Patents by Inventor Yuhichiroh Murakami

Yuhichiroh Murakami 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: 8269713
    Abstract: In one embodiment of the present invention, a unit circuit of a shift register includes a bootstrap circuit configured with a transistor T1, a transistor T2 and a capacitor, a transistor T3, a transistor T4, and a reset signal generation circuit. By use of two-phase clock signals and whose high level periods do not overlap with each other, the reset signal generation circuit generates a reset signal which is at a high level in a normal state and changes to a low level when an input signal turns into the high level. During a period that the reset signal is at the high level, transistors T3 and T4 perform discharge of a node and pull-down of an output signal. Thus, it is possible to obtain a power-saving shift register that fixes an output signal at a low level in a normal state without allowing a through current to flow therein.
    Type: Grant
    Filed: May 15, 2008
    Date of Patent: September 18, 2012
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Shige Furuta, Yuhichiroh Murakami, Yasushi Sasaki, Shinsaku Shimizu
  • Patent number: 8248348
    Abstract: A level shift circuit includes first and second level shifters which respectively output first and second output signals that are produced by level shifting two kinds of input clock signals whose high level periods do not overlap. The level shift circuit also includes control transistors and control lines which, together, prevent a feedthrough current from flowing into the second level shifter when the first output signal is high level, and prevent a feedthrough current from flowing into the first level shifter when the second output signal is high level, so as to suspend the level shift operation of the first and second level shifters. With the level shift circuit, power consumption during a specific time period in a non-active period of the clock signal can be eliminated, where the specific time period of one clock signal is the active period of the other clock signal.
    Type: Grant
    Filed: June 19, 2007
    Date of Patent: August 21, 2012
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yuhichiroh Murakami, Seijirou Gyouten, Hajime Washio, Eiji Matsuda, Sachio Tsujino, Shunsuke Hayashi
  • Publication number: 20120206510
    Abstract: A display device employing CC driving switches from (i) a first mode in which to carry out a display by converting resolution of a video signal by a factor of 2 in a column-wise direction to (ii) a second mode in which to carry out a display at the resolution of the video signal. During the first mode, signal potentials having the same polarity and the same gray scale are supplied to pixel electrodes included in respective two pixels that correspond to two adjacent scanning signal lines and that are adjacent to each other in the column-wise direction, and a direction of change in the signal potentials written to the pixel electrodes varies every two adjacent rows (2-line inversion driving). During the second mode, the direction of change in the signal potentials written to the pixel electrodes lines varies every single row (1-line inversion driving).
    Type: Application
    Filed: June 4, 2010
    Publication date: August 16, 2012
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Shige Furuta, Etsuo Yamamoto, Yuhichiroh Murakami, Seijirou Gyouten
  • Publication number: 20120200614
    Abstract: In a display device (i) which carries out a display based on a video signal whose resolution has been converted to higher resolution (high-resolution conversion driving) and (ii) which carries out CC driving, when the resolution of the video signal is converted by a factor of 2 (double-size display), assuming that a direction in which the gate lines extend is a row-wise direction, signal potentials having the same polarity and the same gray scale are supplied to pixel electrodes included in respective two pixels that correspond to two adjacent gate lines and that are adjacent to each other in the column-wise direction (scanning direction), and a direction of change in the signal potentials written to the pixel electrodes from the source lines varies every two adjacent rows according to the polarities of the signal potentials.
    Type: Application
    Filed: June 2, 2010
    Publication date: August 9, 2012
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Etsuo Yamamoto, Shige Furuta, Yuhichiroh Murakami, Seijirou Gyouten
  • Publication number: 20120200549
    Abstract: Provided is a display device which can prevent screen noise caused such that a potential of a common electrode is reversed after a memory mode enters from a refresh period to an entire write-in period, and a method for driving the display device. The memory mode includes (i) an entire write-in period in which a potential of the common electrode (COM) is fixed and the display data is written into all the memory circuits (node (PIX)) in each row and (ii) a refresh period in which the display data which has been written during the entire write-in period is refreshed at least once while the common electrode (COM) is driven. In the memory mode, the potential of the common electrode during the entire write-in period being a potential which the common electrode having been driven had at the end of a refresh period preceding the entire write-in period.
