DEVELOPING DEVICE, IMAGE FORMING APPARATUS, AND TONER DENSITY DETECTION METHOD

摘要

PROBLEM TO BE SOLVED: To provide a developing device that can suppress radiation noise emitted from the device while maintaining the detection accuracy of the density of toner.SOLUTION: A developing device includes a toner density sensor having an LC oscillation circuit in every developing unit. Capacitors 1283-M and 1284-M of the LC oscillation circuit which constitute the toner density sensor 128-M for magenta, have a capacitance determined for magenta. The toner density sensors detecting the density of toner in developer of other different colors have similarly their capacitances different from each other for each color.