Optical imaging system

Abstract

The application discloses an optical imaging system, which comprises: a lens group sequentially comprising, from an object side to an image side along an optical axis, a first lens with positive refractive power, a second lens with negative refractive power, a third lens with negative refractive power, a fourth lens with refractive power, a fifth lens with positive refractive power, a sixth lens with positive refractive power, and a seventh lens with negative refractive power, wherein the second lens is a meniscus lens; a plurality of spacer elements, comprising a fifth spacer element at least partially in contact with an image side surface of the fifth lens and a sixth spacer element at least partially in contact with an image side surface of the sixth lens; and a lens barrel for accommodating the lens group and the plurality of spacer elements; wherein the effective focal length f of the optical imaging system, the maximum half field angle Semi-FOV of the optical imaging system, the inner diameter d6m of the image side surface of the sixth spacer element, and the inner diameter d5m of the image side surface of the fifth spacer element satisfy: 2.5 < f x tan (Semi-FOV) / (d6m-d5m) < 11.5.

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 rapid development of portable smart devices, the consumer market has placed greater demands on the photography capabilities of these devices, especially the rear main camera lens, which is used frequently and requires high image quality. Therefore, to improve image quality, the number of lenses in the rear main camera lens is gradually increasing. Correspondingly, the difficulty of lens molding and lens assembly is also increasing.

[0003] For multi-element imaging lenses, the reduced space ratio of individual lenses and the miniaturization of modules increase the design difficulty. When the lens barrel and spacer elements of the imaging lens are not designed properly, problems such as poor optical transmission, unreasonable spatial arrangement, and severe stray light can easily occur, thus affecting the overall quality of the lens. Therefore, how to enable an optical imaging system to have good optical performance with a large image plane, long back focal length, and low stray light while ensuring structural stability is one of the key research topics for designers in this field. Summary of the Invention

[0004] This application provides an optical imaging system comprising: a lens group, sequentially comprising along the optical axis from the object side to the image side: a first lens with positive optical power, a second lens with negative optical power, a third lens with negative optical power, a fourth lens with optical power, a fifth lens with positive optical power, a sixth lens with positive optical power, and a seventh lens with negative optical power, wherein the second lens is a meniscus lens; a plurality of spacer elements, including a fifth spacer element that at least partially contacts the image-side surface of the fifth lens and a sixth spacer element that at least partially contacts the image-side surface of the sixth lens; and a lens barrel for accommodating the lens group and the plurality of spacer elements; wherein the effective focal length f of the optical imaging system, the maximum semi-field of view (Semi-FOV) of the optical imaging system, the inner diameter d6m of the image-side surface of the sixth spacer element, and the inner diameter d5m of the image-side surface of the fifth spacer element satisfy: 2.5 <f×tan(Semi-FOV) / (d6m-d5m)<11.5。

[0005] In one embodiment, the radius of curvature R10 of the image-side surface of the fifth lens and the radius of curvature R11 of the object-side surface of the sixth lens satisfy: -7.5 <R10 / R11<-1.5。

[0006] In one embodiment, the plurality of spacers further includes a second spacer element that is at least partially in contact with the image-side surface of the second lens and a third spacer element that is at least partially in contact with the image-side surface of the third lens.

[0007] In one embodiment, at least one of the plurality of spacer elements has the same inner diameter on the object side and the same outer diameter on the image side.

[0008] In one embodiment, the plurality of spacer elements further includes a second spacer element that at least partially contacts the image-side surface of the second lens and a third spacer element that at least partially contacts the image-side surface of the third lens; wherein, the inner diameter d3m of the image-side surface of the third spacer element, the air gap T34 between the third and fourth lenses on the optical axis, the outer diameter D2s of the object-side surface of the second spacer element, and the air gap T23 between the second and third lenses on the optical axis satisfy: 32.0 <d3m / T34+D2s / T23<125.5。

[0009] In one embodiment, the plurality of spacers further includes a first spacer element that is at least partially in contact with the image side of the first lens; wherein the outer diameter D1s of the object side of the first spacer element, the inner diameter d1m of the image side of the first spacer element, the maximum thickness CP1 of the first spacer element along the optical axis, the air gap T12 between the first lens and the second lens on the optical axis, and the center thickness CT2 of the second lens on the optical axis satisfy: 1.0 < (D1s-d1m) / (CP1-T12+CT2) < 6.5.

[0010] In one embodiment, the plurality of spacers further includes a first spacer element that is at least partially in contact with the image side of the first lens and a second spacer element that is at least partially in contact with the image side of the second lens; wherein the outer diameter D2s of the object side of the second spacer element, the outer diameter D1m of the image side of the first spacer element, the radius of curvature R1 of the object side of the first lens and the radius of curvature R3 of the object side of the second lens satisfy: 7.5 < (D2s + D1m) / (R1 - R3) < 16.0.

[0011] In one embodiment, the plurality of spacers further includes a fourth spacer element that is at least partially in contact with the image side of the fourth lens, wherein the center thickness CT4 of the fourth lens on the optical axis, the center thickness CT5 of the fifth lens on the optical axis, the maximum thickness CP4 of the fourth spacer element along the optical axis and the maximum thickness CP5 of the fifth spacer element along the optical axis satisfy: 1.0 < (CT4 + CT5) / (CP4 + CP5) < 55.5.

[0012] In one embodiment, the plurality of spacers further includes a first spacer element that is at least partially in contact with the image side of the first lens; wherein the outer diameter D6s of the object side of the sixth spacer element, the inner diameter d1s of the object side of the first spacer element, the radius of curvature R1 of the object side of the first lens, and the radius of curvature R11 of the object side of the sixth lens satisfy: 4.5 < (D6s + d1s) / (R1 + R11) < 9.5.

[0013] In one embodiment, the plurality of spacers further includes a first spacer element that at least partially contacts the image-side surface of the first lens, a second spacer element that at least partially contacts the image-side surface of the second lens, a third spacer element that at least partially contacts the image-side surface of the third lens, and a fourth spacer element that at least partially contacts the image-side surface of the fourth lens; wherein the effective focal length f of the optical imaging system, the combined focal length f56 of the fifth and sixth lenses, the spacing EP36 between the third and sixth spacers along the optical axis, and the sum of the maximum thicknesses ∑CP of the first to sixth spacers along the optical axis satisfy: 3.5 < (f + f56) / (EP36 - ∑CP) < 15.5.

[0014] In one embodiment, the plurality of spacers further includes a fourth spacer element that is at least partially in contact with the image-side surface of the fourth lens, wherein the outer diameter D4m of the image-side surface of the fourth spacer element, the inner diameter d4s of the object-side surface of the fourth spacer element, the radius of curvature R9 of the object-side surface of the fifth lens, and the radius of curvature R8 of the image-side surface of the fourth lens satisfy: 0 <D4m / R9+d4s / R8<6.0。

[0015] In one embodiment, the plurality of spacers further includes a fourth spacer element that is at least partially in contact with the image-side surface of the fourth lens; wherein the inner diameter d4s of the object-side surface of the fourth spacer element, the inner diameter d5m of the image-side surface of the fifth spacer element, the radius of curvature R9 of the object-side surface of the fifth lens, and the radius of curvature R11 of the object-side surface of the sixth spacer element satisfy: -41.5<(d4s-d5m) / (R9+R11)<12.5.

[0016] In one embodiment, the plurality of spacers further includes a fourth spacer element that is at least partially in contact with the image side of the fourth lens; wherein the effective focal length f5 of the fifth lens, the effective focal length f7 of the seventh lens, the spacing EP45 between the fourth and fifth spacers on the optical axis, and the spacing EP56 between the fifth and sixth spacers on the optical axis satisfy: 4.0 < (f5-f7) / (EP45+EP56) < 12.5.

