Metasurface lens and camera module

Abstract

This application discloses a metasurface lens and a camera module, belonging to the field of imaging technology. The metasurface lens includes a transparent substrate and multiple sets of nanopillars. By configuring at least two nanopillars in each set of nanopillars in the metasurface lens to correspond to at least two wavelengths of visible light, and ensuring that the transmittance of each nanopillar for the corresponding wavelength of visible light is greater than the transmittance for other wavelengths, when visible light is incident on the metasurface lens, each nanopillar has a higher transmittance only for the corresponding wavelength of visible light, while having a lower transmittance for other wavelengths. This ensures that the energy of visible light of different wavelengths is higher only in the corresponding nanopillars and lower in other nanopillars, thereby effectively eliminating interference between different wavelengths of visible light and effectively eliminating chromatic aberration when visible light passes through the metasurface lens.

Description

Technical Field

[0001] This application relates to the field of camera technology, and in particular to a metasurface lens and camera module. Background Technology

[0002] Metasurface materials are materials capable of directly manipulating various elements of electromagnetic waves at the nanoscale, such as amplitude, phase, polarization direction, and propagation direction. Lenses designed from metasurface materials are called superlenses. Superlenses have extremely flat and compact surfaces, and their nanoscale subwavelength structures exhibit excellent wavefront shaping performance. Furthermore, superlenses are significantly lighter and smaller than traditional lenses, simplifying complex lens assembly structures into one or a few nanolayers, which is beneficial for integrated lens applications.

[0003] However, some camera modules that integrate super lenses still exhibit chromatic aberration during shooting. Summary of the Invention

[0004] This application provides a metasurface lens and a camera module. It solves the problem of color aberration in existing camera modules. The technical solution is as follows:

[0005] On one hand, a metasurface lens is provided, the metasurface lens comprising:

[0006] Transparent substrate and multiple nanopillars;

[0007] The transparent substrate has multiple lens regions arranged in an array;

[0008] The multiple sets of nanopillars correspond one-to-one with the multiple lens regions. Each set of nanopillars contains at least two nanopillars, and each nanopillar in each set is fixedly connected to the transparent substrate within the corresponding lens region.

[0009] In a set of nanopillars, at least two nanopillars correspond to at least two wavelengths of visible light, and the transmittance of each nanopillar to the corresponding wavelength of visible light is greater than its transmittance to other wavelengths of visible light.

[0010] Optionally, in a set of nanopillars, the area of ​​the orthographic projection of each nanopillar onto the transparent substrate is different.

[0011] Optionally, in any two different sets of nanopillars, the areas of the orthographic projections of the two nanopillars corresponding to the same visible light band on the transparent substrate are the same.

[0012] Optionally, the orthographic projection of each of the nanopillars onto the transparent substrate is rectangular; in any two different sets of nanopillars, the orthographic projections of the two nanopillars corresponding to the same visible light band onto the transparent substrate have the same length and the same width.

[0013] Optionally, the length of the orthographic projection of the nanopillar on the transparent substrate ranges from 50 nanometers to 350 nanometers, and the width of the orthographic projection of the nanopillar on the transparent substrate ranges from 50 nanometers to 350 nanometers.

[0014] Optionally, in a set of nanopillars, each nanopillar has a transmittance of visible light in a corresponding wavelength band greater than or equal to a first threshold, and a transmittance of visible light in other wavelength bands less than or equal to a second threshold, wherein the first threshold is greater than the second threshold.

[0015] Optionally, each group of nanopillars comprises four nanopillars arranged in two rows and two columns, and the shape enclosed by the center line connecting the orthographic projections of the four nanopillars onto the transparent substrate is a square.

[0016] Optionally, all of the nanopillars have the same height.

[0017] Optionally, the height of the nanopillars ranges from 200 nanometers to 700 nanometers.

[0018] Optionally, at least some of the nanopillars in the plurality of groups of nanopillars have different angles between the length direction of their orthographic projection on the transparent substrate and the reference direction. The reference direction is the direction of any coordinate axis in the target coordinate system of the metasurface lens, and the origin of the target coordinate system coincides with the center of the metasurface lens.

