The regenerative light intensity control unit in the optical memory, regenerative light intensity control manner and optical recording media

摘要

PROBLEM TO BE SOLVED: To prevent a recording mark on a recording layer from being destructed even when a regenerative signal amount from a regenerative light quantity control pattern is detected erroneously and to improve reliability in a regenerative light quantity controller by setting an upper limit value of a regenerative light quantity so as not to arrive at a temp. erasing the mark. ;SOLUTION: A regenerative light quantity limit means 8 detects irradiation light (a) from a semiconductor laser 2 by a photodiode 3b to control it. A regenerative light quantity range data read means 7 reads the beforehand recorded regenerative light quantity range data from a regenerative light quantity range data recording area provided on a read-in area of an optical disk, and sets a limit value in the regenerative light quantity limit means 8 so that the light quantity of the irradiation light (a) isn't enlarged excessively based on these data. A CPU 10 measures the number of error (e) and an amplitude ratio (r) while changing the light quantity of the irradiation light (a), and sets the control target value of the regenerative light quantity in the limit means 8 based on the amplitude ratio (r) when the number of errors (e) become minimum.;COPYRIGHT: (C)1999,JPO