| 摘要 |
PURPOSE:To easily improve the resolution of position detection at a low cost by mounting a light reflector formed with the arrangement of a light reflecting pit group on the movable portion side of an actuator and reading the light reflecting pits by a reflection type light pickup. CONSTITUTION:In a direct drive motor 1 as an actuator, when an AC current flows through a stator coil 5, a driven body connected to a flange 13 is driven for rotation by a relative motion between a fixed stator 3 and a rotor 8. A position detector generates a signal corresponding to a relative-positional relationship between the stator 3 and the rotor 8. The light reflecting disc 20 of the detector is formed with linear pits according to a prescribed rule in the surface of a transparent substrate. A light pickup 30 irradiates the disc 20 detecting light focused on it by an automatic focus controller. Reflected light obtained by the reflection of detecting light from the pits is detected and a light detection signal is generated in accordance with a detected result to generate a position detection signal. |
