Hewlett-packard Development Company, L.p.

Xavier Quintero Ruiz

Leticia Rubio

Utpal Kumar Sarkar

Raul Rodriguez Alonso

Marcos Casaldaliga

Carmen Blasco Cortes

Roma Segura Fabregas

Marti Rius Rossell

David Ramirez Muela

Alex Andrea Tallada

Andreas Muller

Miguel Angel Lopez

Montserrat Solano Pallarol

Carles Carmona Calpe

Carmen Blasco

David Vendrell Tornero

David Gaston Llado

Manuel Agudo Acemel

Luis Garcia-Maurino

Mireia Garcia

Luis Garcia-Maurino Simon

Utpal Kumar Sarker

Mireia Garcia Ferrer

Maria Vila Abad

Examples relate to computer-implemented methods for a printing system comprising a printhead, and to printing systems. A method for a printing system comprises retrieving a stored first offset applied to the printhead to align the printhead, the first offset determined based on a first user input signal; and further aligning the printhead according to a further offset determined based on a further user input signal, the further offset indicating a difference from the first offset.

Printhead alignment

The method may comprise depositing print agent of a particular color onto a printable substrate to form a patch of print agent. It may comprise directing radiation from a plurality of radiation sources onto the patch of print agent and onto the printable substrate. Also, may comprise detecting, using a sensor, radiation from the plurality of radiation sources which has been reflected from the printable substrate and radiation from the plurality of radiation sources which has been reflected from the patch of print agent. Further, may comprise measuring, for each of the plurality of radiation sources, an intensity of the radiation reflected from the printable substrate and an intensity of the radiation reflected from the patch of print agent. Also, may comprise selecting, based on the measured intensities, a radiation source of the sources to be associated with the print agent of the particular color.

Determining reflected light intensities of light sources

Certain examples describe a method of calibrating a printer and a printing system. An interferential pattern is printed in the form of a print calibration image on a print medium. Data representative of the interferential pattern as printed on the print medium is detected using an optical sensor. The printer is calibrated based on the captured data. The interferential pattern is based on a waveform that varies in amplitude along an axis perpendicular to a printing axis under calibration and has repeated sets of multiple patterns based on the waveform, the repeated sets having a varying pattern spacing in the printing axis under calibration.

Interferential patterns for printer calibration

A method of printing on a printable medium is disclosed. The method of printing may use a print head having a plurality of nozzles. The printable medium may have a leading edge and a defined zone adjacent to the leading edge. The print head may deposit print agent onto the printable medium via the plurality of nozzles during successive printing passes. The method may comprise printing outside, and not within, the defined zone on the printable medium using a first subset of nozzles of the plurality of nozzles. The method may further comprise printing within, and not outside, the defined zone on the printable medium using a second subset of nozzles of the plurality of nozzles.

Printing within defined zones

A circuitfor controlling a plurality of fluid dispense nozzles(N), the circuitto change an order in which the fluid dispense nozzles(N) are actuated.

Nozzle firing order controller

A printing apparatus comprises a printhead and a controller. The printhead includes dies, each die comprising rows of nozzles, wherein, in an overlapping region, the rows of nozzles of two dies overlap in a first direction, in which a relative movement between the printhead and a print medium takes place during operation of the printing apparatus. The controller is to apply a first weaving mask to a first row of nozzles of a first die and a second weaving mask to a second row of nozzles of the first die, the second weaving mask being different from the first weaving mask, the weaving masks defining, independent of print data, which of the nozzles of the corresponding row are to be used for printing in the overlapping region.

Applying first and second weaving masks

A method of printing is disclosed. The printing may involve printing on a printable medium using a print head having a plurality of nozzles, the printable medium having a leading edge and a defined zone adjacent to the leading edge. The print head may be to deposit print agent onto the printable medium via the plurality of nozzles during successive printing passes. The method may comprise: during a first printing pass, depositing print agent from a subset of the plurality of nozzles onto the printable medium outside the defined zone. The method may further comprise: advancing the printable medium by a defined distance. The method may further comprise: during a second printing pass, depositing print agent from a subset of the plurality of nozzles onto the printable medium within the defined zone.

