| 摘要 |
PURPOSE:To easily manufacture the small quantity of an optical disk recording the same information by modulating the pulse width of a laser to be satisfied with a specified equation at the time of recording an EMF signal while rotating an information recording medium at a linear velocity faster than at the time of reproducing. CONSTITUTION:When the EMF signal is recorded by being irradiated with a laser beam while rotating the recording medium providing a recording layer on a substrate with a pre-groove with the linear velocity faster than at the time of reproducing, the pulse width TLD (n) of the laser beam is modulated so as to be satisfied with the equations I-IV. That is, the modulation is performed so that the equations I-III at the time of nT-pit length and the equations II-IV at the time of 3T-pit length are satisfied. Where, n=4-11, T = clock cycle at recording, T1 = clock cycle at reproducing, V1=constant linear velocity at reproducing, V = constant linear velocity at recording, a=0.5-1.5, TLD (3) = laser pulse width to record a pit with 3T pit-length, f=0.03-0.6, mT = light emitting time shortened from last of light emitting time of laser with nT-pit length. |
