Patent application number | Description | Published |
20080303854 | SYSTEMS AND METHODS FOR DETECTING INTERMITTENT, WEAK AND MISSING JETS WITH AN INLINE LINEAR ARRAY SENSOR - Systems and methods are provided for detecting intermittent, weak or missing jets of a printer. The detection is implemented using a test pattern. Detected failed jets may be confirmed using a verification target. A printhead containing nozzles corresponding to detected failed jets may be wiped or purged. | 12-11-2008 |
20090033691 | System and method for adjusting ink jet uniformity based on drop mass history - A method for processing input document data uses a drop mass history for ink jets in a print head to adjust other document data processing. The method includes ejecting ink in a plurality of patterns onto an image substrate from a plurality of ink jets, each drop in a pattern corresponding to one drop mass history in a plurality of drop mass histories, identifying a relationship between drop masses for the drops in an ejected pattern and a reflectance parameter for the ejected pattern, measuring a reflectance value for each pattern ejected onto the image substrate, and identifying a drop mass value for each drop mass history in the plurality of drop mass histories, each drop mass value being identified from the measured reflectance value for each pattern and the identified relationships between the drop masses and the reflectance parameter for each pattern. | 02-05-2009 |
20090040261 | System and method for calibrating a printing system to compensate for sensor artifact using non-complementary illuminations of test patterns on an image substrate - A system removes a light sensor artifact from a light sensor in a printer that is used to obtain reflectance measurements from test patterns printed on an image substrate. The system includes a print head for ejecting a plurality of pixels having a first single color in a test pattern onto an image substrate, a light source for illuminating the test pattern on the image substrate with a light, a light sensor for measuring reflectance of the first portion of the test pattern with reference to a light having a color that is non-complementary to the first single color of the test pattern, measuring reflectance of the first portion of the test pattern with reference to a light that is complementary to the first single color of the test pattern, and measuring reflectance of the second portion of the test pattern with reference to the complementary light, the second portion including an area that overlaps the first portion of the test pattern, and a sensor controller configured to scale the reflectance of the first portion measured with reference to the non-complementary light to minimize a difference between the reflectance of the first portion measured with reference to the complementary light and the reflectance of the second portion measured with reference to the complementary light in the overlapped area. | 02-12-2009 |
20090047032 | SYSTEM FOR MEASURING MARKING MATERIAL ON A SURFACE, SUCH AS IN COLOR XEROGRAPHY - A printing apparatus has a substantially shiny photoreceptor imaging surface, and a photosensor array disposed to receive specularly-reflected light from the imaging surface. A quantity of toner is placed on the imaging surface, and data is derived based on light reflected from the imaging surface. The reflected light is filtered to a color effectively complementary to the toner color. The system avoids noise caused by diffusely-reflected light from powdered toner. | 02-19-2009 |
20090121162 | TECHNIQUE TO REMOVE SENSING ARTIFACTS FROM A LINEAR ARRAY SENSOR - Disclosed is a method and system for calibrating an image capturing sensor. The method and system include generating a test pattern on an image receiving device and measuring one or more colorimetric properties of the test pattern with an image sensor. The disclosed method and system measure the test pattern with the image sensor located in two or more different cross-process positions to determine an independent uniformity profile for the image sensor and the image rendering process. | 05-14-2009 |
20090231382 | Systems and Methods For Reducing Process Direction Registration Errors Of A Printhead Using A Linear Array Sensor - Systems and methods are provided for detecting process direction registration errors in a printer. The errors are detected by analyzing a metric of a dash minimum response obtained from a test pattern. The test pattern contains dashes. At least one dash is shifted in the process direction in relation to another dash. | 09-17-2009 |
20090265950 | REGISTRATION SYSTEM FOR A WEB PRINTER - An apparatus prints on a continuous web moving in a process direction. A fiducial marker prints on a portion of the web a repeating pattern of fiducial marks at a predetermined spacing along the process direction. At least two printing stations are operatively disposed downstream of the fiducial marker, each printing station including a printhead for placing marking material suitable for a partial image on the web. A photosensor reads a fiducial mark on the web moving relative to the printing station. | 10-29-2009 |
