Optical imaging system

Abstract

The application discloses an optical imaging system, which comprises a lens barrel, an optical lens group and a spacer group arranged in the lens barrel; the optical lens group is sequentially arranged from an object side to an image side along an optical axis and comprises a first lens with optical power, a second lens with optical power, a third lens with optical power, a fourth lens with optical power, a fifth lens with optical power, a sixth lens with optical power and a seventh lens with optical power; the spacer group comprises a first spacer arranged on an image side surface of the first lens and in contact with the image side surface of the first lens; wherein the optical imaging system has seven lenses with optical power; a half of a maximum field of view angle Semi-FOV of the optical imaging system satisfies 60°< Semi-FOV < 80°; an aperture number Fno of the optical imaging system satisfies Fno < 1.8; a total effective focal length f of the optical imaging system, an inner diameter d0s of an object side end surface of the lens barrel and an inner diameter d1s of an object side surface of the first spacer satisfy 0.2 < f / (d0s-d1s) < 0.5.

Description

Technical Field

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

[0002] With the development of science and technology, wide-angle lenses have been widely used in the fields of mobile phones, security monitoring, automobiles, unmanned aerial vehicles and the like due to their characteristics of wide shooting coverage and being more capable of highlighting the details and layering of scenery.

[0003] In order to achieve the wide-angle characteristic, an optical imaging system is designed into a structural form of seven lenses, wherein the front-end lens is closely related to the amount of incident light of the optical imaging system. However, the existing optical imaging system has a serious stray light problem while satisfying a large amount of incident light, thereby affecting the imaging effect of the optical imaging system. Summary of the Invention

[0004] In one aspect of the present application, there is provided such an optical imaging system, which comprises a lens barrel, an optical lens group and a spacer group disposed in the lens barrel. The optical lens group comprises a first lens having power, a second lens having power, a third lens having power, a fourth lens having power, a fifth lens having power, a sixth lens having power and a seventh lens having power, which are sequentially arranged along an optical axis from an object side to an image side. The spacer group comprises a first spacer disposed on an image side surface of the first lens and in contact with the image side surface of the first lens. Wherein, the number of lenses with power in the optical imaging system is seven; half of the maximum field of view of the optical imaging system Semi-FOV satisfies: 60°<Semi-FOV<80°; the f-number Fno of the optical imaging system satisfies: Fno<1.8; the total effective focal length f of the optical imaging system, the inner diameter d0s of the object side end surface of the lens barrel and the inner diameter d1s of the object side surface of the first spacer satisfy: 0.2<f / (d0s-d1s)<0.5.

[0005] According to an exemplary embodiment of the present application, the entrance pupil diameter EPD of the optical imaging system, the inner diameter d1m of the image side surface of the first spacer and the outer diameter D1m of the image side surface of the first spacer satisfy: 3<(D1m-d1m) / EPD<5.

[0006] According to an exemplary embodiment of the present application, the spacer group further comprises a second spacer disposed on an image side surface of the second lens and in contact with the image side surface of the second lens. Wherein, the effective focal length f1 of the first lens, the effective focal length f2 of the second lens, the inner diameter d2s of the object side surface of the second spacer and the inner diameter d2m of the image side surface of the second spacer satisfy: -3<d2s / f1+d2m / f2<0.

[0007] According to an exemplary embodiment of this application, the spacer assembly further includes a second spacer disposed on and in contact with the image-side surface of the second lens, and a second auxiliary spacer disposed on and in contact with the image-side surface of the second spacer. The maximum thickness CP2 of the second spacer satisfies: CP2 > 0.3 mm; the effective full aperture DT31 of the light-transmitting portion of the object-side surface of the third lens, the inner diameter d2bm of the image-side surface of the second auxiliary spacer, and the outer diameter D2bm of the image-side surface of the second auxiliary spacer satisfy: 2 < (D2bm - d2bm) / DT31 < 2.5.

[0008] According to an exemplary embodiment of this application, the spacer assembly further includes a third spacer disposed on and in contact with the image-side surface of the third lens. The center thickness CT3 of the third lens along the optical axis, the refractive index N3 of the third lens, and the inner diameter d3s of the object-side surface of the third spacer satisfy: 5 <d3s / CT3×N3<6。

[0009] According to an exemplary embodiment of this application, the spacer assembly further includes a second spacer disposed on and in contact with the image-side surface of the second lens, and a third spacer disposed on and in contact with the image-side surface of the third lens. The effective focal length f3 of the third lens, the inner diameter d2m of the image-side surface of the second spacer, and the inner diameter d3s of the object-side surface of the third spacer satisfy: -0.5 < (d2m - d3s) / f3 < 1.5.

[0010] According to an exemplary embodiment of this application, the spacer assembly further includes a fourth spacer disposed on and in contact with the image-side surface of the fourth lens. The air gap T45 between the fourth and fifth lenses on the optical axis satisfies the following condition: 0 <CP4 / T45<0.8。

[0011] According to an exemplary embodiment of this application, the spacer assembly further includes a fourth spacer disposed on and in contact with the image-side surface of the fourth lens. The effective focal length f4 of the fourth lens, the effective focal length f5 of the fifth lens, the inner diameter d4s of the object-side surface of the fourth spacer, and the outer diameter D4m of the image-side surface of the fourth spacer satisfy: -0.3 < (D4m - d4s) / (f4 + f5) < 0.

[0012] According to an exemplary embodiment of the present application, the spacer group further comprises a fifth spacer disposed on the image side surface of the fifth lens and in contact with the image side surface of the fifth lens. Wherein, the effective full aperture DT52 of the light-transmitting portion of the image side surface of the fifth lens and the outer diameter D5s of the object side surface of the fifth spacer satisfy: 2<D5s / DT52<3.2; the effective full aperture DT61 of the light-transmitting portion of the object side surface of the sixth lens and the outer diameter D5m of the image side surface of the fifth spacer satisfy: 2<D5m / DT61≤3.2.

[0013] According to an exemplary embodiment of the present application, the spacer group further comprises a sixth spacer disposed on the image side surface of the sixth lens and in contact with the image side surface of the sixth lens. Wherein, the inner diameter d6s of the object side surface of the sixth spacer, the outer diameter D6m of the image side surface of the sixth spacer and the maximum thickness CP6 of the sixth spacer satisfy: 1.5<(D6m-d6s) / CP6<3.

[0014] According to an exemplary embodiment of the present application, the spacer group further comprises a sixth spacer disposed on the image side surface of the sixth lens and in contact with the image side surface of the sixth lens, and a sixth auxiliary spacer disposed on the image side surface of the sixth spacer and in contact with the image side surface of the sixth spacer. Wherein, the effective focal length f6 of the sixth lens and the effective focal length f7 of the seventh lens satisfy: -1<f6 / f7<-0.5; the air gap T67 between the sixth lens and the seventh lens on the optical axis and the inner diameter d6bm of the image side surface of the sixth auxiliary spacer satisfy: 5<d6bm / T67<6.

[0015] According to an exemplary embodiment of the present application, the spacer group further comprises a sixth spacer disposed on the image side surface of the sixth lens and in contact with the image side surface of the sixth lens. Wherein, the curvature radius R13 of the object side surface of the seventh lens and the curvature radius R14 of the image side surface of the seventh lens satisfy: -0.5<R13 / R14≤0; the effective focal length f7 of the seventh lens, the inner diameter d0m of the image side end surface of the lens barrel and the inner diameter d6m of the image side surface of the sixth spacer satisfy: 0.5<(d0m-d6m) / f7<1.

[0016] According to an exemplary embodiment of the present application, the inner diameter d0s of the object side end surface of the lens barrel and the inner diameter dsmin of the object side surface of the spacer having the smallest inner diameter of the object side surface in the spacer group satisfy: 2.8<d0s / dsmin<3.8.

