Algird M Gudaitis

US Patent:

6364549, Apr 2, 2002

Filed:

Apr 27, 2000

Appl. No.:

09/564383

Inventors:

Christopher M. Lesniak - Vancouver WA
Algird M. Gudaitis - Vancouver WA

Assignee:

Hewlett-Packard Company - Palo Alto CA

International Classification:

B41J 342

US Classification:

400 74, 400582

Abstract:

A simple, yet accurate way of determining calibration values for correcting the characteristic sinusoidal feed errors of a printer or other recording device (such as a fax machine, plotter, etc. ). A sheet of calibration media is employed for facilitating the calculation of the calibration values. The sheet is used in a way that prevents the calibration media errors from affecting the calculation. In particular, the sheet of calibration media is fed twice through the printer, and position data is collected each time. The data is processed in a way that cancels the attendant calibration media errors so that the calculated calibration values precisely correct the characteristic sinusoidal feed errors of that printer.

US Patent:

6364551, Apr 2, 2002

Filed:

Feb 11, 2000

Appl. No.:

09/502427

Inventors:

Christopher M. Lesniak - Vancouver WA
Algird M. Gudaitis - Vancouver WA

Assignee:

Hewlett-Packard Company - Palo Alto CA

International Classification:

B41J 1142

US Classification:

400582, 400578

Abstract:

A method of controlling a media-advance drive motor of a printer in a manner that preserves accuracy in the incremental advances of print media between printing swaths, while optimizing throughput and accounting for variations in printer system response characteristics. A printer control algorithm commences each media-advance step by accelerating the media-advance drive motor to a maximum velocity. The motor is thereafter decelerated by controlling the drive voltage to the motor as needed to conform to a predetermined decaying velocity versus position function that is representative of a specimen system. The velocity versus position function is correlated to the required media position so that a media-advance motor following that function will arrive at a zero velocity at the precise instant that the media arrives at the position representing the end of its incremental advance.

US Patent:

6454474, Sep 24, 2002

Filed:

Nov 14, 2001

Appl. No.:

10/003163

Inventors:

Christopher M. Lesniak - Vancouver WA
Algird M. Gudaitis - Vancouver WA

Assignee:

Hewlett-Packard Co. - Palo Alto CA

International Classification:

B41J 1142

US Classification:

400582, 101484

Abstract:

A simple, yet accurate way of determining calibration values for correcting the characteristic sinusoidal feed errors of a printer or other recording device (such as a fax machine, plotter, etc. ). A sheet of calibration media is employed for facilitating the calculation of the calibration values. The sheet is used in a way that prevents the calibration media errors from affecting the calculation. In particular, the sheet of calibration media is fed twice through the printer, and position data is collected each time. The data is processed in a way that cancels the attendant calibration media errors so that the calculated calibration values precisely correct the characteristic sinusoidal feed errors of that printer.

US Patent:

6550884, Apr 22, 2003

Filed:

Jun 14, 2001

Appl. No.:

09/882573

Inventors:

Algird M Gudaitis - Vancouver WA
Christopher M Lesniak - Vancouver WA
Stephen A Smith - Ridgefield WA

Assignee:

Hewlett-Packard Development Co., L.P. - Houston TX

International Classification:

B41J 2938

US Classification:

347 16, 347 42, 347 43, 347 12, 347 14

Abstract:

Discussed herein is a method of positioning a printers drive roller relative to the printers printhead. The printhead has rows of individual print elements arranged to apply transverse dot rows to a print medium. To print at a desired location on the print medium, the printer initiates a first drive roller advance to the desired location, at a relatively fast slew speed. Assuming some overshoot or undershoot occurs, the printer then determines the actual position error of the drive roller, and selects a set of the printhead rows that correspond most closely in position to the desired print location. The printer then initiates a second drive roller advance, at a relatively slow speed, to position the selected group of printhead rows accurately over the desired print location on the print medium. These printhead rows are then used to perform the actual printing. The slow speed of the second drive roller advance ensures high positioning accuracy.

