| 摘要 |
<P>PROBLEM TO BE SOLVED: To record/reproduce information in a multiplex manner by using the 3-dimensional element of a signal light. <P>SOLUTION: A signal light Ob whose advancing path is changed by a mirror M1 becomes a converged light by a lens L1, and made incident on a lens L2 after it is subjected to space modulation by a space modulator SLM1. When the lens L2 is moved in an optical axis direction, the focus of the signal light varies whenever the lens is moved, and these signal lights of different focuses are sequentially recorded by interference at a reference light Re1 and a hologram recording medium H1. By setting data displayed in the space modulator SLM 1 for each varying of the focus of a signal light, i.e., a data sequence, different, information is recorded in a multiplexed manner by using the 3-dimensional element of the signal light, i.e., the element of an optical axis direction. When the reference light Re1 is applied to the hologram recording medium H1, a plurality of converged lights of difference focuses are generated. These converged lights are separated to be received by moving the lens L2 or a pinhole in the optical axis direction, converted into signals, and thus the original information is reproduced. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
