Long focus mobile phone lens

Abstract

The present invention discloses a telephoto mobile phone lens. The telephoto mobile phone lens sequentially includes a prism and a lens assembly from the object side to the image side; the prism includes an incident surface, a reflection surface and an exit surface; the lens assembly has a positive optical power, and the first lens has a positive optical power, and the first lens is the lens closest to the object side in the lens assembly; the entrance pupil diameter dP of the telephoto mobile phone lens and the maximum waist diameter dMax of the lens assembly satisfy: 0.825 < dP / dMax < 0.863. The telephoto mobile phone lens of the present invention can achieve a large aperture while the local aperture of the lens is small, which is beneficial to the miniaturization of the lens, and thus reduces the thickness of the mobile phone.

Description

Technical Field

[0001] This invention relates to the field of optical imaging technology, and in particular to a telephoto mobile phone lens. Background Technology

[0002] Due to their long focal length, telephoto lenses in mobile phones have a relatively long overall optical length, making miniaturization difficult. To reduce phone thickness, the telephoto lens is typically mounted horizontally within the phone, thus changing the factor affecting thickness from optical length to aperture size. However, to meet light intake requirements, a large aperture is usually used, which leads to a larger lens aperture and consequently increases the phone's thickness. Therefore, a solution is needed that can achieve both a large aperture and a small aperture to address this problem. Summary of the Invention

[0003] In view of the above problems, the purpose of this invention is to provide a telephoto mobile phone lens that can achieve a large aperture while having a small local aperture, which is conducive to the miniaturization of the lens and thus reduces the thickness of the mobile phone.

[0004] This invention provides a telephoto mobile phone lens, comprising a prism and a lens assembly sequentially from the object side to the image side; the prism includes an incident surface, a reflecting surface, and an exit surface; the lens assembly has positive optical power, and a first lens has positive optical power, wherein the first lens is the lens closest to the object side in the lens assembly; the entrance pupil diameter dP of the telephoto mobile phone lens and the maximum waist diameter dMax of the lens assembly satisfy: 0.825 <dP / dMax<0.863。

[0005] Optionally, the total optical length (TTL) and focal length (f) of the telephoto mobile phone lens satisfy: 0.9999≤TTL / f≤1.0002.

[0006] Optionally, the lens assembly includes multiple lenses, including a first lens, a second lens, a third lens, and a fourth lens, arranged sequentially. 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: 30.2≤|V2-V1|≤33.4, 32.8≤|V4-V3|≤37.0.

[0007] Optionally, the entrance pupil diameter dP, focal length f, and the angle u' between the edge rays of the central field of view and the optical axis of the telephoto mobile phone lens satisfy: 0.0003≤|dP / (f*sinu')-1|≤0.002.

[0008] Optionally, the lens assembly includes a plurality of lenses, the plurality of lenses including two lenses arranged sequentially from the object side to the image side, namely the first lens and the second lens, wherein the edge thickness dEL1 of the first lens, the center thickness dCL1 of the first lens, the edge thickness dEL2 of the second lens and the center thickness dCL2 of the second lens satisfy: 0.16≤dEL1 / dCL1≤0.61, 1.54≤dEL2 / dCL2≤2.08.

[0009] Optionally, the focal length f1 of the first lens and the focal length f of the telephoto mobile phone lens satisfy: 0.4≤f1 / f≤0.5.

[0010] Optionally, the back focal length BFL and field of view fov of the telephoto mobile phone lens satisfy: 111.5≤BFL*fov≤113.1.

[0011] Optionally, the telephoto lens of the mobile phone further includes a filter, wherein the aperture dIR and refractive index n5 of the filter satisfy: 3.684≤dIR / n5≤3.732.

[0012] Optionally, the refractive index n2 of the second lens and the refractive index n3 of the third lens satisfy: 0.964≤n2 / n3≤1.

[0013] Optionally, the lens assembly includes multiple lenses, including three lenses arranged sequentially from the object side to the image side, namely the first lens, the second lens, and the third lens. The radius of curvature R5 of the object side of the second lens, the radius of curvature R6 of the image side of the third lens, the air gap d5 between the second lens and the third lens, and the field of view fov of the telephoto mobile phone lens satisfy: 180.4≤(R5-R6) / d5*fov≤232.6.

[0014] Optionally, the radius of curvature R2 of the object side of the first lens and the radius of curvature R3 of the image side of the first lens satisfy: -1.52≤(R2-R3) / (R2+R3)≤-1.35.

[0015] Optionally, the back focal length BFL of the telephoto lens and the total optical length TTL of the telephoto lens satisfy: 0.313≤BFL / TTL≤0.319.

[0016] Optionally, the refractive index n1 and Abbe number V1 of the first lens satisfy: 0.0095≤(n1-1) / V1≤0.0097.

