Wide-angle unmanned aerial vehicle lens

Abstract

This invention relates to the field of optical imaging technology and provides a wide-angle drone lens. The wide-angle drone lens includes a first lens, a second lens, a third lens, and a fourth lens arranged sequentially along the optical axis from the object plane to the image plane. The first lens is a meniscus negative diopter lens with its convex surface facing the object plane. The second lens is a meniscus positive diopter lens with its convex surface facing the object plane. The third lens has two even-order aspherical lenses on both sides. The fourth lens is a biconvex positive diopter lens. The wide-angle drone lens provided by this invention is not only simple in structure, lightweight, and low in cost, but also capable of imaging at infinity. When applied to drone aerial photography, it can meet the increasingly high imaging quality requirements of users and effectively ensure that the drone has a long endurance.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of optical imaging technology, and particularly relates to a wide-angle unmanned aerial vehicle lens. BACKGROUND

[0002] With the wide application of unmanned aerial vehicle aerial photography, users have higher and higher requirements on the imaging quality of aerial photography. In order to ensure that the unmanned aerial vehicle has a long endurance, the weight of the imaging lens is required to be lighter and lighter, and the imaging lens is also constantly innovated. It is the development trend of the entire unmanned aerial vehicle industry to design a lens with simple structure and light weight. SUMMARY

[0003] The purpose of the embodiment of the present application is to provide a wide-angle unmanned aerial vehicle lens, aiming to solve the demand of high imaging quality and high endurance of the existing unmanned aerial vehicle.

[0004] The embodiment of the present application is implemented as follows: a wide-angle unmanned aerial vehicle lens, the wide-angle unmanned aerial vehicle lens comprising: a first lens, a second lens, a third lens and a fourth lens arranged in sequence along an optical axis from an object plane to an image plane; the first lens is a meniscus negative power lens, the convex surface faces the object plane; the second lens is a meniscus positive power lens, the convex surface faces the object plane; the third lens is a double-surface even aspheric lens; the fourth lens is a double-convex positive power lens.

[0005] Further, an aperture is arranged between the second lens and the third lens.

[0006] Further, the distance between the first lens and the second lens is Z, and Z [10.01, 10.21].

[0007] Further, the distance Z between the first lens and the second lens is 10.11 mm.

[0008] Further, the first lens and the fourth lens satisfy the following conditions:

[0009] -1.5 < f1 / f4 < 0;

[0010] Wherein, f1 is the effective focal length of the first lens, and f4 is the effective focal length of the fourth lens.

[0011] Further, the refractive index of the third lens is set as n3, and the Abbe number is set as V3, satisfying the following conditional expression:

[0012] 1.83 < n3 < 2.1;

[0013] 18 < V3 < 25.

[0014] Furthermore, the wide-angle drone lens also includes a lens barrel, and the first lens, the second lens, the third lens and the fourth lens are disposed inside the lens barrel.

[0015] Furthermore, an aperture adjustment ring is rotatably connected to the lens barrel, and the aperture adjustment ring is coupled to the aperture to adjust the amount of light transmitted through the aperture.

[0016] Furthermore, a focusing adjustment ring is rotatably connected to the lens barrel, and the focusing adjustment ring is coupled to the first lens or the second lens to adjust the distance between the first lens and the second lens.

[0017] Compared with existing technologies, the wide-angle drone lens given in the above embodiments has the advantages of simple structure, low cost and light weight, while taking into account both image quality and battery life; the working wavelength of the wide-angle drone lens is visible light, which can image at infinite distance; it is particularly suitable for drone surveying scenarios; in addition, the lenses used in each lens can be made of domestic optical glass, which can greatly reduce the lens manufacturing cost and usage cost. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a wide-angle drone lens provided in an embodiment of the present invention.

[0019] Figure 2 This is a schematic diagram of light propagation in a wide-angle drone lens according to an embodiment of the present invention.

[0020] Figure 3 This is a schematic diagram of the MTF of a wide-angle drone lens in an embodiment of the present invention.

[0021] Figure 4 This is a schematic diagram of field curvature and distortion of a wide-angle drone lens in an embodiment of the present invention.

[0022] Figure 5 This is a dot matrix diagram of the wide-angle drone lens in an embodiment of the present invention.

