A wide-angle optical imaging system for unmanned aerial vehicles

Abstract

The utility model relates to optical system technical field, concretely relates to a kind of unmanned aerial vehicle wide-angle optical imaging system, including the first lens, diaphragm, second lens, third lens, fourth lens and fifth lens arranged in order from object side to image side;The first lens has negative refractive power, its object side is convex at near axis, its image side is concave at near optical axis;The second lens has negative refractive power, its object side is concave;The third lens has positive refractive power, its image side is convex;The fourth lens has positive refractive power, its object side is convex at near axis, its image side is convex at near axis;The fifth lens, has negative refractive power, its object side is concave at near axis.The utility model's unmanned aerial vehicle wide-angle optical imaging system adopts five lens structure, with the optimized combination of glass lens and plastic lens, can satisfy the shooting lens needs of unmanned aerial vehicle, give consideration to high imaging quality, lightweight and low cost requirement.

Description

Technical Field

[0001] This utility model relates to the field of optical system technology, specifically to a wide-angle optical imaging system for unmanned aerial vehicles (UAVs). Background Technology

[0002] With the rapid development of optical imaging technology, cameras are now widely used in security, surveillance, vehicle cameras and drones.

[0003] Currently, various electronic devices equipped with cameras are increasingly moving towards miniaturization. For example, drone lenses need to balance high image quality, lightweight design, and low cost. Traditional lenses often use an all-glass lens design, which, while offering high image quality, results in greater weight, impacting the drone's battery life. On the other hand, while all-plastic lenses are lightweight, they are prone to deformation in high-temperature or high-humidity environments, affecting image stability. Therefore, a hybrid lens design that combines the advantages of both glass and plastic materials is needed. Summary of the Invention

[0004] In order to overcome the shortcomings and deficiencies of the existing technology, the purpose of this utility model is to provide a wide-angle optical imaging system for drones, which adopts a five-lens structure and an optimized combination of glass lenses and plastic lenses, so as to meet the requirements of drone shooting lenses to take into account high imaging quality, lightweight and low cost.

[0005] The objective of this utility model is achieved through the following technical solution: a wide-angle optical imaging system for unmanned aerial vehicles, comprising a first lens, an aperture stop, a second lens, a third lens, a fourth lens, and a fifth lens arranged sequentially from the object side to the image side;

[0006] The first and third lenses are spherical, while the second, third, and fifth lenses are all aspherical.

[0007] The first lens has negative refractive power, its object side is convex near the axis, and its image side is concave near the optical axis;

[0008] The second lens has negative refractive power, and its object-side surface is concave.

[0009] The third lens has positive refractive power, and its image-side surface is convex.

[0010] The fourth lens has positive refractive power, and its object side is convex near the axis, and its image side is convex near the axis.

[0011] The fifth lens has negative refractive power, and its object-side surface is concave near the axis.

[0012] The UAV wide-angle optical imaging system meets the following conditions:

[0013] 3.61 < TTL / f < 4.23;

[0014] -0.63 < SAG32 / CT3 < -0.32;

[0015] Wherein, TTL is the distance from the object side of the first lens to the imaging surface on the optical axis, f is the focal length of the optical imaging system, SAG32 is the horizontal displacement distance from the intersection of the image side of the third lens and the optical axis to the position of the maximum effective radius of the image side of the third lens on the optical axis, and CT3 is the thickness of the third lens on the optical axis.

[0016] Furthermore, the UAV wide-angle optical imaging system also satisfies the following conditions:

[0017] 0.28 <L1 / L2<0.42;

[0018] Wherein, L1 is the distance on the optical axis from the aperture to the image side of the second lens, and L2 is the distance on the optical axis from the aperture to the image side of the third lens.

[0019] Furthermore, the UAV wide-angle optical imaging system also satisfies the following conditions:

[0020] 1.21 <TTL / ImgH<1.53;

[0021] Where TTL is the distance on the optical axis from the side of the first lens to the imaging surface, and ImgH is the maximum imaging height of the optical imaging system.

