| 摘要 |
<P>PROBLEM TO BE SOLVED: To assure an excellent light receiving state and to perform reasonable signal reproduction irrespective of the slippage of light reproduced from a hologram medium. <P>SOLUTION: Though signal light of a hologram recording part 20 is supplied in a state being in agreement with an optical axis of an optical system irrespective of a shape (board thickness, angle, refractive index or the like) of the hologram medium 61, the reproduced light at the time of reproduction at a hologram reproduction section 30 is taken out in a state being shifted from the optical axis of the optical system according to the shape (board thickness, angle, refractive index or the like) of the hologram medium 61 and depending on a degree of the slippage, reasonable sensing in a latter photodetector 32 may be hindered. Therefor reasonable sensing state is maintained by providing an optical axis slippage compensation section 50 and moving a light receiving system (a light receiving optical system 31 and the photodetector 32) corresponding to amount of slippage of the optical axis. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
