Light supplementing device and camera device
By using LED light sources and nested circular metasurface design in fill light devices, uniform distribution of light is achieved, solving the problems of insufficient brightness uniformity and strong glare sense in existing fill light devices, and improving the effect of image acquisition.
Patent Information
- Application Number
- CN202510590055.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-07
- Publication Date
- 2025-07-29
AI Technical Summary
When collecting images, the existing fill light devices have strong glare and insufficient brightness uniformity, resulting in unclear images.
An LED light source is used to combine the circular first metasurface and the second metasurface, the first metasurface is used to collimate the light, and the second metasurface disperses the central light to the edge through a nested circular ring-shaped hyperlens to ensure uniform distribution of the light.
The brightness uniformity of the light beam emitted by the fill light device is improved, the glare feeling is reduced, and the clarity of image acquisition is improved.
Smart Images
Figure CN120385052A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of optical imaging technology, and particularly to a supplementary lighting device and a camera device. Background Art
[0002] With the development of technology, in the transportation field, image acquisition devices such as cameras are usually used to acquire images, and the vehicles running on the road are managed based on the acquired images. Among them, in order to make the acquired images clearer, a supplementary lighting device is turned on for supplementary lighting during image acquisition.
[0003] However, the existing supplementary lighting device has the hazard of dazzling people's eyes, resulting in too strong glare for passers-by and drivers. Under the existing conditions, improving the brightness uniformity and reducing the average brightness are the keys to reducing glare. Therefore, how to improve the brightness uniformity of the light beam emitted by the supplementary lighting device has become a problem to be solved. Summary of the Invention
[0004] This application provides a supplementary lighting device and a camera device, which are used to improve the brightness uniformity of the light beam emitted by the supplementary lighting device, thereby reducing the glare of the supplementary lighting device.
[0005] In a first aspect, an embodiment of this application provides a supplementary lighting device, which includes: an LED, a circular first metasurface, and a second metasurface; wherein, the second metasurface includes: a circular first metalens, and at least one annular second metalens nested outside the first metalens, and the focal length of the first metalens is less than the focal length of any second metalens; the diameter of the nested second metasurface is the same as the diameter of the first metasurface;
[0006] The light incident side of the first metasurface is located on the light emitting side of the LED, the light incident side of the second metasurface is located on the light emitting side of the first metasurface, and the center of the LED, the center of the first metasurface, and the center of the first metalens are on the same straight line.
[0007] Further, the connection line between the focus of the first metalens and the two end points of any diameter of the first metalens forms a first included angle, which is less than the second included angle formed by the connection line between the focus of any second metalens and the two end points of any outer circle diameter of the second metalens.
[0008] Further, if the number of the second metalenses is at least two, the second included angle corresponding to the second metalens closer to the first metalens is smaller.
[0009] Further, if the number of the second metalenses is at least two, the focal length of the second metalens closer to the first metalens is smaller.
[0010] Further, for each second metalens, the focal length and the second included angle of the second metalens satisfy the following formula:
[0011]
[0012] where θ n is the second included angle of the second metalens, f n is the focal length of the second metalens, f1 is the focal length of the first metalens, r1 is the radius of the first metalens, and D is a preset irradiation distance.
[0013] Further, for each second metalens, the second metalens includes a plurality of circular sub-metalenses, and each sub-metalens is arranged in sequence to form the second metalens. Among them, the focal lengths of each sub-metalens are the same, and the diameter of each sub-metalens is the difference between the outer circle radius and the inner circle radius of the second metalens.
[0014] Further, the closer the second metalens is to the first metalens, the smaller the focal length of the sub-metalenses included in the second metalens.
[0015] Further, for each sub-metalens, the connection lines between the focus of the sub-metalens and the two endpoints of any diameter of the sub-metalens form a third included angle, which is smaller than the first included angle formed by the connection lines between the focus of the first metalens and the two endpoints of any diameter of the first metalens.
[0016] Further, for each second metalens, the focal lengths of each sub-metalens included in the second metalens satisfy the following formula:
[0017]
[0018] where r n is the outer circle radius of the second metalens, r n-1 is the inner circle radius of the second metalens, f n is the focal length of the second metalens, f1 is the focal length of the first metalens, r1 is the radius of the first metalens, and D is a preset irradiation distance.
