Classifications

• • 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
  • H05K9/0094—Shielding materials being light-transmitting, e.g. transparent, translucent
  • H05K9/0096—Shielding materials being light-transmitting, e.g. transparent, translucent for television displays, e.g. plasma display panel
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q15/00—Devices for reflection, refraction, diffraction or polarisation of waves radiated from an antenna, e.g. quasi-optical devices
  • H01Q15/14—Reflecting surfaces; Equivalent structures

Definitions

• CH-PS No. ⁇ 3 391 and EP-PS No. 0 010 711 and No. 0 010 712 describe the production and use of certain metallized textiles as materials for shielding against electromagnetic radiation. These materials can be used both for shielding an object or a person from electromagnetic radiation from the environment and also for preventing the escape of electromagnetic radiation from an object.
• Glare the reflection of incident light and the "flickering" of the screens lead to health problems for the operating personnel, such as eye strain, headaches, etc.
• This special problem can be solved by opening black openings colored or painted textiles, of which several assortments are commercially available, are arranged between the screen or the optical display device and the viewer, or by applying special anti-reflection coatings to the screen.
• Electrostatic fields generated by the screens or other optical display devices lead to health problems of the operating personnel as described above under 1 and can occur in certain sensitive areas, e.g. also cause operational problems when handling electronic solid-state components.
• This problem can be solved by arranging grounded metallic fabrics or knitted fabrics between the screen or the other optical display device and the viewer.
• Such materials are commercially available.
• Electromagnetic radiation from the environment can enter the optical display device through the screen and disrupt or damage the information contained within the system.
• This problem can be solved by arranging woven or knitted fabrics made of metals or metallized polymers between the display device and the viewer. If such materials are suitable grounded, they can of course also solve the problem of static electricity. They are also commercially available.
• the screen can emit electromagnetic radiation into the environment, which can lead to disturbance or damage to surrounding facilities, health problems for operating personnel and impairment of safety . Accessibility of the information carried by the radiation from the system results in a distance from the system.
• This problem can be solved by arranging woven or knitted textiles made of metals or metallized polymers, as mentioned above under 3, between the display device and the viewer in such a way that an effective one is formed from the housing of the device Faraday cage is created.
• the present invention relates to textiles which combine the solution of all four problems described above in one material. It has been shown that
• Woven, knitted or non-woven textiles with openings based on monofilaments made of natural or synthetic polymers, graphite or metal fibers or mixtures thereof provide glare protection, a shield against static electricity and a highly effective shield against electromagnetic radiation if they a) have matt surfaces with roughnesses between one eighth and five times the wavelength of visible light, b) shield electromagnetic flat wave radiation of more than 20 dB between 10 kHz and 30 GHz and c) have a DC surface resistance of less than 2000 ohms per square area.
• the textiles according to the invention are useful for shielding screens or other optical display devices, analog or digital displays, windows, fans, etc. Because of their optical properties, certain types are also useful as radiation absorption elements in solar collectors.
• the geometry of the holes in the textiles should be such that they are one to three times the size of the individual picture elements (pixels) in order to minimize the "flickering".
• Example 1 shows an electron microscopic image of the material produced according to Example 1 (magnified 200 times);
• Example 2 shows an electron microscopic image of the material produced according to Example 1 (magnified 1000 times);
• Example 3 shows an electron microscopic image of the material produced according to Example 1 (magnified 5000 times);
• Fig. an electron microscopic image of the material produced according to Example 1 (magnified 10,000 times);
• FIG. 6 shows the device used to measure the shielding attenuation effect in the range from 18 to 26 GHz
• FIG. 7 shows the device used to measure the shielding attenuation effect in the range from 10 MHz to 18 GHz.
• the textile material 6 to be examined is a low-noise amplifier
