Patent ID: 9079440
Filing Date: 2015-07-14
Classification: B41J

Abstract:
1. A printer for forming objects comprising: a substrate having a surface and an edge along a perimeter of the substrate; a printhead configured to eject material onto the surface of the substrate; a light source positioned to direct light into the edge of the substrate; an optical sensor positioned to receive light emitted by the ejected matter on the surface of the substrate, the optical sensor being configured to generate image data corresponding to the surface of the substrate and the ejected matter on the surface of the substrate; and a controller operatively connected to the printhead, the light source and the optical sensor, the controller being configured to operate the printhead to eject material onto the surface of the substrate according to a predetermined pattern, to activate the light source selectively, to receive image data generated by the optical sensor while the light source is directing light into the edge of the substrate, and to detect inoperative inkjets in the printhead with reference to the received image data and the predetermined pattern.