Patent ID: 6937264

Claim:
A laser scanning control apparatus comprising: a light source driven in accordance with image data defined in pixels and adapted to emit a laser beam; a rotating polygon mirror for scanning the laser beam emitted from the light source in a main scanning direction of an image bearing member; and a correction portion for, every one or more correction points on a main scanning line of the image bearing member to be scanned with the laser beam, extending the pixel length for each pixel located in the correction point concerned to thereby correct the scanning magnification of the main scanning line, and for changing the rotational speed of the rotating polygon mirror to correct the magnification in a sub scanning direction to thereby correct the output magnifications, wherein the correction portion has ring-like shift registers, the ring-like shift registers are synchronized with a high-frequency clock signal, a logical product of a pulse having the same width as the period of the high-frequency clock signal and bit data divided among the shift registers from the image data is used as an output pulse adapted to drive a laser, and when the pixel length is extended, the number of ring-like shift registers through which the pulse passes circularly is increased.