Controlling the propagation of light in disordered scattering media
  This thesis describes experimental work on the use of wavefront shaping to steer light through strongly scattering materials. We find that scattering does not irreversibly scramble the incident wave. By shaping the incident wavefront, we make opaque objects focus light as sharply as aberration free lenses. We use feedback from a target behind, or in, an opaque object to shape the incident wave. This way, light is focused through, or inside, opaque objects for the first time ever. 
I. M. Vellekoop