US-20260129993-A1 - IMAGE SENSOR, CAMERA MODULE, ELECTRONIC DEVICE, AND DISPLAY SYSTEM

US20260129993A1US 20260129993 A1US20260129993 A1US 20260129993A1US-20260129993-A1

Abstract

This application provide an image sensor, a camera module, an electronic device, and a display system. The image sensor includes a metasurface layer and an optical-to-electrical conversion layer that are disposed in a stacked manner. The optical-to-electrical conversion layer is configured to convert light transmitted through the metasurface layer into an electrical signal. The metasurface layer has a first micro-nano structure layer, the first micro-nano structure layer includes a plurality of microstructure arrays, each microstructure array includes a plurality of structure units arranged in an array, and structures of structure units of at least two microstructure arrays are different. The optical-to-electrical conversion layer has a plurality of photosensitive areas, and the plurality of photosensitive areas are in a one-to-one correspondence with a plurality of structure units at the metasurface layer.

Inventors

Youming Zhang
Pengfei Luo
Youquan LUO
Hui Ren

Assignees

HUAWEI TECHNOLOGIES CO., LTD.

Dates

Publication Date: 20260507
Application Date: 20251229

Claims (20)

1 . An image sensor, comprising a metasurface layer and an optical-to-electrical conversion layer that are disposed in a stacked manner along an optical axis of the image sensor, wherein the optical-to-electrical conversion layer is configured to convert light transmitted through the metasurface layer into an electrical signal, wherein the metasurface layer has a first micro-nano structure layer, the first micro-nano structure layer comprises a plurality of microstructure arrays, each microstructure array comprises a plurality of structure units arranged in an array, and structures of structure units of at least two microstructure arrays of the plurality of microstructure arrays are different; and the optical-to-electrical conversion layer has a plurality of photosensitive areas, and the plurality of photosensitive areas are in a one-to-one correspondence with a plurality of structure units at the metasurface layer.
2 . The image sensor according to claim 1 , wherein structures of structure units of any two microstructure arrays of the plurality of microstructure arrays are different.
3 . The image sensor according to claim 1 , wherein center-to-center spacings of structure units of at least two microstructure arrays of the plurality of microstructure arrays are different; and in a direction perpendicular to a direction in which the metasurface layer and the optical-to-electrical conversion layer are stacked, the center-to-center spacing is a spacing between a center of the structure unit and a center of a corresponding photosensitive area.
4 . The image sensor according to claim 3 , wherein the plurality of microstructure arrays comprise a first microstructure array and a plurality of annular second microstructure arrays, and the plurality of second microstructure arrays sequentially surround the first microstructure array; and in a radial direction of the second microstructure array and in a direction from the first microstructure array to the second microstructure array, center-to-center spacings of the structure units of the plurality of microstructure arrays gradually increase.
5 . The image sensor according to claim 1 , wherein in a same microstructure array of the plurality of microstructure arrays , center-to-center spacings of any two structure units are the same.
6 . The image sensor according to claim 1 , wherein each structure unit comprises a plurality of substructures, structures of at least two substructures in the plurality of substructures are different, and each substructure comprises a plurality of columnar structures; and each photosensitive area comprises a plurality of subareas, the plurality of subareas of each photosensitive area are in a one-to-one correspondence with the plurality of substructures of the corresponding structure unit, and each subarea corresponds to light in one color and is configured to convert the light in the corresponding color into an electrical signal.
7 . The image sensor according to claim 6 , wherein the image sensor further comprises a color filter layer, the color filter layer is located between the metasurface layer and the optical-to-electrical conversion layer, the color filter layer comprises a plurality of color filter units arranged in an array, and each color filter unit corresponds to one structure unit and one photosensitive area; and each color filter unit comprises a plurality of color filter areas, each color filter area corresponds to one substructure and one subarea, and symmetry of each color filter area is the same as symmetry of the corresponding substructure.
8 . The image sensor according to claim 7 , wherein an arrangement manner of the plurality of color filter areas of each color filter unit is any one of the following arrangement manners: red, green, green, and blue; red, yellow, yellow, and blue; red, green, blue, and white; red, yellow, blue, and white; and cyan, yellow, yellow, and magenta.
