Wave absorber

Abstract

The utility model provides a wave absorber which is formed by arranging at least one wave absorbing unit in an array mode, each wave absorbing unit comprises a resonance absorbing layer, a first substrate layer, a middle dielectric layer, a second substrate layer and a plane absorbing layer which are sequentially stacked, each resonance absorbing layer comprises resonance patterns, each resonance pattern comprises a square ring pattern and a square block pattern, and the square ring pattern and the square block pattern are arranged in a staggered mode. The square block patterns are arranged in the square ring pattern in an array mode, and the square block patterns are connected into a whole through one or more corners of the square block patterns. Through the above implementation mode, the resonance pattern comprises the plurality of mutually connected square block patterns arranged in the square ring pattern, and the plurality of square block patterns are connected into a whole through one corner or a plurality of corners, so that the area of a single square block pattern is not influenced, and the square block patterns are utilized to absorb electromagnetic waves to the maximum extent; and the plurality of square patterns are mutually connected together, so that a relatively good resonance effect can be achieved, and the absorption effect of the resonance pattern is further improved.

Description

Technical Field

[0001] The present application relates to the technical field of electromagnetic wave absorption, and in particular to a wave absorbing body. Background Art

[0002] With the continuous development of modern communication technology and the widespread application of electromagnetic waves as information transmission carriers in the electronics and communications fields, the impact of electromagnetic waves on the information exchange between various electronic systems has become increasingly significant. Absorbers have become an effective means of reducing electromagnetic waves because they can absorb electromagnetic energy incident on their surfaces and convert it into heat or other forms of energy.

[0003] However, although existing absorbers have multiple absorbing functions such as single-frequency absorption and broadband absorption, there is still a lack of research on absorbers for absorbing low-frequency electromagnetic waves, especially those in the Bluetooth band. Summary of the Invention

[0004] The main purpose of this application is to provide an absorber to solve the above-mentioned technical problems existing in the prior art.

[0005] To solve the above problems, the present application provides an absorber, which is composed of at least one array of absorbing units. The absorbing units include a resonant absorption layer, a first substrate layer, an intermediate dielectric layer, a second substrate layer and a planar absorption layer stacked in sequence. The resonant absorption layer includes a resonant pattern, and the resonant pattern includes a square ring pattern and a square pattern. A plurality of square pattern arrays are arranged in the square ring pattern, and the plurality of square patterns are connected as a whole through one or more corners of each.

[0006] In some embodiments, the projections of the geometric centers of the square ring pattern and the plurality of square patterns on the absorbing unit are located at the same point.

[0007] In some embodiments, the geometric centers of the square ring pattern and the plurality of square patterns and the geometric center of the absorbing unit are located on the central axis of the absorbing unit.

[0008] In some embodiments, the square ring pattern and the plurality of square block patterns are axially symmetric and centrally symmetric patterns, and a resonant pattern formed by the square ring pattern and the plurality of square block patterns is axially symmetric and centrally symmetric patterns.

[0009] In some embodiments, the square pattern includes a first square and four second squares, and four right angles of a first square are respectively connected to a right angle of a second square.

[0010] In some embodiments, the side length a of the first block is 8 mm-12 mm.

[0011] In some embodiments, the side length b of the second block is 7 mm-11 mm.

[0012] In some embodiments, the square resistance of the resonant absorption layer is 16Ω / square-20Ω / square, and the square resistance of the planar absorption layer is 16Ω / square-36Ω / square.

[0013] In some embodiments, the resonant absorption layer further includes four resistors, the square ring pattern has mounting notches corresponding to the number of resistors, the mounting notches are respectively arranged in the middle of one side of the square ring pattern, one resistor is arranged in one mounting notch, and the four resistors are arranged in the same clockwise direction.

[0014] In some embodiments, the resistance of the resistor is 100Ω-900Ω.