[0017] In one embodiment, the plurality of spacers further includes a first spacer element that at least partially contacts the image-side surface of the first lens, a second spacer element that at least partially contacts the image-side surface of the second lens, a third spacer element that at least partially contacts the image-side surface of the third lens, and a fourth spacer element that at least partially contacts the image-side surface of the fourth lens; wherein the maximum height L of the lens barrel along the optical axis, the distance TD from the object-side surface of the first lens to the image-side surface of the seventh lens along the optical axis, the sum of the air gaps ∑AT between any two adjacent lenses from the first lens to the seventh lens along the optical axis, and the sum of the maximum thicknesses ∑CP of the first spacer element to the sixth spacer element along the optical axis satisfy: 4.5 < (L + TD) / (∑AT - ∑CP) < 14.5.

[0018] In one embodiment, the inner diameter d5m of the image side of the fifth spacer element, the inner diameter d6m of the image side of the sixth spacer element, the center thickness CT5 of the fifth lens on the optical axis, and the center thickness CT6 of the sixth lens on the optical axis satisfy: 5.5 < (d5m + d6m) / (CT5 + CT6) < 11.5.

[0019] In one embodiment, the plurality of spacers further includes a fourth spacer element that is at least partially in contact with the image-side surface of the fourth lens, wherein the outer diameter D4m of the image-side surface of the fourth spacer element, the inner diameter d4s of the object-side surface of the fourth spacer element, the center thickness CT4 of the fourth lens on the optical axis, and the air gap T45 between the fourth lens and the fifth lens on the optical axis satisfy: 0.5 < (D4m - d4s) / (CT4 - T45) < 6.0.

[0020] In one embodiment, the effective focal length f of the optical imaging system, the aperture number Fno of the optical imaging system, the outer diameter D0m of the image-side end of the lens barrel near the image side, and the inner diameter d0m of the image-side end of the lens barrel near the image side satisfy: 10.5 <f×Fno / (D0m-d0m)<44.5。

[0021] In one embodiment, the maximum height L of the lens barrel along the optical axis, the distance TD from the object side of the first lens to the image side of the seventh lens on the optical axis, the outer diameter D0m of the lens barrel near the image side end, the distance TTL from the object side of the first lens to the imaging surface of the optical imaging system on the optical axis, and the sum of the center thicknesses of the first lens to the seventh lens on the optical axis, ∑CT, satisfy: 5.0 < (L-D0m) / (BFL-∑CT) < 19.5.

[0022] The optical imaging system provided in this application includes multiple lenses, multiple spacer elements, and a lens barrel. By controlling the optical power of each lens and the surface shape of the second lens, the optical imaging system achieves good optical performance with a large image plane and a long back focal length. The reasonable placement of spacer elements between the lenses helps to enhance the stability of the lens and facilitates the subsequent adjustment of the lens MTF performance. At the same time, it effectively absorbs excess light after refraction through the lens and reduces stray light. By constraining the aperture difference between the fifth and sixth spacer elements, the optical imaging system of this application prevents the light from rising or falling sharply, which can effectively ensure the relative illumination of the external field of view, reasonably limit the range of incident light, eliminate light with poor edge quality, and improve the imaging quality of the lens. Attached Figure Description

[0023] 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:

[0024] Figure 1 A structural layout diagram and schematic diagram of some parameters of an optical imaging system according to this application are shown;

[0025] Figures 2A to 2C A schematic diagram of the structure of an optical imaging system according to Embodiment 1 of this application is shown;

[0026] 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.

[0027] Figures 4A to 4C A schematic diagram of the structure of an optical imaging system according to Embodiment 2 of this application is shown;

[0028] 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.

[0029] Figures 6A to 6C A schematic diagram of the structure of an optical imaging system according to Embodiment 3 of this application is shown; and

[0030] 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

[0031] 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.

[0032] 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.

[0033] 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 strictly to scale.

[0034] 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.

[0035] 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.

[0036] 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.

[0037] It should be noted that, unless otherwise specified, the embodiments and features described in the embodiments of this application can be combined with each other. The following embodiments only illustrate several implementation methods of this application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the patent application. 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 this application, and these all fall within the protection scope of this application. For example, the lens groups (i.e., the first lens to the fourth lens), lens barrel, and spacer elements in the various embodiments of this application can be arbitrarily combined, and it is not limited to the lens group in one embodiment being combined only with the lens barrel, spacer elements, etc. of that embodiment.

[0038] The present application will now be described in detail with reference to the accompanying drawings and embodiments. Figure 1 This diagram illustrates the structural layout and schematic diagrams of some parameters of an optical imaging system according to this application. Those skilled in the art will understand that some lens parameters frequently used in the art, such as the center thickness CT2 of the second lens on the optical axis, are not shown. Figure 1 As shown in the figure, Figure 1 The present application only exemplarily illustrates some parameters of the lens barrel and spacer element of an optical imaging system to facilitate a better understanding of the invention. Figure 1 As shown:

[0039] EP12 represents the distance between the first spacer element and the second spacer element along the optical axis;

[0040] CP1 represents the maximum thickness of the first spacer element along the optical axis.

[0041] CP6 represents the maximum thickness of the sixth spacer element along the optical axis.

[0042] L represents the maximum height of the lens barrel along the optical axis (i.e., the distance along the optical axis from the object-side end of the lens barrel near the object side to the image-side end of the lens barrel near the image side).

[0043] D0s represents the outer diameter of the object-side end of the microscope tube closest to the object side;

[0044] d0s represents the inner diameter of the object-side end of the microscope tube closest to the object side;

[0045] D1s represents the outer diameter of the object side of the first spacer element;

[0046] d1s represents the inner diameter of the object side of the first spacer element;

[0047] d1m represents the inner diameter of the image-side surface of the first spacer element;

[0048] D1m represents the outer diameter of the image side of the first spacer element;

[0049] D0m represents the outer diameter of the end of the lens barrel closest to the image side;

[0050] d0m represents the inner diameter of the end of the lens barrel closest to the image side;

[0051] D6s represents the outer diameter of the object side of the sixth spacer element;

[0052] d6s represents the inner diameter of the object side of the sixth spacer element;

[0053] D6m represents the outer diameter of the image-side surface of the sixth spacer element; and

[0054] d6m represents the inner diameter of the image side of the sixth spacer element.

[0055] The features, principles and other aspects of this application are described in detail below.

[0056] In an exemplary embodiment, the optical imaging system according to an exemplary embodiment of this application includes a lens barrel and a lens group and a plurality of spacer elements disposed within the lens barrel. The lens group includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens arranged sequentially along the optical axis from the object side to the image side.

[0057] In an exemplary embodiment, the first lens has positive optical power, the second lens has negative optical power, the third lens has negative optical power, the fourth lens has either positive or negative optical power, the fifth lens has positive optical power, the sixth lens has positive optical power, and the seventh lens has negative optical power. The second lens is a meniscus lens. By controlling the optical power of each lens and the surface shape of the second lens, the optical imaging system achieves good optical performance with a large image plane and a long back focal length.

[0058] In an exemplary embodiment, the plurality of spacer elements includes at least four spacer elements. The spacer elements help to ensure the stability of the lens assembly, effectively ensure the thickness of the air gap in the lens, make the lens optical parameters meet the design requirements, prevent interference between the lens and the effective diameter surface of the lens in the optical axis direction after assembly, and effectively block stray light, avoid lens appearance problems and performance abnormalities, and improve appearance and performance yield.

[0059] In an exemplary embodiment, the plurality of spacer elements may include: a first spacer element, a second spacer element, a third spacer element, a fourth spacer element, a fifth spacer element, and a sixth spacer element. Among them, the first spacer element is disposed on the image side of the first lens and at least partially contacts the image side of the first lens; the second spacer element is disposed on the image side of the second lens and at least partially contacts the image side of the second lens; the third spacer element is disposed on the image side of the third lens and at least partially contacts the image side of the third lens; the fourth spacer element is disposed on the image side of the fourth lens and at least partially contacts the image side of the fourth lens; the fifth spacer element is disposed on the image side of the fifth lens and at least partially contacts the image side of the fifth lens; the sixth spacer element is disposed on the image side of the sixth lens and at least partially contacts the image side of the sixth lens. By blocking part of the optical path with the second spacer element, it not only reduces aberrations such as coma within a certain range, but also ensures that the relative illumination is in an acceptable state. The third spacer element can limit the light path emitted from the part of the third lens mechanism, block the stray light path generated by the lens mechanism part, and then improve the incident guarantee of the effective light path and the relative illumination of the outer field of view.

