Telephoto lens with novel structure and camera module

Abstract

The invention discloses a telephoto lens with a novel structure and a camera module. The telephoto lens with the novel structure sequentially comprises a lens assembly and a prism from an object side to an image side, the prism comprises an incident surface, a reflecting surface and an emergent surface; an included angle theta between the incident surface and the reflecting surface is greater than or equal to 39 degrees and less than or equal to 45 degrees; incident light rays penetrate through the lens assembly in the optical axis direction of the lens assembly, enter the prism from the incidence face, are reflected by the reflection face and exit to the imaging face of the imaging assembly from the exit face. According to the invention, the long-distance telephoto capability can be realized, and the length of the lens can be reduced.

Description

Technical Field

[0001] The present invention relates to the field of optical imaging technology, and in particular to a novel structure telephoto lens and camera module. Background Art

[0002] With the development of multifunctionality of various electronic products, the camera function has become an essential function of many electronic products such as smart phones, and the camera module with lens has also become an essential component of electronic products.

[0003] However, in order to achieve a longer telephoto capability, the lens needs to have a longer optical focal length. A longer optical focal length leads to a longer total optical length, which causes the lens to be too long and unable to meet the high requirements of electronic products such as mobile phones. Therefore, a solution is needed to achieve long-distance telephoto capability and reduce the length of the lens to solve this problem. Summary of the invention

[0004] In view of the above problems, an object of the present invention is to provide a new type of telephoto lens and camera module, which can achieve long-distance telephoto capability and reduce the length of the lens.

[0005] The present invention provides a new type of telephoto lens structure, which comprises a lens assembly and a prism in sequence from the object side to the image side; the prism comprises an incident surface, a reflection surface and an exit surface, the incident surface of the prism is a curved surface, and the exit surface of the prism is a plane or a curved surface; the incident light passes through the lens assembly along the optical axis direction of the lens assembly, is incident on the prism from the incident surface, is reflected by the reflection surface, and is emitted from the exit surface to the imaging surface of the imaging assembly.

[0006] Optionally, the maximum aperture Dmax of the lens assembly satisfies: Dmax≥4.6mm.

[0007] Optionally, the distance H1 from the vertex of the first lens of the lens assembly to the bottom point of the last lens, the distance H2 from the incident surface of the prism to the bottom of the prism, the distance H3 from the bottom point of the last lens of the lens assembly to the incident surface of the prism, and the system focal length f of the novel structure telephoto lens satisfy: 0.64≤(H1+H2+H3) / f≤0.75.

[0008] Optionally, a distance H1 from the vertex of the first lens of the lens assembly to the bottom point of the last lens, and a distance H3 from the bottom point of the last lens of the lens assembly to the incident surface of the prism satisfy: 0.11≤H3 / H1≤0.15.

[0009] Optionally, a distance H1 from the vertex of the first lens of the lens assembly to the bottom point of the last lens, and a distance H2 from the incident surface of the prism to the bottom of the prism, satisfy: 0.75≤H1 / H2≤0.9.

[0010] Optionally, the imaging circle diameter MIC of the novel structure telephoto lens, the angle θ between the incident surface and the reflecting surface, and the distance H2 from the incident surface of the prism to the bottom of the prism satisfy: 0.92 ≤ MIC / 2*cos(90°-2*θ) / H2≤1.18.

[0011] Optionally, an aperture DL1 of the object side surface of the first lens of the lens assembly and an aperture D10 of the incident surface of the prism satisfy: 0.93≤D10 / DL1≤1.24.

[0012] Optionally, the focal length f1 of the first lens of the lens assembly and the system focal length f of the novel structure telephoto lens satisfy: 0.54≤f1 / f≤0.96.

[0013] Optionally, the Abbe number V1 of the first lens of the lens assembly, the Abbe number V2 of the second lens of the lens assembly, the Abbe number V3 of the third lens of the lens assembly, and the Abbe number V4 of the fourth lens of the lens assembly satisfy: 12.5≤|V2-V1|≤33.3, 17.5≤|V4-V3|≤36.3.

[0014] The present invention also provides a camera module, comprising the novel structural telephoto lens mentioned above, and the imaging component arranged opposite to the exit surface of the prism.

[0015] The invention provides a new structure telephoto lens and camera module. The new structure telephoto lens includes a lens assembly and a prism from the object side to the image side in sequence; the prism includes an incident surface, a reflection surface and an exit surface, and the prism P1 not only participates in the imaging of the optical system but also realizes the folded light path of the optical system. The angle θ between the incident surface and the reflection surface of the prism P1 satisfies: 39°≤θ≤45°, which can be used to make the lowest point of the imaging surface IMG flush with the lowest point of the prism P1, so that the imaging assembly where the imaging surface IMG is located does not increase the lens length, and the length of the optical system is reduced by folding the optical system by the prism P1, which is conducive to reducing the lens length. Therefore, by reasonably allocating the focal length, thickness, spacing and refractive index of each lens of the lens assembly 100, as well as the angle and thickness of the focal length prism P1, it is possible to achieve long-distance telephoto capability and reduce the lens length. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0017] Figure 1 A schematic structural diagram of a novel telephoto lens according to an embodiment of the present application is shown; Figure 2 A schematic diagram showing the structural dimensions of a new-structure telephoto lens according to an embodiment of the present application is shown; Figure 3 A schematic diagram showing the structure of a prism in a new-structure telephoto lens according to an embodiment of the present application is shown; Figure 4 A schematic diagram of the optical path structure of a novel structure telephoto lens according to Example 1 of the present application is shown; Figures 5 to 9 The MTF curve diagram, the relationship diagram between relative illumination and field angle, the field curvature diagram, the distortion diagram and the vertical axis chromatic aberration diagram of the novel structure telephoto lens of Example 1 are respectively shown; Fig.10 A schematic diagram of the optical path structure of a novel structure telephoto lens according to Example 2 of the present application is shown; Figures 11 to 15 The MTF curve diagram, the relationship diagram between relative illumination and field angle, the field curvature diagram, the distortion diagram and the vertical axis chromatic aberration diagram of the novel structure telephoto lens of Example 2 are respectively shown; Fig.16 A schematic diagram of the optical path structure of a novel structure telephoto lens according to Example 3 of the present application is shown; Figures 17 to 21 The MTF curve diagram, the relationship diagram between relative illumination and field angle, the field curvature diagram, the distortion diagram and the vertical axis chromatic aberration diagram of the novel structure telephoto lens of Example 3 are respectively shown; Fig. 22 A schematic diagram of the optical path structure of a novel structure telephoto lens according to Example 4 of the present application is shown; Figure 23 to Figure 27 The MTF curve diagram, the relationship diagram between relative illumination and field angle, the field curvature diagram, the distortion diagram and the vertical axis chromatic aberration diagram of the novel structure telephoto lens of Example 4 are respectively shown. DETAILED DESCRIPTION