[0017] In the present application, by enabling the optical imaging system to satisfy "60° < Semi-FOV < 80°" and "Fno < 1.8", while the optical imaging system has a large light input amount, it is favorable for the optical imaging system to obtain a larger field of view range, no large distortion is generated, and a large picture spatial sense can be obtained during shooting without excessive distortion. However, in this case, the large light input amount of the optical imaging system will bring about certain stray light problems. Therefore, by controlling the ratio of the total effective focal length of the optical imaging system to the difference between the inner diameter of the object-side end surface of the lens barrel and the inner diameter of the object-side surface of the first spacer, the difference between the inner diameter of the object-side end surface of the lens barrel and the inner diameter of the object-side surface of the first spacer can be constrained within a reasonable range, ensuring that the first spacer can effectively block excess light outside the field of view, reduce stray light, and effectively control the refraction angle of light, so that the traveling trend of light in the system is relatively uniform, and avoiding the problem that off-field light is too steep and enters the non-light-transmitting portion of the first lens to generate internal reflection stray light. Brief Description of Drawings

[0018] Other features, objects and advantages of the present application will become more apparent upon reading the following detailed description of non-limiting embodiments with reference to the accompanying drawings, wherein:

[0019] Figure 1 shows a parameter marking diagram of an optical imaging system according to the present application;

[0020] Figure 2 shows a structural schematic diagram of an optical imaging system according to embodiment 1 of the present application;

[0021] Figure 3 shows a structural schematic diagram of an optical imaging system according to embodiment 2 of the present application;

[0022] Figure 4 shows a structural schematic diagram of an optical imaging system according to embodiment 3 of the present application;

[0023] Figures 5A to 5C respectively show an axial chromatic aberration curve, an astigmatism curve and a distortion curve of the optical imaging system of embodiment 1, 2 or 3 of the present application;

[0024] Figure 6 shows a structural schematic diagram of an optical imaging system according to embodiment 4 of the present application;

[0025] Figure 7 shows a structural schematic diagram of an optical imaging system according to embodiment 5 of the present application;

[0026] Figure 8 shows a structural schematic diagram of an optical imaging system according to embodiment 6 of the present application;

[0027] Figures 9A to 9CThe on-axis chromatic aberration curves, astigmatism curves, and distortion curves of the optical imaging systems of embodiments 4, 5, or 6 of this application are shown respectively.

[0028] Figure 10 A schematic diagram of the structure of an optical imaging system according to Embodiment 7 of this application is shown;

[0029] Figure 11 A schematic diagram of the structure of an optical imaging system according to Embodiment 8 of this application is shown;

[0030] Figure 12 A schematic diagram of the structure of an optical imaging system according to Embodiment 9 of this application is shown;

[0031] Figures 13A to 13C The on-axis chromatic aberration curves, astigmatism curves, and distortion curves of the optical imaging systems of embodiments 7, 8, or 9 of this application are shown respectively.

[0032] Figure 14A The actual image captured by the optical imaging system when f / (d0s-d1s)=1.91 is shown;

[0033] Figure 14B The actual image captured by the optical imaging system when f / (d0s-d1s) = 0.037 is shown;

[0034] Figure 14C The actual image captured by the optical imaging system when f / (d0s-d1s) = 0.28 is shown;

[0035] Figure 15A The ray diagram of the optical imaging system is shown when f / (d0s-d1s)=1.91;

[0036] Figure 15B The ray diagram of the optical imaging system is shown when f / (d0s-d1s) = 0.037;

[0037] Figure 16A A stray light simulation diagram is shown when the optical imaging system satisfies f / (d0s-d1s)=1.91; and

[0038] Figure 16B A stray light simulation diagram is shown when the optical imaging system satisfies f / (d0s-d1s)=0.037. Detailed Implementation

[0039] 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.

[0040] 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.

[0041] 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.

[0042] 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 image plane is called the image-side surface of the lens.

[0043] It should also be understood that the terms "comprising" and / or "having," 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 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.

[0044] 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.

[0045] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0046] Figure 1 This is a parameter annotation diagram of an optical imaging system according to an exemplary embodiment of this application. (Reference) Figure 1d1s represents the inner diameter of the object-side surface of the first spacer, d1m represents the inner diameter of the image-side surface of the first spacer, D1m represents the outer diameter of the image-side surface of the first spacer, d2s represents the inner diameter of the object-side surface of the second spacer, d2m represents the inner diameter of the image-side surface of the second spacer, d2bm represents the inner diameter of the image-side surface of the second auxiliary spacer, D2bm represents the outer diameter of the image-side surface of the second auxiliary spacer, d3s represents the inner diameter of the object-side surface of the third spacer, d4s represents the inner diameter of the object-side surface of the fourth spacer, D4m represents the outer diameter of the image-side surface of the fourth spacer, D5 s represents the outer diameter of the object side of the fifth spacer, D5m represents the outer diameter of the image side of the fifth spacer, d6s represents the inner diameter of the object side of the sixth spacer, d6m represents the inner diameter of the image side of the sixth spacer, D6m represents the outer diameter of the image side of the sixth spacer, d6bm represents the inner diameter of the image side of the sixth auxiliary spacer, d0s represents the inner diameter of the object side end face of the lens barrel, d0m represents the inner diameter of the image side end face of the lens barrel, CP2 represents the maximum thickness of the second spacer, CP4 represents the maximum thickness of the fourth spacer, and CP6 represents the maximum thickness of the sixth spacer.

[0047] refer to Figures 2 to 4 , Figures 6 to 8 as well as Figures 10 to 12 The first aspect of this application provides an optical imaging system that may include an optical lens group, which may include 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. An air gap may exist between any two adjacent lenses in the first to seventh lenses.

[0048] In an exemplary embodiment, the first lens may have negative optical power.

[0049] In an exemplary embodiment, the second lens may have positive optical power.

[0050] In an exemplary embodiment, the third lens may have positive optical power.

[0051] In an exemplary embodiment, the fourth lens may have negative optical power.

[0052] In an exemplary embodiment, the fifth lens may have positive optical power.

[0053] In an exemplary embodiment, the sixth lens may have negative optical power.

[0054] In an exemplary embodiment, the seventh lens may have positive optical power.

[0055] In an exemplary embodiment, the object-side surface of the first lens can be convex or concave, and the image-side surface can be concave.

[0056] In an exemplary embodiment, the object-side surface of the second lens can be convex, and the image-side surface can be concave.

[0057] In an exemplary embodiment, the object-side surface of the third lens can be convex, and the image-side surface can be convex.

[0058] In an exemplary embodiment, the object-side surface of the fourth lens can be convex, and the image-side surface can be concave.

[0059] In an exemplary embodiment, the object-side surface of the fifth lens can be convex, and the image-side surface can also be convex.

[0060] In an exemplary embodiment, the object-side surface of the sixth lens can be concave, and the image-side surface can be convex.

[0061] In an exemplary embodiment, the object-side surface of the seventh lens can be convex, and the image-side surface can also be convex.

[0062] In an exemplary embodiment, the optical imaging system may have seven lenses with optical power.

[0063] In an exemplary embodiment, the optical imaging system may further include an aperture stop. The aperture stop may be disposed between the second lens and the third lens.

[0064] In an exemplary embodiment, the optical imaging system may further include a group of spacers, which may include one or more of a first spacer, a second spacer, a second auxiliary spacer, a third spacer, a fourth spacer, a fifth spacer, a sixth spacer, and a sixth auxiliary spacer. The first spacer may be positioned on the image-side surface of a first lens and at least partially in contact with it. The second spacer may be positioned on the image-side surface of a second lens and at least partially in contact with it. The second auxiliary spacer may be positioned on the image-side surface of the second spacer and at least partially in contact with it. The third spacer may be positioned on the image-side surface of a third lens and at least partially in contact with it. The fourth spacer may be positioned on the image-side surface of a fourth lens and at least partially in contact with it. The fifth spacer may be positioned on the image-side surface of a fifth lens and at least partially in contact with it. The sixth spacer may be positioned on the image-side surface of a sixth lens and at least partially in contact with it. The sixth auxiliary spacer may be positioned on the image-side surface of the sixth spacer and at least partially in contact with it. The proper use of spacers can effectively avoid stray light risks, reduce interference with image quality, and thus improve the imaging quality of optical imaging systems.

