An optical imaging lens

Abstract

The present invention discloses an optical imaging lens, which includes, in order from the object side to the image side along the optical axis: an aperture; a first lens with optical power; a second lens with negative optical power; a third lens with optical power; a fourth lens with positive optical power, whose object side surface is concave and whose image side surface is convex; a fifth lens with negative optical power, whose object side surface is concave and whose image side surface is concave; a sixth lens with optical power; a seventh lens with optical power; and an eighth lens with optical power. By reasonably allocating the optical power of each position of the optical imaging system, the size of the optical imaging lens can be effectively compressed, so that the light deflection angle is small, and the optical system design of large image surface ultra-thin TTL is realized.

Description

Technical Field

[0001] The present invention belongs to the field of optical imaging, and in particular relates to an optical imaging lens comprising eight lenses. Background Art

[0002] As miniaturized electronic products such as 5G smartphones have more diverse requirements for camera functions, higher requirements are placed on the hardware conditions of electrically coupled devices or complementary metal oxide semiconductor image sensors and the performance of optical imaging lenses. Mobile terminal manufacturers now have increasingly higher requirements for the specifications of rear main camera lenses. A higher chip pixel means a larger imaging surface, and a shorter optical total length TTL means a thinner phone. Systems that meet structural size requirements pose a higher difficulty in balancing aberrations such as chromatic aberration and distortion in optical imaging lenses.

[0003] Therefore, the present invention proposes an optical imaging lens which is applicable to portable electronic products and has high pixel, large image surface and good imaging quality. Summary of the invention

[0004] The present invention aims to provide an optical imaging lens composed of eight lenses, which has the characteristics of high pixel, large image surface and good imaging quality.

[0005] The present application provides an optical imaging lens, which includes, in order from the object side to the image side along the optical axis:

[0006] Aperture;

[0007] a first lens having optical power;

[0008] a second lens having negative optical power;

[0009] a third lens having optical power;

[0010] a fourth lens element having positive refractive power, whose object side surface is concave and image side surface is convex;

[0011] a fifth lens having negative optical power, whose object-side surface is concave and whose image-side surface is concave;

[0012] a sixth lens having optical power;

[0013] a seventh lens having optical power;

[0014] an eighth lens having optical power;

[0015] Among them, the on-axis distance SAG21 between the intersection of the second lens object side and the optical axis to the effective radius vertex of the second lens object side and the on-axis distance SAG31 between the intersection of the third lens object side and the optical axis to the effective radius vertex of the third lens object side satisfy: 1.0<SAG21 / SAG31<2.0.

[0016] According to one embodiment of the present application, half of the diagonal length of the effective pixel area on the imaging plane ImgH and the axial distance TTL from the object side of the first lens to the imaging plane satisfy: TTL / ImgH<1.3.

[0017] According to one embodiment of the present application, the effective focal length f of the optical imaging lens and the entrance pupil diameter EPD of the optical imaging system satisfy: f / EPD<2.5.

[0018] According to one embodiment of the present application, half of the maximum field of view Semi-FOV of the optical imaging system satisfies: Semi-FOV>40°.

[0019] According to one embodiment of the present application, a curvature radius R5 of the object-side surface of the third lens and a curvature radius R6 of the image-side surface of the third lens satisfy: 2.0<(R6+R5) / (R6-R5)<5.5.

[0020] According to one embodiment of the present application, half of the diagonal length of the effective pixel area on the imaging plane ImgH satisfies: ImgH>7.0mm.

[0021] According to one embodiment of the present application, the effective focal length f3 of the third lens and the effective focal length f7 of the seventh lens satisfy: 3.0<f3 / f7<5.5.

[0022] According to one embodiment of the present application, the on-axis distance SAG11 between the intersection of the object side surface of the first lens and the optical axis to the effective radius vertex of the object side surface of the first lens and the on-axis distance SAG22 between the intersection of the image side surface of the second lens and the optical axis to the effective radius vertex of the image side surface of the second lens satisfy: 2.0<(SAG11+SAG22) / (SAG11-SAG22)<4.0.

[0023] According to one embodiment of the present application, the on-axis distance SAG52 between the intersection of the image side surface of the fifth lens and the optical axis to the effective radius vertex of the image side surface of the fifth lens and the on-axis distance SAG61 between the intersection of the object side surface of the sixth lens and the optical axis to the effective radius vertex of the object side surface of the sixth lens satisfy: -0.5<(SAG52-SAG61) / (SAG52+SAG61)<0.

[0024] According to one embodiment of the present application, the sum of the center thicknesses of all lenses on the optical axis, ΣCT, and the center thickness CT2 of the second lens on the optical axis satisfy: 12.0<ΣCT / CT2≤14.5.

[0025] According to one embodiment of the present application, the axial distance TTL from the object side surface of the first lens to the imaging surface and the distance SD from the aperture to the image side surface of the last lens satisfy: 1.0<TTL / SD<1.5.

[0026] According to one embodiment of the present application, the Abbe number V1 of the first lens and the Abbe number V2 of the second lens satisfy: V1-V2>30.

[0027] According to one embodiment of the present application, the Abbe number V1 of the first lens and the Abbe number V4 of the fourth lens satisfy: V1-V4<20.

[0028] According to one embodiment of the present application, the effective focal length f5 of the fifth lens and the effective focal length f of the optical imaging lens satisfy: -7.5<f5 / f<-4.0.

[0029] The present application provides an optical imaging lens, which includes, in order from the object side to the image side along the optical axis:

[0030] Aperture;

[0031] a first lens having optical power;

[0032] a second lens having negative optical power;

[0033] a third lens having optical power;

[0034] a fourth lens element having positive refractive power, whose object side surface is concave and image side surface is convex;

[0035] a fifth lens having negative optical power, whose object-side surface is concave and whose image-side surface is concave;

[0036] a sixth lens having optical power;

[0037] a seventh lens having optical power;

[0038] an eighth lens having optical power;

[0039] The effective focal length f5 of the fifth lens and the effective focal length f of the optical imaging lens satisfy: -7.5<f5 / f<-4.0.

[0040] According to one embodiment of the present application, half of the diagonal length of the effective pixel area on the imaging plane ImgH and the axial distance TTL from the object side of the first lens to the imaging plane satisfy: TTL / ImgH<1.3.

[0041] According to one embodiment of the present application, the effective focal length f of the optical imaging lens and the entrance pupil diameter EPD of the optical imaging system satisfy: f / EPD<2.5.