Depositing print agent

Print apparatus is controlled to execute a print operation comprising a plurality of print sweeps onto a print zone of a print substrate and a corresponding plurality of print advances of the print substrate between successive print sweeps. Print apparatus is controlled to execute an intermediate cutting operation between a pre-cut print sweep and a successive post-cut print sweep of the plurality of print sweeps.

Cutting print substrates

Misalignments of a 3d printing device may be detected by providing a reference pattern in a print zone of the 3d printing device, wherein the reference pattern comprises a plurality of reference marks, printing a test pattern on the reference pattern by means of the 3d printing device, and comparing the test pattern with the reference marks.

Misalignment detection for a 3D printing device

A method includes printing an image on substrate by a printhead using ultraviolet (UV) curable ink. The method includes selectively applying a first amount of UV radiation by a first region of a light source to a first area of the image after a first amount of time passes from printing the first area to form a first gloss level area having a glossy finish. The method also includes selectively applying a second amount of UV radiation by a second region of the light source to a second area of the image after a second amount of time passes from printing the second area to form a second gloss level area having a matte finish. At least one of the second amount of UV radiation is greater than the first amount of UV radiation and the first amount of time is greater than the second amount of time.

Formation of gloss level areas having a glossy finish and a matte finish in an image

In some examples, a printer includes neighboring nozzle arrays extending across a print zone, each nozzle array of the neighboring nozzle arrays extending along an axis and comprising a first section of nozzles and a second section of nozzles, wherein the second sections of the neighboring nozzle arrays overlap defining an overlap region and the first sections of the neighboring nozzle arrays define non-overlap regions. A controller is to cause printing of a test pattern using the neighboring nozzle arrays, the test pattern comprising a first pattern printed by the second sections of the neighboring nozzle arrays in the overlap region, and a reference pattern printed by a first section of the first sections of the neighboring nozzle arrays in a non-overlap region of the non-overlap regions, receive detected characteristics of the printed test pattern, compare the characteristics of the printed test pattern in the overlap region and in the non-overlap region, and derive alignment information based on the comparing.

Printer and computer-implemented process for controlling a printer

In one example, a wedge shaped carriage to carry a printhead back and forth over a print substrate during printing.

Printhead carriage

In one example, a carriage to carry a printhead back and forth over a print substrate includes an inboard part to hold the printhead and an outboard part to inhibit the flow of air under the carriage when the carriage is moving back and forth over the print substrate.

Inhibiting air flow

According to one example, there is provided a method of determining an alignment characteristic of a printhead die installed in a printer. The method comprises controlling the printer to print a predetermined pattern using the printhead die and determining, through analysis of the distance between features of the printed predetermined pattern, alignment characteristics of the printhead die.

Determining an alignment characteristic based on distances of features of a printed pattern

A method of controlling a printer is disclosed, the printer including a number of print heads extending across a print zone, and each print head including at least one nozzle array extending in a direction of a print head axis. Each nozzle array comprises a center section of nozzles and side sections of nozzles, wherein the side sections of neighboring nozzle arrays overlap defining an overlap region and the center sections of the nozzle arrays define non-overlap regions. The method includes: printing a test pattern using at least two nozzle arrays, the test pattern comprising an interferential-type pattern printed by the side sections of the nozzle arrays in the overlap region and a reference pattern printed by the center sections of the nozzle arrays in the non-overlap regions; detecting characteristics of the printed test pattern; comparing the characteristics of the printed test pattern in the overlap region and in the non-overlap region; and deriving information concerning the alignment of nozzle arrays from the comparison

Growing community of inventors

Sant Cugat del Valles, Spain

Xavier Quintero Ruiz