Patent classifications
G09G3/3258
Pixel Circuit and Display Device Including the Same
A pixel circuit and a display device including the same are disclosed. The pixel circuit includes a driving element including a first electrode connected to a first node to which a pixel driving voltage is applied, a gate electrode connected to a second node, and a second electrode connected to a third node, and configured to supply an electric current to a light emitting element; a first switch element discharging the second node; and a second switch element configured to supply a data voltage to the second node. The light emitting element and the first switch element are commonly connected to a VSS node to which a low-potential power supply voltage is applied.
Method and device for detecting display substrate
The present disclosure provides a method for detecting a display substrate and a device for detecting a display substrate. The method includes: exciting a threshold voltage of a driving transistor in each pixel driving circuit in the display substrate, so that the threshold voltage of the driving transistor with a shifted threshold voltage is further shifted; inputting a detection signal to each pixel driving circuit in the display substrate, where the detection signal is a signal enabling the pixel driving circuit to operate normally; and judging whether the display substrate is normal or not according to the voltage output by each pixel driving circuit.
Display device and driving method thereof
A driving method of a display device including a power source which supplies a power voltage to a power base line, and pixels connected to power branch lines commonly connected to the power base line, includes calculating a first scale factor based on input grayscales received during a first frame period; calculating first output grayscales by applying the first scale factor to first input grayscales received during a second frame period, where the second frame period is a frame period immediately next to the first frame period; displaying an image by at least a part of the pixels based on the first output grayscales; and providing a first current limiting signal to the power source and calculating a second scale factor smaller than the first scale factor when a current of the power base line exceeds a reference value.
SYSTEM AND METHODS FOR EXTRACTION OF THRESHOLD AND MOBILITY PARAMETERS IN AMOLED DISPLAYS
Disclosed is a system and method to improve the extraction of transistor and OLED parameters in an AMOLED display for compensation of programming voltages to improve image quality. A pixel circuit includes an organic light emitting device, a drive device to provide a programmable drive current to the light emitting device, a programming input to provide the programming signal, and a storage device to store the programming signal. A charge-pump amplifier has a current input and a voltage output. The charge-pump amplifier includes an operational amplifier in negative feedback configuration. The feedback is provided by a capacitor connected between the output and the inverting input of the operational amplifier. A common-mode voltage source drives the non-inverting input of the operational amplifier. An electronic switch is coupled across the capacitor to reset the capacitor. A switch module including the input is coupled to the output of the pixel circuit and an output is coupled to the input of the charge-pump amplifier. The switch module includes a set of electronic switches that may be controlled by external control signals to steer current in and out of the pixel circuit and provide a discharge path between the pixel circuit and the charge-pump amplifier and isolating the charge-pump amplifier from the pixel circuit. A controller is coupled to the pixel circuit, charge-pump amplifier and the switch module. The controller controls input signals to the pixel circuit, charge-pump amplifier and switch module in a predetermined sequence to produce an output voltage value which is a function of a parameter of the pixel circuit. The sequence includes providing a program voltage to the programming input to either pre-charge an internal capacitance of the pixel circuit to a charge level and transfer the charge to the charge-pump amplifier via the switch module to generate the output voltage value or provide a current from the pixel circuit to the charge-pump amplifier via the switch module to produce the output voltage value by integration over a certain period of time.
SYSTEM AND METHODS FOR EXTRACTION OF THRESHOLD AND MOBILITY PARAMETERS IN AMOLED DISPLAYS
Disclosed is a system and method to improve the extraction of transistor and OLED parameters in an AMOLED display for compensation of programming voltages to improve image quality. A pixel circuit includes an organic light emitting device, a drive device to provide a programmable drive current to the light emitting device, a programming input to provide the programming signal, and a storage device to store the programming signal. A charge-pump amplifier has a current input and a voltage output. The charge-pump amplifier includes an operational amplifier in negative feedback configuration. The feedback is provided by a capacitor connected between the output and the inverting input of the operational amplifier. A common-mode voltage source drives the non-inverting input of the operational amplifier. An electronic switch is coupled across the capacitor to reset the capacitor. A switch module including the input is coupled to the output of the pixel circuit and an output is coupled to the input of the charge-pump amplifier. The switch module includes a set of electronic switches that may be controlled by external control signals to steer current in and out of the pixel circuit and provide a discharge path between the pixel circuit and the charge-pump amplifier and isolating the charge-pump amplifier from the pixel circuit. A controller is coupled to the pixel circuit, charge-pump amplifier and the switch module. The controller controls input signals to the pixel circuit, charge-pump amplifier and switch module in a predetermined sequence to produce an output voltage value which is a function of a parameter of the pixel circuit. The sequence includes providing a program voltage to the programming input to either pre-charge an internal capacitance of the pixel circuit to a charge level and transfer the charge to the charge-pump amplifier via the switch module to generate the output voltage value or provide a current from the pixel circuit to the charge-pump amplifier via the switch module to produce the output voltage value by integration over a certain period of time.
