US Patent 8716677 Wavefront correction of light beam

An apparatus includes a transverse scanning optical system in the path of a first light beam traveling along a first optic axis; a wavefront correction system in the path of a second light beam traveling along a second optic axis, the wavefront correction system including a wavefront correction device having a spatial phase profile on its surface; a beam combiner that receives the first light beam and the second light beam and outputs an interference beam having a beat frequency equal to a difference frequency between the first light beam and second light beam; and a detection system placed relative to a random scattering medium, which is in the path of the interference beam. The detection system detects measurement light produced by the random scattering medium while the interference beam strikes the random scattering medium.