -4.8565E+00 7.2025E-01 3.7468E-02 -2.4085E-02 1.7180E-02 6.5323E-03 -5.9161E-03 S15 -5.0158E-02 1.1707E+00 -6.9951E-01 2.8075E-01 -6.2682E-02 -1.5690E-02 1.5442E-02 S16 -6.8676E+00 1.3861E+00 -4.2175E-01 2.3801E-01 -1.0602E-01 3.9118E-03 -9.8500E-03

[0083] Table 5-1

[0084] Face number A18 A20 A22 A24 A26 A28 A30 S1 -2.8926E-05 -2.9004E-06 3.5119E-07 3.3327E-06 -3.3815E-07 -7.4562E-07 -2.0395E-06 S2 -5.0611E-05 -2.0685E-05 -1.7598E-06 5.2783E-06 7.0819E-06 4.2225E-06 1.4892E-06 S3 -2.6310E-05 -1.1029E-05 -1.3107E-06 2.8603E-07 1.5736E-06 1.7376E-06 1.8535E-06 S4 -2.6685E-06 1.6098E-06 1.7052E-06 4.1229E-06 1.6847E-06 -7.1309E-07 -3.0389E-06 S5 1.4810E-05 3.9667E-06 4.7292E-06 4.0574E-06 5.6271E-06 4.8296E-06 4.4245E-06 S6 2.4124E-05 4.0125E-06 3.2310E-06 1.0547E-06 1.3187E-06 1.4419E-06 1.2949E-06 S7 -1.5771E-05 4.4331E-06 -6.9904E-06 3.5273E-06 -2.5871E-06 2.3249E-06 6.1852E-07 S8 4.1502E-05 -1.9566E-07 -1.2802E-05 -6.0622E-06 -1.1024E-05 -3.5745E-06 -5.0219E-06 S9 6.2072E-04 8.6532E-05 2.5301E-05 -6.3550E-05 -1.7152E-05 -2.4841E-05 -3.9152E-06 S10 5.1590E-04 -8.0916E-05 -7.4757E-05 -3.4530E-05 3.2960E-05 1.3380E-05 -5.8395E-06 S11 -2.1796E-04 4.0373E-04 3.3738E-04 -1.3293E-04 -6.6187E-05 2.0832E-05 8.5673E-06 S12 8.4353E-05 1.1043E-03 -8.4387E-05 -2.2621E-04 -4.5996E-05 8.8027E-05 -1.1849E-04 S13 -1.8144E-03 1.6335E-03 5.7285E-04 -5.7258E-04 -4.1716E-04 2.4388E-04 -7.0239E-05 S14 -1.3152E-03 -1.9622E-03 9.9051E-04 -3.3253E-04 2.3504E-04 4.0324E-05 -1.1219E-04 S15 1.1594E-04 -7.6497E-03 5.6744E-03 -1.8599E-03 -6.5337E-05 2.9647E-04 -7.7662E-05 S16 7.0698E-03 -3.0327E-03 2.8233E-03 -2.8457E-03 7.5041E-04 -4.6007E-04 2.6328E-04

[0085] Table 5-2

[0086] like Figure 4A and Figure 4BAs shown, both optical imaging systems 2001 and 2002 include eight spacer elements, namely, the first spacer element P1, the second spacer element P2, the third spacer element P3, the fourth spacer element P4, the fifth spacer element P5, the sixth spacer element P6, the seventh spacer element P7, and the eighth spacer element P7b. The positions of these eight spacer elements are the same as those of the spacer elements in optical imaging systems 1001 and 1002 of Embodiment 1, and will not be described again.

[0087] The difference between optical imaging system 2001 and optical imaging system 2002 lies in the different structural dimensions of the eight spacer elements included. Table 6 shows the basic parameters of the spacer elements and lens barrel of optical imaging system 2001 and optical imaging system 2002 in Embodiment 2. As an example, both optical imaging system 2001 and optical imaging system 2002 have a lens barrel P0, and the outer diameter D0m of the image side of lens barrel P0 is 16.05 mm.

[0088] Example parameters Optical Imaging System 2001 Optical Imaging System 2002 D5s(mm) 10.20 10.00 EP34(mm) 0.57 0.51 D3m(mm) 7.40 5.35 D5m (mm) 10.20 10.00 EP45(mm) 0.51 0.58 D4m(mm) 8.00 5.62 D6m (mm) 11.20 11.00 CP5 (mm) 0.02 0.02 CP7 (mm) 0.53 0.40 D0m(mm) 16.05 16.05 CP2 (mm) 0.02 0.02 D1s(mm) 6.20 5.00 D2s(mm) 6.80 5.16 d3s(mm) 3.60 4.20 CP4 (mm) 0.02 0.02