[0023] Figure 6 This is a diagram showing the relevant parameters of each lens in an embodiment of the present invention.

[0024] In the attached diagram: 1-first lens, 2-second lens, 3-third lens, 4-fourth lens, 5-aperture, IMG-image plane. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0026] The specific implementation of the present invention will be described in detail below with reference to specific embodiments.

[0027] Figure 1 This is a schematic diagram of the structure of a wide-angle drone lens provided in an embodiment of the present invention; Figure 1 This is a schematic diagram of the structure of a wide-angle drone lens provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of light propagation in a wide-angle drone lens according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the MTF (Modulation Transfer Function) of the wide-angle drone lens in an embodiment of the present invention; Figure 4 This is a schematic diagram of field curvature and distortion of a wide-angle drone lens in an embodiment of the present invention; Figure 5 This is a dot matrix diagram of the wide-angle drone lens in an embodiment of the present invention; Figure 6 The following diagram illustrates the relevant parameter markings for each lens in this embodiment of the invention. The wide-angle drone lens includes: a first lens 1, a second lens 2, a third lens 3, and a fourth lens 4 arranged sequentially along the optical axis from the object plane to the image plane (IMG); the first lens 1 is a meniscus negative diopter lens with its convex surface facing the object plane; the second lens 2 is a meniscus positive diopter lens with its convex surface facing the object plane; the third lens 3 has two even-order aspherical lenses; and the fourth lens 4 is a biconvex positive diopter lens.

[0028] The wide-angle drone lens of this embodiment has the advantages of simple structure, low cost, and light weight. The working wavelength of this wide-angle drone lens is visible light, which can image at infinite distances. It is particularly suitable for drone surveying scenarios. In addition, the lenses used in each lens can be made of domestic optical glass, which can greatly reduce the lens manufacturing and usage costs. It effectively expands the application scenarios of drone surveying, not only making the structure simple and easy to manufacture, but also improving the long-distance imaging effect, saving manufacturing costs, and facilitating its widespread application.

[0029] The aforementioned optical axis is not a solid line with a physical object, but rather a reference line in an optical sense, that is... Figure 1 The center lines of the first lens 1, the second lens 2, the third lens 3, and the fourth lens 4 (not shown in the figure). (By...) Figure 1 As can be easily seen, the angle between the object plane and the optical axis of the lens can be adjusted arbitrarily between 45° and 90°. The image plane IMG is located at a certain distance to the right of the fourth lens 4. The image plane IMG is actually the photosensitive surface of the image sensor in the camera.

[0030] In one example of this embodiment, an aperture 5 is provided between the second lens 2 and the third lens 3. The amount of light entering the wide-angle drone lens can be adjusted through the aperture 5, thereby improving the imaging effect according to different mapping backgrounds.

[0031] In one example of this embodiment, the first lens 1 and the second lens 2 form the front lens group, and the third lens 3 and the fourth lens 4 form the rear lens group; the focal points of the front lens group and the rear lens group coincide at the center of the aperture 5 (also called the aperture stop). Thus, the aperture 5 can be used to adjust the spot size of the wide-angle drone lens (hereinafter referred to as the lens), control the amount of light entering, and the imaging position on the image plane IMG, etc.

[0032] In one embodiment, the wide-angle drone lens further includes a lens barrel, in which the first lens 1, the second lens 2, the third lens 3, and the fourth lens 4 are disposed.

[0033] In one example of this embodiment, an aperture adjustment ring is rotatably connected to the lens barrel. The aperture adjustment ring is coupled to the aperture and is used to adjust the amount of light transmitted through the aperture.

[0034] In this example, the coupling between the aperture adjustment ring and the aperture can be achieved through the meshing connection between the gear and the external gear ring, or through the meshing connection between the worm gear and the worm. This example is not limited to these.

[0035] In one embodiment, the technical specifications of the wide-angle drone lens are as follows: focal length: f = 16mm; shooting distance: infinity; average distortion: = 5%; aperture F = 5.6; maximum field of view 2ω: 85.6°; total optical length ∑ = 38.6mm;

[0036] Applicable spectral range: visible light.

[0037] Combination Figure 6 The relevant parameters of the first lens 1, the second lens 2, the third lens 3 and the fourth lens 4 are shown in Table 1 below;

[0038] Table 1 shows the relevant parameters for each lens.

