Imaging through a scattering wall using absorption

Abstract

An object hidden behind a cloudy wall is shown to become visible when the wall is made absorbing. The underlying principle is that the absorption in a random medium preferentially reduces the intensity of the multiple scattered light (noise) over the ballistic signal (image). The intensity of the noise can be reduced below the ballistic signal intensity when the medium is made sufficiently absorbing, thus allowing us to see through an otherwise opaque random scattering wall.