Patents by Inventor Brett E. Dahlgren

Brett E. Dahlgren has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8390810
    Abstract: A color sensing apparatus (10) includes an optical system (16) that produces a spatially uniform light beam (18).
    Type: Grant
    Filed: December 20, 2007
    Date of Patent: March 5, 2013
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Stephan R. Clark, Brett E. Dahlgren
  • Patent number: 8355127
    Abstract: One aspect is a light source assembly in a drop detection arrangement. The light source assembly includes a light source and a gradient-index lens array to at least partially collimate light from the light source and to project a collimated light beam into the drop detection arrangement in a direction transverse to a drop direction of droplets in the drop detection arrangement. The light source assembly produces the light beam such that it has a beam width in a direction transverse to the drop direction that is larger than a beam height in the drop direction.
    Type: Grant
    Filed: July 15, 2010
    Date of Patent: January 15, 2013
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Alexander Govyadinov, Brett E. Dahlgren, Lenward Seals
  • Patent number: 8319969
    Abstract: A color detector includes a light source, a first filter, and a first photodetector. The light source generates light within a spectrum of wavelengths. The first filter is in optical communication with the light source and is configured to pass light within a first predetermined spectrum of wavelengths. The first photodetector is in optical communication with the first filter and is configured to output a first color signal if light passes through the first filter. The photodetector has an area configured to equalize the first color signal and maximize a signal-to-noise ratio of the first color signal.
    Type: Grant
    Filed: February 13, 2008
    Date of Patent: November 27, 2012
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Stephan R. Clark, Andrew L. VanBrocklin, Brett E. Dahlgren
  • Patent number: 8125625
    Abstract: Hard copy re-emission color measurement system, comprising a light arrangement for emitting light onto a hard copy, a light detector arranged to detect light re-emitted by the hard copy, and a control circuit configured to process the detected re-emitted light. The light arrangement is arranged to separately and simultaneously emit a first light having wavelengths longer than an ultraviolet wavelength and a second light having wavelengths in the ultraviolet range. The light arrangement is provided with a light guide arranged to guide the first and second light on an at least partly overlapping region on a hard copy.
    Type: Grant
    Filed: July 12, 2009
    Date of Patent: February 28, 2012
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Stephan Clark, Brett E Dahlgren
  • Publication number: 20120038923
    Abstract: An optical system includes a lens, a pupil relay, and an aperture stop positioned at a focal point of the lens between the lens and the pupil relay. The lens is configured to collect a plurality of light bundles. Each light bundle emanates from a field point of an object plane and has a center ray substantially parallel to an optical axis of the lens. The lens is configured to direct the center ray of each light bundle through the aperture stop and onto the pupil relay. The pupil relay is configured to image a plane of the aperture stop onto a sensor array.
    Type: Application
    Filed: April 20, 2009
    Publication date: February 16, 2012
    Inventors: Stephan Clark, Brett E. Dahlgren
  • Publication number: 20120013906
    Abstract: One aspect is a light source assembly in a drop detection arrangement. The light source assembly includes a light source and a gradient-index lens array to at least partially collimate light from the light source and to project a collimated light beam into the drop detection arrangement in a direction transverse to a drop direction of droplets in the drop detection arrangement. The light source assembly produces the light beam such that it has a beam width in a direction transverse to the drop direction that is larger than a beam height in the drop direction.
    Type: Application
    Filed: July 15, 2010
    Publication date: January 19, 2012
    Inventors: Alexander Govyadinov, Brett E. Dahlgren, Lenward Seals
  • Publication number: 20110310389
    Abstract: A color sensor array includes a plurality of sensors. Each of the plurality of sensors has a width dimension and a length dimension that is elongated with respect to the width dimension. The length dimensions of the sensors are substantially equal to one another and parallel to an illumination plane. Each of the plurality of sensors includes a face defined by opposing first and second elongated sides and opposing first and second non-elongated sides. The first non-elongated sides of the plurality of sensors are aligned with one another along an axis that is substantially perpendicular to the illumination plane.
    Type: Application
    Filed: February 27, 2009
    Publication date: December 22, 2011
    Inventors: Stephan R. Clark, Brett E. Dahlgren
  • Publication number: 20110211196
    Abstract: A color measurement device includes a light pipe and a light source. The light pipe is oriented length-wise towards a color sample surface along a first axis that is non-perpendicular to the surface. A color sample is positioned on the surface. The light pipe has a near opening, a far opening, and a face at the far opening. The near opening is closer to the color sample than the far opening. The light source is positioned near the far opening of the light pipe, and is to output light along a second axis and into the light pipe at the far opening. The light reflects off the surface after exiting the light pipe at the near opening. The second axis is non-perpendicular to the face of the light pipe at the far opening. The light non-uniformly illuminates the color sample after exiting the light pipe at the near opening.
    Type: Application
    Filed: October 31, 2008
    Publication date: September 1, 2011
    Inventors: Brett E. Dahlgren, Stephan R. Clark
  • Publication number: 20110096343
    Abstract: A method includes collecting, within a printer body, ambient light entering the printer body. Characteristics of the collected ambient light are measured. A color profile based on the measured characteristics is identified. The identified color profile is provided for use in forming a color image on a medium.
