| 摘要 |
PROBLEM TO BE SOLVED: To provide an image formation device that can form a toner layer thickness in control of an amount of toner adhesion equal to or more than solid density.SOLUTION: A control unit 50 is configured to apply a DC bias recorded in a look-up table 51 via a high voltage power source unit 40 to a developing roll 12 to form a half tone patch P on an intermediate transfer belt 14. A toner adhesion-amount sensor 19 is configured to detect an amount of reflection light from the half tone patch to measure an amount of toner adhesion of the half tone patch P. The control unit 50 is configured to estimate a sensor output of the toner adhesion-amount sensor 19 with respect to the amount of toner adhesion equal to or more than solid density, and derive the DC bias for forming a toner layer thickness of the amount of toner adhesion equal to or more than the solid density on the basis of the DC bias, the sensor output measuring the half tone patch P and the sensor output to be estimated with respect to the amount of toner adhesion equal to or more than the solid density.SELECTED DRAWING: Figure 2 |