[0089] Table 6

[0090] Figure 5A The on-axis chromatic aberration curves of optical imaging systems 2001 and 2002 of Embodiment 2 are shown, which represent the deviation of the focal point of light of different wavelengths after passing through the lens. Figure 5B Astigmatism curves of optical imaging systems 2001 and 2002 of Embodiment 2 are shown, representing meridional image plane curvature and sagittal image plane curvature. Figure 5C The distortion curves of optical imaging systems 2001 and 2002 of Embodiment 2 are shown, which represent the distortion magnitude values ​​corresponding to different image heights. Figure 5D The magnification chromatic aberration curves of optical imaging systems 2001 and 2002 of Embodiment 2 are shown, representing the deviations in image height at different points on the imaging plane after light passes through the lens. According to... Figures 5A to 5D It can be seen that the optical imaging system 2001 and optical imaging system 2002 given in Example 2 can achieve good imaging quality.

[0091] Example 3

[0092] The following is for reference Figures 6A to 7D The optical imaging system 3001 and optical imaging system 3002 according to Embodiment 3 of this application are described. Figures 6A to 6B Schematic diagrams of the optical imaging system 3001 and optical imaging system 3002 according to Embodiment 3 of this application are shown respectively.

[0093] like Figure 6A and Figure 6B As shown, both optical imaging system 3001 and optical imaging system 3002 include a lens barrel structure P0, imaging lens groups E1 to E8, and multiple spacer elements P1 to P7b.

[0094] like Figure 6A and Figure 6B As shown, optical imaging systems 3001 and 3002 employ the same imaging lens group. The imaging lens group of optical imaging systems 3001 and 3002, 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, a fifth lens E5, a sixth lens E6, a seventh lens E7, and an eighth lens E8. Specifically, the first lens E1 has positive optical power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens E2 has negative optical power, with its object-side surface S3 being convex and its image-side surface S4 being concave. The third lens E3 has positive optical power, with its object-side surface S5 being convex and its image-side surface S6 being concave. The fourth lens E4 has negative optical power, with its object-side surface S7 being concave and its image-side surface S8 being convex. The fifth lens E5 has negative optical power, with its object-side surface S9 being concave and its image-side surface S10 being concave. The sixth lens E6 has positive optical power, with its object-side surface S11 being concave and its image-side surface S12 being convex. The seventh lens E7 has negative optical power, with its object-side surface S13 being convex and its image-side surface S14 being concave. The eighth lens E8 has negative optical power, with its object-side surface S15 being concave and its image-side surface S16 being concave. Light from the object passes sequentially through surfaces S1 to S18 and is finally imaged onto the imaging plane (not shown).

[0095] Table 7 shows the basic parameters of the imaging lens groups of optical imaging systems 3001 and 3002 in Embodiment 3, wherein the units of radius of curvature, thickness / distance and focal length are millimeters (mm). Tables 8-1 and 8-2 show the higher-order coefficients that can be used for each aspherical mirror in Embodiment 3, wherein each aspherical surface shape can be defined by formula (1) given in Embodiment 1 above.

[0096]

[0097] Table 7

[0098]

[0099]

[0100] Table 8-1

[0101] Face number A18 A20 A22 A24 A26 A28 A30 S1 -1.2591E-05 -1.2402E-05 -2.2121E-06 -4.7166E-06 9.0080E-07 -3.0080E-06 2.2105E-06 S2 -2.3851E-05 -1.2094E-05 -3.9534E-06 -1.1159E-06 2.3418E-06 1.6275E-06 1.1752E-06 S3 -1.4994E-05 -6.9938E-06 -2.2437E-06 2.9655E-07 2.6664E-06 2.3993E-06 1.1718E-06 S4 -3.3265E-05 -1.1993E-05 -4.4981E-06 -4.9468E-07 -4.7888E-07 7.0607E-07 1.0766E-06 S5 -3.3527E-05 -1.5566E-05 -6.3400E-06 -3.4232E-06 -1.1999E-06 -3.5163E-06 -2.4421E-06 S6 -5.9936E-05 -4.7785E-05 -1.8606E-05 -1.3841E-05 -1.3854E-06 -1.0902E-06 3.4220E-06 S7 -7.8390E-05 -6.0298E-05 -3.0787E-05 -2.1719E-05 -1.1278E-05 -5.5328E-06 -3.0913E-07 S8 2.2924E-04 5.4792E-05 1.7092E-06 -1.2887E-05 -2.1487E-05 -1.5802E-05 -1.2095E-05 S9 1.0823E-03 4.6900E-04 2.5467E-04 5.3063E-05 -1.2996E-05 -2.0366E-05 -2.2589E-05 S10 -8.4201E-04 -9.9124E-05 6.2803E-04 1.4126E-04 5.4734E-05 -3.6014E-05 -1.2385E-05 S11 2.7288E-03 2.7181E-03 2.5527E-03 -7.8116E-04 -3.2742E-04 -2.8376E-04 1.0844E-04 S12 -3.5529E-03 -2.3500E-03 -2.0674E-03 -8.0442E-04 7.7060E-05 1.4647E-04 1.3809E-04 S13 -1.6566E-02 6.0380E-03 -1.6494E-04 -2.1316E-04 -2.4469E-04 4.1070E-04 -2.7455E-04 S14 1.4136E-03 8.1647E-04 -1.3757E-03 -2.0429E-03 -1.4965E-04 5.7594E-05 3.2054E-04 S15 -5.5978E-03 -1.3716E-03 2.7360E-03 -1.1678E-03 2.9898E-04 8.7979E-05 -2.7578E-05 S16 9.9383E-04 -1.0949E-03 1.5897E-03 3.4945E-04 2.2749E-04 -5.5026E-04 5.0377E-04

