Patent ID: 8690285
Filing Date: 2014-04-08
Classification: B41J,H04N

Abstract:
1. A printing apparatus, comprising: a transport unit that transports a medium in a first direction; a head that dispenses ink while moving in a second direction orthogonal to the first direction; and an optical sensor that emits light on the medium while moving in the second direction and outputs a signal based on intensity of reflected light, the printing apparatus being configured to, when correcting a dispensing amount of the ink by using a patch pattern composed of a patch of a first gradation level, a patch of a second gradation level denser than the first gradation level, and a plurality of patches each presenting a different gradation level between the first gradation level and the second gradation level: form the patch pattern such that the patches are located at different positions in the second direction; output the signal of the patch of the second gradation level and the signal of a patch in the patch pattern other than the patch of the second gradation level, thereby measuring density; output the signal of a position in a blank region on the medium onto which the ink has not been dispensed, the position being located at the same position in the second direction as the patch of the second gradation level, and the signal of a position in the blank region located at the same position in the second direction as the patch other than the patch of the second gradation level, thereby measuring medium density; output the signal on the assumption that the patch of the second gradation level is formed at the position of the patch other than the patch of the second gradation level, on the basis of the signals outputted in the measuring of the density and in the measuring of the medium density, thereby predicting density; and correct the dispensing amount corresponding to the gradation level of the patch other than the patch of the second gradation level, on the basis of the signal outputted in the predicting of density.