Sharp Kabushiki Kaisha Corporation

Masahiro Ise

Katsuyuki Machino

Hidehiko Tanaka

Toshiyuki Matsubara

Teiji Terasaka

Yoshiharu Kanatani

Etsuo Mizukami

Chuji Suzuki

Takeshi Seike

Kenzo Inazaki

Takaaki Okamoto

Koichi Kajimoto

Kenzoo Inazaki

Katsuyuki Machimno

Kenzoh Inazaki

Tsuneyuki Iwano

A method of driving a display device having a plurality of signal electrode lines, a plurality of scanning electrode lines, and a display element and a 2-terminal type non-linear element connected to each other in series between each signal electrode line and each scanning electrode line, in which a selected period is divided into a writing period for charging the display element with more than a certain amount of charge through the 2-terminal type non-linear element and an erasing period following the writing period, and a second voltage which has a polarity reverse to that of the first voltage and does not erase the charge charged in the writing period is applied in the erasing period to turn on the display element. The after-images can be reduced significantly, and the tolerance of the second voltage required to obtain high-contrast can be broadened.

Method of driving display device

A driving method which is used for a display device and which applies different voltages to display elements during the first through third periods in a selection period. During the first period, a first voltage having not less than a predetermined value is applied to each display element through a non-linear element of two-terminal type. During the second period, a second voltage having a level that does not cancel the first voltage is applied upon on-time, while a second voltage having a level that cancels the first voltage is applied upon off-time. During the third period, a third voltage that has an opposite polarity to the first voltage upon on-time and that has the same polarity as the first voltage upon off-time is applied. Here, the third voltage has a non-selection level upon on-time as well as off-time. Thus, an effective voltage, which is applied to the display element selected during the selection period, becomes virtually the same irrespective of display states. Thus, the influence of data during the non-selection period hardly appear on the display during the selection period. This makes it possible to reduce generation of crosstalk to a great degree. Since the voltage to be applied to the display element is higher than a predetermined voltage, it is possible to reduce the dependance of the characteristic shift of the non-linear element on display states, and consequently to suppress afterimages and seizures.

Driving method for a liquid crystal display

The invention provides a voltage-generating circuit in which the characteristic of the output voltage in response to the ambient temperature is represented by a predetermined line. A temperature sensor outputs a voltage in proportion to the ambient temperature, and the voltage is inversely amplified by an operational amplifier. An optimum operating voltage V.sub.op for a liquid crystal is output from an output terminal of a variable voltage regulator, in response to the voltage output ted from the operational amplifier.

Temperature compensation voltage-generating circuit

A tablet integrated with a display comprising a matrix panel having row and column electrodes, a detecting conductor, a row electrode driver, a column electrode driver, a row coordinate detecting circuit and a column coordinate detecting circuit, in case of display mode, the row electrode driver applying the row scanning pulse successively to every row electrode of the matrix panel from one to another, and the column electrode driver applying voltage in accordance with the display data simultaneously to the column electrode of the matrix panel each time the row scanning pulse is applied successively to the row electrode of the matrix panel, in case of row detection mode, the row electrode driver applying the row scanning pulse successively to the row electrode of the matrix panel, and receiving the row scanning pulse detected through electrostatic capacitive coupling caused by the detecting conductor touching an arbitrary position on the matrix panel, so as to present the row coordinate of the position which the detecting conductor touches, and in case of column detection mode, the column electrode driver applying the column scanning pulse successively to the column electrode of the matrix panel, and the column coordinate detecting circuit receiving the column scanning pulse detected through electrostatic capacitive coupling caused by the detecting conductor touching an arbitrary position on the matrix panel, so as to present the column coordinate of the position which the detecting conductor touches.

Tablet integrated with display

A drive voltage generating device for a liquid crystal display device includes a terminal voltage supply source for generating an output voltage of V.sub.S, an actuating voltage supply source for generating an output voltage of V.sub.E, and a plurality of circuit sections. Each circuit section is composed of a first capacitor for storing therein a charge supplied from the terminal voltage supply source, a second capacitor for storing therein a charge transferred from the first capacitor an output terminal section for receiving a voltage V.sub.S from the second capacitor and a switch for switching respective connections between the terminal voltage supply source and the first capacitor, and between the first and second capacitors. The switch is provided for switching between an operation for supplying a charge from the terminal voltage supply source to the first capacitor and an operation for transferring a charge stored in the first capacitor to the second capacitor.

