Abstract: A pixel circuit is capable of maintaining a display quality even in cases where an input transistor has a low mobility, or where it is impossible to take a sufficient selection period for each scanning line. A pixel circuit includes an organic EL element (OLED), transistors, and a capacitor. A drive transistor has its drain terminal connected to a HIGH level power supply line, and has its source terminal connected to an anode terminal of the OLED. The first input transistor has its gate terminal connected to a scanning line Si, and is disposed between a data line Dj and the gate terminal of the drive transistor. The second input transistor has its gate terminal connected to a scanning line (Si?1) in the (i?1)th row, and is disposed between a data line and the gate terminal of the drive transistor. The capacitor is disposed between the gate terminal and the source terminal of the drive transistor.

Abstract: Based on the results of detection of characteristics of drive transistors and organic EL elements, a control circuit finds magnitudes of threshold shifts of the drive transistors and the organic EL elements. A power supply voltage control unit sets a value of a low-level power supply voltage to a value lower, by a voltage value corresponding to an average value of the magnitudes of the threshold shifts for all pixels, than a value at an initial point in time. Furthermore, the power supply voltage control unit adjusts a value of a high-level power supply voltage, depending on magnitudes of mobilities obtained by detection of characteristics of the drive transistors.

Abstract: A display device that can compensate for degradation of circuit elements while suppressing an increase in circuit size is implemented. A data signal line (S(j)) is not only used as a signal line that transfers a signal for allowing an organic EL element (OLED) in each pixel circuit (11) to emit light at a desired luminance, but also used as a signal line for characteristic detection. In addition, a switch (334) is provided between the data signal line (S(j)) and an internal data line (Sin(j)). In such a configuration, during an AD conversion period during which analog data obtained for characteristic detection is converted into digital data, the switch (334) is brought into an off state and a potential of the data signal line (S(j)) obtained immediately before the AD conversion period is supplied from through a predetermined control line (CL) to the data signal line (S(j)).

Abstract: A pixel circuit 10 includes four TFTs 11 to 14, a capacitor 15, and an organic EL element 16. Between a node A where the TFT 11 and the capacitor 15 are connected and a power supply line VPk, the TFT 14 is provided in place of a capacitor. The gate terminal of the TFT 14 is connected to a control line Ek. The TFT 14 is in an on state in a light emission period of the organic EL element 16. The power supply line VPk and control lines Ek and AZk are connected to the pixel circuits 10 in a plurality of rows. A display device simultaneously performs initialization to the pixel circuits 10 in the plurality of rows, simultaneously performs threshold detection to the pixel circuits 10 in the plurality of rows, sequentially writes data to the pixel circuits 10 row by row, and makes organic EL elements 16 included in the pixel circuits 10 in the plurality of rows emit light in the same period.

Abstract: A gate driver divides n scanning lines (G1 to Gn) into p blocks (BL1 to BLp), and provides for each block, a common selection period for selecting a whole or a part of k scanning lines included in the block, and a scanning period for sequentially selecting k scanning lines included in the block. A source driver (30) detects a characteristic of a driving transistor via a data line from a pixel circuit (11) corresponding to a scanning line that is being selected in the common selection period, and supplies to the data line a corrected data voltage that has been obtained by correcting the data voltage based on the detected characteristic of the driving transistor. Accordingly, there is provided a display device that can compensate for a characteristic variation of the driving transistor while solving a shortage of writing time.

Abstract: There is realized a display device capable of compensating for a deterioration of a circuit element while suppressing an increase of a circuit scale. One horizontal scanning period for a monitor row is composed of: a detection preparation period where preparation for detecting TFT characteristics and OLED characteristics is performed in the monitor row; a TFT characteristic detection period where current measurement for detecting the TFT characteristics is performed; an OLED characteristic detection period where current measurement for detecting the OLED characteristics is performed; and a light emission preparation period where preparation for allowing an organic EL element to emit light is performed in the monitor row. Data lines are used not only as signal lines that transfer a signal for allowing an organic EL element in each pixel circuit to emit light at desired brightness, but also as characteristic detecting signal lines.