[0018] The aforementioned and other technical contents, features and effects of the present invention will be clearly presented in the following detailed description of the preferred embodiments with reference to the drawings. Through the description of the specific implementation methods, the technical means and effects adopted by the present invention to achieve the intended purpose can be more deeply and specifically understood. However, the attached drawings are only for reference and illustration, not for limiting the present invention, and some well-known parts may not be shown. In each of the drawings, the same elements are represented by similar reference numerals. For the sake of clarity, the various parts in the drawings are not necessarily drawn strictly in accordance with the actual proportions.

[0019] It will be understood that the terms “comprises,” “comprising,” or any other variations thereof, are intended to cover a non-exclusive inclusion in addition to the elements listed and may also include other elements not expressly listed.

[0020] 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.

[0021] In this article, 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 chip is called the image side of the lens.

[0022] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0023] Figure 1 A schematic structural diagram of a novel telephoto lens according to an embodiment of the present application is shown; Figure 2 A schematic diagram showing the structural dimensions of a new-structure telephoto lens according to an embodiment of the present application is shown; Figure 3 The schematic diagram of the structure of the prism in the novel structure telephoto lens according to the embodiment of the present application is shown. Figures 1 to 3 , the features, principles and other aspects of the present application are described in detail.

[0024] According to the novel structure telephoto lens of the exemplary embodiment of the present application, please also refer to Figure 1 and Figure 3, from the object side to the image side, it includes a lens assembly 100 and a prism P1 in sequence; the prism P1 includes an incident surface, a reflection surface and an exit surface, and the angle θ between the incident surface and the reflection surface of the prism P1 satisfies: 39°≤θ≤45°; the incident light passes through the lens assembly 100 along the optical axis direction of the lens assembly 100, is incident on the prism P1 from the incident surface, is reflected by the reflection surface, and is emitted from the exit surface to the imaging surface IMG of the imaging assembly. The new structure telephoto lens of this embodiment, the lens assembly 100 may include a plurality of lenses, for example 4 lenses, or other number of lenses, each lens has a corresponding optical focal length for telephoto imaging; the prism P1 not only participates in the imaging of the optical system but also realizes the folded optical path of the optical system, and the angle θ between the incident surface and the reflection surface of the prism P1 satisfies: 39°≤θ≤45°, which can be used to make the lowest point of the imaging surface IMG flush with the lowest point of the prism P1, so that the imaging assembly where the imaging surface IMG is located does not increase the lens length, and the length of the optical system is reduced by folding the optical system by the prism P1, which is conducive to reducing the lens length. Therefore, by reasonably allocating the optical focal length, thickness, spacing and refractive index of each lens of the lens assembly 100, as well as the angle and thickness of the prism P1, it is possible to achieve long-distance telephoto capability and reduce the lens length.

[0025] In an exemplary embodiment, according to the novel structure telephoto lens of the present application, Figure 2 As shown, Dmax≥4.6mm can be satisfied, wherein the maximum aperture of the lens assembly 100 is Dmax. To satisfy Dmax≥4.6mm, for example, the first lens L1 of the lens assembly 100 can be set to have a maximum aperture, and by controlling the size of the maximum aperture Dmax of the lens assembly 100, it is beneficial to achieve a large aperture effect of the lens.

[0026] In an exemplary embodiment, according to the novel structure telephoto lens of the present application, Figure 2 As shown, 0.64≤(H1+H2+H3) / f≤0.75 can be satisfied, wherein the distance from the vertex of the first lens L1 of the lens assembly 100 to the bottom point of the last lens is H1, the distance from the incident surface of the prism P1 to the bottom of the prism P1 is H2, the distance from the bottom point of the last lens of the lens assembly 100 to the incident surface of the prism P1 is H3, and the system focal length of the new structure telephoto lens is f. 0.64≤(H1+H2+H3) / f≤0.75 is satisfied, and by controlling the sum of the distance H1 from the vertex of the first lens L1 of the lens assembly 100 to the bottom point of the last lens, the distance H2 from the incident surface of the prism P1 to the bottom of the prism P1, and the distance H3 from the bottom point of the last lens of the lens assembly 100 to the incident surface of the prism P1, and the system focal length f of the new structure telephoto lens, the length of the entire optical system is reduced, and the miniaturization of the lens and the large aperture design are facilitated.