20090284762 | REDUCING PRINTHEAD PROCESS COLOR NON-UNIFORMITIES IN A DIRECT MARKING DEVICE - What is disclosed is a novel system and method for reducing process color banding due to printhead non-uniformities in a direct marking device. In one example, a first measurement of a printhead spatial non-uniformity is obtained along a first line in a color space which produces a spatial uniformity when a target primary color is printed alone. A first spatial tone reproduction curve is generated. A second measurement of the printhead spatial non-uniformity is obtained along a second line in color space in a coverage area of a process color which maximally changes a halftone structure of the target primary color. A second spatial TRC is generated. The first and second spatial TRCs are combined using a weighted average which balances the primary and process colors. A modified spatial TRC is generated. The printhead is adjusted at a location of the target primary color according to the modified spatial TRC. | 11-19-2009 |
20100123752 | Printhead Registration Correction System and Method for Use with Direct Marking Continuous Web Printers - A registration system for use with an imaging device includes sensors for detecting a web speed and a web tension of a moving web and a control system configured to generate a first timing offset for at least one marking station based on the detected web speed and web tension. An image sensor is configured to generate a signal indicative of a position of a marking material applied to the moving web by at least one of the marking stations. The control system is configured to generate a second timing offset for the at least one marking station based on the position of the marking material indicated by the third signal, and to adjust an actuation time for the at least one marking station using the first timing offset and the second timing offset. | 05-20-2010 |
20100231942 | METHODS AND SYSTEMS ACHIEVING PRINT UNIFORMITY USING REDUCED MEMORY OR COMPUTATIONAL REQUIREMENTS - Engine response curves (RCs) can be used for streak compensation for printed documents. A feedback control paradigm can be included to effect RC compensation. Singular Value Decomposition (SVD) can be used to represent each RC in the collection of spatial RC data as a linear combination of basis vectors. RCs are approximated by selecting the first few basis vectors, the approximation aiding in noise rejection and reducing computation in the controller by reducing dimensionality of the RC data from gray levels to the number of SVD bases selected. An optimal subset of RCs is selectable from the set of approximated RCs by clustering the SVD weights, the clustered SVD weights producing TRCs that span all engine response RCs generated by a printer. Compensation RCs are constructible using reduced number of bases and clustered SVD weights. | 09-16-2010 |
20100232652 | System And Method For Adjusting Operation Of Printheads In An Ink Printing Device - A method evaluates image quality in an ink printing system and generates data values for altering the operation of the ink printing system. The method includes generating an ink image on an ink image receiving member that corresponds to a digital image stored in the ink printing system, generating a scanned image signal corresponding to the ink image, generating firing signal waveform adjustments and image data adjustments with reference to the scanned image signal corresponding to the ink image, and operating a printhead in an ink imaging system with reference to the firing signal waveform adjustments and the image data adjustments. | 09-16-2010 |
20100245455 | METHOD AND SYSTEM FOR DETECTING PRINT HEAD ROLL - A method of detecting print head roll begins with the formation of a test pattern on an image receiving surface. The test pattern includes a plurality of marks arrayed across the image receiving surface in a cross-process direction with each mark in the plurality being formed by a different nozzle of a print head. The cross-process direction positions of each mark in the plurality of marks are then detected; and the detected cross-process direction positions are correlated to a print head roll value for the print head. | 09-30-2010 |
20100329756 | DUPLEX WEB PRINTER SYSTEM REGISTRATION TECHNIQUE - A system and method for achieving registering of side | 12-30-2010 |
20110025743 | PAPER SKEW DETECTION SYSTEM - A system and method that enables web paper skew detection by monitoring print head motor position. An inline full width array sensor actively tracks the alignment of the print heads across the print zone and actively moves the heads to maintain alignment. If the paper starts to skew across the print zone, a color misregistration error will be detected and the print units will be moves with respect to each other to maintain alignment. The absolute position of the print heads can be monitored by tracking the steps sent to each motor to maintain alignment. | 02-03-2011 |
20110116123 | System And Method For Attenuating Rotating Member Contamination Affecting Uniformity Measurements In An Inkjet Imaging Device - A method enables an inkjet printing system to attenuate image noise in an image of a test strip obtained as print media bearing the test strip travels over a roller in the printing system. The method includes illuminating blank media as the media travels over a rotating member, generating electrical signals corresponding to light reflected by the blank media as the blank media travels over the rotating member, converting the electrical signals to image data of the blank media, printing a test strip on media, illuminating the media as the media on which the test strip is printed travels over the rotating member, generating electrical signals corresponding to light reflected by the media as the media on which the test strip is printed travels over the rotating member, converting the electrical signals to image data of the media on which the test strip is printed, modifying the image data of the media on which the test strip is printed with the image data of the blank media, and storing the modified image data in memory. | 05-19-2011 |
