| 摘要 |
PURPOSE:To detect micro unevenness of recording density quality, particularly density distribution and to cope with the uneveness, in an electrophotographic image forming device. CONSTITUTION:A test toner image pattern of 20mm by 10mm is formed on a margin part of a sensitizing body 9, toner image reflection density of each part is sampled at 24 points in total both in the main and the auxiliary scanning directions so as to detect standard deviation of the density distribution, that is, dispersion, and when it is more than a reference value Th, abnormality in recording density is informed. |
