| 摘要 |
PURPOSE:To obtain the head of a mobile magnet system which can narrow the gap between a coil and a magnet and has a low power consumption and a high driving sensitivity, by forming the surface of the magnet, which faces the position adjusting coil of an objective lens, into a convex. CONSTITUTION:Tracking coils 24a and 24b are stuck to coil fixing plates 3a and 3b, and focusing coils 25a and 25b are stuck on them, and magnets 16a and 16b are attached to a mobile body 10 so that they face said position adjusting coils. Surfaces of magnets are formed into convexes. Consequently, right and left ends of magnets 16a and 16b do not collide with coils 25a and 25b and gaps between them are narrowed when the mobile body 10 is turned for position adjustment. Thus, a magnetic field space is used effectively to obtain the optical head of the mobile magnet system which has a low power consumption and a high driving sensitivity.
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