CN-122003787-A - Radio wave absorber and radio wave absorbing system provided with same

Abstract

The radio wave absorbing device includes a patch electrode, a counter electrode facing the patch electrode and made of a material different from that of the patch electrode, and a liquid crystal layer between the patch electrode and the counter electrode. The other radio wave absorbing device includes a 1 st patch electrode, a 2 nd patch electrode which can be controlled independently of the 1 st patch electrode, a counter electrode which is opposed to the 1 st patch electrode and the 2 nd patch electrode, and a liquid crystal layer between the 1 st patch electrode and the counter electrode and between the 2 nd patch electrode and the counter electrode, wherein the 1 st relative permittivity of the liquid crystal layer sandwiched by the 1 st patch electrode and the counter electrode is different from the 2 nd relative permittivity of the liquid crystal layer sandwiched by the 2 nd patch electrode and the counter electrode.

Inventors

• MATSUNAGA KAZUMI
• Ichiro Okayama
• OKITA MITSUTAKA
• SUZUKI DAIICHI

Assignees

• 株式会社日本显示器

Dates

Publication Date

20260508

Application Date

20241018

Priority Date

20231024

Claims (16)

1. 1. An electric wave absorbing apparatus, comprising: A patch electrode; a counter electrode facing the patch electrode and made of a material different from that of the patch electrode, and And a liquid crystal layer between the patch electrode and the counter electrode.
2. 2. The electric wave absorbing apparatus according to claim 1, wherein, The conductivity of the material constituting the patch electrode is different from the conductivity of the material constituting the counter electrode.
3. 3. The electric wave absorbing apparatus according to claim 1, wherein, The ratio of the conductivity of the material constituting the patch electrode to the conductivity of the material constituting the counter electrode is 10 times or more.
4. 4. The electric wave absorbing apparatus according to claim 1, wherein, When the patch electrode is made of a metal material, the counter electrode is made of a transparent conductive material, In the case where the patch electrode is made of a transparent conductive material, the counter electrode is made of a metal material.
5. 5. An electric wave absorbing apparatus, comprising: 1 st patch electrode; a2 nd patch electrode capable of being controlled independently of the 1 st patch electrode; A counter electrode facing the 1 st patch electrode and the 2 nd patch electrode, and A liquid crystal layer between the 1 st patch electrode and the counter electrode and between the 2 nd patch electrode and the counter electrode, The 1 st relative permittivity of the liquid crystal layer sandwiched by the 1 st patch electrode and the counter electrode is different from the 2 nd relative permittivity of the liquid crystal layer sandwiched by the 2 nd patch electrode and the counter electrode.
6. 6. The electric wave absorbing apparatus according to claim 5, wherein, The 1 st patch electrode is made of a material different from that of the counter electrode, The material constituting the 2 nd patch electrode is different from the material constituting the counter electrode.
7. 7. The electric wave absorbing apparatus according to claim 5, wherein, The ratio of the conductivity of the material constituting the patch electrode to the conductivity of the material constituting the counter electrode is 10 times or more.
8. 8. The electric wave absorbing apparatus according to claim 5, wherein, When the patch electrode is made of a metal material, the counter electrode is made of a transparent conductive material, In the case where the patch electrode is made of a transparent conductive material, the counter electrode is made of a metal material.
9. 9. The radio wave absorbing device according to any one of claims 1 to 8, wherein, Further comprises a substrate which is arranged on the side of the liquid crystal layer, on which the electric wave is incident relative to the electric wave absorbing device, The thickness of the substrate is different from lambda/4 with respect to the wavelength lambda of the radio wave incident on the radio wave absorbing device.
10. 10. The radio wave absorbing device according to any one of claims 1 to 8, wherein, The thickness of the liquid crystal layer is 10 μm to 40 μm.
11. 11. The radio wave absorbing device according to any one of claims 1 to 4, wherein, The patch electrode comprises a1 st patch electrode and a2 nd patch electrode, The size of the 1 st patch electrode is different from the size of the 2 nd patch electrode.
12. 12. The radio wave absorbing device according to any one of claims 5 to 8, wherein, The size of the 1 st patch electrode is different from the size of the 2 nd patch electrode.
13. 13. An electric wave absorbing system, comprising: the radio wave absorbing device according to any one of claims 1 to 4, and A control device for controlling the voltages supplied to the patch electrode and the counter electrode, The control device controls the voltages supplied to the patch electrode and the counter electrode to change the amount of absorption of the radio wave having an arbitrary frequency by the radio wave absorbing device.
14. 14. The electric wave absorbing system according to claim 13, wherein, The control device receives a set value related to the frequency of the radio wave absorbed by the radio wave absorbing device, and controls the voltages supplied to the patch electrode and the counter electrode based on the set value.
15. 15. An electric wave absorbing system, comprising: a radio wave absorbing device according to any one of claims 5 to 8, and A control device for controlling voltages supplied to the 1 st patch electrode, the 2 nd patch electrode, and the counter electrode, The control device controls the voltages supplied to the 1 st patch electrode, the 2 nd patch electrode, and the counter electrode to change the amount of absorption of the radio wave having an arbitrary frequency by the radio wave absorbing device.
16. 16. The electric wave absorbing system according to claim 15, wherein, The control device receives a set value related to the frequency of the radio wave absorbed by the radio wave absorbing device, and controls the voltages supplied to the patch electrode and the counter electrode based on the set value.

