The synchronous control in the main scanning direction is performed in the synch circuit based on the BD synch signal.
Using the BD signal generated based on the light from laser A, the DC controller PCB generates the BD synch signal for laser A and the BD synch signal for laser B.
The image data written to line memory is read out by the readout enable signal (RE_A, RE_B) generated based on the BD synch signal (BD_A, BD_B) for output