20110187777 | Ink Drop Position Correction In The Process Direction Based On Ink Drop Position History - A method compensates for changes in drop velocity of drops emitted by inkjets in a printhead of an ink jet imaging device. The method includes adjusting image data used to generate firing signals for an inkjet ejector in a printhead of an inkjet imaging device with an initial ink drop correction parameter, adjusting a portion of the adjusted image data with another ink drop correction parameter in response to the portion of the adjusted image data corresponding to a predetermined firing pattern mask, generating firing signals for the inkjet ejector from the adjusted image data, and transmitting the generated firing signals to the inkjet ejector in the printhead. | 08-04-2011 |
20110242186 | Test Pattern Effective For Coarse Registration Of Inkjet Printheads And Method Of Analysis Of Image Data Corresponding To The Test Pattern In An Inkjet Printer - A test pattern printed by printheads in an inkjet printer enables image analysis of the test pattern that identifies positions of the printheads and the inkjets operating in the printheads. The test pattern includes a plurality of arrangements of dashes, each arrangement of dashes having a predetermined number of rows and a predetermined number of columns, each dash in a row of dashes in the arrangement of dashes being separated by a first predetermined distance and each dash in a column of dashes in the arrangement of dashes being separated by a second predetermined distance, each dash in a column of an arrangement of dashes being ejected by a single inkjet ejector in a printhead of the inkjet printer, and a plurality of unprinted areas interspersed between the plurality of arrangements of dashes. | 10-06-2011 |
20110242187 | Test Pattern Effective For Fine Registration Of Inkjet Printheads And Method Of Analysis Of Image Data Corresponding To The Test Pattern In An Inkjet Printer - A method analyzes image data corresponding to a test pattern generated on an image receiving member by a printer to identify positions for and registration between printheads in the printer. The method includes identifying a process direction position for each row of dashes in a plurality of rows of dashes in image data of a test pattern printed on an image receiving member, the test pattern being formed by each printhead in a printer forming at least one dash in each row of dashes in the plurality of rows of dashes, identifying a center of each dash in a cross-process direction, identifying an inkjet ejector that formed each dash in the row of dashes, identifying a process direction position for each printhead in the printer, identifying a cross-process displacement for each column of printheads, identifying a stitch displacement in the cross-process direction between neighboring printheads in a print bar unit that print a same color of ink, and operating an actuator to move at least some of the printheads in the printer with reference to the identified process direction positions, cross-process displacements, and the identified stitch displacements. | 10-06-2011 |
20110243581 | COLOR REGISTRATION STRATEGY FOR PREPRINTED FORMS - A computer-implemented method for performing color registration on template media having template markings thereon. The method comprising sensing the template media using a linear array sensor to obtain first image data; printing a test pattern on the template media; sensing the template media along with the test pattern printed thereon to obtain second image data; transforming the first image data and the second image data into an absorbance space to obtain a first absorbance and a second absorbance, respectively; calculating a difference between the first and the second absorbances to obtain an output absorbance; transforming the output absorbance into a reflectivity space to obtain an output data; determining a process direction misregistration and a cross-process direction misregistration from the output data; and adjusting a cross-process position and a process position of print heads based on the process and cross-process direction misregistration to provide accurate color registration on subsequent template media. | 10-06-2011 |
20110243636 | System And Method For Operating A Web Printing System To Compensate For Dimensional Changes In The Web - A method enables changes in the operation of a web printing system in response to web dimensional changes being detected. The method includes identifying a cross-process dimensional change in a web moving through a printing system, comparing the identified cross-process dimensional change to a predetermined threshold, and changing operation of a component in the web printing system in response to the cross-process dimensional change exceeding the predetermined threshold. | 10-06-2011 |
