Telephoto mobile phone lens

Abstract

The present invention discloses a telephoto mobile phone lens. The telephoto mobile phone lens includes four lenses with optical power, namely a first lens, a second lens, a third lens, and a fourth lens arranged in sequence from the object side to the image side along the optical axis. Among them, the first lens has a positive optical power, and the back focal length BFL of the telephoto mobile phone lens and the aperture R8 of the mirror surface of the image side of the fourth lens satisfy: 0 < BFL / R8 < 0.2. The telephoto mobile phone lens of the present invention can not only achieve a large aperture and a large target surface, but also achieve a small aperture.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of mobile phone lenses, in particular to a long-focus mobile phone lens. BACKGROUND

[0002] With the development of smart phones, people have higher and higher requirements for the image of mobile phone lenses, and the demand for zooming is getting bigger and bigger. Long-focus mobile phone lenses can easily capture distant scenery, buildings, natural landscapes, etc., and can take clear long-distance photos through optical zoom.

[0003] However, long-focus mobile phone lenses have a long focal length, resulting in a long optical length of the lens. In order to facilitate installation in a mobile phone, a horizontal installation is usually adopted. The aperture of the mobile phone long-focus lens becomes a key factor affecting the thickness of the mobile phone body. In order to achieve a large aperture, the aperture of the mobile phone long-focus lens is usually large, resulting in an increase in the thickness of the mobile phone body. Therefore, a solution is needed that can achieve a large aperture and a large target surface while also achieving a small aperture. SUMMARY

[0004] In view of the above problems, the purpose of the present application is to provide a long-focus mobile phone lens that can achieve a large aperture and a large target surface while also achieving a small aperture.

[0005] The present application provides a long-focus mobile phone lens, which sequentially arranges a first lens, a second lens, a third lens and a fourth lens from the object side to the image side along the optical axis; wherein the first lens has a positive focal power, and the back focal length BFL of the long-focus mobile phone lens and the aperture R8 of the image side surface of the fourth lens satisfy: 0 < BFL / R8 < 0.2.

[0006] Optionally, the long-focus mobile phone lens further comprises a prism placed between the fourth lens and the imaging surface, and the back focal length BFL of the long-focus mobile phone lens and the thickness Dp of the prism satisfy: -0.2 ≤ BFL / Dp ≤ 0.

[0007] Optionally, the Abbe number V1 of the first lens, the Abbe number V2 of the second lens, the Abbe number V3 of the third lens and the Abbe number V4 of the fourth lens satisfy: 33 ≤ |V1-V2| ≤ 34, 35 ≤ |V3-V4| ≤ 36.

[0008] Optionally, the focal length f1 of the first lens, the focal length f2 of the second lens, the focal length f3 of the third lens and the focal length f4 of the fourth lens satisfy: -0.5 ≤ f1 / fi ≤ 0, i takes the value of 2, 3 or 4.

[0009] Optionally, the refractive index N1 of the first lens, the refractive index N2 of the second lens, the refractive index N3 of the third lens and the refractive index N4 of the fourth lens satisfy: Ni / N1 < 1, i takes the value of 2, 3 or 4.

[0010] Optionally, a distance TD from an object side surface of the first lens to an image side surface of the fourth lens and a distance TTLD from the object side surface of the first lens to the structure of the prism satisfy: 0.4≤TD / TTLD≤0.5.

[0011] Optionally, a focal length f1 of the first lens, a focal length f2 of the second lens, a focal length f3 of the third lens and a focal length f4 of the fourth lens satisfy: -67≤f2+f3+f4≤-63.

[0012] Optionally, a sag SR7 of a surface type of the object side surface of the fourth lens and a sag SR8 of a surface type of the image side surface of the fourth lens satisfy: -0.3≤SR7-SR8≤0.

[0013] Optionally, a surface type radius R1 of the object side surface of the first lens and a surface type radius R2 of the image side surface of the first lens satisfy: -100≤R1-R2 / R1*R2≤-20.

