Patents by Inventor Hajime Sumiyoshi
Hajime Sumiyoshi 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: 6529247Abstract: A detector circuit detects a voltage corresponding to the leakage current that flows through the cathode electrode of a color display during a vertical blanking period of a video signal. The voltage detected is held in a first sample-and-hold circuit. Meanwhile, a reference signal corresponding to the reference black level is input during a part of the vertical blanking period of the video signal. A voltage corresponding to the leakage current that flows through the cathode electrode of the color display during the part of the vertical blanking period is detected by the detector circuit and then held in a second sample-and-hold circuit. The voltage held in the first sample-and-hold is subtracted from the voltage held in the second sample-and-hold circuit. A comparator circuit compares the difference between these voltages with a reference voltage. The result of the comparison controls a cutoff adjustment circuit for adjusting a DC level of the video signal.Type: GrantFiled: June 4, 2002Date of Patent: March 4, 2003Assignee: Kabushiki Kaisha ToshibaInventors: Reiji Tagomori, Kenji Hara, Hajime Sumiyoshi
-
Publication number: 20020149701Abstract: A detector circuit detects a voltage corresponding to the leakage current that flows through the cathode electrode of a color display during a vertical blanking period of a video signal. The voltage detected is held in a first sample-and-hold circuit. Meanwhile, a reference signal corresponding to the reference black level is input during a part of the vertical blanking period of the video signal. A voltage corresponding to the leakage current that flows through the cathode electrode of the color display during the part of the vertical blanking period is detected by the detector circuit and then held in a second sample-and-hold circuit. The voltage held in the first sample-and-hold is subtracted from the voltage held in the second sample-and-hold circuit. A comparator circuit compares the difference between these voltages with a reference voltage. The result of the comparison controls a cutoff adjustment circuit for adjusting a DC level of the video signal.Type: ApplicationFiled: June 4, 2002Publication date: October 17, 2002Inventors: Reiji Tagomori, Kenji Hara, Hajime Sumiyoshi
-
Patent number: 6437833Abstract: A detector circuit detects a voltage corresponding to the leakage current that flows through the cathode electrode of a color display during a vertical blanking period of a video signal. The voltage detected is held in a first sample-and-hold circuit. Meanwhile, a reference signal corresponding to the reference black level is input during a part of the vertical blanking period of the video signal. A voltage corresponding to the leakage current that flows through the cathode electrode of the color display during the part of the vertical blanking period is detected by the detector circuit and then held in a second sample-and-hold circuit. The voltage held in the first sample-and-hold is subtracted from the voltage held in the second sample-and-hold circuit. A comparator circuit compares the difference between these voltages with a reference voltage. The result of the comparison controls a cutoff adjustment circuit for adjusting a DC level of the video signal.Type: GrantFiled: November 17, 1999Date of Patent: August 20, 2002Assignee: Kabushiki Kaisha ToshibaInventors: Reiji Tagomori, Kenji Hara, Hajime Sumiyoshi
-
Patent number: 6201426Abstract: A pulse generating device generates an output pulse by controlling the amplitude of a triangular wave at a constant level by use of an AGC circuit and wave-shaping the triangular wave when the triangular wave is generated by triggering a monostable multivibrator circuit by an input pulse, driving an integrating circuit having substantially the constant charging/discharging ratio by an output of the monostable multivibrator circuit, and controlling a current source which supplies a current to the integrating circuit according to an output of comparison between the integrated output and a reference voltage.Type: GrantFiled: September 10, 1999Date of Patent: March 13, 2001Assignee: Kabushiki Kaisha ToshibaInventors: Hajime Sumiyoshi, Takeshi Namikawa
-
Patent number: 5760839Abstract: A horizontal synchronizing apparatus includes a source for providing a horizontal synch. signal, a horizontal deflection circuit for generating a deflection current having scanning intervals and blanking intervals repetitively successing in response to driving pulses and having retrace pulses which delay from the driving pulses as a function of a load on the horizontal deflection circuit, a phase locked loop having an input, an output and a first feedback path, for producing from the output a substantial bi-level signal synchronized to the horizontal synch. signal applied to the input, and a phase controlled loop having an input, an output and a second feedback path, for maintaining the retrace pulses synchronous with the bi-level signals.Type: GrantFiled: March 6, 1996Date of Patent: June 2, 1998Assignee: Kabushiki Kaisha ToshibaInventor: Hajime Sumiyoshi
-
Patent number: 5596374Abstract: A television receiver includes a first signal processing unit that generates contrast controlled first R, G and B signals and a second signal processing unit that outputs second on-screen R, G and B signals. A switching unit receives the first and second R, G and B signals and selectively outputs one of them to a color CRT. An ABL voltage, which changes in response to a level of video displayed on the CRT, is provided to the first and the second R, G and B signals. A control unit determines whether to execute the contrast control of the second R, G and B signals based on a ratio of video corresponding to the second R, G and B signals out of the total video displayed on the color CRT.Type: GrantFiled: August 28, 1995Date of Patent: January 21, 1997Assignee: Kabushiki Kaisha ToshibaInventors: Hajime Sumiyoshi, Takeshi Namikawa
-
Patent number: 5140421Abstract: A video signal processing pulse producing circuit for a video display device. The video signal includes a synchronizing signal and the device has at least one video processing element responsive to a pulse of a predetermined period. The circuit includes a circuit for generating the pulse in response to receipt of the synchronizing signal for controlling the signal processing element and a compensation circuit for generating an equivalent pulse having the predetermined period when receipt of the synchronizing signal by the pulse generating circuit is interrupted for maintaining continuous control of the video signal processing element.Type: GrantFiled: December 24, 1990Date of Patent: August 18, 1992Assignee: Kabushiki Kaisha ToshibaInventor: Hajime Sumiyoshi
-
Patent number: 5072298Abstract: An auto-tuning circuit for automatically adjusting the transfer function of an active filter for processing video signals. A voltage-controlled filter is used as active filter, for imparting a predetermined transfer characteristic to a signal having a component related to a television signal. The transfer characteristic can be adjusted in accordance with a voltage. The auto-tuning circuit comprises PLL section connected to the voltage-controlled filter, and switching circuit. The PLL section applies to the voltage-controlled filter a control voltage corresponding to the phase difference between a reference signal and an output signal obtained by passing the reference signal through the voltage-controlled filter. The switching section allows transfer of signals between the voltage-controlled filter and the PLL section for at least one of the horizontal blanking period and vertical blanking period of the television signal.Type: GrantFiled: September 28, 1990Date of Patent: December 10, 1991Assignee: Kabushiki Kaisha ToshibaInventor: Hajime Sumiyoshi
-
Patent number: 4882624Abstract: A synchronizing signal separation circuit for separating a composite synchronizing signal having a variable peak voltage subject to changes from a composite video signal, the composite synchronizing signal including a vertical synchronizing signal having a predetermined level for controlling vertical scanning in a television receiver. The separation circuit includes a composite separation circuit for separating the composite synchronizing signal from the composite video signal received from a source of video signals and a charge control circuit for maintaining the stability and the predetermined level of the vertical synchronizing signal after changes in synchronizing signal peak voltage.Type: GrantFiled: March 11, 1988Date of Patent: November 21, 1989Assignee: Kabushiki Kaisha ToshibaInventor: Hajime Sumiyoshi
-
Patent number: 4647970Abstract: A sync signal reproducing circuit for television receivers.Type: GrantFiled: December 20, 1985Date of Patent: March 3, 1987Assignee: Kabushiki Kaisha ToshibaInventor: Hajime Sumiyoshi