Drive voltage generating device for liquid crystal display device

A tablet integrated with a display is provided comprising a matrix panel having row and column electrodes, a detecting conductor, a row electrode driver, a column electrode driver, and row and column coordinate detecting circuits. In a display mode, the row electrode driver applies a row scanning pulse successively to each row electrode of the matrix panel, and the column electrode driver simultaneously applies a display voltage to each column electrode of the matrix panel each time a corresponding row scanning pulse is applied. In a row detection mode, the row electrode driver applies the row scanning pulse successively to each row electrode of the matrix panel, and analyzes the timing of the row scanning pulse detected by a detecting conductor touching the matrix panel, so as to determine the row coordinate of the position of the detecting conductor. In a column detection mode, the column electrode driver applies the column scanning pulse successively to each column electrode of the matrix panel, and the column coordinate detecting circuit analyzes the timing of the column scanning pulse detected by the detecting conductor touching the matrix panel, so as to determine the column coordinate of the detecting conductor.

A very useful data transmission system having a plurality of transmission modules connected to a single cable in a multidrop manner is disclosed herein. The system features its ability to check the transmission state at the level of individual modules through use of a proper code notation (typically, Manchester code). The system detects a specific module with proper signals lasting at the same level for more than a given time, except cable outputs, and treats it as involving a faulty condition and compels the transmission state to a halt, thus preventing only the faulty module or modules from transmitting signals thereby avoiding breakdown of the whole system.

Data transmission system

A radio pager system and pager terminal apparatus used in the system are disclosed. A pager signal to be transmitted includes destination information and message specifying information for specifying a message to be transmitted. The pager terminal apparatus includes a receiver for receiving an incoming pager signal, a detector for detecting that the received pager signal is a signal destined for the pager terminal apparatus, an extracting circuit for extracting message specifying information from the pager signal transmitted to the pager terminal apparatus and message displaying apparatus responsive to the extracted message specifying information for displaying a message corresponding to the extracted message specifying information in a visually recognizable manner. The radio pager system includes the above pager terminal apparatus, a station for transmitting via radio a pager signal, and transmission terminal apparatus for supplying the destination information and the message information to the station. The data to be transmitted is not the body of the message but message specifying information, so that the amount of data to be transmitted is reduced and the communication is kept secret.

Radio pager system which transmits secret coded messages from a caller

The present disclosure is directed to an emergency access method in which in the event that an emergency data occurring at a particular terminal is fed immediately to a central system but collides with any emergency data from a different terminal such collision is sensed and a signal in that data is delayed in a random number manner through the use of an appropriate random number generating algorithm in order to avoid such collision within a short length of time.

Emergency access method in centralized monitoring system

A signal transmission system which constantly allows data with the top priority to pass preceding others in a bus-type network. In transmitting a packet consisting of a plurality of start-synchronized frames, the bus is monitored for a predetermined period after the first frame transmission. If a frame-start signal is detected during this predetermined period, the next frame is promptly transmitted synchronously with the detected frame-start signal. If no frame-start signal is detected during this period, the next frame is transmitted immediately after the predetermined period elapses. As a result, each frame by a transmitting terminal starts at the same time as that by another terminal. Therefore, so long as the clock pulse error between the different terminals is small enough to permit a frame transmission, the terminals can detect collision for each frame. As soon as either of the terminals detects collision, it stops data transmission, whereby a packet with the top priority is always permitted to pass.

Signal transmission system in a bus-type network

A data transmission method over building wiring includes a plurality of transmission sections. One of these sections is selected from the plurality of transmission sections to be a data transmission source machine for providing data. The data is transmitted from the data transmission source to the remaining transmission sections. If a transmission section is not selected it is used to relay the data to one of the remaining transmission sections wherein it is received by a final data transmission section. A data transmission section used in the method, comprises a data receiving part for receiving the transmitted data, a relay counter part for counting the number of relaying the transmitted data, and data relaying part for steps of relaying the-received data.

Data transmission system over building wiring

A signal transmission system utilizes the building or house wiring as the data transmission line. A frequency detection system is required to detect a frequency of the power voltage. The frequency detection system includes a zero-crossing detection circuit for developing a detection output when the zero-crossing is detected. A timer element is provided in the frequency detection system, which functions to neglect an output signal from the zero-crossing detection circuit for a preselected period of time after the last detection output has been developed from the zero-crossing detection circuit.

Power frequency detection system

This disclosure is directed to a data transmission system via the power supply line wherein it is characterized in that; it effectively controls branching terminal units connected to the CPU via the power supply line, by transmitting a high frequency AC signal that is mixed into the AC commercial frequency via the power supply line, while it normally surveilles the actual status of terminal units during normal operations. According to this system as a preferred embodiment of the present invention, after sampling data via the poling, a specific AC commercial frequency cyclic period can be allocated in order to properly transmit any emergency data between terminal units via a contention, and as a result, even in the slow-speed transmission line, not only any change of condition occurring in the terminal units can quickly be sent to the central processing unit, but all the control signals from the central processing unit can also be sent to respective terminal units without being held for waiting.

Growing community of inventors

Kashihara, Japan

Masahiro Ise