US Patent 7593302 Recording strategy in multilevel recording

An optical information recording method includes the steps of irradiating laser light onto cells provided on a track of an optical information recording medium, recording on the optical information recording medium multilevel information including information of a level zero for which no information pit is formed, by changing, for each of the cells, widths in a track direction or sizes of information pits in the cells, and, for recording the information of a level zero, irradiating the laser light at a power that is greater than an erasing power for erasing the information pits and that does not permit formation of the information pits.