[0027] In an exemplary embodiment, according to the novel structure telephoto lens of the present application, Figure 3 As shown, 0.11≤H3 / H1≤0.15 can be satisfied, wherein the distance from the vertex of the first lens L1 of the lens assembly 100 to the bottom point of the last lens is H1, and the distance from the bottom point of the last lens of the lens assembly 100 to the incident surface of the prism P1 is H3. 0.11≤H3 / H1≤0.15 is satisfied, and by controlling the ratio range of the distance H1 from the vertex of the first lens L1 of the lens assembly 100 to the bottom point of the last lens and the distance H3 from the bottom point of the last lens of the lens assembly 100 to the incident surface of the prism P1, when the overall length of the optical system is reduced, it can be determined whether the distribution between the lenses of the lens assembly 100 is uniform, which is beneficial to reducing the sensitivity between the lenses in the lens assembly 100, and is beneficial to controlling the air gap between the lens assembly 100 and the prism P1, so as to prevent the lens assembly 100 from colliding with the prism P1 during the focusing process.

[0028] In an exemplary embodiment, according to the novel structure telephoto lens of the present application, Figure 3 As shown, 0.75≤H1 / H2≤0.9 can be satisfied, wherein the distance from the vertex of the first lens L1 of the lens assembly 100 to the bottom point of the last lens is H1, and the distance from the incident surface of the prism P1 to the bottom of the prism P1 is H2. Satisfying 0.75≤H1 / H2≤0.9 and controlling the ratio range of the distance H1 from the vertex of the first lens L1 of the lens assembly 100 to the bottom point of the last lens and the distance H2 from the incident surface of the prism P1 to the bottom of the prism P1 is beneficial to balancing the spatial distribution between the lens assembly 100 and the prism P1, and is beneficial to reducing the difficulty of subsequent processing of the optical system, and improving the yield and reliability.

[0029] In an exemplary embodiment, according to the novel structure telephoto lens of the present application, 0.92 ≤ MIC / 2*cos(90°-2*θ) / H2≤1.18 can be satisfied, wherein the imaging circle diameter of the novel structure telephoto lens is MIC, the angle between the incident surface and the reflection surface is θ, and the distance from the incident surface of prism P1 to the bottom of prism P1 is H2. 0.92 ≤ MIC / 2*cos(90°-2*θ) / H2≤1.18 is satisfied, and by controlling the imaging circle diameter MIC of the novel structure telephoto lens, the angle θ between the incident surface and the reflection surface, and the distance H2 from the incident surface of prism P1 to the bottom of prism P1, the imaging surface IMG can be moved toward the direction of lens assembly 100, which is beneficial to reducing the length of the entire optical system, and is beneficial to the miniaturization of the lens and the large aperture design.

[0030] In an exemplary embodiment, according to the novel structure telephoto lens of the present application, 0.93≤D10 / DL1≤1.24 can be satisfied, wherein the aperture of the object side surface of the first lens L1 of the lens assembly 100 is DL1, and the aperture of the incident surface of the prism P1 is D10. Satisfying 0.93≤D10 / DL1≤1.24, by controlling the ratio range of the aperture DL1 of the object side surface of the first lens L1 of the lens assembly 100 to the aperture D10 of the incident surface of the prism P1, the aperture of the incident surface of the prism P1 can be controlled within a certain range, which is conducive to reducing the size of the prism P1, and is conducive to the miniaturization and large aperture design of the lens.

[0031] In an exemplary embodiment, according to the novel structure telephoto lens of the present application, 0.54≤f1 / f≤0.96 may be satisfied, wherein the focal length of the first lens L1 of the lens assembly 100 is f1, and the system focal length of the novel structure telephoto lens is f. Satisfying 0.54≤f1 / f≤0.96, by controlling the ratio range of the focal length f1 of the first lens L1 of the lens assembly 100 and the system focal length f of the novel structure telephoto lens, the optical power of the first lens L1 of the lens assembly 100 may be controlled within a certain range, which is beneficial to the relatively small optical aberration introduced into the optical system from the very beginning, and bears the main optical power of the entire optical system, which is beneficial to the subsequent aberration correction of the optical system, which can not only improve the clarity and color accuracy of the imaging, but also indirectly improve the resolution and resolving power of the optical system.

[0032] In an exemplary embodiment, if Figure 1 As shown, according to the novel structure telephoto lens of the present application, the lens assembly 100 includes the first lens L1, the second lens L2, the third lens L3 and the fourth lens L4 in order from the object side to the image side, and the first lens L1 has a positive focal length. The first lens L1 can play a light-gathering role, which is conducive to realizing the telephoto characteristics of the lens, can reduce the size of the optical lens, realize the miniaturization of the lens, and is also conducive to realizing a large aperture design, increasing the amount of light entering, and can be used to improve the optical imaging quality and obtain high resolution. The second lens L2 to the fourth lens L4 can play a role in aberration correction. Through the reasonable allocation of the focal length, thickness and spacing of the first lens L1 to the fourth lens L4, various aberrations can be balanced to obtain clear imaging, which is conducive to the miniaturization, large aperture, telephoto and high resolution design of the lens.