[0014] Optionally, a central thickness CT12 of the first lens and the surface type radius R1 of the object side surface of the first lens satisfy: 0.2≤CT12 / R1≤0.3.

[0015] Optionally, a focal length f of the long-focus mobile phone lens, an aperture Fno of the long-focus mobile phone lens and a back focal length BFL of the long-focus mobile phone lens satisfy: 0.5≤f / Fno*BFL≤4.

[0016] The long-focus mobile phone lens provided by the application has the advantages that the first lens has positive refractive power, the back focal length BFL of the long-focus mobile phone lens and the aperture R8 of the image side surface of the fourth lens satisfy: 0<BFL / R8<0.2, which can limit the size of the lens aperture, ensure the optical performance of the lens and keep the miniaturization feature of the lens, thereby thinning the thickness of the mobile phone body, so that large-aperture large-target can be realized to increase the information amount of the lens, and small-aperture can also be realized. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0018] Figure 1 An optical structure schematic diagram of a long-focus mobile phone lens according to Embodiment 1 of the application is shown;

[0019] Figures 2A to 2FThe MTF curve, relative illumination and image height diagram, field curvature diagram, distortion diagram, axial aberration diagram and transverse chromatic aberration diagram of the telephoto mobile phone lens of Example 1 are shown respectively.

[0020] Figure 3 A schematic diagram of the optical structure of a telephoto mobile phone lens according to Embodiment 2 of this application is shown;

[0021] Figures 4A to 4F The MTF curve, relative illumination and image height diagram, field curvature diagram, distortion diagram, axial aberration diagram, and transverse chromatic aberration diagram of the telephoto mobile phone lens of Example 2 are shown respectively. Detailed Implementation

[0022] The foregoing and other technical contents, features, and effects of the present invention will be clearly presented in the following detailed description of preferred embodiments with reference to the accompanying drawings. Through the description of the specific embodiments, a more in-depth and specific understanding can be gained of the technical means and effects adopted by the present invention to achieve its intended purpose. However, the accompanying drawings are for reference and illustration only and are not intended to limit the present invention; some well-known parts may not be shown. In the various drawings, the same elements are represented by similar reference numerals. For clarity, the various parts in the drawings are not necessarily drawn strictly to scale.

[0023] It is important to understand that the terms "first," "second," "third," "fourth," etc., are used merely to distinguish elements or circuits with similar properties, and do not indicate or imply relative importance or a specific order. The terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, which includes not only the listed elements but also other elements not expressly listed.

[0024] In the accompanying drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for ease of illustration. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are illustrated by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustrative purposes only and are not strictly to scale.

[0025] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the location of the convexity is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the location of the concaveness is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the subject is called the object-side surface of the lens, and the surface of each lens closest to the imaging plane is called the image-side surface of the lens.

[0026] It should be noted that, without conflict, the embodiments in this application and the features in the embodiments can be combined with each other. The following will detail this application by referring to the drawings and in conjunction with the embodiments.

[0027] The features, principles and other aspects of this application will be described in detail below.

[0028] The telephoto mobile phone lens according to an exemplary embodiment of this application includes four lenses with optical powers, namely, a first lens, a second lens, a third lens and a fourth lens arranged in sequence from the object side to the image side along the optical axis. Among them, the first lens has a positive optical power, and the back focal length BFL of the telephoto mobile phone lens and the aperture R8 of the mirror surface of the image side of the fourth lens satisfy: 0 < BFL / R8 < 0.2. By setting the first lens to have a positive optical power and reasonably distributing the optical powers of each lens, the purpose of reducing the lens aperture and shortening the system length can be achieved. Controlling the relationship between the back focal length BFL of the telephoto mobile phone lens and the aperture R8 of the mirror surface of the image side of the fourth lens can play a role in restricting the size of the lens aperture, ensuring the optical performance of the lens while maintaining the miniaturized characteristics of the lens, and further achieving the effect of thinning the thickness of the mobile phone body.

