Abstract: A current measurement circuit measures a current flowing through a drive transistor when a plurality of measurement voltages are written to a pixel circuit in a switching manner, and a current flowing through an organic EL element when another plurality of measurement voltages are written to the pixel circuit in a switching manner. A correction unit obtains a threshold voltage and a gain of the drive transistor and the organic EL element with respect to each pixel circuit based on a measured current, determines in which operation region the drive transistor operates between a saturation region and a triode region with respect to each pixel circuit based on the video signal, and corrects the video signal in accordance with the operation region of the drive transistor. Since the drive transistor operates both in the saturation region and the triode region, it is possible to reduce a power supply voltage and reduce power consumption of a display device.

Abstract: The purpose of the present invention is to suppress the fluctuation of a data line voltage that occurs when an analog voltage signal is sampled and held in a data line in a display device provided with a current-driven display element. Transistors (SWr, SWG, SWb) of each demultiplexer (252) are successively switched on, for each predetermined period, in a selection period of a write control line (SW_LR(i)). In a period when the transistor (SWr) is switched on, an analog video signal (Dj) from a data voltage output unit circuit (211d) is applied to a data line (SLrj) and a pixel circuit (50r). When the transistor SWr is then switched off, the voltage held by the data line (SLrj) decreases below the voltage of the analog video signal (Dj) due to a parasitic capacitance (Cssdr). However, the voltage of a voltage fluctuation compensation line (G3_Cnt (i)) changes from a low level to a high level within the selection period.

Abstract: An object of the present invention is to implement a display device capable of compensating for degradation of circuit elements without causing a grayscale failure. Based on the results of detection of characteristics of drive transistors and organic EL elements, a control circuit (20) finds magnitudes of threshold shifts of the drive transistors and the organic EL elements. A power supply voltage control unit (201) sets a value of a low-level power supply voltage (ELVSS) 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 (201) adjusts a value of a high-level power supply voltage (ELVDD), depending on magnitudes of mobilities obtained by detection of characteristics of the drive transistors.

Abstract: A current sensor outputs an output voltage in accordance with a magnitude of a current to be measured. The current sensor includes a conductor through which a current flows, magnetic sensors, and correctors. The magnetic sensors detect a strength of a magnetic field generated by the current and output an output voltage corresponding to the strength of the magnetic field as the output voltage from the current sensor. The correctors each correct fluctuations in magneto-electric conversion gains of the magnetic sensors caused by a change in an ambient temperature and fluctuations in the output voltages from the magnetic sensors caused by deformation of the conductor due to a change in the ambient temperature.

Abstract: In a current measurement period of a pixel circuit (20), a measurement voltage is applied to a non-inverting input terminal of an operational amplifier (31), switches (35, 36) turn on, and a switch (37) turns off. Next, the switch (36) turns off, and a capacitor (32) is charged with charge of a current flowing through the pixel circuit (20). Next, the switch (35) turns off, the switch (37) turns on, a constant current flows through a current source (33), and a voltage of a second terminal (terminal connected to an output terminal of the operational amplifier (31)) of the capacitor (32) decreases. A voltage comparator (42) and a counter (43) measure the current flowing through the pixel circuit (20) by measuring time until a voltage of the second terminal of the capacitor reaches a voltage Vcomp. A video signal VS1 is corrected based on a current measurement result.

Abstract: An organic EL panel 10 is a bendable display panel including a plurality of pixel circuits 60 each having a light emitting element and a drive element. A data line drive circuit 15 performs, by driving data lines, an operation of writing a voltage to a control terminal of the drive element and an operation of measuring a current flowing through the drive element for the pixel circuits 60 selected by a scanning line drive circuit 14. A bending detection unit 90 detects a bending state of the organic EL panel 10 based on a measurement result of the current flowing through the drive element. A correction unit 80 corrects a video signal VS1 based on the detected bending state. With this, the bending state of a screen is detected and a change in brightness or color when the screen is bent is prevented.

Abstract: In each of pixel circuits in an organic EL display device configured to display color images in a field sequential method, a drive transistor is connected to first to third organic EL elements configured to emit red light, green light, and blue light through first to third light emission control transistors. A connection point between the drive transistor and the light emission control transistors is connected to a data line through a monitor control transistors. A data-side driving circuit is provided with a data voltage output unit circuit and a current measurement unit circuit for each of data lines. The data-side driving circuit is configured to be able to switch between the unit circuits to connect either one of the unit circuits to the data line.

Abstract: An organic EL display device includes: a pixel circuit drive unit configured to drive pixel circuits while performing a property measuring process in which a property of circuit elements is measured; a parameter table configured to store parameter values derived from monitoring data obtained in the property measuring process; a compensation computation unit configured to correct externally provided image data based on the parameter values stored in the parameter table, so as to generate a digital video signal to be fed to the pixel circuits; a temperature sensor configured to sense temperature; and a monitoring control section configured to control an execution frequency of the property measuring process in accordance with the sensed temperature. The monitoring control section increases the execution frequency of the property measuring process with an increase in the sensed temperature.