[0022] Furthermore, the UAV wide-angle optical imaging system also satisfies the following conditions:

[0023] 0.13 <CT1 / CT2≤1.78;

[0024] Wherein, CT1 is the thickness of the first lens on the optical axis, and CT2 is the thickness of the second lens on the optical axis.

[0025] Furthermore, the UAV wide-angle optical imaging system also satisfies the following conditions:

[0026] 0.62 <Yc42 / f<0.85;

[0027] Where Yc42 is the vertical distance from the inflection point on the image side of the fourth lens, which is the closest horizontal distance to the imaging plane, to the optical axis, and f is the focal length of the optical imaging system.

[0028] Furthermore, the UAV wide-angle optical imaging system also satisfies the following conditions:

[0029] 0.01 <T34 / AAT<0.06;

[0030] Where T34 is the air gap on the optical axis from the image side of the third lens to the object side of the fourth lens, and AAT is the sum of the air gaps between each adjacent lens from the first lens to the third lens.

[0031] Furthermore, the UAV wide-angle optical imaging system also satisfies the following conditions:

[0032] -11.35 <f / (f1+f3)<-10.39;

[0033] Where f is the focal length of the optical imaging system, f1 is the focal length of the first lens, and f3 is the focal length of the third lens.

[0034] Furthermore, the UAV wide-angle optical imaging system also satisfies the following conditions:

[0035] 0.24 <f / f45<0.56;

[0036] Where f is the focal length of the optical imaging system, and f45 is the combined focal length of the fourth and fifth lenses.

[0037] Furthermore, the UAV wide-angle optical imaging system also satisfies the following conditions:

[0038] 1.95 <f / CT3<3.56;

[0039] Where f is the focal length of the optical imaging system, and CT3 is the thickness of the third lens on the optical axis.

[0040] The beneficial effects of this invention are as follows: This UAV wide-angle optical imaging system adopts a five-lens structure, using an optimized combination of glass and plastic lenses. By rationally configuring the refractive power and surface shape of the first, second, third, fourth, and fifth lenses, and ensuring the UAV wide-angle optical imaging system meets specific conditions, the optical length of the UAV wide-angle optical imaging system can be shortened, achieving high resolution, low distortion, and joint color reproduction. The use of plastic lenses significantly reduces the weight of the lens, which helps extend the UAV's flight time. Furthermore, the manufacturing cost of plastic lenses is lower, while the use of glass lenses ensures key optical performance and improves the lens's stability in high-temperature and high-humidity environments. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of a wide-angle optical imaging system for a drone according to Embodiment 1 of this utility model;

[0042] Figure 2 This is a field curvature and distortion curve diagram of a wide-angle optical imaging system for a drone according to Embodiment 1 of this utility model;

[0043] Figure 3 This is an axial aberration curve diagram of a wide-angle optical imaging system for a drone according to Embodiment 1 of this utility model;

[0044] Figure 4 This is a schematic diagram of a wide-angle optical imaging system for a drone according to Embodiment 2 of this utility model;

[0045] Figure 5 This is a field curvature and distortion curve diagram of a wide-angle optical imaging system for a drone according to Embodiment 2 of this utility model;

[0046] Figure 6 This is an axial aberration curve diagram of a wide-angle optical imaging system for a drone according to Embodiment 2 of this utility model;

[0047] Figure 7 This is a schematic diagram of a wide-angle optical imaging system for a drone according to Embodiment 3 of this utility model;

[0048] Figure 8 This is a field curvature and distortion curve diagram of a wide-angle optical imaging system for a drone according to Embodiment 3 of this utility model;

[0049] Figure 9 This is an axial aberration curve of a wide-angle optical imaging system for a drone according to Embodiment 3 of this utility model.

[0050] The reference numerals in the attached diagram are as follows: E1 - first lens, STO - aperture stop, E2 - second lens, E3 - third lens, E4 - fourth lens, E5 - fifth lens, E6 - infrared filter, S1 - object-side surface of the first lens, S2 - image-side surface of the first lens, S3 - object-side surface of the second lens, S4 - image-side surface of the second lens, S5 - object-side surface of the third lens, S6 - image-side surface of the third lens, S7 - object-side surface of the fourth lens, S8 - image-side surface of the fourth lens, S9 - object-side surface of the fifth lens, S10 - image-side surface of the fifth lens, S11 - imaging plane. Detailed Implementation

[0051] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to embodiments and accompanying drawings. The content mentioned in the embodiments is not intended to limit the present invention.

