Light transmitting electromagnetic wave shielding composite materials using electromagnetic wave polarizing effect

Light transmitting and electromagnetic wave shielding material using a cross-polarizing effect of unidirectionally aligned electrically conductive fiber-dielectric composite has been developed. Two-electrically isolated unidirectionally aligned continuous electrically conductive fiber layers were incorporated into an optically transparent polymethylmethacrylate (PMMA) matrix. Electromagnetic wave shielding by the polarizing effect of the composite was examined by the free-space method in a frequency range from 18 to 24 GHz. The composite shields electromagnetic wave with a small expense of light transmittance of the PMMA matrix. Effect of fiber spacing, angle of fiber axis direction, and polarizing mode of incident electromagnetic wave are discussed based on experimental results. It is concluded that the use of the polarizing effect is an effective way to obtain an optically transparent electromagnetic shielding material. (c) 2007 American Institute of Physics.