[0065] In an exemplary embodiment, the optical imaging system may further comprise a lens barrel, and the optical lens group and the spacer group are disposed in the lens barrel. The lens barrel may comprise an object-side end surface, an image-side end surface, an outer annular surface and an inner annular surface, wherein the end surface of the lens barrel closest to the object side is the object-side end surface of the lens barrel, and the end surface of the lens barrel closest to the image side is the image-side end surface of the lens barrel; in a direction perpendicular to the optical axis, the surface of the lens barrel farthest from the optical axis is the outer annular surface, and the surface of the lens barrel closest to the optical axis is the inner annular surface. The inner annular surface of the lens barrel is stepped.

[0066] In an exemplary embodiment, half of the maximum field angle of the optical imaging system, Semi-FOV, may satisfy: 60°<Semi-FOV<80°. By way of example, 65°<Semi-FOV<72°. Reasonably configuring half of the maximum field angle of the optical imaging system is beneficial for the optical imaging system to obtain a larger field of view without causing large distortion, and a large sense of picture space can be obtained during shooting without excessive distortion.

[0067] In an exemplary embodiment, the f-number Fno of the optical imaging system may satisfy: Fno<1.8. By way of example, 1.6<Fno<1.8. Reasonably configuring the f-number of the optical imaging system enables the optical imaging system to have a large amount of incident light, ensuring that the optical imaging system can achieve a relatively clear shooting effect in dark environments such as at night.

[0068] In an exemplary embodiment, the total effective focal length f of the optical imaging system, the inner diameter d0s of the object-side end surface of the lens barrel, and the inner diameter d1s of the object-side surface of the first spacer may satisfy: 0.2<f / (d0s-d1s)<0.5. When the optical imaging system satisfies "60°<Semi-FOV<80°" and "Fno<1.8", the large amount of incident light of the optical imaging system will bring about certain stray light problems. Therefore, by controlling the ratio of the total effective focal length of the optical imaging system to the difference between the inner diameter of the object-side end surface of the lens barrel and the inner diameter of the object-side surface of the first spacer, the difference between the inner diameter of the object-side end surface of the lens barrel and the inner diameter of the object-side surface of the first spacer can be constrained within a reasonable range, ensuring that the first spacer can effectively block excess light outside the field of view and reduce stray light. Meanwhile, the refraction angle of light can be effectively controlled, so that the propagation trend of light in the system is relatively uniform, and the problem that the outer field of view light enters the non-light-transmitting portion of the first lens too steeply to generate internal reflection stray light is avoided.

[0069] In the present application, f / (d0s-d1s) is constrained within the range of 0.2 to 0.5, which can well balance the propagation trend of light and reduce stray light; meanwhile, it avoids the problem of excessive difference in aperture between the first lens and the lens at the rear stop position (e.g., the second lens and the third lens) caused by an excessive inner diameter difference between the object-side end surface of the lens barrel and the object-side surface of the first spacer, thereby avoiding the problems that the first lens has a large curvature due to the excessive aperture difference and stray light is generated when light is reflected to the non-light-transmitting portion of the first lens.

[0070] Table 1 shows the imaging effects of three optical imaging systems (e.g., optical imaging system 1, optical imaging system 2, and optical imaging system 3). Figure 14C It is an actual captured image when optical imaging system 1 satisfies f / (d0s-d1s) = 0.28. Figure 14A It is an actual captured image when optical imaging system 2 satisfies f / (d0s-d1s) = 1.91. Figure 14B It is an actual captured image when optical imaging system 3 satisfies f / (d0s-d1s) = 0.037. Figure 15A It is a ray diagram when optical imaging system 2 satisfies f / (d0s-d1s) = 1.91. Figure 15B It is a ray diagram when optical imaging system 3 satisfies f / (d0s-d1s) = 0.037. Figure 16A It is a stray light simulation diagram when optical imaging system 2 satisfies f / (d0s-d1s) = 1.91. Figure 16B shows a stray light simulation diagram when optical imaging system 3 satisfies f / (d0s-d1s) = 0.037.

[0071] Optical Imaging System 1 Optical Imaging System 2 Optical Imaging System 3 Conditional values f / (d0s-d1s)=0.28 f / (d0s-d1s)=1.91 f / (d0s-d1s)=0.037 Illustration Figure 14C Figure 14A , Figure 15A and Figure 16A Figure 14B , Figure 15B and Figure 16B Imaging effect good Poor Poor

[0072] Table 1

[0073] From Figure 14A , Figure 15A , Figure 16A , it can be seen that the inner diameter difference between the object-side end surface of the lens barrel and the object-side surface of the first spacer is small, the first spacer cannot effectively block stray light in the outer field of view, and optical imaging system 2 has an obvious stray light phenomenon. From Figure 14B , Figure 15B , Figure 16B , it can be seen that the inner diameter difference between the object-side end surface of the lens barrel and the object-side surface of the first spacer is large, and the first lens has a large curvature, large-angle light is reflected to the non-light-transmitting portion of the first lens and generates stray light, and optical imaging system 3 has an obvious stray light phenomenon. From Figure 14C , it can be seen that the stray light phenomenon of optical imaging system 1 is effectively improved. It can be seen that controlling the optical imaging system to satisfy "-0.2<f / (d0s-d1s)<0.5" is helpful to improve the stray light phenomenon and enhance the imaging effect of the optical imaging system.

[0074] In an exemplary embodiment, the entrance pupil diameter EPD of the optical imaging system, the inner diameter d1m of the image side surface of the first spacer and the outer diameter D1m of the image side surface of the first spacer may satisfy: 3<(D1m-d1m) / EPD<5. By controlling the ratio of the difference between the outer diameter and the inner diameter of the image side surface of the first spacer to the entrance pupil diameter of the optical imaging system, the maximum incident angle of light when entering the system and the refraction angle of light in the first lens can be effectively constrained, which improves the illumination of the outer field of view and the size of the imaging surface of the optical imaging system; meanwhile, it can also limit the inner and outer diameters of the image side surface of the first spacer, improve the assembly stability of the optical imaging system, reduce the stray light phenomenon, and thereby improve the imaging quality and reliability quality of the optical imaging system.

[0075] In an exemplary embodiment, the effective focal length f1 of the first lens, the effective focal length f2 of the second lens, the inner diameter d2s of the object side surface of the second spacer and the inner diameter d2m of the image side surface of the second spacer may satisfy: -3<d2s / f1+d2m / f2<0. By controlling the above conditional expression, the effective focal lengths of the first lens and the second lens can be constrained, thereby limiting the surface shapes of the first lens and the second lens, and ensuring that light transmits along a predetermined path; meanwhile, it can also constrain the inner diameters of the object side surface and the image side surface of the second spacer, ensuring that the second spacer can effectively block stray light that may pass through the third lens, thereby improving the imaging quality of the optical imaging system, and the size of the second spacer can indirectly limit the outer diameter of the third lens, thereby reducing the total weight of the optical imaging system.

[0076] In an exemplary embodiment, the maximum thickness CP2 of the second spacer may satisfy: CP2>0.3mm; the effective full aperture DT31 of the light-transmitting portion of the object side surface of the third lens, the inner diameter d2bm of the image side surface of the second auxiliary spacer and the outer diameter D2bm of the image side surface of the second auxiliary spacer may satisfy: 2<(D2bm-d2bm) / DT31<2.5. By way of example, 0.3mm<CP2<1.0mm. By controlling the ratio of the difference between the outer diameter and the inner diameter of the image side surface of the second auxiliary spacer to the effective full aperture of the light-transmitting portion of the object side surface of the third lens, it is beneficial to ensure that imaging light refracts along a predetermined path at the rear end of the optical imaging system, so as to control the image height of each field of view to a required position; meanwhile, it can also indirectly constrain the outer diameters of the second lens and the third lens, and improve the formability of the second lens and the third lens.