[0015] Compared to the prior art, the absorber provided by the present application comprises at least one array of absorbing units. The absorbing units include a resonant absorption layer, a first substrate layer, an intermediate dielectric layer, a second substrate layer, and a planar absorption layer stacked in sequence. The resonant absorption layer includes a resonant pattern, which includes a square ring pattern and a square block pattern. Multiple square block patterns are arrayed within the square ring pattern, and the multiple square blocks are connected to form a whole through one or more corners. According to the above embodiment, the resonant pattern includes multiple interconnected square patterns arranged within the square ring pattern, and the multiple square patterns are connected to form a whole through one or more corners. This does not affect the area of ​​a single square pattern, thereby maximizing the use of the square pattern to absorb electromagnetic waves. Furthermore, the interconnected multiple square patterns can also produce a good resonance effect, thereby improving the absorption effect of the resonant pattern. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0017] Figure 1 This is a schematic structural diagram from a first perspective of an embodiment of the absorber provided by the present application;

[0018] Figure 2 yes Figure 1 A schematic structural diagram of the absorber from a second perspective is shown;

[0019] Figure 3 yes Figure 2 A graph showing the relationship between the side length of the first square and the absorptivity;

[0020] Figure 4 yes Figure 2A graph showing the relationship between the side length of the second square and the absorptivity is shown;

[0021] Figure 5 yes Figure 1 The relationship between the square resistance and absorptivity of the resonant absorption layer shown;

[0022] Figure 6 yes Figure 1 The relationship between the sheet resistance and absorptivity of the planar absorption layer shown;

[0023] Figure 7 yes Figure 2 The resistance and absorptivity of the resistor shown is plotted;

[0024] Figure 8 yes Figure 1 The relationship between the incident angle and absorptivity of the absorbing unit and the electromagnetic wave shown;

[0025] Figure 9 yes Figure 1 The relationship between the bending radius and absorptivity of the absorbing unit is shown.

[0026] Reference numerals: absorbing unit 100 ; resonant absorption layer 110 ; square ring pattern 111 ; square pattern 112 ; first square 1121 ; second square 1122 ; resistor 114 ; mounting notch 113 ; first substrate layer 120 ; intermediate dielectric layer 130 ; second substrate layer 140 ; ​​planar absorption layer 150 . DETAILED DESCRIPTION

[0027] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0029] In the description of the embodiments of the present application, technical terms such as "first" and "second" are only used to distinguish different objects and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features.

[0030] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0031] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0032] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0033] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0034] In the description of the embodiments of the present application, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connected," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; internal connections between two components or interactions between two components. Those skilled in the art can understand the specific meanings of the above terms in the embodiments of the present application based on specific circumstances.

[0035] With the continuous development of modern communication technology and the widespread application of electromagnetic waves as information transmission carriers in the electronics and communications fields, the impact of electromagnetic waves on information exchange between various electronic systems has become increasingly significant. Absorbers, which absorb electromagnetic energy incident on their surfaces and convert it into heat or other forms of energy, have become an effective means of reducing electromagnetic wave loss. However, while existing absorbers have various absorbing capabilities, such as single-frequency and broadband absorption, research on absorbers specifically targeting low-frequency electromagnetic waves, particularly those in the Bluetooth band, is lacking.

[0036] In order to solve the related technical problems, the present application provides a wave absorber. Figure 1 and Figure 2 , Figure 1 This is a schematic structural diagram of a first perspective of an embodiment of the absorber provided by the present application. Figure 2 yes Figure 1 A schematic structural diagram of the absorber from a second perspective is shown.

[0037] The absorber is composed of at least one absorbing unit 100 arranged in an array. The absorbing unit 100 includes a resonant absorption layer 110, a first substrate layer 120, an intermediate dielectric layer 130, a second substrate layer 140 and a planar absorption layer 150 stacked in sequence. The resonant absorption layer 110 includes a resonant pattern, which includes a square ring pattern 111 and a square pattern 112. A plurality of square patterns 112 are arranged in an array within the square ring pattern 111. The plurality of square patterns 112 are connected as a whole through one or more corners of each.

[0038] The resonant absorption layer 110 is disposed on the upper surface of the first substrate layer 120 and can be formed through an etching process. The resonant absorption layer 110 can be made of a transparent, flexible, and electromagnetic wave-absorbing material, such as indium tin oxide (ITO) or antimony tin oxide (ANTO). This absorbs electromagnetic waves, thereby reducing their impact on other electronic devices and systems. The intermediate dielectric layer 130 is disposed on the lower surface of the first substrate layer 120 and can also absorb electromagnetic waves, increasing the absorption rate within the Bluetooth frequency band and broadening the absorption frequency range. The intermediate dielectric layer 130 can be made of a transparent, flexible material, such as polyethylene terephthalate (PET) or polymethyl methacrylate (PMMA). The second substrate layer 140 is disposed on the lower surface of the intermediate dielectric layer 130 and can absorb electromagnetic waves. It also serves as the substrate for the planar absorption layer 150, which is disposed on the lower surface of the second substrate layer 140. The planar absorption layer 150 can be flat, thereby improving its absorption rate. The planar absorption layer 150 can be made of a transparent, flexible, and electromagnetic wave-absorbing material, such as ITO or ANTO.