[0060] In an exemplary embodiment, the inner diameter and the outer diameter of the object side and the image side of at least one spacer element among the plurality of spacer elements are equal. Since the inner diameter and the outer diameter of the object side and the image side of the spacer element are equal, there is no need to distinguish between the front and the back during the assembly process, which greatly reduces the difficulty of the lens assembly process. Exemplarily, the spacer element with equal inner diameter and outer diameter on the object side and the image side can be a relatively thin spacer element (usually with a thickness of less than 0.05 mm).

[0061] In an exemplary embodiment, the optical imaging system according to the present application can satisfy: 2.5 < f × tan(Semi-FOV) / (d6m - d5m) < 11.5, where f is the effective focal length of the optical imaging system, Semi-FOV is the maximum semi-field angle of the optical imaging system, d6m is the inner diameter of the image side of the sixth spacer element, and d5m is the inner diameter of the image side of the fifth spacer element. More specifically, f, Semi-FOV, d6m, and d5m can further satisfy: 4.2 < f × tan(Semi-FOV) / (d6m - d5m) < 10.0. Satisfying 2.5 < f × tan(Semi-FOV) / (d6m - d5m) < 11.5, reasonably setting spacer elements between the lenses is beneficial to enhancing the stability of the lens, facilitating the后期调整镜头MTF性能且同时有效的吸收通过透镜折射后的多余光线,减少杂光,本申请的光学成像系统通过约束第五间隔元件、第六间隔元件的口径差,防止光线陡升或者陡降,可有效的保证外视场的相对照度,能够合理限制入射光线的范围,剔除边缘质量较差的光线,提高镜头的成像质量。

[0062] It should be noted that there seems to be an unclear expression "后期调整镜头MTF性能" in the original text. You may need to check and clarify this part for a more accurate translation.In an exemplary embodiment, the optical imaging system according to the present application may satisfy: -7.5 < R10 / R11 < -1.5, where R10 is the radius of curvature of the image side of the fifth lens, and R11 is the radius of curvature of the object side of the sixth lens. More specifically, R10 and R11 may further satisfy: -6.6 < R10 / R11 < -2.3. The fifth lens and the sixth lens mainly play a role in the transition of the light propagation angle from small to large. Satisfying -7.5 < R10 / R11 < -1.5 helps to meet the designed aperture size and ensures the relative illuminance of the edge field of view.

[0063] In an exemplary embodiment, the optical imaging system according to the present application may satisfy: 32.0 < d3m / T34 + D2s / T23 < 125.5, where d3m is the inner diameter of the image side of the third spacer element, T34 is the air gap on the optical axis between the third lens and the fourth lens, D2s is the outer diameter of the object side of the second spacer element, and T23 is the air gap on the optical axis between the second lens and the third lens. More specifically, d3m, T34, D2s, and T23 may further satisfy: 36.0 < d3m / T34 + D2s / T23 < 125.0. Satisfying 32.0 < d3m / T34 + D2s / T23 < 125.5 limits the air gaps on the optical axis between the second lens and the third lens and between the third lens and the fourth lens in the optical imaging system, which can reduce the deflection of light rays on the surfaces of some lenses, thereby reducing the tolerance sensitivity.

[0064] In an exemplary embodiment, the optical imaging system according to the present application may satisfy: 1.0 < (D1s - d1m) / (CP1 - T12 + CT2) < 6.5, where D1s is the outer diameter of the object side of the first spacer element, d1m is the inner diameter of the image side of the first spacer element, CP1 is the maximum thickness of the first spacer element along the optical axis direction, T12 is the air gap on the optical axis between the first lens and the second lens, and CT2 is the central thickness of the second lens on the optical axis. More specifically, D1s, d1m, CP1, T12, and CT2 may further satisfy: 2.0 < (D1s - d1m) / (CP1 - T12 + CT2) < 6.1. Satisfying 1.0 < (D1s - d1m) / (CP1 - T12 + CT2) < 6.5 can adjust the air intervals between the lenses, reduce the sensitivity of field curvature, and at the same time improve the control of the lens thickness, which is beneficial to improving the formability of the lens. In addition, controlling the central thickness of each lens and restricting the intervals between the lenses can ensure the stability of the lens optical system to obtain good imaging effects.

[0065] In an exemplary embodiment, the optical imaging system according to this application satisfies: 7.5 < (D2s + D1m) / (R1 - R3) < 16.0, where D2s is the outer diameter of the object-side surface of the second spacer element, D1m is the outer diameter of the image-side surface of the first spacer element, R1 is the radius of curvature of the object-side surface of the first lens, and R3 is the radius of curvature of the object-side surface of the second lens. More specifically, D2s, D1m, R1, and R3 can further satisfy: 8.0 < (D2s + D1m) / (R1 - R3) < 15.0. Satisfying 7.5 < (D2s + D1m) / (R1 - R3) < 16.0 can reasonably limit the range of light path emitted from the first lens and incident on the second lens, eliminate light rays with poor edge quality, and effectively improve the stability of the first and second lens assembly, reduce the sensitivity of the lens assembly structure, and improve the imaging quality of the lens.

[0066] In an exemplary embodiment, the optical imaging system according to this application satisfies: 1.0 < (CT4 + CT5) / (CP4 + CP5) < 55.5, where CT4 is the center thickness of the fourth lens on the optical axis, CT5 is the center thickness of the fifth lens on the optical axis, CP4 is the maximum thickness of the fourth spacer element along the optical axis, and CP5 is the maximum thickness of the fifth spacer element along the optical axis. More specifically, CT4, CT5, CP4, and CP5 further satisfy: 1.6 < (CT4 + CT5) / (CP4 + CP5) < 54.4. Satisfying 1.0 < (CT4 + CT5) / (CP4 + CP5) < 55.5 constrains the center thicknesses of the fourth and fifth lenses, as well as the thicknesses of the fourth and fifth spacers, within a reasonable range, which is beneficial for reducing meridional astigmatism in the off-axis field of view during the balance optimization.

[0067] In an exemplary embodiment, the optical imaging system according to this application satisfies: 4.5 < (D6s + d1s) / (R1 + R11) < 9.5, where D6s is the outer diameter of the object-side surface of the sixth spacer element, d1s is the inner 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, and R11 is the radius of curvature of the object-side surface of the sixth lens. More specifically, D6s, d1s, R1, and R11 further satisfy: 5.1 < (D6s + d1s) / (R1 + R11) < 8.7. Satisfying 4.5 < (D6s + d1s) / (R1 + R11) < 9.5 is beneficial for limiting the range of incident and outgoing light rays, thereby controlling the relative illumination of the external field of view within a reasonable range, and also helps to reduce assembly bearing gaps and improve assembly stability.

[0068] In an exemplary embodiment, the optical imaging system according to the present application may satisfy: 3.5 < (f + f56) / (EP36 - ∑CP) < 15.5, where f is the effective focal length of the optical imaging system, f56 is the combined focal length of the fifth lens and the sixth lens, EP36 is the distance between the third spacer element and the sixth spacer element along the optical axis direction, and ∑CP is the sum of the maximum thicknesses of the first spacer element to the sixth spacer element along the optical axis direction. More specifically, f, f56, EP36, and ∑CP may further satisfy: 4.4 < (f + f56) / (EP36 - ∑CP) < 14.8. Satisfying 3.5 < (f + f56) / (EP36 - ∑CP) < 15.5 is beneficial for making the BFL long enough to meet the spatial size of other components in the module under the condition of TTL locking, while ensuring that the light transmission aperture of the system is within the required range.