[0017] The long - focal - length mobile phone lens provided by the present invention realizes that the ratio of the entrance pupil diameter dP to the waist lens diameter D is less than 0.863 by reasonably distributing the optical power of each lens of the lens assembly, and the entrance pupil diameter dP and the maximum waist diameter dMax of the long - focal - length mobile phone lens satisfy: 0.825 < dP / dMax < 0.863. That is, while achieving a large aperture, the local aperture of the lens is relatively small, which is beneficial to the miniaturization of the lens, and thus plays a role in reducing the thickness of the mobile phone. The long - focal - length mobile phone lens provided by the present invention can achieve the following beneficial effects:

[0018] 1) Designed a small - sized mobile phone long - focal - length lens with small aberration, large aperture and large target surface;

[0019] 2) Fno < 2.4 large aperture, realizing a larger light - passing amount, and the amount of information captured by the lens also increases;

[0020] 3) Large target surface, realizing a larger size of the photosensitive component, and the clarity and resolution of the lens also increase;

[0021] 4) When the telephoto ratio (optical total length / focal length) is set to be less than 1.00002, the optical total length is short, which is beneficial to the miniaturization of the lens. BRIEF DESCRIPTION OF THE DRAWINGS <000005​​​​​​​​​​​​​​​​​​​​​​​​​​The MTF curve, relative illumination and Y field of view, 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.

[0029] Figure 17 A schematic diagram of the optical structure of a telephoto mobile phone lens according to Embodiment 3 of this application is shown.

[0030] Figures 18 to 23 The MTF curve, relative illumination and Y field of view, field curvature diagram, distortion diagram, axial aberration diagram and transverse chromatic aberration diagram of the telephoto mobile phone lens of Example 3 are shown respectively. Detailed Implementation

[0031] 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.

[0032] 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.

[0033] In the accompanying drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for ease of illustration. Specifically, the shape of the sphere shown in the drawings is illustrated by way of example. That is, the shape of the sphere is not limited to that shown in the drawings. The drawings are for illustrative purposes only and are not drawn strictly to scale.

[0034] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the location of the convexity is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the location of the concaveness is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the subject is called the object-side surface of the lens, and the surface of each lens closest to the imaging plane is called the image-side surface of the lens.

[0035] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0036] The features, principles, and other aspects of the present application will be described in detail below.

[0037] Please refer to Figure 1 and Figure 2 , a telephoto mobile phone lens according to an exemplary embodiment of the present application includes a prism P1 and a lens assembly in sequence from the object side to the image side; the prism P1 includes an incident surface, a reflecting surface, and an exit surface; the lens assembly has a positive optical power, and the first lens has a positive optical power, and the first lens is the lens closest to the object side in the lens assembly; the entrance pupil diameter dP of the telephoto mobile phone lens and the maximum waist diameter dMax of the lens assembly satisfy: 0.825 < dP / dMax < 0.863.

[0038] Specifically, the telephoto mobile phone lens of this embodiment includes a prism P1 and a lens assembly. Light from an object sequentially passes through the prism P1 and the lens assembly and forms an image on the imaging surface IMG. The prism P1 serves to deflect light. The incident surface and the exit surface of the prism P1 are the light-incident side and the light-exit side respectively, and the reflecting surface of the prism P1 reflects the light entering the prism P1 to deflect the light. The lens assembly has a positive optical power to form a clear real image on the imaging surface IMG; and the first lens has a positive optical power. The first lens is the lens closest to the object side in the lens assembly. This first lens plays a major role in converging light in the entire optical system, and its material properties can be selected to have a low refractive index and a high Abbe number to reduce the introduction of aberration. As Figure 1 shown, the lens assembly includes a plurality of lenses, and for example, sequentially includes a first lens L1, a second lens L2, a third lens L3, and a fourth lens L4. Then the waist 110 of the lens assembly is located between the first lens L1 and the fourth lens L4, that is, at the positions of the second lens L2 and the third lens L3. The waist 110 of the lens assembly can be set to make the local aperture of the lens smaller. However, the present application does not limit the lens assembly to only be Figure 1 the example of four lenses, that is, it can also be lenses of other numbers, without specific limitation, and all are within the protection scope of the present application. By reasonably distributing the optical powers of the lenses of the lens assembly, and the entrance pupil diameter dP of the telephoto mobile phone lens and the maximum waist diameter dMax of the lens assembly satisfy: 0.825 < dP / dMax < 0.863, it can be achieved that the ratio of the entrance pupil diameter dP to the waist lens diameter D is less than 0.863, that is, while achieving a large aperture, the local aperture of the lens is smaller, which is beneficial to the miniaturization of the lens, and further plays a role in reducing the thickness of the mobile phone.

[0039] In an exemplary embodiment, as Figure 2As shown, the telephoto mobile phone lens according to this application satisfies 0.9999≤TTL / f≤1.0002; where the total optical length of the telephoto mobile phone lens is TTL, and the focal length of the telephoto mobile phone lens is f. By controlling the total optical length TTL and focal length f of the telephoto mobile phone lens, the zoom ratio can be controlled. The zoom ratio is the ratio of the total optical length to the focal length of the telephoto mobile phone lens. If the zoom ratio is small, the total optical length of the telephoto mobile phone lens is short, which is beneficial for lens miniaturization.

[0040] In an exemplary embodiment, according to the telephoto mobile phone lens of this application, prism P1 is a right-angled isosceles prism. The two right-angled surfaces of prism P1 are the incident surface and the exit surface of prism P1, respectively. The inclined surface of prism P1 is a reflecting surface used to deflect light by 90° for use in an L-shaped horizontal structure; a reflective film may be provided on the reflecting surface.

