Patent ID: 7133349
Filing Date: 2006-11-07
Classification: G11B

Abstract:
1. A recording apparatus for an optical disc that has a sector including a plurality of frames, said recording apparatus comprising: a first generating unit operable to generate a channel signal according to main information to be recorded in a frame in the sector, the channel signal being composed of High sections and Low sections, the High sections and Low sections each corresponding to run lengths of a first channel bit value in the main information, and each transition point between a High section and a Low section corresponding to a second channel bit in the main information; a modulation unit operable to phase-modulate the channel signal generated by said first generating unit to obtain a superposition channel signal on which a bit value of sub information is superposed, the superposition channel signal being a channel signal in which phase-leading transition points and phase-lagging transition points are arranged in accordance with a predetermined rule; and a writing unit operable to write recording marks into the frame in the sector so as to achieve recording of the main information on which the sub information is superposed, wherein positions of edges of the recording marks are determined in accordance with the transition points in the superposition channel signal, and wherein: the phase-leading transition points and the phase-lagging transition points cause jitters; and an edge displacement amount Δt is determined from σ′≧√{square root over (σ