| 摘要 |
<P>PROBLEM TO BE SOLVED: To set an optimum power ratio with high precision in a short time concerning a binary pulse recording system by considering nonlinearity in a laser emission characteristic. <P>SOLUTION: A signal is recorded with a recording laser, having binary power levels (Po, Pm, provided that Po>Pm) relative to an optical disk, concerning a recording power setting method. A power ratio k(=Po/Pm) is defined as a prescribed value, a test signal, which is obtained by changing recording power Po stepwise, is recorded in the optical disk, and then, the test signal recorded in the optical disk is reproduced. A β value, which indicates asymmetry of amplitude, is acquired from the reproduced signal, so as to calculate the change rate Δβ(=dβ/dPo) of the β value relative to the recording power Po. The value of the calculated change ratio Δβ in a target β value is compared with a target Δβ value. Based on the result, the power ratio k of the recording laser is corrected and set. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
