PURPOSE: To set various recording optical output intensity for compensating a relative speed change and to compensate an aging characteristic change of a semiconductor laser in a laser drive controller for current-driving the laser to obtain an optical output having a predetermined intensity.

CONSTITUTION: A driving current corresponding optical intensity data to be supplied from an interpolation controller 8 is output to drive a semiconductor laser 13. On the other hand, a photodiode 14 detects an optical output intensity emitted from the laser 13, level-compares the intensity with a plurality of predetermined threshold values, and forms a comparison result signal thereby to interpolate in the controller 8, thereby deciding an arbitrary optical output intensity.