[0019] Optionally, the angle between the length direction of the orthographic projection of the nanopillar onto the transparent substrate and the reference direction satisfies the following relationship:

[0020]

[0021] Wherein, θ represents the angle between the length direction of the orthographic projection of the nanopillar onto the transparent substrate and the reference direction; τ represents the propagation phase value obtained when visible light of each wavelength band passes through the corresponding nanopillar; λ represents the phase of the visible light in the corresponding wavelength band after adjustment by the nanopillar; r represents the radial coordinate value of the nanopillar on the metasurface lens; λ i λ represents the center wavelength of visible light corresponding to the band of the nanopillar; F represents the focal length of the metasurface lens.

[0022] On the other hand, a camera module is provided, the camera module comprising:

[0023] The camera and the metasurface lens, wherein the metasurface lens is any of the metasurface lenses given above.

[0024] The beneficial effects of the technical solutions provided in this application include at least the following:

[0025] A metasurface lens may include a transparent substrate and multiple sets of nanopillars. By configuring at least two nanopillars in each set of nanopillars in the metasurface lens to correspond to at least two wavelengths of visible light, and ensuring that the transmittance of each nanopillar for its corresponding wavelength of visible light is greater than that for other wavelengths, when visible light is incident on the metasurface lens, each nanopillar has higher transmittance only for its corresponding wavelength and lower transmittance for other wavelengths. This ensures that visible light of different wavelengths has higher energy only in its corresponding nanopillars and lower energy in other nanopillars, effectively eliminating interference between different wavelengths of visible light and effectively eliminating chromatic aberration when visible light passes through the metasurface lens. Furthermore, since at least two wavelengths cover the visible light spectrum, the utilization efficiency of visible light is guaranteed. In addition, integrating this metasurface lens into a camera module can reduce the number of optical lenses in the camera module, effectively reducing the size of the camera module. Furthermore, it can effectively reduce the size of terminal devices that integrate the camera module, while ensuring that the terminal device is lightweight. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a top view of a metasurface lens provided in an embodiment of this application;

[0028] Figure 2 yes Figure 1 A magnified view of a portion of region A;

[0029] Figure 3 yes Figure 1 The side view of the metasurface lens is shown.

[0030] Figure 4 This is a partial schematic diagram of the top view of a metasurface lens;

[0031] Figure 5 This is a schematic diagram of a partially transparent substrate and a single nanopillar in a metasurface lens provided in an embodiment of this application;

[0032] Figure 6 This is a schematic diagram illustrating the correspondence between visible light transmittance and wavelength bands provided in an embodiment of this application;

[0033] Figure 7 This is a top view of a single nanopillar on a transparent substrate;

[0034] Figure 8 This is an illustration of the effect of a metasurface lens focusing light, provided in an embodiment of this application.

[0035] Figure 9 This is a schematic diagram of the structure of a camera module provided in an embodiment of this application.

[0036] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0038] Please refer to Figure 1 , Figure 2 and Figure 3 , Figure 1 This is a top view of a metasurface lens provided in an embodiment of this application. Figure 2 yes Figure 1 A magnified view of a portion of region A. Figure 3 yes Figure 1 The diagram shows a side view of a metasurface lens. The metasurface lens 000 may include: a transparent substrate 100 and multiple sets of nanopillars 200.

[0039] The transparent substrate 100 in the metasurface lens 000 can have multiple lens regions 101 arranged in an array.

[0040] In the metasurface lens 000, multiple sets of nanopillars 200 can correspond one-to-one with multiple lens regions 101. Each set of nanopillars 200 can contain at least two nanopillars 200, and each nanopillar in each set of nanopillars 200 is fixedly connected to the transparent substrate 100 within the corresponding lens region 101 (each nanopillar is fixedly connected to the same side of the transparent substrate). For example, each lens region 101 can contain at least two sub-lens regions corresponding one-to-one with at least two nanopillars 200, and the center of the orthographic projection of each nanopillar onto the transparent substrate coincides with the center of the corresponding sub-lens region.

[0041] In a group of nanopillars 200, at least two nanopillars 200 can correspond to at least two wavelengths of visible light (these at least two wavelengths are different bands within the visible light spectrum), and the transmittance of each nanopillar 200 for the corresponding wavelength of visible light can be greater than the transmittance of other wavelengths of visible light. In this application, the at least two wavelengths can be a portion of the visible light spectrum, or the at least two wavelengths can cover a range of visible light wavelengths. It should be noted that the following embodiments are illustrative examples of at least two wavelengths covering a range of visible light wavelengths.

