Color Television Patents (Class 348/727)
  • Patent number: 5473388
    Abstract: A signal demodulator apparatus comprises: an input terminal (11) for inputting an external signal; a delay line (12) connected to the input terminal, for outputting a first delay signal obtained by delaying the external signal by a predetermined time; a phase corrector (13) responsive to the first delay signal outputted by the delay line, for correcting phase of the first delay signal on the basis of a phase difference detection signal and outputting the first phase-corrected delay signal as a second delay signal; and a phase difference detector (16, 15, 19, 20) for detecting a phase difference between the second delay signal outputted by said phase corrector and the external signal inputted through the input terminal and for outputting the phase difference detection signal to the phase corrector to correct the phase difference to a predetermined value.
    Type: Grant
    Filed: February 23, 1994
    Date of Patent: December 5, 1995
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kazuki Takaki, Yoshio Wada
  • Patent number: 5457500
    Abstract: In a television system including a source of an intermediate frequency (IF) signal, which signal includes an IF picture carrier amplitude modulated with video information, synchronous demodulator means responds to the IF signal, for providing an in-phase first output video signal that has both luminance and chrominance components, and for providing a quadrature-phase second output video signal that has a chrominance component but substantially no luminance component. Chroma circuitry is responsive to the quadrature-phase second output video signal for generating first and second color-difference signals.
    Type: Grant
    Filed: November 4, 1994
    Date of Patent: October 10, 1995
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jack R. Harford
  • Patent number: 5418575
    Abstract: A color display apparatus for a video information system includes an input for receiving at least one externally applied color component signal, a display device having predetermined color characteristics, and a compensating unit responsive to the at least one externally applied color component signal from the input for compensating at least a portion of the at least one externally applied color component signal in accordance with the predetermined color characteristics of the display device. The display device is responsive to the input and the compensating unit for displaying a color image of the externally applied color component signal.
    Type: Grant
    Filed: February 25, 1994
    Date of Patent: May 23, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Atsushi Kaneko, Hideaki Ohki, Akio Nakashima, Junichi Ikoma
  • Patent number: 5359368
    Abstract: A line locked digital color demodulator separates the V and U color components and the burst signal and uses a ROM for providing phase shifts to the V and U demodulation axes. During the burst time of an NTSC signal, the color component axes are shifted by 45.degree. such that the burst signal produces equal components along the axes. A correction signal is developed in response to this shifting and is used in conjunction with a frequency error signal for continuously addressing the ROM. The error signal is developed by counting the number of clock pulses over a 16 line period and comparing the number counted with a standard number for the type signal being received. The error signal is combined with the correction signal for adjusting the phase of the V and U demodulation axes. For a PAL signal, the burst is normalized to always be at 135.degree. and its components along the V and -U axes are compared as with the NTSC signal.
    Type: Grant
    Filed: April 12, 1993
    Date of Patent: October 25, 1994
    Assignee: Zenith Electronics Corporation
    Inventor: Gopal K. Srivastava