Patent ID: 8395790

Claim:
An image forming apparatus comprising: a photosensitive member; a light source configured to emit a laser beam based on input image data; a deflecting unit configured to deflect the laser beam emitted from the light source so that the photosensitive member is scanned with the laser beam; a detecting unit configured to detect the laser beam deflected by the deflecting unit and to output a detection signal according to the detection of the laser beam; a storage unit configured to store the detection signal in synchronization with a first clock signal and to output a bit pattern of a plurality of bits corresponding to the stored detection signal in synchronization with a second clock signal having a frequency higher than a frequency of the detection signal and lower than a frequency of the first clock signal; an outputting unit configured to output a timing signal based on the bit pattern output from the storage unit and to output a phase signal corresponding to a change position of the bit data in the bit pattern; and a control unit configured to control, based on the timing signal and the phase signal output from the outputting unit, timing to emit the laser beam from the light source based on the input image data.