Patents by Inventor Masaaki Kitazima

Masaaki Kitazima 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: 5537054
    Abstract: A testing method is provided for a semiconductor device which includes a control terminal and a pair of main terminals wherein one of the main terminals is isolated from the outside by a dielectric. First, a voltage which changes with time is applied to the isolated main terminal through the dielectric. A control signal which controls conduction and non-conduction of the semiconductor device is the applied to the control terminal. Following this, the test is made by detecting a displacement current flowing through at least one of the two main terminals and the control terminal.
    Type: Grant
    Filed: March 10, 1986
    Date of Patent: July 16, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Masayoshi Suzuki, Jun-ichi Ohwada, Masaaki Kitazima, Hideaki Kawakami, Kenkichi Suzuki
  • Patent number: 5287095
    Abstract: A display device suitable for a high speed operation liquid crystal display device includes a matrix circuit having a plurality of signal lines, scanning lines disposed so as to intersect the signal lines and pixels provided at the positions corresponding to the intersections of the signal lines and the scanning lines; and a switching circuit for incorporating picture signals provided in correspondance to the signal lines, wherein the adjacent switching circuits are both turned on simultaneously.
    Type: Grant
    Filed: December 9, 1991
    Date of Patent: February 15, 1994
    Assignee: Hitachi, Ltd.
    Inventors: Masaaki Kitazima, Masahiro Eto, Hiroshi Jitsukata
  • Patent number: 4770502
    Abstract: A liquid crystal matrix driving method capable of shortening the re-write time of a picture surfaces is disclosed. In accordance with this method, pixels are brought to the light ON state or OFF state by changing in advance the light transmission state by utilizing the bistability of the display of the ferroelectric liquid crystal, a voltage keeping the light ON state or an OFF voltage is then applied to the pixels when they are already in the ON state in accordance with a time-division driving method such as line sequence scanning driving or dot sequence scanning driving, and a voltage keeping the OFF state or an ON voltage is applied when the pixels are already in the OFF state.
    Type: Grant
    Filed: January 6, 1987
    Date of Patent: September 13, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Masaaki Kitazima, Katsumi Kondo
  • Patent number: 4750813
    Abstract: A display device consisting of a plurality of scanning electrodes, a plurality of signal electrodes, a driving circuit feeding these electrodes with a scanning voltage and a signal voltage applied thereto, display elements having a pair of electrodes opposite to each other, which are disposed on the intersecting portion of the signal electrodes with the scanning electrodes, and switching elements controlling the feeding of one of the electrodes with the signal voltage, depending on the scanning voltage, comprises further a delaying circuit, which retards the timing of applying the signal voltage applied to a part of the signal electrodes, which are distant from the input terminal of the scanning voltage, with respect to the timing of applying the scanning voltage applied to the scanning electrodes.
    Type: Grant
    Filed: February 19, 1987
    Date of Patent: June 14, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Jun-ichi Ohwada, Masaaki Kitazima, Sakae Someya
  • Patent number: 4649517
    Abstract: An information holding device comprises a pair of substrates having a first electrode and a second electrode oppositely formed on opposing surfaces thereof, and a dielectric material held between the pair of substrates. A capacitance of the dielectric material between the first and second electrodes is changed and a voltage varying with time is applied to the dielectric. A displacement current flowing through the dielectric is then detected.
    Type: Grant
    Filed: February 24, 1984
    Date of Patent: March 10, 1987
    Assignee: Hitachi, Ltd.
    Inventors: Masaaki Kitazima, Hideaki Kawakami, Yoshiharu Nagae
  • Patent number: 4532506
    Abstract: A matrix display comprises: a plurality of picture cells generally arranged in a matrix, the picture cells being defined by a plurality of first electrodes arranged on a first substrate and at least one common electrode arranged on a second substrate and a display medium held therebetween; a plurality of first signal lines and a plurality of second signal lines crossing to the first signal lines, arranged on at least one of the first and second substrates; a plurality of first semiconductor switches each having a control terminal, a first main terminal and a second main terminal, a plurality of second semiconductor switches each having a control terminal, a first main terminal and a second main terminal, and a plurality of storage means, arranged at respective crosspoints of the first signal lines and the second signal lines; each of the first signal lines being connected to the control terminal of the associated one of the first semiconductor switches and the first main terminal of the associated one of the
    Type: Grant
    Filed: September 29, 1982
    Date of Patent: July 30, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Masaaki Kitazima, Hideaki Kawakami
  • Patent number: 4380008
    Abstract: Disclosed is a method of driving a matrix type display panel which includes a phase transition liquid crystal layer sandwiched between a pair of electrode groups arranged in the form of a matrix and including at least one transparent electrode group, and employs intersecting portions of said electrode groups as display segments for displaying information by driving one electrode group with the one-line-at-a-time scanning system; wherein a write-in voltage signal having a sufficient root mean square value for the phase transition of the liquid crystal layer and an erasing voltage substantially equal to OV are employed to drive the panel, and segments just subjected to scanning are applied with the write-in voltage signal when information is written in the segments and are applied with the erasing voltage when information written in the segments is erased.
    Type: Grant
    Filed: October 1, 1979
    Date of Patent: April 12, 1983
    Assignee: Hitachi, Ltd.
    Inventors: Hideaki Kawakami, Masaaki Kitazima, Naoyuki Izaki, Yoshiharu Nagae
  • Patent number: 4062626
    Abstract: A liquid crystal display device in which an electronic switch having a double threshold characteristic is combined with each of a plurality of liquid crystal cells, and an ac signal voltage and an ac bias voltage are applied to one and the other terminals respectively of the combined circuit of the liquid crystal cells and electronic switches. In the device, the electronic switches are turned on or off depending on the relation between the phase of the signal voltage and that of the bias voltage so that the liquid crystal cells can be excited for display by the voltage applied thereacross in response to the turn-on of the electronic switches.
    Type: Grant
    Filed: September 5, 1975
    Date of Patent: December 13, 1977
    Assignee: Hitachi, Ltd.
    Inventors: Hideaki Kawakami, Yutaka Yoneda, Yoshiharu Nagae, Masaaki Kitazima