[0052] It should be noted that when a component is referred to as "fixed to" or "set on" another component, it can be directly on the other component or indirectly on that other component.

[0053] When a component is said to be "connected to" another component, it can be directly connected to the other component or indirectly connected to that other component.

[0054] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0055] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature.

[0056] In the description of this application, "multiple" means two or more, unless otherwise expressly and specifically defined.

[0057] A wide-angle optical imaging system for unmanned aerial vehicles includes a first lens E1, an aperture stop STO, a second lens E2, a third lens E3, a fourth lens E4, and a fifth lens E5 arranged sequentially from the object side to the image side;

[0058] The first lens E1 and the third lens E3 are spherical, while the second lens E2, the third lens E3 and the fifth lens E5 are all aspherical.

[0059] The first lens E1 has negative refractive power, its object side S1 is convex near the axis, and its image side S2 is concave near the optical axis.

[0060] The second lens E2 has negative refractive power, and its object-side surface S3 is concave.

[0061] The third lens E3 has positive refractive power, and its image-side surface S6 is convex.

[0062] The fourth lens E4 has positive refractive power, its object side S7 is convex at the paraxial position, and its image side S8 is convex at the paraxial position.

[0063] The fifth lens E5 has negative refractive power, and its object-side surface S9 is concave near the axis.

[0064] The wide-angle optical imaging system of this UAV also includes an infrared filter E6, which is placed between the fifth lens E5 and the imaging surface S11. The infrared filter E6 filters out infrared light entering the lens to avoid the imaging effect being affected by infrared light.

[0065] The wide-angle optical imaging system for unmanned aerial vehicles described in this utility model meets the following conditions:

[0066] 3.61 < TTL / f < 4.23;

[0067] -0.63 < SAG32 / CT3 < -0.32;

[0068] Wherein, TTL is the distance on the optical axis from the object side of the first lens E1 to the imaging surface S11, f is the focal length of the optical imaging system, SAG32 is the horizontal displacement distance on the optical axis from the intersection of the image side of the third lens E3 and the optical axis to the position of the maximum effective radius of the image side of the third lens E3, and CT3 is the thickness of the third lens E3 on the optical axis. Limiting the TTL / f ratio within the above range can avoid excessive system length and ensure effective correction of aberrations through reasonable lens layout; limiting the SAG32 / CT3 ratio within the above range can optimize the lens's ability to correct aberrations such as spherical aberration and astigmatism, and avoid excessive bending that leads to uncontrollable optical path distortion.

[0069] Furthermore, the UAV wide-angle optical imaging system also satisfies the following conditions:

[0070] 0.28 <L1 / L2<0.42;

[0071] Wherein, L1 is the distance on the optical axis from the aperture stop STO to the image-side surface of the second lens E2, and L2 is the distance on the optical axis from the aperture stop STO to the image-side surface of the third lens E3. Limiting the L1 / L2 ratio to the above range can effectively correct aberrations such as distortion and field curvature caused by a large field of view, while also suppressing vignetting, improving edge imaging quality, balancing system compactness and optical performance, optimizing the light path, and ensuring efficient light transmission.

[0072] Furthermore, the UAV wide-angle optical imaging system also satisfies the following conditions:

[0073] 1.21 <TTL / ImgH<1.53;

[0074] Where TTL is the distance on the optical axis from the object side of the first lens E1 to the imaging surface S11, and ImgH is the maximum imaging height of the optical imaging system. By limiting the TTL / ImgH ratio to the above range, a comprehensive optimization of the wide-angle optical system can be achieved in terms of compactness, field of view coverage, aberration correction, and imaging quality, meeting the current demand of UAVs for high-performance miniaturized lenses.