[0039] The resonant absorption layer 110 includes a resonant pattern, which is conducive to the absorption of electromagnetic waves. The resonant pattern includes a square ring pattern 111 and a square pattern 112. The square ring pattern 111 can be a ring-shaped square with a width, that is, the inner edge of the square ring pattern 111 is offset relative to the outer edge, and the offset distance is the width of the square ring pattern 111, which can be 2.5 mm. The square pattern 112 can be composed of a plurality of square structures. The square ring pattern 111 and the square pattern 112 can absorb electromagnetic waves in different frequency ranges to broaden the absorption frequency range of electromagnetic waves and improve the absorption rate of electromagnetic waves. Multiple square patterns 112 are arranged in an array inside the square ring pattern 111, and multiple schemes are connected as a whole through one or more corners of each. Both the square ring pattern 111 and the square pattern 112 can absorb electromagnetic waves. The square pattern 112 is arranged inside the square ring pattern 111, and the multiple square patterns 112 are connected to each other, which is conducive to resonance between the multiple square patterns 112. The resonance of the resonant pattern is the key to the absorber absorbing electromagnetic waves. Therefore, the setting of the square patterns 112 being connected to each other can improve the absorption rate of electromagnetic waves.

[0040] According to the above embodiment, the absorber includes multiple absorbing units 100, each of which can be a cube with a square cross-section, forming a regular shape. The absorbing unit 100 includes a resonant absorption layer 110, a first substrate layer 120, an intermediate dielectric layer 130, a second substrate layer 140, and a planar absorption layer 150 stacked in sequence. The first substrate layer 120, the intermediate dielectric layer 130, the second substrate layer 140, and the planar absorption layer 150 can be square, giving the absorbing unit 100 a regular structure, thereby facilitating the design of the absorber. The resonant pattern includes multiple interconnected square patterns 112 disposed within a square ring pattern 111. The multiple square patterns 112 are connected together at one or more corners to form a single entity, without affecting the area of ​​a single square pattern 112. This maximizes the utilization of the square patterns 112 for absorbing electromagnetic waves. Furthermore, the interconnected multiple square patterns 112 can also achieve a good resonant effect, thereby enhancing the absorption effect of the resonant pattern.

[0041] In some embodiments, the geometric centers of the square ring pattern 111 and the plurality of square patterns 112 are projected onto the same point on the absorbing unit 100. The thicknesses of the square ring pattern 111 and the square pattern 112 can be equal, and the geometric center of the plurality of square patterns 112, considered as a whole, is located at the same point as the geometric center of the square ring pattern 111. In other words, the distance between the entirety of the square pattern 112 and the four sides of the square ring pattern 111 is equal. This allows the resonance generated by each square pattern 112 to be the same as that of the square ring pattern 111, allowing the absorbing unit 100 to more closely absorb electromagnetic waves at certain frequencies, thereby improving the absorption rate of electromagnetic waves.

[0042] In some embodiments, the geometric centers of the square ring pattern 111 and the plurality of square patterns 112 and the geometric center of the absorbing unit 100 are located on the central axis of the absorbing unit 100. That is, the geometric center of the resonant pattern formed by the square ring pattern 111 and the square pattern 112 and the geometric center of the entire absorbing unit 100 are located on the central axis. The four sides of the square ring pattern 111 of the resonant pattern are equidistant from their respective corresponding sides of the absorbing unit 100. In other words, the four sides of the square ring pattern 111 are equidistant from their respective corresponding four sides of the first substrate layer 120, so that the overall resonant pattern forms a good resonance effect, thereby improving the absorption rate of electromagnetic waves.

[0043] In some embodiments, the square ring pattern 111 and the multiple square patterns 112 are axially and centrally symmetric, and the resonant pattern formed by the square ring pattern 111 and the multiple square patterns 112 is axially and centrally symmetric. The square ring pattern 111, the individual square patterns 112, and the entirety of the individual square patterns 112 are both axially and centrally symmetric, so that the overall resonant pattern is both axially and centrally symmetric. Electromagnetic waves emitted into the resonant pattern are polarized, while a symmetrical resonant pattern is insensitive to electromagnetic waves, thereby reducing reflection of electromagnetic waves from the resonant pattern surface, allowing the electromagnetic waves to enter and be absorbed by the resonant pattern, thereby improving the absorption of electromagnetic waves.

