Abstract:
An apparatus detects inoperative inkjets during printing. The apparatus includes a light transmitting substrate onto which a test pattern of material is ejected. A light source directs light into the substrate and an optical sensor generates image data of a surface of the substrate. Light propagates through the substrate unless it reaches a position where the material is present on the surface. Thus, the material emits light so a contrast exists between the surface of the substrate and the material emitting light. By comparing the image data to the positions of the light emitting areas on the surface, inoperative inkjets are detected.
Abstract:
An inkjet printer estimates ink usage in the printer with reference to image pixels and a history of inkjet firing for each inkjet. The printer includes an apparatus that generates an ink mass for each image pixel with reference to the image pixel and a predetermined number of previously ejected image pixels and identifies a total ink mass measurement for a printhead with reference to the ink masses generated for the image pixels of an image to be printed by the inkjet printer.
Abstract:
A method of printer operation identifies inkjets to operate in each scanline to eject sneeze drops or, in an alternative approach, identifies the cross-process direction scanlines within a page to be printed by the printer where each inkjet ejects sneeze drops. The methods use a binary grayscale code counter that generates a sequence of binary grayscale code numbers and every other output of the sequence is bit reversed to spread the sneeze drops over the pages of the printer output so the sneeze drops are not perceptible to a human observer.
Abstract:
A method and system compensates for malfunctioning inkjets using contone values for an image prior to the contone values being rendered for printing of the image. The method generates contone values for color space components in a compensation level for each malfunctioning inkjet. The contone values in each compensation level are modified with reference to a profile selected for each malfunctioning inkjet and with reference to the modification of the contone values in the vicinity of each malfunctioning with the compensative level. The modified contone values of each compensation level are merged with the contone values in the vicinity of each malfunctioning inkjet. The contone values are then rendered and used to operate inkjets for forming an ink image on an ink receiving member.
Abstract:
A printer detects malfunctioning ejectors during printing of three-dimensional objects or two-dimensional printed matter. The printer operates the printhead or printheads in the printer to form convex drops of material on a substrate. A camera is positioned to minimize light reflections from the substrate into the camera. The camera is configured to generate image data of the light reflected from the substrate and specularly from the convex drops on the substrate. A controller analyzes the image data to identify malfunctioning inkjets.
Abstract:
An apparatus detects inoperative ejectors during printing of three-dimensional objects. The apparatus operates the printhead or printheads in the printer to form test pattern on a substrate. A pneumatic sensor directs a pneumatic stream towards substrate and measures the pneumatic impedance. The impedance differences between area where the test pattern is formed and bare areas are analyzed to identify inoperative inkjets.
Abstract:
An inkjet printer estimates ink usage in the printer with reference to image pixels and a history of inkjet firing for each inkjet. The printer includes an apparatus that generates an ink mass for each image pixel with reference to the image pixel and a predetermined number of previously ejected image pixels and identifies a total ink mass measurement for a printhead with reference to the ink masses generated for the image pixels of an image to be printed by the inkjet printer.