| 摘要 |
<P>PROBLEM TO BE SOLVED: To cancel the problem of nonlinearity of a conventional hologram recording and playback system and to attain both of high recording density by reduction of a signal light size by an aperture and enhancement of a data transfer rate by a low oversampling rate (OSR). <P>SOLUTION: When data reading is performed by irradiating a hologram recording medium with reference light upon playback, coherent light having the same phase as a playback image obtained according to irradiation with the reference light and intensity higher than the absolute value of the minimum value of the amplitude of the playback image is radiated together with the reference light. A square root of a reading signal obtained by an image sensor is calculated and a DC component in accordance with the coherent light is removed to perform data playback. Linear reading is made possible by such a reading operation and a constraint condition for the OSR and an aperture size can be the condition (OSR>the aperture size) by a sampling theorem. <P>COPYRIGHT: (C)2010,JPO&INPIT |
