| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus that makes a document written in thin characters adequately legible and reduces the amount of toner consumption. <P>SOLUTION: The black rate BR of image data to be printed is calculated. Duty that becomes smaller in percentage as the black rate BR becomes higher is set in a duty register 47. In addition, a thinning pattern type is set in a pattern type register 41 in accordance with the black rate BR. The thinning pattern stored in the pattern type register 41 is read from a thinning pattern memory 44. An AND circuit 46 calculates the logical AND of: the outputs of the thinning pattern and an Edge signal from the OR circuit 45; and image data VData to be printed. The output of the result is supplied to a level modulation circuit 48 as black pixel data to be printed. The black pixel data are transmitted to a laser diode 49 on a duty stored in the duty register 47. <P>COPYRIGHT: (C)2004,JPO&NCIPI |