Description

Radio wave absorber and radio wave absorbing system provided with same Technical Field One embodiment of the present invention relates to a radio wave absorber capable of absorbing an incident radio wave and a radio wave absorbing system including the same. Background In recent years, devices using a high frequency of 10GHz to 100GHz have been widely used. With this, problems such as radio wave crosstalk and congestion occur between a plurality of high-frequency devices. In order to solve such a problem, there is an increasing demand for a radio wave absorbing device that reduces radio wave crosstalk or congestion. Prior art literature Patent literature Patent document 1 Japanese patent laid-open No. 2022-047398 Disclosure of Invention Conventional wave absorbing devices are designed to absorb a wave having a specific frequency. Therefore, after the radio wave absorber is provided, the frequency of the radio wave absorbed by the radio wave absorber cannot be changed. Further, the conventional radio wave absorbing device cannot switch between a state of absorbing radio waves and a state of reflecting radio waves. An object of one embodiment of the present invention is to provide a radio wave absorbing device capable of adjusting radio wave absorbing performance. A radio wave absorbing device according to one embodiment of the present invention includes a patch electrode, a counter electrode facing the patch electrode and made of a material different from that of the patch electrode, and a liquid crystal layer between the patch electrode and the counter electrode. A radio wave absorbing device according to one embodiment of the present invention includes a1 st patch electrode, a 2 nd patch electrode that can be controlled independently of the 1 st patch electrode, a counter electrode that faces the 1 st patch electrode and the 2 nd patch electrode, and a liquid crystal layer between the 1 st patch electrode and the counter electrode and between the 2 nd patch electrode and the counter electrode, wherein the 1 st relative permittivity of the liquid crystal layer sandwiched between the 1 st patch electrode and the counter electrode is different from the 2 nd relative permittivity of the liquid crystal layer sandwiched between the 2 nd patch electrode and the counter electrode. The radio wave absorbing system according to one embodiment of the present invention includes the radio wave absorbing device, and a control device that controls voltages supplied to the patch electrode and the counter electrode, wherein the control device changes an amount of absorption of radio waves having an arbitrary frequency by the radio wave absorbing device by controlling the voltages supplied to the patch electrode and the counter electrode. The radio wave absorbing system according to one embodiment of the present invention includes the radio wave absorbing device described above, and a control device that controls voltages supplied to the 1 st patch electrode, the 2 nd patch electrode, and the counter electrode, wherein the control device changes an amount of absorption of radio waves having an arbitrary frequency by the radio wave absorbing device by controlling voltages supplied to the 1 st patch electrode, the 2 nd patch electrode, and the counter electrode. Drawings Fig. 1 is a schematic cross-sectional view and a functional block diagram showing a radio wave absorbing system according to an embodiment of the present invention. Fig. 2 is a schematic cross-sectional view of a radio wave absorber according to an embodiment of the present invention. Fig. 3A is a plan view of an absorber plate cell (cell structure) used in the radio wave absorber according to the embodiment of the present invention. Fig. 3B is a cross-sectional structure of an absorber plate cell used in the radio wave absorber according to the embodiment of the present invention. Fig. 4A is a diagram showing a state in which a control voltage is not applied between the patch electrode and the counter electrode in the absorber plate cell used in the radio wave absorber according to the embodiment of the present invention. Fig. 4B is a diagram showing a state in which a control voltage is applied between the patch electrode and the ground electrode in an absorber plate cell used in the radio wave absorber according to the embodiment of the present invention. Fig. 5 is a simulation result showing a relationship between a voltage supplied to the patch electrode and the ground electrode and a frequency band in which a radio wave is absorbed in the radio wave absorbing device according to the embodiment of the present invention. Fig. 6 is a simulation result showing the frequency bands of the absorption of the radio wave in the radio wave absorber according to the embodiment of the present invention. Fig. 7 is a simulation result showing the relationship between the electrical conductivities of the patch electrode and the ground electrode and the radio wave absorpt