Patent ID: 7154833

Claim:
A laser power selecting method for selecting a laser power to record modulated codes on an information recording medium by use of a laser beam, comprising the steps of: recording a predetermined signal pattern on the information recording medium; reproducing the predetermined signal pattern recorded, and calculating an asymmetry value from the predetermined signal pattern reproduced; obtaining a change rate of the asymmetry value relative to a laser power; and selecting a laser power at which the change rate assumes a maximum value, wherein the predetermined signal pattern is a combination pattern which combines sequentially a first signal having at least one mark and at least one space which are respectively longer in length than the shortest mark and shortest space among modulated codes to be recorded, and a second signal having a plurality of marks equal in length to the shortest mark among the modulated codes to be recorded and a plurality of spaces shorter in length than the shortest space among the modulated codes to be recorded.