[0042] According to one embodiment of the present application, half of the maximum field of view Semi-FOV of the optical imaging system satisfies: Semi-FOV>40°.

[0043] According to one embodiment of the present application, a curvature radius R5 of the object-side surface of the third lens and a curvature radius R6 of the image-side surface of the third lens satisfy: 2.0<(R6+R5) / (R6-R5)<5.5.

[0044] According to one embodiment of the present application, half of the diagonal length of the effective pixel area on the imaging plane ImgH satisfies: ImgH>7.0mm.

[0045] According to one embodiment of the present application, the effective focal length f3 of the third lens and the effective focal length f7 of the seventh lens satisfy: 3.0<f3 / f7<5.5.

[0046] According to one embodiment of the present application, the on-axis distance SAG11 between the intersection of the object side surface of the first lens and the optical axis to the effective radius vertex of the object side surface of the first lens and the on-axis distance SAG22 between the intersection of the image side surface of the second lens and the optical axis to the effective radius vertex of the image side surface of the second lens satisfy: 2.0<(SAG11+SAG22) / (SAG11-SAG22)<4.0.

[0047] According to one embodiment of the present application, the on-axis distance SAG52 between the intersection of the image side surface of the fifth lens and the optical axis to the effective radius vertex of the image side surface of the fifth lens and the on-axis distance SAG61 between the intersection of the object side surface of the sixth lens and the optical axis to the effective radius vertex of the object side surface of the sixth lens satisfy: -0.5<(SAG52-SAG61) / (SAG52+SAG61)<0.

[0048] According to one embodiment of the present application, the sum of the center thicknesses of all lenses on the optical axis, ΣCT, and the center thickness CT2 of the second lens on the optical axis satisfy: 12.0<ΣCT / CT2≤14.5.

[0049] According to one embodiment of the present application, the axial distance TTL from the object side surface of the first lens to the imaging surface and the distance SD from the aperture to the image side surface of the last lens satisfy: 1.0<TTL / SD<1.5.

[0050] According to one embodiment of the present application, the Abbe number V1 of the first lens and the Abbe number V2 of the second lens satisfy: V1-V2>30.

[0051] According to one embodiment of the present application, the Abbe number V1 of the first lens and the Abbe number V4 of the fourth lens satisfy: V1-V4<20.

[0052] According to one embodiment of the present application, the on-axis distance SAG21 between the intersection of the second lens object side and the optical axis to the effective radius vertex of the second lens object side and the on-axis distance SAG31 between the intersection of the third lens object side and the optical axis to the effective radius vertex of the third lens object side satisfy: 1.0<SAG21 / SAG31<2.0.

[0053] Beneficial effects of the present invention:

[0054] The optical imaging lens provided by the present invention includes multiple lenses, such as the first lens to the eighth lens. By reasonably allocating the focal length of each position of the optical imaging system, the size of the optical imaging lens can be effectively compressed, so that the light deflection angle is small, and the optical system design of large image plane ultra-thin TTL is realized; the sagittal height of the second lens and the third lens is reasonably adjusted, which can effectively reduce the risk of ghost images of the second lens and the third lens, and will help to compress the overall size of the optical imaging lens; by constraining the ratio of the effective focal length of the fifth lens to the system focal length, its contribution to the third-order spherical aberration of the system can be well controlled, thereby making the system have good imaging quality on the axis. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0056] Figure 1 Schematic diagram of the structure of a lens assembly of an optical imaging lens embodiment 1 of the present invention;

[0057] Figure 2a to Figure 2d They are respectively an axial chromatic aberration curve, an astigmatism curve, a distortion curve, and a magnification chromatic aberration curve of the optical imaging lens embodiment 1 of the present invention;

[0058] Figure 3 Schematic diagram of the lens group structure of Embodiment 2 of the optical imaging lens of the present invention;

[0059] Figures 4a to 4d They are respectively an axial chromatic aberration curve, an astigmatism curve, a distortion curve, and a magnification chromatic aberration curve of Example 2 of the optical imaging lens of the present invention;

[0060] Figure 5 Schematic diagram of the lens group structure of Embodiment 3 of the optical imaging lens of the present invention;

[0061] Figures 6a to 6d They are respectively an axial chromatic aberration curve, an astigmatism curve, a distortion curve, and a magnification chromatic aberration curve of Example 3 of the optical imaging lens of the present invention;

[0062] Figure 7 Schematic diagram of the lens group structure of Embodiment 4 of the optical imaging lens of the present invention;

[0063] Figures 8a to 8d They are respectively the axial chromatic aberration curve, the astigmatism curve, the distortion curve and the magnification chromatic aberration curve of the optical imaging lens embodiment 4 of the present invention. DETAILED DESCRIPTION

[0064] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0065] It should be noted that in this specification, the expressions of first, second, third, etc. are only used to distinguish one feature from another feature, and do not represent any limitation on the features. Therefore, without departing from the teaching of the present invention, the first lens discussed below may also be referred to as the second lens or the third lens.

[0066] It should also be understood that the terms "comprises", "including", "having", "includes" 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. In addition, when expressions such as "at least one of..." appear after a list of listed features, they modify the entire listed features rather than modifying the individual elements in the list. In addition, when describing embodiments of the present application, "may" is used to mean "one or more embodiments of the present application". And, the term "exemplary" is intended to refer to an example or illustration.

[0067] In the drawings, the thickness, size and shape of the lenses have been slightly exaggerated for ease of explanation. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are shown by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to the shapes of the spherical or aspherical surfaces shown in the drawings. The drawings are only examples and are not drawn strictly to scale.

[0068] In the description of the present invention, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the position of the convex surface 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 position of the concave surface 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 object is called the object side of the lens, and the surface of each lens closest to the imaging plane is called the image side of the lens.

[0069] Unless otherwise defined, all terms (including technical terms and scientific terms) used in this article have the same meaning as commonly understood by ordinary technicians in the field to which this application belongs. It should also be understood that terms (such as terms defined in commonly used dictionaries) should be interpreted as having the same meaning as their meaning in the context of the relevant technology, and will not be interpreted in an idealized or overly formal way unless explicitly defined in this article.

[0070] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The features, principles and other aspects of the present invention will be described in detail below with reference to the drawings and in combination with the embodiments.

[0071] Exemplary Embodiments

[0072] The optical imaging lens of an exemplary embodiment of the present invention includes eight lenses, which include, in order from the object side to the image side along the optical axis: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens and an eighth lens, wherein each lens is independent of each other and has an air gap between the lenses on the optical axis.