    Type: Application
    Filed: April 23, 2010
    Publication date: August 9, 2012
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Yasushi Sasaki, Yuhichiroh Murakami, Shige Furuta, Seijirou Gyouten, Shuji Nishi
  • Publication number: 20120188218
    Abstract: A memory-type liquid crystal display device includes a liquid crystal panel including memory circuits, and conducts a refresh operation more than once during a display holding period after rewriting of a screen. The memory-type liquid crystal display device increases at least one of (i) a frequency at which the screen is rewritten and (ii) a frequency at which the refresh operation is conducted during the display holding period as an intensity of light received by the liquid crystal panel increases. This allows the memory-type liquid crystal display device to reduce power consumption while keeping its display quality.
    Type: Application
    Filed: June 25, 2010
    Publication date: July 26, 2012
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Takuya Hachida, Yasushi Sasaki, Yuhichiroh Murakami, Shuji Nishi, Seijirou Gyouten
  • Patent number: 8223112
    Abstract: At least one embodiment of the present invention is directed to, even when external noise is applied to a shift register during all-on operation, preventing through-current from flowing in unit circuits and also to prevent increase in load on all-on control signal lines. When a high-level all-on control signal is provided to a unit circuit of a shift register, a transistor T3 is brought into off-state, so that a transistor T2 cannot output an on-voltage to a first output terminal. However, a transistor T24 is brought into on-state, so that the first output terminal outputs an on-voltage to the exterior. On the other hand, a transistor T32 is brought into on-state, so that a second output terminal outputs an off-voltage to a unit circuit 11 in the next stage. At this time, the transistor T3 is kept in off-state, so that no through-current flows to the transistors T24 and T3.
    Type: Grant
    Filed: August 18, 2008
    Date of Patent: July 17, 2012
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Hiroyuki Ohkawa, Shige Furuta, Yasushi Sasaki, Yuhichiroh Murakami
  • Publication number: 20120176393
    Abstract: Provided is a memory device that allows an amount of leakage into a first retaining section to which a binary logic level is written to be balanced between different circuit states. A predetermined period is set in which in a state where a first control section turns off an output element, (i) a first retaining section and a second retaining section retain an identical binary logic level, (ii) an electric potential of a voltage supply is set to one of a first electric potential level and a second electric potential level, (iii) the other one of the first electric potential level and the second electric potential level is supplied from a column driver to a fourth wire, and (iv) subsequently the fourth wire is shifted to a floating state.
    Type: Application
    Filed: April 23, 2010
    Publication date: July 12, 2012
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Hiroyuki Ohkawa, Yasushi Sasaki, Yuhichiroh Murakami, Shige Furuta, Seijirou Gyouten, Shuji Nishi
  • Publication number: 20120176388
    Abstract: In a memory liquid crystal display device, a potential of a storage capacitor line signal (CS) supplied to the CS lines (CSL(i)) are once decreased (?Vcs) while the gate lines (GL(i)) are made simultaneously active (period t4, period t10) in the data holding period (T2), and the potential of the storage capacitor line signal (CS) is made back to its original potential while the gate lines (GL(i)) are made simultaneously inactive and the refresh output control lines (RC(i)) are made active (period t5, period t11). This reduces flicker, thereby allowing for improvement in display quality of the memory liquid crystal display device.
    Type: Application
    Filed: May 26, 2010
    Publication date: July 12, 2012
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Makoto Yokoyama, Shige Furuta, Yuhichiroh Murakami, Yasushi Sasaki, Seijirou Gyouten, Shuji Nishi
  • Publication number: 20120179923
    Abstract: A memory device can perform a first operation mode in which a discrete level is supplied to cause the memory cell to retain a logical level, and prevent unnecessary power consumption due to an operation of a power source which is unnecessary in the first operation mode. The memory device includes: a first power source (VDD) for supplying a first potential level; a second power source (VSS) for supplying a second potential level, a third power source (GVDD) for supplying a potential higher than a highest potential of discrete levels; and a fourth power source for supplying a potential lower than a lowest potential of the discrete levels, the first and second potential levels being used to supply the discrete levels, when the first operation is carried out, VDD, VSS, and GVDD being caused to be in operation and the fourth power source being stopped from being in operation.
