Proposal for Rewritable Microholographic Recording Using Polarization-Sensitive Materials

Rewritable microholographic recording using polarization-sensitive materials has been proposed. Two types of optical configuration (i.e., single-channel detection and differential detection) have been presented. Recording operation is carried out by focusing two light beams with orthogonal polarization states in the recording medium. The polarization states of the two light beams are switched with switchable waveplates according to recording signal. The polarization directions of light in which the two light beams are synthesized are recorded in the recording medium as a polarization diffraction grating. Readout operation is carried out by focusing a light beam with a certain polarization state in the recording medium. A reflected light beam from the polarization diffraction grating is detected by a photodetector. The readout signal is obtained from the intensity or the polarization state of the reflected light beam. This technology features not only rewritability but also overwritability. Readout signal simulation considering polarization has demonstrated the validity of this technology. (C) 2012 The Japan Society of Applied Physics