ORGANIC LIGHT EMITTING DIODE DISPLAY
An organic light emitting diode display with improved aperture ratio includes: a substrate; first and second pixels disposed in a first row of the substrate and third and fourth pixels disposed in a second row adjacent to the first row and respectively disposed in the same columns as the first and second pixels; a scan line and a previous scan line applying a scan signal and a previous scan signal, respectively, to the pixel units; a data line and a driving voltage line applying a data signal and a driving voltage, respectively, to the pixel units; and a common initialization voltage line disposed between the first and second pixels and between the third and fourth pixels, commonly connected to the pixel units, and applying an initialization voltage. One common initialization contact hole connected to all pixels units and one initialization voltage line connected to the common initialization contact hole are surrounded by the pixel units.
ORGANIC LIGHT EMITTING DIODE DISPLAY
An organic light emitting diode display with improved aperture ratio includes: a substrate; first and second pixels disposed in a first row of the substrate and third and fourth pixels disposed in a second row adjacent to the first row and respectively disposed in the same columns as the first and second pixels; a scan line and a previous scan line applying a scan signal and a previous scan signal, respectively, to the pixel units; a data line and a driving voltage line applying a data signal and a driving voltage, respectively, to the pixel units; and a common initialization voltage line disposed between the first and second pixels and between the third and fourth pixels, commonly connected to the pixel units, and applying an initialization voltage. One common initialization contact hole connected to all pixels units and one initialization voltage line connected to the common initialization contact hole are surrounded by the pixel units.
ELECTROLUMINESCENT DISPLAY
An EL display includes a flexible board including: a plurality of connection terminals arranged at one side for connection with panel lines formed on a panel board; terminal connection lines for connecting points inside the flexible board with the connection terminals; serial connection lines for connecting between two or more of the connection terminals. On the flexible board: driver output terminals of each of gate driver ICs are connected to terminal connection lines; driver input terminals of the gate driver IC are connected to either terminal connection lines or the serial connection lines; and control terminals for performing logic setting of the gate driver IC are each arranged between connection terminals and driver input terminals to which the serial connection lines are connected. As a result, the number of control lines to be formed on the flexible board in serial connection is reduced.
ELECTROLUMINESCENT DISPLAY
An EL display includes a flexible board including: a plurality of connection terminals arranged at one side for connection with panel lines formed on a panel board; terminal connection lines for connecting points inside the flexible board with the connection terminals; serial connection lines for connecting between two or more of the connection terminals. On the flexible board: driver output terminals of each of gate driver ICs are connected to terminal connection lines; driver input terminals of the gate driver IC are connected to either terminal connection lines or the serial connection lines; and control terminals for performing logic setting of the gate driver IC are each arranged between connection terminals and driver input terminals to which the serial connection lines are connected. As a result, the number of control lines to be formed on the flexible board in serial connection is reduced.
PIXEL CIRCUITS FOR AMOLED DISPLAYS
A system is provided for controlling an array of pixels in a display in which each pixel includes a light-emitting device and a reference voltage source that controllably supplies a reference voltage having a magnitude that turns off the light-emitting device. While the reference voltage is coupled to a drive transistor, a control voltage is supplied to the gate of the drive transistor to cause the drive transistor to transfer to a node common to the drive transistor and the light-emitting device, a voltage that is a function of the threshold voltage and mobility of the drive transistor. During an emission cycle, the current conveyed through the light emitting device via the drive transistor is controlled by a voltage stored in the storage capacitor, which is a function of the threshold voltage and mobility of the drive transistor so that the current supplied to the light-emitting device remains stable.