| 摘要 |
PURPOSE:To always hold vertically an optical axis of an objective lens and an optical disk surface, and to decrease a data read error by supporting a supporting shaft so that it always leans to a prescribed radial direction of a bearing by magnetic force. CONSTITUTION:At least the peripheral part of a supporting shaft 4 of an objective lens holding body 1 is constituted of a non-magnetic material, a bearing 2 is provided on an objective lens holding body 1 and has magnetic force whose prescribed radial direction is a main direction, and as for the supporting shaft 4, at least a part which is fitted to this bearing 2 consisting of a magnetic material. Accordingly, by the magnetic force of the bearing 2, the supporting shaft 4 is attracted in the main direction of its magnetic force, a clearance in the direction corresponding to the main direction of the magnetic force between this supporting shaft 4 and the bearing 2 is eliminated, and the supporting shaft 4 is always leaned and supported in the prescribed radial direction of the bearing 2 by the magnetic force. In such a way, an optical axis of an objective lens can be held so as to be always vertical against an optical disk surface, and also, the device can be formed by a small-sized and simple structure.
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