[0039]

[0040] In one embodiment, the third lens 3 is an even-order aspherical lens on both sides, and the parameters of the even-order aspherical lens can be referred to in Table 2 below;

[0041] Table 2 shows the parameters of even-order aspherical lenses.

[0042]

[0043] In the example of this embodiment, the wide-angle drone lens can be a component / accessory of a drone, optical inspection equipment, camera equipment, or photography equipment, or it can be a component of an independent surveying camera. It can be modularly installed with the drone for convenience and speed; however, it is not specifically limited to this.

[0044] like Figure 2 As shown, in one embodiment, the distance between the first lens 1 and the second lens 2 is Z, where Z ∈ [10.01, 10.21].

[0045] In one example of this embodiment, the distance Z between the first lens 1 and the second lens 2 is 10.01 mm.

[0046] In one example of this embodiment, the distance Z between the first lens 1 and the second lens 2 is 10.05 mm.

[0047] In one example of this embodiment, the distance Z between the first lens 1 and the second lens 2 is 10.15 mm.

[0048] In one example of this embodiment, the distance Z between the first lens 1 and the second lens 2 is 10.21 mm.

[0049] In one example of this embodiment, the distance Z between the first lens 1 and the second lens 2 is 10.11 mm.

[0050] In one embodiment, the first lens 1 and the fourth lens 4 satisfy the following condition:

[0051] -1.5 < f1 / f4 < 0;

[0052] Where f1 is the effective focal length of the first lens 1 and f4 is the effective focal length of the fourth lens 4.

[0053] In one embodiment, a focusing adjustment ring is rotatably connected to the lens barrel, and the focusing adjustment ring is coupled to the first lens 1 or the second lens 2 to adjust the distance between the first lens 1 and the second lens 2.

[0054] As described above, the distance between the first lens 1 and the second lens 2 is Z;

[0055] In one example, the focusing adjustment ring is coupled to the first lens 1 or the second lens 2, which can also be achieved through the meshing connection between a gear and an external gear ring, or through the meshing connection between a worm gear and a worm. This example is not limited to these.

[0056] For example, if the first lens 1 is fixedly disposed inside the lens barrel, then the second lens 2 is movably disposed inside the lens barrel, and the focusing adjustment ring is connected to the second lens 2, controlling the movement of the second lens 2 through the focusing adjustment ring; similarly, if the second lens 2 is fixedly disposed inside the lens barrel, then the first lens 1 is movably disposed inside the lens barrel, and the focusing adjustment ring is connected to the first lens 1, controlling the movement of the first lens 1 through the focusing adjustment ring; preferably, the second lens 2 is configured to be movably disposed inside the lens barrel; of course, this example is not limited to this.

[0057] In one embodiment, the refractive index of the third lens 3 is set to n3, and the Abbe number is set to V3, satisfying the following condition:

[0058] 1.83 < n3 < 2.1;

[0059] 18 < V3 < 25.

[0060] It should be noted that this embodiment only provides some preferred examples. The third lens 3 in this embodiment satisfies 1.83 < n3 < 2.1, 18 < V3 < 25; it is not limited to the values ​​of n3 being 1.85 and V3 being 22. It can also be other values ​​within the range of 1.83 < n3 < 2.1, 18 < V3 < 25. This embodiment is not limited to these values.

[0061] In one embodiment, the lenses used for the first lens 1, the second lens 2, the third lens 3, and the fourth lens 4 are all made of domestically produced optical glass, which can greatly reduce the manufacturing cost.

[0062] In one embodiment, the first lens 1 and the third lens 3 are made of high-refractive-index glass, and the second lens 2 is made of low-dispersion-coefficient glass. This effectively reduces aberrations in the lens's optical system, making the lens structure simpler and easier to manufacture, and also improving the imaging effect.

[0063] like Figure 2 As shown, Figure 2 The propagation path of light entering this embodiment is shown in the diagram. The optical performance of this embodiment is verified through specific experiments below; the results are as follows... Figures 3 to 5 As shown.

[0064] Figure 3 In the graph, the horizontal axis represents the spatial frequency of line pairs per millimeter (lp / mm), and the vertical axis represents the MTF value. A higher curve indicates better image quality. OTF stands for optical transfer function; in this embodiment, the vertical axis represents the optical modulation transfer function, or MTF.Figure 3 As can be seen, this embodiment exhibits good contrast within a spatial frequency range of 100 lp / mm, indicating that the overall resolution of this embodiment is high.

