Patent ID: 9575314
Date: 2017-02-21
CPC Classifications: B41J,G02B

Claim:
1. An image forming apparatus comprising: a photosensitive member; a scanning device including a light source configured to emit a laser beam and a polygon mirror formed with a plurality of reflection surfaces, the scanning device configured to scan the photosensitive member with the laser beam by reflecting the laser beam by the reflection surfaces of the rotating polygon mirror; a generating device configured to generate a pulse signal required to modulate the laser beam based on image data, and to output the pulse signal to the scanning device; and a storage unit configured to store information associated with a deviation amount between a length of a scanning line formed by each reflection surface of the plurality of reflection surfaces and a reference value, wherein the generating device is further configured to generate the pulse signal by inserting or deleting one or more pulses each having a width smaller than a width corresponding to one pixel of the image data into or from a pulse signal corresponding to the image data based on the information stored in the storage unit, so as to adjust lengths of scanning lines formed by the plurality of reflection surfaces to be closer to the reference value, wherein the generating device is further configured to divide one scanning line into a plurality of segments, and to insert or delete one or more pulses each having the width smaller than the width corresponding to one pixel of the image data into or from each segment, and wherein a number of the segments of the scanning line is determined based on a number of pulses to be inserted into or to be deleted from the scanning line.