20110279503 | Method And System For Measuring And Compensating For Process Direction Artifacts In An Optical Imaging System In An Inkjet Printer - A printer operating method enables a controller to identify process direction errors in an optical imaging system. The method includes identifying a printhead roll error for each printhead in a plurality of printheads in a printer, moving each printhead by an amount that corrects the printhead roll error for the corresponding printhead, generating a plurality of dashes on media with the plurality of printheads as the media moves past the plurality of printheads, identifying a position for each dash in the process direction from image data of the plurality of dashes on the media, identifying a displacement in the process direction for each optical detector in a linear array of optical detectors used to generated the image data of the plurality of dashes, the displacement being identified with reference to the identified positions for the dashes, and operating the printer to compensate for the identified displacements of the optical detectors. | 11-17-2011 |
20110279504 | Method And System For Measuring And Compensating For Sensitivity And Backlash In Electrical Motors That Laterally Move Printheads In A Continuous Web Inkjet Printer - A method of operating a printer enables a controller in the printer to operate electrical motors for aligning printheads in the printer with greater accuracy. The method includes generating a test pattern on media with a plurality of printheads, identifying a first position for each printhead in the plurality of printheads from test pattern image data, operating an electrical motor operatively connected to one of the printheads to move the printhead in a first direction in the cross-process direction by a predetermined distance, generating a second test pattern on the media, identifying a second position for each printhead, comparing the second position of the printhead with the first position of the printhead to measure a distance moved by the printhead, identifying a first calibration parameter with reference to the predetermined distance and measured distance, and operating the electrical motor with reference to the first calibration parameter. | 11-17-2011 |
20110279505 | Method For Identifying And Verifying Dash Structures As Candidates For Test Patterns And Replacement Patterns In An Inkjet Printer - A method compensates for changes in drop velocity of drops emitted by inkjets in a printhead of an ink jet imaging device. The method includes operating inkjet ejectors in a plurality of printheads to eject ink in a pattern of structured dashes on an image receiving member, the structured dashes corresponding to a predetermined image data pattern, generating image data corresponding to the pattern of structured dashes on the image receiving member, identifying a process direction correction parameter for each ejector in the plurality of printheads with reference to the generated image data, modifying image data to be printed by the plurality of printheads with reference to the process direction correction parameter identified for at least one of the ejectors, and operating the plurality of printheads with reference to the modified image data. | 11-17-2011 |
20110279513 | Method And System For Printhead Alignment To Compensate For Dimensional Changes In A Media Web In An Inkjet Printer - A method enables a controller to align printheads in a printer. The method includes identifying a first cross-process position for each printhead in a plurality of printheads in a printer with reference to image data of a test pattern printed by the plurality of printheads on a media substrate, identifying a second cross-process position for each printhead in the plurality of printheads, calculating a printhead cross-process position error between the identified first cross-process position and the identified second cross-process position for each printhead, comparing a maximum printhead cross-process position error to a predetermined threshold, and operating a plurality of actuators with reference to the calculated printhead cross-process position errors to reposition the printheads in the plurality of printheads in response to the maximum printhead cross-process position error being equal to or less than the predetermined threshold. | 11-17-2011 |
20120113184 | METHOD AND SYSTEM FOR DETECTING PRINT HEAD ROLL - A method of detecting print head roll begins with the formation of a test pattern on an image receiving surface. The test pattern includes a plurality of marks arrayed across the image receiving surface in a cross-process direction with each mark in the plurality being formed by a different nozzle of a print head. The cross-process direction positions of each mark in the plurality of marks are then detected; and the detected cross-process direction positions are correlated to a print head roll value for the print head. | 05-10-2012 |
20120206530 | METHOD AND SYSTEM FOR PRINTHEAD ALIGNMENT TO REDUCE OR ELIMINATE BANDING ARTIFACTS FOR INTERLACED PRINTHEADS - A method for aligning printheads, some of which are arranged in an overlapped configuration, in a printer has been developed. The method includes identifying a stitch error for each color station in a plurality of color stations in the printer. The stitch error is identified with reference to shrinkage of a print medium as the print medium passes the plurality of color stations. A portion of the stitch error is used to move at least one printhead in the color station corresponding to the stitch error to compensate for a banding issue caused by the overlapped printhead configuration. All or part of the stitch error may also be applied to other printheads in the color station to compensate for possible color to color registration issues. | 08-16-2012 |