[0041] In an exemplary embodiment, according to the telephoto mobile phone lens of this application, such as Figure 1 As shown, the lens assembly includes multiple lenses: a first lens L1, a second lens L2, a third lens L3, and a fourth lens L4. These lenses are arranged sequentially to satisfy 30.2 ≤ |V2 - V1| ≤ 33.4 and 32.8 ≤ |V4 - V3| ≤ 37.0. Specifically, the Abbe number of the first lens L1 is V1, the second lens L2 is V2, the third lens L3 is V3, and the fourth lens L4 is V4. By controlling the Abbe numbers V1, V2, V3, and V4 of the first lens L1, second lens L2, third lens L3, and fourth lens L4, a combination of high and low Abbe numbers can be formed, which can better correct chromatic aberration.

[0042] In an exemplary embodiment, the telephoto mobile phone lens according to this application satisfies 0.0003≤|dP / (f*sinu')-1|≤0.002; where the entrance pupil diameter of the telephoto mobile phone lens is dP, the focal length of the telephoto mobile phone lens is f, and the angle between the edge rays of the central field of view and the optical axis is u'. By satisfying 0.0003≤|dP / (f*sinu')-1|≤0.002, and by controlling the entrance pupil diameter dP, the focal length f, and the angle u' between the edge rays of the central field of view and the optical axis, a combination of high and low Abbe numbers can be formed, which can effectively control the spherical aberration and coma of the paraxial optical system.

[0043] In an exemplary implementation, such as Figure 2As shown, according to the telephoto mobile phone lens of this application, the lens assembly includes multiple lenses, including two lenses arranged sequentially from the object side to the image side, namely the first lens and the second lens, which can satisfy 0.16≤dEL1 / dCL1≤0.61, 1.54≤dEL2 / dCL2≤2.08; wherein, the edge thickness of the first lens L1 is dEL1, the center thickness of the first lens L1 is dCL1, the edge thickness of the second lens L2 is dEL2, and the center thickness of the second lens L2 is dCL2. Satisfying 0.16≤dEL1 / dCL1≤0.61 and 1.54≤dEL2 / dCL2≤2.08, by controlling the edge thickness dEL1 of the first lens L1, the center thickness dCL1 of the first lens L1, the edge thickness dEL2 of the second lens L2, and the center thickness dCL2 of the second lens L2, such that the center thickness dCL1 of the first lens L1 is greater than the edge thickness dEL1, and the center thickness dCL2 of the second lens L2 is less than the edge thickness dEL2, the optical path of the edge light rays can be increased, which is beneficial to the correction of field curvature.

[0044] In an exemplary embodiment, the telephoto mobile phone lens according to this application satisfies 0.4≤f1 / f≤0.5; wherein the focal length of the first lens L1 is f1 and the focal length of the telephoto mobile phone lens is f. By satisfying 0.4≤f1 / f≤0.5 and controlling the focal lengths f1 and f of the first lens L1 and the telephoto mobile phone lens, the first lens L1 can be allocated the largest proportion of optical power in the overall optical power distribution, primarily serving to converge the light rays of the entire system, while playing a relatively minor role in optimizing aberrations.

[0045] In an exemplary implementation, such as Figure 2 As shown, the telephoto mobile phone lens according to this application satisfies 111.5≤BFL*fov≤113.1; where the back focal length of the telephoto mobile phone lens is BFL, and the field of view of the telephoto mobile phone lens is fov. By satisfying 111.5≤BFL*fov≤113.1 and controlling the back focal length BFL and the field of view fov of the telephoto mobile phone lens, a structural balance between the back focal length and the field of view can be achieved. The short back focal length meets the requirements of a large field of view and a large target surface, making the lens size more compact and conducive to lens miniaturization.

[0046] In an exemplary embodiment, the telephoto mobile phone lens according to this application includes a lens assembly comprising multiple lenses, including a first lens L1, a second lens L2, a third lens L3, and a fourth lens L4, arranged sequentially. The first lens L1 has positive optical power; the second lens L2 has negative optical power; the third lens L3 has positive optical power; and the fourth lens L4 has negative optical power, thereby achieving the purpose of reducing the aperture of the optical system and meeting the design requirements of a large aperture and a large target surface. Furthermore, the focal length f1 of the first lens L1 and the focal length f2 of the second lens L2 satisfy f1 / f2<0, and the focal length f3 of the third lens L3 and the focal length f4 of the fourth lens L4 satisfy f3 / f4<0. These lenses are arranged sequentially in the form of positive and negative focal lengths (i.e., positive and negative optical powers), which is beneficial for the correction of monochromatic aberration.

[0047] In an exemplary embodiment, the telephoto mobile phone lens according to this application further includes a filter IR, which satisfies 3.684≤dIR / n5≤3.732; wherein the aperture of the filter IR is dIR, and the refractive index of the filter IR is n5. By satisfying 3.684≤dIR / n5≤3.732 and controlling the aperture dIR and refractive index n5 of the filter IR, placing the filter IR after the imaging system facilitates increasing the optical path and compressing the back focal distance, achieving a large aperture and miniaturization. Furthermore, the filter IR satisfies the characteristics of low refractive index and high Abbe number, and also has the ability to correct aberrations generated by the imaging system.

