| 摘要 |
<p>The presence of invisible ink drops may be relatively easily detected on a print medium (30) by detecting the changes in specular reflection between the print medium and the print medium upon which invisible ink drops are located. An optical sensor (200) having a detector (240) for capturing diffuse reflections and a detector (242) for capturing specular reflections may be implemented to detect the presence of both sufficiently colored ink drops as well as invisible ink drops. In one respect, the location of the detected invisible inks may be utilized to determine whether an ink ejection element (102) that fired the drops of invisible inks is offset or misaligned. In another respect, the drop size of the ink drops may be detected to determine the health of the nozzles (107). In this regard, the method of detecting the presence of invisible ink drops may be implemented as a routine or sub-routine to determine ink ejection element alignment, apply a positional calibration of the ink ejection element, and apply a printing mask. <IMAGE></p> |
