31results about How to "Improve electromagnetic shielding efficiency" patented technology

The invention discloses a weaving process for anti-electromagnetic-radiation air layer weft knitted fabric. The front and back surfaces of the knitted fabric are weaved through a weaving machine by using cotton or cotton-polyester blended fabric as raw materials. Tissue of the fabric is produced by a double-sided dobby air layer structure. The stainless steel filaments are weaved in a doubling manner into the knitted fabric. The stainless steel filaments are formed on the front surface of the fabric in a manner of locally forming a ring. Float length between adjacent stainless steel filamentsis in the air layer structure. The invention has the advantages of high electromagnetic shielding efficiency, strong performance of anti-electromagnetic-radiation, soft feel, wrinkle-free property and launderability.

The invention discloses a heat-generating electromagnetic shielding plastic-based composite material, which is composed of the following raw materials in parts by mass: 40-70 parts of plastic matrix, 10-45 parts of ferrous metaferrite, 10-30 parts of Composite carbon black, 5-10 parts of compatibilizer, 0.5-1 part of lubricant, 0.5-1 part of antioxidant, described compatibilizer is POE-g-MAH, ABS-g-MAH A sort of. The composite material prepared by the invention has good mechanical properties and electromagnetic shielding properties, and the inner surface temperature is 60°C within 3-5 seconds under 60V voltage, the calorific value is controllable, the heating is faster, the electromagnetic shielding efficiency is high, the cost is low, and it is easy to form It can be processed and recycled, and can also meet the requirements of environmental protection, and realize the country's strategic deployment of building a resource-saving and environment-friendly society.

The invention discloses an infrared transparent window with an electromagnetic shielding function. The infrared transparent window is prepared from a sapphire substrate and an ITO (indium oxide) basedsemiconductor film lamination located above the sapphire substrate with a metal organic chemical vapor deposition method, wherein a deviation angle of 0-2 degrees is formed between the surface of thesapphire substrate and the c crystal face of sapphire, and the sapphire substrate is subjected to double-sided polishing, and the thickness of the sapphire substrate is 100-10000 mu m; the ITO basedsemiconductor film lamination is prepared from an unintentionally doped ITO buffer layer and an Sn-doped ITO electromagnetic shielding main body layer by laminating; the thickness of the unintentionally doped ITO buffer layer is 10-1000 nm, and electron mean concentration is not higher than 1*10<19>cm<-3>; the thickness of the electromagnetic shielding main body layer is 0.2-200 mu m, and electronmean concentration is not higher than 5*10<19>cm<-3>. Square resistance of the infrared transparent window is lower than 100 omega / sq, the transmittance of the infrared transparent window in a wavelength range of 0.78-2.5 mu m is higher than 70%, the transmittance of the infrared transparent window in a wavelength range of 2.5-5 mu m is higher than 50%, electron mobility is higher than 70 cm<2> / Vs, and electromagnetic shielding efficiency in a frequency range of 1-18 GHz is higher than 12 dB.

A bidirectional wave absorption strong electromagnetic shielding optical window of a multilayer graphene mesh / metal mesh laminated structure belongs to the optical transparent member electromagnetic shielding technology field. The electromagnetic shielding optical window utilizes the different light transmission and microwave shielding characteristics performed by the graphene mesh films when the graphene mesh films have different mesh unit hole area ratios to organically combine the low-reflection and partial absorption microwave characteristics of the graphene mesh films with the strong electromagnetic reflection characteristics of the high-light transmission dual-layer metal meshes, and the multilayer graphene mesh films are placed at the two sides of the dual-layer metal meshes to form a multilayer structure. The dual-layer metal meshes separated by the graphene mesh films are used as the transparent reflection layers, and the graphene mesh films separated by the transparent mediums are used as the transparent absorption layers. By the structure, the radio frequency radiation at the two sides of the optical window can penetrate the absorption layers simultaneously and repeatedly to be absorbed strongly, so that the bidirectional strong shielding and low-reflection characteristics are realized, the visible light has a high light transmission rate by transmitting the laminated structure once. The electromagnetic shielding optical window solves the problem that a conventional transparent electromagnetic shielding method can not consider the bidirectional low-electromagnetic reflection, the strong electromagnetic shielding and the high light transmission simultaneously.

The invention relates electromagnetic screen complex film made by electric polyaniline and carbon nano pipe and preparing method. The method comprises the following steps: dispersing the carbon nano pipe into chloroform tobacco extract mixed with 4-dodecylbenzene sulfonic acid, then mixing it with polyaniline m-cresol solution doped with camphor sulfonic acid to form filming solution, pouring the filming solution on the slide glass, getting the complex film of polyaniline and carbon nano pipe whose concentration is 5wt%-50wt% in form filming solution. The optimum electric conductivity of complex film is 212 S / cm and mechanics intensity is 14.53Mpa. When the frequency of complex film is between 106Hz and 109Hz and thickness of complex film is 20mum, the electromagnetic screen efficiency is between 35dB and 40dB. The more the electric conductivity and thickness of complex film, the higher the electromagnetic screen efficiency.