CN117062425B - Blocking and electromagnetic signal shielding protective film for laser eavesdropping - Google Patents
Blocking and electromagnetic signal shielding protective film for laser eavesdropping Download PDFInfo
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- CN117062425B CN117062425B CN202311170172.9A CN202311170172A CN117062425B CN 117062425 B CN117062425 B CN 117062425B CN 202311170172 A CN202311170172 A CN 202311170172A CN 117062425 B CN117062425 B CN 117062425B
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- 230000000903 blocking effect Effects 0.000 title claims abstract description 13
- 239000000463 material Substances 0.000 claims abstract description 37
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- 239000010410 layer Substances 0.000 claims description 16
- 239000000853 adhesive Substances 0.000 claims description 11
- 230000001070 adhesive effect Effects 0.000 claims description 11
- 239000011241 protective layer Substances 0.000 claims description 8
- 230000035699 permeability Effects 0.000 claims description 7
- 239000012790 adhesive layer Substances 0.000 claims description 5
- 229920000049 Carbon (fiber) Polymers 0.000 claims description 3
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- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims description 2
- 230000004224 protection Effects 0.000 abstract description 15
- 238000002834 transmittance Methods 0.000 abstract description 7
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- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 239000003292 glue Substances 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
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- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
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Classifications
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K9/00—Screening of apparatus or components against electric or magnetic fields
- H05K9/0073—Shielding materials
- H05K9/0081—Electromagnetic shielding materials, e.g. EMI, RFI shielding
- H05K9/0088—Electromagnetic shielding materials, e.g. EMI, RFI shielding comprising a plurality of shielding layers; combining different shielding material structure
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- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)
Abstract
The application discloses a laser eavesdropping blocking and electromagnetic signal shielding protective film. The protective film adopts a multi-layer shielding body, wherein the outer side of each shielding body adopts a high-conductivity material to enhance the reflection effect, and the inner side of the shielding body adopts a high-permeability material to increase the eddy current effect. The application can realize that the shielding blocking material has the electromagnetic shielding function and the laser eavesdropping protection function, and greatly improves the transmittance.
Description
Technical Field
The invention relates to the technical field of electromagnetic shielding, in particular to a protective film for blocking laser eavesdropping and shielding electromagnetic signals.
Background
The sound is generated by vibration and also causes vibration of surrounding articles. The laser eavesdropping technology is to emit a beam of laser invisible to human eyes, strike the laser on an object near a sound source, collect and analyze vibration of the object caused by the sound source, so that the sound is restored, and the purpose of eavesdropping by the laser is achieved.
The construction of the current secret place is still mainly focused on sound leakage and electromagnetic leakage, but the attention of the mode of laser interception is still obviously insufficient, and the importance of laser interception protection and electromagnetic shielding is emphasized again along with the release of new BMB standards. Although "laser tap disruptors" have existed for many years ago, the product has no protective effect on the current multitude of "window-through" laser taps, which has been gradually eliminated. Aiming at the leakage mode of window-penetrating type laser eavesdropping, a brand new protection product is urgently needed.
Disclosure of Invention
Based on the above, the embodiment of the application provides the shielding and blocking and electromagnetic signal shielding protective film for laser interception, which can realize that the shielding and blocking material has the electromagnetic shielding function and the laser interception protective function at the same time, thereby greatly improving the transmittance.
The application provides a laser eavesdropping blocking and electromagnetic signal shielding protective film, which comprises the following components:
a multi-layer shield wherein the outer side of each layer of shield is made of a high conductivity material to enhance reflection and the inner side of the shield is made of a high permeability material to increase eddy current effect.
Optionally, the high conductivity material comprises at least a metal and a carbon fiber material.
Optionally, the high permeability material comprises at least a ferromagnetic material.
Optionally, the protective film further comprises a protective layer, which is located on the outer side of the shielding body and is used for protecting the shielding body from damage and environmental influences.
Optionally, the protective layer is made of wear-resistant, corrosion-resistant and high-temperature-resistant materials.
Optionally, the protective film further comprises a backing adhesive layer for adhering and securing the multilayer shield to an object or surface to be protected.
Optionally, the backsize layer includes an adhesive and a backing; the adhesive is used for bonding different surfaces; the backing is used to support the adhesive.
Optionally, the surface of the shielding body is smooth, and no gap exists.
Optionally, the protective film is used for blocking 780-1800nm full-band eavesdropping invasion laser.
Optionally, the protective film is made of high and low temperature resistant materials, and can be used in an environment of-55 to 85 ℃.