[0033] In an exemplary embodiment, according to the novel structure telephoto lens of the present application, 12.5≤|V2-V1|≤33.3, 17.5≤|V4-V3|≤36.3 can be satisfied, wherein the Abbe number of the first lens L1 of the lens assembly 100 is V1, the Abbe number of the second lens L2 is V2, the Abbe number of the third lens L3 is V3, and the Abbe number of the fourth lens L4 is V4. Satisfying 12.5≤|V2-V1|≤33.3, 17.5≤|V4-V3|≤36.3, by controlling the difference range of the Abbe number V1 of the first lens L1 of the lens assembly 100 and the Abbe number V2 of the second lens L2, as well as the difference range of the Abbe number V3 of the third lens L3 of the lens assembly 100 and the Abbe number V4 of the fourth lens L4, a high and low Abbe number combination is formed, which is beneficial to the correction of high-order chromatic aberration, improves the imaging quality, makes the imaging clearer, and can improve the resolution to a certain extent, thereby improving the resolving power.

[0034] In an exemplary embodiment, according to the novel structure telephoto lens of the present application, the first lens L1 is a glass lens, and the other lenses are plastic lenses. The use of glass lenses is conducive to balancing the requirements of performance, temperature drift and color fringing. The material temperature characteristics of glass are better than those of plastic, which is conducive to improving the reliability of the lens in high temperature and high humidity environments. However, the present application does not specifically limit the material of the lens, and the material of the lens can be glass, plastic, or a mixture of glass and plastic.

[0035] In an exemplary embodiment, according to the novel structure telephoto lens of the present application, Figure 2 As shown, the reflective surface of the prism P1 is provided with a total reflection film. Thus, when the light is reflected by the reflective surface, it can be ensured that the light can be completely reflected, reducing the risk of the light being refracted out of the prism P1 when passing through the reflective surface, which helps to collect more light and improve the imaging quality.

[0036] In an exemplary embodiment, according to the novel structure telephoto lens of the present application, the material of the prism P1 can be glass, plastic, or a glass-plastic mixture.

[0037] In an exemplary embodiment, according to the novel structure telephoto lens of the present application, the novel structure telephoto lens also includes an aperture STO, which can be arranged on the object side surface of the first lens L1, or the object side surface of the second lens L2, or on the incident surface of the prism P1, or between other adjacent lenses, etc.

[0038] In an exemplary embodiment, the novel structure telephoto lens according to the present application further includes a filter IR for correcting color deviation and / or a protective glass for protecting the photosensitive element located on the imaging surface IMG. In one exemplary embodiment, according to the novel structure telephoto lens according to the present application, the filter IR may be disposed between the exit surface of the prism P1 and the imaging surface IMG, but the present invention is not limited thereto, and the filter IR may also be disposed at other positions, such as between the last lens of the lens assembly 100 and the incident surface of the prism P1, and so on.

[0039] Based on the same inventive concept, according to the camera module of the exemplary embodiment of the present application, the camera module includes the above-mentioned novel structure telephoto lens, and an imaging component arranged opposite to the exit surface of the prism P1. The implementation of the camera module can refer to the embodiment of the novel structure telephoto lens, and the repeated parts will not be repeated.

[0040] Based on the same inventive concept, according to the electronic device of the exemplary embodiment of the present application, the electronic device includes the above-mentioned camera module. The electronic device includes but is not limited to a smart phone, a tablet computer, a laptop computer, a PTZ shooting device, a surveillance camera, and other imaging devices. The implementation of the electronic device can refer to the embodiment of the camera module, and the repetitions will not be repeated.

[0041] 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 four lenses are described as an example in the embodiments, the optical imaging lens is not limited to including four lenses. If necessary, the optical imaging lens may also include other numbers of lenses.

[0042] Specific embodiments of the novel structure telephoto lens applicable to the above-mentioned embodiments are further described below with reference to the accompanying drawings.

[0043] Example 1 The following reference Figure 4 A new type of telephoto lens according to Example 1 of the present application is described.

[0044] like Figure 4 As shown, the novel structure telephoto lens includes a lens assembly 100 and a prism P1 in order from the object side to the image side. The lens assembly 100 may include a first lens L1, a second lens L2, a third lens L3 and a fourth lens L4 in order from the object side to the image side. A stop STO may be provided on the object side of the first lens L1. The prism P1 includes an incident surface, a reflection surface and an exit surface. A filter IR may be provided between the exit surface of the prism P1 and the imaging surface IMG.

[0045] The first lens L1 has positive focal power, and its object side surface is convex, and its image side surface is concave. The second lens L2 has negative focal power, and its object side surface is convex, and its image side surface is concave. The third lens L3 has negative focal power, and its object side surface is concave, and its image side surface is convex. The fourth lens L4 has positive focal power, and its object side surface is convex, and its image side surface is concave. The incident light passes through the lens assembly 100 along the optical axis direction of the lens assembly 100, enters the prism P1 from the incident area of ​​the incident surface, is reflected by the reflecting surface, is emitted from the exit surface, passes through the filter IR, and is finally imaged on the imaging surface IMG of the imaging assembly.

[0046] Table 1 shows the basic parameters of the novel structure telephoto lens of Example 1, wherein the units of the curvature radius, thickness, aperture, focal length and edge thickness are all millimeters (mm).

[0047] Table 1:

[0048] Among them, 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, Prism-R1 represents the incident surface of the prism P1, Prism-R2 represents the reflecting surface of the prism P1, Prism-R3 represents the exit surface of the prism P1, IR-R1 represents the object side surface of the filter IR, and IR-R2 represents the image side surface of the filter IR.