[0075] Furthermore, the UAV wide-angle optical imaging system also satisfies the following conditions:

[0076] 0.13 <CT1 / CT2≤1.78;

[0077] Wherein, CT1 is the thickness of the first lens E1 on the optical axis, and CT2 is the thickness of the second lens E2 on the optical axis. By limiting the CT1 / CT2 ratio to the above range, aberration correction, system size, structural stability, and manufacturing process can be balanced, ultimately improving the imaging quality, reliability, and practicality of the wide-angle system.

[0078] Furthermore, the UAV wide-angle optical imaging system also satisfies the following conditions:

[0079] 0.62 <Yc42 / f<0.85;

[0080] Where Yc42 is the vertical distance from the inflection point on the image side of the fourth lens E4, which is the closest horizontal distance to the imaging plane S11, to the optical axis, and f is the focal length of the optical imaging system. By limiting the Yc42 / f ratio to the above range, the position of the inflection point can be optimized, balancing the aberration correction, structural compactness, and imaging uniformity of the wide-angle system. This is a key design constraint for achieving high-quality wide-angle imaging.

[0081] Furthermore, the UAV wide-angle optical imaging system also satisfies the following conditions:

[0082] 0.01 <T34 / AAT<0.06;

[0083] Where T34 is the air gap on the optical axis from the image side of the third lens E3 to the object side of the fourth lens E4, and AAT is the sum of the air gaps between each adjacent lens from the first lens E1 to the third lens E3. By constraining the T34 / AAT ratio, the wide-angle optical system achieves a balance between aberration correction, compactness, optical path design, manufacturing feasibility, and back focus matching, ultimately realizing a high-performance, small-volume wide-angle imaging effect.

[0084] Furthermore, the UAV wide-angle optical imaging system also satisfies the following conditions:

[0085] -11.35 <f / (f1+f3)<-10.39;

[0086] Where f is the focal length of the optical imaging system, f1 is the focal length of the first lens E1, and f3 is the focal length of the third lens E3. Limiting the f / (f1+f3) ratio within the above range can coordinate the distribution of optical power, field of view expansion, aberration correction, and system compactness, ensuring that the wide-angle optical system can maintain high imaging quality and a reasonable physical structure even in a wide field of view.

[0087] Furthermore, the UAV wide-angle optical imaging system also satisfies the following conditions:

[0088] 0.24 <f / f45<0.56;

[0089] Where f is the focal length of the optical imaging system, and f45 is the combined focal length of the fourth lens E4 and the fifth lens E5. By limiting the f / f45 ratio to the above range and optimizing the optical power distribution of the fourth lens E4 and the fifth lens E5 group, efficient aberration correction, compact system structure, and balanced optical performance are achieved under wide-angle conditions.

[0090] Furthermore, the UAV wide-angle optical imaging system also satisfies the following conditions:

[0091] 1.95 <f / CT3<3.56;

[0092] Where f is the focal length of the optical imaging system, and CT3 is the thickness of the third lens E3 on the optical axis. Limiting the f / CT3 ratio within the above range can balance aberration correction, system compactness, manufacturing feasibility, and structural stability, ensuring that the wide-angle optical system can still achieve high-resolution, low-distortion imaging performance in a wide field of view, while also taking into account mass production economy and reliability.

[0093] 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.

[0094] Example 1

[0095] See Figure 1-3 A wide-angle optical imaging system for unmanned aerial vehicles includes a first lens E1, an aperture stop STO, a second lens E2, a third lens E3, a fourth lens E4, and a fifth lens E5 arranged sequentially from the object side to the image side.

[0096] The first lens E1 and the third lens E3 are spherical, while the second lens E2, the third lens E3 and the fifth lens E5 are all aspherical.

[0097] The first lens E1 has negative refractive power, its object side S1 is convex near the axis, and its image side S2 is concave near the optical axis.

[0098] The second lens E2 has negative refractive power, and its object-side surface S3 is concave.

[0099] The third lens E3 has positive refractive power, and its image-side surface S6 is convex.

[0100] The fourth lens E4 has positive refractive power, its object side S7 is convex at the paraxial position, and its image side S8 is convex at the paraxial position.