[0048] In an exemplary embodiment, the telephoto mobile phone lens according to this application includes a lens assembly comprising multiple lenses, the multiple lenses including three lenses arranged sequentially from the object side to the image side, namely a first lens L1, a second lens L2, and a third lens L3, which can satisfy 0.964≤n2 / n3≤1; wherein, the refractive index of the second lens L2 is n2, and the refractive index of the third lens L3 is n3. By satisfying 0.964≤n2 / n3≤1, and by controlling the refractive index n2 of the second lens L2 and the refractive index n3 of the third lens L3, the ratio of the refractive indices of the second lens L2 and the third lens L3 is controlled to be around 1, thereby smoothing the light transition in the optical system, introducing less primary aberration, and benefiting the aberration correction of the entire optical system.

[0049] In an exemplary embodiment, the telephoto mobile phone lens according to this application includes a lens assembly comprising multiple lenses, the multiple lenses including three lenses arranged sequentially from the object side to the image side, namely a first lens L1, a second lens L2, and a third lens L3, which can satisfy 180.4≤(R5-R6) / d5*fov≤232.6; wherein, the radius of curvature of the object side of the second lens L2 is R5, the radius of curvature of the image side of the third lens L3 is R6, the air gap between the second lens L2 and the third lens L3 is d5, and the field of view of the telephoto mobile phone lens is fov. By satisfying 180.4≤(R5-R6) / d5*fov≤232.6, and by controlling the radius of curvature R5 of the object side of the second lens L2, the radius of curvature R6 of the image side of the third lens L3, the air gap d5 between the second lens L2 and the third lens L3, and the field of view fov of the telephoto mobile phone lens, the radius of curvature of the second lens L2 and the third lens L3 and the air gap can be balanced, making the optical path of the entire optical system longer and the waist diameter smaller, which is beneficial to the miniaturization of the lens.

[0050] In an exemplary embodiment, the telephoto mobile phone lens according to this application satisfies -1.52≤(R2-R3) / (R2+R3)≤-1.35; wherein, the radius of curvature of the object-side surface of the first lens L1 is R2, and the radius of curvature of the image-side surface of the first lens L1 is R3. By satisfying -1.52≤(R2-R3) / (R2+R3)≤-1.35, and by controlling the radius of curvature R2 of the object-side surface and R3 of the image-side surface of the first lens L1, the shape of the first lens L1 can be controlled, resulting in a larger proportion of optical power, smaller introduced off-axis aberrations, and effective correction of spherical aberration in the system.

[0051] In an exemplary implementation, such as Figure 2 As shown, the telephoto mobile phone lens according to this application satisfies 0.313≤BFL / TTL≤0.319; where the back focal length of the telephoto mobile phone lens is BFL, and the total optical length of the telephoto mobile phone lens is TTL. By satisfying 0.313≤BFL / TTL≤0.319 and controlling the back focal length BFL and the total optical length TTL of the telephoto mobile phone lens, the proportion of the back focal length in the entire optical system can be made smaller, resulting in a more compact lens structure and a significant improvement in the miniaturization of the total optical length of the system.

[0052] In an exemplary embodiment, the telephoto mobile phone lens according to this application satisfies 0.0095≤(n1-1) / V1≤0.0097; wherein the refractive index of the first lens L1 is n1, and the Abbe number of the first lens L1 is V1. By satisfying 0.0095≤(n1-1) / V1≤0.0097 and controlling the refractive index n1 and Abbe number V1 of the first lens L1, the first lens L1 adopts a low refractive index and high Abbe number, thus introducing less chromatic aberration, which is beneficial for chromatic aberration correction of the entire optical system.

[0053] In an exemplary embodiment, the telephoto mobile phone lens according to this application further includes an aperture stop STO, which may be disposed on the object side of the first lens.

[0054] However, those skilled in the art will understand that the number of lenses constituting the telephoto lens can be changed 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 embodiment, the telephoto lens is not limited to including four lenses. If desired, the telephoto lens may also include other numbers of lenses.

[0055] 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.

[0056] Example 1

[0057] The following is for reference Figure 3 This application describes a telephoto mobile phone lens according to Embodiment 1. Figure 3 A schematic diagram of the optical structure of a telephoto mobile phone lens according to Embodiment 1 of this application is shown.

[0058] like Figure 3 As shown, the telephoto mobile phone lens includes, from the object side to the image side, a prism P1 (…). Figure 2 Not shown, please refer to Figure 1 The lens assembly includes a first lens L1, a second lens L2, a third lens L3, and a fourth lens L4. An aperture stop STO may be positioned on the object side of the first lens L1. A filter IR may be positioned between the fourth lens L4 and the imaging plane IMG.

[0059] The first lens L1 has positive optical power, with both its object-side and image-side surfaces being convex. The second lens L2 has negative optical power, with both its object-side and image-side surfaces being convex. The third lens L3 has positive optical power, with both its object-side and image-side surfaces being concave. The fourth lens L4 has negative optical power, with both its object-side and image-side surfaces being convex. The filter IR has both an object-side and an image-side surface. Light from the object passes sequentially through prism P1, aperture STO, first lens L1, second lens L2, third lens L3, fourth lens L4, and filter IR before reaching the imaging plane IMG.