Abstract: An object of the present invention is to implement a display device capable of compensating for degradation of circuit elements without causing a grayscale failure. Based on the results of detection of characteristics of drive transistors and organic EL elements, a control circuit (20) finds magnitudes of threshold shifts of the drive transistors and the organic EL elements. A power supply voltage control unit (201) sets a value of a low-level power supply voltage (ELVSS) 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 (201) adjusts a value of a high-level power supply voltage (ELVDD), depending on magnitudes of mobilities obtained by detection of characteristics of the drive transistors.

Abstract: In a current measurement period set in a pause period, a display device of the present invention applies measurement voltages to data lines (S1 to Sm) and measures currents outputted to monitoring lines (M1 to Mm) from m pixel circuits (18), and then applies data voltages generated corresponding to video signals to the data lines (S1 to Sm).

Abstract: In a current measurement period set in a pause period, a display device of the present invention applies measurement voltages to data lines (S1 to Sm) and measures currents outputted to monitoring lines (M1 to Mm) from m pixel circuits (18), and then applies data voltages generated corresponding to video signals to the data lines (S1 to Sm).

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: In a data line drive/current measurement circuit, m measurement units are disposed in a plurality of semiconductor chips such that the m measurement units are distributed among the plurality of semiconductor chips. A display apparatus includes transistors such that one transistor is provided for two adjacent semiconductor chips. Inter-chip correction data indicating a variation among the semiconductor chips in terms of characteristics of elements in the measurement units is determined based on a result of a current measurement performed for the same transistor using measurement units disposed in different semiconductor chips. The inter-chip correction data is stored in a storage unit and is used in correcting an image signal. The inter-chip correction data may be determined based on a result of measuring a current flowing through a common cathode of organic EL elements for each semiconductor chip.

Abstract: The purpose of the present invention is to suppress the fluctuation of a data line voltage that occurs when an analog voltage signal is sampled and held in a data line in a display device provided with a current-driven display element. Transistors (SWr, SWG, SWb) of each demultiplexer (252) are successively switched on, for each predetermined period, in a selection period of a write control line (SW_LR(i)). In a period when the transistor (SWr) is switched on, an analog video signal (Dj) from a data voltage output unit circuit (211d) is applied to a data line (SLrj) and a pixel circuit (50r). When the transistor SWr is then switched off, the voltage held by the data line (SLrj) decreases below the voltage of the analog video signal (Dj) due to a parasitic capacitance (Cssdr). However, the voltage of a voltage fluctuation compensation line (G3_Cnt (i)) changes from a low level to a high level within the selection period.

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 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: A display device that is configured to include two independent shift registers and is capable of performing a monitoring process without causing the degradation of display quality or the occurrence of abnormal operation is implemented. In a display device including: a writing control shift register composed of a plurality of first unit circuits (30) each including a first boost circuit (320) and a first output node reset circuit (330); and a monitoring control shift register composed of a plurality of second unit circuits (40) each including a second boost circuit (420) and a second output node reset circuit (430), current drive capability of the first boost circuit (320) is higher than current drive capability of the second boost circuit (420), and current drive capability of the second output node reset circuit (430) is higher than current drive capability of the first output node reset circuit (330).

Abstract: In a current measurement period of a pixel circuit (20), a measurement voltage is applied to a non-inverting input terminal of an operational amplifier (31), switches (35, 36) turn on, and a switch (37) turns off. Next, the switch (36) turns off, and a capacitor (32) is charged with charge of a current flowing through the pixel circuit (20). Next, the switch (35) turns off, the switch (37) turns on, a constant current flows through a current source (33), and a voltage of a second terminal (terminal connected to an output terminal of the operational amplifier (31)) of the capacitor (32) decreases. A voltage comparator (42) and a counter (43) measure the current flowing through the pixel circuit (20) by measuring time until a voltage of the second terminal of the capacitor reaches a voltage Vcomp. A video signal VS1 is corrected based on a current measurement result.

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: A current measurement circuit measures a current flowing through a drive transistor when a plurality of measurement voltages are written to a pixel circuit in a switching manner, and a current flowing through an organic EL element when another plurality of measurement voltages are written to the pixel circuit in a switching manner. A correction unit obtains a threshold voltage and a gain of the drive transistor and the organic EL element with respect to each pixel circuit based on a measured current, determines in which operation region the drive transistor operates between a saturation region and a triode region with respect to each pixel circuit based on the video signal, and corrects the video signal in accordance with the operation region of the drive transistor. Since the drive transistor operates both in the saturation region and the triode region, it is possible to reduce a power supply voltage and reduce power consumption of a display device.