[0042] In this embodiment, by configuring at least two nanopillars in each group of nanopillars 200 within the metasurface lens 000 to correspond to at least two wavelengths of visible light, and ensuring that the transmittance of each nanopillar 200 for its corresponding wavelength of visible light is greater than that for other wavelengths, when visible light is incident on the metasurface lens 000, each nanopillar 200 has a higher transmittance only for its corresponding wavelength of visible light, while having a lower transmittance for other wavelengths. This ensures that visible light of different wavelengths has higher energy only at its corresponding nanopillars and lower energy at other nanopillars, thus eliminating the chromatic aberration caused by other wavelengths of visible light. This effectively eliminates interference between different wavelengths of visible light, ultimately effectively eliminating the chromatic aberration phenomenon that occurs when visible light passes through the metasurface lens 000. Furthermore, since at least two wavelengths cover the visible light spectrum, the utilization efficiency of visible light is guaranteed. Furthermore, integrating this metasurface lens 000 into the camera module reduces the number of optical lenses in the camera module, effectively lowering its size. This also significantly reduces the size of the terminal device integrating the camera module while maintaining its weight.

[0043] In summary, this application provides a metasurface lens, which may include a transparent substrate and multiple sets of nanopillars. By configuring at least two nanopillars in each set of nanopillars in the metasurface lens to correspond to at least two wavelengths of visible light, and ensuring that the transmittance of each nanopillar for the corresponding wavelength of visible light is greater than the transmittance for other wavelengths, when visible light is incident on the metasurface lens, each nanopillar has a higher transmittance only for the corresponding wavelength of visible light, while having a lower transmittance for other wavelengths. This ensures that the energy of visible light of different wavelengths is higher only in the corresponding nanopillars and lower in other nanopillars, thereby effectively eliminating interference between different wavelengths of visible light and effectively eliminating chromatic aberration when visible light passes through the metasurface lens. Furthermore, since at least two wavelengths cover the visible light spectrum, the utilization efficiency of visible light is guaranteed. In addition, after integrating this metasurface lens into a camera module, the number of optical lenses in the camera module can be reduced, effectively reducing the size of the camera module. Furthermore, it can effectively reduce the size of terminal devices that integrate the camera module, while ensuring that the terminal device is lightweight.

[0044] Optional, please refer to Figure 4 , Figure 4 This is a partial schematic diagram of a top view of a metasurface lens. In a group of nanopillars 200, the areas of the orthographic projections of each nanopillar 200 onto the transparent substrate 100 within the metasurface lens 000 are different. In this case, by setting the areas of the orthographic projections of each nanopillar 200 onto the transparent substrate 100 within the metasurface lens 000 to be different, the group of nanopillars 200 can simultaneously modulate visible light. That is, when visible light is incident on the surface of the metasurface lens 000, a nanopillar 200 can have high transmittance for the visible light of the corresponding wavelength band and low transmittance for other wavelength bands, thereby modulating visible light through multiple groups of nanopillars 200 in the metasurface lens 000. For example, the number of visible light bands (at least two bands) can be four, namely, bands A1, A2, A3, and A4. A set of nanopillars 200 can contain four nanopillars: nanopillar B1, nanopillar B2, nanopillar B3, and nanopillar B4. When visible light is incident on the metasurface lens, nanopillar B1 exhibits higher transmittance for visible light in the A1 band, but lower transmittance for visible light in the A2, A3, and A4 bands; nanopillar B2 exhibits higher transmittance for visible light in the A2 band, but lower transmittance for visible light in the A1, A3, and A4 bands; nanopillar B3 exhibits higher transmittance for visible light in the A3 band, but lower transmittance for visible light in the A1, A2, and A4 bands; and nanopillar B4 exhibits higher transmittance for visible light in the A4 band, but lower transmittance for visible light in the A1, A2, and A3 bands.

[0045] In the embodiments of this application, such as Figure 4 As shown, in any two different sets of nanopillars 200, the areas of the orthographic projections of the two nanopillars 200 corresponding to the same wavelength of visible light on the transparent substrate 100 are the same. In this case, by setting the areas of the orthographic projections of the two nanopillars 200 corresponding to the same wavelength of visible light on the transparent substrate 100 in any two different sets of nanopillars 200, the influence of chromatic aberration when visible light passes through the metasurface lens is eliminated, while ensuring that the manufacturing process of the metasurface lens 000 is relatively simple.

