[1][2] Salisbury screens operate on the same principle as optical antireflection coatings used on the surface of camera lenses and glasses to prevent them from reflecting light.
The easiest to understand Salisbury screen design consists of three layers: a ground plane which is the metallic surface that needs to be concealed, a lossless dielectric of a precise thickness (a quarter of the wavelength of the radar wave to be absorbed), and a thin glossy screen.
The thickness of the dielectric is made equal to a quarter of the wavelength (λ/4) of the expected radar wave.
Adding this much bulk to the surfaces of aircraft can unacceptably degrade aerodynamic performance.
Research is being conducted on ultra thin Salisbury screens using the Sievenpiper HIGP (high impedance ground plane) (source: Wiley Periodicals, Inc., Microwave Opt.