Sharp Kabushiki Kaisha Corporation

The Secretary of State for Defence in Her Britannic Majesty's Government

Other

Takaji Numao

Akira Tagawa

Hirofumi Katsuse

Seiichi Gohshi

Takashi Mine

Kazunari Tomizawa

Mitsuhiro Koden

Makoto Shiomi

Mikio Katayama

John Clifford Jones

Tokihiko Shinomiya

Naofumi Kondo

Kazuhiko Tamai

Keisaku Nonomura

Michiyuki Sugino

Kenichi Nakagawa

Hitoshi Takeda

Alistair Graham

Masayuki Katakami

Hiroshi Gouda

An image processing system for processing a target pixel to be processed, which target pixel corresponds to inputted image data, a plurality of pixels including the target pixel being arranged in a matrix manner, includes an NR circuit (). The NR circuit () includes a signal processing process circuit () for carrying out subtraction or addition, with respect to a pixel value Aij of the target pixel, of a value equivalent to a noise quantity Er calculated in advance, in a case where the pixel value Aij of the target pixel is larger or smaller, respectively, than a first couple of estimated values Bij and Cij for the pixel value Aij of the target pixel, the first couple of estimated values Bij and Cij being estimated from pixel values of respective pixels adjacent to the target pixel, centered at the target pixel, in a temporal axis or in a spatial axis. It is therefore possible to provide an image processing system which further reduces noise and is less likely to blur a video as compared with a conventional noise reduction process.

Image processing system and display device for carrying out subtraction or addition of a pixel value of a target pixel in accordance with a value equivalent to a noise quantity

A signal processing device () includes noise reduction units (), cascade-connected to each other, each of which includes: a signal selection section () for selecting a representative value from sampled signals obtained from an input signal by sampling a target signal and signals which are away from the target signal by given intervals; a voltage determination section () for determining which of a determined representative value and a voltage of the target signal is larger; and a signal output section () for increasing or decreasing the voltage of the target signal depending on a result of the determining and outputs the target signal as the output signal. A combination of intervals between the target signal and the signals excluding the target signal vary from noise reduction unit () to noise reduction unit (). A noise reduction unit on a more upstream side has a larger maximum value of the intervals.

Signal processing device, integrated circuit, control program, and computer readable recording medium

A liquid crystal display device () of the present invention includes an NR circuit () for carrying out a signal processing process in which a predetermined noise amount is added to or subtracted from data of a target pixel in accordance with a result of a comparison of signal levels between the target pixel and at least two surrounding pixels which are beside the target pixel, the NR circuit () adding or subtracting the predetermined noise amount to or from data of respective pixels adjacent to each other temporally or positionally in respective different signal processing processes. This allows providing a liquid crystal display device having a noise reduction effect. It is thus possible to provide a liquid crystal display device enabling less blur of an image after a noise reduction process.

Image processing system and display device

During first period, TFTs:andare set in ON and OFF states, respectively. Potential Va is fed into a source line Sj so that potential of pixel electrode is Va. During second period, the TFTs:andare set in the OFF and ON states, respectively. The potential Va is continuously fed into the source line Sj. This sets potential of node to Va, thereby changing the potential of the pixel electrode. During third period, the TFTs:andare set in the OFF state. This realizes a display device where high cost factors and power consumption increase are suppressed, and the effective value of voltage expressed by difference between potential applied to a driving potential input terminal and reference potential can have variance larger than amplitude of signal voltage fed into a data signal line, the variance corresponding to variation in the signal voltage.

Display device

A display device in accordance with the present invention includes: a gate driver for carrying out display scanning on pixels sequentially in a first direction of a TFT liquid crystal panel so as to set pixels to display states thereof according to information to be displayed by the pixels in the TFT liquid crystal panel, the pixels being arranged in two dimensions and being individually controllable in terms of the display state through illumination; and a backlight unit for illuminating the individual pixels with intensity of light which increases and subsequently decreases in synchronism with the display scanning carried out by the gate driver, but only after the display scanning. The arrangement enables the backlight flashing period to be determined independently from a TFT panel scanning period or response time of liquid crystal, ensures an extended operating time of a TFT panel, effects a display period equal to, or longer than, the black blanking type, and achieves higher contrast than the black blanking type.

Display device and light source

One embodiment of the present invention discloses a display device which can use a display element having a relatively large difference between a minimum gradation voltage and a maximum gradation voltage. A first selection period and a second selection period are included in a period (a scanning signal line selection period) in which each gate wiring is selected. In the first selection period, a first selection voltage for allowing every TFT included in a line, which is an object to be selected, to be in an ON state is applied to the gate wiring of the line which is the object to be selected. In a period between the first selection period and the second selection period, a non selection voltage is applied to the gate wiring which is the object to be selected and the voltage of an auxiliary capacity wiring corresponding to the gate wiring which is the object to be selected is changed. In the second selection period, a second selection voltage for allowing a part of the TFTs included in the line, which is the object to be selected, to be in an ON state is applied to the gate wiring which is the object to be selected.

Display device, it's driving circuit, and driving method

In one embodiment, a display device of the present invention includes capacitors provided between a gate and a source of a driver TFT. During a select period, a voltage is fed to the gate terminal of the driver TFT, and a voltage is fed to the source terminal of the driver TFT. Thereafter, during a threshold correction period, the gate voltage of the driver TFT is retained to make the source voltage of the driver TFT equal to Vda&#x2212;Vth (&#x3c;Vcom). Subsequently, the gate voltage of the driver TFT is changed to control a current flowing between the drain and the source of the driver TFT.