[0046] Optional, please refer to Figure 3 and Figure 5 , Figure 5 This is a schematic diagram of a partially transparent substrate and a single nanopillar in a metasurface lens according to an embodiment of this application. The orthographic projection of each nanopillar 200 onto the transparent substrate 100 in the metasurface lens 000 can be rectangular. In any two different sets of nanopillars 200, the orthographic projections of the two nanopillars corresponding to the same wavelength of visible light onto the transparent substrate 100 have the same length L and the same width W. That is, when the orthographic projections of the two nanopillars corresponding to the same wavelength of visible light onto the transparent substrate 100 in any two different sets of nanopillars 200 are both rectangular, the length L of these two rectangles can be the same and the width W can be the same. In this case, by setting the orthographic projections of the two nanopillars 200 corresponding to the same wavelength of visible light onto the transparent substrate 100 in any two different sets of nanopillars 200 to have the same length L and the same width W, the influence of chromatic aberration generated when visible light passes through the metasurface lens 000 is further eliminated, while ensuring that the manufacturing process of the metasurface lens is relatively simple. It should be noted that in other possible implementations, the shape of the nanopillar can be an elliptical cylinder, and its cross-sectional shape can be elliptical.

[0047] In the embodiments of this application, such as Figure 5 As shown, the length L of the orthographic projection of the nanopillars 200 in the metasurface lens 000 onto the transparent substrate 100 can range from 50 nanometers to 350 nanometers; the width W of the orthographic projection of the nanopillars 200 in the metasurface lens 000 onto the transparent substrate 100 can also range from 50 nanometers to 350 nanometers. That is, when the orthographic projection of the nanopillars 200 in the metasurface lens 000 onto the transparent substrate 100 is rectangular, the length of the rectangle can range from 50 nanometers to 350 nanometers, and the width of the rectangle can also range from 50 nanometers to 350 nanometers.

[0048] Optionally, in a group of nanopillars 200 within the metasurface lens 000, each nanopillar has a transmittance of visible light in its corresponding wavelength band greater than or equal to a first threshold, and a transmittance of visible light in other wavelength bands less than or equal to a second threshold, where the first threshold can be greater than the second threshold. In this case, by setting the transmittance of each nanopillar for visible light in its corresponding wavelength band to be greater than or equal to the first threshold, and the transmittance for visible light in other wavelength bands to be less than or equal to the second threshold, the same first and second thresholds are set for different nanopillars, ensuring that the efficiency of visible light in each wavelength band passing through the metasurface lens 000 is basically consistent, and the brightness of the light is basically consistent. Furthermore, setting the first threshold to be greater than the second threshold ensures that each nanopillar 200 has a higher transmittance for visible light in its corresponding wavelength band and a lower transmittance for visible light in other wavelength bands, further effectively eliminating the chromatic aberration effect caused by visible light in other wavelength bands, thereby effectively eliminating interference between visible light in different wavelength bands, and ultimately effectively eliminating the chromatic aberration phenomenon generated when visible light passes through the metasurface lens.

[0049] Taking the wavelength range of incident visible light from 450 nm to 650 nm as an example, the selection process of the nanopillars 200 in the metasurface lens 000 is illustrated here:

[0050] First, the shape of the nanopillars is determined to be a rectangular prism, dividing the wavelength range of visible light into four bands. For example, the four bands can be: A1 band: 450 nm to 490 nm; A2 band: 500 nm to 540 nm; A3 band: 550 nm to 590 nm; and A4 band: 600 nm to 650 nm. In this application, the wavelength difference between each band can range from 20 nm to 100 nm, and the wavelength differences between different bands can be the same, different, or partially the same.

[0051] Then, the length of the cuboid pillars is selected to range from 50 nm to 350 nm, and the width of the cuboid pillars is also selected to range from 50 nm to 350 nm. A certain step size is chosen to simulate the transmittance values ​​of nanopillars of different structural sizes at different wavelengths, establishing an efficiency value database. For example, this certain step size can be 1 nm.

[0052] Next, different nanopillars are set to have transmittance greater than or equal to a first threshold for their corresponding wavelengths, and transmittance less than or equal to a second threshold for other visible light wavelengths. This allows for an initial selection from an efficiency database, identifying multiple nanopillar structures corresponding to the four visible light wavelengths. For example, the first threshold could be 10%, and the second threshold could be 5%.