[0101] The fifth lens E5 has negative refractive power, and its object-side surface S9 is concave near the axis.

[0102] The wide-angle optical imaging system of this UAV also includes an infrared filter E6, which is placed between the fifth lens E5 and the imaging surface S11. The infrared filter E6 filters out infrared light entering the lens to avoid the imaging effect being affected by infrared light.

[0103] Please refer to Table 1-1 and Table 1-2 below.

[0104]

[0105]

[0106]

[0107]

[0108] Table 1-1 shows the detailed structural data for Example 1, where the units for radius of curvature, thickness, and focal length are millimeters, f is the focal length of the UAV wide-angle optical imaging system, and Fno is the relative aperture of the UAV wide-angle optical imaging system. FOV In a wide-angle optical imaging system for unmanned aerial vehicles (UAVs), the field of view is represented by the angle of view, which determines the width of the scene that the imaging system can observe.

[0109] Table 1-2 shows the aspheric coefficient data in Example 1, where k represents the conical coefficient in the aspheric curve equation, and A4, A6, A8, A10, A12, A14 and A16 represent the 4th, 6th, 8th, 10th, 12th, 14th and 16th order aspheric coefficients of each surface.

[0110] In addition, the tables in the following embodiments are schematic diagrams and graphs corresponding to each embodiment. The definitions of the data in the tables are the same as those in Tables 1-1 and 1-2 of the first embodiment, and will not be repeated here.

[0111] Example 2

[0112] See Figure 4-6 A wide-angle optical imaging system for unmanned aerial vehicles includes a first lens E1, an aperture stop STO, a second lens E2, a third lens E3, a fourth lens E4, and a fifth lens E5 arranged sequentially from the object side to the image side.

[0113] The first lens E1 and the third lens E3 are spherical, while the second lens E2, the third lens E3 and the fifth lens E5 are all aspherical.

[0114] The first lens E1 has negative refractive power, its object side S1 is convex near the axis, and its image side S2 is concave near the optical axis.

[0115] The second lens E2 has negative refractive power, and its object-side surface S3 is concave.

[0116] The third lens E3 has positive refractive power, and its image-side surface S6 is convex.

[0117] The fourth lens E4 has positive refractive power, its object side S7 is convex at the paraxial position, and its image side S8 is convex at the paraxial position.

[0118] The fifth lens E5 has negative refractive power, and its object-side surface S9 is concave near the axis.

[0119] The wide-angle optical imaging system of this UAV also includes an infrared filter E6, which is placed between the fifth lens E5 and the imaging surface S11. The infrared filter E6 filters out infrared light entering the lens to avoid the imaging effect being affected by infrared light.

[0120] Please refer to Table 2-1 and Table 2-2 below.

[0121]

[0122]

[0123]

[0124]

[0125]

[0126] Example 3

[0127] See Figure 7-9 A wide-angle optical imaging system for unmanned aerial vehicles includes a first lens E1, an aperture stop STO, a second lens E2, a third lens E3, a fourth lens E4, and a fifth lens E5 arranged sequentially from the object side to the image side.

[0128] The first lens E1 and the third lens E3 are spherical, while the second lens E2, the third lens E3 and the fifth lens E5 are all aspherical.

[0129] The first lens E1 has negative refractive power, its object side S1 is convex near the axis, and its image side S2 is concave near the optical axis.

[0130] The second lens E2 has negative refractive power, and its object-side surface S3 is concave.

[0131] The third lens E3 has positive refractive power, and its image-side surface S6 is convex.

[0132] The fourth lens E4 has positive refractive power, its object side S7 is convex at the paraxial position, and its image side S8 is convex at the paraxial position.

[0133] The fifth lens E5 has negative refractive power, and its object-side surface S9 is concave near the axis.

[0134] The wide-angle optical imaging system of this UAV also includes an infrared filter E6, which is placed between the fifth lens E5 and the imaging surface S11. The infrared filter E6 filters out infrared light entering the lens to avoid the imaging effect being affected by infrared light.

[0135] Please refer to Table 3-1 and Table 3-2 below.