A switching transistoris provided between a gate terminal of a driving TFTand a drain terminal thereof. A first capacitoris provided between the gate terminal of the driving TFTand a source terminal thereof. The current control terminal of the driving TFTis connected to a first terminal of a second capacitor. A second terminal of the second capacitoris connected to the drain terminal of the driving TFTvia a switching transistor, and to a predetermined voltage line Va via a switching transistor. This allows restraint of variation of a current flowing, during a non-selection period, through a current driving light emitting element of a display apparatus, the current variation being caused by threshold voltage variation and mobility variation of the driving TFT. A specific example of the display apparatus including such a current driving light emitting element is an organic EL display apparatus.

Display apparatus and driving method thereof

When the transistor Qis OFF, a predetermined potential is supplied to a potential wire Ui such that a switching transistor Qbecomes ON. This changes a gate potential of a driving transistor Qfrom an ON potential to a threshold potential. Thereafter, the transistor Qis turned OFF, with the result that the potential of the potential wire Ui is changed (in cases where the transistor Qis a p-type transistor, the potential is decreased). With this, the transistor Qallows a current to constantly flows therethrough, irrespective of the threshold potential. This shortens time for setting an output current of the driving TFT for driving a current driving type display element.

Display apparatus

A display device includes: a gate driver for carrying out display scanning on pixels sequentially in a first direction of a TFT liquid crystal panel so as to set pixels to display states thereof according to information to be displayed by the pixels in the TFT liquid crystal panel. The pixels being arranged in two dimensions and being individually controllable in terms of the display state through illumination. There is a backlight, unit for illuminating the individual pixels with intensity of light which increases and subsequently decreases in synchronism with the display scanning carried out by the gate driver, but only after the display scanning. The arrangement enables the backlight flashing period to be determined independently from a TFT panel scanning period or response time of liquid crystal, ensures an extended operating time of a TFT panel, effects a display period equal to, or longer than, the black blanking type, and achieves higher contrast than the black blanking type.

A display device in accordance with the present invention changes to Vc the voltage of a terminal of a capacitor Cthe other terminal of which is connected to the gate of a driver TFT Q. Thus, a desired voltage Vda is fed from a source line Sj to the drain of the driver TFT Qso as to adjust the threshold voltage Vth of the driver TFT Q. The device then changes the voltage of the terminal of the capacitor Cto Va to render the gate voltage of the driver TFT QVda-Vth-Vc+Va. A power supply voltage Vp is fed from the source of the driver TFT Q

Display device and driving method thereof

A display device which makes it possible to shorten a selection period per pixel while compensating variations in a threshold voltage of the driving transistor, and a method for driving the same are achieved. In a pixel circuit Aij, a potential wire Ui is set to a potential Vcc, a voltage of a gate wire Gi becomes Low, a voltage of a control wire Ri becomes High, and a voltage of a control wire Pi becomes High, so that a gate terminal of a driving TFT: Qhas a potential of a data wire Dj. Moreover, a voltage of the gate wire Gi becomes High so as to compensate a threshold voltage of the driving TFT: QThereafter, a voltage of the control wire Pi becomes Low, and the potential wire Ui is set to a potential Vc, so that a voltage of a capacitor Ci.e., a gate-source voltage of the driving TFT is changed. This causes a voltage of the control wire Ri to be Low, so that a driving current is flown into an organic EL: EL

Display device and method for driving the same

A current driver circuit in a driver circuit generates, and maintains, a state where a drive current for an electro-optic device flows through a current output TFT and a capacitor, using a constant current output from a single constant current source during a non-drive controllable period for the pixel. The driver circuit performs the previous operation on each pixel. The current driver circuit then generates the drive current in the maintained circuit state and passes the drive current through a source line to the pixel which is in a drive controllable period by means of voltage state of the gate line, so as to control the driving of the pixel. Thus, in the pixel receiving the drive current, the drive current flows through the electro-optic device to effect a display. The current driver circuit for the electro-optic device is capable of inhibiting the current value from varying from one source line to another, while permitting construction based on a low temperature polysilicon TFT or CG silicon TFT.

Display

When time division gradation display is carried out by setting a display state of an electro-optic element capable of R-gradation display A times in one frame period, the present invention determines the weights of the bit data to be such as 2:2:2:2: . . . , in which a conventional ratio regulation of 2:2:2:2: . . . i.e., 1:2:4:8: . . . is changed by at least one part at or later the third bit so as to satisfy the relation of B&#x3c;Rwhere B expresses the number of display gradations. With this arrangement, it is possible to realize the time division gradation display with a desirable number of scanning lines and the desirable bit weight ratio, without significantly changing the actually-recognized image. On this account, the range of the electro-optic device, capable of setting each stage of outputs in the frame period to be a desirable value, can be enlarged with respect to a matrix display device using the time division gradation display.

Driving device for electro-optic device, display device using the driving device, driving method thereof, and weight determination method thereof

Each pixel of an EL display panel includes a diode element, an organic EL element, and a capacitor. The cathode of the diode element, the anode of the organic EL element, and one of the electrodes of the capacitor are electrically connected to one another at a common terminal. The anode of the diode element is connected to a signal electrode. The other electrode of the capacitor is connected to a scanning electrode. The cathode of the organic EL element is connected to the scanning electrode. A forward direction of the diode element and a forward direction of the organic EL element coincide. The voltage between the scanning electrodes is controlled to control the current flowing through the organic EL element. As a result, it is possible to provide an emitter having stable luminance with improved efficiency, and an emitting device and a display panel employing such an emitter.

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Nara, Japan

Takaji Numao