CN102622962A

CN102622962A - Pixel circuit structure of active matrix-organic light-emitting diode (AMOLED)

Info

Publication number: CN102622962A
Application number: CN2012101060689A
Authority: CN
Inventors: 金正学; 文东星; 洪宣杓
Original assignee: Sichuan CCO Display Technology Co Ltd
Current assignee: Sichuan CCO Display Technology Co Ltd
Priority date: 2012-04-12
Filing date: 2012-04-12
Publication date: 2012-08-01

Abstract

The invention relates to a pixel circuit structure of an active matrix-organic light-emitting diode (AMOLED), which structurally comprises a switch transistor and a driving transistor. A grid electrode and a data end of the switch transistor are respectively connected with a scanning signal and a data signal, the output end of the switch transistor is connected with a grid electrode of the driving transistor, a power input end and a power output end of the driving transistor are respectively connected with a power supply and a light-emitting element, and a capacitor is connected between the grid electrode and the power input end of the driving transistor. The pixel circuit structure further comprises an initialization transistor, a grid electrode and an initialization end of the initialization transistor are simultaneously connected with initialization signals, and the output end of the initialization transistor is connected with the capacitor. The pixel circuit structure of the AMOLED can provide good display effect, is simple in structure and easy to maintain, and simultaneously has the advantages of being low in cost, stable in performance and the like.

Description

The image element circuit structure of AMOLED

Technical field

The present invention relates to circuit structure, is the image element circuit structure of AMOLED concretely.

Background technology

The basic image element circuit structure of AMOLED (active-matrix organic light emitting diode (AMOLED) panel) is as shown in Figure 1, has comprised 2 transistors and 1 basic AMOLED structure that electric capacity constitutes.On organic illuminating element D, connect driving transistors T2, luminous required electric current is provided.The magnitude of current of driving transistors T2 is controlled through the data voltage signal DATA of the source electrode input of switching transistor T1.Capacitor C is connected between source electrode and the grid of driving transistors T2 and is used for keeping within a certain period of time required voltage.The source electrode of switching transistor T1 is connected with data line.In the circuit of Fig. 1; Switching transistor T1 is according to the sweep signal SCAN that imports on its grid and conducting; Data voltage signal DATA is input to through switching transistor T1 on the grid of driving transistors T2, through driving the drain electrode with thin film transistor (TFT) T2, makes organic illuminating element D luminous again.

Traditional AMOLED image element circuit is not considered the display quality of display device, just in order to light organic diode.Along with the raising of user to the visual effect requirement; The AMOLED luminescent panel of volume production can provide high-quality display effect at present; But there are problems such as complex structure, price height in this luminescent panel, has therefore also limited popularizing and using of AMOLED luminescent panel.

Summary of the invention

To the problem of above-mentioned appearance, the invention provides the image element circuit structure of a kind of AMOLED, good display effect can be provided, and have characteristics such as simple in structure, with low cost.

The image element circuit structure of AMOLED of the present invention; Have switching transistor and driving transistors; The grid of switching transistor is connected sweep signal and data-signal respectively with data terminal, and the output terminal of switching transistor connects the grid of driving transistors, and the power input of driving transistors is connected power supply and light-emitting component respectively with output terminal; Between the grid of driving transistors and power input, be connected with electric capacity; Also include initialization transistor, the grid of initialization transistor is connected initializing signal simultaneously with the initialization end, and the output terminal of initialization transistor connects electric capacity.

Switching transistor is according to the sweep signal conducting, is the light-emitting component input data signal through driving transistors.But the residual charge before storing on the electric capacity between grid that is connected in driving transistors and the power input can exert an influence to the data-signal of output usually, reduces the display effect of light-emitting component.Therefore initialization transistor is set, passes through initializing signal earlier to the residual charge initialization on the electric capacity, behind specified magnitude of voltage initialization image element circuit, actuating switch transistor and driving transistors are exported the proper data signal again, guarantee display effect.All transistorized structures all are symmetrical in the circuit of the present invention, so each transistorized source electrode can exchange with drain electrode.

