Electromagnetic shielding window of two dimensional area is between the isolation of metal, to control the electric field, magnetic field and the electromagnetic wave by a area to another area induction and radiation. Specific tell, is to use shields will yuan parts, circuit, assemblies, cable or the entire system of interference source surrounded, prevent interference to spread outside the electromagnetic field; Use a shielded will receive circuit, equipment or system surrounded and to prevent their get the outside the influence of the electromagnetic field.