[0077] In an exemplary embodiment, the central thickness CT3 of the third lens on the optical axis, the refractive index N3 of the third lens, and the inner diameter d3s of the object side surface of the third spacer may satisfy: 5<d3s / CT3×N3<6. By controlling the above conditional expression, the smoothness and moldability of the effective surface of the third lens (for example, the aspheric surface for transmitting imaging light) can be improved, ensuring that the third lens does not have a surface shape with large curvature, improving the stability during assembly of the third lens, reducing the risk of assembly deformation, thereby improving the imaging quality of the optical imaging system.

[0078] In an exemplary embodiment, the effective focal length f3 of the third lens, the inner diameter d2m of the image side surface of the second spacer, and the inner diameter d3s of the object side surface of the third spacer may satisfy: -0.5<(d2m-d3s) / f3<1.5. By controlling the ratio of the difference between the inner diameters of the image side surface of the second spacer and the object side surface of the third spacer to the effective focal length of the third lens, the propagation trend of light after exiting the second lens and entering the third lens can be effectively constrained, and at the same time, the quantity and energy of light within the field of view can be guaranteed. The second spacer and the third spacer block part of the light that may enter the non-light-transmitting portion of the lens, effectively weakening the energy of stray light spots, and ensuring that the optical imaging system has good imaging quality.

[0079] In an exemplary embodiment, the air gap T45 between the fourth lens and the fifth lens on the optical axis and the maximum thickness CP4 of the fourth spacer may satisfy: 0<CP4 / T45<0.8. By controlling the ratio of the maximum thickness of the fourth spacer to the air gap between the fourth lens and the fifth lens on the optical axis, the edge gap between the fourth lens and the fifth lens can be constrained, avoiding the problems of excessive thickness of the fourth spacer and easy generation of stray light on the inner surface of the fourth spacer caused by an excessively large edge gap; meanwhile, it can also ensure that the fourth lens is easier to mold and reduce the risk of stray light caused by weld lines.

[0080] In an exemplary embodiment, the effective focal length f4 of the fourth lens, the effective focal length f5 of the fifth lens, the inner diameter d4s of the object side surface of the fourth spacer, and the outer diameter D4m of the image side surface of the fourth spacer may satisfy: -0.3<(D4m-d4s) / (f4+f5)<0. By controlling the above conditional expression, the angle of the inner inclined surface of the fourth spacer and the effective focal lengths of the fourth lens and the fifth lens can be constrained, thereby limiting the propagation direction of light and avoiding the problem of internal reflection stray light caused by reflection from the inner inclined surface of the fourth spacer.

[0081] In an exemplary embodiment, the effective full aperture DT52 of the light-transmitting portion of the image-side surface of the fifth lens and the outer diameter D5s of the object-side surface of the fifth spacer may satisfy: 2 < D5s / DT52 < 3.2; the effective full aperture DT61 of the light-transmitting portion of the object-side surface of the sixth lens and the outer diameter D5m of the image-side surface of the fifth spacer may satisfy: 2 < D5m / DT61 ≤ 3.2. By controlling the ratio of the outer diameter of the object-side surface of the fifth spacer to the effective full aperture of the light-transmitting portion of the image-side surface of the fifth lens, and the ratio of the outer diameter of the image-side surface of the fifth spacer to the effective full aperture of the light-transmitting portion of the object-side surface of the sixth lens, the heights of the non-light-transmitting portions of the lenses on both object and image sides of the fifth spacer can be made similar, and the non-light-transmitting portion of the sixth lens is substantially completely shielded by the fifth spacer, thereby ensuring that the fifth spacer can effectively intercept stray light that may enter the sixth lens, and improving the imaging quality of the optical imaging system.

[0082] In an exemplary embodiment, the inner diameter d6s of the object-side surface of the sixth spacer, the outer diameter D6m of the image-side surface of the sixth spacer and the maximum thickness CP6 of the sixth spacer may satisfy: 1.5 < (D6m-d6s) / CP6 < 3. By controlling the above conditional expression, the maximum thickness of the sixth spacer can be constrained within a reasonable range, improving the molding stability of the sixth spacer; meanwhile, it can also indirectly limit the edge thicknesses of the sixth lens and the seventh lens, ensure the processability and thickness-to-thickness ratio of the molds for the two lenses, thereby improving the surface profile stability of the two lenses after molding and enhancing the imaging quality of the optical imaging system.

[0083] In an exemplary embodiment, the effective focal length f6 of the sixth lens and the effective focal length f7 of the seventh lens may satisfy: -1 < f6 / f7 < -0.5; the air gap T67 between the sixth lens and the seventh lens on the optical axis and the inner diameter d6bm of the image-side surface of the sixth auxiliary spacer may satisfy: 5 < d6bm / T67 < 6. By controlling the ratio of the effective focal lengths of the sixth lens and the seventh lens, the smoothness and moldability of the effective surfaces (for example, aspheric surfaces used for transmitting imaging light) of the two lenses can be improved; meanwhile, in combination with limiting the ratio of the inner diameter of the image-side surface of the sixth auxiliary spacer to the air gap between the sixth lens and the seventh lens on the optical axis, cross-shaped stray light and trailing stray light reflected by the inner surface of the sixth auxiliary spacer can be reduced, thereby improving the imaging quality of the optical imaging system.

[0084] In an exemplary embodiment, the radius of curvature R13 of the object-side surface of the seventh lens and the radius of curvature R14 of the image-side surface of the seventh lens may satisfy: -0.5 < R13 / R14 ≤ 0; the effective focal length f7 of the seventh lens, the inner diameter d0m of the image-side end surface of the lens barrel and the inner diameter d6m of the image-side surface of the sixth spacer may satisfy: 0.5 < (d0m - d6m) / f7 < 1. As an example, -0.1 < R13 / R14 ≤ 0. By controlling the ratio of the radius of curvature of the object-side surface to that of the image-side surface of the seventh lens, the smoothness and moldability of the effective surface (e.g., the aspheric surface for transmitting imaging light) of the seventh lens can be improved, and the imaging quality of the optical imaging system can be enhanced; meanwhile, by limiting the ratio of the difference between the inner diameters of the image-side end surface of the lens barrel and the image-side surface of the sixth spacer to the effective focal length of the seventh lens, the light blocking efficiency of the sixth spacer can be effectively improved, stray light caused by light hitting the image-side end surface of the lens barrel can be avoided, the difference between the outer diameter and the inner diameter of the sixth spacer can be indirectly constrained, and problems such as baking deformation and assembly eccentricity of the sixth spacer can be reduced, thereby reducing the problems of light leakage and stray light caused by the deformation and assembly eccentricity of the sixth spacer.

[0085] In an exemplary embodiment, the inner diameter d0s of the object-side end surface of the lens barrel and the inner diameter dsmin of the object-side surface of the spacer having the smallest inner diameter of the object-side surface in the spacer group may satisfy: 2.8 < d0s / dsmin < 3.8. By controlling the above conditional expression, the light transmission through the sharp corner of the lens barrel outlet can be blocked, and the spacer with the smallest inner diameter of the object-side surface can intercept the light transmitted from the straight position of the outlet, avoiding the generation of flocculent stray light; meanwhile, the size of the inner diameter of the lens barrel outlet can be constrained, ensuring that the position does not intercept chief rays, and improving the imaging quality of the optical imaging system. As an example, the inner diameter of the object-side surface of the second spacer is smaller than the inner diameter of the object-side surface of any other spacer in the spacer group except the second spacer; or, the inner diameter of the object-side surface of the second auxiliary spacer is smaller than the inner diameter of the object-side surface of any other spacer in the spacer group except the second auxiliary spacer.