[0019] In a second aspect, an embodiment of the present application further provides a camera device, and the camera device includes: using the light supplementing device described in any one of the above for light supplementing.
[0020] In the embodiment of the present application, the light supplementing device includes a circular first metasurface and a second metasurface, and in combination with an LED light source, uniform distribution of light can be achieved. Among them, the first metasurface is used to preliminarily collimate and modulate the light emitted by the LED, and the second metasurface disperses the light at the center to the edge through the first metalens, and then maintains the light at the original edge through the nested second metalens, so that the light can be evenly distributed in each area. Brief Description of the Drawings
[0021] To more clearly illustrate the technical solutions of this application, the following briefly introduces the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of this application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.
[0022] Figure 1 Schematic structural diagram of a light supplement device provided by an embodiment of this application;
[0023] Figure 2 Schematic diagram of a second metasurface divided into three regions provided by an embodiment of this application;
[0024] Figure 3 Schematic diagram of a design of the focal length of the second metasurface partition provided by an embodiment of this application;
[0025] Figure 4 Schematic diagram of a partition of the second metasurface provided by an embodiment of this application;
[0026] Figure 5 Another schematic diagram of the design of the focal length of the second metasurface partition provided by an embodiment of this application. Detailed Description of the Embodiments
[0027] To make the objectives, technical solutions, and advantages of this application clearer, the following will further describe this application in detail with reference to the drawings. Obviously, the described embodiments are only some embodiments of this application, rather than all embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of this application.
[0028] To improve the brightness uniformity of the light beam emitted by the light supplement device and reduce the dizziness of the light supplement device, an embodiment of this application provides a light supplement device and a camera device. In the embodiment of this application, the light supplement device includes: an LED, a circular first metasurface, and a second metasurface; wherein, the second metasurface includes: a circular first superlens, and at least one annular second superlens nested outside the first superlens, the focal length of the first superlens is less than the focal length of any second superlens; the diameter of the nested second metasurface is the same as the diameter of the first metasurface; the incident side of the first metasurface is located on the light-emitting side of the LED, the incident side of the second metasurface is located on the light-emitting side of the first metasurface, and the center of the LED, the center of the first metasurface, and the center of the first superlens are on the same straight line.
[0029] Embodiment 1:
[0030] Figure 1 The figure is a schematic structural diagram of a supplementary light device provided by an embodiment of the present application. The supplementary light device includes: an LED (3), a circular first metasurface (1), and a second metasurface (2); wherein, the second metasurface includes: a circular first superlens, and at least one annular second superlens nested outside the first superlens, and the focal length of the first superlens is less than the focal length of any second superlens; the diameter of the second metasurface obtained by nesting is the same as the diameter of the first metasurface;
[0031] The light incident side of the first metasurface is located on the light emitting side of the LED, the light incident side of the second metasurface is located on the light emitting side of the first metasurface, and the center of the LED, the center of the first metasurface, and the center of the first superlens are on the same straight line.
[0032] In the embodiment of the present application, the supplementary light device includes an LED (3), a circular first metasurface (1), and a circular second metasurface (2). The light incident side of the first metasurface (1) is located on the light emitting side of the LED (3), the light incident side of the second metasurface (2) is located on the light emitting side of the first metasurface (1), and the center of the LED (3), the center of the first metasurface (1), and the center of the second metasurface (2) are on the same straight line. The first metasurface (1) and the second metasurface (2) have the same size and shape.
[0033] In the embodiment of the present application, the first metasurface is a collimating lens, which is used to collimate the light beam emitted by the LED. After the light beam emitted by the LED passes through the first metasurface, it is transformed into a light beam perpendicular to the second metasurface.
[0034] The second metasurface includes a circular first superlens, and at least one annular second superlens nested outside the first superlens. The focal length of the first superlens is less than the focal length of any second superlens; the diameter of the second metasurface obtained by nesting is the same as the diameter of the first metasurface.
