Patent ID: 8144379
Filing Date: 2012-03-27
Classification: G03H,G11B

Abstract:
1. A recording and reproducing device comprising: a light source for irradiating a hologram recording medium including a recording layer in which data is recorded by interference fringes between signal light and reference light and a reflection type circular polarization film formed under said recording layer and formed so as to output circularly polarized light in a same rotation direction as incident circularly polarized light as reflected light with said signal light and said reference light; an intensity modulating section configured to subject light output from said light source to spatial light intensity modulation in pixel units, a signal light area as a region for generating said signal light and a reference light area as a region for generating said reference light being set in the intensity modulating section; a polarization beam splitter for receiving incident light via said intensity modulating section as forward path light and receiving incident reproduced light obtained as reflected light from said hologram recording medium as backward path light; a selective polarization direction controlling section configured to perform selective polarization direction control for changing a polarization direction of light in at least one of a reference light beam region as a light beam region of light via said reference light area and a signal light beam region as a light beam region of light via said signal light area by 90° or not changing the polarization direction according to a driving signal at a position receiving said forward path light incident via said polarization beam splitter; a linearly polarized light/circularly polarized light converting section configured to convert linearly polarized light obtained through said selective polarization direction control by said selective polarization direction controlling section into circularly polarized light, and convert circularly polarized light obtained as reflected light from said hologram recording medium into linearly polarized light; and a driving controlling section configured to control said selective polarization direction controlling section so as to obtain a state of polarization directions of light in said reference light beam region and light in said signal light beam region being an identical direction at a time of recording and obtain a state of polarization directions of light in said reference light beam region and light in said signal light beam region being orthogonal to each other at a time of reproduction, as driving controlling section configured to control said selective polarization direction controlling section by supplying said driving signal.