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

[0061] Table 1:

[0062]

[0063] Wherein, L1-R1 represents the object-side surface of the first lens L1, L1-R2 represents the image-side surface of the first lens L1, L2-R1 represents the object-side surface of the second lens L2, L2-R2 represents the image-side surface of the second lens L2, L3-R1 represents the object-side surface of the third lens L3, L3-R2 represents the image-side surface of the third lens L3, L4-R1 represents the object-side surface of the fourth lens L4, L4-R2 represents the image-side surface of the fourth lens L4, IR-R1 represents the object-side surface of the filter IR, and IR-R2 represents the image-side surface of the filter IR.

[0064] In Example 1, the object-side surface and image-side surface of any one of the first lens L1 to the fourth lens L4 are both even-order aspherical surfaces, which can be optimized using Zemax design software. In Zemax, the equations of each even-order aspherical surface can be limited by, but are not limited to, the following formulas:

[0065] (1)

[0066] Where Z represents the height along the optical axis, c represents the radius of curvature, h represents the aperture along the radial direction, k represents the conic coefficient, A2 represents the quadratic coefficient of the even-order aspherical surface, A4 represents the quartic coefficient of the even-order aspherical surface, A6 represents the sixth-order coefficient of the even-order aspherical surface, A8 represents the eighth-order coefficient of the even-order aspherical surface, A10 represents the tenth-order coefficient of the even-order aspherical surface, A12 represents the twelfth-order coefficient of the even-order aspherical surface, A14 represents the fourteenth-order coefficient of the even-order aspherical surface, and A16 represents the sixteenth-order coefficient of the even-order aspherical surface.

[0067] Table 2 provides the conic coefficient k and the higher-order aspheric coefficients A2, A4, A6, A8, and A6 that can be used for each even-order aspheric surface in Example 1. 10, A 12 , A 14 Japanese A 16 .

[0068] Table 2:

[0069]

[0070] In this embodiment, the focal length of the telephoto lens is 10.7mm, the equivalent focal length is 71.9mm, the operating wavelength is 470-650nm, the imaging circle diameter is 7mm, the field of view is 33.3°, the total optical length is 10.7mm, and the maximum waist diameter is 5.7mm. The relationship between the total optical length (TTL) and focal length (f) of the telephoto lens is: TTL / f = 0.9999. The relationships between the Abbe numbers V1 of the first lens L1, V2 of the second lens L2, V3 of the third lens L3, and V4 of the fourth lens L4 are: |V2-V1| = 33.4, |V4-V3| = 36.4. The relationship between the focal length f1 of the first lens L1 and the focal length f of the telephoto lens is: f1 / f = 0.5. The relationship between the back focal length BFL and the field of view fov of a telephoto mobile phone lens is: BFL*fov=113.1. The relationship between the focal length f1 of the first lens L1 and the focal length f2 of the second lens L2 is: f1 / f2=-0.91<0. The relationship between the focal length f3 of the third lens L3 and the focal length f4 of the fourth lens L4 is: f3 / f4=-0.92<0. The relationship between the aperture dIR and the refractive index n5 of the filter IR is: dIR / n5=3.732. The relationship between the refractive index n2 of the second lens L2 and the refractive index n3 of the third lens L3 is: n2 / n3=0.982. The relationship between the radius of curvature R5 of the object-side surface of the second lens L2, the radius of curvature R6 of the image-side surface of the third lens L3, the air gap d5 between the second lens L2 and the third lens L3, and the field of view fov of the telephoto lens is: (R5-R6) / d5*fov = 232.6. The relationship between the radius of curvature R2 of the object-side surface of the first lens L1 and the radius of curvature R3 of the image-side surface of the first lens L1 is: (R2-R3) / (R2+R3) = -1.52. The relationship between the back focal length BFL of the telephoto lens and the total optical length TTL of the telephoto lens is: BFL / TTL = 0.317. The relationship between the entrance pupil diameter dP and the maximum waist diameter dMax of the telephoto lens is: dP / dMax = 0.825. The relationship between the entrance pupil diameter dP, focal length f, and the angle u' between the marginal ray and the optical axis of the central field of view of a telephoto mobile phone lens is: |dP / (f*sinu')-1|=0.0020. The relationship between the refractive index n1 and Abbe number V1 of the first lens L1 is: (n1-1) / V1=0.0095. The relationship between the edge thickness dEL1, center thickness dCL1, edge thickness dEL2, and center thickness dCL2 of the second lens L2 is: dEL1 / dCL1=0.61, dEL2 / dCL2=2.08.

[0071] Figure 4The MTF curve of the telephoto mobile phone lens of Example 1 is shown. The MTF (Modulation Transfer Function) curve is the change in the degree to which the lens reproduces the details of the subject onto the imaging plane IMG as the spatial frequency changes. When the MTF curve is close to the diffraction limit, the lens imaging effect is good. Figure 5 The relative illumination and Y-field diagram of the telephoto mobile phone lens of Example 1 are shown. The relative illumination is greater than 75%, and the brightness of the image is uniform. Figure 6 The field curvature diagram of the telephoto mobile phone lens of Example 1 is shown. The field curvature is less than 0.06mm, indicating good correction. Figure 7 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 8 The diagram shows the axial aberration of the telephoto mobile phone lens of Example 1. When the pupil radius is 2.2300 mm, the focal deviation of light rays of different wavelengths along the optical axis on the focal plane is less than 0.03 mm within the aperture, and the axial aberration is 0.707 mm, which is well corrected. Figure 9 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 17.6280Deg, the focal deviation of different wavelengths of light formed on the imaging plane along a direction perpendicular to the optical axis is within ±2μm, indicating good correction. According to... Figures 4 to 9 It can be seen that the telephoto mobile phone lens given in Example 1 can achieve good image quality.

