Xerox Corporation

Eastman-kodak Company

Nexpress Solutions, Inc.

Thomas Allen Henderson

Matthias Hermann Regelsberger

Richard George Allen

Nancy Beth Goodman

Gary Allen Denton

John F Knapp

Chung-Hui Kuo

Peter A Crean

Hwai-Tzuu Tai

Majid Rabbani

Lingappa K Mestha

Eric Karl Zeise

Christopher B Liston

Patrick Metzler

Tracy Eugene Thieret

Karlheinz Walter Peter

Terry Anthony Wozniak

Norman W Zeck

Stacy M Munechika

Cumar Sreekumar

Michael A Butler

Stephen J Farnand

Methods for operating a toner printer are provided. In one method a toner image is printed according to first printing instructions. An amount of toner in a target area of the toner image is determined and second printing instructions are generated causing the toner printer to print at least one subsequent toner image based upon the determined amount of first toner.

Method of operating a printer with unfused toner process control

Toner printers are provided. In one printer a toner image is printed according to first printing instructions. An amount of toner in a target area of the toner image is determined and second printing instructions are generated causing the toner printer to print at least one subsequent toner image based upon the determined amount of first toner.

Printer with unfused toner process control system

A method is provided of compensating for periodic non-uniformity in an electrophotographic printer with a rotatable imaging component, and a runout sensor for measuring the distance between a first reference point and the surface of the rotatable imaging component along a first reference axis. An image signal representing an image to be produced on a receiving member by the printer is received. The rotatable imaging component is rotated. While the rotatable imaging component is rotating, the distance for the rotatable component is measured using the runout sensor. A correction value corresponding to the measured distance is automatically determined using a processor. The image data corresponding to the measured distance are automatically adjusted with the correction value using the processor. Toner corresponding to the adjusted image data is deposited on the receiver using the rotatable imaging component.

Compensating for periodic nonuniformity in electrophotographic printer

Toner sensor modules are provided. In one aspect, a toner sensor module has a first light source emitting a first light, a first light sensor that generates a sensed light signal that is indicative of a sensed light, and a frame. The frame positions the light source to illuminate a target area from a first side a plane that is normal to the target area so that illuminated portions of any toner particles at the target area direct a reflected a portion of the first light into the first side and positioning the first light sensor on the first side of the plane to which toner particles at the target area direct the reflected portion of the first light.

Toner sensor module

A method of adjusting a level of liquid to be deposited on a print media includes providing an image processing system. Image data for a page of a print job and information regarding a printing system to be used to deposit the liquid on the print media during a printing operation is provided to the image processing system. The image data for the page of the print job is converted into a bitmap appropriate for analysis of risk of excessive inking related print defects using the image processing system. The overall risk score is determined to be acceptable or unacceptable. The bitmap is released for printing when the overall risk score is acceptable. The image data for the print job page is modified when the overall risk score is unacceptable.

Print content dependent adjustment of printed liquid

Non-uniformity of a rotatable electrophotographic imaging component is compensated. The component has an intentional periodic variation that produces density variations in a test target. The angular position on the component of the intentional variation is correlated with the amount of an unintentional variation at several points to produce a non-uniformity map. An image signal with multiple regions of data is received. For each region, the angular position of the intentional variation in that region is determined, and the non-uniformity map is used to determine the correction required for the unintentional variation. The image data in the region are adjusted to compensate, and corresponding toner is deposited.

Electrophotographic non-uniformity compensation using intentional periodic variation

A method of providing calibration data for a printer includes printing a calibration target using the printer. The target includes a plurality of patch sets, each including a plurality of test patches, each patch having a respective color. Scanned patch data for one of the sets are received from a spot scanner. The scanned patch data values are compared to respective aims to determine a reproduction error value for the scanned patch set. A processor automatically determines which of the sets should be scanned next using the calculated reproduction error value. The process is repeated until all sets have been scanned, or until the reproduction error value is less than or equal to a selected threshold. Calibration data are automatically generated using the scanned patch data.

Providing calibration data for printer

A method is provided of determining the cause of artifacts in images produced by an electrophotographic (EP) printer. A reference image is printed and artifacts in it are detected. After printing normal images, a test image is printed and artifacts in it are detected. If a detected artifact in the test image does not correspond to a detected artifact in the reference image, a characteristic frequency spectrum of the artifact in the test image is determined. Run-out on rotatable imaging components is measured, and a characteristic frequency spectrum of each is determined. The test image spectrum is compared to each component spectrum to identify which component is causing the artifact.

