1. Field of the Invention
The present invention relates to an organic light emitting display (OLED), and more particularly, to an OLED that makes use of demultiplexers to decrease the number of output lines of data drivers and display an image having uniform luminance.
2. Description of the Related Art
In recent years, a variety of flat panel displays (FPDs) with small weight and volume have been developed to overcome the drawbacks of a cathode ray tube (CRT). The FPDs can be categorized into a liquid crystal display (LCD), a field emission display (FED), a plasma display panel (PDP), an organic light emitting display (OLED), and the like.
An OLED includes an organic light emitting diode, which is a self-emissive display device that emits light through the recombination of electrons supplied from a cathode and holes supplied from an anode. The OLED has a high response speed of about 1 μs and consumes low power. The OLED includes a plurality of pixels, each of which supplies a driving current corresponding to a data signal to the organic light emitting diode using a driving thin film transistor (TFT) so that the organic light emitting diode emits light to display a predetermined image.
FIG. 1 is a block diagram of a conventional OLED.
Referring to FIG. 1, the conventional OLED includes a display panel 10, a scan driver 20, a data driver 30, and a timing controller 40.
The display panel 10 includes a plurality of pixels P11-Pnm, which are disposed in regions where a plurality of scan lines and emission control lines S1-Sn and E1-En intersect a plurality of data lines D1-Dm. Each of the pixels P11-Pnm receives a first power supply Vdd and a second power supply Vss from external power supplies and emits light corresponding to a received data signal to display an image. Also, the pixels P11-Pnm emit light for a time that is controlled according to a signal supplied through the emission control lines E1-En, respectively.
The scan driver 20 generates a scan signal in response to a scan control signal Sg received from the timing controller 40 and sequentially transmits the generated scan signal to the plurality of scan lines S1-Sn to select the pixels P11-Pnm. Also, the scan driver 20 generates an emission control signal in response to the scan control signal Sg and sequentially transmits the generated emission control signal to the plurality of emission control lines E1-En to control the emission.
The data driver 30 receives red (R), green (G), and blue (B) data from the timing controller 40, generates data signals in response to a data control signal Sd, and transmits the generated data signals to the plurality of data lines D1-Dm. In this case, the data driver 30 transmits data signals corresponding to one horizontal line for each horizontal period to the plurality of data lines D1-Dm.
The timing controller 40 generates data control signals Sd and scan control signals Sg corresponding to R, G, and B data supplied from an external graphic controller (not shown) and horizontal and vertical synchronous signals Hsync and Vsync. The data control signals Sd and the scan control signals Sg generated by the timing controller 40 are supplied to the data driver 30 and the scan driver 20, respectively.
In the conventional OLED having the above-described construction, the respective pixels P11-Pnm are located in the regions where the scan lines and the emission control lines S1-Sn and E1-En intersect the data lines D1-Dm. Here, the data driver 30 includes m output lines such that it transmits data signals to each of the m data lines D1-Dm. In other words, the data driver 30 should include the output lines in a number equal to the number of the data lines D1-Dm. Accordingly, the data driver 30 should include a plurality of data integrated circuits (ICs) to install the m output lines, thus elevating the cost of production. In particular, as the display panel 10 increases in resolution and size, the data driver 30 should include more data ICs. Thus, the cost of production further increases.