An apparatus and method are disclosed for laser raster scanning a substrate in an XY plane wherein a single motor is used to provide synchronized X-Y scanning by two mirrors positioned orthogonally and which move linearly in an XY plane relative to each other by the rotation of the motor shaft. A preferred embodiment uses a specially designed cam to provide back and forth laser scanning motion and an intermittent gear to provide indexing of the laser. The apparatus and method may be configured for various scan speeds, spot sizes, Y-axis indexing and X-axis scan at the object plane. Over scanning of the active XY area of the object plane is preferred to provide constant velocity and energy density over the active XY area.