[0029] In an exemplary embodiment, the telephoto mobile phone lens according to this application further includes a prism disposed between the fourth lens and the imaging surface. The prism is used to realize the folding of the optical path and the focusing of light. The light is refracted and reflected inside the prism, causing the direction of the light to change, and focusing the light onto the imaging plane of the lens to achieve the effect of magnifying distant targets; the telephoto mobile phone lens can satisfy: -0.2 ≤ BFL / Dp ≤ 0, where BFL is the back focal length of the telephoto mobile phone lens and Dp is the thickness of the prism. Satisfying -0.2 ≤ BFL / Dp ≤ 0, by controlling the back focal length of the telephoto mobile phone lens and the thickness of the prism, it has the effect of restricting the size of the overall optical length TTL to reduce the size requirements.

[0030] In an exemplary embodiment, the telephoto mobile phone lens according to this application further includes a filter for correcting color deviation and / or a protective glass for protecting the photosensitive element located on the imaging surface.

[0031] In an exemplary embodiment, the telephoto mobile phone lens according to this application can satisfy: 33 ≤ |V1 - V2| ≤ 34, 35 ≤ |V3 - V4| ≤ 36, where V1, V2, V3, and V4 are the Abbe numbers of the first lens, the second lens, the third lens, and the fourth lens respectively. Satisfying 33 ≤ |V1 - V2| ≤ 34, 35 ≤ |V3 - V4| ≤ 36, by controlling the Abbe numbers of the first lens, the second lens, the third lens, and the fourth lens, it is beneficial for the combination of high and low dispersion coefficients, and thus can better correct chromatic aberration.

[0032] In an exemplary embodiment, the telephoto mobile phone lens according to this application satisfies: -0.5 ≤ f1 / fi ≤ 0 (i = 2, 3, 4), where f is the focal length of the telephoto mobile phone lens, and fi (i = 2, 3, 4) are the focal lengths of the second lens, the third lens, and the fourth lens. Satisfying -0.5 ≤ f1 / fi ≤ 0 (i = 2, 3, 4), by controlling the focal lengths of the second lens, the third lens, and the fourth lens, can achieve aberration correction.

[0033] In an exemplary embodiment, the telephoto mobile phone lens according to this application satisfies: .Ni / N1<1 (i=2,3,4), where Ni (i=2,3,4) are the refractive indices of the second, third, and fourth lenses, and N1 is the refractive index of the first lens. Satisfying .Ni / N1<1 (i=2,3,4), by controlling the refractive indices of the first, second, third, and fourth lenses, can facilitate the formation of a height difference in the light aperture, which is beneficial for field curvature correction.

[0034] In an exemplary embodiment, the telephoto mobile phone lens according to this application satisfies: 0.4 ≤ TD / TTLD ≤ 0.5, where TD is the distance from the object-side surface of the first lens to the image-side surface of the fourth lens, and TTLD is the structural distance from the object-side surface of the first lens to the prism. Satisfying 0.4 ≤ TD / TTLD ≤ 0.5, by controlling the distance from the object-side surface of the first lens to the image-side surface of the fourth lens, and the structural distance from the object-side surface of the first lens to the prism, allows for a more compact lens element in the imaging portion of the lens, thereby reducing the impact of stray light on image quality.

[0035] In an exemplary embodiment, the telephoto mobile phone lens according to this application satisfies: -67 ≤ f2 + f3 + f4 ≤ -63, where f2 is the focal length of the second lens, f3 is the focal length of the third lens, and f4 is the focal length of the fourth lens. By satisfying -67 ≤ f2 + f3 + f4 ≤ -63 and controlling the focal lengths of the second, third, and fourth lenses, the deflection angle of light can be controlled within a certain range, which is beneficial for correcting spherical aberration and coma.

[0036] In an exemplary embodiment, the telephoto mobile phone lens according to this application satisfies: -0.3≤SR7-SR8≤0, where SR7 and SR8 represent the sagitta of the object-side and image-side surface profiles of the fourth lens, respectively. Satisfying -0.3≤SR7-SR8≤0, by controlling the sagitta of the object-side and image-side surface profiles of the fourth lens, is beneficial for correcting field curvature. Preferably, the object-side surface profile of the fourth lens has a negative sagitta, and the image-side surface profile of the fourth lens has a positive sagitta; a combination of positive and negative sagitta is beneficial for correcting field curvature.

