Patent ID: 7760595
Filing Date: 2010-07-20
Classification: G11B

Abstract:
1. An optical disc device comprising: a spindle motor for rotating a disc; a motor driving circuit for applying a voltage to the spindle motor to drive the spindle motor; an optical pickup for irradiating the disc with an optical beam; and a detector for, after the motor driving circuit starts voltage application to the spindle motor, sequentially measuring pit lengths based on reflection light, on the disc, of the optical beam irradiated by the optical pickup for respective predetermined periods of time, acquiring largest pit lengths in the respective measurements, and based on a difference between the largest pit lengths corresponding to the adjacent measurements in measurement sequence, detecting that the spindle motor is in short condition, wherein, upon detection by the detector that the spindle motor is in short condition, the motor driving circuit stops the voltage application to the spindle motor.