| 主权项 |
1. An apparatus comprising:
a lens (36, 236) to focus light reflected from liquid droplets ejected from a plurality of columns (26, 226, 227) of nozzles (30) along an object plane (44, 244) tilted with respect to a print media travel direction; a sensor (38, 238) having a detection plane (48, 248) tilted with respect to the media travel direction to be impinged by the light from the liquid droplets; and a controller (40, 240, 440) to receive signals from the sensor (38, 238) based on impingement of the detection plane (48, 248) by the light so as to detect a vertical trajectory of the nozzles (30) based on the signals. |