[0073] This exemplary embodiment provides an optical imaging lens, which includes, in order from the object side to the image side along the optical axis: an aperture; a first lens with optical power; a second lens with negative optical power; a third lens with optical power; a fourth lens with positive optical power, whose object side surface is concave and whose image side surface is convex; a fifth lens with negative optical power, whose object side surface is concave and whose image side surface is concave; a sixth lens with optical power; a seventh lens with optical power; and an eighth lens with optical power. By reasonably allocating the optical power of each position of the optical imaging system, the size of the optical imaging lens can be effectively compressed, so that the light deflection angle is small, and the optical system design of large image surface ultra-thin TTL is realized.

[0074] In this exemplary embodiment, the on-axis distance SAG21 between the intersection of the second lens object side and the optical axis to the effective radius vertex of the second lens object side and the on-axis distance SAG31 between the intersection of the third lens object side and the optical axis to the effective radius vertex of the third lens object side satisfy: 1.0<SAG21 / SAG31<2.0. Reasonable adjustment of the sagittal height of the second lens and the third lens can effectively reduce the risk of ghost images of the second and third lenses, and will help to compress the overall size of the optical imaging lens. More specifically, the on-axis distance SAG21 between the intersection of the second lens object side and the optical axis to the effective radius vertex of the second lens object side and the on-axis distance SAG31 between the intersection of the third lens object side and the optical axis to the effective radius vertex of the third lens object side satisfy: 1.30<SAG21 / SAG31<1.99.

[0075] In this exemplary embodiment, the effective focal length f5 of the fifth lens and the effective focal length f of the optical imaging lens satisfy: -7.5<f5 / f<-4.0. By constraining the ratio of the effective focal length of the fifth lens and the system focal length, its contribution to the third-order spherical aberration of the system can be well controlled, thereby making the system have good imaging quality on the axis. More specifically, the effective focal length f5 of the fifth lens and the effective focal length f of the optical imaging lens satisfy: -7.1<f5 / f<-4.3.

[0076] In this exemplary embodiment, half of the diagonal length of the effective pixel area on the imaging plane ImgH and the axial distance TTL from the object side of the first lens to the imaging plane satisfy: TTL / ImgH<1.3. Ensure that the total optical length of the entire system is limited to a certain size, so that the system has ultra-thin characteristics. More specifically, half of the diagonal length of the effective pixel area on the imaging plane ImgH and the axial distance TTL from the object side of the first lens to the imaging plane satisfy: TTL / ImgH<1.25.

[0077] In this exemplary embodiment, the effective focal length f of the optical imaging lens and the entrance pupil diameter EPD of the optical imaging system satisfy: f / EPD<2.5. This can ensure that the optical system has a larger aperture, increase the amount of light entering the system, and meet the requirements for use in a dark environment. More specifically, the effective focal length f of the optical imaging lens and the entrance pupil diameter EPD of the optical imaging system satisfy: f / EPD<2.10.

[0078] In this exemplary embodiment, the Semi-FOV of half of the maximum field of view of the optical imaging system satisfies: Semi-FOV>40°. This ensures that the optical system can obtain a wider imaging range with a field of view angle greater than 80 degrees. More specifically, the Semi-FOV of half of the maximum field of view of the optical imaging system satisfies: Semi-FOV>42.0°.

[0079] In this exemplary embodiment, the radius of curvature R5 of the object side of the third lens and the radius of curvature R6 of the image side of the third lens satisfy: 2.0<(R6+R5) / (R6-R5)<5.5. By constraining the range of the object side curvature radius and the image side curvature radius of the third lens, the coma contribution rate of the third lens is controlled within a reasonable range, thereby being able to well balance the coma generated by the system components and obtain good off-axis field of view imaging quality. More specifically, the radius of curvature R5 of the object side of the third lens and the radius of curvature R6 of the image side of the third lens satisfy: 2.0<(R6+R5) / (R6-R5)<4.5.

[0080] In this exemplary embodiment, half of the diagonal length of the effective pixel area on the imaging plane ImgH satisfies: ImgH>7.0mm. This ensures that the optical system has a large imaging range. More specifically, half of the diagonal length of the effective pixel area on the imaging plane ImgH satisfies: ImgH>7.30mm.

[0081] In this exemplary embodiment, the effective focal length f3 of the third lens and the effective focal length f7 of the seventh lens satisfy: 3.0<f3 / f7<5.5. By reasonably controlling the effective focal length ratio of the third lens to the seventh lens within a certain range, the spherical aberration generated by them can be constrained to a reasonable interval, so that it can be offset and balanced with the spherical aberration generated by the third lens and the seventh lens, so that the on-axis field of view obtains good imaging quality. More specifically, the effective focal length f3 of the third lens and the effective focal length f7 of the seventh lens satisfy: 3.20<f3 / f7<5.1.

[0082] In this exemplary embodiment, the on-axis distance SAG11 between the intersection of the object side surface of the first lens and the optical axis to the vertex of the effective radius of the object side surface of the first lens and the on-axis distance SAG22 between the intersection of the image side surface of the second lens and the optical axis to the vertex of the effective radius of the image side surface of the second lens satisfy: 2.0<(SAG11+SAG22) / (SAG11-SAG22)<4.0. By controlling the relationship between the sagittal height of the object side surface of the first lens and the sagittal height of the image side surface of the second lens within a certain range, the deflection angle of the light at the edge of the system can be reasonably controlled, and the sensitivity of the system and the optical sensitivity of the first lens and the second lens can be effectively reduced. More specifically, the on-axis distance SAG11 between the intersection of the object side surface of the first lens and the optical axis to the vertex of the effective radius of the object side surface of the first lens and the on-axis distance SAG22 between the intersection of the image side surface of the second lens and the optical axis to the vertex of the effective radius of the image side surface of the second lens satisfy: 2.50<(SAG11+SAG22) / (SAG11-SAG22)<3.70.

[0083] In this exemplary embodiment, the on-axis distance SAG52 between the intersection of the image side surface of the fifth lens and the optical axis to the effective radius vertex of the image side surface of the fifth lens and the on-axis distance SAG61 between the intersection of the object side surface of the sixth lens and the optical axis to the effective radius vertex of the object side surface of the sixth lens satisfy: -0.5<(SAG52-SAG61) / (SAG52+SAG61)<0. By controlling the sag height of the object side surface of the fifth lens and the sag height of the image side surface within a certain range, the deflection angle of the light at the edge of the system can be reasonably controlled, and the sensitivity of the system can be effectively reduced. More specifically, the on-axis distance SAG52 between the intersection of the image side surface of the fifth lens and the optical axis to the effective radius vertex of the image side surface of the fifth lens and the on-axis distance SAG61 between the intersection of the object side surface of the sixth lens and the optical axis to the effective radius vertex of the object side surface of the sixth lens satisfy: -0.48<(SAG52-SAG61) / (SAG52+SAG61)<-0.2.