20120206531 | TEST PATTERN LESS PERCEPTIBLE TO HUMAN OBSERVATION AND METHOD OF ANALYSIS OF IMAGE DATA CORRESPONDING TO THE TEST PATTERN IN AN INKJET PRINTER - A method generates a test pattern on an image receiving member that is less perceptible to human observation, but still detectable by an imaging device within a printer. A method implemented in the printer analyzes image data of the dashes in the test pattern that were randomly distributed in the process direction within an area of the image receiving member to identify positions for printheads in the printer and detect missing inkjets in the printheads. | 08-16-2012 |
20120243928 | IDENTIFYING EDGES OF WEB MEDIA USING TEXTURAL CONTRAST BETWEEN WEB MEDIA AND BACKER ROLL - A computer-implemented method for identifying the edges of web media transported on a movable transport surface includes sensing, using a linear array sensor positioned along a process path of a web, the web media and the movable transport surface to obtain image data representative of variations in optical textural properties of the web media and variations in optical textural properties of the movable transport surface, wherein the variations in the optical textural properties of the movable transport surface are different from the variations in the optical textural properties of the web media; and processing the image data to determine differences between the variations in the optical textural properties of the web media and the variations in the optical textural properties of the movable transport surface to identify an edge of the web media. | 09-27-2012 |
20120314001 | Method And System For Actuating Redundant Electrical Motors To Move Printheads Laterally And Improve Reliability In A Continuous Web Inkjet Printer - A method of operating a printer enables a controller in the printer to operate electrical motors to move printheads in the printer for longer periods of time before maintenance is required. Each printhead in the printer is operatively connected to an electrical motor for movement of the printhead and the printheads are organized in groups with each group being operatively connected to an electrical motor for movement of the group. By selectively designating printheads as being moveable or fixed, electrical motors that fail to move a printhead can be taken out of operation and an electrical motor that moves the printhead group used instead to continue printing operations without requiring a service call for replacement of the failed motor. | 12-13-2012 |
20130021398 | Method and System for Aligning Printheads that Eject Clear Ink in an Inkjet Printer - A method enables an operator to detect misalignment of printheads that eject clear ink in an inkjet printer. The method prints a first test pattern with a first color of ink and then prints a second test pattern of clear ink on top of the first test pattern. The ink of the first and the second test patterns is then spread to enable the clear ink to be dispersed in interstitial spaces in the ink of the first color. An operator is then able to detect the spatial relationship of predetermined marks in the second test pattern to predetermined marks in the first test pattern. The predetermined marks of the first and the second test patterns are arranged to enable an operator to detect a misalignment distance and the inkjet printer uses the misalignment distance entered by the operator to adjust the alignment of the printheads that eject clear ink. | 01-24-2013 |
20140015909 | System and Method for Aligning Duplex Images Using Alignment Marks - A system and method for adjusting a transport path length of a continuous web of recording media in a printing system printing duplex images. The method includes detecting alignment marks, for instance top of form (TOF) marks, on the continuous web of print media and adjusting the path length to provide substantially accurate registration of first and second images on opposite sides of the web for duplex imaging. The system to adjust path length includes idler rollers movable with respect to turnbar rollers. | 01-16-2014 |
20140028747 | System and Method for Spreading Ink on a Media Web - A leveling and spreading system has been developed that enables the speed and position of the web to be determined from a sensor on a first roller. In a duplex print process, the first roller also reduces a temperature of the media web and an ink image printed in the first side print operation to within a first predetermined temperature range. A second roller modulates the temperature of the media web and ink ejected onto the media web immediately before the web enters the leveling and spreading system to within a second predetermined temperature range to enable uniformity of the ink and web temperatures for spreading the ink in a nip formed with a third roller. | 01-30-2014 |
20140139578 | Method And Apparatus For Alignment Of A Low Contrast Ink Printhead In An Inkjet Printer - In an inkjet printer, a first printhead forms a first mark on a print medium using a high-contrast ink. A second printhead forms a second mark on the first mark using a low-contrast ink. The printer generates image data of the low-contrast ink mark and the high-contrast ink, and a controller in the printer identifies a cross-process direction offset between the first printhead and the second printhead with reference to a distance between the center of the first mark and the second mark in the image data. | 05-22-2014 |
