Sharp Kabushiki Kaisha Corporation

Fujitsu Corporation

Au Optronics Corporation

Fujitsu Display Technologies Corporation

Sony Corporation

Yasutake Furukoshi

Katsuyoshi Hiraki

Tetsuya Kobayashi

Koichi Katagawa

Masanori Nishido

Satoshi Sekido

Toshihiro Suzuki

Tetsuya Hamada

Keiji Hayashi

Toshiaki Suzuki

Mari Sugawara

Fumiaki Yamada

Seiji Hayashimoto

Takae Ito

Masaki Miyahara

Toshimitsu Minemura

Hiroshi Nakano

Syouichi Fukutoku

Yoshihisa Narui

Kikuo Kotake

Kenko Honda

Toshiro Kojima

A drive control circuit includes a timing controller for detecting a change of a horizontal scanning frequency, a gate voltage generating circuit for generating two kinds of gate-on voltages Va and Vb (Va&#x3c;Vb), and a switch for outputting one of the gate-on voltages Va and Vb from the gate voltage generating circuit in accordance with an output of the timing controller. The timing controller includes a counter for counting the number of clocks for one horizontal period, and a comparator for comparing a count result with a threshold value. When the horizontal scanning frequency is in a normal state, the low gate-on voltage Va is outputted, and when the horizontal scanning frequency exceeds a predetermined threshold value, that is, the count value falls below a threshold value, the high gate-on voltage Vb is outputted.

Driving method and drive control circuit of liquid crystal display device, and liquid crystal display device including the same

A liquid crystal display device including an LCD panel modulating light transmissivities of plural pixels disposed in a matrix form on the basis of respective gradation data; an illumination device for irradiating light to the respective pixels while a ratio (duty ratio) of a lighting time in one frame period is changed; and a display data conversion part for calculating respective lightnesses and a lightness histogram from the respective gradation data, determining a threshold lightness from the lightness histogram on the basis of a previously determined ratio of pixels to be saturated in brightness, processing the respective gradation data on the basis of the threshold lightness to output them to the LCD panel, and outputting duty ratio data to change the duty ratio to the illumination device.

Illumination device and liquid crystal display device using the same

A liquid crystal display apparatus includes a plurality of pixels arranged in matrix form including respective transistors, a plurality of gate bus lines, each of which is coupled to gates of the transistors arranged in a corresponding single row, a plurality of data bus lines, each of which is coupled to one end of channels of the transistors arranged in a corresponding single column, a gate driver configured to successively drive the plurality of gate bus lines, and a timing control circuit configured to supply to the gate driver a timing signal indicative of a start of the successive driving of the plurality of gate bus lines and to mask the timing signal for a predetermined time period following the supplying of the timing signal.

Liquid crystal display apparatus and method of preventing malfunction in same

Disclosed herein is an information display apparatus for displaying an image received from an image supplying source on an image display section after carrying out a conversion process on the image in an image conversion section employed in the information display apparatus on demand. The information display apparatus may include a timing storage section, an image determination section, and an output-path switching section.

Image display apparatus and image display method

A liquid crystal display apparatus includes a liquid crystal panel, a driver configured to drive the liquid crystal panel, a control circuit configured to control the driver in response to a display data signal and control signal supplied from an exterior, and a check circuit configured to detect a change between frames in a detection-purpose signal that is included in at least one of the display data signal and control signal so as to output a check signal responsive to presence/absence of the change.

Liquid crystal display apparatus detecting a freeze state

The liquid crystal display device has a liquid crystal panel in which liquid crystal cells are disposed in intersection areas of scanning lines and data lines, respectively. A picture signal and a synchronous signal are supplied via external terminals, respectively. A timing controller generates a driving timing of the scanning lines and a driving timing of the data lines in response to the synchronous signal. Further, the timing controller varies at least one of the driving timing of the scanning lines and the driving timing of the data lines according to a cycle of the synchronous signal in order to keep a writing time of the picture signal supplied to the liquid crystal cells constant. Therefore, it is possible to keep the writing time constant even when the cycle of the synchronous signal varies, which can prevent the deterioration in display quality.

