| 摘要 |
PURPOSE:To improve the track position detecting accuracy of a magnetic recording and reproducing device such an electronic still camera by adjusting a position of a photodetector corresponding to a reference track position on a magnetic disc, with two-step constitution of rough adjustment by a linear motion and a fine adjustment by a rotational motion. CONSTITUTION:A photodetector 6 is installed to the side face of a head carriage 3 so that it moves in the linear direction along the direction of a feed screw 2 together with the head carriage 3. On the other hand, a light shielding body 9 is placed on the same shaft as the feed screw 2 so as to be rotated synchronously with the feed screw 2. Accordingly, when the photodetector 6 executes linear movement, also a light shielding part 92 of the light shielding body 9 rotates, and it advances into a groove 61 of the photodetector 6 and cuts off light, an output of the detector 6 drops suddenly. In this way, a reference track position can be detected with high accuracy. |