[0086] The optical imaging system according to the above embodiments of the present application may employ seven lenses and at least one spacer. By reasonably distributing the parameters of each lens and each spacer, the stray light risk of the optical imaging system can be reduced, and the imaging quality, assembly stability and assembly yield of the optical imaging system can be improved.

[0087] In the embodiment of the present application, at least one of the surfaces of each of the first lens to the seventh lens is an aspheric surface. An aspheric lens is characterized in that: the curvature changes continuously from the center of the lens to the periphery of the lens. Different from a spherical lens which has a constant curvature from the center of the lens to the periphery of the lens, an aspheric lens has better curvature radius characteristics, and has the advantages of improving distortion aberration and improving astigmatism aberration. After adopting the aspheric lens, the aberration occurring during imaging can be eliminated as much as possible, thereby improving the imaging quality. Optionally, both the object-side surface and the image-side surface of each of the first lens to the seventh lens are aspheric surfaces.

[0088] A second aspect of the present application provides such an optical imaging system, which includes a lens barrel, an optical lens group and a spacer group disposed in the lens barrel. The optical lens group includes a first lens having power, a second lens having power, a third lens having power, a fourth lens having power, a fifth lens having power, a sixth lens having power and a seventh lens having power sequentially arranged along an optical axis from an object side to an image side. The spacer group includes a first spacer disposed on the image-side surface of the first lens and in contact with the image-side surface of the first lens. The number of lenses with power in the optical imaging system is seven.

[0089] Wherein, half of the maximum field of view Semi-FOV of the optical imaging system can satisfy: 60°<Semi-FOV<80°; the f-number Fno of the optical imaging system satisfies: Fno<1.8; the entrance pupil diameter EPD of the optical imaging system, the inner diameter d1m of the image-side surface of the first spacer, and the outer diameter D1m of the image-side surface of the first spacer satisfy: 3<(D1m-d1m) / EPD<5. By enabling the optical imaging system to satisfy "60°<Semi-FOV<80°" and "Fno<1.8", the present application is beneficial for the optical imaging system to obtain a larger field of view while the optical imaging system has a large amount of incident light, and does not produce large distortion. When shooting, a large sense of picture space can be obtained without excessive distortion. However, in this case, the large amount of incident light of the optical imaging system will bring about a certain stray light problem. Therefore, by controlling the ratio of the difference between the outer diameter and the inner diameter of the image-side surface of the first spacer to the entrance pupil diameter of the optical imaging system, the maximum incident angle of light when entering the system and the refraction angle of light in the first lens can be effectively constrained, so as to improve the outer field illuminance and the imaging surface size of the optical imaging system; at the same time, the inner and outer diameters of the image-side surface of the first spacer can also be limited, so as to improve the assembly stability of the optical imaging system, improve the stray light phenomenon, and further improve the imaging quality and reliability quality of the optical imaging system.

[0090] Those skilled in the art will understand that, without departing from the technical solutions claimed in this application, the number of lenses and spacers constituting the optical imaging system can be changed to obtain the various results and advantages described in this specification.

[0091] Specific embodiments of the optical imaging system applicable to the above-described embodiments are further described below with reference to the accompanying drawings.

[0092] Example 1

[0093] The following is for reference Figure 2 An optical imaging system according to Embodiment 1 of this application is described.

[0094] like Figure 2 As shown, the optical imaging system includes a lens barrel P0 and an optical lens group and a spacer group disposed within the lens barrel P0. The optical lens group, arranged sequentially along the optical axis 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, and a seventh lens E7. An aperture stop STO is disposed between the second lens E2 and the third lens E3.

[0095] The first lens E1 has negative optical power, with its object-side surface S1 being concave and its image-side surface S2 being concave. The second lens E2 has positive 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 convex. 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 convex. The sixth lens E6 has negative optical power, with its object-side surface S11 being concave and its image-side surface S12 being convex. The seventh lens E7 has positive optical power, with its object-side surface S13 being convex and its image-side surface S14 being convex. An optical element, such as a filter, may also be disposed between the seventh lens E7 and the imaging surface S17. This optical element has an object-side surface S15 (not shown) and an image-side surface S16 (not shown). Light from the object passes sequentially through surfaces S1 to S16 and is finally imaged onto imaging surface S17 (not shown).

[0096] The spacer assembly may include a first spacer P1, a second spacer P2, a third spacer P3, a fourth spacer P4, a fifth spacer P5, a sixth spacer P6, and a sixth auxiliary spacer P6b. The spacers can block excess light from entering the next lens during the imaging process, while also allowing the lens to better support the lens barrel P0, thus enhancing the structural stability of the optical imaging system.

[0097] Table 2 shows the basic parameters of the optical imaging system of Example 1, where the units for radius of curvature, thickness / distance, focal length, and effective half-aperture are all millimeters (mm).

[0098]

[0099] Table 2

[0100] In this embodiment, the total effective focal length f of the optical imaging system is 2.19 mm. The semi-FOV (half of the maximum field of view) of the optical imaging system is 68.70°. The aperture number Fno of the optical imaging system is 1.79.

[0101] In this embodiment, 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:

[0102]

[0103] Where x is the distance vector from the vertex of the aspherical surface at a height of 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 2 above); k is the conic coefficient; Ai is the i-th order correction coefficient of the aspherical surface. Table 3 gives the higher-order coefficients A4, A6, A8, A14 that can be used for each aspherical surface 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 .

[0104]

[0105]

[0106] Table 3

[0107] Example 2

[0108] The following is for reference Figure 3 An optical imaging system according to Embodiment 2 of this application is described.

[0109] like Figure 3As shown, the optical imaging system includes a lens barrel P0 and an optical lens group and a spacer group disposed within the lens barrel P0. The structure of the optical lens group is the same as that of the optical lens group in Embodiment 1. The spacer group includes a first spacer P1, a second spacer P2, a second auxiliary spacer P2b, a third spacer P3, a fourth spacer P4, a fifth spacer P5, a sixth spacer P6, and a sixth auxiliary spacer P6b.

[0110] The structure of the optical lens group in this embodiment is the same as that of the optical lens group in Embodiment 1. That is, the basic parameter table of the optical imaging system in this embodiment is the same as that in Table 2, and the aspherical coefficient table is the same as that in Table 3. The difference between this embodiment and Embodiment 1 is that the structural dimensions of at least some of the components in the lens barrel P0 and the spacer assembly are different.

[0111] Example 3

[0112] The following is for reference Figure 4 An optical imaging system according to Embodiment 3 of this application is described.

[0113] like Figure 4 As shown, the optical imaging system includes a lens barrel P0 and an optical lens assembly and a spacer assembly disposed within the lens barrel P0. The structure of the optical lens assembly is the same as that of the optical lens assembly in Embodiment 1. The spacer assembly includes a first spacer P1, a second spacer P2, a third spacer P3, a third auxiliary spacer P3b, a fourth spacer P4, a fifth spacer P5, a sixth spacer P6, and a sixth auxiliary spacer P6b.

[0114] The structure of the optical lens group in this embodiment is the same as that of the optical lens group in Embodiment 1. That is, the basic parameter table of the optical imaging system in this embodiment is the same as that in Table 2, and the aspherical coefficient table is the same as that in Table 3. The difference between this embodiment and Embodiment 1 is that the structural dimensions of at least some of the components in the lens barrel P0 and the spacer assembly are different.

[0115] Figure 5A The on-axis chromatic aberration curves of the optical imaging systems of Embodiments 1, 2, or 3 are shown, which represent the deflection of the focal point after light of different wavelengths passes through the optical imaging system. Figure 5B Astigmatism curves for the optical imaging systems of Embodiments 1, 2, or 3 are shown, representing the meridional and sagittal image plane curvatures corresponding to different image heights. Figure 5C Distortion curves for the optical imaging systems of Embodiments 1, 2, or 3 are shown, representing the distortion magnitude values ​​corresponding to different image heights. According to... Figures 5A to 5C It can be seen that the optical imaging systems of Examples 1, 2 or 3 can achieve good imaging quality.

