PURPOSE: To provide a laser recorder for recording an image on a substrate in response to a video signal having frequency defining a pixel time (a time imaging an independent pixel).

CONSTITUTION: A power stable smart laser part 20 is equipped with a semiconductor laser 22, a power controller 26 and, desirably, a photodetector 24 feeding back a feedback signal to a power controller 26. The laser 22 and the photodetector 24 can be formed on a semiconductor substrate. The power controller 26 outputs an intensity control current to the laser 22 on the basis of the high frequency variable duty cycle bit stream received from a D/A converter 30 and the feedback signal provided from the photodetector 24. Differently from a conventional apparatus wherein the peak power applied to the laser changes, the laser is operated or stopped in relation to the change of a duty cycle.