Multi-layer optical disc, information recording method and information reproducing method

Abstract

According to one embodiment, single-sided dual-layer recordable disc 100 may be used. Information recording is performed by forming mark and space portions on data area DA using modulated laser power. Pp denotes the maximum laser power or peak power for forming the mark portion, and Pb denotes the bias power for forming the space portion. Power ratio Pb/Pp is calculated for each of recording layers L0 and L1. Information is recorded on any of the recording layers L0 and L1 based on the result of calculation. Here, the calculated power ratio Pb/Pp changes among the recording layers L0 and L1, thereby optimizing the recording condition for a multi-layer recordable optical disc within relatively short time.

1 . An optical disc comprising:
 a recording layer, the recording layer being configured to store information by using a peak power and a particular power arranged next to or subsequent to the peak power, a power level of the particular power being lower than that of the peak power, wherein   the optical disc includes a parameter information area including
 parameter information relating to a ratio of a numerator corresponding to the particular power to a denominator corresponding to the peak power, and 
 read power information relating to a power for reading the information stored in the disc. 
   
     
     
         2 . A method of recording information on an optical disc comprising a recording layer, the recording layer being configured to store information by using a peak power and a particular power arranged next to or subsequent to the peak power, a power level of the particular power being lower than that of the peak power, wherein
 the optical disc includes a parameter information area including
 parameter information relating to a ratio of a numerator corresponding to the particular power to a denominator corresponding to the peak power, and 
 read power information relating to a power for reading the information stored in the disc, 
 the method comprising: 
   recording information on the disc.   
     
     
         3 . A method of reproducing information from an optical disc comprising a recording layer, the recording layer being configured to store information by using a peak power and a particular power arranged next to or subsequent to the peak power, a power level of the particular power being lower than that of the peak power, wherein
 the optical disc includes a parameter information area including
 parameter information relating to a ratio of a numerator corresponding to the particular power to a denominator corresponding to the peak power, and 
 read power information relating to a power for reading the information stored in the disc, 
   the method comprising:   reading recorded information from the disc.