[0035] In a possible implementation manner, the second metasurface is divided into n regions (n≥2). Taking n = 3 as an example, Figure 2 The figure is a schematic diagram of the second metasurface divided into three regions provided by an embodiment of the present application. As shown in the Figure 2 figure, the overall size of the second metasurface is a circle with a radius of r3, which is divided into a circular first superlens with a radius of r1, a circular ring-shaped second superlens with an inner diameter of r1 and an outer diameter of r2, and another circular ring-shaped second superlens with an inner diameter of r2 and an outer diameter of r3.
[0036] In the embodiments of the present application, the center of the LED light source, the center of the first metasurface, and the center of the first metalens are located on the same straight line, ensuring that the light transmission path is symmetric and uniform. The first metasurface is used to collimate and modulate the light emitted by the LED, and the second metasurface further focuses and diffuses the light to form a uniform fill light effect.
[0037] In the embodiments of the present application, the fill light device includes a circular first metasurface and a second metasurface, and in combination with the LED light source, it enables uniform distribution of light. Among them, the first metasurface is used to preliminarily collimate and modulate the light emitted by the LED, and the second metasurface disperses the light at the center to the edge through the first metalens, and then maintains the light at the original edge through the nested second metalens, so that the light can be evenly distributed in each area.
[0038] Embodiment 2:
[0039] In order to improve the brightness uniformity of the light beam emitted by the fill light device and reduce the dizziness of the fill light device, based on the above embodiments, in the embodiments of the present application, the connection line between the focus of the first metalens and the two end points of any diameter of the first metalens forms a first angle, which is smaller than the connection line between the focus of any second metalens and the two end points of any outer circle diameter of the second metalens to form a second angle.
[0040] In the embodiments of the present application, in the design of the first metalens, the connection line between its focus and the two end points of any diameter forms a first angle. And in the second metalens, the connection line between its focus and the two end points of any outer circle diameter forms a second angle. The first angle is smaller than the second angle, and this design enables the light in the central area to gradually spread to the peripheral area, forming a uniform fill light effect.
[0041] Figure 3 A schematic diagram of the focal length design of the second metasurface partition provided for the embodiments of the present application. As shown in Figure 3 the figure, the circle with a radius of r1 is the first metalens, its focal length is f1, corresponding to the θ1 angle, and tan(θ1 / 2) = r1 / f1. The ring with an inner diameter of r1 and an outer diameter of r2 is a second metalens, its focal length is f2, corresponding to the θ2 angle, and tan(θ2 / 2) = r2 / f2. The ring with an inner diameter of r2 and an outer diameter of r3 is another second metalens, its focal length is f3, corresponding to the θ3 angle, and tan(θ3 / 2) = r3 / f3. Among them, θ1 > θ2 > θ3, f1 < f2 < f3, and it satisfies that at a distance D from the LED, the light beam modulated by the 3 lenses can just reach the edge Z point.
[0042] Due to the above relationship, the energy at the center is dispersed to the edge by the first superlens with a radius of r1 and the second superlens with an inner diameter of r1 and an outer diameter of r2. At the same time, the second superlens with an inner diameter of r2 and an outer diameter of r3 maintains the original edge energy, thereby making the light output more uniform.
[0043] Embodiment 3:
[0044] In order to improve the brightness uniformity of the light beam emitted by the supplementary lighting device and reduce the dizziness feeling of the supplementary lighting device, based on the above embodiments, in the embodiments of the present application, if the number of the second superlenses is at least two, the smaller the second angle corresponding to the second superlens closer to the first superlens.
[0045] In the embodiments of the present application, when the number of the second superlenses is at least two, the smaller the second angle corresponding to the second superlens closer to the first superlens. For example, assume that the number of the second superlenses is three, and from the inside to the outside are the second superlenses A, B, and C. The second angle θ of the second superlens A A = 12°, the second angle θ of the second superlens B B = 18°, the second angle θ of the second superlens C C = 25°. This design makes the diffusion of light from the center to the periphery smoother and the supplementary lighting effect more uniform.
[0046] In the actual application process, the second angle θ can be precisely controlled by adjusting the microstructure parameters (such as period, height, and shape) of each second superlens to ensure that the light distribution meets the design requirements; the second angle can also be controlled by adjusting the focal length, radius, etc. of each second superlens.