20140139579 | SPARSE TEST PATTERNS IN PRINTED DOCUMENTS FOR IDENTIFICATION OF INKJET AND PRINTHEAD PERFORMANCE IN A PRINTER - A method for operating an inkjet printer to identify inoperable inkjets includes ejecting ink drops of a first color onto an image receiving surface to impose a control pattern on a document zone in addition to an ink image generated in the document zone. A density of the control pattern in the document zone changes at a rate that is at or less than a predetermined threshold. The method includes generating scanned image data of a portion of the control pattern on the image receiving surface and identifying a performance parameter corresponding to inkjets and printheads in the printer. | 05-22-2014 |
20140139851 | Compensation For Alignment Errors In An Optical Sensor - A method of operating a printer to detect errors in an optical sensor includes forming a printed line across a first side of a print medium and generating first image data corresponding to the printed line with the optical sensor. The optical sensor generates second image data of the second side of the print medium as the print medium passes the optical sensor a second time. A detect in the optical sensor is identified with reference to a difference between process direction alignments of the line in the first image data and the second image data. | 05-22-2014 |
20140146102 | System And Method For Full-Bleed And Near Full-Bleed Printing - A method of operating a printer includes identifying a region of a print medium located between marks formed by a first plurality of inkjets in the printer and an edge of the print medium. The printer activates a second plurality of inkjets to print ink drops into the region during a printing operation. The method enables full-bleed or near full-bleed printing for different media sizes. | 05-29-2014 |
20140146329 | System And Method For Page Alignment In A Printer - A method for printing on a continuous print medium having a plurality of pages includes identifying a location of a feature in image data that are generated from a portion of a first page in the print medium. The method includes modifying a time of operation of a marking unit to form an image on each page in the plurality of pages at a predetermined distance from the edge of each page with reference to the location of the identified feature in the image data. In one configuration, the method enables precise placement of printed images over preprinted forms. | 05-29-2014 |
20140168301 | System And Method For Eliminating Background Image Data In Ink Images In An Inkjet Printer - An inkjet printer is configured to capture image data of a bare rotating imaging surface and use the image data of the bare rotating imaging surface to remove noise from subsequent images of printed ink on the rotating imaging surface. A controller in the printer is configured to measure cross-correlations between margins in the bare rotating imaging surface image data and margins in the subsequent images of printed ink to identify areas of alignment between the image data of the bare rotating imaging surface and the subsequent images of printed ink. The data in the areas in the image data of the bare rotating imaging surface that are aligned with areas in the subsequent images are used to remove the background noise produced by structure in the rotating imaging surface. | 06-19-2014 |
20140168304 | System And Method For Imaging And Evaluating Coating On An Imaging Surface In An Aqueous Inkjet Printer - An inkjet printer is configured to apply a coating material to an imaging surface before an ink image is formed on the surface. At least one optical sensor generates image data of the coating on the imaging surface and identifies a thickness of the coating material. Components of the coating material applicator can be adjusted to keep the thickness of the coating material within a predetermined range. | 06-19-2014 |
20140168312 | SYSTEM AND METHOD FOR IMAGING AND EVALUATING PRINTING PARAMETERS IN AN AQUEOUS INKJET PRINTER - An aqueous inkjet printer is configured to evaluate and adjust multiple components within the printer with reference to image data of the surface of a rotating member obtained at different times during a single print cycle. The print cycle can be performed in a multiple pass manner to enable a single optical sensor to be used for generation of the image data. Alternatively, the print cycle can be performed in a single revolution of the rotating member and multiple optical sensors positioned about the rotating member to generate the image data. | 06-19-2014 |
20140198146 | System And Method For Process Direction Registration Of Inkjets In A Printer Operating With A High Speed Image Receiving Surface - A method for process direction registration in an inkjet printer includes ejecting ink drops from a first inkjet at less than a maximum operating rate onto an image receiving surface moving in a process direction. The method includes generating image data samples of the image receiving surface including the ink drops. The method further includes identifying a center of the ink drops in the process direction with reference to the image data samples and storing a time offset value in a memory to correct an identified process direction offset between the identified center of the ink drops and another identified center of ink drops that are ejected by another inkjet. | 07-17-2014 |