Production method of foaming electromagnetic wave lens

The invention provides a production method of an electromagnetic wave lens with better comprehensive performance and lower cost in a high-frequency band range. The preparation method comprises the following steps: S1, mixing at least two liquid materials to carry out a chemical reaction of polyurethane foaming with an independent closed-cell structure, wherein high-dielectric-constant particles are also added into one of the liquid materials; s2, chemical reaction is carried out in a mold, and the mixed liquid material is foamed and cured into a polyurethane foaming piece; s3, another polyurethane foaming piece is directly manufactured according to the steps S1 to S2 on the basis of the previous polyurethane foaming piece with the assistance of other molds; and S4, repeating the step S3 to prepare the electromagnetic wave lens with a multi-layer wrapping structure, wherein the dielectric constant value of the prepared electromagnetic wave lens is lower and lower from the innermost layer to the outermost layer