| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical scanner configured to improve rotation convergence time of a rotary polygon mirror as compared with a case where a scanning start signal is not synchronized with a phase detection signal.SOLUTION: In an optical scanner 50, a phase detection element 102 exists in a division position (polarization point) of a magnetic pole of a driving magnet 94B in synchronization with the time when a synchronous detector 88 receives a light beam L reflected by a rotary polygon mirror 70. In the optical scanner 50, an edge of a reflection surface 71 of the rotary polygon mirror 70 is aligned with a phase of the driving magnet 94B. The driving magnet 94B is arranged so that the edge of the reflection surface 71 is located near the central part of an S-pole of the driving magnet 94B. |