In the technical scheme provided by the embodiment of the application, the outer side of each layer of shielding body adopts a high-conductivity material to enhance the reflection effect, and the inner side of the shielding body adopts a high-permeability material to enhance the eddy current effect.
The technical scheme provided by the embodiment of the application has the beneficial effects that the shielding blocking material at least has an electromagnetic shielding function and a laser eavesdropping protection function, and the transmittance is greatly improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. It will be apparent to those skilled in the art from this disclosure that the drawings described below are merely exemplary and that other embodiments may be derived from the drawings provided without undue effort.
Fig. 1 is a schematic view of a protection effect of a laser interception protection film according to an embodiment of the present application;
fig. 2 is a schematic diagram of waveforms before and after protection according to an embodiment of the present application.
Detailed Description
The present application will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present application more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the application.
In the description of the present invention, the terms "comprises," "comprising," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements but may include other steps or elements not expressly listed but inherent to such process, method, article, or apparatus or steps or elements added based on further optimization of the inventive concept.
Preventing sound leakage, optical leakage and electromagnetic leakage is one of the important tasks in the security field. In recent years, the self-research technology breaks various restrictions, and in the individual fields, the technology has become an industrial army from the laggard chasers. The upgrading iteration of the technology also brings new challenges to the security work.
Traditional means such as interception and steal, electromagnetic leakage and steal secret are upgraded along with technology upgrading, and detection distance, sensitivity and hazard degree are greatly improved. The novel technology represented by the laser eavesdropping technology becomes the latest generation of eavesdropping technology, and has the characteristics of no awareness, no evidence obtaining, long eavesdropping distance and strong sound effect. To date, new means of steal have been able to defeat most of the protection means earlier. For new means of steal, new protection products are needed.
The construction of the current secret place is still mainly focused on sound leakage and electromagnetic leakage, but the attention of the mode of laser interception is still obviously insufficient, and the importance of laser interception protection and electromagnetic shielding is emphasized again along with the release of new BMB standards. Although "laser tap disruptors" have existed for many years ago, the product has no protective effect on the current multitude of "window-through" laser taps, which has been gradually eliminated. Aiming at the leakage mode of window-penetrating type laser eavesdropping, a brand new protection product is urgently needed.
Electromagnetic leakage refers to the outward diffusion of stray (parasitic) electromagnetic energy of an electronic device through a wire or space. Any electromagnetic information device in operation, such as a computer, a printer, a facsimile, a telephone, etc., has electromagnetic leakage to varying degrees, which is an inexhaustible electromagnetic phenomenon. These leaks "entrain" information handled by the device, which constitutes so-called electromagnetic radiation information leaks, abbreviated electromagnetic leaks. Electromagnetic signal leakage is stopped, and an electromagnetic shielding solution is needed.
The sound is generated by vibration and also causes vibration of surrounding articles. The laser eavesdropping technology is to emit a beam of laser invisible to human eyes, strike the laser on an object near a sound source, collect and analyze vibration of the object caused by the sound source, so that the sound is restored, and the purpose of eavesdropping by the laser is achieved.
Specifically, please refer to fig. 1, which illustrates an effect diagram of a protective film for blocking laser interception and shielding electromagnetic signals according to an embodiment of the present application, the protective film may include:
a multi-layer shield wherein the outer side of each layer of shield is made of a high conductivity material to enhance reflection and the inner side of the shield is made of a high permeability material to increase eddy current effect.
The shielding body is a core part of the protective film and is used for restraining the influence of a high-frequency electromagnetic field. It may be a multilayer structure, the outer layer is usually made of a material with high electrical conductivity to enhance reflection, and the inner layer is made of a material with high magnetic permeability to increase eddy current effect. This way the field strength of the disturbing field can be attenuated by multiple reflections and eddy current effects. The principle of the electromagnetic shielding mainly comprises that the electromagnetic shielding is mainly used for suppressing the influence of a high-frequency electromagnetic field, so that an interference field forms vortex in the shielding body and generates reflection on the interface between the shielding body and a protected space, thereby greatly weakening the field intensity value of the interference field in the protected space and achieving the shielding effect. Sometimes, in order to enhance the shielding effect, a multi-layer shielding body may be used, wherein the outer layer is generally made of a material with high conductivity so as to enhance the reflection effect, and the inner layer is made of a material with high magnetic conductivity so as to enhance the eddy current effect. If a cavity or gap appears on the shielding body, the shielding effect will be directly reduced, and the higher the frequency is, the more remarkable the phenomenon is.