Determining the cause of printer image artifacts

One or more printers or printing systems are connected to a scanning device. Each printer includes one or more color modules that are used during a printing operation. A printer prints a target for each color module or color channel. The printed targets are then scanned by the scanning device. The printed targets may be rotated to any angle and then scanned by the scanning device. The scanned raster data is processed by a controller to detect non-uniformities in at least one density image and to generate one or more correction profiles for the printer. When an image is to be printed, one or more controllers receive the image data and use the one or more correction profiles to correct or compensate for the non-uniformities during the exposure process.

Adaptive exposure printing and printing system

An in-line optical sensor assembly that measures optical reflection density on a printed sheet horizontally conveyed and supported by a paper transport section of a printer is provided. The sensor assembly includes a densitometer having frame provided with a pair of tapered blades that engage the moving printed sheet, a light source disposed on said frame that illuminates a portion of said printed sheet at a continuous intensity, and a photo-detector mounted on the frame and positioned to receive light from the light source that is reflected off said printed sheet. The optical sensor assembly also includes a mounting that floatably mounts the densitometer in a position over the printed sheet. The mounting can be formed from an opening in a cover plate of the paper transport section that slidably receives the densitometer such that the pair of tapered blades continuously engages the moving sheet in ski-like fashion due to the weight of the densitometer. The floating mounting arrangement maintains a constant, predetermined distance between the photo-detector of the densitometer and the illuminated portion of the moving printed sheet regardless of vertical movement of the printed sheet within said paper transport section.

In-line self spacing optical sensor assembly for a printer

A method for compressing a digital image having both saturated text and/or line art and pictorial imagery, the method comprises the steps of: receiving the digital image as blocks of pixels; analyzing the block content to determine if all or any combination of the saturated text and/or line art, pictorial imagery or other types of image data are present; assigning the saturated text and/or line art, the pictorial imagery, the other types of image data to one of a plurality of categories; compressing the block of saturated text and/or line art, if any, according to a first predetermined compression method; compressing the pictorial imagery, if any, according to a second predetermined compression method; compressing the other types of imagery, if any, according to other predetermined compression methods; and providing means of conveying the image categories to a decoder.

Method for compressing and decompressing digital having text

A method and apparatus for setting registration in a multicolor printing machine having a number of exposure devices for the digital production of color separations, the actions of setting up and combining the color separations being controlled, in order to set the registration, in such a way that accurate registered prints are achieved. According to the invention, in the event of a change in the toner profile, the influence of the toner profile on the registration is taken into account, by available influencing variables directly as the change is implemented.

Method and apparatus for setting registration in a multicolor printing machine based on a change in toner profile

A method for achieving multiple exposure levels for IOI (IMAGE-ON-IMAGE) xerography when imaging a second color through a first toner layer previously developed on the photoreceptive member. In the example illustrated the data from the previous image paths (magenta and yellow) is analyzed. If the signal indicates that a magenta or yellow bit is present, the cyan output bit information passes to the ROS unchanged, or at full intensity. If however, the magenta and yellow are not present, a modified pattern providing an appropriate reduced exposure signal is sent to the ROS. The process of laser attenuation is blended with halftoning logic to avoid image degradation due to the attenuation.

Using multiple digitally-produced exposure levels to compensate for

A method of encoding higher resolution edge information in lower resolution image information, so that the advantageous properties of both types of data can be used in binarization including the steps of receiving text/line art regions of the document image as binary pixels at a text/line art frequency selected to avoid aliasing effects at any edge pixels therein; receiving pictorial regions of the document image as continuous tone pixels, at a frequency lower than the text/line art frequency; applying an anti-aliasing filter to the text/line art regions, to replace some edge pixels with gray level pixels having M levels; converting the document image to a binary representation by converting each of the M levels in the text/line art regions to a binary representation reflecting correct edge position of the text/line art regions, and converting the contone pixels to a binary representation determined by a halftone pattern having N levels selected for the contone pixels.

Method of encoding high resolution edge position information in

A method of development control by storing a reference tone reproduction curve and sensing a relatively small segment of an arbitrary image on an imaging surface. The relatively small segment of the arbitrary image on the imaging surface is then converted into suitable density values, such as background, solid area, and halftone and a control responds to the density values to adjust the machine operation for print quality correction.

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Rochester, NY, United States of America

Thomas Allen Henderson