| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus decreasing the number of correcting frequency of image signal. <P>SOLUTION: The image forming apparatus has a main position controlling means which changes density of intervals of beam spot positions on a scanning line, by one line unit or a unit not smaller than the one line unit, to perform correction of magnification, a sub-position controlling means which changes the density of the intervals of the beam spot positions on the scanning line by one pixel unit to correct the magnification, a sub-correction time calculating means which calculates a difference between a reference time which can be set by operating only the main position controlling means and the time measured by a time difference measuring means, and a judging means for judging a size between the amount of the corrected time calculated by the sub-correction calculating means and the amount of a regulating time set in advance. As a result of the judgement by the judging means, until the amount of the corrected time exceeds the amount of the regulating time, the correction of magnification is performed by the sub-position controlling means without operating the main position controlling means. As a result of the judgement by the judging means, at the time when the amount of the corrected time exceeds the amount of the regulating time, the main position controlling means is operated to perform the correction of magnification. <P>COPYRIGHT: (C)2007,JPO&INPIT |