[0084] In this exemplary embodiment, the sum of the center thicknesses of all lenses on the optical axis, ∑CT, and the center thickness CT2 of the second lens on the optical axis satisfy: 12.0<∑CT / CT2≤14.5. Reasonable adjustment of the sum of the center thicknesses of the first to seventh lenses and the center thickness ratio of the second lens can effectively reduce the ghost image risk of the second lens and will help to reduce the size of the camera lens group. More specifically, the sum of the center thicknesses of all lenses on the optical axis, ∑CT, and the center thickness CT2 of the second lens on the optical axis satisfy: 12.50<∑CT / CT2≤14.30.

[0085] In this exemplary embodiment, the axial distance TTL from the object side of the first lens to the imaging surface and the distance SD from the aperture to the image side of the last lens satisfy: 1.0<TTL / SD<1.5. By constraining the relative relationship between the total length of the optical system and the position of the aperture, the distortion of the system can be reasonably controlled so that the system has good distortion performance. More specifically, the axial distance TTL from the object side of the first lens to the imaging surface and the distance SD from the aperture to the image side of the last lens satisfy: 1.30<TTL / SD<1.45.

[0086] In this exemplary embodiment, the Abbe number V1 of the first lens and the Abbe number V2 of the second lens satisfy: V1-V2>30. By controlling the Abbe numbers of the first lens and the second lens located at the front of the system, the vertical axis chromatic aberration, axial chromatic aberration and spherical aberration of the system can be strongly corrected. Thus, the image quality of the system is better guaranteed. More specifically, the Abbe number V1 of the first lens and the Abbe number V2 of the second lens satisfy: V1-V2>35.

[0087] In this exemplary embodiment, the Abbe number V1 of the first lens and the Abbe number V4 of the fourth lens satisfy: V1-V4<20. By selecting materials with smaller Abbe number aberrations for the first and fourth members of the system as much as possible, the magnification chromatic aberration and vertical axis chromatic aberration of the system can be effectively corrected, thereby ensuring a better image quality of the system. More specifically, the Abbe number V1 of the first lens and the Abbe number V4 of the fourth lens satisfy: V1-V4<15.

[0088] In this exemplary embodiment, the object side surface and the image side surface of any lens of the first lens E1 to the eighth lens E8 are both aspherical surfaces, and the surface shape x of each aspherical lens can be defined by, but not limited to, the following aspherical surface formula:

[0089]

[0090] Wherein, x is the distance vector height from the vertex of the aspheric surface when the aspheric surface is at a height of h along the optical axis; c is the paraxial curvature of the aspheric surface, c=1 / R (i.e., the paraxial curvature c is the reciprocal of the curvature radius R in Table 1); k is the cone coefficient; Ai is the correction coefficient of the i-th order aspheric surface.

[0091] In this exemplary embodiment, the optical imaging lens may further include a stop. The stop may be disposed at an appropriate position as required, for example, the stop may be disposed between the object side and the first lens. Optionally, the optical imaging lens may further include a filter for correcting color deviation and / or a protective glass for protecting a photosensitive element located on the imaging surface.

[0092] The optical imaging lens according to the above embodiment of the present invention may use multiple lenses, such as the above eight lenses. By reasonably allocating the focal length, surface shape, center thickness of each lens, and axial spacing between lenses, the optical imaging lens has a larger imaging surface, a wide imaging range, and high imaging quality, and ensures the ultra-thinness of the mobile phone.

[0093] In an exemplary embodiment, at least one of the mirror surfaces of each lens is an aspherical mirror surface, that is, at least one of the mirror surfaces from the object side of the first lens to the image side of the eighth lens is an aspherical mirror surface. The characteristics of the aspherical lens are: the curvature changes continuously from the center of the lens to the periphery of the lens. Unlike the spherical lens with a constant curvature from the center of the lens to the periphery of the lens, the aspherical lens has a better curvature radius characteristic, and has the advantages of improving distortion aberration and improving astigmatism aberration. After adopting the aspherical lens, the aberration that occurs during imaging can be eliminated as much as possible, thereby improving the imaging quality. Optionally, at least one of the object side and image side of each lens in the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens is an aspherical mirror surface. Optionally, the object side and image side of each lens in the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens are all aspherical mirror surfaces.

[0094] However, those skilled in the art should understand that, without departing from the technical solution claimed in the present application, the number of lenses constituting the optical imaging lens can be changed to obtain the various results and advantages described in this specification. For example, although eight lenses are used as an example in the embodiments, the optical imaging lens is not limited to including eight lenses, and the optical imaging lens may also include other numbers of lenses if necessary.

[0095] Specific embodiments of the optical imaging lens applicable to the above embodiments are further described below with reference to the accompanying drawings. Specific embodiment 1

[0097] Figure 1 1 is a schematic diagram of the structure of a lens group of an optical imaging lens embodiment 1 of the present invention. The optical imaging lens includes, in order from the object side to the image side along the optical axis: an aperture STO, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, an eighth lens E8, a filter E9 and an imaging surface S19.

[0098] The first lens E1 has positive focal power, and its object side surface S1 is convex, and its image side surface S2 is concave. The second lens E2 has negative focal power, and its object side surface S3 is convex, and its image side surface S4 is concave. The third lens E3 has positive focal power, and its object side surface S5 is convex, and its image side surface S6 is concave. The fourth lens E4 has positive focal power, and its object side surface S7 is concave, and its image side surface S8 is convex. The fifth lens E5 has negative focal power, and its object side surface S9 is concave, and its image side surface S10 is concave. The sixth lens E6 has positive focal power, and its object side surface S11 is convex, and its image side surface S12 is concave. The seventh lens E7 has positive focal power, and its object side surface S13 is convex, and its image side surface S14 is concave. The eighth lens E8 has negative focal power, and its object side surface S15 is concave, and its image side surface S16 is concave. The filter E9 has an object-side surface S17 and an image-side surface S18. Light from the object passes through each of the surfaces S1 to S18 in sequence and is finally imaged on the imaging surface S19.

