David K Towner

US Patent:

6536907, Mar 25, 2003

Filed:

Feb 8, 2000

Appl. No.:

09/499707

Inventors:

David K. Towner - Boise ID
Mark Butterworth - Santa Clara CA

Assignee:

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

International Classification:

G03B 2100

US Classification:

353121, 353 69, 353 70, 348745, 348746, 348747, 348771, 396115, 396149, 396150

Abstract:

Optical projection systems for the display of electronic images often suffer from degraded image quality due to color field registration errors caused by lateral chromatic aberration. Although most projection lenses are partially corrected for lateral chromatic aberration during the design process, the uncorrected residual aberration limits the imaging performance of many projection displays, especially when displaying text and graphics with single-pixel-wide features. Some embodiments of the invention correct color field registration errors due to lateral chromatic aberration in multiple-imager projection systems. Other embodiments of the invention correct radial distortion and keystone distortion in single-imager and multiple-imager projection displays. In some embodiments of the invention, the imager(s) pixel geometry is arranged to compensate for optical aberrations, which result from the optical system so as to achieve a corrected image.

US Patent:

6559878, May 6, 2003

Filed:

Dec 20, 2000

Appl. No.:

09/747049

Inventors:

George V. McIlvaine - Boise ID
Laurent A. Regimbal - Eagle ID
David K. Towner - Boise ID

Assignee:

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

International Classification:

B41J 2435

US Classification:

347228, 347156

Abstract:

An apparatus and method are provided for fusing toner to a print medium. According to one embodiment, the apparatus includes a laser source optically coupled to a predefined position in a print medium pathway. A laser beam generated by the laser source is directed to fall upon the print medium shuttled along the print medium pathway. Finally, a laser controller is coupled to the laser source to control the laser beam to generate a predefined fusing exposure of the laser beam on the print medium.

US Patent:

6765739, Jul 20, 2004

Filed:

Mar 18, 2002

Appl. No.:

10/100454

Inventors:

Josh N. Hogan - Los Altos CA
David K. Towner - Boise ID

Assignee:

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

International Classification:

G11B 1904

US Classification:

360 60, 386 94, 380203, 369 5321

Abstract:

A method and apparatus for creating a machine-readable medium such as a CD or a DVD disc is disclosed. The disc includes encoded copy protection data that, when decoded and re-encoded, produces a tracking prevention sequence of bits that causes a duplicate disc (containing the re-encoded copy protection data) to temporarily lose tracking. The temporary loss of tracking is utilized to render the duplicated disc unusable by placing key data immediately following the encoded copy protection data.

US Patent:

7271822, Sep 18, 2007

Filed:

Oct 28, 2004

Appl. No.:

10/978014

Inventors:

David Kenney Towner - Boise ID, US

Assignee:

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

International Classification:

B41J 2/435

US Classification:

347234, 347248

Abstract:

Systems and methods are described for stitching multiple images together in a printer to form a single, seamless, composite image. The use of multiple laser sources and multiple scan lenses with one or more scanner assemblies and various image stitching methods achieves seamless image stitching in a manner that provides benefits over prior printers using single laser sources and single scan lenses. Such benefits include, for example, a wider image format, smaller optical spot size, reduced cost, and reduced overall size for the printer.

US Patent:

7460146, Dec 2, 2008

Filed:

Oct 28, 2004

Appl. No.:

10/978078

Inventors:

David K. Towner - Boise ID, US

International Classification:

B41J 27/00
B41J 2/47
B41J 2/435

US Classification:

347259, 347234, 347248

Abstract:

Systems and methods are described that dynamically correct field curvature and other focus errors in imaging systems that use rotating scanners to scan an image field. The dynamic correction controls the focusing of an image field such that focus is maintained across the width of a photosensitive element as a rotating scanner scans the field. The described systems and methods enable the use of post-objective scanning configurations in which the complexity and expense of objective lenses is significantly reduced.

US Patent:

7701836, Apr 20, 2010

Filed:

Aug 9, 2006

Appl. No.:

11/416589

Inventors:

Daniel Y. Abramovitch - Palo Alto CA, US
David K. Towner - Boise ID, US

Assignee:

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

International Classification:

G11B 7/24

US Classification:

3692754

Abstract:

An optical disk structure and optical disk recorder which enables data to be re-written onto the recording layer of the optical disk. A clock reference structure is permanently formed along servo tracks of the optical disk. An optical transducer is coupled to the clock reference structure and generates a clock reference signal simultaneously with writing new data onto the recording layer of the optical disk. The data is written as data marks along the servo tracks. Each of the data marks includes edges. The edges of the data marks are recorded in synchronization with a write clock. The write clock is phase-locked with the clock reference signal. Therefore, the edges of the data marks are aligned with the clock reference structure with sub-bit accuracy. Standard DVD-ROM disk readers are not able to detect the high spatial frequency of the clock reference structure. Therefore, the optical disk structure and optical disk recorder of this invention allow production of re-writable optical disks which can be read by standard DVD-ROM disk readers.

US Patent:

7751124, Jul 6, 2010

Filed:

Oct 27, 2008

Appl. No.:

12/258739

Inventors:

David Kenney Towner - Boise ID, US
Michael Plotkin - Rehovot, IL

Assignee:

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

International Classification:

G02B 13/10
G02B 5/04

US Classification:

359669, 359831

Abstract:

Various embodiments and methods relating to groups of anamorphic prisms that are configured to reduce smile in a multi-beam optical system are disclosed.

US Patent:

RE41881, Oct 26, 2010

Filed:

Nov 27, 2001

Appl. No.:

09/997036

Inventors:

Daniel Y. Abramovitch - Palo Alto CA, US
David K. Towner - Boise ID, US

Assignee:

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

International Classification:

G11B 27/24

US Classification:

369 4728, 3692754, 369 592

Abstract:

An optical disk structure and optical disk recorder which enables data to be rewritten onto the recording layer of the optical disk. A clock reference structure is permanently formed along servo tracks of the optical disk. An optical transducer is coupled to the clock reference structure and generates a clock reference signal simultaneously with writing new data onto the recording layer of the optical disk. The data is written as data marks along the servo tracks. Each of the data marks includes edges. The edges of the data marks are recorded in synchronization with a write clock. The write clock is phase-locked with the clock reference signal. Therefore, the edges of the data marks are aligned with the clock reference structure with sub-bit accuracy. Standard DVD-ROM disk readers are not able to detect the high spatial frequency of the clock reference structure. Therefore, the optical disk structure and optical disk recorder of this invention allow production of re-writable optical disks which can be read by standard DVD-ROM disk readers.