Patent ID: 7835248
Filing Date: 2010-11-16
Classification: G11B

Abstract:
1. An optical disk apparatus comprising: an optical pickup which irradiates an optical disk with a laser beam; and a recording power setting circuit which sets a recording power of the laser beam, wherein the recording power setting circuit performs test write with a predetermined test power to a first track on the optical disk, performs test write with the same test power as the test write in the first track to a second track adjacent to the first track, reproduces the first track and the second track to obtain reproduction signals respectively, and determines whether or not the test power is set to a recording laser power in recording main information based on a relationship between the obtained reproduction signals, and wherein the recording power setting circuit reproduces the first track and the second track to obtain parameter values concerning a quality of the reproduction signal respectively, and determines whether or not the test power is set to a recording laser power in recording main information based on magnitude of a change between a first parameter value obtained from the first track and a second parameter value obtained from the second track, and wherein the recording power setting circuit determines whether or not the test power is set to a recording laser power in recording main information based on a condition that the magnitude of the change between the first parameter value and the second parameter value exists within a range of a predetermined first threshold and, at the same time, based on a condition that the first parameter value exists within a range of a predetermined second threshold, and wherein the recording power setting circuit obtains a plurality of samples of the first parameter value and the second parameter value by repeating the test write and the reproduction while changing the test power, selects the samples in which the magnitude of the change between the first parameter value and the second parameter value exists within a range of a predetermined first threshold and, at the same time, the first parameter value exists within a range of a predetermined second threshold, and sets a test power corresponding to one of the selected samples to a recording laser power in recording main information.