| 摘要 |
PHN 11.896 15 23-09-1987 "Electro-optical scanning device." The invention relates to an electro-optical device, comprising a frame (1), a movable holder (5) in which an objective (7) having an optical axis (9) is secured, bearing means (25, 27, 29, 31) for supporting the holder so that it can be translated and rotated, a magnet (13) which is secured to the frame and cylindrical wall portions (1B) which wall portions with the magnet form an annular air gap (17) with a radial magnetic field, a focussing coil (19) which is secured to the holder and which is movable in the air gap, and a plurality of tracking coils (33) which are secured to the holder and which are situated on the outer side of the focussing coil. The tracking coils extend through recesses (37) between the cylindrical wall portions of the frame, the turns of the tracking coils being situated in or substantially in radial planes containing the axis of rotation (11) of the holder and the turns of each of the tracking coils together forming a continuous free space (35). Bridge members (39) of a soft-magnetic material extend through the free spaces and are magnetically linked and mechanically connected to the cylindrical wall portions on both sides of the tracking coils. (Figure 1.) |