[0047] Embodiment 4:
[0048] In order to improve the brightness uniformity of the light beam emitted by the supplementary lighting device and reduce the dizziness feeling of the supplementary lighting device, based on the above embodiments, in the embodiments of the present application, if the number of the second superlenses is at least two, the smaller the focal length corresponding to the second superlens closer to the first superlens.
[0049] In the embodiments of the present application, when the number of the second superlenses is at least two, the smaller the focal length corresponding to the second superlens closer to the first superlens. For example, assume that the focal length of the first superlens is f1 = 10 mm, the focal length of the second superlens A is f2A = 12 mm, the focal length of the second superlens B is f2B = 18 mm, and the focal length of the second superlens C is f2C = 25 mm. This gradient change in the focal length makes the light in the central region disperse to the periphery, forming a uniform supplementary lighting effect.
[0050] In the actual application process, the focal length can be precisely controlled by adjusting the curvature and microstructure parameters of each second metalens, ensuring that the focusing and diffusion effects of light meet the design requirements.
[0051] In order to improve the brightness uniformity of the light beam emitted by the supplementary lighting device and reduce the dizziness of the supplementary lighting device, based on the above embodiments, in the embodiments of the present application, for each second metalens, the focal length and the second included angle of the second metalens satisfy the following formula:
[0052]
[0053] where θ n is the second included angle of the second metalens, f n is the focal length of the second metalens, f1 is the focal length of the first metalens, r1 is the radius of the first metalens, and D is the preset irradiation distance.
[0054] In the embodiments of the present application, the light beam modulated by each metalens of the second metasurface can be uniformly propagated to a preset position. Among them, for each second metalens, the focal length and the second included angle of the second metalens satisfy the following formula:
[0055]
[0056] where θ n is the second included angle of the second metalens, f n is the focal length of the second metalens, f1 is the focal length of the first metalens, r1 is the radius of the first metalens, and D is the preset irradiation distance.
[0057] Exemplarily, if the second metasurface includes one first metalens and two second metalenses, the following relational expressions are satisfied:
[0058]
[0059] where θ2 is the second included angle of one second metalens, f2 is the focal length of this second metalens, f1 is the focal length of the first metalens, r1 is the radius of the first metalens, and D is the preset irradiation distance; θ3 is the second included angle of the other second metalens, and f3 is the focal length of this second metalens.
[0060] Embodiment 5:
[0061] In order to improve the brightness uniformity of the light beam emitted by the supplementary lighting device and reduce the dizziness feeling of the supplementary lighting device, based on the above embodiments, in the embodiments of the present application, for each second superlens, the second superlens includes a plurality of circular sub-superlenses, and each sub-superlens is arranged in sequence to form the second superlens. Among them, the focal lengths of each of the sub-superlenses are the same, and the diameter of each of the sub-superlenses is the difference between the outer circle radius and the inner circle radius of the second superlens.
[0062] In the embodiments of the present application, in order to further improve the brightness uniformity of the light beam emitted by the supplementary lighting device, each second superlens may be composed of a plurality of circular sub-superlenses, and these sub-superlenses are arranged in sequence to form the second superlens. Among them, the focal lengths of each of the sub-superlenses belonging to the same second superlens are the same, which is the focal length of the second superlens, and the diameter of each of the sub-superlenses is the difference between the outer circle radius and the inner circle radius of the second superlens. For example, assuming that the outer circle radius of the second superlens A is 10 mm and the inner circle radius is 8 mm, then the diameter of each sub-superlens is 2 mm.
[0063] Figure 4 A schematic diagram of the partition of a second metasurface provided by the embodiments of the present application is as follows. As shown in Figure 4 the figure, the circle with a radius of r1 is the first superlens; the ring with an inner diameter of r1 and an outer diameter of r2 is a second superlens, which is composed of a plurality of circular sub-superlenses, and the diameter of each sub-superlens is r2 - r1 ( Figure 4 the black circles shown in the figure are one superlens); the ring with an inner diameter of r2 and an outer diameter of r3 is another second superlens, which is composed of a plurality of circular sub-superlenses, and the diameter of each sub-superlens is r3 - r2.
[0064] In the actual application process, the microstructures of the sub-superlenses can be fabricated on the transparent substrate through a lithography process to ensure that their optical properties meet the design requirements.
