PROGRESSIVEDIFFERENTIALPUSH-PULLMETHOD FORDUAL LAYERBLU-RAYDISCRECORDING

Progressive Differential Push-Pull (DPP)method wasdeveloped. In caseofduallayer Blu-ray disc recording, conventional DPPsignal is disturbed bythestray lights reflectedfrom other recording layer and tracking servo sometimes becomes unstable. This paper presents an example ofoptical headfor duallayer Blu-ray Discrecording. Photo detector oftheoptical headtosuppress theinfluence ofstray lights wasdeveloped.