[0116] Example 4

[0117] The following is for reference Figure 6 An optical imaging system according to Embodiment 4 of this application is described.

[0118] like Figure 6 As shown, the optical imaging system includes a lens barrel P0 and an optical lens group and a spacer group disposed within the lens barrel P0. The optical lens group, arranged sequentially along the optical axis 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, and a seventh lens E7. An aperture stop STO is disposed between the second lens E2 and the third lens E3.

[0119] The first lens E1 has negative optical power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens E2 has positive 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 convex. 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 convex. The sixth lens E6 has negative optical power, with its object-side surface S11 being concave and its image-side surface S12 being convex. The seventh lens E7 has positive optical power, with its object-side surface S13 being convex and its image-side surface S14 being convex. An optical element, such as a filter, may also be disposed between the seventh lens E7 and the imaging surface S17. The optical element has an object-side surface S15 (not shown) and an image-side surface S16 (not shown). Light from the object passes sequentially through surfaces S1 to S16 and is finally imaged onto imaging surface S17 (not shown).

[0120] The spacer assembly may include a first spacer P1, a second spacer P2, a second auxiliary spacer P2b, a third spacer P3, a fourth spacer P4, a fifth spacer P5, a sixth spacer P6, and a sixth auxiliary spacer P6b. The spacers can block excess light from entering the next lens during the imaging process, while also allowing the lens to better contact the lens barrel P0, thus enhancing the structural stability of the optical imaging system.

[0121] Table 4 shows the basic parameters of the optical imaging system of Example 4, where the units for radius of curvature, thickness / distance, focal length, and effective half-aperture are all millimeters (mm).

[0122]

[0123] Table 4

[0124] In this embodiment, the total effective focal length f of the optical imaging system is 2.20 mm. The semi-FOV (half of the maximum field of view) of the optical imaging system is 68.54°. The aperture number Fno of the optical imaging system is 1.74.

[0125] In this embodiment, the object-side surface and image-side surface of any one of the lenses, from the first lens E1 to the seventh lens E7, are aspherical. Table 5 shows the higher-order coefficients A4, A6, A8, and A6 that can be used for the aspherical surfaces S1-S14 in Embodiment 4. 10 A 12 A 14 A 16 A 18 A 20 A 22 A 24 A 26 A 28 and A 30 .

[0126]

[0127] Table 5

[0128] Example 5

[0129] The following is for reference Figure 7 An optical imaging system according to Embodiment 5 of this application is described.

[0130] like Figure 7 As shown, the optical imaging system includes a lens barrel P0 and an optical lens assembly and a spacer assembly disposed within the lens barrel P0. The structure of the optical lens assembly is the same as that of the optical lens assembly in Embodiment 4. The spacer assembly includes a first spacer P1, a second spacer P2, a second auxiliary spacer P2b, a third spacer P3, a fourth spacer P4, a fifth spacer P5, a sixth spacer P6, and a sixth auxiliary spacer P6b.

[0131] The structure of the optical lens group in this embodiment is the same as that in Embodiment 4. That is, the basic parameter table of the optical imaging system in this embodiment is the same as that in Table 4, and the aspherical coefficient table is the same as that in Table 5. The difference between this embodiment and Embodiment 4 is that the structural dimensions of at least some of the components in the lens barrel P0 and the spacer assembly are different.

[0132] Example 6

[0133] The following is for reference Figure 8 An optical imaging system according to Embodiment 6 of this application is described.

[0134] like Figure 8As shown, the optical imaging system includes a lens barrel P0 and an optical lens assembly and a spacer assembly disposed within the lens barrel P0. The structure of the optical lens assembly is the same as that of the optical lens assembly in Embodiment 4. The spacer assembly includes a first spacer P1, a second spacer P2, a second auxiliary spacer P2b, a third spacer P3, a fourth spacer P4, a fifth spacer P5, a sixth spacer P6, and a sixth auxiliary spacer P6b.

[0135] The structure of the optical lens group in this embodiment is the same as that in Embodiment 4. That is, the basic parameter table of the optical imaging system in this embodiment is the same as that in Table 4, and the aspherical coefficient table is the same as that in Table 5. The difference between this embodiment and Embodiment 4 is that the structural dimensions of at least some of the components in the lens barrel P0 and the spacer assembly are different.

[0136] Figure 9A The on-axis chromatic aberration curves of the optical imaging systems of Embodiments 4, 5, or 6 are shown, which represent the deflection of the focal point after light of different wavelengths passes through the optical imaging system. Figure 9B Astigmatism curves for the optical imaging systems of Examples 4, 5, or 6 are shown, representing the meridional and sagittal image plane curvatures corresponding to different image heights. Figure 9C Distortion curves for the optical imaging systems of Examples 4, 5, or 6 are shown, representing the magnitude of distortion at different image heights. According to... Figures 9A to 9C It can be seen that the optical imaging systems of Examples 4, 5 or 6 can achieve good imaging quality.

[0137] Example 7

[0138] The following is for reference Figure 10 An optical imaging system according to Embodiment 7 of this application is described.

[0139] like Figure 10 As shown, the optical imaging system includes a lens barrel P0 and an optical lens group and a spacer group disposed within the lens barrel P0. The optical lens group, arranged sequentially along the optical axis 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, and a seventh lens E7. An aperture stop STO is disposed between the second lens E2 and the third lens E3.

[0140] The first lens E1 has negative optical power, with its object-side surface S1 being convex and its image-side surface S2 being concave. The second lens E2 has positive 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 convex. 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 convex. The sixth lens E6 has negative optical power, with its object-side surface S11 being concave and its image-side surface S12 being convex. The seventh lens E7 has positive optical power, with its object-side surface S13 being convex and its image-side surface S14 being convex. An optical element, such as a filter, may also be disposed between the seventh lens E7 and the imaging surface S17. The optical element has an object-side surface S15 (not shown) and an image-side surface S16 (not shown). Light from the object passes sequentially through surfaces S1 to S16 and is finally imaged onto imaging surface S17 (not shown).

[0141] The spacer assembly may include a first spacer P1, a second spacer P2, a second auxiliary spacer P2b, a third spacer P3, a fourth spacer P4, a fifth spacer P5, a sixth spacer P6, and a sixth auxiliary spacer P6b. The spacers can block excess light from entering the next lens during the imaging process, while also allowing the lens to better contact the lens barrel P0, thus enhancing the structural stability of the optical imaging system.

[0142] Table 6 shows the basic parameters of the optical imaging system of Example 7, where the units for radius of curvature, thickness / distance, focal length, and effective half-aperture are all millimeters (mm).

[0143]

[0144]

[0145] Table 6

[0146] In this embodiment, the total effective focal length f of the optical imaging system is 2.20 mm. The semi-FOV (half of the maximum field of view) of the optical imaging system is 68.28°. The aperture number Fno of the optical imaging system is 1.71.

[0147] In this embodiment, the object-side surface and image-side surface of any one of the lenses, from the first lens E1 to the seventh lens E7, are aspherical. Table 7 shows the higher-order coefficients A4, A6, A8, and A6 that can be used for the aspherical surfaces S1-S14 in Embodiment 7. 10 A 12 A 14 A 16 A 18 A 20 A22 A 24 A 26 A 28 and A 30 .

