Patent ID: 8729511

Claim:
An electromagnetic wave beam splitter, comprising a functional layer made of at least one metamaterial sheet, and impedance matching layers arranged respectively on an electromagnetic wave incident surface and an electromagnetic wave emergent surface of the functional layer, wherein the metamaterial sheet comprises a sheet-like substrate and a plurality of artificial microstructures attached on the substrate, the artificial microstructure being in an axially symmetric structure; each of the metamaterial sheets has the same refractive index distribution; the metamaterial sheet comprises a circular region and an annular region concentric to the circular region; a refractive index increases continuously as a radius increases and refractive indices at the same radius are the same within the circular region; a refractive index decreases continuously as a radius increases and refractive indices at the same radius are the same within the annular region; the artificial microstructures have the same geometric shape; sizes of the artificial microstructures increase continuously as the radius increases and sizes of the artificial microstructures at the same radius are the same within the circular region; and sizes of the artificial microstructures decrease continuously as the radius increases and the sizes of the artificial microstructures are the same at the same radius within the annular region.