| 摘要 |
PROBLEM TO BE SOLVED: To remove the influence of ripple noise from a value detected by a toner concentration sensor.SOLUTION: An image forming apparatus includes: an image forming unit 5 for forming a toner image; an image carrier 6 which carries the toner image; and a toner concentration sensor 15 which detects toner concentration of the toner image formed on the image carrier 6 at a predetermined sampling period. The image forming apparatus also includes: a ripple noise period calculation unit 113 which calculates a ripple noise period generated from one or more AC component generation sources 8, 9 located near the toner concentration sensor 15, from AC component frequency information of the AC component generation sources 8, 9; a sampling period control unit 114 which varies the sampling period according to the calculated ripple noise period; and an averaging process unit 100 which averages a plurality of sampling values output from the toner concentration sensor 15, according to the varied sampling period. |