[0072] Example 2

[0073] The following is for reference Figure 10 This application describes a telephoto mobile phone lens according to Embodiment 2. Figure 10 A schematic diagram of the optical structure of a telephoto mobile phone lens according to Embodiment 2 of this application is shown. In this embodiment, for the sake of brevity, descriptions similar to those in Embodiment 1 are omitted.

[0074] like Figure 10 As shown, the telephoto mobile phone lens includes, from the object side to the image side, a prism P1 (…). Figure 4 Not shown, please refer to Figure 1 The lens assembly includes a first lens L1, a second lens L2, a third lens L3, and a fourth lens L4. An aperture stop STO may be positioned on the object side of the first lens L1. A filter IR may be positioned between the fourth lens L4 and the imaging plane IMG.

[0075] The first lens L1 has positive optical power, with both its object-side and image-side surfaces being convex. The second lens L2 has negative optical power, with both its object-side and image-side surfaces being convex. The third lens L3 has positive optical power, with both its object-side and image-side surfaces being concave. The fourth lens L4 has negative optical power, with both its object-side and image-side surfaces being convex. The filter IR has both an object-side and an image-side surface. Light from the object passes sequentially through prism P1, aperture STO, first lens L1, second lens L2, third lens L3, fourth lens L4, and filter IR before reaching the imaging plane IMG.

[0076] Table 3 shows the basic parameters of the telephoto mobile phone lens of Example 2, where the units for radius of curvature, thickness, aperture, focal length, and edge thickness are all millimeters (mm).

[0077] Table 3:

[0078]

[0079] Table 4 gives the conic coefficient k and higher-order aspheric coefficients that can be used for each even-order aspheric surface in Example 2, wherein each even-order aspheric surface can be defined by formula (1) given in Example 1 above.

[0080] Table 4:

[0081]

[0082] In this embodiment, the focal length of the telephoto lens is 10.65mm, the equivalent focal length is 71mm, the operating wavelength is 470-650nm, the imaging circle diameter is 7mm, the field of view is 33.3°, the total optical length is 10.7mm, and the maximum waist diameter is 5.7mm. The relationship between the total optical length (TTL) and focal length (f) of the telephoto lens is: TTL / f = 1.000001. The relationships between the Abbe numbers V1 of the first lens L1, V2 of the second lens L2, V3 of the third lens L3, and V4 of the fourth lens L4 are: |V2-V1| = 30.2, |V4-V3| = 32.8. The relationship between the focal length f1 of the first lens L1 and the focal length f of the telephoto lens is: f1 / f = 0.4. The relationship between the back focal length BFL and the field of view fov of a telephoto mobile phone lens is: BFL*fov=111.5. The relationship between the focal length f1 of the first lens L1 and the focal length f2 of the second lens L2 is: f1 / f2=-0.67<0. The relationship between the focal length f3 of the third lens L3 and the focal length f4 of the fourth lens L4 is: f3 / f4=-3.13<0. The relationship between the aperture dIR and the refractive index n5 of the filter IR is: dIR / n5=3.725. The relationship between the refractive index n2 of the second lens L2 and the refractive index n3 of the third lens L3 is: n2 / n3=0.982. The relationship between the radius of curvature R5 of the object-side surface of the second lens L2, the radius of curvature R6 of the image-side surface of the third lens L3, the air gap d5 between the second lens L2 and the third lens L3, and the field of view fov of the telephoto lens is: (R5-R6) / d5*fov = 180.4. The relationship between the radius of curvature R2 of the object-side surface of the first lens L1 and the radius of curvature R3 of the image-side surface of the first lens L1 is: (R2-R3) / (R2+R3) = -1.36. The relationship between the back focal length BFL of the telephoto lens and the total optical length TTL of the telephoto lens is: BFL / TTL = 0.313. The relationship between the entrance pupil diameter dP and the maximum waist diameter dMax of the telephoto lens is: dP / dMax = 0.827. The relationship between the entrance pupil diameter dP, focal length f, and the angle u' between the edge ray and the optical axis of the central field of view of a telephoto mobile phone lens is: |dP / (f*sinu')-1|=0.0003. The relationship between the refractive index n1 and Abbe number V1 of the first lens L1 is: (n1-1) / V1=0.0097. The relationship between the edge thickness dEL1, center thickness dCL1, edge thickness dEL2, and center thickness dCL2 of the second lens L2 is: dEL1 / dCL1=0.25, dEL2 / dCL2=1.54.

