CARTRIDGE, IMAGE FORMING APPARATUS AND IMAGE FORMING SYSTEM

摘要

PROBLEM TO BE SOLVED: To prevent developer and a recording medium from being wasted by successively accurately detecting developer amount, showing appropriate cartridge exchanging time and preventing an image defect from occurring. SOLUTION: A plane antenna 6 for measuring the range of 120 g to 40 g developer and a plate antenna 15 for measuring <=50 g developer are provided in a developer storing container 4. When a detected value by the antenna 6 shows >=80 g, the minimum detected voltage value by the antenna 15 is measured and the obtained value is stored in a storage means 20 as PAF(plate antenna full). When the antenna 15 measures <=40 g developer, the detected voltage value is corrected according to the PAF so as to obtain the developer amount.