Patent ID: 9114652
Filing Date: 2015-08-25
Classification: B29C,B33Y,B41J

Abstract:
1. A printer comprising: a printhead configured with a plurality of inkjets to eject material; a supply of thermal substrate configured to move thermal substrate to a position opposite the printhead to receive material ejected from the printhead; an optical sensor configured to generate electrical signals corresponding to an optical density of a location on the thermal substrate; an actuator operatively connected to the optical sensor to move the optical sensor to a position opposite the thermal substrate onto which material has been ejected; a heater configured to expose a length of thermal substrate to heat; and a controller operatively connected to both actuators, the optical sensor, the heater, and the printhead, the controller being configured to operate the printhead to eject a predetermined number of material drops from each inkjet onto the thermal substrate to enable the predetermined number of material drops to form a test dot for each inkjet on the thermal substrate, to operate the heater to darken the length of thermal substrate exposed to heat, to operate the actuator to move the optical sensor to a position opposite the thermal substrate to generate image data of the substrate and the test dots on the substrate, and to identify inoperative inkjets in the printhead with reference to the data received from the optical sensor that corresponds to optical densities of the thermal substrate at a plurality of locations on the thermal substrate.