• variable attenuator 0 to 110 dB 3 a coaxial connector
• the device according to FIG. 7 either has a coaxial connector (3) or a waveguide flange (4) or horn antennas (5).
• a high-precision polyester monofilament fabric (Monolen 58 T from Zürcher Beuteltuchfabrik AG, Rüschlikon, Switzerland) was procured and activated using methods well known to the person skilled in the art, electrolessly coated with a nickel-phosphorus alloy and then electroplated with nickel, to manufacture the patentee's commercial product PMO 300.
• Zinc chloride 38.0 g / liter sodium thiocyanate 19.5 g / liter which was produced with deionized water using nickel anodes and cathode current densities of 1 to 2.5 A7dm at temperatures of 12 to 30 ° C for 1 to 3 minutes with provided with a galvanic black coating.
• the resulting material has a highly matt surface of black color.
• Electron microscopic images (see FIGS. 1 to 4) showed a microstructure consisting of cylinders of 0.2 to 0.5 ⁇ m in width and 0.5 to 2.0 ⁇ m in length, which are combined to form clumps , whose dimensions in length, width and height are between 0.5 and 10 ⁇ ⁇ m.
• the wavelengths of visible light are between 0.4 and 0.7 ⁇ m; it is therefore clear that this surface morphology causes very effective scattering and multiple internal reflections, which leads to extremely good glare protection properties.
• the geometry of the fabric belonged to the following
• the DC surface resistance of the material was measured using the device shown in FIG. 5 and was 140 to 180 m ££ per square area.
• the shielding attenuation effect of the material against electromagnetic radiation was measured in a coaxial energy line under far field conditions by means of the devices shown in FIGS. 6 and 7 and was greater than 50 dB in the frequency range from 10 MHz to 26 GHz.
• the shielding attenuation effect for the E-field was measured according to the MIL-STD-285 standard and was greater than 50 dB in the frequency range from 250 kHz to 400 MHz.
• the material could be cut easily and using a glue or Velcro tapes (Velcro conclusion) or by means of similar fastening methods or also after mounting on a suitable plastic or metal support in front of an optical display device.
• the resulting matt screen could be grounded to the chassis of the display device using wires that were soldered or conductively glued to the textile material, or using conductive adhesive strips or other methods well known to the person skilled in the art.
• a true shielded optical see ad device as for example in the TEMPEST regulations of the US military authorities are required to obtain a it is necessary to ensure that a kontinuierli ⁇ che electrical connection with low conductivity rule zwi ⁇ the extent of the textile screen and the electrically conductive housing of the display device exists.
• the material can also be used in the form of a laminate with suitable plastics or glasses.
• Thread diameter approx. 38 ⁇ m
• Hole dimensions approx. 40 ⁇ m
• Thread diameter approx. Jim
• the commercial product ZBF 58 T (a high-precision polyester monofilament fabric) from Zürcher Beuteltuchfabrik AG was procured and activated using processes well known to those skilled in the art and electrolessly plated with nickel.
• the resulting copper-coated material was then treated under the conditions described in Example 1 in the black sulfamate-based nickel bath described there.
• Example 5 was repeated using a high precision fabric made of monofilaments made of stainless steel with 200 meshes per 25.4 ⁇ m (Fila diameter 40 ⁇ m, hole diameter 90 ⁇ m), from which the rinsing with concentrated nitric acid was omitted.
• a copper mesh (DIN 2.0120, W.730, D.320) from G. Bopp and Co. AG was procured, degreased, quickly rinsed with nitric acid and then with deionized water and then plated as in Example 1 in the black sulfamate-based nickel bath .
• Example 7 was repeated using the black sulfate-based nickel bath of Example 2.
• Example 7 was repeated using the black chrome bath of Example 3.

Landscapes

• Physics & Mathematics (AREA)
• Engineering & Computer Science (AREA)
• Electromagnetism (AREA)
• Plasma & Fusion (AREA)
• Microelectronics & Electronic Packaging (AREA)
• Woven Fabrics (AREA)
• Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=4231002

Family Applications (1)

Country Status (5)

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Family Cites Families (4)

• 1986
  • 1986-05-28 AU AU58152/86A patent/AU5815286A/en not_active Abandoned
  • 1986-05-28 WO PCT/CH1986/000071 patent/WO1986007231A1/de not_active Application Discontinuation
  • 1986-05-28 EP EP19860903178 patent/EP0223796A1/de not_active Withdrawn
  • 1986-05-30 ES ES556104A patent/ES8800383A1/es not_active Expired
  • 1986-05-30 PT PT8268886A patent/PT82688A/pt not_active Application Discontinuation

Non-Patent Citations (1)

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