    Type: Application
    Filed: March 18, 2010
    Publication date: July 12, 2012
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Yasushi Sasaki, Yuhichiroh Murakami, Shige Furuta, Seijirou Gyouten, Shuji Nishi
  • Publication number: 20120169579
    Abstract: A transistor (N1) has a gate terminal connected to a word line (Xi(1)) and a first conduction terminal connected to a bit line (Yj). A transistor (N2) has a gate terminal connected to the word line (Xi(2)) and a first conduction terminal connected to a node (PIX). A transistor (N3) has a gate terminal connected to a node (MRY) and a first conduction terminal connected to the word line (Xi(2)). A transistor (N4) has a gate terminal connected to the word line (Xi(3)), a first conduction terminal connected to a second conduction terminal of the transistor (N3), and a second conduction terminal connected to the node (PIX). Capacitors (Ca1), (Cb1), (Cap1) are formed between the node (PIX) and a reference electric potential wire (RL1), between the node (MRY) and the reference electric potential wire (RL1), and between the first conduction terminal of the transistor (N3) and the node (MRY), respectively.
    Type: Application
    Filed: May 18, 2010
    Publication date: July 5, 2012
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Shuji Nishi, Yuhichiroh Murakami, Shige Furuta, Yasushi Sasaki, Seijirou Gyouten
  • Publication number: 20120169580
    Abstract: A memory liquid crystal display device includes a transistor (N1), a transistor (N2), a transistor (N3), a transistor (N4), a first storage capacitor (storage capacitor of an overlapping part of a capacitor electrode 37a and a CS line CSL(i)) connected to a pixel electrode (7), and a second storage capacitor (storage capacitor of an overlapping part of a capacitor electrode 37b and a CS extension section 10bb) connected to the pixel electrode (7) via the transistor (N2), the pixel electrode (7) being connected to (a) a source line (SL(j)) via the transistor (N1), (b) a data transfer control line (DT(i)) via the transistor (N4) and the third transistor, (c) a drain electrode (9a) of the transistor (N1) via a contact hole (13), and (d) a source electrode (8b) of the transistor (N2) and to a drain electrode (9c) of the transistor (N4), via a contact hole (14).
    Type: Application
    Filed: May 18, 2010
    Publication date: July 5, 2012
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Shuji Nishi, Seijirou Gyouten, Yuhichiroh Murakami, Shige Furuta, Yasushi Sasaki
  • Publication number: 20120169753
    Abstract: A memory device is provided which includes a memory circuit that allows a circuit which carries out a refresh operation to suitably carry out an original operation of the circuit even if an off-leakage current occurs in a transfer element used in a transfer section. A memory cell includes a switching circuit, a first retaining section, a transfer section, a second retaining section, a first control section, and a voltage supply, and the first control section is controlled to be in (i) a state in which the first control section carries out a first operation in which the first control section is in an active state or a non-active state and (ii) a state in which the first control section carries out a second operation.
    Type: Application
    Filed: April 23, 2010
    Publication date: July 5, 2012
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Yuhichiroh Murakami, Shige Furuta, Yasushi Sasaki, Seijirou Gyouten, Shuji Nishi
  • Publication number: 20120169750
    Abstract: Provided are a memory-type display device capable of improving image quality during a normal mode and a method for driving such a display device. Each memory circuit (MR1) includes: a node (PIX) (pixel electrode); a node (MRY) (memory electrode); a switch circuit (SW1); a first data-retention section (DS1) composed of a capacitor (Ca1); a data transfer section (TS1) composed of a transistor (N2); a second data-retention section (DS2) composed of a capacitor (Cb1); and a refresh output control section (RS1) including a transistor (N4). During the normal mode, and the capacitor (Ca1) and the capacitor (Cb1) are both used as auxiliary capacitors with the transistor (N2) in a conductive state and the transistor (N4) in a cutoff state.
    Type: Application
    Filed: April 23, 2010
    Publication date: July 5, 2012
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Yuhichiroh Murakami, Yasushi Sasaki, Shige Furuta, Seijirou Gyouten, Shuji Nishi
  • Publication number: 20120169751
    Abstract: In an active matrix display apparatus including: pixels provided in a matrix pattern, the pixels each including a memory circuit which retains data while refreshing the data, a data signal electric potential which is supplied from a source line in a period t1 and written to a node which is connected to a liquid capacitor is higher than a data electric potential of the node, the data electric potential being obtained in a period t14 after a refresh operation of the memory circuit.
