Patents by Inventor Michael L Christensen

Michael L Christensen 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: 6614563
    Abstract: A transparency adaptor is described that includes a flat panel illuminator within the scanner lid of the scanner. The flat panel illuminator provides backlighting for scanning transparencies, such that light passes through the transparency only once and into the scanner optics within the scanner base. When the flat panel illuminator is lit during a scanning process, the light source within the scanner is not lit. In a second embodiment, the flat panel illuminator is removeably attached to the scanner lid. Another alternative is for the flat panel illuminator adapter to be a separate from the scanner, such that it is placed over a transparent document when needed, either plugging into the scanner or a separate power source during the scanning process.
    Type: Grant
    Filed: March 30, 1999
    Date of Patent: September 2, 2003
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Patrick A Batten, Michael L Christensen, John G Thelen
  • Patent number: 6316767
    Abstract: An apparatus for connecting electrical power to an exposure lamp in an image scanner in response to the detection of ambient light by a light sensor located under the scanner's cover. Such an apparatus provides an apparent reduction in exposure lamp warm-up time, with associated improvement in operator productivity, while minimizing exposure lamp operational life degradation and excessive energy consumption caused by leaving the exposure lamp turned on. Once the exposure lamp is turned on, a timing circuit is used in the preferred embodiment to disconnect electrical power from the exposure lamp so that if the scanner's cover is left open or closed, the exposure lamp will not be left on for excessively long periods of time.
    Type: Grant
    Filed: September 17, 1999
    Date of Patent: November 13, 2001
    Assignee: Hewlett-Packard Company
    Inventors: Dan C Paxton, Michael L Christensen, Eugene W Pakenham
  • Patent number: 6166829
    Abstract: An optical image scanner includes a scan head that is mounted onto a guide member with a bias torque that reduces uncertainty in position of the scan head. A drive member, such as a belt or cable, is attached to the scan head with an offset relative to a centerline of the guide member. A tensioning device ensures that the drive member asserts force on the scan head at each of the attachment points. As a result, a bias torque is placed onto the scan head, relative to the guide member, reducing uncertainty in position. For bidirectional movement, the biasing torque is the same for either direction of travel.
    Type: Grant
    Filed: April 28, 1998
    Date of Patent: December 26, 2000
    Assignee: Hewlett-Packard Company
    Inventors: Michael L. Christensen, Stephen J. Cook
  • Patent number: 6147343
    Abstract: Disclosed herein is a method and apparatus for compensating for temperature-induced scan line drift in a photoelectric imaging apparatus. A scan line drift compensation mechanism may be placed in contact with at least one of the optical components, e.g, a mirror, contained within the optical system of a photoelectric imaging apparatus. The scan line drift compensation mechanism may be formed from two members, each having a different coefficient of thermal expansion. In this manner, the scan line drift compensation mechanism is able to exert a force on the optical component in response to a change in temperature.
    Type: Grant
    Filed: July 23, 1998
    Date of Patent: November 14, 2000
    Assignee: Hewlett-Packard Company
    Inventor: Michael L. Christensen
  • Patent number: 6018161
    Abstract: An adapter for scanning transparent images using a reflective scanner. The adapter receives light from a lamp inside the scanner and redirects the light through the transparent image and back into the scanner. The scanner has an offset between an illumination line and a scan line. An angle of the adapter relative to the surface of a platen on the scanner is dependent on the distance between the illumination line and the scan line. At least one angle adjuster is provided on the adapter to enable the adapter to be used on scanners having different offsets. In addition, the adapter is made wider than the transparent image to be scanned, so that when the scan line is at a leading or trailing edge of the transparent image, the adapter still captures light from the lamp within the scanner.
    Type: Grant
    Filed: July 31, 1998
    Date of Patent: January 25, 2000
    Assignee: Hewlett-Packard Company
    Inventors: Patrick A. Batten, Michael L. Christensen, Martha A. Chavez
  • Patent number: 5895913
    Abstract: Apparatus for sensing an initial position of a moveable carriage mounted within a housing of an imaging device may comprise a detector having a plurality of light sensitive elements for detecting objects within a field of view. At least one of the light sensitive elements is an image sensing element and at least one of the light sensitive elements is a position sensing element. A reference mark is positioned on the housing so that is within the field of view of the position sensing element of the detector when the carriage is at about a home position. An image data processor connected to the detector and responsive to the output signals generated thereby determines whether the reference mark is within the field of view of the position sensing element of the detector.
    Type: Grant
    Filed: January 9, 1997
    Date of Patent: April 20, 1999
    Assignee: Hewlett-Packard Company
    Inventor: Michael L. Christensen
  • Patent number: 5753908
    Abstract: An apparatus and method for achieving alignment of a photosensor array in an imaging device is disclosed. The photosensor array is mounted in an integrated circuit package having a plurality of downwardly extending leads. The leads are received in a plurality of sockets which are attached to and extend through the retina board. A pair of holes are provided extending through the retina board proximate the ends of the integrated circuit package. An actuator, such as a screw, is associated with each hole such that the actuator is able to contact the rear surface of the integrated circuit package. In this manner, one of the actuators may be used to apply a force to one end of the integrated circuit package in order to move that end away from the retina board and thus achieve alignment with the light beam.
    Type: Grant
    Filed: January 9, 1997
    Date of Patent: May 19, 1998
    Assignee: Hewlett-Packard Company
    Inventor: Michael L. Christensen
  • Patent number: 4857009
    Abstract: A fixture latching mechanism for mass terminating a printed circuit test fixture to a test head probe field wherein said fixture latching mechanism is comprised of simultaneously functioning pulldown towers, each of which further comprises a housing having an internal wall for guiding a vertically moving rack containing a horizontally and forwardly biased pulldown which engages the fixture as the rack is powered downward and which disengages from the fixture as the rack is powered upward. Preferably, the disengagement of the pulldown from the fixture is produced by a caming action on a cam follower attached to the rear portion of the pulldown as the cam follower engages a cam system positioned in the upper regions of the housing's internal wall.
    Type: Grant
    Filed: July 21, 1988
    Date of Patent: August 15, 1989
    Assignee: Hewlett-Packard Company
    Inventor: Michael L. Christensen
  • Patent number: D338416
    Type: Grant
    Filed: July 25, 1988
    Date of Patent: August 17, 1993
    Assignee: Hewlett-Packard Company
    Inventors: James E. Berry, Brent W. Thordarson, Michael L. Christensen