memory 16 as the above individual characteristic information in an example of the characteristic information shown in fig4 b the inclination rate is stored for each recording power level the level u201c a u201d in fig4 a of the recording light waveform accordingly the microcomputer 22 determines an optimum write strategy by utilizing the inclination rate for each recording power level stored in the memory 16 thereby to execute stable recording actually though an optimum recording power for the disc is different in accordance with recording sensitivity of the disc which is an object of information recording the stable recording characteristic can be obtained during recording information to the discs having different sensitivity if the inclination rate for each recording power level of the recording light waveform is stored like the above moreover in the case of the disc whose necessary recording power is largely different in accordance with the change of recording speed such as cd r dvd r dvd r and the like it is effective that an optimum write strategy can be determined according to the recording power like this next the bias level will be described as an example of the characteristic which may be different between different pickups in the case of the recording light waveform of the multi pulse type shown in fig3 a.