[0065] Embodiment 6:
[0066] In order to improve the brightness uniformity of the light beam emitted by the supplementary lighting device and reduce the dizziness feeling of the supplementary lighting device, based on the above embodiments, in the embodiments of the present application, the closer the second superlens is to the first superlens, the smaller the focal length of the sub-superlenses included in the second superlens.
[0067] In the embodiments of the present application, the closer the second superlens is to the first superlens, the smaller the focal length of the sub-superlenses included in the second superlens. For example, assuming that the focal length of the sub-superlenses of the second superlens A is f3A = 4 mm, then the focal length of the sub-superlenses of the second superlens B is f3B = 5 mm, and the focal length of the sub-superlenses of the second superlens C is f3C = 6 mm. This design further enhances the light homogenization effect of the supplementary lighting device, making the light more uniform.
[0068] In the actual application process, by adjusting the curvature and microstructure parameters of the sub-superlens, its focal length is precisely controlled to ensure that the focusing effect of light meets the design requirements.
[0069] In order to improve the brightness uniformity of the light beam emitted by the fill light device and reduce the dizziness caused by the fill light device, based on the above embodiments, in the embodiments of the present application, for each sub-superlens, the third included angle formed by the connection lines between the focus of the sub-superlens and the two endpoints of any diameter of the sub-superlens is smaller than the first included angle formed by the connection lines between the focus of the first superlens and the two endpoints of any diameter of the first superlens.
[0070] In the embodiments of the present application, for each sub-superlens, the third included angle θ3 formed by the connection lines between its focus and the two endpoints of any diameter of the sub-superlens, and θ3 is smaller than the first included angle θ1 of the first superlens. For example, assuming that the first included angle θ1 of the first superlens is 10°, and the third included angle θ3 of the sub-superlens is 5°, this design ensures that the light distribution of the sub-superlens is more uniform and further optimizes the fill light effect.
[0071] In the actual application process, through numerical simulation and experimental verification, the design parameters of the sub-superlens are optimized to ensure that it meets the above angular relationship.
[0072] Embodiment 7:
[0073] In order to improve the brightness uniformity of the light beam emitted by the fill light device and reduce the dizziness caused by the fill light device, based on the above embodiments, in the embodiments of the present application, for each second superlens, the focal length of each sub-superlens included in the second superlens satisfies the following formula:
[0074]
[0075] where r n is the outer circle radius of the second superlens, r n-1 is the inner circle radius of the second superlens, f n is the focal length of the second superlens, f1 is the focal length of the first superlens, r1 is the radius of the first superlens, and D is the preset irradiation distance.
[0076] In the embodiments of the present application, for each second superlens, the focal length of each sub-superlens included in the second superlens satisfies the following formula:
[0077]
[0078] where r n is the outer circle radius of the second superlens, r n-1 is the inner circle radius of the second superlens, f nis the focal length of the second metalens, f1 is the focal length of the first metalens, r1 is the radius of the first metalens, and D is the preset irradiation distance.
[0079] Based on Figure 4 , Figure 5 FIG. is another schematic diagram of the focal length design of the second metasurface partition provided by the embodiment of the present application. As shown in the Figure 5 , the focal length of the first metalens with a radius of r1 is f1, corresponding to the angle θ1, and tan(θ1 / 2) = r1 / f1. The second metalens with an inner diameter of r1 and an outer diameter of r2 is composed of a plurality of circular sub-metalenses. The diameter of each sub-metalens is r2 - r1, and the focal length is f2, corresponding to the angle θ2, and tan(θ2 / 2) = (r2 - r1) / f2. The second metalens with an inner diameter of r2 and an outer diameter of r3 is composed of a plurality of circular sub-metalenses. The diameter of each sub-metalens is r3 - r2, and its focal length is f3, corresponding to the angle θ3, and tan(θ3 / 2) = (r3 - r2) / f3.
[0080] Where r1, r2, r3, f1, f2, and f3 satisfy the following relationship:
[0081]
[0082] In the embodiment of the present application, by partitioning the second metasurface, and the focal lengths and diameters of the metalenses in different regions are different, the control of different exit angles is realized, and then the energy is redistributed to achieve uniform light output, and it can be designed according to different angle requirements. The supplementary light device provided by the embodiment of the present application only uses two metasurfaces, with a simple and compact structure and a small volume.
