US-12620684-B2 - Spatial filter, driving method thereof and electronic device

Abstract

A spatial filter, a driving method thereof and an electronic device are provided, and belong to the field of wireless communication technology. The spatial filter of the present disclosure includes at least one filter structure; wherein each filter structure includes a first substrate, a second substrate opposite to the first substrate, and a dielectric layer between the first substrate and the second substrate; wherein the first substrate includes a first dielectric substrate and at least one first electrode on a side of the first dielectric substrate close to the dielectric layer; the second substrate includes a second dielectric substrate and at least one second electrode on a side of the second dielectric substrate close to the dielectric layer; and the at least one first electrode intersects with the at least one second electrode, which defines at least one resonant unit configured to filter an electromagnetic wave.

Inventors

• Feng Wang
• Long Wang
• Feng Qu
• Biqi LI

Assignees

• Beijing Boe Technology Development Co., Ltd.
• BOE TECHNOLOGY GROUP CO., LTD.

Dates

Publication Date

20260505

Application Date

20220719

Claims (20)

1. 1 . A spatial filter, comprising at least one layer of filter structure; wherein the filter structure comprises a first substrate, a second substrate opposite to the first substrate, and a dielectric layer between the first substrate and the second substrate; wherein the first substrate comprises a first dielectric substrate and at least one first electrode on a side of the first dielectric substrate close to the dielectric layer; the second substrate comprises a second dielectric substrate and at least one second electrode on a side of the second dielectric substrate close to the dielectric layer; and the at least one first electrode intersects with the at least one second electrode, which defines at least one resonant unit configured to filter an electromagnetic wave; wherein the resonant unit further comprises a first opening in the first electrode, and/or a second opening in the second electrode; when the resonant unit comprises the first opening in the first electrode, and orthographic projections of the first opening and the second electrode on the first dielectric substrate intersect with each other; and when the resonant unit comprises the second opening in the second electrode, and orthographic projections of the second opening and the first electrode on the first dielectric substrate intersect with each other.
2. 2 . The spatial filter of claim 1 , wherein the at least one first electrode comprises a plurality of first electrodes and the at least one second electrode comprises a plurality of second electrodes; the plurality of first electrodes extend along a first direction and are arranged side by side along a second direction; the plurality of second electrodes extend along the second direction, and are arranged side by side along the first direction; and the plurality of first electrodes intersect with the plurality of second electrodes, which defines a plurality of resonant units arranged in an array.
3. 3 . The spatial filter of claim 2 , wherein the plurality of first electrodes have a same interval between every two adjacent first electrodes, and/or the plurality of second electrodes have a same interval between every two adjacent second electrodes.
4. 4 . The spatial filter of claim 2 , wherein the plurality of first electrodes have a same size and/or the plurality of second electrodes have a same size.
5. 5 . The spatial filter of claim 2 , wherein an interval between every two adjacent first electrodes is a first interval, and an interval between every two adjacent second electrodes is a second interval; and the first interval and the second interval are equal to each other.
6. 6 . The spatial filter of claim 1 , wherein widths of the plurality of first electrodes and of the plurality of second electrodes are equal to each other.
7. 7 . The spatial filter of claim 1 , wherein the dielectric layer comprises a liquid crystal layer.
8. 8 . The spatial filter of claim 1 , wherein extending directions of the first electrode and of the second electrode in the filter structure are orthogonal to each other.
9. 9 . The spatial filter of claim 1 , wherein the first electrode has a thickness in a range of 2 μm to 5 μm and/or the second electrode has a thickness in a range of 2 μm to 5 μm.
10. 10 . The spatial filter of claim 1 , wherein the dielectric layer has a thickness in a range of 5 μm to 200 μm.
11. 11 . A method for driving the spatial filter of claim 1 , comprising: changing a dielectric constant of the dielectric layer by applying voltages to the at least one first electrode and the at least one second electrode, to change a resonance frequency of the at least one resonant unit to filter the electromagnetic wave.
12. 12 . The method of claim 11 , wherein the at least one first electrode comprises a plurality of first electrodes and the at least one second electrode comprises a plurality of second electrodes; and the applying the voltages to the at least one first electrode and the at least one second electrode comprises: applying the same voltage to the plurality of first electrodes and applying different voltages to at least some of the plurality of second electrodes.
13. 13 . The method of claim 11 , wherein the at least one first electrode comprises a plurality of first electrodes and the at least one second electrode comprises a plurality of second electrodes; and the applying the voltages to the at least one first electrode and the at least one second electrode comprises: applying different voltages to at least some of the plurality of first electrodes, and applying different voltages to at least some of the plurality of second electrodes.
14. 14 . An electronic device, comprising the spatial filter of claim 1 .
15. 15 . The spatial filter of claim 1 , wherein the at least one layer of filter structure comprises a plurality of layers of filter structures, which are stacked together.
16. 16 . A spatial filter, comprising at least one layer of filter structure; wherein the filter structure comprises a first substrate, a second substrate opposite to the first substrate, and a dielectric layer between the first substrate and the second substrate; wherein the first substrate comprises a first dielectric substrate and at least one first electrode on a side of the first dielectric substrate close to the dielectric layer; the second substrate comprises a second dielectric substrate and at least one second electrode on a side of the second dielectric substrate close to the dielectric layer; and the at least one first electrode intersects with the at least one second electrode, which defines at least one resonant unit configured to filter an electromagnetic wave, wherein the at least one layer of filter structure comprises a plurality of layers of filter structures, which are stacked together.
17. 17 . The spatial filter of claim 16 , wherein the first dielectric substrate of one of two adjacent layers of filter structures is used as the second dielectric substrate of the other one of the two adjacent layers of filter structures.
18. 18 . The spatial filter of claim 16 , wherein the first dielectric substrate of one of two adjacent layers of filter structures and the second dielectric substrate of the other one of the two adjacent layers of filter structures are adhered together by a first adhesive layer.
19. 19 . The spatial filter of claim 16 , wherein orthographic projections of the resonant units in the plurality of layers of filter structures on one of the first dielectric substrates do not overlap with each other.
20. 20 . A spatial filter, comprising at least one layer of filter structure; wherein the filter structure comprises a first substrate, a second substrate opposite to the first substrate, and a dielectric layer between the first substrate and the second substrate; wherein the first substrate comprises a first dielectric substrate and at least one first electrode on a side of the first dielectric substrate close to the dielectric layer; the second substrate comprises a second dielectric substrate and at least one second electrode on a side of the second dielectric substrate close to the dielectric layer; and the at least one first electrode intersects with the at least one second electrode, which defines at least one resonant unit configured to filter an electromagnetic wave; wherein the dielectric layer comprises a liquid crystal layer; and the spatial filter further comprises a first alignment layer on a side of a layer, where the at least one first electrode is located, close to the liquid crystal layer; and a second alignment layer on a side of a layer, where the at least one second electrode is located, close to the liquid crystal layer.

