US Patent 9219314 Artificial electromagnetic material

An artificial electromagnetic material includes at least one material sheet. Each material sheet includes a substrate and a plurality of artificial microstructures attached to the substrate. Each substrate is virtually divided into multiple of substrate units arranged into an array. A pair of artificial microstructures is attached to each substrate. The pair of artificial microstructures includes a first artificial microstructure and a second artificial microstructure with different shapes. The dielectric constant of artificial electromagnetic materials gradually increases from zero in a certain frequency range, therefore the material has a low dielectric constant in the certain frequency range and can meet some needs of special situation.