[0069] In an exemplary embodiment, the optical imaging system according to the present application may satisfy: 0 < D4m / R9 + d4s / R8 < 6.0, where D4m is the outer diameter of the image side of the fourth spacer element, d4s is the inner diameter of the object side of the fourth spacer element, R9 is the curvature radius of the object side of the fifth lens, and R8 is the curvature radius of the image side of the fourth lens. More specifically, D4m, R9, d4s, and R8 may further satisfy: 0.6 < D4m / R9 + d4s / R8 < 5.0. Satisfying 0 < D4m / R9 + d4s / R8 < 6.0 and controlling the outer diameter of the image side of the fourth spacer element and the inner diameter of the object side of the fourth spacer element is beneficial for restricting the intensity of the light emitted by the fourth lens, improving the internal stray light of the fourth lens, and at the same time, combining the ratio of the outer diameter of the image side of the fourth spacer element to the curvature radius of the object side of the fifth lens to further restrict the length of the fifth lens mechanism, which is more beneficial for lens forming and improving the problem of yield fluctuation during the assembly process.

[0070] In an exemplary embodiment, the optical imaging system according to this application satisfies: -41.5 < (d4s - d5m) / (R9 + R11) < 12.5, where d4s is the inner diameter of the object-side surface of the fourth spacer element, d5m is the inner diameter of the image-side surface of the fifth spacer element, R9 is the radius of curvature of the object-side surface of the fifth lens, and R11 is the radius of curvature of the object-side surface of the sixth spacer element. More specifically, d4s, d5m, R9, and R11 further satisfy: -41.0 < (d4s - d5m) / (R9 + R11) < 11.6. The condition -41.5 < (d4s - d5m) / (R9 + R11) < 12.5 is satisfied. By controlling the ratio of the inner diameter difference between the fourth and fifth spacer elements to the curvature radius of the fifth and sixth lenses, the optical power of the lens is limited, preventing stray light problems caused by excessive lens curvature. At the same time, controlling the inner diameter of the object side of the fourth spacer element and the inner diameter of the image side of the fifth spacer element helps to control the light drop on both sides of the fifth lens, intercepting excess light in the outer field of view and improving image quality.

[0071] In an exemplary embodiment, the optical imaging system according to this application satisfies: 4.0 < (f5-f7) / (EP45+EP56) < 12.5, where f5 is the effective focal length of the fifth lens, f7 is the effective focal length of the seventh lens, EP45 is the distance between the fourth and fifth spacer elements on the optical axis, and EP56 is the distance between the fifth and sixth spacer elements on the optical axis. More specifically, f5, f7, EP45, and EP56 further satisfy: 4.8 < (f5-f7) / (EP45+EP56) < 11.4. Satisfying 4.0 < (f5-f7) / (EP45+EP56) < 12.5 is beneficial for reasonably limiting the optical path range exiting from the fifth lens and entering the seventh lens, eliminating light rays with poor edge quality, and effectively improving the stability of the assembly of the fifth, sixth, and seventh lenses, reducing the sensitivity of the inter-lens assembly structure, and improving the imaging quality of the lens.

[0072] In an exemplary embodiment, the optical imaging system according to this application satisfies: 4.5 < (L + TD) / (∑AT - ∑CP) < 14.5, where L is the maximum height of the lens barrel along the optical axis, TD is the distance on the optical axis from the object side of the first lens to the image side of the seventh lens, ∑AT is the sum of the air gaps between any two adjacent lenses from the first to the seventh lens on the optical axis, and ∑CP is the sum of the maximum thicknesses along the optical axis from the first to the sixth spacer element. More specifically, L, TD, ∑AT, and ∑CP can further satisfy: 5.7 < (L + TD) / (∑AT - ∑CP) < 12.2. Satisfying 4.5 < (L + TD) / (∑AT - ∑CP) < 14.5, by limiting the length of the lens body to achieve a thinner lens, a longer back focal length can be achieved to reserve more travel space for the motor, resulting in a clear focusing effect. At the same time, the positional relationship between the lens and the spacer element is reasonably allocated, reducing the sensitivity of the lens field area, which is beneficial to improving the mass production yield.

[0073] In an exemplary embodiment, the optical imaging system according to this application satisfies: 5.5 < (d5m + d6m) / (CT5 + CT6) < 11.5, where d5m is the inner diameter of the image-side surface of the fifth spacer element, d6m is the inner diameter of the image-side surface of the sixth spacer element, CT5 is the center thickness of the fifth lens on the optical axis, and CT6 is the center thickness of the sixth lens on the optical axis. More specifically, d5m, d6m, CT5, and CT6 can further satisfy: 6.2 < (d5m + d6m) / (CT5 + CT6) < 10.2. Satisfying 5.5 < (d5m + d6m) / (CT5 + CT6) < 11.5 limits the ratio of the inner diameter of the image-side surface of the fifth and sixth spacer elements to the center thickness of the adjacent lenses, effectively restricting the outgoing light rays from the lenses. This improves the effect of stray light within the lenses while eliminating the influence of external field-of-view rays on off-axis aberrations, thus improving image quality. This also constrains the center thickness of the fifth and sixth lenses, making the lenses more uniform within a reasonable processing range.

[0074] In an exemplary embodiment, the optical imaging system according to the present application may satisfy: 0.5 < (D4m - d4s) / (CT4 - T45) < 6.0, where D4m is the outer diameter of the image side of the fourth spacer element, d4s is the inner diameter of the object side of the fourth spacer element, CT4 is the central thickness of the fourth lens on the optical axis, and T45 is the air gap between the fourth lens and the fifth lens on the optical axis. More specifically, D4m, d4s, CT4, and T45 may further satisfy: 1.2 < (D4m - d4s) / (CT4 - T45) < 5.0. Satisfying 0.5 < (D4m - d4s) / (CT4 - T45) < 6.0 is beneficial to enhancing the structural stability of the fourth lens, while the force conduction is uniform during the assembly process, reducing the change in the central force of the third lens and the fifth lens, and is also beneficial to reasonably distributing the positions of the third lens and the fifth lens in the optical imaging system, reducing the sensitivity of the gap field curvature between the fourth lens and the third lens and the fifth lens respectively, so that the optical system obtains a good imaging effect.

[0075] In an exemplary embodiment, the optical imaging system according to the present application may satisfy: 10.5 < f × Fno / (D0m - d0m) < 44.5, where f is the effective focal length of the optical imaging system, FNO is the f-number of the optical imaging system, D0m is the outer diameter of the image-side end of the lens barrel close to the image side, and d0m is the inner diameter of the image-side end of the lens barrel close to the image side. More specifically, f, Fno, D0m, and d0m may further satisfy: 11.3 < f × Fno / (D0m - d0m) < 43.1. Satisfying 10.5 < f × Fno / (D0m - d0m) < 44.5 restricts the size of the aperture and the effective focal length of the lens while fixing the image-side wall thickness of the lens barrel, which is beneficial to ensuring that the light transmission of the system is within the required range and the size of the magnification.

[0076] In an exemplary embodiment, the optical imaging system according to the present application may satisfy: 5.0 < (L - D0m) / (BFL - ∑CT) < 19.5, where L is the maximum height of the lens barrel along the optical axis, TD is the distance on the optical axis from the object side of the first lens to the image side of the seventh lens, D0m is the outer diameter of the image-side end of the lens barrel close to the image side, TTL is the distance on the optical axis from the object side of the first lens to the imaging surface of the optical imaging system, and ∑CT is the sum of the central thicknesses of the first lens to the seventh lens on the optical axis. More specifically, f, Fno, D0m, and d0m may further satisfy: 6.2 < (L - D0m) / (BFL - ∑CT) < 18.8. Satisfying 5.0 < (L - D0m) / (BFL - ∑CT) < 19.5 meets the requirements of lens processing by restricting the length of the optical body, while axially reducing the length of the lens body, and reasonably distributing the lens air gap without affecting the light input to improve the process yield.