[0102] Table 8-2

[0103] like Figure 6A and Figure 6B As shown, both optical imaging systems 3001 and 3002 include eight spacer elements, namely, the first spacer element P1, the second spacer element P2, the third spacer element P3, the fourth spacer element P4, the fifth spacer element P5, the sixth spacer element P6, the seventh spacer element P7, and the eighth spacer element P7b. The positions of these eight spacer elements are the same as those of the spacer elements in optical imaging systems 1001 and 1002 of Embodiment 1, and will not be described again.

[0104] The difference between optical imaging systems 3001 and 3002 lies in the different structural dimensions of the eight spacer elements they include. Table 9 shows the basic parameters of the spacer elements and lens barrel of optical imaging systems 3001 and 3002 in Embodiment 3. As an example, both optical imaging systems 3001 and 3002 have a lens barrel P0, and the outer diameter D0m of the image-side surface of lens barrel P0 is 16.49 mm.

[0105] Example parameters Optical Imaging System 3001 Optical Imaging System 3002 D5s(mm) 10.80 10.60 EP34(mm) 0.45 0.43 D3m(mm) 8.00 5.59 D5m (mm) 10.80 10.60 EP45(mm) 0.54 0.56 D4m(mm) 8.60 5.84 D6m (mm) 11.80 11.50 CP5 (mm) 0.02 0.02 CP7 (mm) 0.45 0.42 D0m(mm) 16.49 16.49 CP2(mm) 0.02 0.02 D1s(mm) 6.80 5.22 D2s(mm) 7.40 5.42 d3s(mm) 3.56 3.83 CP4 (mm) 0.02 0.02

[0106] Table 9

[0107] Figure 7A The on-axis chromatic aberration curves of optical imaging systems 3001 and 3002 of Embodiment 3 are shown, which represent the deviation of the focal point of light of different wavelengths after passing through the lens. Figure 7B Astigmatism curves of optical imaging systems 3001 and 3002 of Embodiment 3 are shown, representing meridional image plane curvature and sagittal image plane curvature. Figure 7C The distortion curves of optical imaging systems 3001 and 3002 of Embodiment 3 are shown, which represent the distortion magnitude values ​​corresponding to different image heights. Figure 7D The magnification chromatic aberration curves of optical imaging systems 3001 and 3002 of Embodiment 3 are shown, representing the deviation of different image heights on the imaging plane after light passes through the lens. According to Figures 7A to 7D It can be seen that the optical imaging system 3001 and optical imaging system 3002 given in Example 3 can achieve good imaging quality.

[0108] In summary, the optical imaging systems 1001, 1002, 2001, 2002, 3001 and 1003 of Examples 1 to 3 satisfy the relationships shown in Table 10.

[0109] Conditional / Optical Imaging System 1001 1002 2001 2002 3001 3002 (f4+D5s+D3m) / EP34 -70.18 -78.28 -40.24 -50.03 -92.55 -102.98 R11 / (CP4+T45+EP45) -14.47 -15.09 -14.00 -13.09 -18.85 -18.41 f5 / (D4m+D5m+D6m) -4.80 -5.40 17.30 19.11 -1.27 -1.42 f7 / (CP5+T56+CP7) -50.56 -49.28 -43.42 -48.28 -12.04 -12.41 R9 / D0m 0.79 0.79 0.74 0.74 -2.77 -2.77 R10 / (CT2+CP2+T23+CT3) 11.86 11.86 13.37 13.37 70.80 70.80 f2 / D2s+D2s / R4 -3.36 -5.10 -3.46 -5.21 -2.82 -4.67 f5 / f7+D1s / R1 4.75 4.25 -6.86 -7.28 5.71 5.14 R7 / d3s -9.58 -9.19 -7.61 -6.51 -10.15 -9.44