[0049] In Example 1, the object side surface and the image side surface of any lens among the first lens L1 to the fourth lens L4 are both even-order aspheric surfaces, the incident surface of the prism P1 is an even-order aspheric surface, and the surface shape of each aspheric lens can be defined by but not limited to the following aspheric formula: (1) Wherein, Z represents the height in the optical axis direction, c is the reciprocal of the surface radius, k is the cone coefficient, and r is the diameter in the radial direction; α represents the aspheric coefficient, α1 represents the aspheric coefficient A2, α2 represents the aspheric coefficient A4, etc. Table 2 shows the high-order coefficients A2, A4, A6, A8, A10, A12, A14, and A16 of the aspheric mirror surfaces of the second lens L2 to the fourth lens L4 that can be used in Example 1.

[0051] Table 2:

[0052] In Example 1, the system focal length f of the new structure telephoto lens is 12 mm, the equivalent focal length is 72 mm, the working band of the new structure telephoto lens is 470-650 nm, the imaging circle diameter of the new structure telephoto lens is 7.7 mm, and the field of view of the new structure telephoto lens is 33.4°. The maximum aperture Dmax of the lens assembly 100 is 4.6 mm. The distance H1 from the vertex of the first lens L1 of the lens assembly 100 to the bottom point of the last lens, the distance H2 from the incident surface of the prism P1 to the bottom of the prism P1, and the distance H3 from the bottom point of the last lens of the lens assembly 100 to the incident surface of the prism P1, the system focal length f of the new structure telephoto lens, (H1+H2+H3) / f=0.64. The distance H1 from the vertex of the first lens L1 of the lens assembly 100 to the bottom point of the last lens, and the distance H3 from the bottom point of the last lens of the lens assembly 100 to the incident surface of the prism P1, H3 / H1=0.15. The distance H1 from the vertex of the first lens L1 of the lens assembly 100 to the bottom point of the last lens, and the distance H2 from the incident surface of the prism P1 to the bottom of the prism P1, H1 / H2=0.88. The imaging circle diameter MIC of the new structure telephoto lens, the angle θ between the incident surface and the reflection surface, and the distance H2 from the incident surface of the prism P1 to the bottom of the prism P1, MIC / 2*cos(90°-2*θ) / H2=1.17. The aperture DL1 of the object side surface of the first lens L1 of the lens assembly 100, and the aperture D10 of the incident surface of the prism P1, D10 / DL1=1.24. The focal length f1 of the first lens L1 of the lens assembly 100 and the system focal length f of the novel structure telephoto lens have f1 / f=0.88. The Abbe number V1 of the first lens L1 of the lens assembly 100, the Abbe number V2 of the second lens L2, the Abbe number V3 of the third lens L3, and the Abbe number V4 of the fourth lens L4 have |V2-V1|=32.90 and |V4-V3|=17.50.

[0053] Figure 5 The MTF curve of the novel structure telephoto lens of Example 1 is shown. The MTF curve shows the transmission of image details (ie, image contrast) of different spatial frequencies by the imaging system. The MTF is close to the diffraction limit, and the effect is good. Figure 6 The relationship between the relative illumination and the field angle of the novel structure telephoto lens of Example 1 is shown. The relative illumination is greater than 75%, and the brightness of the picture is uniform. Figure 7 The field curvature diagram of the novel structure telephoto lens of Example 1 is shown. The field curvature is less than 0.06 mm and is well corrected. Figure 8 The distortion diagram of the novel structure telephoto lens of Example 1 is shown, and the distortion is less than 2%, which means the correction is very good. Fig. 9The vertical axis chromatic aberration diagram of the novel structure telephoto lens of Example 1 is shown, which illustrates the focus deviation of light rays of different wavelengths formed on the imaging plane along the direction perpendicular to the optical axis when the maximum field of view is 90Deg. The vertical axis chromatic aberration is within ±2μm and is well corrected. Figures 5 to 9 It can be seen that the new structure telephoto lens provided in Example 1 can achieve good imaging quality.

[0054] Example 2 The following reference Fig.10 A novel structure telephoto lens according to Embodiment 2 of the present application is described. In this embodiment, for the sake of brevity, some descriptions similar to Embodiment 1 are omitted.

[0055] like Fig.10 As shown, the novel structure telephoto lens includes a lens assembly 100 and a prism P1 in order from the object side to the image side. The lens assembly 100 may include a first lens L1, a second lens L2, a third lens L3 and a fourth lens L4 in order from the object side to the image side. A stop STO may be provided on the object side of the first lens L1. The prism P1 includes an incident surface, a reflection surface and an exit surface. A filter IR may be provided between the exit surface of the prism P1 and the imaging surface IMG.

[0056] The first lens L1 has positive focal power, and its object side surface is convex, and its image side surface is concave. The second lens L2 has positive focal power, and its object side surface is convex, and its image side surface is concave. The third lens L3 has negative focal power, and its object side surface is concave, and its image side surface is convex. The fourth lens L4 has positive focal power, and its object side surface is convex, and its image side surface is concave. The incident light passes through the lens assembly 100 along the optical axis direction of the lens assembly 100, enters the prism P1 from the incident area of ​​the incident surface, is reflected by the reflecting surface, is emitted from the exit surface, passes through the filter IR, and is finally imaged on the imaging surface IMG of the imaging assembly.

[0057] Table 3 shows the basic parameters of the novel structure telephoto lens of Example 2, wherein the units of the curvature radius, thickness, aperture, focal length and edge thickness are all millimeters (mm).

[0058] Table 3:

[0059] Table 4 shows the high-order coefficients A2, A4, A6, A8, A10, A12, A14 and A16 of the aspheric mirror surfaces that can be used for the second lens L2 to the fourth lens L4 in Example 2, wherein the surface shape of each aspheric surface can be defined by the formula (1) given in the above Example 1.

