| 摘要 |
PURPOSE:To perform tracking with high precision regardless of the movement precision of a carriage by performing tracking operation independently of the carriage. CONSTITUTION:A linear motion holding mechanism 22 is not in operation during seeking operation, so a facing yoke 23 is not attracted by a flat plate type electromagnet 21. The carriage 10, therefore, moves freely. The holding mechanism 22 operates after the seeking operation and the electromagnet 21 attracts the facing yoke 23 to hold the carriage 10. An oscillatory motion holding mechanism 20 stops its operation at this point of time. An optical pickup unit 15 is therefore allowed to oscillates through a bearing 16. Namely,the follow-up control to a track is carried out. The correction width of eccentricity from the track is about 300mum, so the angle of rotation around the bearing part is extremely small, and the influence of variation in a rotational direction is hardly exerted. |