[0083] Figure 11The MTF curve of the telephoto mobile phone lens in Example 2 is shown. The MTF (Modulation Transfer Function) curve is the change in the degree to which the lens reproduces the details of the subject onto the imaging plane IMG as the spatial frequency changes. When the MTF curve is close to the diffraction limit, the lens imaging effect is better. Figure 12 The relative illumination and Y-field diagram of the telephoto mobile phone lens of Example 2 are shown. The relative illumination is greater than 75%, and the brightness of the image is uniform. Figure 13 The field curvature diagram of the telephoto mobile phone lens of Example 2 is shown. The field curvature is less than 0.03mm, indicating good correction. Figure 14 The distortion diagram of the telephoto mobile phone lens of Example 2 is shown. The distortion is less than 3%, and the correction is very good. Figure 15 The diagram shows the axial aberration of the telephoto mobile phone lens of Example 2. In the example, when the pupil radius is 2.2300 mm, the focal point deviation formed by different wavelengths of light along the optical axis on the focal plane is 0.707 mm, and the axial aberration is less than 0.03 mm within the aperture, which is well corrected. Figure 16 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 3.4000 mm, the focal deviation of different wavelengths of light formed on the imaging plane along a direction perpendicular to the optical axis is within ±2 μm, indicating good correction. According to... Figures 11 to 16 It can be seen that the telephoto mobile phone lens given in Example 2 can achieve good image quality.

[0084] Example 3

[0085] The following is for reference Figure 17 This application describes a telephoto mobile phone lens according to Embodiment 3. Figure 17 A schematic diagram of the optical structure of a telephoto mobile phone lens according to Embodiment 3 of this application is shown. In this embodiment, for the sake of brevity, descriptions similar to those in Embodiment 1 are omitted.

[0086] like Figure 17 As shown, the telephoto mobile phone lens includes, from the object side to the image side, a prism P1 (…). Figure 17 Not shown, please refer to Figure 1 The lens assembly includes a first lens L1, a second lens L2, a third lens L3, and a fourth lens L4. An aperture stop STO may be positioned on the object side of the first lens L1. A filter IR may be positioned between the fourth lens L4 and the imaging plane IMG.

[0087] The first lens L1 has positive optical power, with both its object-side and image-side surfaces being convex. The second lens L2 has negative optical power, with both its object-side and image-side surfaces being concave. The third lens L3 has positive optical power, with both its object-side and image-side surfaces being concave. The fourth lens L4 has negative optical power, with both its object-side and image-side surfaces being convex. The filter IR has both an object-side and an image-side surface. Light from the object passes sequentially through prism P1, aperture STO, first lens L1, second lens L2, third lens L3, fourth lens L4, and filter IR before reaching the imaging plane IMG.

[0088] Table 5 shows the basic parameters of the telephoto mobile phone lens of Example 3, where the units for radius of curvature, thickness, aperture, focal length, and edge thickness are all millimeters (mm).

[0089] Table 5:

[0090]

[0091] Table 6 gives the conic coefficient k and higher-order aspheric coefficients that can be used for each even-order aspheric surface in Example 3, wherein each even-order aspheric surface can be defined by formula (1) given in Example 1 above.

[0092] Table 6:

[0093]

[0094] In this embodiment, the focal length of the telephoto lens is 10.5mm, the equivalent focal length is 70.5mm, the operating wavelength is 470-650nm, the imaging circle diameter is 6.9mm, the field of view is 33.3°, the total optical length is 10.5mm, and the maximum waist diameter is 5.6mm. The relationship between the total optical length (TTL) and focal length (f) of the telephoto lens is: TTL / f = 1.000200. The relationships between the Abbe numbers V1 of the first lens L1, V2 of the second lens L2, V3 of the third lens L3, and V4 of the fourth lens L4 are: |V2-V1| = 30.2, |V4-V3| = 37.0. The relationship between the focal length f1 of the first lens L1 and the focal length f of the telephoto lens is: f1 / f = 0.5. The relationship between the back focal length BFL and the field of view fov of the telephoto lens is: BFL*fov = 111.5. The relationship between the focal length f1 of the first lens L1 and the focal length f2 of the second lens L2 is: f1 / f2 = -0.65 < 0. The relationship between the focal length f3 of the third lens L3 and the focal length f4 of the fourth lens L4 is: f3 / f4 = -3.61 < 0. The relationship between the aperture dIR and refractive index n5 of the filter IR is: dIR / n5 = 3.684. The relationship between the refractive index n2 of the second lens L2 and the refractive index n3 of the third lens L3 is: n2 / n3 = 0.964. The relationship between the radius of curvature R5 of the object-side surface of the second lens L2, the radius of curvature R6 of the image-side surface of the third lens L3, the air gap d5 between the second lens L2 and the third lens L3, and the field of view fov of the telephoto lens is: (R5-R6) / d5*fov = 181.1. The relationship between the radius of curvature R2 of the object-side surface of the first lens L1 and the radius of curvature R3 of the image-side surface of the first lens L1 is: (R2-R3) / (R2+R3) = -1.35. The relationship between the back focal length BFL of the telephoto lens and the total optical length TTL of the telephoto lens is: BFL / TTL = 0.319. The relationship between the entrance pupil diameter dP and the maximum waist diameter dMax of the telephoto lens is: dP / dMax = 0.863. The relationship between the entrance pupil diameter dP, focal length f, and the angle u' between the edge ray and the optical axis of the central field of view of a telephoto mobile phone lens is: |dP / (f*sinu')-1|=0.0014. The relationship between the refractive index n1 and Abbe number V1 of the first lens L1 is: (n1-1) / V1=0.0095. The relationship between the edge thickness dEL1, center thickness dCL1, edge thickness dEL2, and center thickness dCL2 of the second lens L2 is: dEL1 / dCL1=0.16, dEL2 / dCL2=1.57.