Description

TECHNICAL FIELD The present disclosure relates to the field of wireless communication technology, and in particular to a spatial filter, a method for driving a spatial filter and an electronic device. BACKGROUND A spatial filter has a filtering characteristic changing with a frequency when filtering an electromagnetic wave incident from a space. The spatial filter may be considered as a frequency selective surface, i.e., FSS. The frequency selective surface is a two-dimensional periodic structure including periodic apertures, patches, or a combination of the apertures and the patches. The frequency selective surface is generally divided into having band pass type or band stop type filtering characteristics. The band pass type frequency selective surface generally may allow an electromagnetic wave in a certain specific frequency band to completely pass through the frequency selective surface, and may completely reflect or absorb an electromagnetic wave outside the frequency band; while the band stop type frequency selective surface generally absorbs or reflects an electromagnetic wave in a certain frequency band, and an unexpected electromagnetic wave in other frequency bands may normally pass through the frequency selective surface. The filtering characteristics of the conventional FSS are mainly based on a resonance mechanism of the FSS, with an operating wavelength depending on a period length between units or a resonant frequency of the unit itself. The spatial filter or the frequency selective surface has a great practical application value. For example, with the rapid development of the mobile internet, a low frequency communication resource is almost completely utilized, so that an electromagnetic interference, especially frequency multiplication interference, between different communication systems is gradually intensified, which has seriously affected the normal communication. The spatial filter may be applied to a housing of an electronic device for preventing the electromagnetic interference. For another example, the frequency selective surface can reduce a radar cross section (RCS) of an aircraft, or form a common aperture multiband nested antenna, or be applied to an antenna housing of a base station for assisting the antenna filtering. Generally, the spatial filter has a structure with a fixed frequency, and once a manufacturing process is completed, the achievable filter response characteristic or operating frequency band is fixed, which greatly limits the practical application of the spatial filter. The adjustable spatial filter generally has difficulty in controlling individual units, and mainly has difficulty in arranging control lines when the number of units in the spatial filter array is increased. Therefore, the current spatial filters are based on integral tuning and do not use a way of controlling the individual units. SUMMARY The present disclosure is directed to solve at least one of the technical problems in the prior art, and provides a spatial filter, a method for driving a spatial filter, and an electronic device. In a first aspect, an embodiment of the present disclosure provides a spatial filter, including at least one filter structure; wherein each filter structure includes a first substrate, a second substrate opposite to the first substrate, and a dielectric layer between the first substrate and the second substrate; wherein the first substrate includes a first dielectric substrate and at least one first electrode on a side of the first dielectric substrate close to the dielectric layer; the second substrate includes a second dielectric substrate and at least one second electrode on a side of the second dielectric substrate close to the dielectric layer; and the at least one first electrode intersects with the at least one second electrode, which defines at least one resonant unit configured to filter an electromagnetic wave. In some embodiments, the at least one first electrode includes a plurality of first electrodes and the at least one second electrode includes a plurality of second electrodes; the plurality of first electrodes extend along a first direction and are arranged side by side along a second direction; the plurality of second electrodes extend along the second direction, and are arranged side by side along the first direction; and the plurality of first electrodes intersect with the plurality of second electrodes, which defines a plurality of resonant units arranged in an array. In some embodiments, intervals between every adjacent first electrodes are the same, and/or intervals between every adjacent second electrodes are the same. In some embodiments, the plurality of first electrodes have a same size and/or the plurality of second electrodes have a same size. In some embodiments, an interval between any two adjacent first electrodes is a first interval, and an interval between any two adjacent second electrodes is a second interval; and the first interval