[0037] In an exemplary embodiment, the telephoto mobile phone lens according to this application satisfies: -100≤R1-R2 / R1*R2≤-20, where R1 and R2 represent the surface radii of the object-side and image-side surfaces of the first lens, respectively. By satisfying -100≤R1-R2 / R1*R2≤-20 and controlling the surface radii of the object-side and image-side surfaces of the first lens, the first lens has the maximum optical power and plays the main function of light convergence in the entire system, rather than aberration correction.

[0038] In an exemplary embodiment, the telephoto mobile phone lens according to this application satisfies: 0.2≤CT12 / R1≤0.3, where CT12 represents the center thickness of the first lens and R1 represents the surface radius of the object-side surface of the first lens. By satisfying 0.2≤CT12 / R1≤0.3, and controlling the center thickness and surface radius of the object-side surface of the first lens, the first lens can play a converging role, while also taking into account the center thickness to ensure the manufacturability of the lens.

[0039] In an exemplary embodiment, the telephoto lens of this application satisfies the following condition: 0.5 ≤ f / Fno*BFL ≤ 4, where f is the focal length of the telephoto lens, Fno is the aperture of the telephoto lens, and BFL is the back focal length of the telephoto lens. Satisfying 0.5 ≤ f / Fno*BFL ≤ 4, by controlling the relationship between the focal length, aperture, and back focal length of the telephoto lens, can help ensure that the back focal length of the telephoto lens is long enough to accommodate the space requirements of other components in the module, while simultaneously ensuring that the aperture of the optical imaging lens is within the required range.

[0040] However, those skilled in the art will understand that the number of lenses constituting the optical imaging lens can be varied to obtain the various results and advantages described herein without departing from the technical solutions claimed in this application. For example, although four lenses are described as an example in the embodiments, the optical imaging lens is not limited to including four lenses. If desired, the optical imaging lens may also include other numbers of lenses.

[0041] The following describes in further detail, with reference to the accompanying drawings, specific embodiments of a telephoto mobile phone lens applicable to the above-described embodiments.

[0042] Example 1

[0043] The following is for reference Figures 1 to 2F This application describes a telephoto mobile phone lens according to Embodiment 1. Figure 1 A schematic diagram of the structure of a telephoto mobile phone lens according to Embodiment 1 of this application is shown.

[0044] like Figure 1As shown, the telephoto mobile phone lens includes, in order from the object side to the image side, an object plane 1, an aperture 2, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a prism E5, a filter E6, and an image plane 15.

[0045] The first lens E1 has positive optical power, with its object-side surface 3 being convex and its image-side surface 4 being convex. The second lens E2 has negative optical power, with its object-side surface 5 being convex and its image-side surface 6 being concave. The third lens E3 has negative optical power, with its object-side surface 7 being convex and its image-side surface 8 being concave. The fourth lens E4 has negative optical power, with its object-side surface 9 being concave and its image-side surface 10 being convex. The prism E5 has an object-side surface 11 and an image-side surface 12. The filter E6 has an object-side surface 13 and an image-side surface 14. Light from the object passes sequentially through surfaces 1 to 14 and is finally imaged on the imaging surface 15.

[0046] Table 1 shows the basic parameters of the telephoto mobile phone lens of Example 1, where the units for radius of curvature, thickness, height, and focal length are all millimeters (mm).

[0047] Table 1:

[0048]

[0049] In Embodiment 1, the object-side surface and image-side surface of any one of the first to fourth lenses 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:

[0050]

[0051] 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 1 above); k is the conic coefficient; Ai is the i-th order correction coefficient of the aspherical surface. Table 2 gives the higher-order coefficients A2, A4, A6, A8, A10, A12, A14 and A16 that can be used for each aspherical mirror 1□8 in Example 1.

