Patent ID: 7944794
Filing Date: 2011-05-17
Classification: G11B

Abstract:
1. An optical disc apparatus that records recording marks in a plurality of mark layers by irradiating predetermined light onto a recording medium on a basis of information to be recorded, comprising: first focus position adjusting means for adjusting a focus of a first light beam onto a first mark layer of the recording medium, in a direction of an optical axis of the first light beam; second focus position adjusting means for adjusting a focus of a second light beam onto a second mark layer of the recording medium, in a direction of an optical axis of the second light beam; an objective lens disposed so that the first light beam and the second light beam pass through the objective lens to the recording medium; objective lens control means for irradiating a third light beam onto a positioning layer of the recording medium through the objective lens and for controlling a position of the objective lens on a basis of the third light beam reflected from the positioning layer so that the third light beam is focused onto the positioning layer; focus control means for controlling the first focus position adjusting means and the second focus position adjusting means independently such that the first light beam and the second light beam are focused onto the first mark layer and the second mark layer of the recording medium, respectively; and recording control means for forming the recording marks in the first mark layer and the second mark layer of the recording medium by irradiating the first light beam and the second light beam, respectively, according to the information to be recorded.