[0053] Finally, for multiple nanopillar structures of the four types, a further comparative analysis of the efficiency values ​​yielded the length and width of each nanopillar structure. For example, in the A1 band (450 nm to 490 nm), the length of the nanopillar is 76 nm and the width is 54 nm; in the A2 band (500 nm to 540 nm), the length is 86 nm and the width is 72 nm; in the A3 band (550 nm to 590 nm), the length is 100 nm and the width is 86 nm; and in the A4 band (600 nm to 650 nm), the length is 126 nm and the width is 100 nm. It should be noted that during the selection of the cuboid-shaped nanopillars, all nanopillars had the same height. Please refer to [reference needed]. Figure 6 , Figure 6 This is a schematic diagram illustrating the correspondence between visible light transmittance and wavelength bands provided in an embodiment of this application. As can be seen from the figure, each nanopillar in a group of nanopillars has a high transmittance for visible light in its corresponding wavelength band, while the transmittance for visible light in other wavelength bands is low.

[0054] In the embodiments of this application, please refer to Figure 4 and Figure 7 , Figure 7 This is a top view of a single nanopillar on a transparent substrate. Each group of nanopillars 200 in the metasurface lens 000 can contain four nanopillars, which can be arranged in two rows and two columns. The shape formed by the center line connecting the orthographic projections of the four nanopillars 200 onto the transparent substrate 100 is a square. The shape of the lens region 101 on the transparent substrate 100 can be square, and the shape formed by the center line connecting the orthographic projections of the four nanopillars 200 onto the transparent substrate 100 can also be square. The centers of these two squares can coincide. In this application, the multiple groups of nanopillars 200 in the metasurface lens 000 are arranged periodically, and each nanopillar is also arranged periodically. The arrangement period of each nanopillar can range from 200 nanometers to 500 nanometers, for example, the arrangement period can be 350 nanometers. Thus, the periodic arrangement of the nanopillars 200 in the metasurface lens 000 enables a better imaging effect of light passing through the metasurface lens 000 and then being imaged by the camera module.

[0055] Optional, such as Figure 5As shown, the height H of each nanopillar 200 in the metasurface lens 000 can be the same. In this application, by using nanopillars 200 of different heights, the metasurface lens 000 can achieve different transmittances of visible light. For example, in this embodiment, to ensure the transmittance of visible light by the nanopillars 200, the height H of the nanopillars in the metasurface lens 000 can range from 200 nm to 700 nm. For example, the height of each nanopillar 200 in the metasurface lens 000 can be selected as 350 nm; this embodiment does not specifically limit this. In addition, after determining the length L, width W, and height H of the nanopillars in the metasurface lens 000, the nanopillars 200 can typically be made of at least one material selected from single-crystal silicon, amorphous silicon, and silicon nitride, and the transparent substrate 100 in the metasurface lens 000 can typically be made of visible light transparent materials such as glass or sapphire.

[0056] In the embodiments of this application, such as Figure 7 As shown, at least some of the nanopillars 200 in the metasurface lens 000 have different angles θ between their length directions and reference directions when projected onto the transparent substrate 100. This reference direction can be the direction of any coordinate axis in the target coordinate system of the metasurface lens 000, and the origin of this target coordinate system can coincide with the center of the metasurface lens 000. The projected length of the nanopillars 200 onto the transparent substrate 100 is typically strip-shaped; for example, it can be rectangular, with the long side of the projected length being the length direction. It should be noted that the target coordinate system refers to the two-dimensional coordinate system constructed on the transparent substrate 100 of the metasurface lens 000 during the design of the metasurface lens. The reference direction here can be the X-axis and Y-axis directions in the two-dimensional coordinate system. It should also be noted that... (The text abruptly ends here, likely due to an incomplete translation or source material.) Figure 8 , Figure 8 This is an illustration of the effect of a metasurface lens focusing light according to an embodiment of this application. The angle θ between the length direction of the orthographic projection of the nanopillar 200 onto the transparent substrate 100 and the reference direction is the turning angle of the nanopillar 200. By rotating the nanopillar 200 to change the turning angle, the magnitude of the geometric phase obtained by the transmitted light can be changed, thereby controlling the incident light. In this way, the light emitted from the metasurface lens 000 can be converged to a single focal point, which is the focal point of the metasurface lens 000. That is, the metasurface lens 000 can eliminate the chromatic aberration caused by light in the selected visible light band range.

