| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming apparatus configured to efficiently correct image density with high accuracy.SOLUTION: A digital multifunction device 11 allocates development bias voltages into four levels, to form first patch images (S11), measures CTD values of the first patch images 63a (S12), measures CTD values and forms second patch images (S13), the second patch images being formed by use of one development bias voltage selected from among a plurality of development bias voltages and used in forming the first patch images, measures CTD values of the second patch images 73a, again (S14), calculates an average of the measured CTD values (S15), calculates a difference between the average CTD value and the first level-3 CTD value (S16), calculates a final target CTD value by adding the difference to the first temporary target CTD value (S17), and calculates a final ΔV corresponding to the final target CTD value (S18).SELECTED DRAWING: Figure 5 |