Liquid crystal display device

A plurality of gate driver boards are bonded to a first side of a TFT substrate, and a wiring board made of a flexible printed wiring board is bonded between the gate driver boards. Then, a wiring disposed on the wiring board provides connection between adjacent gate driver boards. In the same manner, a plurality of data driver boards are bonded to a second side of the TFT substrate, and a wiring board made of a flexible printed wiring board is bonded between the data driver boards. Then, a wiring disposed on the wiring board provides connection between adjacent data driver boards.

Polarity patterns (polarity pattern signal POL) are stored in a ROM in a polarity pattern controlling portion. Then, the polarity pattern is changed according to applications of a liquid crystal display panel. Since the polarity pattern is stored in the ROM, the polarity pattern can be changed without modification of a hardware. Also, two sets of polarity patterns or more are stored in the ROM, and then any one polarity pattern can be output according to the application. In addition, the polarity pattern signal POL and image signals RGB are compared with each other, and then the polarity pattern which is to be read from the ROM is switched according to the result.

Display panel driving method, display panel driver circuit, and liquid crystal display device

A drive control circuit supplies a gate voltage so that display quality is not degraded even in a case where a vertical scanning frequency or a horizontal scanning frequency is changed. The circuit includes a timing controller for detecting a change of a horizontal scanning frequency, a gate voltage generating circuit for generating two kinds of gate-on voltages Va and Vb (Va&#x3c;Vb), and a switch for outputting one of the gate-on voltages Va and Vb from the gate voltage generating circuit in accordance with an output of the timing controller. The timing controller includes a counter for counting the number of clocks for one horizontal period, and a comparator for comparing a count result with a threshold value. When the horizontal scanning frequency is in a normal state, the low gate-on voltage Va is outputted, and when the horizontal scanning frequency exceeds a predetermined threshold value, that is, the count value falls below a threshold value, the high gate-on voltage Vb is outputted.

A backlight driving circuit is controlled by a timing controller and executes on/off control of the backlights. The timing controller detects, using a synchronous signal, a change in a blank period which is of one frame period for display of one screen, during which the image signal is not transmitted. Upon detecting the change in the blank period, the timing controller adjusts the on-periods of the backlights in order to make the brightness of the backlights equal to one another. Consequently, the backlights have an equal brightness with one another in spite of the change in the blank period. This makes the lives of the backlights equal to one another. In a case where the plural backlights constitute a backlight unit, a reduction in life of the backlight unit is prevented. Further, it is also possible to prevent the brightness of the backlights from being differentiated even through a long-term use.

An illumination device is provided which can reduce a movement blur and a tailing phenomenon on a motion picture display while a drop in display brightness is suppressed, and which can suppress power consumption, can be made small and light, and can prolong the lifetime, and a liquid crystal display device using the same is provided. A light source control part of a control circuit synchronizes a latch pulse signal outputted from a gate driver control part to a gate driver, and outputs light emission control signals to respective light source power supply circuits. The respective light source power supply circuits change emission states of cold cathode fluorescent lamps to one of a first to a third emission states on the basis of the inputted light emission control signals, and illuminate an LCD panel from a rear surface of a display area. A first stage emission state is a non-lighting state, a second stage emission state is a maximum lighting state in which maximum lighting brightness is obtained, and a third emission state is an intermediate lighting state in which brightness of about one half of the second stage emission state is obtained.

A drive circuit device for a display device which drives a plurality of source bus lines provided on a display panel includes a driver unit that receives a clock signal, a data signal and a control signal, sequentially fetches the data signal, and generates drive signals for the source bus lines in accordance to the fetched data signal. The device further includes a gate unit that, after elapse of specified time from the reception of the driver unit, and at a timing when a rear-stage drive circuit device starts receiving, starts outputting of a propagation signal including at least one of the clock signal, data signal and control signal to the rear-stage drive circuit device. Consequently, the power consumption required for supplying these signals and the generated amount of electromagnetic waves resulting from the signal supply can be suppressed.

Drive circuit device for display device, and display device using the same

A timing controller for a liquid-crystal display panel includes a data enable signal detection circuit which detects a data enable signal applied to the timing controller, and a timing generating circuit which controls a display timing of image data to be displayed on the liquid-crystal display panel on the basis of the data enable signal detected by the data enable signal detection circuit.

Growing community of inventors

Kawasaki, Japan

Yasutake Furukoshi