Abstract: An organic EL display device includes an emission driver that has an ON-control transistor (T1e) and an OFF-control transistor (T2e) for each emission line. The ON-control transistor (T1e) in the i-th row has its gate terminal and drain terminal connected to the scanning line (Si+1) in the (i+1)th row whereas its source terminal is connected to the emission line (EMi) in the i-th row. The OFF-control transistor (T2e) in the i-th row has its gate terminal connected to the scanning line (Si?1) in the (i?1)th row, whereas its drain terminal is connected to the emission line (EMi) in the i-th row, and its source terminal is connected to a LOW level logic power supply line (VSS).

Abstract: A pixel circuit 10 is provided with TFTs 12 and 13 and an organic EL element 15 on a current path connecting a power supply line VPk and an electrode having a common potential Vcom. A display device 100 simultaneously performs initialization to pixel circuits 10 in a plurality of rows, simultaneously perform threshold detection to the pixel circuits 10 in the plurality of rows, sequentially writes data to the pixel circuits 10 row by row, and makes the organic EL elements 15 included in the pixel circuits 10 in the plurality of rows emit light in the same period. In a period from completion of threshold detection to start of light emission, the TFTs 11 and 13 are controlled to an off state, and a potential VP_C which is substantially equal to the common potential Vcom is applied to the power supply line VPk. Consequently, leak current flowing through the TFTs 12 and 13 can be suppressed, and the fluctuation in the node potential in the pixel circuit 10 in a standby period can be prevented.

Abstract: A picture-frame size of a display device including self light-emitting type display elements which are driven by a current is reduced over conventional devices. Transistors for controlling supply of a light-emission enable signal outputted from an emission driver to emission lines are provided between the emission driver and the emission lines. In such a configuration, based on selection signals provided to the transistors, one of the transistors is brought into an on state in each subframe, and each of the transistors is brought into an on state once during one frame period.

Abstract: A display device 100 includes a plurality of pixel circuits 10 arranged two-dimensionally; a plurality of power lines VPi provided for respective rows of the pixel circuits 10; p common power lines 9, each connected to two or more power lines VPi; and a power control circuit 4. Each pixel circuit 10 includes an organic EL element, a plurality of TFTs, and a capacitor and receives an initialization potential from a corresponding power line VPi. The power control circuit 4applies a power supply potential and the initialization potential to the p common power lines 9 in a switching manner. Accordingly, a display device is provided that has a configuration in which an initialization potential is provided to pixel circuits from power lines and that has a power control circuit small in circuit size.

Abstract: A monitor line electrically connectable with sources of drive transistors and positive electrodes of electro-optical elements is provided. A drive method includes a step of detecting the characteristics of a drive transistor, a step of detecting the characteristics of an electro-optical element, a step of storing characteristics data obtained on the basis of a result of the detection of the characteristics, as correction data for correcting a video signal, and a step of correcting the video signal on the basis of the correction data. Here, the length of a selection period is set to be equal for a monitored row and an unmonitored row. In addition, a potential given to the monitor line for the detection of the characteristics of the drive transistors and a potential given to the monitor line for the detection of the characteristics of the electro-optical elements are made different.

Abstract: A detection/correction output circuit of a data-line driving circuit is provided with a transimpedance circuit including an operational amplifier and a current-detection transistor to detect a driving current that has passed through a driving transistor in a pixel circuit. The output voltage of the operational amplifier is amplified by using resistance elements connected in series. Thereby, it is possible to compensate the threshold voltage of the driving transistor with high accuracy by establishing a prescribed relationship between the gain of the driving transistor and the gain of the current detection transistor (by matching both gains) even if there is a difference between both gains. The output voltage of the operational amplifier may be amplified using a non-inverting amplifier circuit.

Abstract: A drive circuit classifies frame periods as a drive period and a pause period, and applies a selection voltage to scanning lines in turn and applies voltages according to a video signal (a measurement voltage in the case of measurement targets) to data lines in turn during the drive period. During the pause period, the drive circuit applies the selection voltage to one scanning line corresponding to measurement target pixel circuits, and a measurement circuit measures drive currents outputted to the data lines from the measurement target pixel circuits. The drive circuit may set a write period and a measurement period in the pause period. During the write period, the drive circuit may apply the measurement voltage to the data lines. During the measurement period, the measurement circuit may measure drive currents outputted to the data lines from the measurement target pixel circuits.

