Patent ID: 7645014
Filing Date: 2010-01-12
Classification: C09D

Abstract:
1. A method, comprising: ejecting at least one drop of ink onto a medium from at least one of at least two ink pens containing different colors of the ink and an infrared light absorbent dye, wherein each of the different colors of the ink is mixed with the same infrared light absorbent dye and wherein one of the different colors of the ink is cyan-colored ink that is mixed with the infrared light absorbent dye; illuminating, with an infrared light source, a location on the medium at which the at least one drop from the at least one of the at least two ink pens is intended to impact and a location on the medium at which the at least one drop from the at least one of the at least two ink pens has actually impacted with an infrared light source; and measuring absorbance of the infrared light with a sensor of infrared light intensity.