Optical recording and reproducing apparatus

An optical recording and reproducing apparatus for recording information on an optical recording medium having plural recording layers arranged in a laminating direction and reproducing the information from the optical recording medium, comprising:

• laser power setting means for using an optimum power set value Pwpn obtained from a result of performing a test recording on a recording layer n as an initial power value in the test recording on another recording layer m to set an optimum power Pwpm for the other recording layer m,
• wherein the laser power setting means includes;
• means for approximating a relation Rn between a recording power and a characteristic parameter of the recording layer n from the result of performing the test recording and on the recording layer n;
• means for obtaining the optimum power set value Pwpn for the recording layer n from the relation Rn and a target value of the characteristic parameter;
• means for setting the optimum power set value Pwpn for the recording layer n as the initial power value in the test recording on the other recording layer m;
• means for approximating a relation Rm between a recording power and a characteristic parameter of the recording layer m based on the characteristic parameter obtained from the result of performing the test recording on the other recording layer m and the relation Rn between the recording power for the recording layer n and the characteristic parameter;
• and
• means for obtaining the optimum power set value Pwpm for the recording layer m from the relation Rm and a target value of the characteristic parameter;
• means for obtaining plural β value from the result of performing the test recording on the recording layer n;
• means for obtaining an approximation line Ln for approximating a relation between the recording power and the β value from the plural β values;
• means for obtaining the optimum power set value Pwpn for the recording layer n from the approximation line Ln and a target β value;
• means for obtaining an inclination In of the approximation line Ln;
• means for setting the optimum power set value Pwpn as the initial power value in the test recording on the other recording layer m;
• means for obtaining a sole β value from the result of test recording on the other recording layer m;
• means for obtaining an approximation line Lm for approximating a relation between the recording power and the β value from the β value obtained from the result of test recording on the other recording layer m and the inclination In;
• and
• means for obtaining the optimum power set value Pwpm for the other recording layer m from the approximation line Lm and the target β value.