Patent ID: 8064309
Filing Date: 2011-11-22
Classification: G11B

Abstract:
1. A recording/playback apparatus comprising: optical head means for applying laser light to an optical recording medium to read and write information represented by marks and spaces from and into the optical recording medium; laser drive pulse generating means for generating laser drive pulses in accordance with information to be recorded and supplying the generated laser drive pulses to the optical head means to allow the optical head means to apply the laser light for recording the information; power setting means for setting power of the laser light; evaluation value calculating means for calculating a quality evaluation value, which serves as an index to the quality of a signal recorded based on a setting condition to which the laser drive pulses are set, from a signal read from the optical recording medium by the optical head means; and adjustment control means for performing an adjustment setting for the laser drive pulses generated by the laser drive pulse generating means, wherein the adjustment control means performs control such that recording operations for adjusting the laser drive pulses are performed on the optical recording medium by performing a first recording operation of writing test data at a first level of power of the laser light and at different adjustment setting conditions, and performing a second recording operation of writing the test data at a second level of power of the laser light different from the first level of power and at the different adjustment setting conditions to obtain quality evaluation values for the different adjustment setting conditions under the first and second levels of power of the laser light, calculates an initial front mark edge position error being a difference between a detected front mark edge position and a detected reference front mark edge position of a predetermined reference pattern, and an initial rear mark edge position error being a difference between a detected rear mark edge position and a detected reference rear mark edge position of the predetermined reference pattern corresponding to a condition that a front edge position shift amount and a rear edge position shift amount are zero, determines the adjustment setting for the laser drive pulses based on the quality evaluation values obtained by the evaluation value calculating means and the calculated initial front mark edge position error and the calculated rear mark edge position error, when the test data recorded during the recording operations is read for the different adjustment setting conditions under the first and second levels of the power of the laser light, and sets the determined adjustment setting in the laser drive pulse generating means, wherein the different adjustment setting conditions include settings for front edge position shift amounts by which front edge positions are shifted and rear edge position shift amounts by which rear edge positions are shifted, and wherein the predetermined reference pattern includes a predetermined combination of a space and a mark.