[0148] Face number A4 A6 A8 A10 A12 A14 A16 S1 2.3925E-01 -3.0341E-02 1.0508E-02 -9.3619E-03 4.7180E-03 -2.5854E-03 1.3939E-03 S2 -6.2713E-02 -4.7773E-03 9.8176E-03 -7.6430E-05 3.4011E-05 -8.8019E-04 -8.0796E-04 S3 -1.5696E-01 -1.4540E-02 1.6377E-03 5.6495E-04 4.4693E-05 4.2016E-05 1.0114E-05 S4 1.1159E-01 -2.1558E-02 -7.8387E-03 2.3163E-03 -6.3333E-05 -1.8856E-05 1.1083E-04 S5 1.3015E-01 -9.7744E-03 -2.6351E-04 3.7731E-06 2.8527E-06 -1.2254E-05 2.3066E-07 S6 -1.0108E-01 -1.9632E-02 -2.2212E-03 -2.6667E-03 -6.2523E-04 -3.5165E-04 -1.0095E-04 S7 4.8615E-02 1.0679E-02 -1.0349E-03 1.4331E-03 -3.3945E-04 -1.3784E-04 2.2486E-05 S8 -3.6006E-01 4.8193E-02 -8.5681E-03 2.4700E-03 -7.0537E-04 2.9672E-04 -1.0696E-04 S9 7.0571E-02 -1.9217E-03 6.8511E-03 2.2279E-03 4.0246E-04 2.5455E-04 1.4669E-04 S10 2.2620E-01 -3.0144E-02 2.9188E-03 2.0050E-03 9.5867E-05 2.0352E-04 1.3362E-04 S11 4.6341E-01 5.2259E-02 -9.2144E-03 1.1576E-02 -3.4506E-04 1.6999E-03 6.0554E-05 S12 1.9589E-01 5.5036E-02 -3.3118E-02 1.0228E-02 -2.8280E-03 1.2310E-03 -5.9458E-04 S13 1.7299E+00 1.6836E-01 -1.4958E-01 3.2062E-01 -7.0347E-02 2.1592E-02 6.7231E-03 S14 2.1802E+00 -8.8978E-01 1.4921E-01 2.0247E-01 -1.2918E-01 1.7143E-01 -1.8279E-01 Face number A18 A20 A22 A24 A26 A28 A30 S1 -7.4506E-04 3.8756E-04 -1.9464E-04 8.5082E-05 -3.4622E-05 9.0263E-06 0.0000E+00 S2 -5.3606E-04 -4.1630E-04 -2.1980E-04 -1.2661E-04 -6.1702E-05 -2.5025E-05 -5.6686E-06 S3 -3.8878E-06 -8.4643E-06 -9.3452E-07 8.7285E-07 3.1778E-06 0.0000E+00 0.0000E+00 S4 -1.1108E-04 3.1789E-05 2.3304E-05 -3.9317E-05 2.9813E-05 -6.3747E-06 4.2884E-06 S5 -1.2048E-06 1.4820E-06 -1.3435E-06 1.7442E-06 -4.7361E-08 0.0000E+00 0.0000E+00 S6 -5.4037E-05 -4.5538E-05 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 S7 4.5378E-05 -1.4149E-04 1.2619E-04 -1.1108E-04 6.7607E-05 -4.2998E-05 7.2339E-06 S8 2.7050E-05 -1.6078E-05 4.7564E-06 1.0440E-07 3.3627E-06 1.7146E-06 3.0105E-06 S9 5.3796E-05 1.1045E-05 1.3853E-05 1.0969E-06 3.5075E-06 -1.7914E-06 0.0000E+00 S10 6.7246E-05 2.3390E-06 3.9576E-06 8.2371E-06 7.7347E-07 3.2049E-06 -4.1787E-07 S11 3.0063E-04 1.8317E-06 4.8889E-05 7.5510E-06 1.1324E-05 1.0435E-06 2.4671E-06 S12 2.2085E-04 -9.0385E-05 3.8376E-05 -1.2851E-05 3.2132E-06 -1.1838E-06 -5.4459E-07 S13 -2.1207E-02 1.3877E-02 1.2370E-03 -2.5841E-03 1.6720E-03 1.1305E-03 -1.0961E-03 S14 9.1874E-02 -6.2862E-02 4.2861E-02 -2.2312E-02 1.2287E-02 -3.5850E-03 -2.6646E-05

[0149] Table 7

[0150] Example 8

[0151] The following is for reference Figure 11 An optical imaging system according to Embodiment 8 of this application is described.

[0152] like Figure 11 As shown, the optical imaging system includes a lens barrel P0 and an optical lens group and a spacer group disposed within the lens barrel P0. The structure of the optical lens group is the same as that of the optical lens group in Embodiment 7. The spacer group includes a first spacer P1, a second spacer P2, a third spacer P3, a fourth spacer P4, a fifth spacer P5, a sixth spacer P6, and a sixth auxiliary spacer P6b.

[0153] The structure of the optical lens group in this embodiment is the same as that of the optical lens group in Embodiment 7. That is, the basic parameter table of the optical imaging system in this embodiment is the same as that in Table 6, and the aspherical coefficient table is the same as that in Table 7. The difference between this embodiment and Embodiment 7 is that the structural dimensions of at least some of the components in the lens barrel P0 and the spacer assembly are different.

[0154] Example 9

[0155] The following is for reference Figure 12 An optical imaging system according to Embodiment 9 of this application is described.

[0156] like Figure 12 As shown, the optical imaging system includes a lens barrel P0 and an optical lens assembly and a spacer assembly disposed within the lens barrel P0. The structure of the optical lens assembly is the same as that of the optical lens assembly in Embodiment 7. The spacer assembly includes a first spacer P1, a second spacer P2, a second auxiliary spacer P2b, a fourth spacer P4, a fifth spacer P5, a sixth spacer P6, and a sixth auxiliary spacer P6b.

[0157] The structure of the optical lens group in this embodiment is the same as that of the optical lens group in Embodiment 7. That is, the basic parameter table of the optical imaging system in this embodiment is the same as that in Table 6, and the aspherical coefficient table is the same as that in Table 7. The difference between this embodiment and Embodiment 7 is that the structural dimensions of at least some of the components in the lens barrel P0 and the spacer assembly are different.

[0158] Figure 13AThe on-axis chromatic aberration curves of the optical imaging systems of Embodiments 7, 8, or 9 are shown, representing the deflection of the focal point after light of different wavelengths passes through the optical imaging system. Figure 13B Astigmatism curves of the optical imaging systems of Embodiments 7, 8, or 9 are shown, representing the meridional and sagittal image plane curvatures corresponding to different image heights. Figure 13C Distortion curves for the optical imaging systems of Embodiments 7, 8, or 9 are shown, representing the magnitude of distortion at different image heights. According to... Figures 13A to 13C It can be seen that the optical imaging systems of Examples 7, 8 or 9 can achieve good imaging quality.

[0159] Table 8 shows the values ​​of parameters d1s, d1m, D1m, d2s, d2m, d2bm, D2bm, d3s, d4s, D4m, D5s, D5m, d6s, d6m, D6m, d6bm, dsmin, d0s, d0m, CP2, CP4, and CP6 for each embodiment in Examples 1-9. At least some of these parameters can be calculated according to... Figure 1 The measurements were obtained using the annotation method shown, and the units for all parameters listed in Table 8 are mm.

[0160]

[0161]

[0162] Table 8

[0163] Table 9 shows the values ​​of the conditional expressions for each of the embodiments in Examples 1-9.

