| 摘要 |
PURPOSE:To improve the freedom of designing by using exclusively coils of motor structures for tracking and focusing, inside and outside yokes and magnets respectively. CONSTITUTION:A coil 44 for focusing is wound around the outer circumference of a bobbin 43 provided to a lens holding arm 37. The focus control is performed by shifting the arm 37 in the thrust direction together with an inside yoke 33, a ring magnet 34 and an outside yoke 35. While the arm 37 contains a coil 45 for tracking on the outer surface of a support bar 38 and is rotated around a support shaft 29 together with an outside yoke 25 a magnet 26, and an inside yoke 36. In such constitution, the independent designing is possible for both tracking and focusing motors. This constitution improves the designing freedom of an optical information reader. |
