Diode Or Varistor Patents (Class 345/91)
  • Patent number: 5838290
    Abstract: A display device in which an internal auxiliary voltage, which is used for controlling, is obtained via photovoltaic converter.
    Type: Grant
    Filed: March 6, 1997
    Date of Patent: November 17, 1998
    Assignee: U.S. Philips Corporation
    Inventor: Karel E. Kuijk
  • Patent number: 5835073
    Abstract: An additional switching element (18) is associated with a switching element (8) in a display device (1), which additional switching element is short-circuited by a picture electrode (5) or row electrode (7) when the switching elements function normally, so that there is no voltage drop across the second switching element (18) when a pixel (11) operates satisfactorily. Consequently, the redundant element does not have any capacitive influence on the operation of the pixel or the transmission/voltage characteristic of the pixel. If the switching element (8) is defective, the second switching element (18) can be switched on.
    Type: Grant
    Filed: March 3, 1995
    Date of Patent: November 10, 1998
    Assignee: Flat Panel Display Co. B.V.
    Inventor: Hendrikus C. M. Van Doremalen
  • Patent number: 5812106
    Abstract: An active matrix display device, having an array of picture elements (12) comprising electro-optic, for example LC, display elements (14) and associated switching devices (15), for example thin film diodes, driven by selection and data signals applied to sets of row and column address conductors (16, 17) respectively, which includes a reference circuit (34) comprising a switching device (35) connected to a capacitive element (36) and similarly driven periodically by selection signals and a reference data signal applied via one of the column address conductors (17), and an adjustment circuit which senses the voltage at the capacitive element (36), indicative of the operational behavior of the switching device (35), at particular times corresponding substantially to the termination of a selection signal applied to the reference circuit and which, according to the sensed voltage at that time, is operable to adjust the drive voltages used for the picture elements (12) so as to compensate for changes in the operat
    Type: Grant
    Filed: November 21, 1996
    Date of Patent: September 22, 1998
    Assignee: U.S. Philips Corporation
    Inventor: John R. Hughes
  • Patent number: 5757349
    Abstract: An active matrix addressed liquid crystal display device includes: a plurality of data lines; a plurality of scan lines each intersected with each of the plurality of data lines; liquid crystal elements each provided to each intersecting point of the plurality of data lines and scan lines; two-terminal switching elements each provided to each intersecting point of the plurality of data lines and scan lines; a data line drive unit for generating data signals to drive the data lines; and a scan line drive unit for generating scan signals to drive the scan lines. The scan signals are formed of a selecting term, a current applying term preceding the selecting term, and a holding term following the selecting term. The current applying term is formed by more than three current applying small terms. The three small terms are formed by the same polarity of potential as that of the selecting term, and by the polarity of potential opposite to that of the selecting term.
    Type: Grant
    Filed: November 7, 1995
    Date of Patent: May 26, 1998
    Assignee: Citizen Watch Co., Ltd.
    Inventor: Seigo Togashi
  • Patent number: 5694146
    Abstract: An active matrix liquid crystal display panel including a plurality of Ovonic threshold switches each serially coupled between the corresponding row or column conductor and the liquid crystal display element. The Ovonic threshold switches act as display element selection devices and current isolation devices. The Ovonic switches have an off-state resistance of at least 1.times.10.sup.10 ohms.
    Type: Grant
    Filed: October 14, 1994
    Date of Patent: December 2, 1997
    Assignee: Energy Conversion Devices, Inc.
    Inventors: Stanford R. Ovshinsky, Wolodymyr Czubatyj, Rosa Young, Guy C. Wicker
  • Patent number: 5666131
    Abstract: A method of driving a two-terminal type active matrix liquid crystal display device while improving printing of image and residual image caused by the characteristics of the switching elements that change depending upon the current. The liquid-crystal display device has a plurality of data lines and scanning lines, and liquid-crystal pixels provided at the intersecting points of said data lines and said scanning lines, said liquid-crystal pixels having at least one two-terminal type switching element and being driven by a scanning signal applied to the scanning lines and by a data signal applied to the data lines. The scanning signal .phi.(n) has current application periods (27, 28, 32, 33) for flowing a current to the switching elements preceding the select periods (26, 31). The scanning signal further has holding periods after the select periods.
    Type: Grant
    Filed: January 26, 1996
    Date of Patent: September 9, 1997
    Assignee: Citizen Watch Co., Ltd.
    Inventor: Seigo Togashi
  • Patent number: 5610627
    Abstract: A clock generation circuit (23) is provided for use with a data display device and a calculation unit, with the calculation unit performing a calculation in a calculation mode resulting in data which is displayed on the data display device. The clock generation circuit generates a first clock signal (CK2) and a second clock signal (CK1). The second clock signal (CK1) is generated by a circuit (52) only during a calculation mode. A clock switching circuit (54) selects, in dependence upon whether the calculation mode is being executed, between a clock signal (CKD) derived from the signal (CK1) and an independently-produced clock signal (CKI) for use as the first clock signal (CK2). Thus, power is conserved by turning off the circuit (52) during a pure display mode and by turning off an oscillator (24) which generates the signal (CKI) during a calculation mode.