[0065] like Figure 4 This is a schematic diagram of field curvature and distortion of the lens in this embodiment. It is a transverse aberration that only changes the position of the off-axis image convergence point and does not affect the image sharpness.

[0066] like Figure 5 The diagram shown is a dot plot of the lens's field of view (FIELD) in this embodiment. The values ​​below the table indicate that smaller values ​​represent better image quality. It can be seen that the imaging points in each field of view almost converge into a single, ideal point, indicating that this embodiment has excellent imaging performance.

[0067] The verification results show that the lens of this embodiment has excellent optical performance, is not only simple in structure, lightweight and low in cost, but can also form images at infinity.

[0068] This embodiment provides a wide-angle drone lens with advantages of simple structure, low cost, and light weight. The wide-angle drone lens operates in the visible light band and can image at infinite distances; it is particularly suitable for drone surveying scenarios. In addition, the lenses used in each lens can be made of domestically produced optical glass, which can greatly reduce the lens manufacturing and usage costs. The second lens 2 can be made of low dispersion glass, and the first lens 1 and the third lens 3 can be made of high refractive index glass, which effectively reduces aberrations in the lens's optical system, making the structure simple and easy to manufacture, improving the imaging effect, and reducing manufacturing costs.

[0069] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

[0070] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A wide-angle drone lens, characterized in that, The wide-angle drone lens includes: a first lens, a second lens, a third lens, and a fourth lens arranged sequentially along the optical axis from the object plane to the image plane; The first lens is a meniscus negative diopter lens with the convex surface facing the object surface. The S1 surface of the first lens is the standard surface with a radius of curvature of 19.943 and a thickness of 1.

2. The S2 surface of the first lens is the standard surface with a radius of curvature of 7.644 and a thickness of 10.

11. The second lens is a meniscus positive diopter lens with the convex surface facing the object plane. The S3 surface of the second lens is the standard surface with a radius of curvature of 5.945 and a thickness of 3.

93. The S4 surface of the second lens is the standard surface with a radius of curvature of 263.297 and a thickness of 0.

11. The third lens has two even-order aspherical surfaces. The S6 surface of the third lens is an even-order aspherical surface with a radius of curvature of -8.966 and a thickness of 1. The S7 surface of the third lens is an even-order aspherical surface with a radius of curvature of -4.999 and a thickness of 1.

73. The fourth lens is a biconvex positive diopter lens. The S8 surface of the fourth lens is a standard surface with a radius of curvature of 255.433 and a thickness of 3.

41. The S9 surface of the fourth lens is a standard surface with a radius of curvature of -14.492 and a thickness of 13.

41. The wide-angle drone lens has a focal length f = 16mm and a total optical length ∑ = 38.6mm.

2. The wide-angle drone lens according to claim 1, characterized in that, An aperture is provided between the second lens and the third lens.

3. The wide-angle drone lens according to claim 1 or 2, characterized in that, The distance between the first lens and the second lens is Z. .

4. The wide-angle drone lens according to claim 3, characterized in that, The distance Z between the first lens and the second lens is 10.11 mm.

5. The wide-angle drone lens according to claim 1, characterized in that, The first lens and the fourth lens satisfy the following conditions: ； in, The effective focal length of the first lens. This is the effective focal length of the fourth lens.

6. The wide-angle drone lens according to claim 1, characterized in that, The refractive index of the third lens is set to Abbe number is set as It satisfies the following condition: ； 。 7. The wide-angle drone lens according to claim 2, characterized in that, The wide-angle drone lens also includes a lens barrel, and the first lens, the second lens, the third lens and the fourth lens are disposed inside the lens barrel.

8. The wide-angle drone lens according to claim 7, characterized in that, An aperture adjustment ring is rotatably connected to the lens barrel. The aperture adjustment ring is coupled to the aperture and is used to adjust the amount of light transmitted through the aperture.

9. The wide-angle drone lens according to claim 7, characterized in that, A focusing adjustment ring is rotatably connected to the lens barrel. The focusing adjustment ring is coupled to the first lens or the second lens and is used to adjust the distance between the first lens and the second lens.

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