Preferred a kind of scheme is that described transistor is thin film transistor (TFT) (TFT).The effect of thin film transistor (TFT) is that to make each pixel on the AMOLED screen all be to be driven by the thin film transistor (TFT) that is integrated in thereafter, thereby makes that the AMOLED screen can be accomplished at a high speed, the demonstration of high brightness, high-contrast.Because each pixel of AMOLED screen all is to control by being integrated in from one's body TFT, is the active pixel point, therefore not only speed can greatly improve, and contrast also improved with brightness greatly, and while resolution has also reached high level.Thin film transistor (TFT) also has low pressure applications, low driving voltage and characteristic of low energy consumption simultaneously.

Further, described light-emitting component is a light emitting diode.

Test is learnt, the image element circuit structure of AMOLED of the present invention can provide good display effect, and simple in structure, is easy to safeguard, also has characteristics such as with low cost, stable performance simultaneously.

Below in conjunction with embodiment, foregoing of the present invention is remake further detailed description by the accompanying drawing illustrated embodiment.But should this be interpreted as that the scope of the above-mentioned theme of the present invention only limits to following instance.Do not breaking away under the above-mentioned technological thought situation of the present invention, various replacements or change according to ordinary skill knowledge and customary means are made all should comprise within the scope of the invention.

Description of drawings

Fig. 1 is a kind of synoptic diagram of the image element circuit structure of traditional AMOLED.

Fig. 2 is a kind of synoptic diagram of the image element circuit structure of AMOLED of the present invention.

Fig. 3 is the working timing figure of Fig. 2.

Embodiment

The image element circuit structure of AMOLED of the present invention as shown in Figure 2; Have switching transistor T1 and driving transistors T2; The grid of switching transistor T1 is connected sweep signal SCAN and data-signal DATA respectively with data terminal, and the output terminal of switching transistor T1 connects the grid of driving transistors T2, and the power input of driving transistors T2 and output terminal are connected the light-emitting component D of power vd D and light emitting diode formation respectively; Between the grid of driving transistors T2 and power input, be connected with capacitor C; Also comprise initialization transistor T3, the grid of initialization transistor T3 is connected initializing signal INIT simultaneously with the initialization end, and the output terminal of initialization transistor connects capacitor C.Wherein said transistor is thin film transistor (TFT) (TFT).

Because the residual charge before storing on the capacitor C between grid that is connected in driving transistors T2 and the power input can exert an influence to the data-signal DATA of output usually, reduces the display effect of light-emitting component D.Therefore be provided with initialization transistor T3.Pass through initializing signal INIT earlier to the residual charge initialization on the capacitor C; Behind specified magnitude of voltage initialization image element circuit; Again according to sweep signal SCAN and data-signal DATA actuating switch transistor T 1 and driving transistors T2; To light-emitting component D output proper data signal DATA, to guarantee the display effect of light-emitting component D.All transistorized structures all are symmetrical in the present embodiment, so each transistorized source electrode can exchange with drain electrode.

As shown in Figure 3, when A stage image element circuit was not worked, switching transistor T1, driving transistors T2 and initialization transistor T3 were in cut-off state.The B stage is before image element circuit is started working, according to initializing signal INIT, and conducting initialization transistor T3, switching transistor T1 and driving transistors T2 remain off.Get into the C stage after initialization is accomplished, switching transistor T1 is according to sweep signal SCAN conducting, and sweep signal SCAN is sent on the capacitor C through switching transistor T1.Simultaneously, driving transistors T2 is switched on according to data-signal DATA, and electric current is transported on the light-emitting component D, and this moment, initialization transistor T3 was ended.D is in the stage, and after sweep signal SCAN and data-signal DATA changed closed condition into, switching transistor T1 was ended, and driving transistors T2 is because the charging voltage on the capacitor C can maintain the arrival of conducting state up to next frame always.From the B stage begin to D stage be repeatedly always.

Claims

1.AMOLED image element circuit structure; Have switching transistor and driving transistors; The grid of switching transistor is connected sweep signal and data-signal respectively with data terminal, and the output terminal of switching transistor connects the grid of driving transistors, and the power input of driving transistors is connected power supply and light-emitting component respectively with output terminal; Between the grid of driving transistors and power input, be connected with electric capacity; It is characterized by: also comprise initialization transistor, the grid of initialization transistor is connected initializing signal simultaneously with the initialization end, and the output terminal of initialization transistor connects electric capacity.

2. the image element circuit structure of AMOLED as claimed in claim 1, it is characterized by: described transistor is thin film transistor (TFT).

3. according to claim 1 or claim 2 the image element circuit structure of AMOLED, it is characterized by: described light-emitting component is a light emitting diode.