    Type: Grant
    Filed: February 10, 1994
    Date of Patent: March 11, 1997
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yoshimitsu Inamori, Koichi Oda
  • Patent number: 5576728
    Abstract: A driving method for an electooptical device is disclosed. A plurality of nonlinear resistance elements are arranged in units of pixel electrodes, and two adjacent operating electrodes are coupled through independent nonlinear resistance elements which are controlled by the pair of operating electrodes so as to provide a stable operation against variation in characteristics of the nonlinear resistance elements and to prevent deterioration of display over time. Data signals are applied to signal electrodes and are set in reference to nonselected scan signals applied to the scan electrodes during a nonselected period. Thus, the data input to one pixel is not affected by data input to the other pixels and is not affected during the period between a first frame scanning and a next frame scanning.
    Type: Grant
    Filed: October 6, 1993
    Date of Patent: November 19, 1996
    Assignee: Seiko Instruments Inc.
    Inventor: Takeshi Maeda
  • Patent number: 5561441
    Abstract: A liquid crystal display panel of the active matrix type which uses, as switching elements, non-linear resistance elements that exhibit asymmetric non-linear characteristics depending upon the polarity of the applied voltage, without causing flickering or scorching of the display. The amplitude of the data signal is changed depending on the characteristics of the non-linear resistance element, such as a2 in the positive-side field and b2 in the negative-side field, and the panel is driven in a manner that the transmission factor modulation range is the same in the positive-side field and in the negative-side field. In the gradation display based on the pulse width modulation, the pulse width is adjusted depending on the non-linear characteristics in the positive-side field and in the negative-side field, such that the relationship between the degree of gradation and the transmission factor is the same on the positive side and on the negative side.
    Type: Grant
    Filed: December 13, 1994
    Date of Patent: October 1, 1996
    Assignee: Citizen Watch Co., LTD.
    Inventor: Yasukazu Hamano
  • Patent number: 5504365
    Abstract: A spatial light modulation device, in which at least a photoconductor structure and a light modulator have a multilayer structure. In this spatial light modulation device, the photoconductor structure has a plurality of pixel portions and avalanche multiplication of charges generated by light incident on each of the pixel portions is performed therein and charges obtained as a result of the avalanche multiplication are stored in the pixel portions. Thus, this spatial light modulation device has high sensibility.
    Type: Grant
    Filed: January 21, 1994
    Date of Patent: April 2, 1996
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Tetsuhiro Yamazaki, Atushi Nakano, Yuuichi Kuromizu
  • Patent number: 5483085
    Abstract: An electro-optic integrated circuit including an addressable array of light emitting devices, a column decoder and a plurality of address lines formed on the substrate. There are address lines each including an external connection pad. The decoder includes a switching circuit connected to each column for activating the column and a plurality of sets of diodes connected to the address lines and the switching circuits so that each set of diodes has a unique code produced by a combination of diodes in that set .and the address lines to which the diodes in that set are connected.
    Type: Grant
    Filed: May 9, 1994
    Date of Patent: January 9, 1996
    Assignee: Motorola, Inc.
    Inventors: Paige M. Holm, George W. Rhyne, Thomas J. Walczak
  • Patent number: 5424753
    Abstract: A display device has first and second substrates, a liquid-crystal layer, pixel electrodes arranged on the first substrate, a plurality of semiconductor active elements connected to the pixel electrodes, signal lines for supplying drive signals to the active elements, and a plurality of opposing electrodes arranged on the second substrate. Each pixel electrode, that portion of each opposing electrode which overlaps the pixel electrode, and that portion of the liquid-crystal layer which is sandwiched between the pixel electrode and said that portion of the opposing electrode form a pixel. A voltage having a positive or negative value according to the image data is applied between the input terminal of the semiconductor active element and said at least one of the opposing electrode, for a selecting period.
    Type: Grant
    Filed: December 9, 1993
    Date of Patent: June 13, 1995
    Assignee: Casio Computer Co., Ltd.
    Inventors: Katsumi Kitagawa, Hiroyuki Okimoto, Shyunichi Sato
  • Patent number: 5396260
    Abstract: Mineral content in processed ore and coal content in coal slurries are determined using a video system. A video image is taken of a sample, the video image is digitized, and gray levels are assigned to points or areas on the video image. The distribution of the gray levels for the image provides an indication of the purity of the minerals in the ore sample. The mean gray level for the image provides an indication of the mineral content of interest in the sample. The video system should be calibrated using ores that normally occur in the process environment and using samples of controlled moisture content. The video system has particular utility in determining phosphate content and calcium ratio in phosphate ores.
    Type: Grant
    Filed: December 22, 1992
    Date of Patent: March 7, 1995
    Assignees: The Center for Innovative Technology, Virginia Polytechnic Institute & State University, Virginia Tech Intellectual Properties, Inc.
    Inventors: Gregory T. Adel, Roe-Hoan Yoon, Gerald H. Luttrell
  • Patent number: 5379050
    Abstract: In operation of an active matrix display device comprising an array of display elements (12), for example liquid crystal elements, each connected in series with an associated two terminal non-linear switching device (30), e.g. a MIM, between row and column address conductors (22,24), and row and column driver circuits (40,43) for applying selection signals to each row conductor in turn and data signals to the column conductors, the data signals are applied for part only of the row address period and a row selection signal commences prior to the data signal and while a reference potential is applied to the column conductors whereby during a row address period a display element is initially charged to a level approaching the lower end of the display element's operational range of voltages and thereafter charged to the required level according to the data signal. Vertical cross-talk is reduced and peak current density through the non-linear devices is kept low, thereby avoiding the risk of damage.
    Type: Grant
    Filed: November 26, 1991
    Date of Patent: January 3, 1995
    Assignee: U.S. Philips Corporation
    Inventors: Alexander D. Annis, Alan G. Knapp, Jeremy N. Sandoe, Peter B. A. Wolfs