[0077] In an exemplary embodiment, the effective focal length f of the optical imaging system can be, for example, in the range of 9.8 mm to 12.6 mm, the effective focal length f1 of the first lens can be, for example, in the range of 9.8 mm to 10.7 mm, the effective focal length f2 of the second lens can be, for example, in the range of -18.4 mm to -13.2 mm, the effective focal length f3 of the third lens can be, for example, in the range of -78.9 mm to -28.0 mm, the effective focal length f4 of the fourth lens can be, for example, in the range of -37.7 mm to 32.5 mm, the effective focal length f5 of the fifth lens can be, for example, in the range of 5.4 mm to 14.5 mm, the effective focal length f6 of the sixth lens can be, for example, in the range of 7.2 mm to 15.9 mm, and the effective focal length f7 of the seventh lens can be, for example, in the range of -8.2 mm to -5.8 mm. The f-number Fno of the optical imaging system can satisfy 1.8 < Fno < 2.1; the maximum semi-field angle Semi-FOV of the optical imaging system can satisfy 29.7° < Semi-FOV < 33.0°; the total optical length TTL of the optical imaging system can satisfy 11.7 mm < TTL < 14.8 mm.

[0078] In an exemplary embodiment, the maximum height L of the lens barrel along the optical axis direction and the effective focal length f of the optical imaging system satisfy: 0.7 < L / f < 0.9. Reasonably controlling the ratio of L and f of the optical imaging system is beneficial to maintaining the miniaturization characteristics of the optical imaging system and obtaining a reasonable optical effective focal length.

[0079] In an embodiment of the present application, at least one of the lens surfaces of each lens is an aspherical lens surface, that is, at least one of the object side surfaces of the first lens to the image side surfaces of the seventh 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 astigmatism aberration. After using an aspherical lens, it is possible to eliminate the aberration that appears during imaging as much as possible, thereby improving the imaging quality. Optionally, the object side surfaces and image side surfaces of all the lenses from the first lens to the seventh lens are aspherical lens surfaces.

[0080] In an exemplary embodiment, the above optical imaging system may further include a filter for correcting color deviation and / or a protective glass for protecting the photosensitive element located on the imaging surface.

[0081] The optical imaging system according to the above embodiments of this application can employ multiple lenses, such as the seven lenses mentioned above. By rationally allocating the optical power, surface shape, and arrangement of the spacers of each lens, the range of each lens-tube engagement is made more uniform, enhancing the light-gathering ability and ensuring good imaging quality with a long back focal length and a large image plane. However, those skilled in the art should understand that the number of lenses constituting the optical imaging system can be changed without departing from the technical solutions claimed in this application to obtain the various results and advantages described in this specification. For example, although seven lenses are described as an example in the embodiments, the optical imaging system is not limited to including seven lenses. If necessary, the optical imaging system may also include other numbers of lenses.

[0082] Specific embodiments of the optical imaging system applicable to the above-described embodiments are further described below with reference to the accompanying drawings.

[0083] Example 1

[0084] The following is for reference Figures 2A to 3D The optical imaging system 1001, optical imaging system 1002 and optical imaging system 1003 according to Embodiment 1 of this application are described. Figures 2A to 2C Schematic diagrams of optical imaging systems 1001, 1002 and 1003 according to Embodiment 1 of this application are shown respectively.

[0085] like Figures 2A to 2C As shown, optical imaging systems 1001, 1002 and 1003 each include a lens barrel P0, lens groups E1 to E7 and multiple spacer elements P1 to P6.

[0086] like Figures 2A to 2CAs shown, optical imaging systems 1001, 1002, and 1003 employ the same lens group, which, from the object side to the image side, sequentially 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, and a seventh lens E7. 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 negative optical power, with its object-side surface S5 being convex and its image-side surface S6 being concave. The fourth lens E4 has positive 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 concave and its image-side surface S14 being concave. The filter E8 has an object-side surface S15 and an image-side surface S16. Light from the object passes sequentially through each surface S1 to S16 and is finally imaged on the imaging surface S17.

[0087] Table 1 shows the basic parameters of the lens groups of optical imaging systems 1001, 1002 and 1003 of Embodiment 1, wherein the units of radius of curvature, thickness and effective focal length are all millimeters (mm).

[0088]

[0089]

[0090] Table 1

[0091] In this example, the effective focal length f of optical imaging systems 1001, 1002, and 1003 is 12.50 mm, the total optical length TTL of optical imaging systems 1001, 1002, and 1003 is 14.70 mm, the maximum semi-field of view (Semi-FOV) of optical imaging systems 1001, 1002, and 1003 is 32.93°, and the aperture number Fno of optical imaging systems 1001, 1002, and 1003 is 2.09.

[0092] In Embodiment 1, the object-side surface and image-side surface of any one of the first lens E1 to the seventh lens E7 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:

[0093]

[0094] 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, A14 that can be used for each aspherical mirror S1-S14 in Example 1. 10 A 12 A 14 A 16 A 18 A 20 A 22 A 24 A 26 A 28 and A 30 .

[0095] Face number A4 A6 A8 A10 A12 A14 A16 S1 1.32E-01 3.53E-02 1.19E-02 3.24E-03 8.74E-04 -2.16E-04 -4.46E-04 S2 3.48E-01 -1.48E-02 2.01E-02 -6.87E-03 -8.19E-04 -1.88E-03 1.30E-03 S3 -1.03E+00 -5.32E-02 -1.73E-02 -1.36E-02 -3.83E-03 1.02E-03 1.12E-03 S4 -1.96E-01 8.84E-02 -3.82E-03 -5.96E-03 -2.27E-03 3.07E-03 8.79E-04 S5 -9.44E-01 2.72E-02 -1.24E-02 1.17E-04 -3.39E-04 -2.00E-04 -3.35E-04 S6 -1.07E+00 1.20E-01 -7.90E-03 4.13E-03 -2.17E-03 -1.67E-03 -1.22E-03 S7 3.93E-01 -6.69E-02 2.83E-02 1.58E-03 -1.41E-04 -7.97E-04 -8.39E-04 S8 -4.80E-01 3.39E-02 2.85E-02 1.60E-02 5.38E-03 3.72E-03 5.45E-05 S9 -2.24E+00 3.66E-01 5.72E-03 -2.19E-02 4.51E-03 5.41E-03 -3.48E-03 S10 -2.27E+00 1.55E-01 4.09E-02 9.19E-03 2.18E-02 -1.94E-03 -6.35E-03 S11 5.52E-02 -1.17E-01 -1.39E-01 2.63E-02 4.67E-02 4.83E-03 -1.44E-03 S12 3.11E+00 -1.41E-01 3.35E-03 -6.93E-02 3.32E-02 -5.83E-03 5.14E-03 S13 -1.78E+00 4.97E-01 6.06E-02 -1.03E-01 -1.66E-02 4.03E-03 1.74E-02 S14 -7.75E+00 1.70E+00 -3.33E-01 1.30E-01 -7.75E-02 2.28E-02 -1.50E-02

[0096] Table 2-1

[0097]

[0098]

[0099] Table 2-2

[0100] like Figures 2A to 2C As shown, optical imaging systems 1001, 1002, and 1003 each include a first spacer element P1, a second spacer element P2, a third spacer element P3, a fourth spacer element P4, a fifth spacer element P5, and a sixth spacer element P6. The first spacer element P1 is positioned on the image-side surface of the first lens E1 and is at least partially in contact with it; the second spacer element P2 is positioned on the image-side surface of the second lens E2 and is at least partially in contact with it; the third spacer element P3 is positioned on the image-side surface of the third lens E3 and is at least partially in contact with it; the fourth spacer element P4 is positioned on the image-side surface of the fourth lens E4 and is at least partially in contact with it; the fifth spacer element P5 is positioned on the image-side surface of the fifth lens E5 and is at least partially in contact with it; and the sixth spacer element P6 is positioned on the image-side surface of the sixth lens E6 and is at least partially in contact with it.

