Information recording method, information reading method, and optical disc device

摘要

An optical disc device and information recording/reading method for an optical disc in which a recording layer is formed through volume recording by aligning recording tracks, which hold information, in a homogenous recording region that does not internally have a layer defining a recording position. The information recording method includes a step in which a first recording layer forming a complex recording layer is formed by forming a recording track while recording information by focusing a main beam at a predetermined depth position in the recording region, and a step in which a second recording layer forming the complex recording layer is formed by forming a recording track while recording information by focusing the main beam at a depth position that is separated from the first recording layer in a depth direction by a depth offset greater than ⅙ of a wavelength of the main beam.

主权项

1. An information recording method for forming a recording layer in an optical disc, through volume recording by aligning recording tracks, which hold information in a homogenous recording region that does not internally have a layer defining a recording position, the information recording method comprising:
forming a first recording layer forming a complex recording layer, by forming a recording track while recording information, by focusing a main beam at a predetermined depth position in the recording region; and forming a second recording layer forming the complex recording layer, by forming a recording track while recording information, by focusing the main beam at a depth position separated from the first recording layer in a depth direction by a depth offset greater than one-sixth (⅙) of a wavelength of the main beam; wherein a focal position of the main beam is controlled by using a first focus error signal; wherein the first focus error signal is detected from a guide beam reflected from a reference layer the guide beam being focused on the reference layer, and the guide beam having a wavelength that differs from the wavelength of the main beam; and wherein an effective track pitch of the complex recording layer is one-half (½) of a track pitch of the first or second recording layer.