Q:How to screen magnetic field
A: Normally, we use the iron sheet to screen the magnetic field. A magnetic shielding need high permeability material, the Iron Nickel Alloy which has the very high magnetic permeability is the material can meet such standard. When the magnetic field we need to shield is very strong; if only use single shield material, it either can not meet shielding demand, or will be saturated. On this occasion, one solution is to increase the thickness of the material; and the more effective solution is to use the combination shielding assembly, which is to leave airspace between one shielding and the other shielding. That is to say, Filling with any permeability material (such as aluminum) in the airspace for supporting when put one shielding into another. The effect of using combination shielding assembly is much higher than single shielding, and the combination shielding assembly can decrease the magnetic field to very low degree.