[0101] like Figure 2AAs shown, the optical imaging system 1001 further includes a first auxiliary spacer P1b disposed on the image-side surface of the first spacer P1 and at least partially in contact with the image-side surface of the first spacer P1, and a fourth auxiliary spacer P4b disposed on the image-side surface of the fourth spacer P4 and at least partially in contact with the image-side surface of the fourth spacer P4; as shown Figure 2B As shown, the optical imaging system 1002 further includes a first auxiliary spacer element P1b disposed on the image-side surface of the first spacer element P1 and in at least partial contact with the image-side surface of the first spacer element P1; as shown Figure 2C As shown, the optical imaging system 1003 further includes a fourth auxiliary spacer element P4b, which is disposed on the image side of the fourth spacer element P4 and is at least partially in contact with the image side of the fourth spacer element P4.

[0102] The aforementioned spacer elements can block excess external light from entering, allowing the lens to better support the lens barrel and enhancing the structural stability of optical imaging systems 1001, 1002, and 1003.

[0103] Table 3 shows the basic parameters of the spacer elements and lens barrels of the optical imaging systems 1001, 1002 and 1003 of Embodiment 1.

[0104]

[0105]

[0106] Table 3

[0107] Figure 3A The on-axis chromatic aberration curves of optical imaging systems 1001, 1002 and 1003 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, 1002 and 1003 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, 1002 and 1003 of Embodiment 1 are shown, which represent the distortion magnitude values ​​corresponding to different image heights. Figure 3D The magnification chromatic aberration curves of optical imaging systems 1001, 1002, and 1003 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, optical imaging system 1002 and optical imaging system 1003 given in Example 1 can achieve good imaging quality.

[0108] Example 2

[0109] The following is for reference Figures 4A to 5D The optical imaging system 2001, optical imaging system 2002, and optical imaging system 2003 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 4C Schematic diagrams of optical imaging systems 2001, 2002 and 2003 according to Embodiment 2 of this application are shown respectively.

[0110] like Figures 4A to 4C As shown, optical imaging systems 2001, 2002 and 2003 each include a lens barrel P0, lens groups E1 to E7 and multiple spacer elements P1 to P6.

[0111] like Figures 4A to 4C As shown, optical imaging systems 2001, 2002, and 2003 employ the same lens group, which, from the object side to the image side, sequentially 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, and a seventh lens E7. 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 negative 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 convex and its image-side surface S8 being concave. 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 filter E8 has an object-side surface S15 and an image-side surface S16. Light from the object passes sequentially through each surface S1 to S16 and is finally imaged on the imaging surface S17.

[0112] In this example, the effective focal length f of optical imaging systems 2001, 2002, and 2003 is 10.19 mm, the total optical length TTL of optical imaging systems 2001, 2002, and 2003 is 12.04 mm, the maximum semi-field-of-view (Semi-FOV) of optical imaging systems 2001, 2002, and 2003 is 29.75°, and the aperture number Fno of optical imaging systems 2001, 2002, and 2003 is 1.85.

[0113] Table 4 shows the basic parameters of the lens groups of optical imaging systems 2001, 2002 and 2003 of Embodiment 2, wherein the units of radius of curvature, thickness and effective 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.

[0114]

[0115] Table 4

[0116]

[0117]

[0118] Table 5-1

[0119] Face number A18 A20 A22 A24 A26 A28 A30 S1 -1.24E-05 8.54E-06 3.34E-06 -1.15E-06 -5.97E-06 0.00E+00 0.00E+00 S2 1.26E-04 -7.31E-05 2.42E-05 -2.57E-05 1.54E-05 0.00E+00 0.00E+00 S3 1.22E-04 -4.86E-05 1.67E-05 -2.17E-05 6.37E-06 -6.28E-07 1.48E-06 S4 -6.67E-05 -7.23E-05 -5.13E-05 -2.83E-05 -9.94E-06 0.00E+00 0.00E+00 S5 -1.09E-04 -1.16E-04 -6.84E-05 -4.87E-05 -2.52E-05 -1.20E-05 0.00E+00 S6 5.83E-06 -8.77E-05 -1.75E-06 -2.01E-05 -2.96E-06 0.00E+00 0.00E+00 S7 1.36E-04 -7.04E-05 3.48E-05 -1.39E-05 1.75E-06 0.00E+00 0.00E+00 S8 6.50E-04 -2.76E-04 1.18E-04 -5.27E-05 2.11E-05 -4.07E-06 0.00E+00 S9 5.13E-04 -3.84E-04 1.22E-04 -5.06E-05 2.69E-05 0.00E+00 0.00E+00 S10 1.28E-04 5.60E-05 -1.00E-04 -1.67E-05 2.40E-07 2.25E-05 0.00E+00 S11 -1.14E-05 1.52E-04 -3.19E-05 3.83E-05 -9.84E-06 1.63E-05 -3.89E-06 S12 -7.20E-04 5.66E-04 2.03E-04 2.17E-05 -1.15E-04 -6.72E-06 0.00E+00 S13 1.12E-03 3.43E-04 -1.62E-05 -5.57E-05 -6.50E-05 1.27E-05 0.00E+00 S14 2.56E-03 -1.16E-03 5.65E-04 -2.42E-04 1.23E-04 -4.27E-05 2.34E-05

[0120] Table 5-2

[0121] like Figures 4A to 4C As shown, optical imaging systems 2001, 2002, and 2003 each include a first spacer element P1, a second spacer element P2, a third spacer element P3, a fourth spacer element P4, a fifth spacer element P5, and a sixth spacer element P6. The first spacer element P1 is positioned on the image-side surface of the first lens E1 and is at least partially in contact with it; the second spacer element P2 is positioned on the image-side surface of the second lens E2 and is at least partially in contact with it; the third spacer element P3 is positioned on the image-side surface of the third lens E3 and is at least partially in contact with it; the fourth spacer element P4 is positioned on the image-side surface of the fourth lens E4 and is at least partially in contact with it; the fifth spacer element P5 is positioned on the image-side surface of the fifth lens E5 and is at least partially in contact with it; and the sixth spacer element P6 is positioned on the image-side surface of the sixth lens E6 and is at least partially in contact with it.

[0122] like Figure 4A As shown, the optical imaging system 2001 further includes a third auxiliary spacer element P3b, which is disposed on the image side of the third spacer element P3 and is at least partially in contact with the image side of the third spacer element P3.

[0123] The aforementioned spacer elements can block excess external light from entering, allowing the lens to better support the lens barrel and enhancing the structural stability of optical imaging systems 2001, 2002, and 2003.

[0124] Table 6 shows the basic parameters of the spacer elements and lens barrels of optical imaging systems 2001, 2002 and 2003 of Embodiment 2.

[0125]

[0126]

[0127] Table 6

[0128] Figure 5A The on-axis chromatic aberration curves of optical imaging systems 2001, 2002 and 2003 of Embodiment 2 are shown, which indicate 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, 2002 and 2003 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, 2002 and 2003 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, 2002, and 2003 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, optical imaging system 2002 and optical imaging system 2003 given in Example 2 can achieve good imaging quality.

[0129] Example 3

[0130] The following is for reference Figures 6A to 7D The optical imaging system 3001, optical imaging system 3002 and optical imaging system 3003 according to Embodiment 3 of this application are described. Figures 6A to 6C Schematic diagrams of optical imaging systems 3001, 3002 and 3003 according to Embodiment 3 of this application are shown respectively.

[0131] like Figures 6A to 6C As shown, optical imaging systems 3001, 3002 and 3003 each include a lens barrel P0, lens groups E1 to E7 and multiple spacer elements P1 to P6.

