IMAGE FORMING DEVICE

摘要

PURPOSE:To obtain the image forming device with a forgery preventing means for banknote and securities by devising the device such that the forgery prevention means cannot be removed or revamped to prevent forgery of the banknote and securities. CONSTITUTION:A forgery prevention circuit 14 and an A/D converter 11 essential to an image forming system are formed on a processing unit being one chip. Furthermore, the processing unit 10 has an identification code generating circuit 15 and a coding circuit 13 and outputs coding data. A processing unit 20 uses a decoding circuit 21 and a discrimination circuit 22 to decode the coded data and applies recognition processing to the data and to discriminates whether or not the processing unit 10 is a revamped unit. When the processing unit 20 discriminates the revamped unit, an OR circuit 27 and a noise generating circuit 23 in the processing unit 20 invalidates normal picture processing.