[0099] As shown in Table 1, it is a basic parameter table of the optical imaging lens of Example 1, wherein the units of the radius of curvature, thickness, and focal length are all millimeters (mm).

[0100]

[0101]

[0102] Table 1

[0103] As shown in Table 2, in Example 1, the total effective focal length of the optical imaging lens is f=7.96 mm, the distance TTL on the optical axis from the object side surface S1 of the first lens E1 to the imaging surface S17 of the optical imaging lens is 8.90 mm, and half of the diagonal length of the effective pixel area on the imaging surface S17 is ImgH=7.75 mm. Half of the maximum field of view of the optical imaging lens is Semi-FOV=43.7°.

[0104]

[0105] Table 2

[0106] The optical imaging lens in Example 1 satisfies:

[0107] SAG21 / SAG31=1.48; wherein, SAG21 is the on-axis distance between the intersection of the object side of the second lens and the optical axis to the vertex of the effective radius of the object side of the second lens, and SAG31 is the on-axis distance between the intersection of the object side of the third lens and the optical axis to the vertex of the effective radius of the object side of the third lens.

[0108] f5 / f=-5.74; wherein f5 is the effective focal length of the fifth lens, and f is the effective focal length of the optical imaging lens.

[0109] TTL / ImgH=1.15; wherein ImgH is half of the diagonal length of the effective pixel area on the imaging plane, and TTL is the axial distance from the object side of the first lens to the imaging plane.

[0110] f / EPD=2.02; where f is the effective focal length of the optical imaging lens, and EPD is the entrance pupil diameter of the optical imaging system.

[0111] (R6+R5) / (R6-R5)=3.42; wherein R5 is the radius of curvature of the object side of the third lens, and R6 is the radius of curvature of the image side of the third lens.

[0112] f3 / f7=3.22; wherein f3 is the effective focal length of the third lens, and f7 is the effective focal length of the seventh lens.

[0113] (SAG11+SAG22) / (SAG11-SAG22=2.88; wherein SAG11 is the on-axis distance between the intersection of the object side surface of the first lens and the optical axis to the vertex of the effective radius of the object side surface of the first lens, and SAG22 is the on-axis distance between the intersection of the image side surface of the second lens and the optical axis to the vertex of the effective radius of the image side surface of the second lens.

[0114] (SAG52-SAG61) / (SAG52+SAG61)=-0.44; wherein, SAG52 is the on-axis distance between the intersection of the image side surface of the fifth lens and the optical axis to the vertex of the effective radius of the image side surface of the fifth lens, and SAG61 is the on-axis distance between the intersection of the object side surface of the sixth lens and the optical axis to the vertex of the effective radius of the object side surface of the sixth lens.

[0115] ∑CT / CT2=13.16; wherein ∑CT is the sum of the center thicknesses of all lenses on the optical axis, and CT2 is the center thickness of the second lens on the optical axis.

[0116] V1-V2=36.9; wherein V1 is the Abbe number of the first lens, and V2 is the Abbe number of the second lens.

[0117] V1-V4=14.2; wherein V1 is the Abbe number of the first lens, and V4 is the Abbe number of the fourth lens.

[0118] In Example 1, the object side surface and the image side surface of any lens from the first lens E1 to the eighth lens E8 are aspherical surfaces. Table 3 shows the high-order coefficients A4, A6, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, A22, A23, A24, A25, A26, A27, A28, A29, A30, A31, A32, A33, A34, A35, A36, A37, A38, A39, A40, A41, A42, A43, A44, A45, A46, A47, A48, A49, A50, A51, A52, A53, A54, A55, A56, A57, A58, A5 10 , A 12 , A 14 , A 16 , A 18 , A 20 , A 22 , A24 , A 26 , A 28 and A 30 .

[0119]

[0120]

[0121] Table 3

[0122] Figure 2a The axial chromatic aberration curve of the optical imaging lens of Example 1 is shown, which indicates the deviation of light of different wavelengths from the focal point behind the lens. Figure 2b The astigmatism curve of the optical imaging lens of Example 1 is shown, which represents the meridional image curvature and the sagittal image curvature. Figure 2c The distortion curve of the optical imaging lens of Example 1 is shown, which represents the distortion magnitude values ​​corresponding to different image heights. Figure 2d The magnification chromatic aberration curve of the optical imaging lens of Example 1 is shown, which represents the deviation of different image heights on the imaging surface after the light passes through the lens. Figure 2a to Figure 2d It can be seen from the figure that the optical imaging lens provided in Example 1 can achieve good imaging quality. Specific embodiment 2

[0124] Figure 3 2 is a schematic diagram of the lens group structure of an optical imaging lens embodiment 2 of the present invention. The optical imaging lens includes, from the object side to the image side along the optical axis, an aperture STO, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, an eighth lens E8, a filter E9 and an imaging surface S19.

[0125] The first lens E1 has positive focal power, and its object side surface S1 is convex, and its image side surface S2 is concave. The second lens E2 has negative focal power, and its object side surface S3 is convex, and its image side surface S4 is concave. The third lens E3 has positive focal power, and its object side surface S5 is convex, and its image side surface S6 is concave. The fourth lens E4 has positive focal power, and its object side surface S7 is concave, and its image side surface S8 is convex. The fifth lens E5 has negative focal power, and its object side surface S9 is concave, and its image side surface S10 is concave. The sixth lens E6 has positive focal power, and its object side surface S11 is convex, and its image side surface S12 is concave. The seventh lens E7 has positive focal power, and its object side surface S13 is convex, and its image side surface S14 is concave. The eighth lens E8 has negative focal power, and its object side surface S15 is concave, and its image side surface S16 is concave. The filter E9 has an object-side surface S17 and an image-side surface S18. Light from the object passes through each of the surfaces S1 to S18 in sequence and is finally imaged on the imaging surface S19.

[0126] As shown in Table 4, it is a basic parameter table of the optical imaging lens of Example 2, wherein the units of the radius of curvature, thickness, and focal length are all millimeters (mm).

[0127]

[0128]

[0129] Table 4

[0130] As shown in Table 5, in Example 2, the total effective focal length of the optical imaging lens is f=7.93 mm, the distance TTL on the optical axis from the object side surface S1 of the first lens E1 to the imaging surface S17 of the optical imaging lens is 8.90 mm, and half of the diagonal length of the effective pixel area on the imaging surface S17 is ImgH=7.40 mm. Half of the maximum field of view of the optical imaging lens is Semi-FOV=42.4°.

