Patent ID: 7050367
Filing Date: 2006-05-23
Classification: G11B

Abstract:
1. An optical information recording method which irradiates a laser light spot having a predetermined diameter to an optical information recording medium according to a digital signal consisting of a first level indicating a pit forming period and a second level indicating a pit non-forming period to form a pit having a length corresponding to the pit forming period on the optical information recording medium, the method comprising the steps of: changing sequentially a recording power of laser light to be irradiated to the optical information recording medium to record on the optical information recording medium before actual recording of information and also detecting asymmetry for every recording power to determine a first relation between the asymmetry and the recording power; fixing the recording power to a predetermined recording power and sequentially changing a spatial positional relation of the laser light to the optical information recording medium to record on the optical information recording medium and also detecting a reflected light amount ratio related to the asymmetry and pits having different lengths for every spatial positional relation to determine a second relation between the asymmetry and the reflected light amount ratio; determining a third relation between the recording power and the reflected light amount ratio according to the first relation and the second relation and also determining an optimum reflected light amount ratio corresponding to an optimum recording power; and detecting the reflected light amount ratio at the time of actual recording of information to determine a recording power corresponding to the detected reflected light amount ratio according to the third relation, and correcting the recording power so that a difference between the detected reflected light amount ratio and the optimum reflected light amount ratio becomes zero.