Patent ID: 7668060

Claim:
An optical disc apparatus that records or reproduces information by irradiating laser light onto an optical disc having a plurality of recording layers, through an object lens, the optical disc apparatus comprising: a write signal generator to generate a write signal for recording on the optical disc; a laser diode to generate laser light; a laser drive circuit to drive the laser diode in accordance with the write signal; and a controller to: confirm that an unrecorded recording layer absent information recorded thereon is included in the plurality of recording layers of an optical disc mounted inside the apparatus; cause a test recording operation in a test recording area of the recording layer to be conducted with an initial focus offset value; calculate, from results of the test recording operation, a recording power level for focus offset adjustment; control the write signal generator to generate a signal for focus offset adjustment; cause the signal for focus offset adjustment to be test-recorded in a required area of the unrecorded recording layer at the recording power level; read the signal for focus offset adjustment and evaluate quality thereof; calculate and set a focus offset value of the recording layer, based on results of the evaluation; cause another test recording operation to be conducted with the set focus offset value by changing the recording power level; calculate an appropriate recording power level for actually recording information; control the write signal generator to generate a signal for recording information; and cause the recording information to be actually recorded at the recording power level.