Hp Indigo B.v.

Hewlett-Packard Development Company, L.p.

Hewlett-Packard Indigo B.v.

Ran Waidman

Shlomo Harush

Gal Amit

Eyal Shelef

Tsafrir Yedid Am

Gregory Braverman

Sasi Moalem

Nir Guttman

Lior Katz

Yohanan Sivan

Matthew Donald Gaubatz

Tal Frank

Kobi Shkuri

Boris Oicherman

Sagi Yehonatan Refael

Oren Bengigi

Tsafrir Yedid-Am

Dmitry Iofe

Lena Gurevich

Tair Atzmon

Measures for use in calibrating a printing device. Historical dot gain linearization lookup table data for the printing device is processed. On the basis of the processed historical dot gain linearization lookup table data, a plurality of input points for a current dot gain linearization lookup table are dynamically determined. The printing device is calibrated according to the dynamically determined current dot gain linearization lookup table.

Dynamic dot gain lookup table generation

Examples of charging a photoconductive layer in an image forming apparatus are described. In one example, a method includes applying a charging voltage to the photoconductive layer and measuring surface voltages of the photoconductive layer at a plurality of positions on the photoconductive layer. Based on the measured surface voltages, a correction voltage profile is determined. The determined correction voltage profile includes at least a first correction voltage associated with a first position on the photoconductive layer and a second correction voltage associated with a second position, different to the first position, on the photoconductive layer. The method includes applying the first correction voltage to the photoconductive layer and applying the second correction voltage to the photoconductive layer.

Photoconductor charging uniformity correction

A method of adjusting an imaging apparatus comprises printing a set of test patches, the set of test patches comprising a solid color patch, a grey level patch and a substrate patch. The optical densities of the set of test patches are determined. The method comprises simultaneously correcting a solid optical density value (Solid OD), relating to the solid color patch and an associated grey level (LUT) value relating to the grey level patch.

Adjusting imaging apparatuses

In one embodiment, a processor-readable medium stores code representing instructions that when executed by a processor cause the processor to print a print job, and determine target color data for each sheet of the print job while printing the job. The instructions further cause the processor to continually save the target color data to a server for each sheet of the print job as each sheet is printed.

Printing with target color data

An apparatus to calibrate a printer. The apparatus comprises a controller to: control deposition of white printing material on media, the white printing material having an opacity of at least 55%; control deposition of non-white printing material on the white printing material; receive data for at least one sensed characteristic of the non-white printing material; and calibrate the printer using the received data for the at least one sensed characteristic of the non-white printing material.

To calibrate a printer

A printer () is disclosed. The printer has two scanners () in the paper path of the printer located after the print zone (). The two scanners are spaced apart from each other by a known distance A and overlap each other in a direction perpendicular to the media axis of travel. The two scanners capture a first and second image of the media.

Printer with two scanners

A spectrophotometer diagnosis system and a method for diagnosing a spectrophotometer, wherein at least one test patch is printed in proximity to at least one non-printed substrate patch, at least one value characteristic of the at least one test patch and/or the at least one substrate patch is measured using the spectrophotometer, and at least one diagnostic score for the spectrophotometer is determined based on the at least one measured value in comparison with a reference value.

Spectrophotometer diagnosis

A method includes forming a second set of printing dots on a photosensitive member by a printing dot applicator corresponding to image data of second portions of the image adjacent to first portions of the image. The second set of printing dots are formed on the photosensitive member after the first set of printing dots have been transferred from the photosensitive member. Thus, a merging of adjacent printing dots due to an electrical interaction there between on the photosensitive member is reduced.

Reduce merging of adjacent printing dots on a photosensitive member

An apparatus and method for use in capturing image data of an output of a printing device during a print run, the method comprising capturing a first portion of image data of a first spread, capturing a second portion of image data of a second spread, wherein the location of the second portion of image data on the second spread is different from the location of the first portion of image data on the first spread, and combining the first portion with the second portion to generate oversampled image data.

Capturing image data of printer output

Printing by determining target color values based on first color outputs, determining current color values based on current color outputs, and calculating color compensation values to compensate for a difference between the target color values and the current color values.

Printing with continuous color calibration

In an example implementation, a method of iterative calibration includes, in a first iteration, measuring first values of a calibration parameter, and determining first corrections for the measured first values. The method includes, in a next iteration, measuring next values of the calibration parameter that incorporate the first corrections. The first corrections are omitted from the next iteration measurements to provide pseudo iteration measurements, and the first iteration measurements are averaged with the pseudo iteration measurements. Second corrections are then determined based on the averaging.

Iterative calibration omitting first corrections from a next iteration

An embodiment of this disclosure involves printing color outputs on sheets, reading the color outputs and adjusting a calibration parameter.

Growing community of inventors

Rehovot, Israel

Ran Waidman