    Type: Application
    Filed: May 18, 2010
    Publication date: July 5, 2012
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Etsuo Yamamoto, Yasushi Sasaki, Yuhichiroh Murakami, Shige Furuta, Seijirou Gyouten, Shuji Nishi
  • Publication number: 20120169690
    Abstract: Provided are a display device capable of preventing image noise arising from changes in potential of a common electrode and auxiliary capacitor lines at the time of a switch between a normal mode and a memory mode and a method for driving such a display device. In a case where it is necessary to cause the common electrode and the auxiliary capacitor lines to change in potential along with a switch between the normal mode and the memory mode, the change in potential is made while electrically connecting a node of each memory circuit to a corresponding source line with the corresponding source line having its potential fixed and with the memory circuit having its a switch circuit in a conductive state.
    Type: Application
    Filed: April 23, 2010
    Publication date: July 5, 2012
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Yasushi Sasaki, Yuhichiroh Murakami, Shige Furuta, Seijirou Gyouten, Shuji Nishi
  • Patent number: 8174479
    Abstract: In one embodiment of the present invention, the present shift register is a shift register provided in a display device by which a partial-screen display is available. The shift register includes a shift stopping circuit that is provided in an in-between stage, and stops operation of the shift register between a first stage and a last stage of the shift register in partial-screen display. The shift register also includes a circuit that is provided in a stage other than the in-between stage in such a manner that the circuit does not perform signal processing but serves as a signal path. The circuit is same as the shift stopping circuit in configuration. The foregoing allows improvement in display quality of the display device employing the present shift register.
    Type: Grant
    Filed: June 12, 2006
    Date of Patent: May 8, 2012
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yuhichiroh Murakami, Seijirou Gyouten, Noboru Matsuda, Hajime Washio
  • Publication number: 20120105395
    Abstract: A stage of the shift register has (i) a set-reset type flip-flop which receives an initialization signal and (ii) a signal generating circuit which receives a simultaneous selection signal and which generates an output signal by use of an output of the flip-flop. In at least one example embodiment, the output of the flip-flop becomes inactive regardless of whether a setting signal and a resetting signal are active or inactive, as long as the initialization signal is active. The initialization signal becomes active before the end of the simultaneous selection, and then becomes inactive after the end of the simultaneous selection. This makes it possible to stabilize operation of the shift register after the end of simultaneous selection of a plurality of signal lines carried out by the display driving circuit at a predetermined timing.
    Type: Application
    Filed: March 18, 2010
    Publication date: May 3, 2012
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Takuya Hachida, Yuhichiroh Murakami, Shige Furuta, Makoto Yokoyama, Yasushi Sasaki
  • Publication number: 20120092323
    Abstract: A flip-flop includes: a first, second, third, and fourth transistors; input terminals; and first and second output terminals, the first and second transistors constituting a first CMOS circuit such that gate terminals are connected and drain terminals are connected, the third and fourth transistors constituting a second CMOS circuit such that gate terminals are connected and drain terminals are connected, the first output terminal connected to a gate side of the first CMOS circuit and a drain side of the second CMOS circuit, the second output terminal connected to a gate side of the second CMOS circuit and a drain side of the first CMOS circuit, at least one input transistor included in the group of the first through fourth transistors, a source terminal of the input transistor being connected to one of the input terminals. This can provide a further compact flip-flop.
    Type: Application
    Filed: March 26, 2010
    Publication date: April 19, 2012
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Yuhichiroh Murakami, Shige Furuta, Yasushi Sasaki, Makoto Yokoyama, Takahiro Yamaguchi
  • Publication number: 20120092311
    Abstract: Disclosed is a shift register for use in a display driving circuit that simultaneously selects signal lines, including, in a stage thereof: a flip-flop including an initialization terminal; and a signal generating circuit that receives a simultaneous selection signal and that generates an output signal of the stage by use of an output of the flip-flop, wherein: the output signal of the stage becomes active due to an activation of the simultaneous selection signal so as to be active during a period of the simultaneous selection; the output of the flip-flop is non-active while the initialization terminal, a set terminal, and a reset terminal of the flip-flop; and the initialization terminal of the flip-flop receives the simultaneous selection signal. This shift register makes it possible to downsize various drivers.
    Type: Application
    Filed: March 18, 2010
    Publication date: April 19, 2012
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Hiroyuki Ohkawa, Yasushi Sasaki, Yuhichiroh Murakami, Shige Furuta, Makoto Yokoyama