Abstract: Color registration errors are corrected for print jobs including periodic image content. Pixels values for a set of document pages are analyzed to identify the presence a periodic pattern of ink coverage having a repeat period. A first subset of document pages are printed and the resulting color registration errors are measured and analyzed to determine a periodic pattern of color registration errors. A repeating pattern of color registration correction values are determined corresponding to the periodic pattern of color registration errors. A second subset of the document pages is printed using the determined repeating pattern of color registration correction values.

Abstract: A method for correcting image plane registration errors for a multi-channel printing system that prints documents of a particular document-type classification having a variable number of pages. An image plane registration error database stores image plane registration error information characterizing image plane registration errors as a function of page number for each of a plurality of different page-count classifications. A page-count classification is determined for a document to be printed, and image plane registration correction values are determined for each page based on the stored image plane registration error information associated with the determined page-count classification, wherein the image plane registration correction values for each page are determined based on the stored image plane registration error information for the corresponding page number. The image data for each document page of the document is then printed responsive to the corresponding image plane registration correction values.

Abstract: A method for correcting image plane registration errors for a multi-channel printing system that prints documents of a particular document-type classification having a variable number of pages. An image plane registration error database stores image plane registration error information characterizing image plane registration errors as a function of page number for each of a plurality of different page-count classifications. A page-count classification is determined for a document to be printed, and image plane registration correction values are determined for each page based on the stored image plane registration error information associated with the determined page-count classification, wherein the image plane registration correction values for each page are determined based on the stored image plane registration error information for the corresponding page number. The image data for each document page of the document is then printed responsive to the corresponding image plane registration correction values.

Abstract: Color registration errors are corrected for print jobs including periodic image content. A first subset of document pages are printed and the resulting color registration errors are measured. The measured color registration errors are analyzed to identify the presence of a periodic pattern of color registration errors having a repeat period. A repeating pattern of color registration correction values are determined corresponding to the periodic pattern of color registration errors. A second subset of the document pages is printed using the determined repeating pattern of color registration correction values.

Abstract: A method and system for reducing tension fluctuations in a printing system are disclosed. A plurality of tension zones is defined in the printing system. Tension on the web in one tension zone is controlled independently of the tension on the web in the other tension zones. The printing system also includes at least one roller for each tension zone. The rollers receive tension control commands and control the amount of tension on the web in their respective tension zones. The printing system is used to print a first copy of the print job on the web and tension on the web in each tension zone is measured. Tension control adjustments are computed for each tension zone based on the tension measurements. The tension control adjustments are used to adjust the tension control commands to the rollers to print a second copy of the print job.

Abstract: A printing system including a plurality of printheads for printing on a web of media traveling along a web transport path, at least one of the printheads being configured to print at first and second print lines. A plurality of web transport rollers guide the web of media along the web transport path. At least some of the plurality of web transport rollers are constrained to have a roller circumference that is substantially equal to an integer fraction of a span of the web of media along the web transport path between two successive print locations in successive print heads. A span extension member provides an increased span of the web of media between the first and second print lines in a particular printhead such that the increased span is an integer multiple of the roller circumferences of the constrained web transport rollers.

Abstract: A method and system for reducing tension fluctuations in a printing system are disclosed. A plurality of tension zones is defined in the printing system. Tension on the web in one tension zone is controlled independently of the tension on the web in the other tension zones. The printing system also includes at least one roller for each tension zone. The rollers receive tension control commands and control the amount of tension on the web in their respective tension zones. The printing system is used to print a first copy of the print job on the web and tension on the web in each tension zone is measured. Tension control adjustments are computed for each tension zone based on the tension measurements. The tension control adjustments are used to adjust the tension control commands to the rollers to print a second copy of the print job.

Abstract: A method and system for reducing tension fluctuations in a printing system are disclosed. A plurality of tension zones is defined in the printing system. Tension on the web in one tension zone is controlled independently of the tension on the web in the other tension zones. The printing system also includes at least one roller for each tension zone. The rollers receive tension control commands and control the amount of tension on the web in their respective tension zones. The printing system is used to print a first copy of the print job on the web and tension on the web in each tension zone is measured. Tension control adjustments are computed for each tension zone based on the tension measurements. The tension control adjustments are used to adjust the tension control commands to the rollers to print a second copy of the print job.

Abstract: A method and system for reducing tension fluctuations in a printing system are disclosed. A plurality of tension zones is defined in the printing system. Tension on the web in one tension zone is controlled independently of the tension on the web in the other tension zones. The printing system also includes at least one roller for each tension zone. The rollers receive tension control commands and control the amount of tension on the web in their respective tension zones. The printing system is used to print a first copy of the print job on the web and tension on the web in each tension zone is measured. Tension control adjustments are computed for each tension zone based on the tension measurements. The tension control adjustments are used to adjust the tension control commands to the rollers to print a second copy of the print job.

