Actively driven organic light emitting display

Abstract

The invention provides a pixel circuit which improves the service life of the active matrix organic light-emitting device and comprises a first TFT, a second TFT, a third TFT, a first capacitor, a first organic light-emitting diode (OLED), a first gate scanning signal line, a second gate scanning signal line, a data signal line and a power signal line; the second gate scanning line of the current pixel line is composed of the first gate scanning line which is adjacent to the pixel line; the first TFT controls the power supply of the first OLED; the second TFT controls the time when the signal of the data line is written into the gate electrode node of the first TFT; the third TFT provides the discharge pathway which is from the first TFT gate electrode node to the first gate scanning signal line; the capacitor is used for storing charges and maintaining the voltage of the corresponding node; the organic light-emitting diode (OLED 310) is used for executing the light-emitting operation.

Description

technical field [0001] The invention relates to an active-driven organic light-emitting display device, belonging to the technical field of light-emitting display devices. Background technique [0002] Organic light emitting devices (OLEDs) can be driven by passive matrix (PM) or active matrix (AM). Compared with the PM driver, the AM driver has the advantages of larger displayed information capacity, lower power consumption, longer device life, and higher picture contrast. The PM drive is suitable for low-cost, simple display devices. [0003] Currently, there are basically two types of devices for AM-driven OLED fabricated on glass substrates, namely amorphous silicon (a-Si) thin film transistor (TFT) and low temperature polysilicon (LTPS) TFT. [0004] TFT devices will drift in device characteristics when they work in a DC voltage bias state for a long time. If some measures are not taken to deal with this drift, the device with characteristic drift will reduce the cur...

AI Technical Summary

Problems solved by technology

First of all, the circuit needs to introduce a negative voltage pulse signal for each pixel, so each row of pixels needs to add an additional signal wire, which reduces the pixel aperture ratio

Second, an external system drive circuit is required to provide a negative pulse generation circuit that cooperates with the scan drive signal, which increases the complexity of the system drive circuit

First, this design requires a top-emitting OLED device structure, and OLED fabrication is difficult to implement; second, compared with the basic AMOLED pixel, this circuit introduces multiple additional control signals, the wiring is complicated, and the complexity of the system driving circuit is greatly increased. ; Third, the number of devices in the pixel circuit is large, and the possibility of pixel failure in the process increases, which will lead to a decrease in product yield

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