| 摘要 |
PROBLEM TO BE SOLVED: To execute the stable tracking control and to reproduce signals in parallel from plural tracks by using multiple light beams in an information recording/reproducing device, and simultaneously to enable also the information recording operation by arranging a single light beam. SOLUTION: Variable diffraction grating elements 1103, 1113 capable of bringing out or removing the diffracted light beam by the impressed voltage are introduced, and at the time of recording, the single light beam is arranged to secure the intensity, and the stable tracking or the parallel reproduction is executed by arranging the plural light beams at the time of reproduction. By the information recording/reproducing device using this light beam branching means, the stable control is executed or the signals from the plural tracks are reproduced in parallel by the use of multiple light beams, which was difficult in the conventional practice, and simultaneously the information recording is also attained by arranging the single light beam. |