[0095] Figure 18 The MTF curve of the telephoto mobile phone lens in Example 3 is shown. The MTF (Modulation Transfer Function) curve is the change in the degree to which the lens reproduces the details of the subject onto the imaging plane IMG as the spatial frequency changes. When the MTF curve is close to the diffraction limit, the lens imaging effect is good. Figure 19 The relative illumination and Y-field diagram of the telephoto mobile phone lens of Example 3 are shown. The relative illumination is greater than 75%, and the brightness of the image is uniform. Figure 20 The field curvature diagram of the telephoto mobile phone lens of Example 3 is shown. The field curvature is less than 0.06mm, indicating good correction. Figure 21 The distortion diagram of the telephoto mobile phone lens of Example 3 is shown. The distortion is less than 2%, and the correction is very good. Figure 22 The diagram shows the axial aberration of the telephoto mobile phone lens of Example 3. In the example, when the pupil radius is 2.3250 mm, the focal deviation of light rays of different wavelengths along the optical axis on the focal plane is less than 0.02 mm within the aperture, and the axial aberration is 0.707 mm, which is well corrected. Figure 23 The diagram shows the transverse chromatic aberration of the telephoto mobile phone lens of Example 3. In the example, at a maximum field of view of 3.4000 mm, the focal deviation of different wavelengths of light formed on the imaging plane along a direction perpendicular to the optical axis is within ±2 μm, indicating good correction. According to... Figures 18 to 23 It can be seen that the telephoto mobile phone lens given in Example 3 can achieve good image quality.

[0096] In summary, Examples 1, 2, and 3 satisfy the relationships shown in Table 7.

[0097] Table 7:

[0098]

[0099] 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 telephoto mobile phone lens, characterized in that, It successively includes a prism and a lens assembly from the object side to the image side; The prism includes an incident surface, a reflection surface, and an exit surface; The lens assembly includes a first lens with a positive optical power, a second lens with a negative optical power, a third lens with a positive optical power, and a fourth lens with a negative optical power arranged in sequence; among them, there are four lenses with optical power; the aperture number Fno of the telephoto mobile phone lens is less than 2.4; the entrance pupil diameter dP of the telephoto mobile phone lens and the maximum waist diameter dMax of the lens assembly satisfy: 0.825 < dP / dMax < 0.863; the entrance pupil diameter dP, the focal length f, and the angle u' between the marginal ray of the central field of view and the optical axis of the telephoto mobile phone lens satisfy: 0.0003 ≤ |dP / (f * sinu') - 1| ≤ 0.

002.

2. The telephoto mobile phone lens according to claim 1, characterized in that, The overall optical length TTL and the focal length f of the telephoto mobile phone lens satisfy: 0.9999 ≤ TTL / f ≤ 1.0002.

3. The telephoto mobile phone lens according to claim 1, characterized in that, The edge thickness dEL1 of the first lens, the central thickness dCL1 of the first lens, the edge thickness dEL2 of the second lens, and the central thickness dCL2 of the second lens satisfy: 0.16 ≤ dEL1 / dCL1 ≤ 0.61, 1.54 ≤ dEL2 / dCL2 ≤ 2.

08.

4. The telephoto mobile phone lens according to claim 1, characterized in that, The focal length f1 of the first lens and the focal length f of the telephoto mobile phone lens satisfy: 0.4 ≤ f1 / f ≤ 0.

5.

5. The telephoto mobile phone lens according to claim 1, characterized in that, The back focal length BFL and the field angle fov of the telephoto mobile phone lens satisfy: 111.5 mm·° ≤ BFL * fov ≤ 113.1 mm·°.

6. The telephoto mobile phone lens according to claim 1, characterized in that, The telephoto mobile phone lens further includes a filter, and the aperture dIR and the refractive index n5 of the filter satisfy: 3.684 mm ≤ dIR / n5 ≤ 3.732 mm.

7. The telephoto mobile phone lens according to claim 1, characterized in that, The curvature radius R5 of the object side surface of the second lens, the curvature radius R6 of the image side surface of the third lens, the air gap d5 between the second lens and the third lens, and the field angle fov of the telephoto mobile phone lens satisfy: 180.4° ≤ (R5 - R6) / d5 * fov ≤ 232.6°.

8. The telephoto mobile phone lens according to claim 1, characterized in that, The curvature radius R2 of the object side surface of the first lens and the curvature radius R3 of the image side surface of the first lens satisfy: -1.52 ≤ (R2 - R3) / (R2 + R3) ≤ -1.

35.

9. The telephoto mobile phone lens according to claim 1, characterized in that, The back focal length BFL and the overall optical length TTL of the telephoto mobile phone lens satisfy: 0.313 ≤ BFL / TTL ≤ 0.319.

Images