| 摘要 |
PROBLEM TO BE SOLVED: To provide a simple and small sized information recording/reproducing device which is manufactured at a low cost and is capable of stably performing recording/reproducing to each recording layer in the depth direction. SOLUTION: A first light beam 10 is condensed by an objective lens 17 on an optional guide track layer within an information recording medium 1 which is provided with plural recording areas having a recording layer respectively in a multi-layer shape in the depth direction and also which is provided with plural guide track layers respectively corresponding to these plural recording layers, a second light beam 20 is condensed on a desired recording layer within a recording area corresponding to a guide track layer, on which the first light beam 10 is condensed, by the objective lens 17 via a collimator lens 22 movable in the direction of the optical axis, and whereby information is recorded or reproduced. |
