| 摘要 |
<p>PROBLEM TO BE SOLVED: To form line width of a vertical line and a horizontal line substantially the same in an image forming apparatus such as a digital copier using an LED array capable of executing a gradation expression as an exposure unit. SOLUTION: A controller 60 compares image data for one line of an image reader 50 in a main scanning direction with a prescribed threshold value, judges the case in which signals each having the prescribed threshold value or more are continued for prescribed number or more as the horizontal line and the case in which the signals each having the prescribed threshold value or more are the prescribed number or less (e.g. 1 pulse) and thereafter signals each having a threshold value or less are continued for prescribed number or more as the vertical line. The controller 60 corrects a control signal so that the light emitting time of the LED of the exposure unit 33 corresponding to the part judged as the vertical line becomes shorter than that of the LED of the unit 33 corresponding to the part judged as the horizontal line when the part judged as the vertical line is included in image data for the one line of the reader 50 in the main scanning direction.</p> |