9 . The image sensor according to claim 6 , wherein the image sensor further comprises a second micro-nano structure layer, the second micro-nano structure layer is disposed between the metasurface layer and the optical-to-electrical conversion layer, the second micro-nano structure layer comprises a plurality of micro-nano unit structures, and each micro-nano unit structure comprises a plurality of micro-nano structures; and each micro-nano unit structure corresponds to one structure unit and one photosensitive area, and each micro-nano unit structure is configured to transmit light transmitted through the corresponding structure unit to the corresponding photosensitive area.
10 . The image sensor according to claim 1 , wherein each structure unit comprises at least two types of media having different refractive indexes, and at least one type of medium in the at least two types of media having different refractive indexes is configured to form a columnar structure.
11 . The image sensor according to claim 1 , wherein the metasurface layer further comprises a substrate layer, and the substrate layer is located between the first micro-nano structure layer and the optical-to-electrical conversion layer and is connected to the first micro-nano structure layer.
12 . The image sensor according to claim 11 , wherein the substrate layer comprises a planarization layer and a spacing layer that are disposed in a stacked manner, the spacing layer is located between the first micro-nano structure layer and the planarization layer, and the planarization layer is configured to connect to one of a color filter layer and a second micro-nano structure layer.
13 . The image sensor according to claim 1 , wherein the image sensor further comprises an anti-reflection layer, and the anti-reflection layer covers a surface of the first micro-nano structure layer.
14 . A camera module, comprising a lens and an image sensor, wherein the image sensor comprises a metasurface layer and an optical-to-electrical conversion layer that are disposed in a stacked manner along an optical axis of the camera module, wherein the optical-to-electrical conversion layer is configured to convert light transmitted through the metasurface layer into an electrical signal, wherein the metasurface layer has a first micro-nano structure layer, the first micro-nano structure layer comprises a plurality of microstructure arrays, each microstructure array comprises a plurality of structure units arranged in an array, and structures of structure units of at least two microstructure arrays of the plurality of microstructure arrays are different; and the optical-to-electrical conversion layer has a plurality of photosensitive areas, and the plurality of photosensitive areas are in a one-to-one correspondence with a plurality of structure units at the metasurface layer, wherein a light exit side of the lens faces the metasurface layer of the image sensor.
15 . The camera module according to claim 14 , wherein structures of structure units of any two microstructure arrays of the plurality of microstructure arrays are different.
16 . The camera module according to claim 14 , wherein center-to-center spacings of structure units of at least two microstructure arrays of the plurality of microstructure arrays are different; and in a direction perpendicular to a direction in which the metasurface layer and the optical-to-electrical conversion layer are stacked, the center-to-center spacing is a spacing between a center of the structure unit and a center of a corresponding photosensitive area.
17 . The camera module according to claim 16 , wherein the plurality of microstructure arrays comprise a first microstructure array and a plurality of annular second microstructure arrays, and the plurality of second microstructure arrays sequentially surround the first microstructure array; and in a radial direction of the second microstructure array and in a direction from the first microstructure array to the second microstructure array, center-to-center spacings of the structure units of the plurality of microstructure arrays gradually increase.
18 . An electronic device, comprising a processor and a camera module, wherein the camera module comprises a lens and an image sensor, wherein the image sensor comprises a metasurface layer and an optical-to-electrical conversion layer that are disposed in a stacked manner along an optical axis of the camera module, wherein the optical-to-electrical conversion layer is configured to convert light transmitted through the metasurface layer into an electrical signal, wherein the metasurface layer has a first micro-nano structure layer, the first micro-nano structure layer comprises a plurality of microstructure arrays, each microstructure array comprises a plurality of structure units arranged in an array, and structures of structure units of at least two microstructure arrays of the plurality of microstructure arrays are different; and the optical-to-electrical conversion layer has a plurality of photosensitive areas, and the plurality of photosensitive areas are in a one-to-one correspondence with a plurality of structure units at the metasurface layer, wherein a light exit side of the lens faces the metasurface layer of the image sensor, wherein the processor is electrically connected to the image sensor of the camera module and is configured to process an electrical signal output by the image sensor.
19 . The electronic device according to claim 18 , wherein structures of structure units of any two microstructure arrays of the plurality of microstructure arrays are different.