[0083] Embodiment 8:
[0084] Based on the same inventive concept, the present invention also provides a camera device, which includes: using the supplementary light device in any of the above embodiments for supplementary light.
[0085] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.
[0086] This application is described with reference to the flowcharts and / or block diagrams of methods, apparatus (systems), and computer program products according to the application. It should be understood that each flow and / or block in the flowchart and / or block diagram, and the combination of flows and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing device produce means for implementing the functions specified in one flow Figure 1 one or more flows and / or blocks Figure 1 or means for implementing the functions specified in one block or more blocks.
[0087] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory produce a manufactured article including instruction means that implement the functions specified in one flow Figure 1 one or more flows and / or blocks Figure 1 or means for implementing the functions specified in one block or more blocks.
[0088] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operational steps are performed on the computer or other programmable device to generate a computer-implemented process, and thus the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one flow Figure 1 one or more flows and / or blocks Figure 1 or means for implementing the functions specified in one block or more blocks.
[0089] Obviously, those skilled in the art can make various changes and modifications to this application without departing from the spirit and scope of this application. Thus, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalent technologies, this application is also intended to include these changes and modifications.
Claims
1. A supplementary lighting device, characterized in that, The supplementary light device includes: an LED, a circular first metasurface, and a second metasurface; wherein, the second metasurface includes: a circular first metalens, and at least one annular second metalens nested outside the first metalens, the focal length of the first metalens is less than the focal length of any second metalens; the diameter of the nested second metasurface is the same as the diameter of the first metasurface; The light incident side of the first metasurface is located on the light emitting side of the LED, the light incident side of the second metasurface is located on the light emitting side of the first metasurface, and the center of the LED, the center of the first metasurface, and the center of the first metalens are on the same straight line.
2. The supplementary lighting device according to claim 1, wherein The connection lines between the focus of the first metalens and the two endpoints of any diameter of the first metalens form a first included angle, which is less than the second included angle formed by the connection lines between the focus of any second metalens and the two endpoints of any outer circle diameter of the second metalens.
3. The supplementary lighting device according to claim 2, wherein If the number of the second metalenses is at least two, the second included angle corresponding to the second metalens closer to the first metalens is smaller.
4. The supplementary lighting device according to claim 3, wherein If the number of the second metalenses is at least two, the focal length of the second metalens closer to the first metalens is smaller.
5. The supplementary lighting device according to claim 4, wherein For each second metalens, the focal length and the second included angle of the second metalens satisfy the following formula: where θ n is the second included angle of the second metalens, f n is the focal length of the second metalens, f1 is the focal length of the first metalens, r1 is the radius of the first metalens, and D is a preset irradiation distance.
6. The supplementary lighting device according to claim 1, wherein For each second metalens, the second metalens includes a plurality of circular sub-metalenses, and each sub-metalens is arranged in sequence to form the second metalens. Among them, the focal lengths of each sub-metalens are the same, and the diameter of each sub-metalens is the difference between the outer circle radius and the inner circle radius of the second metalens.
7. The supplementary lighting device according to claim 6, characterized in that, The focal length of the sub-metalenses included in the second metalens closer to the first metalens is smaller.
8. The supplementary lighting device according to claim 6, wherein For each sub-metalens, the connection lines between the focus of the sub-metalens and the two endpoints of any diameter of the sub-metalens form a third included angle, which is less than the first included angle formed by the connection lines between the focus of the first metalens and the two endpoints of any diameter of the first metalens.
9. The supplementary lighting device according to claim 6, characterized in that, For each second metalens, the focal lengths of each sub-metalens included in the second metalens satisfy the following formula: where r n is the outer circle radius of the second metalens, r n-1 is the inner circle radius of the second metalens, f n is the focal length of the second metalens, f1 is the focal length of the first metalens, r1 is the radius of the first metalens, and D is a preset irradiation distance.
10. An imaging device, characterized in that, The imaging device is equipped with: using the supplementary light device described in any one of claims 1 to 9 above for supplementary light.