  We propose and demonstrate a new imaging technique to noninvasively see
through scattering layers with the aid of a spatial light modulator (SLM). A
relay system projects the incoherent light pattern emitting from the scattering
layer onto the SLM. Two coded phase masks are displayed, one after another, on
the SLM to modulate the projected scattered field. Two corresponding intensity
patterns are recorded by a digital camera, and subtracted one from the other in
the computer to obtain a bipolar matrix. A modified phase retrieval algorithm
is used to retrieve the object information from this bipolar matrix.