[0060] Table 4:

[0061] In Example 2, the system focal length f of the new structure telephoto lens is 12 mm, the equivalent focal length is 72 mm, the working band of the new structure telephoto lens is 470-650 nm, the imaging circle diameter of the new structure telephoto lens is 7.7 mm, and the field of view of the new structure telephoto lens is 33.4°. The maximum aperture Dmax of the lens assembly 100 is 4.6 mm. The distance H1 from the vertex of the first lens L1 of the lens assembly 100 to the bottom point of the last lens, the distance H2 from the incident surface of the prism P1 to the bottom of the prism P1, and the distance H3 from the bottom point of the last lens of the lens assembly 100 to the incident surface of the prism P1, the system focal length f of the new structure telephoto lens, exists (H1+H2+H3) / f=0.65. The distance H1 from the vertex of the first lens L1 of the lens assembly 100 to the bottom point of the last lens, and the distance H3 from the bottom point of the last lens of the lens assembly 100 to the incident surface of the prism P1, are H3 / H1=0.11. The distance H1 from the vertex of the first lens L1 of the lens assembly 100 to the bottom point of the last lens, and the distance H2 from the incident surface of the prism P1 to the bottom of the prism P1, are H1 / H2=0.75. The imaging circle diameter MIC of the new structure telephoto lens, the angle θ between the incident surface and the reflection surface, and the distance H2 from the incident surface of the prism P1 to the bottom of the prism P1, are MIC / 2*cos(90°-2*θ) / H2=1.18. The aperture DL1 of the object side surface of the first lens L1 of the lens assembly 100, and the aperture D10 of the incident surface of the prism P1, are D10 / DL1=1.24. The focal length f1 of the first lens L1 of the lens assembly 100 and the system focal length f of the novel structure telephoto lens have f1 / f=0.96. The Abbe number V1 of the first lens L1 of the lens assembly 100, the Abbe number V2 of the second lens L2, the Abbe number V3 of the third lens L3, and the Abbe number V4 of the fourth lens L4 have |V2-V1|=33.30 and |V4-V3|=12.20.

[0062] Fig.11 The MTF curve of the novel structure telephoto lens of Example 2 is shown. The MTF curve shows the transmission of image details (ie, image contrast) of different spatial frequencies by the imaging system. The MTF is close to the diffraction limit, and the effect is good. Fig.12 The relationship between the relative illumination and the field angle of the novel structure telephoto lens of Example 2 is shown. The relative illumination is greater than 75%, and the brightness of the picture is uniform. Fig.13 The field curvature diagram of the novel structure telephoto lens of Example 2 is shown. The field curvature is less than 0.03 mm and is well corrected. Fig.14 The distortion diagram of the novel structure telephoto lens of Example 2 is shown, and the distortion is less than 3%, which means the correction is very good. Fig.15The vertical axis chromatic aberration diagram of the novel structure telephoto lens of Example 2 is shown, which illustrates the focus deviation of light rays of different wavelengths formed on the imaging plane along the direction perpendicular to the optical axis when the maximum field of view is 90Deg. The vertical axis chromatic aberration is within ±2μm and is well corrected. Figures 11 to 15 It can be seen that the new structure telephoto lens provided in Example 2 can achieve good imaging quality.

[0063] Example 3 The following reference Fig.16 A novel structure telephoto lens according to Embodiment 3 of the present application is described. In this embodiment, for the sake of brevity, some descriptions similar to Embodiment 1 are omitted.

[0064] like Fig.16 As shown, the novel structure telephoto lens includes a lens assembly 100 and a prism P1 in order from the object side to the image side. The lens assembly 100 may include a first lens L1, a second lens L2, a third lens L3 and a fourth lens L4 in order from the object side to the image side. A stop STO may be provided on the object side of the second lens L2. The prism P1 includes an incident surface, a reflection surface and an exit surface. A filter IR may be provided between the exit surface of the prism P1 and the imaging surface IMG.

[0065] The first lens L1 has positive focal power, and its object side surface is convex, and its image side surface is convex. The second lens L2 has positive focal power, and its object side surface is convex, and its image side surface is concave. The third lens L3 has negative focal power, and its object side surface is concave, and its image side surface is convex. The fourth lens L4 has positive focal power, and its object side surface is convex, and its image side surface is convex. The incident light passes through the lens assembly 100 along the optical axis direction of the lens assembly 100, enters the prism P1 from the incident area of ​​the incident surface, is reflected by the reflecting surface, is emitted from the exit surface, passes through the filter IR, and is finally imaged on the imaging surface IMG of the imaging assembly.

[0066] Table 5 shows the basic parameters of the novel structure telephoto lens of Example 3, wherein the units of the curvature radius, thickness, aperture, focal length and edge thickness are all millimeters (mm).

[0067] Table 5:

[0068] Table 6 shows the high-order coefficients A2, A4, A6, A8, A10, A12, A14 and A16 of the aspheric mirror surfaces that can be used for the second lens L2 to the fourth lens L4 in Example 3, wherein the surface shape of each aspheric surface can be defined by the formula (1) given in the above Example 1.