[0052] Table 2:

[0053]

[0054] In this embodiment, the focal length f of the telephoto lens is 13.5mm, the equivalent focal length is 72.9mm, the operating wavelength is 470-650nm, the aperture is 2.37mm, the imaging circle is 4.235mm, the field of view is 35°, the total optical length is 5.78mm, and the number of lenses is 4.

[0055] Figure 2A The MTF curve of the telephoto mobile phone lens of Example 1 is shown. The MTF (Modulation Transfer Function) curve is the change of the lens's ability to reproduce the details of the subject onto the image plane as a function of spatial frequency. The MTF curve is close to the diffraction limit, indicating good performance. Figure 2B The diagram shows the relative illuminance and image height of the telephoto mobile phone lens of Example 1, which represents information on the change in transmittance in the vertical direction. The relative illuminance is greater than 75%, and the image brightness is uniform. Figure 2C The field curvature diagram of the telephoto mobile phone lens of Example 1 is shown. The field curvature is less than 0.18mm, indicating good correction. Figure 2D The distortion diagram of the telephoto mobile phone lens of Example 1 is shown. The distortion is less than 2%, and the correction is very good. Figure 2E The diagram shows the axial aberration of the telephoto mobile phone lens of Example 1. In the example, with an aperture radius of 2.85 mm and an aperture of 0.707 mm, the focal point deviation formed by light rays of different wavelengths along the optical axis on the focal plane is less than 0.05 mm, indicating good correction. Figure 2F The diagram shows the transverse chromatic aberration of the telephoto mobile phone lens of Example 1. In the example, at a maximum field of view of 4.235mm, the focal deviation of different wavelengths of light formed on the imaging plane along a direction perpendicular to the optical axis is ±2.5μm, indicating good correction. According to... Figures 2A to 2F It can be seen that the telephoto mobile phone lens given in Example 1 can achieve good image quality.

[0056] Example 2

[0057] The following is for reference Figures 3 to 4F This application describes a telephoto mobile phone lens according to Embodiment 2. In this embodiment, for the sake of brevity, descriptions similar to those in Embodiment 1 are omitted. Figure 3 A schematic diagram of the structure of a telephoto mobile phone lens according to Embodiment 2 of this application is shown.

[0058] like Figure 3 As shown, the telephoto mobile phone lens includes, in order from the object side to the image side, an object plane 1, an aperture 2, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a prism E5, a filter E6, and an image plane 15.

[0059] The first lens E1 has positive optical power, with its object-side surface 3 being convex and its image-side surface 4 being convex. The second lens E2 has negative optical power, with its object-side surface 5 being concave and its image-side surface 6 being concave. The third lens E3 has negative optical power, with its object-side surface 7 being convex and its image-side surface 8 being concave. The fourth lens E4 has negative optical power, with its object-side surface 9 being concave and its image-side surface 10 being convex. The prism E5 has an object-side surface 11 and an image-side surface 12. The filter E6 has an object-side surface 13 and an image-side surface 14. Light from the object passes sequentially through surfaces 1 to 14 and is finally imaged on the imaging surface 15.

[0060] Table 3 shows the basic parameters of the telephoto mobile phone lens of Example 1, where the units for radius of curvature, thickness, height, and focal length are all millimeters (mm).

[0061] Table 3:

[0062]

[0063]

[0064] Table 4 shows the higher-order coefficients that can be used for each aspherical mirror in Example 2, wherein each aspherical surface shape can be defined by formula (1) given in Example 1 above.

[0065] Table 4:

[0066]

[0067] In this embodiment, the focal length f of the telephoto lens is 13.8mm, the equivalent focal length is 74.5mm, the operating wavelength is 470-650nm, the aperture is 2.4mm, the imaging circle is 4.235mm, the field of view is 33°, the total optical length is 6.17mm, and the number of lenses is 4.

