Coherent optical signal transferring on request by use of a BaTiO3 crystal

We demonstrate experimentally a setup with which a two-dimensional picture can he transmitted from one plane to another at a signal request of the tat ter plane and the original picture continues to propagate unhindered along its original direction to the next stage. The setup makes use of photorefra ctive four-wave mixing and the self-pumped phase conjugation for its operat ion. Some means for increasing the contrast of the final transmitted image have been discussed. (C) 2000 Optical Society of America OCIS codes: 190.53 30, 070.5040, 190.5040, 190.7070, 200.4650.