Patch measurement device and printing apparatus incorporating the same

摘要

There is provided a patch measurement device which, even if the position of a patch in a control strip printed on a printed material is incorrectly detected, does not affect the controlling of the printing apparatus. A data storage section 271 in a patch measurement device 27 stores printed-image data Dpd. A reference mark detection section 272 detects a reference mark rm in the printed-image data Dpd, and generates position data thereof. A reference mark position data comparison section 273 compares the position data against past position data stored in a reference mark position data storage section 274 to determine the validity of the position data. If the position data is valid, a patch position detection section 275 detects a patch whose color density is to be measured. A color density measurement section 276 generates color density measurement data of the printed patch. A color density calculation section 277 calculates color density information Dct by using current and past color density measurement data stored in a color density measurement data storage section 278.