Copier having a security function

摘要

A digital copier or a complex copier having a facsimile function is provided with a security function for keeping a record of persons who copied or transmitted images, the dates of copying or transmission and the kinds of the images in a manner which is not known to a third person. When a scanner included in the copier is used, a document image is electrically or magnetically recorded in a security unit removably mounted on the copier. The document image is thinned or otherwise reduced in scale before written to the security unit. A keyword, password or similar information identifying a person is input on the copier. The document image is recorded in the security unit together with the person's identification and the date and time when the scanner is used. A plurality of such document images stored in the security unit are printed on a single paper at the same time.