20 . The electronic device according to claim 18 , wherein center-to-center spacings of structure units of at least two microstructure arrays are different; and in a direction perpendicular to a direction in which the metasurface layer and the optical-to-electrical conversion layer are stacked, the center-to-center spacing is a spacing between a center of the structure unit and a center of a corresponding photosensitive area.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation of International Application No. PCT/CN2023/105084, filed on June 30, 2023, the disclosure of which is hereby incorporated by reference in its entirety. TECHNICAL FIELD This application relates to the field of optical imaging technologies, and in particular, to an image sensor, a camera module, an electronic device, and a display system. BACKGROUND An image sensor is a device that can convert an optical image into an electrical signal, and is widely used in electronic devices such as a mobile phone, a digital camera, a tablet computer, and a camera. For example, the image sensor is used in the digital camera. The digital camera projects an optical image onto the image sensor by using a lens assembly. The image sensor converts an optical signal of the image into an analog electrical signal and inputs the analog electrical signal into an electrical signal processor of the digital camera. The electrical signal processor converts the analog electrical signal into a digital signal, performs data processing on the digital signal, and outputs a photo. In a related technology, the image sensor obtains color information of an image by using a color filter, and the image sensor obtains light intensity information of the image by using an optical-to-electrical conversion element, and obtains a color image based on the light intensity information and the color information. However, an image obtained by an existing image sensor has a problem of low image quality. For example, the image has defects such as uneven luminance and uneven colors. Therefore, techniques for improving image quality of an image obtained by an image sensor becomes an urgent problem to be resolved. SUMMARY OF EXAMPLE EMBODIMENTS Embodiments of this disclosure provide an image sensor, a camera module, an electronic device, and a display system, to improve image quality. A first aspect of this disclosure provides an image sensor, including a metasurface layer and an optical-to-electrical conversion layer that are disposed in a stacked manner, where the optical-to-electrical conversion layer is configured to convert light transmitted through the metasurface layer into an electrical signal. The metasurface layer has a first micro-nano structure layer, the first micro-nano structure layer includes a plurality of microstructure arrays, each microstructure array includes a plurality of structure units arranged in an array, and structures of structure units of at least two microstructure arrays are different. The optical-to-electrical conversion layer has a plurality of photosensitive areas, and the plurality of photosensitive areas are in a one-to-one correspondence with a plurality of structure units at the metasurface layer. The first micro-nano structure layer in the image sensor provided in this embodiment of this disclosure includes a plurality of microstructure arrays, and structures of structure units of at least two microstructure arrays are different, so that the at least two microstructure arrays respond to incident light differently, that is, the structure units of the at least two microstructure arrays have different refractive indexes or transmittances for the incident light. Therefore, even if amounts of transmitted light are different, amounts of light received by photosensitive areas corresponding to structure units of different structures can be the same, that is, light intensity sensed by the photosensitive areas is the same. Therefore, structures of structure units in microstructure arrays at different positions are changed, so that light intensity sensed by corresponding photosensitive areas can be changed, light intensity of a corresponding part in an image meets a requirement, and light intensity of a part of or the whole image meets the requirement, thereby improving image quality. For example, light intensity of a local area or all areas of the image is controlled, so that light intensity of the entire image can be the same, thereby avoiding problems such as uneven luminance and/or uneven colors. In addition, because the structures of the structure units of the at least two microstructure arrays are different, the metasurface layer has structure units of a plurality of structures, and the at least two microstructure arrays work at different angles. In this way, a working angle range of the metasurface layer may be increased, to improve image quality. For example, the working angle range of the metasurface layer is large, so that it can be ensured that both a luminance gain and a color gain at an edge of the image sensor are positive gains, thereby improving the image quality. In a possible implementation, structures of structure units of any two microstructure arrays are different. Structures of structure units of any two microstructure arrays in the image sensor provided in this embodiment of this disclosure are different, so that structure units of differe