linear velocities along the optical disk to sample at least first and second bottom levels of the laser power and operates in the write mode for monitoring a linear velocity at a point of the optical disk where the signal is to be recorded and for calculating a target bottom level at the monitored linear velocity by interpolation of the sampled first and second bottom levels thereby outputting the bottom level control signal according to a difference between the calculated target bottom level and the actual bottom level of the laser power application_number US 96535701 A description next preferred embodiments of the present invention will be described with reference to the accompanying drawings fig1 is a block diagram showing the configuration of a laser output control for an optical disk recording reproducing apparatus according to an embodiment of the invention in fig1 a laser light from a laser diode ld 2 driven by a laser driving device 1 is irradiated to an optical disk for reading information written in the optical disk and for writing information in the optical disk the target value of the output power of the laser light in this case is equal to the read level rp of fig4 in the reading mode and equal to the bottom level bp or the write level wp of fig4 in the write.