Patents by Inventor Roger N. Marshall

Roger N. Marshall 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: 5933132
    Abstract: A method and apparatus geometrically makes correction in an optical computer input system.
    Type: Grant
    Filed: May 15, 1996
    Date of Patent: August 3, 1999
    Assignee: Proxima Corporation
    Inventors: Roger N. Marshall, Lane T. Hauck
  • Patent number: 5594468
    Abstract: A method and optical system auxiliary input calibration arrangement accurately and reliably discriminate between a user generated image and a video source generated image, such as one produced by a computer. The calibration arrangement includes amplifier devices for increasing the strength of a video information signal indicative of the video generated image, and a user generated auxiliary input signal indicative of an auxiliary input light image, without increasing spurious ambient light signals. A discrimination circuit generates a detection signal whenever the amplified information signals are greater than a predetermined reference level signal. A microprocessor calculates the appropriate predetermined reference level signal based upon ambient lighting conditions, the strength of that portion of the information signal indicative of the video image, the type of optical system and the distance the optical system is disposed away from a viewing surface.
    Type: Grant
    Filed: November 21, 1994
    Date of Patent: January 14, 1997
    Assignee: Proxima Corporation
    Inventors: Roger N. Marshall, Richard M. Lizon, Jeffrey W. Busch, Lane T. Hauck
  • Patent number: 5543819
    Abstract: A method and system for producing a finely textured display image of a gradation of high color resolution color shading. The high color resolution system is adapted to be coupled to a relatively inexpensive high speed active matrix display panel employing single-bit LCD drivers and a plurality of sub-pixel elements. The system includes a sub-pixel activation circuit for generating single-bit digital signals for driving individual ones of the sub-pixel elements. A duty cycle circuit arrangement controls the sub-pixel activation circuit to cause desired ones of the sub-pixel elements to be activated selectively an average number of times over a large number of consecutive frame time intervals to generate sub-pixel images having desired perceived color shading levels.
    Type: Grant
    Filed: November 19, 1993
    Date of Patent: August 6, 1996
    Assignee: Proxima Corporation
    Inventors: Randall S. Farwell, Robert W. Shaw, Roger N. Marshall
  • Patent number: 5502459
    Abstract: The optical auxiliary input arrangement for an optical system projecting computer generated images includes an image processing unit and communication interface for detecting the speed at which two high intensity auxiliary light images flash onto the projected computer image, to interpret the images as a mouse double click feature. The optical auxiliary input arrangement accurately and reliably discriminates between user generated double click information without the need of the user being so steady of hand as to cause the auxiliary light information beam to illuminate the same precise location on the viewing surface during the double click operation. The image processing unit and communication interface cooperate together to permit both a low speed mouse and the high speed light generating device to communicate with the system.
    Type: Grant
    Filed: April 19, 1994
    Date of Patent: March 26, 1996
    Assignee: Proxima Corporation
    Inventors: Roger N. Marshall, Richard M. Lizon, Lane T. Hauck
  • Patent number: 5489923
    Abstract: A method and apparatus facilitates the alignment and light sensitivity adjustment of an optical computer input system, which includes a user generated light directed onto a screen bearing a computer generated image, to convey information to the computer interactively by the user, even in a darkened room. The system discriminates between the user generated image, and the computer generated image. Devices facilitate the proper alignment of the system with the screen, as well as proper light sensitivity adjustments.
    Type: Grant
    Filed: November 19, 1993
    Date of Patent: February 6, 1996
    Assignee: Proxima Corporation
    Inventors: Roger N. Marshall, Lane T. Hauck, Leonid Shapiro, Jeffrey W. Busch, Eric S. Stevens
  • Patent number: 5181015
    Abstract: A method and apparatus facilitates the alignment and light sensitivity adjustment of an optical computer input system, which includes a user generated light directed onto a screen bearing a computer generated image, to convey information to the computer interactively by the user, even in a darkened room. The system discriminates between the user generated image, and the computer generated image. Devices facilitate the proper alignment of the system with the screen, as well as proper light sensitivity adjustments.
    Type: Grant
    Filed: November 9, 1990
    Date of Patent: January 19, 1993
    Assignee: Proxima Corporation
    Inventors: Roger N. Marshall, Lane T. Hauck, Leonid Shapiro, Jeffrey W. Busch, Eric S. Stevens