Sharp Kabushiki Kaisha Corporation

Yoshiyuki Kokuhata

Masahiro Takahashi

Hisashi Uede

Toshihiro Ohba

Hiroshi Kishishita

Atsushi Sakamoto

Takeshi Seike

A method for driving a liquid crystal display apparatus including pixels, scanning lines, and data lines, includes the steps of: generating a data signal voltage to be applied to the data lines from a supply voltage; and correcting the supply voltage based on a temperature of the liquid crystal display apparatus.

Display apparatus and method for driving the same

A driving method is disclosed which prevents a remaining image from occurring at the time of turning off of the display device. In particular, the driving method for the display device is such that, when the power-supply signal is switched from ON state to OFF state, non-lit-up display data is outputted so that all the pixels are switched to the non-lit-up display. The display elements are maintained in the non-lit-up display state over the entire surface of the display up to completion of a period corresponding to a predetermined number of frames after the frame in which the power-supply OFF signal has been detected. The driving operation, which takes place immediately before the completion of the output of the non-lit-up display data within the non-display period, is maintained until the scanning start signal has risen, and the driver output control signal is switched from ON state to OFF state in synchronism with the rise of the scanning start signal.

Driving method for display and a liquid crystal display using such a method

A voltage generation circuit includes a potential line for a voltage value VA, a group of potential lines constituted by potential lines for voltage values V,VM and VS, respectively, a potential line for a voltage value VB, a first capacitor, a second capacitor having a capacitance equal to the capacitance of the first capacitor, a first switch for selectively connecting the first terminal of the first capacitor to the potential line and one potential line out of the group of potential lines, and a second switch for selectively connecting a second terminal of the first capacitor to the potential line that applies a potential symmetric to the potential of one predetermined potential line out of the group of potential lines and to the first terminal of the second capacitor. The second capacitor includes first and second terminals connected to the potential line for VB and the one potential line out of the group of the potential lines, respectively. Connection switching of the first and second switches is controlled so that the first and second capacitors are charged and discharged in a complementary manner.

Circuit for generating a constant voltage from a plurality of predetermined voltages using a capacitive element and switch, and a liquid crystal display apparatus employing such a circuit

In a display device such as a thin-film EL display device, etc. formed with a dielectric layer disposed between a plurality of scanning side electrodes and a plurality of data side electrodes in the direction for them intersecting to each other, a modulation voltage, varied according to gradation display data is applied to the data side electrodes, and a positive or negative writing voltage is applied to the scanning side electrodes in a line order for a gradation display different in brightness. Binary coded signals corresponding to each gradation of a gradation display are used as the gradation display data. The logical value of the binary coded signal is inverted according to the polarity of the writing voltage. Thus, a common gradation display can be performed from one binary coded signal for both the negative driving that applies a negative writing voltage and the positive driving that applies a positive writing voltage. As a result, by only by adding a data conversion circuit for inverting a binary coded signal, the function that converts the correspondence relation between the gradation to be displayed and the gradation display data depending on the negative driving or positive driving can be incorporated.

Method and apparatus for driving display device

A voltage generating circuit for driving a display device having a capacitive element, such as a liquid crystal display device, switches a switch between two terminals so as to output an input voltage V.sub.1 from one of the input terminals as it is in a period in which the switch is connected one of the terminals. In this period, a capacitor is charged. On the other hand, in a period in which the switch is connected to the other of the terminals, the voltage generating circuit outputs from the output terminal a voltage V.sub.2 as the sum voltage of the charged voltage (V.sub.1) on the capacitor and an input voltage V.sub.2 -V.sub.1 from the other of the input terminals. A reverse current flowing from the capacitive element of the display device through the output terminal is stored on the capacitor, and then used.

Voltage generating circuit and liquid crystal display device

In a method for driving a liquid crystal display device in which a scanning electrode signal and a data electrode signal are successively applied to a display panel where picture elements, which are arranged so that a liquid crystal element and a two-terminal non-linear element are connected in series, are arranged in a matrix-like pattern, a scanning electrode signal whose level is switched to a higher and lower levels than a reference level is applied during the selecting period for determining as to whether the picture element is turned on or off and a scanning electrode signal with the reference level is applied during non-selecting period. As a result, production of a residual image and occurrence of crosstalk can be lowered.

Method of driving liquid crystal display device and liquid crystal

In accordance with the invention, gradation display is performed for each picture element in capacitive display apparatuses such as EL display apparatus by means of pulse width modulation. In doing so, pulse duration of the voltage applied to one group of electrodes among the a plurality of electrodes arranged in matrix is so set as to span over two scanning periods, during which another group of electrodes which are grouped into pairs each of two adjacent lines are scanned successively. This reduces the number of drive voltage charge and discharge cycles. Consequently power consumption of the display apparatus of PWM system can be controlled to a low level.

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Nara, Japan

Yoshiyuki Kokuhata