[0069] Table 6:

[0070] In Example 3, the system focal length f of the new structure telephoto lens is 13.5 mm, the equivalent focal length is 72 mm, the working band of the new structure telephoto lens is 470-650 nm, the imaging circle diameter of the new structure telephoto lens is 8.5 mm, and the field of view of the new structure telephoto lens is 33.4°. The maximum aperture Dmax of the lens assembly 100 is 5.4 mm. The distance H1 from the vertex of the first lens L1 of the lens assembly 100 to the bottom point of the last lens, the distance H2 from the incident surface of the prism P1 to the bottom of the prism P1, and the distance H3 from the bottom point of the last lens of the lens assembly 100 to the incident surface of the prism P1, the system focal length f of the new structure telephoto lens, exists (H1+H2+H3) / f=0.65. The distance H1 from the vertex of the first lens L1 of the lens assembly 100 to the bottom point of the last lens, and the distance H3 from the bottom point of the last lens of the lens assembly 100 to the incident surface of the prism P1, H3 / H1=0.12. The distance H1 from the vertex of the first lens L1 of the lens assembly 100 to the bottom point of the last lens, and the distance H2 from the incident surface of the prism P1 to the bottom of the prism P1, H1 / H2=0.85. The imaging circle diameter MIC of the new structure telephoto lens, the angle θ between the incident surface and the reflection surface, and the distance H2 from the incident surface of the prism P1 to the bottom of the prism P1, MIC / 2*cos(90°-2*θ) / H2=1.09. The aperture DL1 of the object side surface of the first lens L1 of the lens assembly 100, and the aperture D10 of the incident surface of the prism P1, D10 / DL1=0.93. The focal length f1 of the first lens L1 of the lens assembly 100 and the system focal length f of the novel structure telephoto lens have f1 / f=0.59. The Abbe number V1 of the first lens L1 of the lens assembly 100, the Abbe number V2 of the second lens L2, the Abbe number V3 of the third lens L3, and the Abbe number V4 of the fourth lens L4 have |V2-V1|=12.50 and |V4-V3|=36.30.

[0071] Fig.17 The MTF curve of the novel structure telephoto lens of Example 3 is shown. The MTF curve shows the transmission of image details (ie, image contrast) of different spatial frequencies by the imaging system. The MTF is close to the diffraction limit, and the effect is good. Fig.18 The relationship between the relative illumination and the field angle of the novel structure telephoto lens of Example 3 is shown. The relative illumination is greater than 75%, and the brightness of the picture is uniform. Fig.19 The field curvature diagram of the novel structure telephoto lens of Example 3 is shown. The field curvature is less than 0.06 mm and is well corrected. Fig. 20 The distortion diagram of the novel structure telephoto lens of Example 3 is shown, and the distortion is less than 2%, which is very well corrected. Fig.21The vertical axis chromatic aberration diagram of the novel structure telephoto lens of Example 3 is shown, which illustrates the focus deviation of light rays of different wavelengths formed on the imaging plane along the direction perpendicular to the optical axis when the maximum field of view is 90Deg. The vertical axis chromatic aberration is within ±2μm and is well corrected. Figures 17 to 21 It can be seen that the new structure telephoto lens provided in Example 3 can achieve good imaging quality.

[0072] Example 4 The following reference Fig. 22 A novel structure telephoto lens according to Embodiment 4 of the present application is described. In this embodiment, for the sake of brevity, some descriptions similar to Embodiment 1 are omitted.

[0073] like Fig. 22 As shown, the novel structure telephoto lens includes a lens assembly 100 and a prism P1 in order from the object side to the image side. The lens assembly 100 may include a first lens L1, a second lens L2, a third lens L3 and a fourth lens L4 in order from the object side to the image side. A stop STO may be provided on the incident surface of the prism P1. The prism P1 includes an incident surface, a reflection surface and an exit surface. A filter IR may be provided between the exit surface of the prism P1 and the imaging surface IMG.

[0074] The first lens L1 has positive focal power, and its object side surface is convex, and its image side surface is concave. The second lens L2 has negative focal power, and its object side surface is concave, and its image side surface is concave. The third lens L3 has positive focal power, and its object side surface is convex, and its image side surface is convex. The fourth lens L4 has positive focal power, and its object side surface is convex, and its image side surface is concave. The incident light passes through the lens assembly 100 along the optical axis direction of the lens assembly 100, enters the prism P1 from the incident area of ​​the incident surface, is reflected by the reflecting surface, is emitted from the exit surface, passes through the filter IR, and is finally imaged on the imaging surface IMG of the imaging assembly.

[0075] Table 7 shows the basic parameters of the novel structure telephoto lens of Example 4, wherein the units of the curvature radius, thickness, aperture, focal length and edge thickness are all millimeters (mm).

[0076] Table 7:

[0077] Table 8 shows the high-order coefficients A2, A4, A6, A8, A10, A12, A14 and A16 of the aspheric mirror surfaces that can be used for the second lens L2 to the fourth lens L4 in Example 4, wherein the surface shape of each aspheric surface can be defined by the formula (1) given in the above Example 1.

[0078] Table 8:

[0079] In Example 4, the system focal length f of the new structure telephoto lens is 10.6 mm, the equivalent focal length is 72 mm, the working band of the new structure telephoto lens is 470-650 nm, the imaging circle diameter of the new structure telephoto lens is 6.8 mm, and the field of view of the new structure telephoto lens is 33.7°. The maximum aperture Dmax of the lens assembly 100 is 5.4 mm. The distance H1 from the vertex of the first lens L1 of the lens assembly 100 to the bottom point of the last lens, the distance H2 from the incident surface of the prism P1 to the bottom of the prism P1, and the distance H3 from the bottom point of the last lens of the lens assembly 100 to the incident surface of the prism P1, the system focal length f of the new structure telephoto lens, exists (H1+H2+H3) / f=0.75. The distance H1 from the vertex of the first lens L1 of the lens assembly 100 to the bottom point of the last lens, and the distance H3 from the bottom point of the last lens of the lens assembly 100 to the incident surface of the prism P1, H3 / H1=0.13. The distance H1 from the vertex of the first lens L1 of the lens assembly 100 to the bottom point of the last lens, and the distance H2 from the incident surface of the prism P1 to the bottom of the prism P1, H1 / H2=0.97. The imaging circle diameter MIC of the new structure telephoto lens, the angle θ between the incident surface and the reflection surface, and the distance H2 from the incident surface of the prism P1 to the bottom of the prism P1, MIC / 2*cos(90°-2*θ) / H2=0.92. The aperture DL1 of the object side surface of the first lens L1 of the lens assembly 100, and the aperture D10 of the incident surface of the prism P1, D10 / DL1=0.93. The focal length f1 of the first lens L1 of the lens assembly 100 and the system focal length f of the novel structure telephoto lens have f1 / f=0.54. The Abbe number V1 of the first lens L1 of the lens assembly 100, the Abbe number V2 of the second lens L2, the Abbe number V3 of the third lens L3, and the Abbe number V4 of the fourth lens L4 have |V2-V1|=12.50 and |V4-V3|=36.30.

[0080] Fig.23 The MTF curve of the novel structure telephoto lens of Example 4 is shown. The MTF curve shows the transmission of image details (ie, image contrast) of different spatial frequencies by the imaging system. The MTF is close to the diffraction limit, and the effect is good. Fig.24 The relationship between the relative illumination and the field angle of the novel structure telephoto lens of Example 4 is shown. The relative illumination is greater than 75%, and the brightness of the picture is uniform. Fig.25 The field curvature diagram of the novel structure telephoto lens of Example 4 is shown. The field curvature is less than 0.06 mm and is well corrected. Fig.26 The distortion diagram of the novel structure telephoto lens of Example 4 is shown, and the distortion is less than 2%, which is very well corrected. Fig. 27The vertical axis chromatic aberration diagram of the novel structure telephoto lens of Example 4 is shown, which illustrates the focus deviation of light rays of different wavelengths formed on the imaging plane along the direction perpendicular to the optical axis when the maximum field of view is 90Deg. The vertical axis chromatic aberration is within ±2μm and is well corrected. Figure 23 to Figure 27 It can be seen that the new structure telephoto lens provided in Example 4 can achieve good imaging quality.

[0081] In summary, Example 1, Example 2, Example 3 and Example 4 respectively satisfy the relationship shown in Table 9.

[0082] Table 9:

[0083] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the above features are replaced with (but not limited to) technical features with similar functions disclosed in the present application.

Claims

1. A new type of telephoto lens, characterized in that: The lens assembly and the prism are included in sequence from the object side to the image side; the prism includes an incident surface, a reflection surface and an exit surface, and the angle θ between the incident surface and the reflection surface satisfies: 39°≤θ≤45°; The incident light passes through the lens assembly along the optical axis direction of the lens assembly, enters the prism from the incident surface, is reflected by the reflection surface, and is emitted from the emission surface to the imaging surface of the imaging assembly.

2. The novel structure telephoto lens according to claim 1, characterized in that: The maximum aperture Dmax of the lens assembly satisfies: Dmax≥4.6mm.

3. The novel structure telephoto lens according to claim 1, characterized in that: The distance H1 from the vertex of the first lens of the lens assembly to the bottom point of the last lens, the distance H2 from the incident surface of the prism to the bottom of the prism, the distance H3 from the bottom point of the last lens of the lens assembly to the incident surface of the prism, and the system focal length f of the novel structure telephoto lens satisfy: 0.64≤(H1+H2+H3) / f≤0.

75.

4. The novel structure telephoto lens according to claim 1, characterized in that: A distance H1 from the vertex of the first lens of the lens assembly to the bottom point of the last lens, and a distance H3 from the bottom point of the last lens of the lens assembly to the incident surface of the prism satisfy: 0.11≤H3 / H1≤0.

15.

5. The novel structure telephoto lens according to claim 1, characterized in that: The distance H1 from the vertex of the first lens of the lens assembly to the bottom point of the last lens, and the distance H2 from the incident surface of the prism to the bottom of the prism, satisfy: 0.75≤H1 / H2≤0.

9.

6. The novel structure telephoto lens according to claim 1, characterized in that: The imaging circle diameter MIC of the novel structure telephoto lens, the angle θ between the incident surface and the reflecting surface, and the distance H2 from the incident surface of the prism to the bottom of the prism satisfy: 0.92 ≤ MIC / 2*cos(90°-2*θ) / H2≤1.

18.

7. The novel structure telephoto lens according to claim 1, characterized in that: The aperture DL1 of the object side surface of the first lens of the lens assembly and the aperture D10 of the incident surface of the prism satisfy: 0.93≤D10 / DL1≤1.

24.

8. The novel structure telephoto lens according to claim 1, characterized in that: The focal length f1 of the first lens of the lens assembly and the system focal length f of the novel structure telephoto lens satisfy: 0.54≤f1 / f≤0.

96.

9. The novel structure telephoto lens according to claim 1, characterized in that: The Abbe number V1 of the first lens of the lens assembly, the Abbe number V2 of the second lens of the lens assembly, the Abbe number V3 of the third lens of the lens assembly, and the Abbe number V4 of the fourth lens of the lens assembly satisfy: 12.5≤|V2-V1|≤33.3, 17.5≤|V4-V3|≤36.

3.

10. A camera module, characterized in that: The camera module includes a novel structure telephoto lens as described in any one of claims 1 to 9, and the imaging component arranged opposite to the exit surface of the prism.

Images