Abstract: A method and system for reducing registration errors in a printing system are disclosed. A plurality of tension zones is defined in the printing system. Tension on the web in one tension zone is controlled independently of the tension on the web in the other tension zones. The printing system also includes at least one roller for each tension zone. The rollers receive tension control commands and control the amount of tension on the web in their respective tension zones. The printing system is used to print a first copy of the print job on the web and a plurality of registration errors is determined. Tension control adjustments are computed for each tension zone based on the registration errors. The tension control adjustments are used to adjust the tension control commands to the rollers to print a second copy of the print job, thereby reducing registration errors.

Abstract: A printing system including a plurality of printheads for printing on a web of media traveling along a web transport path, at least one of the printheads being configured to print at first and second print lines. A plurality of web transport rollers guide the web of media along the web transport path. At least some of the plurality of web transport rollers are constrained to have a roller circumference that is substantially equal to an integer fraction of a span of the web of media along the web transport path between two successive print locations in successive print heads. A span extension member provides an increased span of the web of media between the first and second print lines in a particular printhead such that the increased span is an integer multiple of the roller circumferences of the constrained web transport rollers.

Abstract: A method and system for reducing registration errors in a printing system are disclosed. A plurality of tension zones is defined in the printing system. Tension on the web in one tension zone is controlled independently of the tension on the web in the other tension zones. The printing system also includes at least one roller for each tension zone. The rollers receive tension control commands and control the amount of tension on the web in their respective tension zones. The printing system is used to print a first copy of the print job on the web and a plurality of registration errors is determined. Tension control adjustments are computed for each tension zone based on the registration errors. The tension control adjustments are used to adjust the tension control commands to the rollers to print a second copy of the print job, thereby reducing registration errors.

Abstract: A method for high-speed multi-color printing includes at least one high-resolution sensor array (23), wherein an output of the high-resolution sensor array is transmitted to a controller (19); at least one low-resolution sensor array (24); wherein the controller calculates a correction for stitch; wherein the controller, based on the calculated correction, adjusts a timing of image data provided to individual print elements comprising print stations (12) to aligned an output of the print elements; and wherein the low-resolution sensor array provides full page viewing.

Abstract: A method for aligning a photoconductor cartridge (200) in an electrophotographic device includes providing at least two holes in a first end of the cartridge. At least two pins (251) are provided in a frame of the electrophotographic device which mate with the holes in the first end of the cartridge when the cartridge is inserted in the electrophotographic device. A drive mechanism contacts a spherical bearing of a photoconductor of the cartridge and drives a pair of drive dogs. One drive dog is affixed to a spline on the drive mechanism and a second drive dog is affixed to the spherical bearing. At least one hole is provided in a second end of the cartridge. At least one pin is provided in a frame of the electrophotographic device which mate with the hole in the second end of the cartridge when the cartridge is inserted in the electrophotographic device.

Abstract: A multi-resolution imaging device (10) for a high-speed multi-color printer includes at least one high-resolution sensor array (23), wherein an output of the high-resolution sensor array is transmitted to a controller (19); at least one low-resolution sensor array (24); wherein the controller calculates a correction for stitch; wherein the controller, based on the calculated correction, adjusts a timing of image data provided to individual print elements comprising print stations (12) to aligned an output of the print elements; and wherein the low-resolution sensor array provides full page viewing.

Abstract: A multi-resolution imaging device (10) for a high-speed multi-color printer includes at least one high-resolution sensor array (23), wherein an output of the high-resolution sensor array is transmitted to a controller (19); at least one low-resolution sensor array (24); wherein the controller calculates a correction for stitch; wherein the controller, based on the calculated correction, adjusts a timing of image data provided to individual print elements comprising print stations (12) to aligned an output of the print elements; and wherein the low-resolution sensor array provides full page viewing.

Abstract: A method for high-speed multi-color printing includes at least one high-resolution sensor array (23), wherein an output of the high-resolution sensor array is transmitted to a controller (19); at least one low-resolution sensor array (24); wherein the controller calculates a correction for stitch; wherein the controller, based on the calculated correction, adjusts a timing of image data provided to individual print elements comprising print stations (12) to aligned an output of the print elements; and wherein the low-resolution sensor array provides full page viewing.

Abstract: A development system (10) for an electrophotographic printer (100) with multiple augers and containing a development roller (11) and a first channel (12) containing a feed auger (13) and developer (14), where the magnetic strength of the feed pole of the development roller increases in the direction of developer flow (18) in the first channel. This increase in magnetic field strength of the feed pole (50) ensures that a uniform layer of developer is formed on the development roller despite the volume of developer in the first channel decreasing along the length of the first channel in the direction of developer flow.

Abstract: A method and system for printing documents with one or more embedded security features is provided. Security features are embedded in the document by co-printing magnetic and non-magnetic toner on a receiver before fixation by a fixing station. The combination of magnetic and non-magnetic toners in the image results in image elements that easily show alteration or are undetectable by visual means.

Abstract: A method for transferring developer (14) to a development roller (11) in an electrophotographic printing process includes feeding developer from a first channel (12) to the development roller; releasing developer from the development roller to a second channel (15); and wherein a strength of a pickup field of a feed magnet (50) in the development roller increases in a direction of developer flow in the first channel.