[0068] Figure 4A The MTF curve of the telephoto mobile phone lens in Example 2 is shown. The MTF (Modulation Transfer Function) curve is the change in the fidelity of the lens in reproducing the details of the subject onto the image plane as a function of spatial frequency. The MTF curve is close to the diffraction limit, indicating good performance. Figure 4B The diagram shows the relative illumination and image height of the telephoto mobile phone lens in Example 2, which represents information on the change in transmittance in the vertical direction. The relative illumination is greater than 80%, and the image brightness is uniform. Figure 4C The field curvature diagram of the telephoto mobile phone lens of Example 2 is shown. The field curvature is less than 0.5mm, indicating good correction. Figure 4DThe distortion diagram of the telephoto mobile phone lens of Example 2 is shown. The distortion is less than 2%, and the correction is very good. Figure 4E The diagram shows the axial aberration of the telephoto mobile phone lens of Example 2. In the example, when the pupil radius is 3mm and the aperture is 0.707mm, the focal point deviation formed by different wavelengths of light along the optical axis on the focal plane is less than 0.5mm, which is well corrected. Figure 4F The diagram shows the transverse chromatic aberration of the telephoto mobile phone lens of Example 2. In the example, at a maximum field of view of 16.27°, the focal deviation of different wavelengths of light formed on the imaging plane along a direction perpendicular to the optical axis is ±2.2 μm, indicating good correction. According to... Figures 4A to 4F It can be seen that the telephoto mobile phone lens given in Example 2 can achieve good image quality.

[0069] In summary, Examples 1 and 2 satisfy the relationships shown in Table 5.

[0070] Table 5:

[0071]

[0072] 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. A long-focus mobile phone lens, characterized in that, The first lens, the second lens, the third lens and the fourth lens are sequentially arranged along the optical axis from the object side to the image side, wherein the lenses with refractive powers are four pieces; The first lens has positive refractive power, the object side surface and the image side surface of the first lens are convex, the second lens has negative refractive power, the object side surface of the second lens is convex or concave, and the image side surface is concave, the third lens has negative refractive power, the object side surface of the third lens is convex, and the image side surface is concave, the fourth lens has negative refractive power, the object side surface of the fourth lens is concave, and the image side surface is convex; the back focal length BFL of the long-focus mobile phone lens and the aperture R8 of the image side surface of the fourth lens satisfy: 0 < BFL / R8 < 0.2; The refractive index N1 of the first lens, the refractive index N2 of the second lens, the refractive index N3 of the third lens and the refractive index N4 of the fourth lens satisfy: Ni / N1 < 1, i is 2, 3 or 4; The central thickness CT12 of the first lens and the surface type radius R1 of the object side surface of the first lens satisfy: 0.2 ≤ CT12 / R1 ≤ 0.

3.

2. The long focus camera lens of claim 1, wherein, The Abbe number V1 of the first lens, the Abbe number V2 of the second lens, the Abbe number V3 of the third lens and the Abbe number V4 of the fourth lens satisfy: 33 ≤ |V1-V2| ≤ 34, 35 ≤ |V3-V4| ≤ 36.

3. The long focus camera lens of claim 1, wherein, The focal length f1 of the first lens, the focal length f2 of the second lens, the focal length f3 of the third lens and the focal length f4 of the fourth lens satisfy: -0.5 ≤ f1 / fi ≤ 0, i is 2, 3 or 4.

4. The long focus camera lens of claim 1, wherein, The focal length f1 of the first lens, the focal length f2 of the second lens, the focal length f3 of the third lens and the focal length f4 of the fourth lens satisfy: -67mm ≤ f2+f3+f4 ≤ -63mm.

5. The long focus camera lens of claim 1, wherein, The sag SR7 of the object side surface type of the fourth lens and the sag SR8 of the image side surface type of the fourth lens satisfy: -0.3mm ≤ SR7-SR8 ≤ 0mm.

6. The long focus camera lens of claim 1, wherein, The surface type radius R1 of the object side surface of the first lens and the surface type radius R2 of the image side surface of the first lens satisfy: -100mm ≤ (R1-R2) / R1*R2 ≤ -20mm.

7. The long focus camera lens of claim 1, wherein, The focal length f of the long-focus mobile phone lens, the aperture Fno of the long-focus mobile phone lens and the back focal length BFL of the long-focus mobile phone lens satisfy: 0.5 ≤ f / Fno*BFL ≤ 4.

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