[0131]

[0132] Table 5

[0133] The optical imaging lens in Example 2 satisfies:

[0134] SAG21 / SAG31=1.98; wherein, SAG21 is the on-axis distance between the intersection of the object side of the second lens and the optical axis to the vertex of the effective radius of the object side of the second lens, and SAG31 is the on-axis distance between the intersection of the object side of the third lens and the optical axis to the vertex of the effective radius of the object side of the third lens.

[0135] f5 / f=-7.07; wherein f5 is the effective focal length of the fifth lens, and f is the effective focal length of the optical imaging lens.

[0136] TTL / ImgH=1.20; wherein ImgH is half of the diagonal length of the effective pixel area on the imaging plane, and TTL is the axial distance from the object side of the first lens to the imaging plane.

[0137] f / EPD=2.02; where f is the effective focal length of the optical imaging lens, and EPD is the entrance pupil diameter of the optical imaging system.

[0138] (R6+R5) / (R6-R5)=4.33; wherein R5 is the radius of curvature of the object side of the third lens, and R6 is the radius of curvature of the image side of the third lens.

[0139] f3 / f7=5.07; wherein f3 is the effective focal length of the third lens, and f7 is the effective focal length of the seventh lens.

[0140] (SAG11+SAG22) / (SAG11-SAG22=2.57; wherein SAG11 is the on-axis distance between the intersection of the object side surface of the first lens and the optical axis to the vertex of the effective radius of the object side surface of the first lens, and SAG22 is the on-axis distance between the intersection of the image side surface of the second lens and the optical axis to the vertex of the effective radius of the image side surface of the second lens.

[0141] (SAG52-SAG61) / (SAG52+SAG61)=-0.46; wherein, SAG52 is the on-axis distance between the intersection of the image side surface of the fifth lens and the optical axis to the vertex of the effective radius of the image side surface of the fifth lens, and SAG61 is the on-axis distance between the intersection of the object side surface of the sixth lens and the optical axis to the vertex of the effective radius of the object side surface of the sixth lens.

[0142] ∑CT / CT2=12.54; wherein ∑CT is the sum of the center thicknesses of all lenses on the optical axis, and CT2 is the center thickness of the second lens on the optical axis.

[0143] V1-V2=36.9; wherein V1 is the Abbe number of the first lens, and V2 is the Abbe number of the second lens.

[0144] V1-V4=14.2; wherein V1 is the Abbe number of the first lens, and V4 is the Abbe number of the fourth lens.

[0145] In Example 2, the object side surface and the image side surface of any one of the first lens E1 to the eighth lens E8 are aspherical surfaces. Table 6 shows the high-order coefficients A4, A6, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, A22, A23, A24, A25, A26, A27, A28, A29, A30, A31, A32, A33, A34, A35, A36, A37, A38, A39, A40, A41, A42, A43, A44, A45, A46, A47, A48, A49, A50, A51, A52, A53, A54, A55, A56, A57, A58, A5 10 , A 12 , A 14 , A 16 , A 18 , A 20 , A 22 , A 24 , A 26 , A 28 and A 30 .

[0146]

[0147]

[0148] Table 6

[0149] Figure 4a The axial chromatic aberration curve of the optical imaging lens of Example 2 is shown, which indicates that light of different wavelengths deviates from the focal point behind the lens. Figure 4b The astigmatism curve of the optical imaging lens of Example 2 is shown, which represents the meridional image curvature and the sagittal image curvature. Figure 4cThe distortion curve of the optical imaging lens of Example 2 is shown, which represents the distortion magnitude values ​​corresponding to different image heights. Figure 4d The magnification chromatic aberration curve of the optical imaging lens of Example 2 is shown, which represents the deviation of different image heights on the imaging surface after the light passes through the lens. Figures 4a to 4d It can be seen from the figure that the optical imaging lens provided in Example 2 can achieve good imaging quality. Specific embodiment 3

[0151] Figure 5 2 is a schematic diagram of the lens group structure of Embodiment 3 of the optical imaging lens of the present invention. The optical imaging lens comprises, in order from the object side to the image side along the optical axis, an aperture STO, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, an eighth lens E8, a filter E9 and an imaging surface S19.

[0152] The first lens E1 has positive focal power, and its object side surface S1 is convex, and its image side surface S2 is concave. The second lens E2 has negative focal power, and its object side surface S3 is convex, and its image side surface S4 is concave. The third lens E3 has positive focal power, and its object side surface S5 is convex, and its image side surface S6 is concave. The fourth lens E4 has positive focal power, and its object side surface S7 is concave, and its image side surface S8 is convex. The fifth lens E5 has negative focal power, and its object side surface S9 is concave, and its image side surface S10 is concave. The sixth lens E6 has positive focal power, and its object side surface S11 is convex, and its image side surface S12 is convex. The seventh lens E7 has positive focal power, and its object side surface S13 is convex, and its image side surface S14 is concave. The eighth lens E8 has negative focal power, and its object side surface S15 is concave, and its image side surface S16 is concave. The filter E9 has an object-side surface S17 and an image-side surface S18. Light from the object passes through each of the surfaces S1 to S18 in sequence and is finally imaged on the imaging surface S19.

[0153] As shown in Table 7, it is a basic parameter table of the optical imaging lens of Example 3, wherein the units of the radius of curvature, thickness, and focal length are all millimeters (mm).

[0154]

[0155]

[0156] Table 7

[0157] As shown in Table 8, in Example 3, the total effective focal length of the optical imaging lens is f=8.01 mm, the distance TTL on the optical axis from the object side surface S1 of the first lens E1 to the imaging surface S17 of the optical imaging lens is 9.51 mm, and half of the diagonal length of the effective pixel area on the imaging surface S17 is ImgH=8.29 mm. Half of the maximum field of view of the optical imaging lens is Semi-FOV=45.4°.

[0158]

[0159] Table 8

[0160] The optical imaging lens in Example 3 satisfies:

[0161] SAG21 / SAG31=1.87; wherein, SAG21 is the on-axis distance between the intersection of the object side of the second lens and the optical axis to the vertex of the effective radius of the object side of the second lens, and SAG31 is the on-axis distance between the intersection of the object side of the third lens and the optical axis to the vertex of the effective radius of the object side of the third lens.

[0162] f5 / f=--4.40; wherein f5 is the effective focal length of the fifth lens, and f is the effective focal length of the optical imaging lens.

