Takehisa Sato

Bio: Takehisa Sato is an academic researcher. The author has contributed to research in topics: Gate driver & Oxide thin-film transistor. The author has an hindex of 7, co-authored 11 publications receiving 1150 citations.

15.2: Development of Driver‐Integrated Panel Using Amorphous In‐Ga‐Zn‐Oxide TFT

Abstract: We designed, prototyped, and evaluated LCD integrated with a gate driver and a source driver using amorphous In-Ga-Zn-Oxide TFTs having bottom-gate bottom-contact structure, thereby obtaining TFTs with superior characteristics Then, we prototyped the world's first 4-inch QVGA LCD and integrated the gate driver and source driver on the display panel

Wireless communication device

Abstract: It is an object of the present invention to facilitate charge of a battery of a wireless communication device. In addition, it is another object of the present invention to provide a wireless communication device capable of transmitting and receiving individual information without battery replacement which is required due to the power consumption of a battery. A wireless communication device includes a plurality of antenna circuits and a plurality of batteries electrically connected to any one of the plurality of antenna circuits through a switch, where the plurality of batteries are each electrically connected to a different circuit, the plurality of antenna circuits receive electric waves so that the plurality of batteries electrically connected to the plurality of antenna circuits are charged, and at least one of the plurality of antenna circuits receives an electric wave having a different frequency.

Development of Liquid Crystal Display Panel Integrated with Drivers Using Amorphous In–Ga–Zn-Oxide Thin Film Transistors

Abstract: We designed, prototyped, and evaluated a liquid crystal panel integrated with a gate driver and a source driver using amorphous In–Ga–Zn-oxide thin film transistors (TFTs). Using bottom-gate bottom-contact (BGBC) thin film transistors, superior characteristics could be obtained. We obtained TFT characteristics with little variation even when the thickness of the gate insulator (GI) film was reduced owing to etching of source/drain (S/D) wiring, which is a typical process for the BGBC TFT. Moreover, a favorable ON-state current was obtained even when an In–Ga–Zn-oxide layer was formed over the S/D electrode. Since the upper portion of the In–Ga–Zn-oxide layer is not etched, the BGBC structure is predicted to be effective in thinning the In–Ga–Zn-oxide layer in the future. Upon evaluation, we found that the prototyped liquid crystal panel integrated with the gate and source drivers using the TFTs with improved characteristics had stable drive.

Semiconductor device, communication system, and method of charging the semiconductor device

Abstract: An object of the present invention to provide a semiconductor device including a battery that can be wirelessly charged, in which the battery can be charged even when the semiconductor device is not put close to a power feeder. Such a semiconductor device has a structure including an antenna circuit, a communication control circuit to conduct wireless communication via the antenna circuit, a battery to be charged with electric power which is externally wirelessly fed via the antenna circuit, and an oscillator circuit to wirelessly feed electric power via the antenna circuit. In addition, the battery in the semiconductor device is wirelessly charged and the semiconductor device externally feeds electric power wirelessly to a chargeable battery in another semiconductor device.

18.4: 13.3‐inch 8k4k 664‐ppi Foldable OLED Display Using Crystalline Oxide Semiconductor FETs

Abstract: A prototype 13.3-inch 8k4k 664-ppi high-resolution foldable OLED display is constructed. C-axis aligned crystalline In—Ga—Zn oxide (CAAC-IGZO) FETs designed using a 1.5-µm rule process are used in the backplane. Each pixel circuit has three transistors and one capacitor, and an external circuit is used to correct pixel current.

Semiconductor device, and manufacturing method thereof

Abstract: An object is to provide a semiconductor device of which a manufacturing process is not complicated and by which cost can be suppressed, by forming a thin film transistor using an oxide semiconductor film typified by zinc oxide, and a manufacturing method thereof. For the semiconductor device, a gate electrode is formed over a substrate; a gate insulating film is formed covering the gate electrode; an oxide semiconductor film is formed over the gate insulating film; and a first conductive film and a second conductive film are formed over the oxide semiconductor film. The oxide semiconductor film has at least a crystallized region in a channel region.

Semiconductor device and display device

Abstract: An object of the present invention is to decrease the resistance of a power supply line, to suppress a voltage drop in the power supply line, and to prevent defective display. A connection terminal portion includes a plurality of connection terminals. The plurality of connection terminals is provided with a plurality of connection pads which is part of the connection terminal. The plurality of connection pads includes a first connection pad and a second connection pad having a line width different from that of the first connection pad. Pitches between the plurality of connection pads are equal to each other.

Method and apparatus for adaptive tuning of wireless power transfer

Abstract: Exemplary embodiments are directed to wireless power transfer. A transmit antenna generates an electromagnetic field at a resonant frequency of to create a coupling-mode region within a near field of the transmit antenna. A receive antenna receives the resonant frequency when it is within the coupling-mode region and resonates substantially near the resonant frequency. One, or both, of the transmit and receive antennas are tunable antennas that can be adaptively tuned. The adaptive tuning is accomplished by detecting a mismatch at the tunable antenna and generating a mismatch signal responsive to a voltage standing wave ratio at the tunable antenna. A resonance characteristic of the tunable antenna can be modified by adjusting a capacitance of a variable capacitor network connected to the tunable antenna.

Wireless power transfer for vehicles

Abstract: Exemplary embodiments are directed to wireless power transfer. A power transmitting device is attached to an existing vehicle item or is embedded in a vehicle element. The power transmitting device includes a transmit antenna to wirelessly transfer power to a receive antenna by generating a near-field radiation within a coupling-mode region. An amplifier applies a driving signal to the transmit antenna. A presence detector may detect a presence of a receiver device within the coupling-mode region. The presence detector may also detect a human presence. An enclosed compartment detector may detect when the vehicle element is in a closed state. A power output may be adjusted in response to the closed state, the presence of a receiver device, and the presence of a human.

Optimization of wireless power devices

Abstract: Exemplary embodiments are directed to wireless power. A chargeable device may comprise receive circuitry for coupling to a receive antenna. The receive circuitry may comprise at least one sensor to sense one or more parameters associated with the chargeable device. Further, the receive circuitry may comprise a tuning controller operably coupled to the at least one sensor to generate one or more tuning values in response to the one or more sensed parameters. Additionally, the receive circuitry may comprise a matching circuit operably coupled to the tuning controller for tuning the receive antenna according to the one or more tuning values.