Patent ID: 7751289

Claim:
An optical disc apparatus which irradiates a rotating optical disc with laser beams from an optical pickup, the apparatus comprising: a disc motor which drives the rotation of the optical disc; a movement and guide mechanism unit which moves the optical pickup approximately in the radial direction of the optical disc by means of a rotary driving force of the slide motor; a motor drive circuit which drives the disc motor and the slide motor; a motor control unit which forms a signal for controlling the motor drive circuit; a laser diode which emits the laser beams; a laser drive circuit which drives the laser diode; a recording signal generator which generates a recording signal to be supplied to the laser drive circuit; a recording failure detector which detects a failure of information recording condition by means of the read signal based on reflected laser beams from the optical disc; a β measurement unit which measures a β value of a recording mark recorded on the optical disc by means of the read signal based on reflected laser beams from the optical disc; a recording power correction and calculation unit which compares the measurement β value with a target β value, and calculates a correction factor or correction amount of recording power and optimal recording power according to the difference between the two β values; a recording power setup unit which sets the optimal recording power calculated; and a control circuit which controls the motor control unit, the recording signal generator, the β measurement unit, the recording failure detector, and the recording power correction and calculation unit; wherein the control circuit, if the recording failure detector detects a failure of information recording condition during operation of information recording, directs the laser drive circuit or the recording signal generator to stop recording operation, directs the motor control unit to change the number of rotations of the optical disc to a low-speed value based on the signal from the motor control unit, directs the optical disc apparatus to seek a selected recording region and perform OPC processing and trial write operation with the number of rotations for low-speed operation, directs the β measurement unit to measure a resultant β value of the trial write operation, directs the recording power correction and calculation unit to calculate optimal recording power based on the β value; and directs the optical disc apparatus to start the operation of information recording with the number of rotations for low-speed operation.