[0163] TTL / ImgH=1.15; wherein ImgH is half of the diagonal length of the effective pixel area on the imaging plane, and TTL is the axial distance from the object side of the first lens to the imaging plane.

[0164] f / EPD=1.88; where f is the effective focal length of the optical imaging lens, and EPD is the entrance pupil diameter of the optical imaging system.

[0165] (R6+R5) / (R6-R5)=2.04; wherein R5 is the radius of curvature of the object side of the third lens, and R6 is the radius of curvature of the image side of the third lens.

[0166] f3 / f7=4.15; wherein f3 is the effective focal length of the third lens, and f7 is the effective focal length of the seventh lens.

[0167] (SAG11+SAG22) / (SAG11-SAG22=3.60; wherein SAG11 is the on-axis distance between the intersection of the object side surface of the first lens and the optical axis to the vertex of the effective radius of the object side surface of the first lens, and SAG22 is the on-axis distance between the intersection of the image side surface of the second lens and the optical axis to the vertex of the effective radius of the image side surface of the second lens.

[0168] (SAG52-SAG61) / (SAG52+SAG61)=-0.29; wherein, SAG52 is the on-axis distance between the intersection of the image side surface of the fifth lens and the optical axis to the vertex of the effective radius of the image side surface of the fifth lens, and SAG61 is the on-axis distance between the intersection of the object side surface of the sixth lens and the optical axis to the vertex of the effective radius of the object side surface of the sixth lens.

[0169] ∑CT / CT2=14.26; wherein ∑CT is the sum of the center thicknesses of all lenses on the optical axis, and CT2 is the center thickness of the second lens on the optical axis.

[0170] V1-V2=36.9; wherein V1 is the Abbe number of the first lens, and V2 is the Abbe number of the second lens.

[0171] V1-V4=14.2; wherein V1 is the Abbe number of the first lens, and V4 is the Abbe number of the fourth lens.

[0172] In Example 3, the object side surface and the image side surface of any one of the first lens E1 to the eighth lens E8 are aspherical surfaces. Table 9 shows the high-order coefficients A4, A6, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, A22, A23, A24, A25, A26, A27, A28, A29, A30, A31, A32, A33, A34, A35, A36, A37, A38, A39, A40, A41, A42, A43, A44, A45, A46, A47, A48, A49, A50, A51, A52, A53, A54, A55, A56, A57, A58, A5 10 , A 12 , A 14 , A 16 , A 18 , A 20 , A 22 , A 24 , A 26 , A 28 and A 30 .

[0173]

[0174]

[0175] Table 9

[0176] Figure 6a The axial chromatic aberration curve of the optical imaging lens of Example 3 is shown, which indicates that light of different wavelengths deviates from the focal point behind the lens. Figure 6b The astigmatism curve of the optical imaging lens of Example 3 is shown, which represents the meridional image curvature and the sagittal image curvature. Figure 6c The distortion curve of the optical imaging lens of Example 3 is shown, which represents the distortion magnitude values ​​corresponding to different image heights. Figure 6d The magnification chromatic aberration curve of the optical imaging lens of Example 3 is shown, which represents the deviation of different image heights on the imaging surface after the light passes through the lens. Figures 6a to 6d It can be seen from the figure that the optical imaging lens provided in Example 3 can achieve good imaging quality. Specific embodiment 4

[0178] Figure 7 2 is a schematic diagram of the lens group structure of an optical imaging lens embodiment 4 of the present invention. The optical imaging lens includes, in order from the object side to the image side along the optical axis: an aperture STO, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7, an eighth lens E8, a filter E9 and an imaging surface S19.

[0179] The first lens E1 has positive focal power, and its object side surface S1 is convex, and its image side surface S2 is concave. The second lens E2 has negative focal power, and its object side surface S3 is convex, and its image side surface S4 is concave. The third lens E3 has positive focal power, and its object side surface S5 is convex, and its image side surface S6 is concave. The fourth lens E4 has positive focal power, and its object side surface S7 is concave, and its image side surface S8 is convex. The fifth lens E5 has negative focal power, and its object side surface S9 is concave, and its image side surface S10 is concave. The sixth lens E6 has positive focal power, and its object side surface S11 is convex, and its image side surface S12 is convex. The seventh lens E7 has positive focal power, and its object side surface S13 is convex, and its image side surface S14 is concave. The eighth lens E8 has negative focal power, and its object side surface S15 is concave, and its image side surface S16 is concave. The filter E9 has an object-side surface S17 and an image-side surface S18. Light from the object passes through each of the surfaces S1 to S18 in sequence and is finally imaged on the imaging surface S19.

[0180] As shown in Table 10, it is a basic parameter table of the optical imaging lens of Example 4, wherein the units of the curvature radius, thickness, and focal length are all millimeters (mm).

[0181]

[0182]

[0183] Table 10

[0184] As shown in Table 11, in Example 4, the total effective focal length of the optical imaging lens is f=8.39 mm, the distance TTL on the optical axis from the object-side surface S1 of the first lens E1 to the imaging surface S17 of the optical imaging lens is 9.52 mm, and half of the diagonal length of the effective pixel area on the imaging surface S17 is ImgH=8.00 mm. Half of the maximum field of view of the optical imaging lens is Semi-FOV=43.0°.

[0185]

[0186] Table 11

[0187] The optical imaging lens in Example 4 satisfies:

[0188] SAG21 / SAG31=1.37; wherein, SAG21 is the on-axis distance between the intersection of the object side of the second lens and the optical axis to the vertex of the effective radius of the object side of the second lens, and SAG31 is the on-axis distance between the intersection of the object side of the third lens and the optical axis to the vertex of the effective radius of the object side of the third lens.

[0189] f5 / f=--5.78; wherein f5 is the effective focal length of the fifth lens, and f is the effective focal length of the optical imaging lens.

[0190] TTL / ImgH=1.19; wherein ImgH is half of the diagonal length of the effective pixel area on the imaging plane, and TTL is the axial distance from the object side of the first lens to the imaging plane.

[0191] f / EPD=1.95; where f is the effective focal length of the optical imaging lens, and EPD is the entrance pupil diameter of the optical imaging system.

[0192] (R6+R5) / (R6-R5)=3.67; wherein R5 is the radius of curvature of the object side of the third lens, and R6 is the radius of curvature of the image side of the third lens.

[0193] f3 / f7=3.56; wherein f3 is the effective focal length of the third lens, and f7 is the effective focal length of the seventh lens.

