Patents Examined by Peter Kovacs
  • Patent number: 5712691
    Abstract: A method and projection television system for projecting images having a plurality of color components, includes a device for filtering a first color component signal from a composite signal to provide a filtered first color component signal. A defocusing mechanism defocuses the first color component signal based on the filtered first color component signal. A gain adjustment device adjusts a gain of at least one other of a plurality of color component signals of the composite signal. An amount of defocusing performed by the defocusing mechanism and a gain adjustment by the gain adjustment device are dependent on a content of the composite signal. In another aspect of the invention, a spot wobble scheme may be employed alone in a static defocussing system, without dependence upon the video signal content.
    Type: Grant
    Filed: December 5, 1995
    Date of Patent: January 27, 1998
    Assignee: Philips Electronics North America Corporation
    Inventor: Matthew Scott Brennesholtz
  • Patent number: 5673063
    Abstract: A video display driver applies a video signal to pixels arranged in columns and rows of a liquid crystal display. A given column or data line driver includes a field effect transistor that operates as a comparator. The comparator is responsive to the video signal and to a reference ramp signal. A triggering voltage of the comparator is automatically and periodically adjusted. A drain voltage of the transistor that is equal to a threshold voltage of the transistor is developed in a stray capacitance, during the automatic adjustment period. A pulse signal, is coupled via the capacitance to increase the drain voltage. The drain voltage is applied to a gate electrode of a second field effect transistor that applies a data ramp voltage to the pixels. The pulse signal provides a small amount of drive in the second transistor.
    Type: Grant
    Filed: March 6, 1995
    Date of Patent: September 30, 1997
    Assignee: Thomson Consumer Electronics, S.A.
    Inventor: Sherman Weisbrod
  • Patent number: 5671023
    Abstract: A gamma correction circuit capable of faithfully monitoring and outputting the color and luminance of an object without deteriorating the resolution.
    Type: Grant
    Filed: November 6, 1995
    Date of Patent: September 23, 1997
    Assignee: Sony Corporation
    Inventors: Kazuhiko Nishiwaki, Ken Nakajima
  • Patent number: 5657099
    Abstract: A SLM-based projection display system (10) samples and processes video data for delivery to a spatial light modulator (SLM) (13c), and uses a color wheel (14a) to color the SLM-generated images. A frame memory (13b) provides data to the SLM (13c) and is managed so that, if the phase of the incoming video signal changes, a desired phase relationship between the color wheel position and the data available to the SLM (13c) can be maintained. Also, a motor control unit (15a) uses a horizontal sync signal to generate a drive signal for the color wheel motor (16a), which limits the transient time during phase-changing events, and which provides a means for adjusting the phase of the drive signal.
    Type: Grant
    Filed: August 1, 1995
    Date of Patent: August 12, 1997
    Assignee: Texas Instruments Incorporated
    Inventors: Donald B. Doherty, Richard C. Meyer, Stephen W. Marshall, Jefferey B. Sampsell, Robert J. Gove
  • Patent number: 5610663
    Abstract: The present invention relates to a multi-frequency displaying device for displaying both TV and PC video signals. The displaying device comprises a displaying screen for displaying TV or PC video signals, a video signal processing circuit for converting the TV video signals into TV RGB signals and TV sync signals, a sync circuit for converting the TV sync signals or PC sync signals into vertical and horizontal deflection signals, and a display control circuit for displaying the TV RGB signals or PC RGB signals in the display screen in synchronization with the vertical and horizontal deflection signals. The sync circuit comprises a multi-frequency horizontal oscillator for generating clock signals to convert the TV sync signals or PC sync signals with different frequencies into the horizontal deflection signals according to the switch.
    Type: Grant
    Filed: January 17, 1996
    Date of Patent: March 11, 1997
    Assignee: Acer Peripherals, Inc.
    Inventors: Liu P. Nan, Leu J. Hwei