Patent ID: 7796334

Claim:
An apparatus for reflecting electromagnetic radiation, comprising: a plate having two planar transverse faces, having a thickness between the two faces, being composed of an optically isotropic, electrically non-conductive material, and having a plate index of refraction; a plurality of the plates; the faces for all of the plates lying in parallel; the plates being spaced apart from each other by a plurality of gaps, respectively; the gaps having a uniform width; the gaps being filled with a medium having a medium index of refraction; incident radiation having a wavelength within the medium; and the thickness, the plate index of refraction, the width of the gaps, the medium index of refraction, and the wavelength having the following quantitative relationships: t p n p 2 =n m λ m /2 and w g n m =λ m where: t p =the thickness the plate; n p =the plate index of refraction; n n =the medium index of refraction; λ m =the wavelength of the incident radiation within the medium; and w g =the width of the gaps.