Extraction of quasi-straightforward-propagating photons from diffused light transmitting through a scattering medium by polarization modulation.

The utilization of light polarization is proposed to extract quasi-straightforward-propagating photons from diffused light transmitting through a scattering medium under continuously operating conditions. Removal of a floor level normally appearing on the dynamic range over which the extraction capability is maintained is demonstrated. By use of pulse-based observations this cw scheme of extraction of quasi-straightforwardpropagating photons is directly shown to be equivalent to the use of a temporal gate in the pulse-based operation.