[0110] Table 10

[0111] The above description is merely a preferred embodiment of this application and an explanation 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 technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above 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: An imaging lens group 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 sequentially along the optical axis from the object side to the image side; and Multiple spacer elements, including a fourth spacer element located between the fourth lens and the fifth lens and in contact with the image side of the fourth lens, a fifth spacer element located between the fifth lens and the sixth lens and in contact with the image side of the fifth lens, and a sixth spacer element located between the sixth lens and the seventh lens and in contact with the image side of the sixth lens; in, The effective focal length f5 of the fifth lens, the outer diameter D4m of the image side of the fourth spacer element, the outer diameter D5m of the image side of the fifth spacer element, and the outer diameter D6m of the image side of the sixth spacer element satisfy: -5.41 < f5 / (D4m+D5m+D6m) < 19.12; The optical imaging system further includes a lens barrel for accommodating the imaging lens group and the plurality of spacer elements, wherein the outer diameter D0m of the image-side end of the lens barrel and the radius of curvature R9 of the object-side surface of the fifth lens satisfy: -2.78 < R9 / D0m < 0.

80. The first lens has positive optical power, and the radii of curvature of both its object-side and image-side surfaces are positive. The second lens has negative optical power, and its object-side radius of curvature is positive, as is its image-side radius of curvature. The third lens has positive optical power, and its object-side radius of curvature is positive, as is its image-side radius of curvature. The fourth lens has negative optical power, and the radii of curvature of both its object-side and image-side surfaces are negative. The radius of curvature of the image-side surface of the fifth lens is positive; The sixth lens has positive optical power, and its object-side radius of curvature is negative, as is its image-side radius of curvature. The seventh lens has negative optical power, a positive radius of curvature on its object-side surface, and a positive radius of curvature on its image-side surface; and The eighth lens has negative optical power, and its object-side radius of curvature is negative while its image-side radius of curvature is positive. The optical imaging system has eight lenses with optical power.

2. The optical imaging system according to claim 1, characterized in that, The maximum thickness CP4 of the fourth spacer element, the spacing EP45 between the fourth and fifth spacers along the optical axis, the air gap T45 between the fourth and fifth lenses on the optical axis, and the radius of curvature R11 of the object side surface of the sixth lens satisfy: -18.86 < R11 / (CP4 + T45 + EP45) < -13.

08.

3. The optical imaging system according to claim 1, characterized in that, The plurality of spacers also includes a seventh spacer located between the seventh lens and the eighth lens and in contact with the image side of the seventh lens. The maximum thickness CP5 of the fifth spacer, the maximum thickness CP7 of the seventh spacer, the effective focal length f7 of the seventh lens, and the air gap T56 between the fifth lens and the sixth lens on the optical axis satisfy: -50.57 < f7 / (CP5+T56+CP7) < -12.

03.

4. The optical imaging system according to claim 1, characterized in that, The plurality of spacers further includes a second spacer located between the second lens and the third lens and in contact with the image-side surface of the second lens. The radius of curvature R10 of the image-side surface of the fifth lens, the maximum thickness CP2 of the second spacer, the center thickness CT2 of the second lens on the optical axis, the center thickness CT3 of the third lens on the optical axis, and the air gap T23 between the second lens and the third lens on the optical axis satisfy: 11.85 < R10 / (CT2 + CP2 + T23 + CT3) < 70.

81.

5. The optical imaging system according to claim 1, characterized in that, The plurality of spacers also includes a second spacer located between the second lens and the third lens and in contact with the image side of the second lens. The outer diameter D2s of the object side of the second spacer, the radius of curvature R4 of the image side of the second lens and the effective focal length f2 of the second lens satisfy: -5.22<f2 / D2s+D2s / R4<-2.

81.

6. The optical imaging system according to claim 1, characterized in that, The plurality of spacers also includes a first spacer located between the first lens and the second lens and in contact with the image side of the first lens. The outer diameter D1s of the object side of the first spacer, the radius of curvature R1 of the object side of the first lens, the effective focal length f5 of the fifth lens and the effective focal length f7 of the seventh lens satisfy: -7.29 < f5 / f7 + D1s / R1 < 5.

72.

7. The optical imaging system according to claim 1, characterized in that, The plurality of spacers also includes a third spacer located between the third lens and the fourth lens and in contact with the image side of the third lens, wherein the inner diameter D3s of the object side of the third spacer and the radius of curvature R7 of the object side of the fourth lens satisfy: -10.16 < R7 / d3s < -6.

50.

8. The optical imaging system according to claim 1, characterized in that, The plurality of spacers also includes a third spacer located between the third lens and the fourth lens and in contact with the image side of the third lens. The outer diameter D3m of the image side of the third spacer, the outer diameter D5s of the object side of the fifth spacer, the spacing EP34 between the third spacer and the fourth spacer along the optical axis and the effective focal length f4 of the fourth lens satisfy: -102.99 < (f4 + D5s + D3m) / EP34 < -40.23.

Images