[0194] (SAG11+SAG22) / (SAG11-SAG22=2.67; wherein SAG11 is the on-axis distance between the intersection of the object side surface of the first lens and the optical axis to the vertex of the effective radius of the object side surface of the first lens, and SAG22 is the on-axis distance between the intersection of the image side surface of the second lens and the optical axis to the vertex of the effective radius of the image side surface of the second lens.

[0195] (SAG52-SAG61) / (SAG52+SAG61)=-0.46; wherein, SAG52 is the on-axis distance between the intersection of the image side surface of the fifth lens and the optical axis to the vertex of the effective radius of the image side surface of the fifth lens, and SAG61 is the on-axis distance between the intersection of the object side surface of the sixth lens and the optical axis to the vertex of the effective radius of the object side surface of the sixth lens.

[0196] ∑CT / CT2=14.02; wherein ∑CT is the sum of the center thicknesses of all lenses on the optical axis, and CT2 is the center thickness of the second lens on the optical axis.

[0197] V1-V2=36.9; wherein V1 is the Abbe number of the first lens, and V2 is the Abbe number of the second lens.

[0198] V1-V4=14.2; wherein V1 is the Abbe number of the first lens, and V4 is the Abbe number of the fourth lens.

[0199] In Example 4, the object side surface and the image side surface of any one of the first lens E1 to the eighth lens E8 are aspherical surfaces. Table 12 shows the high-order coefficients A4, A6, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, A22, A23, A24, A25, A26, A27, A28, A29, A30, A31, A32, A33, A34, A35, A36, A37, A38, A39, A40, A41, A42, A43, A44, A45, A46, A47, A48, A49, A50, A51, A52, A53, A54, A55, A56, A57, A58, A 10 , A 12 , A 14 , A 16 , A 18 , A 20 , A 22 , A 24 , A 26 , A 28 and A 30 .

[0200]

[0201]

[0202] Table 12

[0203] Figure 8a The axial chromatic aberration curve of the optical imaging lens of Example 4 is shown, which indicates the deviation of light of different wavelengths from the focal point behind the lens. Figure 8b The astigmatism curve of the optical imaging lens of Example 4 is shown, which represents the meridional image curvature and the sagittal image curvature. Figure 8c The distortion curve of the optical imaging lens of Example 4 is shown, which represents the distortion magnitude values ​​corresponding to different image heights. Figure 8d The magnification chromatic aberration curve of the optical imaging lens of Example 4 is shown, which represents the deviation of different image heights on the imaging surface after the light passes through the lens. Figures 8a to 8d It can be seen from the figure that the optical imaging lens provided in Example 4 can achieve good imaging quality.

[0204] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, improvements, equivalent substitutions, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An optical imaging lens, characterized in that: The optical imaging lens has eight lenses with optical power, and the optical imaging lens includes, in order from the object side to the image side along the optical axis: Aperture; The first lens has positive refractive power, and its object side surface is convex and its image side surface is concave; The second lens has a negative optical power, and its object side surface is convex and its image side surface is concave; The third lens has positive power, its object side surface is convex and its image side surface is concave; a fourth lens element having positive refractive power, whose object side surface is concave and image side surface is convex; a fifth lens having negative optical power, whose object-side surface is concave and whose image-side surface is concave; a sixth lens having positive refractive power and a convex object-side surface; The seventh lens has positive refractive power, and its object side surface is convex and its image side surface is concave; An eighth lens having negative optical power, whose object side surface is concave and image side surface is concave; Wherein, the on-axis distance SAG21 between the intersection of the second lens object side surface and the optical axis to the vertex of the effective radius of the second lens object side surface and the on-axis distance SAG31 between the intersection of the third lens object side surface and the optical axis to the vertex of the effective radius of the third lens object side surface satisfies: 1.37≤SAG21 / SAG31≤1.98; The sum of the center thicknesses of all lenses on the optical axis, ∑CT, and the center thickness CT2 of the second lens on the optical axis satisfy: 12.54≤∑CT / CT2≤14.26; the axial distance SAG52 between the intersection of the image side surface of the fifth lens and the optical axis to the vertex of the effective radius of the image side surface of the fifth lens and the axial distance SAG61 between the intersection of the object side surface of the sixth lens and the optical axis to the vertex of the effective radius of the object side surface of the sixth lens satisfy: -0.46≤(SAG52-SAG61) / (SAG52+SAG61)≤-0.29; The effective focal length f5 of the fifth lens and the effective focal length f of the optical imaging lens satisfy: -7.07≤f5 / f≤-5.

74.

2. The optical imaging lens according to claim 1, wherein: Half of the diagonal length of the effective pixel area on the imaging plane ImgH and the axial distance TTL from the object side of the first lens to the imaging plane satisfy: 1.15≤TTL / ImgH≤1.

20.

3. The optical imaging lens according to claim 1, wherein: The effective focal length f of the optical imaging lens and the entrance pupil diameter EPD of the optical imaging system satisfy: 1.88≤f / EPD≤2.

02.

4. The optical imaging lens according to claim 1, wherein: Half of the maximum field of view Semi-FOV of the optical imaging system satisfies: 42.4°≤Semi-FOV≤45.4°.

5. The optical imaging lens according to claim 1, wherein: A curvature radius R5 of the object side surface of the third lens and a curvature radius R6 of the image side surface of the third lens satisfy: 2.04≤(R6+R5) / (R6-R5)≤4.

33.

6. The optical imaging lens according to claim 1, wherein: Half of the diagonal length of the effective pixel area on the imaging plane ImgH satisfies: 7.4≤ImgH≤8.

29.

7. The optical imaging lens according to claim 1, wherein: The effective focal length f3 of the third lens and the effective focal length f7 of the seventh lens satisfy: 3.22≤f3 / f7≤5.

07.

8. The optical imaging lens according to claim 1, wherein: The on-axis distance SAG11 between the intersection of the object side of the first lens and the optical axis to the effective radius vertex of the object side of the first lens and the on-axis distance SAG22 between the intersection of the image side of the second lens and the optical axis to the effective radius vertex of the image side of the second lens satisfy: 2.57≤(SAG11+SAG22) / (SAG11-SAG22)≤3.

6.

9. The optical imaging lens according to claim 1, wherein: The Abbe number V1 of the first lens and the Abbe number V2 of the second lens satisfy: V1-V2=36.

9.

10. The optical imaging lens according to claim 1, wherein: The Abbe number V1 of the first lens element and the Abbe number V4 of the fourth lens element satisfy: V1-V4=14.2.

Images