A method for determining a read power of a laser beam includes a step of setting a power of a laser beam to a recommended recording power Pw' and forming a recording mark train including at least one of a recording mark having a length shorter than a resolution limit and a blank region having a length shorter than the resolution limit in an optical recording disc, thereby recording test data therein. The method also includes a step of setting the power of the laser beam to a recommended read power Pr' and reproducing the test data recorded in the optical recording disc, a step of judging whether or not signal characteristics of a reproduced signal obtained by reproducing the test data satisfies reference conditions, and determining an optimum read power of the laser beam based on the result of the judgment.

 
Web www.patentalert.com

< Material for welding and welded article

> Optical information recording medium, and recording and reproducing apparatus of the same

~ 00470