[0057] Optionally, the angle θ between the length direction of the orthographic projection of the nanopillar 200 onto the transparent substrate 100 in the metasurface lens 000 and the reference direction can satisfy the following relationship:

[0058]

[0059] Where θ represents the angle between the length direction of the orthogonal projection of the nanopillar onto the transparent substrate in the metasurface lens and the reference direction; τ represents the propagation phase value obtained when visible light of each wavelength passes through the corresponding nanopillar; λ represents the phase of the visible light in the corresponding wavelength band after adjustment by the nanopillar; r represents the radial coordinate value of the nanopillar on the metasurface lens; λ i τ represents the center wavelength of visible light corresponding to the nanometer band; F represents the focal length of the metasurface lens. It should be noted that the value of τ can be obtained simultaneously with the transmittance simulation of the nanopillar during the nanopillar selection process described above. During calculation, the corresponding propagation phase value (which is related to the structural dimensions of the nanopillar) can be directly obtained from the selected nanopillar. If the coordinates of the center point of the orthographic projection of the nanopillar onto the transparent substrate in the metasurface lens are (x, y) in the two-dimensional coordinate system, then the coordinates of the center point of the orthographic projection of the nanopillar onto the transparent substrate and the radial coordinates have the following relationship: r 2 =x 2 +y 2 The focal length of a metasurface lens is set according to actual needs during the design process; for example, a focal length of 10 mm.

[0060] For ease of description, the angle between the length direction of the orthogonal projection of the nanopillar 200 onto the transparent substrate 100 in the metasurface lens 000 and the reference direction satisfies one of the following equations:

[0061] Defined as Formula 1.

[0062] The equations satisfying the angle between the length direction of the orthogonal projection of the nanopillar 200 onto the transparent substrate 100 in the metasurface lens 000 and the reference direction are as follows:

[0063] Defined as Formula 2.

[0064] By arranging the nanopillars 200 on the transparent substrate 100, the phase of the nanopillar adjusted for the corresponding visible light band can be calculated using Equation 2, based on the center wavelength of the visible light corresponding to the nanopillar, the radial coordinate value of the nanopillar, and the focal length of the metasurface lens. Then, using Equation 1, the angle between the length direction of the orthographic projection of the nanopillar onto the transparent substrate in the metasurface lens and the reference direction can be calculated using the phase value obtained from Equation 2 and the known propagation phase value. It should be noted that "+" and "-" in Equation 1 correspond to "right-handed" and "left-handed" circularly polarized incident light, respectively. When the angle θ ranges from 0 to π, the modulated phase can cover the range of 0 to 2π.

[0065] In summary, this application provides a metasurface lens, which may include a transparent substrate and multiple sets of nanopillars. By configuring at least two nanopillars in each set of nanopillars in the metasurface lens to correspond to at least two wavelengths of visible light, and ensuring that the transmittance of each nanopillar for the corresponding wavelength of visible light is greater than the transmittance for other wavelengths, when visible light is incident on the metasurface lens, each nanopillar has a higher transmittance only for the corresponding wavelength of visible light, while having a lower transmittance for other wavelengths. This ensures that the energy of visible light of different wavelengths is higher only in the corresponding nanopillars and lower in other nanopillars, thereby effectively eliminating interference between different wavelengths of visible light and effectively eliminating chromatic aberration when visible light passes through the metasurface lens. Furthermore, since at least two wavelengths cover the visible light spectrum, the utilization efficiency of visible light is guaranteed. In addition, after integrating this metasurface lens into a camera module, the number of optical lenses in the camera module can be reduced, effectively reducing the size of the camera module. Furthermore, it can effectively reduce the size of terminal devices that integrate the camera module, while ensuring that the terminal device is lightweight.

[0066] This application also provides a camera module. Please refer to... Figure 9 , Figure 9 This is a schematic diagram of a camera module according to an embodiment of this application. The camera module may include a camera 001 and a metasurface lens 000. The metasurface lens 000 can be any of the metasurface lenses described above. The metasurface lens can eliminate chromatic aberration caused by incident light, resulting in better imaging performance when the camera images based on light emitted from the metasurface lens. For example, the camera typically includes a filter, a drive motor, and an image sensor (not shown in the figure). The filter is disposed between the metasurface lens and the image sensor, and the drive motor can drive the metasurface lens to move along the central axis of the camera for focusing.