US Patent:

6568780, May 27, 2003

Filed:

Apr 30, 2001

Appl. No.:

09/845130

Inventors:

Christopher A. Schantz - Redwood City CA
Wen-Li Su - Vancouver WA
Algird M. Gudaitis - Vancouver WA

Assignee:

Hewlett-Packard Company - Palo Alto CA

International Classification:

B41J 2938

US Classification:

347 14, 347 17, 347 19

Abstract:

An environmental condition detection system for a hardcopy device, such as an inkjet printing mechanism, includes an environmental condition sensor having an optical property which changes in response to a change in an environmental condition, for instance humidity or temperature. The system also has an optical sensor which detects changes in the optical property and generates a signal for a controller that responds by changing an operating parameter of the hardcopy device. A hard copy device having such a environmental condition detection system is also provided, along with a method of determining an environmental condition within which a hardcopy device is operating.

US Patent:

6582052, Jun 24, 2003

Filed:

Sep 9, 2002

Appl. No.:

10/238860

Inventors:

Sam Sarmast - Vancouver WA
Tod S. Heiles - Vancouver WA
Algird M. Gudaitis - Vancouver WA

Assignee:

Hewlett-Packard Development Company, L.P. - Houston TX

International Classification:

B41J 29393

US Classification:

347 19, 347 43, 101486

Abstract:

A pen alignment method for a multi-pen printer is provided, the method including directing a first pen to print a first pattern of a first color, directing a second pen to print a second pattern of a second color in a predetermined relative alignment with the first pattern to form a test block, determining an actual hue of the test block via spectral analysis of the test block using a color sensor, and comparing the actual hue of the test block with an expected hue of the test block to determine whether the first and second pens are misaligned relative to each other, wherein the expected hue of the test block is the hue that would be detected if the first pen and second pen were correctly aligned.

US Patent:

6655778, Dec 2, 2003

Filed:

Oct 2, 2001

Appl. No.:

09/970196

Inventors:

Dan Arquilevich - Portland OR
Algird M. Gudaitis - Vancouver WA
Sam Sarmast - Vancouver WA
Tod S. Heiles - Vancouver WA

Assignee:

Hewlett-Packard Development Company, L.P. - Houston TX

International Classification:

B41J 29393

US Classification:

347 19, 347 14

Abstract:

A compact optical sensing system is used in hardcopy devices for scanning and/or printing images, for instance, using inkjet printing technology in desktop printing or in photographic printers appearing in grocery and variety stores. Several light emitting diodes (âLEDsâ) illuminate a sheet of print media, and one or more photodiodes receive light reflected from the sheet. The photodiode generates signals in response to the light received, and the hardcopy device uses these signals to adjust printing parameters for optimal print quality. Using a chip-on-board process, the bare silicon die for each component is wire bonded directly to a printed circuit board assembly, allowing at least four LEDs (blue, green, red and soft-orange) to be grouped closely together in a space smaller than that occupied by a factory-made, single-packaged LED. A calibrating system uses a white target covered for cleanliness by a windowed door which is opened/closed by a printhead carriage.

US Patent:

6659578, Dec 9, 2003

Filed:

Oct 2, 2001

Appl. No.:

09/969745

Inventors:

Algird M. Gudaitis - Vancouver WA
Sam Sarmast - Vancouver WA
Tod S. Heiles - Vancouver WA
Dan Arquilevich - Portland OR

Assignee:

Hewlett-Packard Development Company, L.P. - Houston TX

International Classification:

B41J 29393

US Classification:

347 3, 347 19

Abstract:

A compact optical sensing system is used in hardcopy devices for scanning and/or printing images, for instance, using inkjet printing technology in desktop printing or in photographic printers appearing in grocery and variety stores. Several light emitting diodes (âLEDsâ) illuminate a sheet of print media, and one or more photodiodes receive light reflected from the sheet. The photodiode generates signals in response to the light received, and the hardcopy device uses these signals to adjust printing parameters for optimal print quality. Using a chip-on-board process, the bare silicon die for each component is wire bonded directly to a printed circuit board assembly, allowing at least four LEDs (blue, green, red and soft-orange) to be grouped closely together in a space smaller than that occupied by a factory-made, single-packaged LED. A calibrating system uses a white target covered for cleanliness by a windowed door which is opened/closed by a printhead carriage.