Patent ID: 7379084

Claim:
An image forming apparatus that controls a plurality of laser beams based on image data of different colors and performs exposure scanning operation for a photoconductor drum to form an image, comprising: first and second laser source sections that irradiate a polygon mirror with laser beams from different directions; first and second light scanning sections that allow the polygon mirror to reflect the laser beams from the first and second laser source sections toward different optical axis directions to scan the laser beams at a predetermined deflection angle; a first beam detector that is disposed at the beam incident end in the scanning direction of the first light scanning section and receives the first laser beam to detect the start of the scanning; a second beam detector that is disposed at the beam incident end in the scanning direction of the second light scanning section and receives the second laser beam to detect the start of the scanning at an earlier timing than the first beam detector does; and a laser controller that utilizes the detection result of the first beam detector to set sampling start timing in common between the first and second image data, writes first and second image data in a memory based on the detection results of the first and second beam detectors, and controls the first and second laser source sections based on the image data read out from the memory.