Patent ID: 7990828
Filing Date: 2011-08-02
Classification: G11B

Abstract:
1. A method of controlling focus on a label side of a light-scribe disc, comprising: (1) dividing a label side of the light-scribe disc into a predetermined number of sections; (2) performing focus process for each section to detect and record a side beam added signal (SBAD); (3) comparing the SBADs of each section to derive a maximum SBAD; (4) utilizing a focus volt and a spoke corresponding to the maximum SBAD derived from each section to approximate a preliminary focus volt level curve; (5) compensating a predetermined volt for the preliminary focus volt level curve to form a compensated focus volt level curve, and performing focus process of the label side to detect and record SBADs; (6) comparing the SBAD derived from the preliminary focus volt level curve and the SBAD derived from the compensated focus volt level curve in each section; and (7) utilizing the focus volt and the spoke corresponding to the maximum SBAD derived in step (6) to approximate a calibrated focus volt level curve.