[0044] In some embodiments, the square pattern 112 may include one first square 1121 and four second squares 1122. The four right angles of one first square 1121 are each connected to a right angle of one second square 1122. The square pattern 112 may be five, namely one first square 1121 and four second squares 1122. The radial dimensions of the second squares 1122 are larger than the radial dimensions of the first square 1121, and the second squares 1122 are connected to a corresponding corner of the first square 1121 via one of their respective corners. This allows the first square 1121 and the second square 1122 to achieve a good resonance effect. Furthermore, the five square patterns 112 allow the first square 1121 and the second square 1122 to form a strong resonance, thereby broadening the frequency range of electromagnetic wave absorption and improving the electromagnetic wave absorption rate.

[0045] See also Figure 3 , Figure 3 yes Figure 2 The relationship between the side length of the first square and the absorption rate is shown.

[0046] In some embodiments, the side length a of the first block 1121 is 8 mm to 12 mm. The side length a of the first block 1121, when in the range of 8 mm to 12 mm, allows the absorber to absorb electromagnetic waves within the Bluetooth frequency band, with an absorption rate greater than 90% within this range. Specifically, the side length of the first block 1121 can be 10 mm. This 10 mm side length effectively improves the absorption rate of electromagnetic waves while maintaining a wide frequency range for electromagnetic wave absorption.

[0047] See also Figure 4 , Figure 4 yes Figure 2 The relationship between the side length of the second square and the absorption rate is shown.

[0048] In some embodiments, the side length b of the second block 1122 is 7 mm to 11 mm. The side length b of the second block 1122 is in the range of 7 mm to 11 mm. As the side length of the second block 1122 gradually increases, the absorber's absorption rate of electromagnetic waves gradually decreases, and the absorption frequency of electromagnetic waves gradually shifts to a lower frequency range. Specifically, when the side length of the second block 1122 is 9 mm, the absorber has both a high electromagnetic wave absorption rate and a wide electromagnetic wave absorption frequency range.

[0049] See also Figure 5 and Figure 6 , Figure 5 yes Figure 1 The relationship between the square resistance and absorptivity of the resonant absorption layer is shown. Figure 6 yes Figure 1 The relationship between the sheet resistance and absorptivity of the planar absorption layer is shown.

[0050] In some embodiments, the square resistance of the resonant absorption layer 110 is between 16Ω / square and 20Ω / square, and the square resistance of the planar absorption layer 150 is between 16Ω / square and 36Ω / square. When the square resistance of the resonant absorption layer 110 is within the range of 16Ω / square and 20Ω / square, and the square resistance of the planar absorption layer 150 is within the range of 16Ω / square and 36Ω / square, the resonant absorption layer 110 and the planar absorption layer 150 of the absorber can absorb electromagnetic waves within the Bluetooth frequency band, with excellent absorption effects. Specifically, when the square resistance of the resonant absorption layer 110 is 18Ω / square and the square resistance of the planar absorption layer 150 is 26Ω / square, the absorber has both a high electromagnetic wave absorption rate and a wide electromagnetic wave absorption frequency range.

[0051] In some embodiments, the resonant absorption layer 110 further includes four resistors 114. The square ring pattern 111 has mounting notches 113 corresponding to the number of resistors 114. The mounting notches 113 are located in the middle of each side of the square ring pattern 111, with one resistor 114 located in each mounting notch 113. The four resistors 114 are oriented in the same clockwise direction. Each side of the square ring pattern 111 has a mounting notch 113 in the middle for mounting a resistor 114. Resistors 114 can improve electromagnetic wave absorption. Furthermore, the resistors 114 are symmetrically distributed along the four sides of the square ring pattern 111, and the resistors 114 are oriented in the same clockwise direction, either clockwise or counterclockwise. The resistors 114 oriented in the same clockwise direction can guide electromagnetic waves within the square ring pattern 111, allowing them to circulate in either a clockwise or counterclockwise direction, thereby improving electromagnetic wave absorption. The structure of the resistor includes a cylindrical structure and a conical structure. A circular side surface of the cylindrical structure is connected to a circular bottom surface of the conical structure. The direction from the cylindrical structure to the conical structure is the direction of the resistor.

[0052] See also Figure 7 , Figure 7 yes Figure 2 The resistance vs. absorption rate graph of the resistor shown.

[0053] In some embodiments, the resistance of the resistor 114 is 100Ω-900Ω. The resistance of the resistor 114 being 100Ω-900Ω can enable the absorber to better absorb electromagnetic waves.