[0067] It should be noted that the transparent substrate in the metasurface lens only supports the multiple nanopillars and does not regulate the light entering the metasurface lens. Therefore, the nanopillars in the metasurface lens can face or turn away from the camera relative to the transparent substrate.

[0068] This application also provides a terminal device, which can be any display device with camera function, such as a mobile phone, laptop, tablet, camera, or wearable device. The terminal device may include a display panel and a camera module. The camera module can be... Figure 9 The camera module shown is an example of a camera module that incorporates metasurface lenses. This ensures that the terminal device integrating the camera module is smaller in size and weight.

[0069] In this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The term "multiple" refers to two or more unless otherwise expressly defined.

[0070] The above description is merely an optional embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A metasurface lens, characterized in that, include: A transparent substrate (100) and multiple sets of nanopillars (200); The transparent substrate (100) has multiple lens regions (101) arranged in an array. Multiple sets of nanopillars (200) correspond one-to-one with multiple lens regions (101). Each set of nanopillars (200) contains at least two nanopillars, and each nanopillar in each set of nanopillars (200) is fixedly connected to the transparent substrate (100) within the corresponding lens region (101). In a group of nanopillars (200), at least two nanopillars correspond to at least two bands of visible light, and the transmittance of each nanopillar to the corresponding band of visible light is greater than the transmittance to other bands of visible light. The at least two bands cover the bands of visible light. In a group of nanopillars (200), each nanopillar has a transmittance of visible light in a corresponding wavelength band greater than or equal to a first threshold, and a transmittance of visible light in other wavelength bands less than or equal to a second threshold, wherein the first threshold is greater than the second threshold. Each group of nanopillars (200) contains four nanopillars arranged in two rows and two columns, and the shape formed by the center line connecting the orthographic projections of the four nanopillars (200) onto the transparent substrate (100) is a square. The number of visible light in at least two bands is four; the four nanopillars correspond one-to-one with the four visible light beams.

2. The metasurface lens according to claim 1, characterized in that, In a group of nanopillars (200), the area of ​​the orthographic projection of each nanopillar onto the transparent substrate (100) is different.

3. The metasurface lens according to claim 2, characterized in that, In any two different sets of nanopillars (200), the areas of the orthographic projections of the two nanopillars corresponding to the same visible light band on the transparent substrate (100) are the same.

4. The metasurface lens according to claim 3, characterized in that, The orthographic projection of each of the nanopillars (200) onto the transparent substrate (100) is rectangular; in any two different sets of nanopillars (200), the two nanopillars corresponding to the same visible light band have the same length and width on the orthographic projection onto the transparent substrate (100).

5. The metasurface lens according to claim 4, characterized in that, The length (L) of the orthographic projection of the nanopillar (200) onto the transparent substrate (100) ranges from 50 nanometers to 350 nanometers, and the width (W) of the orthographic projection of the nanopillar (200) onto the transparent substrate (100) ranges from 50 nanometers to 350 nanometers.

6. The metasurface lens according to any one of claims 1 to 5, characterized in that, The height (H) of each of the nanopillars (200) is the same.

7. The metasurface lens according to claim 6, characterized in that, The height (H) of the nanopillars ranges from 200 nanometers to 700 nanometers.

8. The metasurface lens according to any one of claims 1 to 5, characterized in that, At least some of the nanopillars (200) have different angles (ɵ) between the length direction of their orthographic projection onto the transparent substrate (100) and the reference direction. The reference direction is the direction of any coordinate axis in the target coordinate system of the metasurface lens, and the origin of the target coordinate system coincides with the center of the metasurface lens.

9. The metasurface lens according to claim 8, characterized in that, The angle (ɵ) between the length direction of the orthographic projection of the nanopillar (200) onto the transparent substrate (100) and the reference direction satisfies the following relationship: in, The angle between the length direction of the orthogonal projection of the nanopillar onto the transparent substrate and the reference direction; The propagation phase value represents the value obtained when visible light of each wavelength band passes through the corresponding nanopillar; This represents the phase of the visible light in the corresponding wavelength band after the nanopillars have been adjusted. This represents the radial coordinate value of the nanopillar on the metasurface lens; The center wavelength of visible light corresponding to the band of the nanopillar; This represents the focal length of the metasurface lens.

10. A camera module, characterized in that, include: The camera (001) and the metasurface lens (000) according to any one of claims 1 to 9.

Images