In particular, the high-conductivity material has good conductivity and can effectively reflect electromagnetic waves. Common high conductivity materials include metals (e.g., copper, aluminum), carbon fibers, and the like. These materials can provide low impedance paths, reflect electromagnetic waves on their surfaces, and reduce the likelihood of electromagnetic wave penetration. The high permeability material has good absorption and guiding effects on the magnetic field, and can enable the magnetic field lines to generate eddy currents therein, so that the propagation of electromagnetic waves is weakened. Common high permeability materials include ferromagnetic materials such as iron, nickel, cobalt, and the like. These materials are capable of absorbing magnetic field energy and converting it into thermal energy, thereby reducing the field strength of electromagnetic waves.
When a high frequency electromagnetic field is applied to the shield, eddy currents are formed in the shield. Eddy currents are circulating currents caused by magnetic induction, which may create additional electromagnetic fields to interact with the original electromagnetic field.
When a reflection is generated at the interface between the disturbing field and the shielding, the energy of the disturbing field will be reflected back, thereby reducing the influence of the disturbing field in the protected space. Enhancement of the reflection effect can be achieved by using a material with high electrical conductivity as the outer layer of the shield.
In order to ensure the shielding effect, it is necessary to avoid cavities or gaps in the shielding. Because any cavity or gap directly reduces the shielding effect, an interference field can pass through the cavity or gap and enter the protected space. Therefore, special care is required to avoid the presence of cavities and crevices in the manufacture and installation of the protective film.
In an alternative embodiment of the application, the protective film further comprises a protective layer, which is located outside the shielding body for protecting the shielding body from damage and environmental influences. The protective layer is made of wear-resistant, corrosion-resistant and high-temperature-resistant materials.
The protective film also includes a backsize layer for adhering and securing the multilayer shield to an object or surface to be protected. The back adhesive layer comprises an adhesive and a back lining; the adhesive is a special material, has good adhesion performance and can provide reliable adhesion between different surfaces. It may be a liquid glue, adhesive or hot melt glue, etc. The backing is a substrate for supporting the adhesive and plays a role in supporting and protecting the adhesive in the manufacturing process of the protective film. The backing may be a plastic film, a polyester film, or the like.
A schematic diagram of waveforms before and after protection in an embodiment of the present application is shown in fig. 2. It can be seen that the main functions of the protective film provided by the application include:
1. The industry is leading the 'photoelectric fusion' laser interception protection, and the shielding blocking material has the electromagnetic shielding function and the laser interception protection function at the same time, so that the transmittance is greatly improved;
2. The appearance is consistent with the appearance of a common film, and the special equipment is not adopted to check the difference, so that the risk that a secret thief recognizes a specific room by observing the appearance of the film is effectively avoided;
3. The damage of electromagnetic waves to human bodies, in particular to the damage of high-power electromagnetic waves to human bodies, is effectively prevented;
4. electromagnetic wave leakage is effectively prevented, and safety of secret electronic equipment is protected;
5. the full-band interception of the intrusion laser of 780-1800nm is blocked, and the interception of the intrusion laser is stopped.
The product features include:
1. 100% of domestic brands are adopted;
2. the high-precision vacuum magnetic control production process has strong product uniformity;
3. no grid structure is adopted, interference fringes are not generated, and dizziness is avoided;
4. the definition is high, the light transmission is high, and the ultraviolet protection function can be realized;
5. the protective layer, the back adhesive layer and the special process are adopted to prevent oxidation and resist temperature impact;
6. the shielding effectiveness is high, and the highest shielding effectiveness reaches 40 dB;
7. high and low temperature resistance and normal use at-55-85 ℃ for a long time.
The specific parameters of use of the protective film according to the application are also given:
Visible light transmittance: not less than 0.48;
electromagnetic shielding effectiveness: 30MHz-1.5GHz is more than or equal to 30dB;
electromagnetic shielding effectiveness: 1.5GHz-10GHz is more than or equal to 31dB;
900-1800nm band eavesdropping laser transmittance: less than or equal to 0.02;
ultraviolet transmittance: less than or equal to 0.01;
visible light reflectance: less than or equal to 0.08;
The use temperature is as follows: -55-85 ℃;
packaging specification: the width is 1.52m, the length is customized, and the coiled material is packaged.
The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.
The above examples illustrate only a few embodiments of the application, which are described in detail and are not to be construed as limiting the scope of the claims. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the application, which are all within the scope of the application. Accordingly, the scope of protection of the present application is to be determined by the appended claims.