[0054] Therefore, the absorber can achieve an absorption rate of more than 90% for electromagnetic waves within a frequency range of 1.7 GHz to 4.4 GHz, and a relative absorption bandwidth of 113%.

[0055] See also Figure 8 and Figure 9 , Figure 8 yes Figure 1 The relationship between the incident angle and absorptivity of the absorbing unit and the electromagnetic wave is shown. Figure 9 yes Figure 1 The relationship between the bending radius and absorptivity of the absorbing unit is shown.

[0056] In one embodiment, the incident angle θ between the absorber and the electromagnetic wave can be between 0° and 45°. As the incident angle of the electromagnetic wave increases, the absorber's absorption bandwidth of greater than 90% gradually narrows. Within the range of incident angles less than 45°, its absorption rate remains above 80%, and the absorber has good angular stability. The bending radius of the absorber after bending is r, and the range of r can be 0mm to 18mm. It can be understood that the bending radius is the distance from the lower surface of the absorbing unit 100 to the center of the circle after bending. The higher the degree of bending, the smaller the bending radius. As the degree of bending increases, that is, the bending radius decreases, the absorber's absorption frequency range narrows, but it can still achieve more than 90% absorption of electromagnetic waves within the Bluetooth communication frequency band, and the overall absorption performance remains in a good state.

[0057] In summary, the absorber includes multiple absorbing units 100, which can be rectangular parallelepipeds with square cross-sections, forming a regular shape. The absorbing units 100 include a resonant absorption layer 110, a first substrate layer 120, an intermediate dielectric layer 130, a second substrate layer 140, and a planar absorption layer 150 stacked in sequence. The first substrate layer 120, the intermediate dielectric layer 130, the second substrate layer 140, and the planar absorption layer 150 can be square in shape, giving the absorbing unit 100 a regular structure, thereby facilitating the design of the absorber. The resonant pattern includes multiple interconnected square patterns 112 disposed within a square ring pattern 111. The multiple square patterns 112 are connected together at one or more corners, forming a single entity without affecting the area of ​​a single square pattern 112, thereby maximizing the utilization of the square patterns 112 for absorbing electromagnetic waves. Furthermore, the interconnected multiple square patterns 112 also exhibit a good resonant effect, thereby enhancing the absorption effect of the resonant pattern.

[0058] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A wave absorbing body, characterized in that: The absorber is composed of at least one array of absorbing units, and the absorbing unit includes a resonant absorption layer, a first substrate layer, an intermediate dielectric layer, a second substrate layer and a planar absorption layer stacked in sequence. The resonant absorption layer includes a resonant pattern, and the resonant pattern includes a square ring pattern and a square pattern. A plurality of the square patterns are arrayed in the square ring pattern, and the plurality of the square patterns are connected as a whole through one or more corners of each.

2. The absorber according to claim 1, wherein: The projections of the geometric centers of the square ring pattern and the plurality of square patterns as a whole on the wave absorbing unit are located at the same point.

3. The absorber according to claim 2, wherein: The geometric centers of the square ring pattern and the plurality of square patterns and the geometric center of the absorbing unit are located on the central axis of the absorbing unit.

4. The absorber according to claim 1, wherein: The square ring pattern and the plurality of square block patterns are axially symmetrical and centrally symmetrical patterns, and the resonant pattern formed by the square ring pattern and the plurality of square block patterns is axially symmetrical and centrally symmetrical patterns.

5. The absorber according to claim 4, characterized in that: The square pattern includes a first square and four second squares, and the four right angles of one of the first squares are respectively connected to a right angle of one of the second squares.

6. The absorber according to claim 5, characterized in that: The side length a of the first block is 8 mm to 12 mm.

7. The absorber according to claim 5, characterized in that: The side length b of the second block is 7 mm to 11 mm.

8. The absorber according to claim 1, wherein: The square resistance of the resonant absorption layer is 16Ω / square-20Ω / square, and the square resistance of the planar absorption layer is 16Ω / square-36Ω / square.

9. The absorber according to claim 1, wherein: The resonant absorption layer also includes four resistors. The square ring pattern has mounting notches corresponding to the number of the resistors. The mounting notches are respectively arranged in the middle of one side of the square ring pattern. One resistor is arranged in one mounting notch, and the four resistors are arranged in the same clockwise direction.

10. The absorber according to claim 9, characterized in that: The resistance of the resistor is 100Ω-900Ω.

Images