Abstract: There is realized a display device capable of compensating for a deterioration of a circuit element while suppressing an increase of a circuit scale. One horizontal scanning period for a monitor row is composed of: a detection preparation period where preparation for detecting TFT characteristics and OLED characteristics is performed in the monitor row; a TFT characteristic detection period where current measurement for detecting the TFT characteristics is performed; an OLED characteristic detection period where current measurement for detecting the OLED characteristics is performed; and a light emission preparation period where preparation for allowing an organic EL element to emit light is performed in the monitor row. Data lines are used not only as signal lines that transfer a signal for allowing an organic EL element in each pixel circuit to emit light at desired brightness, but also as characteristic detecting signal lines.

Abstract: In a display device having a pixel circuit including an electro-optical element in which brightness is controlled by a current, and including a drive transistor for controlling a current to be supplied to the electro-optical element, a drive method therefor includes: a noise measurement step of measuring noise; characteristic detection steps of detecting characteristics of the drive transistor and the electro-optical element; a correction data update step of updating correction data, which serves for correcting a video signal, based on detection results in the characteristic detection step; and a video signal correction step of correcting the video signal based on the correction data. When noise with a standard value or more is detected in the noise measurement step, processing of the correction data update step is not performed.

Abstract: An embodiment of the present invention realizes a display device equipped with a self light-emitting type display element driven by a current, by using a pixel circuit having a configuration simpler than a conventional configuration. A pixel circuit includes a driving transistor (T1), an input transistor (T2), a capacitor (Cst), and three organic EL elements (OLED(R), OLED(G), and OLED(B)). Cathode terminals of the organic EL elements (OLED(R), OLED(G), and OLED(B)) are respectively connected to low-level power supply lines (ELVSS(R), ELVSS(G), and ELVSS(B)). In such a configuration, in each sub-frame, only a low-level power supply voltage (ELVSS) corresponding to the sub-frame is set to a relatively low level, and the other low-level power supply voltages (ELVSS) are set to relatively high levels.

Abstract: An organic EL display device includes a controller, a data driver, and a DRAM which provides a gain correction memory and a threshold voltage correction memory. The data driver sends, to the controller, first and second measurement data Im corresponding to the first and second measuring data voltages Vm, respectively. The controller compares ideal characteristic data IO(P) with the first and second measurement data Im, and updates threshold voltage correction data Vt and gain correction data B2R based on the comparison results. The controller corrects video data Vm based on the threshold voltage correction data Vt and the gain correction data B2R. Thereby, both threshold voltage compensation and gain compensation of a drive transistor are performed with respect to each pixel circuit, while display is performed.

Abstract: A detection output circuit provided in a source driver compares a voltage detected by a resistor and a voltage of a driving signal using comparators drives a transistor, a capacitor and an operational amplifier using a ramp signal so that they are maintained at voltages corresponding to a current flowing through a data line, and performs feedback control so that the potential of the data line is a desired potential. With this simple configuration, a data line circuit can be achieved that is capable of eliminating variation in driving transistor characteristics and the like, while performing current protection at high speed.

Abstract: A data line drive circuit provides a voltage according to a detection voltage and to a reference voltage, between the gate and source of a drive transistor in a pixel circuit, and detects a drive current having passed through the drive transistor and outputted external to the pixel circuit. A threshold voltage correction memory stores, for each pixel circuit, data representing a threshold voltage of the drive transistor. A display control circuit controls the reference voltage based on the data stored in the threshold voltage correction memory. By this, even if the threshold voltage of the drive transistor is changed, the drive current can be detected with a high accuracy. The threshold voltage correction memory may store, for each pixel circuit, data representing a difference between the threshold voltage of the drive transistor and the reference voltage.

Abstract: In a display device that has self light-emitting type display elements and that adopts time-division driving, power consumption is reduced over the conventional one. Each of emission lines is connected to the gate terminals of light-emission control transistors provided for organic EL elements of different light-emitting colors in three pixel circuits arranged side by side in an extension direction of scanning signal lines. When there is no change in image content throughout a period longer than or equal to a predetermined period during a time-division driving mode, an operating mode is switched to a pause driving mode. During the pause driving mode, emission drivers bring only first emission lines into a selected state, by which a still image with a ? resolution of an image displayed during the time-division driving mode is displayed on a display unit. During a pause period, peripheral drivers go into a pause state.