[0136]

[0137]

[0138]

[0139]

[0140] Example 4

[0141] Based on the foregoing embodiments, this utility model provides an electronic device, including the wide-angle optical imaging system for unmanned aerial vehicles provided in any of the above embodiments.

[0142] The above embodiments are preferred implementations of this utility model. In addition, this utility model can also be implemented in other ways. Any obvious substitutions without departing from the concept of this utility model are within the protection scope of this utility model.

Claims

1. A wide-angle optical imaging system for unmanned aerial vehicles, characterized by: The first lens, the diaphragm, the second lens, the third lens, the fourth lens and the fifth lens are sequentially arranged from the object side to the image side; The first lens and the third lens are spherical surfaces, and the second lens, the third lens and the fifth lens are aspherical surfaces; The first lens has a negative refractive power, and the object side surface thereof is a convex surface at the near axis, and the image side surface thereof is a concave surface at the near optical axis; The second lens has a negative refractive power, and the object side surface thereof is a concave surface; The third lens has a positive refractive power, and the image side surface thereof is a convex surface; The fourth lens has a positive refractive power, and the object side surface thereof is a convex surface at the near axis, and the image side surface thereof is a convex surface at the near axis; The fifth lens has a negative refractive power, and the object side surface thereof is a concave surface at the near axis; The wide-angle optical imaging system of the unmanned aerial vehicle satisfies the following conditions: 3.61 < TTL / f < 4.23; -0.63 < SAG32 / CT3 < -0.32; Wherein, TTL is the distance from the object side surface of the first lens to the imaging surface on the optical axis, f is the focal length of the optical imaging system, SAG32 is the horizontal displacement distance of the intersection of the image side surface of the third lens and the optical axis to the position of the maximum effective radius of the image side surface of the third lens on the optical axis, and CT3 is the thickness of the third lens on the optical axis. 2.The wide-angle optical imaging system of a UAV according to claim 1, wherein: Also satisfy the following conditions: 0.28 < L1 / L2 < 0.42; Wherein, L1 is the distance from the diaphragm to the image side surface of the second lens on the optical axis, and L2 is the distance from the diaphragm to the image side surface of the third lens on the optical axis. 3.The wide-angle optical imaging system of a UAV according to claim 1, wherein: Also satisfy the following conditions: 1.21 < TTL / ImgH < 1.53; Wherein, TTL is the distance from the object side surface of the first lens to the imaging surface on the optical axis, and ImgH is the maximum imaging height of the optical imaging system. 4.The wide-angle optical imaging system of a UAV according to claim 1, wherein: Also satisfy the following conditions: 0.13 < CT1 / CT2 < 1.78; Wherein, CT1 is the thickness of the first lens on the optical axis, and CT2 is the thickness of the second lens on the optical axis.

5. The wide-angle optical imaging system of claim 1, wherein: Also satisfy the following conditions: 0.62 < Yc42 / f < 0.85; Wherein, Yc42 is the vertical distance from the inflection point on the image side surface of the fourth lens to the optical axis, and f is the focal length of the optical imaging system.

6. The wide-angle optical imaging system of claim 1, wherein: Also satisfy the following conditions: 0.01 < T34 / AAT < 0.06; Wherein, T34 is the air gap from the image side surface of the third lens to the object side surface of the fourth lens on the optical axis, and AAT is the sum of the air gaps between each adjacent lens from the first lens to the third lens.

7. The wide-angle optical imaging system of claim 1, wherein: Also satisfy the following conditions: -11.35 < f / (f1+f3) < -10.39; Wherein, f is the focal length of the optical imaging system, f1 is the focal length of the first lens, and f3 is the focal length of the third lens.

8. The wide-angle optical imaging system of claim 1, wherein: Also satisfy the following conditions: 0.24 < f / f45 < 0.56; Wherein, f is the focal length of the optical imaging system, and f45 is the combined focal length of the fourth lens and the fifth lens.

9. The wide-angle optical imaging system of claim 1, wherein: Also satisfy the following conditions: 1.95 < f / CT3 < 3.56; Wherein, f is the focal length of the optical imaging system, and CT3 is the thickness of the third lens on the optical axis.

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