Printing apparatus

摘要

A printing apparatus includes an image reader (16) for reading an image on a printed paper sheet to obtain image data, and a controller (18) for controlling the image reader to obtain image data about a color chart including solid patches once for every predetermined number of printed sheets or at every predetermined time interval which is inputted and set. The controller processes the image data to compute a printed density of each solid patch. Measurement data including the printed density are sequentially stored in a storage section (30) in association with the number of printed sheets or time. The measurement data stored in the storage section may be displayed by a display section (31) or outputted to a print section (32) in the form of history data indicating measurement data transitions. Thus, the printing apparatus including a device for measuring printed sheets can perform history management on the measurement data for every predetermined number of printed sheets or at every predetermined time interval. <IMAGE>