    Type: Application
    Filed: October 23, 2009
    Publication date: April 28, 2011
    Inventors: Oscar Martinez, Brett E. Dahlgren
  • Patent number: 7916301
    Abstract: A color detector includes a light source configured to generate light with a spectrum of wavelengths; a plurality of filters in optical communication with the light source, wherein each filter is configured to pass a bandwidth of wavelengths around a different peak wavelength; and a plurality of photodetectors, each configured to receive light passed through a respective filter of the plurality of filters. The bandwidth of each filter is configured to Correspond to a bandwidth of a curve from a set of standard color matching functions. A method for improving color detection accuracy in a color detector includes matching a bandwidth passed by each of a plurality of color filters with a bandwidth and peak wavelength of a Commission Internationale de l'Eclairage (CIE) color matching function; and separately detecting an amount of light passed by each the filter.
    Type: Grant
    Filed: October 14, 2008
    Date of Patent: March 29, 2011
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventor: Brett E. Dahlgren
  • Patent number: 7894064
    Abstract: An optical device includes an aperture stop that limits an angular extent of light from an illuminated sample. A first lens is positioned between the aperture stop and a detector plane. A second lens is positioned between the first lens and the detector plane and is operable to map light from the aperture stop to the detector plane such that the light is averaged at the detector plane.
    Type: Grant
    Filed: January 10, 2008
    Date of Patent: February 22, 2011
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Stephan R. Clark, Brett E. Dahlgren
  • Publication number: 20110007302
    Abstract: Hard copy re-emission color measurement system, comprising a light arrangement for emitting light onto a hard copy, a light detector arranged to detect light re-emitted by the hard copy, and a control circuit configured to process the detected re-emitted light. The light arrangement is arranged to separately and simultaneously emit a first light having wavelengths longer than an ultraviolet wavelength and a second light having wavelengths in the ultraviolet range. The light arrangement is provided with a light guide arranged to guide the first and second light on an at least partly overlapping region on a hard copy.
    Type: Application
    Filed: July 12, 2009
    Publication date: January 13, 2011
    Inventors: Stephan Clark, Brett E. Dahlgren
  • Publication number: 20100321694
    Abstract: A color detector includes a light source, a filter, and a photodetector. The photodetector outputs a signal proportional to the amount of a predetermined color of light that passes through the corresponding filter. When used in an array, each filter may have different transmission characteristics, and each color signal may have a different magnitude and/or signal-to-noise ratio. This may be corrected for by adjusting the area of each of the photodetectors and corresponding filters. In other words, the areas if the photodetectors may be configured to equalize the color signal of a reference color and thereby maximize the signal-to-noise ratio of the color signals the sensor is intended to measure. The area of the photodetector may be based on a response curve of the photodetector as a function of wavelength, a response curve of the filter as a function of wavelength, and the amount of light as a function of wavelength generated by the light source, among other factors.
    Type: Application
    Filed: February 13, 2008
    Publication date: December 23, 2010
    Inventors: Stephan R. Clark, Andrew L. Vanbrocklin, Brett E. Dahlgren
  • Patent number: 7768538
    Abstract: One embodiment provides a method that includes displaying Boolean combinations of two or more bit planes.
    Type: Grant
    Filed: May 9, 2005
    Date of Patent: August 3, 2010
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Wiatt E. Kettle, Brett E. Dahlgren, Matthew J. Gelhaus
  • Publication number: 20100091286
    Abstract: A color detector includes a light source configured to generate light with a spectrum of wavelengths; a plurality of filters in optical communication with the light source, wherein each filter is configured to pass a bandwidth of wavelengths around a different peak wavelength; and a plurality of photodetectors, each configured to receive light passed through a respective filter of the plurality of filters. The bandwidth of each filter is configured to Correspond to a bandwidth of a curve from a set of standard color matching functions. A method for improving color detection accuracy in a color detector includes matching a bandwidth passed by each of a plurality of color filters with a bandwidth and peak wavelength of a Commission Internationale de I'Eclairage (CIE) color matching function; and separately detecting an amount of light passed by each the filter.
    Type: Application
    Filed: October 14, 2008
    Publication date: April 15, 2010
    Inventor: Brett E. Dahlgren
  • Publication number: 20090180117
    Abstract: An optical device includes an aperture stop that limits an angular extent of light from an illuminated sample. A first lens is positioned between the aperture stop and a detector plane. A second lens is positioned between the first lens and the detector plane and is operable to map light from the aperture stop to the detector plane such that the light is averaged at the detector plane.
    Type: Application
    Filed: January 10, 2008
    Publication date: July 16, 2009
    Inventors: Stephan R. Clark, Brett E. Dahlgren
  • Patent number: 7441909
    Abstract: An optical assembly for a projection system includes an objective lens and a retro-focus lens. Then objective lens and retro-focus lens share one or more lens elements. A method of projecting an image comprises directing light from a light source to one or more modulators and projecting a modulated light beam using an optical assembly that includes an objective lens and a retro-focus lens that share one or more lens elements.
    Type: Grant
    Filed: January 20, 2005
    Date of Patent: October 28, 2008
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Scott Lerner, James W. Ring, Brett E. Dahlgren
  • Patent number: 6972882
    Abstract: A micro-mirror device includes a substrate and a plate spaced from and oriented substantially parallel to the substrate such that the plate and the substrate define a cavity therebetween. A reflective element is interposed between the substrate and the plate, and a liquid having an index of refraction greater than one is disposed in the cavity between at least the reflective element and the plate. As such, the reflective element is adapted to move between a first position and at least one second position.
    Type: Grant
    Filed: March 12, 2003
    Date of Patent: December 6, 2005
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: James W. Ring, Brett E. Dahlgren, Terry E. McMahon