[0132] like Figures 6A to 6CAs shown, optical imaging systems 3001, 3002, and 3003 employ the same lens group, which, from the object side to the image side, sequentially 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, and a seventh lens E7. 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 negative 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 convex and its image-side surface S8 being concave. 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 filter E8 has an object-side surface S15 and an image-side surface S16. Light from the object passes sequentially through each surface S1 to S16 and is finally imaged on the imaging surface S17.

[0133] In this example, the effective focal length f of optical imaging systems 3001, 3002, and 3003 is 9.81 mm, the total optical length TTL of optical imaging systems 3001, 3002, and 3003 is 11.80 mm, the maximum semi-field-of-view (Semi-FOV) of optical imaging systems 3001, 3002, and 3003 is 32.46°, and the aperture number Fno of optical imaging systems 3001, 3002, and 3003 is 1.85.

[0134] Table 7 shows the basic parameters of the lens groups of optical imaging systems 3001, 3002 and 3003 of Embodiment 3, wherein the units of radius of curvature, thickness and effective 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.

[0135]

[0136] Table 7

[0137]

[0138]

[0139] Table 8-1

[0140] Face number A18 A20 A22 A24 A26 A28 A30 S1 -1.97E-05 -5.09E-06 1.68E-06 6.25E-06 4.31E-06 0.00E+00 0.00E+00 S2 4.01E-05 -1.36E-05 1.33E-05 -2.12E-06 5.44E-06 0.00E+00 0.00E+00 S3 6.24E-05 2.72E-06 2.56E-05 6.70E-06 1.38E-05 2.60E-06 4.40E-06 S4 -1.11E-04 -5.97E-05 -2.66E-05 -1.18E-05 0.00E+00 0.00E+00 0.00E+00 S5 -4.38E-05 -4.49E-05 -2.80E-05 -1.83E-05 -7.68E-06 -5.39E-06 0.00E+00 S6 4.47E-04 -2.05E-04 1.06E-04 2.70E-06 0.00E+00 0.00E+00 0.00E+00 S7 5.00E-04 -2.92E-04 1.56E-04 -6.81E-06 -1.03E-06 -4.00E-06 1.59E-06 S8 8.69E-04 -3.57E-04 1.89E-04 -8.28E-05 3.88E-05 -1.79E-05 4.69E-06 S9 6.79E-04 -4.42E-04 1.74E-04 -8.52E-05 4.90E-05 -1.34E-05 1.12E-05 S10 -2.43E-04 2.01E-05 7.89E-06 4.57E-05 2.56E-05 1.13E-05 0.00E+00 S11 -3.43E-04 -1.16E-04 -6.73E-05 -9.97E-06 -9.08E-06 -1.33E-05 -2.85E-06 S12 -9.45E-04 5.96E-04 2.76E-05 2.68E-05 -6.01E-05 1.99E-05 3.91E-06 S13 5.28E-04 4.74E-04 -9.47E-05 -2.54E-05 -1.32E-04 2.18E-05 -1.92E-05 S14 2.47E-03 -1.63E-03 5.83E-04 -3.93E-04 1.32E-04 -6.66E-05 4.36E-05

[0141] Table 8-2

[0142] like Figures 6A to 6C As shown, optical imaging systems 3001, 3002, and 3003 each include a first spacer element P1, a second spacer element P2, a third spacer element P3, a fourth spacer element P4, a fifth spacer element P5, and a sixth spacer element P6. The first spacer element P1 is positioned on the image-side surface of the first lens E1 and is at least partially in contact with it; the second spacer element P2 is positioned on the image-side surface of the second lens E2 and is at least partially in contact with it; the third spacer element P3 is positioned on the image-side surface of the third lens E3 and is at least partially in contact with it; the fourth spacer element P4 is positioned on the image-side surface of the fourth lens E4 and is at least partially in contact with it; the fifth spacer element P5 is positioned on the image-side surface of the fifth lens E5 and is at least partially in contact with it; and the sixth spacer element P6 is positioned on the image-side surface of the sixth lens E6 and is at least partially in contact with it.

[0143] like Figure 6A As shown, the optical imaging system 3001 further includes a first auxiliary spacer element P1b disposed on the image side of the first spacer element P1 and in at least partial contact with the image side of the first spacer element P1, and a fourth auxiliary spacer element P4b disposed on the image side of the fourth spacer element P4 and in at least partial contact with the image side of the fourth spacer element P4.

[0144] The aforementioned spacer elements can block excess external light from entering, allowing the lens to better support the lens barrel and enhancing the structural stability of optical imaging systems 3001, 3002, and 3003.

[0145] Table 9 shows the basic parameters of the spacer elements and lens barrels of optical imaging systems 3001, 3002 and 3003 of Embodiment 3.

[0146] Parameters / Optical Imaging System Optical Imaging System 3001 Optical Imaging System 3002 Optical Imaging System 3003 d1s 5.164 5.605 5.071 d1m 5.164 6.021 5.071 D1s 7.100 8.764 7.617 D1m 7.100 8.700 7.617 D2s 7.300 7.526 7.789 d3m 4.735 4.735 4.681 d4s 4.841 6.422 4.976 D4m 7.500 9.000 8.900 d5m 5.202 5.145 5.182 d6m 6.678 6.032 6.018 D6s 9.768 10.168 9.600 d0m 10.099 11.011 10.444 D0m 11.000 12.200 12.040 CP4 0.018 0.730 0.580 EP45 1.150 0.430 0.390 CP5 0.018 0.018 0.018 EP56 1.683 1.373 1.163 L 7.800 7.830 7.700 ∑CP 0.108 1.274 0.670 EP36 3.359 3.159 2.909 CP1 0.018 0.468 0.018

[0147] Table 9

[0148] Figure 7A The on-axis chromatic aberration curves of optical imaging systems 3001, 3002 and 3003 of Embodiment 3 are shown, which indicate the deviation of the focal point of light of different wavelengths after passing through the lens. Figure 7BAstigmatism curves of optical imaging systems 3001, 3002 and 3003 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, 3002 and 3003 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, 3002, and 3003 of Embodiment 3 are shown, representing the deviations in image height at different points 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, optical imaging system 3002 and optical imaging system 3003 given in Example 3 can achieve good imaging quality.

[0149] In summary, the optical imaging systems 1001, 1002, 1003, 2001, 2002, 2003, 3001, 3002 and 3003 of Examples 1 to 3 satisfy the relationships shown in Table 10.

[0150]

[0151]

[0152] Table 10

[0153] This application also provides an imaging device, whose electronic photosensitive element can be a photocoupled device (CCD) or a complementary metal oxide semiconductor device (CMOS). The imaging device can be a stand-alone imaging device such as a digital camera, or an imaging module integrated into a mobile electronic device such as a mobile phone. The imaging device is equipped with the optical imaging system described above.

[0154] 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: The lens group, along the optical axis from the object side to the image side, includes, in sequence: a first lens with positive optical power, a second lens with negative optical power, a third lens with negative optical power, a fourth lens with optical power, a fifth lens with positive optical power, a sixth lens with positive optical power, and a seventh lens with negative optical power, wherein the second lens is a meniscus lens. A plurality of spacer elements, including a fifth spacer element that at least partially contacts the image-side surface of the fifth lens and a sixth spacer element that at least partially contacts the image-side surface of the sixth lens; and A lens barrel for housing the lens group and the plurality of spacer elements; The optical imaging system has seven lenses with optical power. Wherein, the effective focal length f of the optical imaging system, the maximum semi-FOV of the optical imaging system, the inner diameter d6m of the image-side surface of the sixth spacer element, and the inner diameter d5m of the image-side surface of the fifth spacer element satisfy: 4.2 <f×tan(Semi-FOV) / (d6m-d5m)<10.0; The object-side surface of the first lens is convex, and the image-side surface is concave. The object-side surface of the fifth lens is convex, and the image-side surface is concave. The object-side surface of the sixth lens is concave, and the image-side surface is convex. The image-side surface of the seventh lens is concave.