[0164] Conditional / Example 1 2 3 4 5 6 7 8 9 f / (d0s-d1s) 0.37 0.40 0.39 0.37 0.35 0.35 0.37 0.39 0.46 (D1m-d1m) / EPD 4.12 3.75 4.16 3.95 3.80 3.96 4.07 4.12 3.95 d2s / f1+d2m / f2 -0.73 -1.98 -0.73 -2.01 -2.01 -1.99 -2.00 -0.79 -2.03 (D2bm-d2bm) / DT31 / 2.35 / 2.27 2.17 2.28 2.22 / 2.15 d3s / CT3×N3 5.24 5.19 5.26 5.23 5.41 5.25 5.20 5.23 / (d2m-d3s) / f3 -0.12 1.31 -0.12 0.99 1.26 1.27 1.26 -0.09 / CP4 / T45 0.60 0.03 0.72 0.62 0.67 0.03 / 0.62 0.04 (D4m-d4s) / (f4+f5) -0.07 -0.24 -0.07 -0.05 -0.06 -0.16 / -0.07 -0.20 D5s / DT52 2.28 2.97 2.50 3.08 2.43 3.10 3.15 3.18 3.08 D5m / DT61 2.29 2.99 2.52 3.10 2.44 3.11 3.16 3.20 3.10 (D6m-d6s) / CP6 1.92 1.97 1.97 2.22 1.75 2.02 2.72 2.83 2.30 f6 / f7 -0.74 -0.74 -0.74 -0.73 -0.73 -0.73 -0.69 -0.69 -0.69 d6bm / T67 5.53 5.44 5.75 5.17 5.31 5.40 5.20 5.20 5.20 R13 / R14 -0.03 -0.03 -0.03 -0.04 -0.04 -0.04 0.00 0.00 0.00 (d0m-d6m) / f7 0.71 0.63 0.72 0.72 0.66 0.69 0.69 0.64 0.65 d0s / dsmin 3.65 3.61 3.54 3.50 3.61 3.67 3.41 3.27 2.94

[0165] Table 9

[0166] 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.

[0167] 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 optical lens group, along the optical axis from the object side to the image side, includes the following in sequence: The first lens with negative optical power has a concave image-side surface. A second lens with positive optical power has a convex object-side surface and a concave image-side surface; A third lens with positive optical power has a convex object-side surface and a convex image-side surface; The fourth lens with negative optical power has a convex object side and a concave image side. The fifth lens with positive optical power has a convex object-side surface and a convex image-side surface; The sixth lens with negative optical power has a concave object side and a convex image side. The seventh lens with positive optical power has a convex object-side surface and a convex image-side surface. A spacer assembly includes a first spacer, a sixth spacer, and a sixth auxiliary spacer. The first spacer is positioned on and in contact with the image-side surface of the first lens. The sixth spacer is positioned on and in contact with the image-side surface of the sixth lens. The sixth auxiliary spacer is positioned on and in contact with the image-side surface of the sixth spacer. The lens barrel, in which the optical lens group and the spacer group are placed; The optical imaging system has seven lenses with optical power. The maximum field of view (Semi-FOV) of the optical imaging system is half of the following: 68.28°≤Semi-FOV≤68.70°; The aperture number Fno of the optical imaging system satisfies: 1.71 ≤ Fno < 1.8; The total effective focal length f of the optical imaging system, the inner diameter d0s of the object-side end face of the lens barrel, and the inner diameter d1s of the object-side side face of the first spacer satisfy: 0.35≤f / (d0s-d1s)<0.5; The effective focal length f6 of the sixth lens and the effective focal length f7 of the seventh lens satisfy: -0.74≤f6 / f7≤-0.69; the air gap T67 between the sixth lens and the seventh lens on the optical axis and the inner diameter d6bm of the image side of the sixth auxiliary spacer satisfy: 5.17≤d6bm / T67≤5.

75.

2. The optical imaging system according to claim 1, characterized in that, The entrance pupil diameter EPD of the optical imaging system, the inner diameter d1m of the image side of the first spacer, and the outer diameter D1m of the image side of the first spacer satisfy: 3.75≤(D1m-d1m) / EPD≤4.

16.

3. The optical imaging system according to claim 1, characterized in that, The spacer assembly further includes a second spacer disposed on the image-side surface of the second lens and in contact with the image-side surface of the second lens; Wherein, the effective focal length f1 of the first lens, the effective focal length f2 of the second lens, the inner diameter d2s of the object side of the second spacer and the inner diameter d2m of the image side of the second spacer satisfy: -2.03≤d2s / f1+d2m / f2≤-0.

73.

4. The optical imaging system according to claim 1, characterized in that, The spacer assembly further includes a second spacer disposed on the image-side surface of the second lens and in contact with the image-side surface of the second lens, and a second auxiliary spacer disposed on the image-side surface of the second spacer and in contact with the image-side surface of the second spacer. Wherein, the maximum thickness CP2 of the second spacer is greater than 0.3mm; the effective full aperture DT31 of the light-transmitting part of the object side of the third lens, the inner diameter d2bm of the image side of the second auxiliary spacer and the outer diameter D2bm of the image side of the second auxiliary spacer satisfy: 2.15≤(D2bm-d2bm) / DT31≤2.

35.

5. The optical imaging system according to claim 1, characterized in that, The spacer assembly further includes a third spacer disposed on the image-side surface of the third lens and in contact with the image-side surface of the third lens; The central thickness CT3 of the third lens on the optical axis, the refractive index N3 of the third lens, and the inner diameter d3s of the object side of the third spacer satisfy the following: 5.19≤d3s / CT3×N3≤5.

41.

6. The optical imaging system according to claim 1, characterized in that, The spacer assembly further includes a second spacer disposed on the image-side surface of the second lens and in contact with the image-side surface of the second lens, and a third spacer disposed on the image-side surface of the third lens and in contact with the image-side surface of the third lens. Wherein, the effective focal length f3 of the third lens, the inner diameter d2m of the image side of the second spacer, and the inner diameter d3s of the object side of the third spacer satisfy: -0.12≤(d2m-d3s) / f3≤1.

31.

7. The optical imaging system according to any one of claims 1-6, characterized in that, The spacer assembly further includes a fourth spacer disposed on and in contact with the image side surface of the fourth lens; Wherein, the air gap T45 between the fourth lens and the fifth lens on the optical axis and the maximum thickness CP4 of the fourth spacer satisfy: 0 < CP4 / T45 ≤ 0.

72.

8. The optical imaging system according to any one of claims 1-6, characterized in that, The spacer assembly further includes a fourth spacer disposed on and in contact with the image side surface of the fourth lens; Wherein, the effective focal length f4 of the fourth lens, the effective focal length f5 of the fifth lens, the inner diameter d4s of the object side of the fourth spacer and the outer diameter D4m of the image side of the fourth spacer satisfy: -0.24≤(D4m-d4s) / (f4+f5)≤-0.

05.

9. The optical imaging system according to any one of claims 1-6, characterized in that, The spacer assembly further includes a fifth spacer disposed on the image-side surface of the fifth lens and in contact with the image-side surface of the fifth lens; Wherein, the effective full aperture DT52 of the light-transmitting portion of the image side of the fifth lens and the outer diameter D5s of the object side of the fifth spacer satisfy: 2.28≤D5s / DT52<3.2; the effective full aperture DT61 of the light-transmitting portion of the object side of the sixth lens and the outer diameter D5m of the image side of the fifth spacer satisfy: 2.29≤D5m / DT61≤3.

20.

10. The optical imaging system according to any one of claims 1-6, characterized in that, The inner diameter d6s of the object side of the sixth spacer, the outer diameter D6m of the image side of the sixth spacer, and the maximum thickness CP6 of the sixth spacer satisfy the following condition: 1.75≤(D6m-d6s) / CP6≤2.

83.

11. The optical imaging system according to any one of claims 1-6, characterized in that, The radius of curvature R13 of the object side of the seventh lens and the radius of curvature R14 of the image side of the seventh lens satisfy: -0.04≤R13 / R14≤0; the effective focal length f7 of the seventh lens, the inner diameter d0m of the image side end face of the lens barrel and the inner diameter d6m of the image side face of the sixth spacer satisfy: 0.63≤(d0m-d6m) / f7≤0.

72.

12. The optical imaging system according to any one of claims 1-6, characterized in that, The inner diameter d0s of the object-side end face of the lens barrel and the inner diameter dsmin of the object-side end face of the spacer with the smallest object-side inner diameter in the spacer group satisfy the following condition: 2.94≤d0s / dsmin≤3.67.

Images