Patent ID: 7564751

Claim:
A laser power adjustment method of performing laser power strength adjustment by performing test writing into a test writing area of a recording medium, comprising steps of: obtaining an integrated value Sn for each kind of laser power Pwn set at the time of the test writing from a modulation factor m(Pwn) of a reflection light intensity obtained at the laser power Pwn using an expression “Sn=m(Pwn)×Pwn 2 ”; approximating linearly relational characteristics of the integrated value Sn and the laser power Pwn for at least two integrated values Sn and the laser powers Pwn; obtaining laser power Pwth at which the approximated integrated value Sn becomes zero from the linearly approximated relational characteristics; and obtaining optimum laser power Pw based on the laser power Pwth, wherein the optimum laser power Pw is obtained from a target γ value of the recording medium using an expression “Pw=Pwth×{1+1/(γ+1)}”)}”, the target γ value is read from the recording medium.