2. The optical imaging system according to claim 1, characterized in that, The radius of curvature R10 of the image side of the fifth lens and the radius of curvature R11 of the object side of the sixth lens satisfy: -6.51≤R10 / R11≤-2.

40.

3. The optical imaging system according to claim 1, characterized in that, The plurality of spacers also includes a second spacer element that is at least partially in contact with the image side of the second lens and a third spacer element that is at least partially in contact with the image side of the third lens.

4. The optical imaging system according to claim 1, characterized in that, At least one of the plurality of spacer elements has an inner diameter equal to the object side and an outer diameter equal to the image side.

5. The optical imaging system according to claim 3, characterized in that, The inner diameter d3m of the image side of the third spacer element, the air gap T34 between the third lens and the fourth lens on the optical axis, the outer diameter D2s of the object side of the second spacer element, and the air gap T23 between the second lens and the third lens on the optical axis satisfy: 36.24≤d3m / T34+D2s / T23≤124.

91.

6. The optical imaging system according to claim 5, characterized in that, The plurality of spacer elements further includes a first spacer element that at least partially contacts the image-side surface of the first lens; wherein, The outer diameter D1s of the object side of the first spacer element, the inner diameter d1m of the image side of the first spacer element, the maximum thickness CP1 of the first spacer element along the optical axis, the air gap T12 between the first lens and the second lens on the optical axis, and the center thickness CT2 of the second lens on the optical axis satisfy: 2.09≤(D1s-d1m) / (CP1-T12+CT2)≤6.

02.

7. The optical imaging system according to claim 5, characterized in that, The plurality of spacer elements further includes a first spacer element that at least partially contacts the image-side surface of the first lens; wherein, The outer diameter D2s of the object side of the second spacer element, the outer diameter D1m of the image side of the first spacer element, the radius of curvature R1 of the object side of the first lens, and the radius of curvature R3 of the object side of the second lens satisfy: 8.11≤(D2s+D1m) / (R1-R3)≤14.

93.

8. The optical imaging system according to claim 5, characterized in that, The plurality of spacer elements further includes a fourth spacer element that is at least partially in contact with the image-side surface of the fourth lens, wherein, The center thickness CT4 of the fourth lens on the optical axis, the center thickness CT5 of the fifth lens on the optical axis, the maximum thickness CP4 of the fourth spacer element along the optical axis, and the maximum thickness CP5 of the fifth spacer element along the optical axis satisfy: 1.65≤(CT4+CT5) / (CP4+CP5)≤54.

33.

9. The optical imaging system according to any one of claims 1 to 8, characterized in that, The plurality of spacer elements further includes a first spacer element that at least partially contacts the image-side surface of the first lens; wherein, The outer diameter D6s of the object side of the sixth spacer element, the inner diameter d1s of the object side of the first spacer element, the radius of curvature R1 of the object side of the first lens, and the radius of curvature R11 of the object side of the sixth lens satisfy: 5.18≤(D6s+d1s) / (R1+R11)≤8.

60.

10. The optical imaging system according to any one of claims 1 to 8, characterized in that, The plurality of spacers further includes a first spacer element that at least partially contacts the image-side surface of the first lens, a second spacer element that at least partially contacts the image-side surface of the second lens, a third spacer element that at least partially contacts the image-side surface of the third lens, and a fourth spacer element that at least partially contacts the image-side surface of the fourth lens; wherein, The effective focal length f of the optical imaging system, the combined focal length f56 of the fifth lens and the sixth lens, the spacing EP36 between the third spacer and the sixth spacer along the optical axis, and the sum of the maximum thickness ∑CP from the first spacer to the sixth spacer along the optical axis satisfy: 4.49≤(f+f56) / (EP36-∑CP)<14.

8.

11. The optical imaging system according to any one of claims 1 to 8, characterized in that, The plurality of spacer elements further includes a fourth spacer element that is at least partially in contact with the image-side surface of the fourth lens, wherein, The outer diameter D4m of the image side of the fourth spacer element, the inner diameter d4s of the object side of the fourth spacer element, the radius of curvature R9 of the object side of the fifth lens, and the radius of curvature R8 of the image side of the fourth lens satisfy: 0.71≤D4m / R9+d4s / R8≤5.

15.

12. The optical imaging system according to any one of claims 1 to 8, characterized in that, The plurality of spacer elements further includes a fourth spacer element that is at least partially in contact with the image-side surface of the fourth lens; wherein, The inner diameter d4s of the object side of the fourth spacer element, the inner diameter d5m of the image side of the fifth spacer element, the radius of curvature R9 of the object side of the fifth lens, and the radius of curvature R11 of the object side of the sixth spacer element satisfy: -40.80≤(d4s-d5m) / (R9+R11)≤11.

52.

13. The optical imaging system according to any one of claims 1 to 8, characterized in that, The plurality of spacer elements further includes a fourth spacer element that is at least partially in contact with the image-side surface of the fourth lens; wherein, The effective focal length f5 of the fifth lens, the effective focal length f7 of the seventh lens, the spacing EP45 between the fourth and fifth spacers on the optical axis, and the spacing EP56 between the fifth and sixth spacers on the optical axis satisfy: 4.8 < (f5 - f7) / (EP45 + EP56) ≤ 11.

30.

14. The optical imaging system according to any one of claims 1 to 8, characterized in that, The plurality of spacers further includes a first spacer element that at least partially contacts the image-side surface of the first lens, a second spacer element that at least partially contacts the image-side surface of the second lens, a third spacer element that at least partially contacts the image-side surface of the third lens, and a fourth spacer element that at least partially contacts the image-side surface of the fourth lens; wherein, The maximum height L of the lens barrel along the optical axis, the distance TD from the object side of the first lens to the image side of the seventh lens along the optical axis, the sum of the air gaps ∑AT between any two adjacent lenses from the first lens to the seventh lens along the optical axis, and the sum of the maximum thicknesses ∑CP from the first spacer element to the sixth spacer element along the optical axis satisfy: 5.7 < (L + TD) / (∑AT - ∑CP) ≤ 12.

11.

15. The optical imaging system according to any one of claims 1 to 8, characterized in that, The inner diameter d5m of the image side of the fifth spacer element, the inner diameter d6m of the image side of the sixth spacer element, the center thickness CT5 of the fifth lens on the optical axis, and the center thickness CT6 of the sixth lens on the optical axis satisfy: 6.31≤(d5m+d6m) / (CT5+CT6)≤10.

11.

16. The optical imaging system according to any one of claims 1 to 8, characterized in that, The plurality of spacer elements further includes a fourth spacer element that is at least partially in contact with the image-side surface of the fourth lens, wherein, The outer diameter D4m of the image side of the fourth spacer element, the inner diameter d4s of the object side of the fourth spacer element, the center thickness CT4 of the fourth lens on the optical axis, and the air gap T45 between the fourth lens and the fifth lens on the optical axis satisfy: 1.30≤(D4m-d4s) / (CT4-T45)<5.

0.

17. The optical imaging system according to any one of claims 1 to 8, characterized in that, The effective focal length f of the optical imaging system, the aperture number Fno of the optical imaging system, the outer diameter D0m of the image-side end of the lens barrel near the image side, and the inner diameter d0m of the image-side end of the lens barrel near the image side satisfy: 11.37≤f×Fno / (D0m-d0m)≤43.

04.

18. The optical imaging system according to any one of claims 1 to 8, characterized in that, The maximum height L of the lens barrel along the optical axis, the outer diameter D0m of the lens barrel at the image side end near the image side, the distance BFL from the image side of the seventh lens to the imaging surface of the optical imaging system on the optical axis, and the sum of the center thicknesses ∑CT of the first lens to the seventh lens on the optical axis satisfy: 6.2 < (L-D0m) / (BFL-∑CT) < 18.

8.

19. The optical imaging system according to any one of claims 1 to 8, characterized in that, The maximum height L of the lens barrel along the optical axis and the effective focal length f of the optical imaging system satisfy the condition: 0.7 < L / f ≤ 0.80.

Images