Claims (1)
1. The protective film is characterized by comprising a plurality of layers of shielding bodies, wherein the outer side of each layer of shielding body adopts a high-conductivity material to enhance the reflection effect, and the inner side of the shielding body adopts a high-permeability material to enhance the eddy current effect;
the high-conductivity material at least comprises a metal and a carbon fiber material;
the high permeability material comprises at least a ferromagnetic material;
The protective film also comprises a protective layer, wherein the protective layer is positioned on the outer side of the shielding body and is used for protecting the shielding body from damage and environmental influence;
The protective layer is made of wear-resistant, corrosion-resistant and high-temperature-resistant materials;
the protective film also comprises a back adhesive layer, which is used for bonding and fixing the multi-layer shielding body on an object or surface to be protected;
The back adhesive layer comprises an adhesive and a back lining; the adhesive is used for bonding different surfaces; the backing is used for supporting the adhesive;
The protective film is used for blocking 780-1800nm full-band eavesdropping invasion laser;
the protective film can be used in an environment of-55 to 85 ℃.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311170172.9A CN117062425B (en) | 2023-09-11 | 2023-09-11 | Blocking and electromagnetic signal shielding protective film for laser eavesdropping |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311170172.9A CN117062425B (en) | 2023-09-11 | 2023-09-11 | Blocking and electromagnetic signal shielding protective film for laser eavesdropping |
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| Publication Number | Publication Date |
|---|---|
| CN117062425A CN117062425A (en) | 2023-11-14 |
| CN117062425B true CN117062425B (en) | 2024-06-04 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311170172.9A Active CN117062425B (en) | 2023-09-11 | 2023-09-11 | Blocking and electromagnetic signal shielding protective film for laser eavesdropping |
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| Country | Link |
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| CN (1) | CN117062425B (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103171184A (en) * | 2011-12-20 | 2013-06-26 | 北京有色金属研究总院 | Low frequency strong magnetic field shield material |
| CN105307465A (en) * | 2015-11-17 | 2016-02-03 | 华东师范大学 | Electromagnetic anti-interference composite layer structure and device employing same |
| CN107849401A (en) * | 2015-06-24 | 2018-03-27 | 诺凡赛尔公司 | Pressure sensitive adhesive film and its use for protecting surfaces |
| CN111031774A (en) * | 2019-12-24 | 2020-04-17 | 苏州威斯东山电子技术有限公司 | Electromagnetic shielding material of ferrite and metal composite lamination |
| KR20210080941A (en) * | 2019-12-23 | 2021-07-01 | 주식회사 지민 | Masking tape and manufacturing method thereof |
| CN113637418A (en) * | 2021-08-23 | 2021-11-12 | 三千新材料(苏州)有限公司 | Electromagnetic shielding laser eavesdropping blocking two-in-one film and preparation method thereof |
| CN217438039U (en) * | 2022-02-24 | 2022-09-16 | 安方高科电磁安全技术(北京)有限公司 | Glass, window and door with infrared blocking and electromagnetic shielding functions |
-
2023
- 2023-09-11 CN CN202311170172.9A patent/CN117062425B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103171184A (en) * | 2011-12-20 | 2013-06-26 | 北京有色金属研究总院 | Low frequency strong magnetic field shield material |
| CN107849401A (en) * | 2015-06-24 | 2018-03-27 | 诺凡赛尔公司 | Pressure sensitive adhesive film and its use for protecting surfaces |
| CN105307465A (en) * | 2015-11-17 | 2016-02-03 | 华东师范大学 | Electromagnetic anti-interference composite layer structure and device employing same |
| KR20210080941A (en) * | 2019-12-23 | 2021-07-01 | 주식회사 지민 | Masking tape and manufacturing method thereof |
| CN111031774A (en) * | 2019-12-24 | 2020-04-17 | 苏州威斯东山电子技术有限公司 | Electromagnetic shielding material of ferrite and metal composite lamination |
| CN113637418A (en) * | 2021-08-23 | 2021-11-12 | 三千新材料(苏州)有限公司 | Electromagnetic shielding laser eavesdropping blocking two-in-one film and preparation method thereof |
| CN217438039U (en) * | 2022-02-24 | 2022-09-16 | 安方高科电磁安全技术(北京)有限公司 | Glass, window and door with infrared blocking and electromagnetic shielding functions |
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| CN117062425A (en) | 2023-11-14 |
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