CN103117040B - Image element circuit, display device and display drive method - Google Patents

Abstract

This application discloses a kind of image element circuit, display device and display drive method, the first threshold information of voltage of transistor seconds and the Second Threshold information of voltage of light-emitting component is extracted by current offset mode, and together with the half-tone information of pixel as the reference voltage of the first electric capacity, thus in glow phase, make to be had nothing to do with above-mentioned first threshold information of voltage and Second Threshold information of voltage by the drive current of light-emitting component, the unevenness of the threshold voltage shift of fine compensation TFT device and OLED or display panel TFT device threshold voltage everywhere, by voltage-programming mode, half-tone information is stored to the first electric capacity, achieve data input fast, and, simple circuit structure adds the aperture opening ratio of pixel and the yield rate of display device, reduce production cost.

Description

Image element circuit, display device and display drive method

Technical field

The application relates to display device technical field, particularly relates to a kind of image element circuit, display device and display drive method.

Background technology

Organic Light Emitting Diode (OrganicLight-EmittingDiode, OLED) display, because having the advantages such as high brightness, high-luminous-efficiency, wide viewing angle and low-power consumption, is extensively studied by people in recent years, and is applied to rapidly in the middle of display of new generation.The type of drive of OLED display can be passive waked-up (PassiveMatrixOLED, PMOLED) and driven with active matrix (ActiveMatrixOLED, AMOLED) two kinds.Although passive waked-up is with low cost, there is cross-talk phenomenon and can not realize high-resolution display, and passive waked-up electric current is large, reduces the serviceable life of OLED.By contrast, driven with active matrix mode arranges the different transistor of number on each pixel as current source, and avoid cross-talk, required drive current is less, and power consumption is lower, the life-span of OLED is increased, can realize high-resolution display.

The image element circuit of tradition AMOLED is simple two Thin Film Transistor (TFT) (ThinFilmTransistor, TFT) structures, and as shown in Figure 1, this image element circuit 10 comprises switching transistor 13, electric capacity 16, driving transistors 14 and illuminating part OLED15.The control signal that switching transistor 13 responds from scan control line SCAN12 is sampled from the data-signal of data line DATA11.Electric capacity 16 closes the voltage data signal of having no progeny and preserving and sampling at switching transistor 13.The input voltage that driving transistors 14 retains according to electric capacity 16 between given light emission period supplies output current.The light that illuminating part OLED15 matches by sending its brightness and data-signal from the output current of driving transistors 14.According to the electric current and voltage formula of transistor, the electric current that driving transistors 14 flows through can be expressed as:

I _DS=1/2μ _nC _oxW/L(V _G-V _OLED-V _TH) ²……（1）

Wherein, I _dSdrain electrode for driving transistors 14 flows to the drain current of source electrode, μ _nfor the effective mobility of TFT device, C _oxfor the gate capacitance of TFT device unit area, W, L are respectively effective channel width and the channel length of TFT device, V _gfor the grid voltage of TFT device, V _oLEDthe bias voltage on OLED15, V _tHfor the threshold voltage of TFT device, V _oLEDrelevant to the threshold voltage of OLED15.

Although this circuit structure is simple, can not compensation for drive transistor 14 threshold voltage V _tHdrift, OLED15 threshold voltage shift or cause the threshold voltage V of panel TFT device everywhere because TFT device adopts polycrystalline silicon material to make _tHunevenness.As driving transistors 14 threshold voltage V _tH, there is drift or V everywhere on panel in OLED15 threshold voltage _tHvalue inconsistent time, according to formula (1) drive current I _dSwill change, and pixels different on panel because of bias voltage difference drift situation also different, the unevenness of Display panel will be caused like this.

Therefore, just current, in order to solve the V of TFT device _tHthe problem that drift brings, the technique that the image element circuit regardless of AMOLED adopts is polysilicon (poly-Si) technology, amorphous silicon (a-Si) technology or oxide semiconductor technology, and it all needs to provide threshold voltage V when forming image element circuit _tHcompensation mechanism.The current image element circuit having occurred much affording redress, these circuit roughly can be divided into two classes: voltage driven type image element circuit and current drive-type image element circuit.Current drive-type image element circuit mainly adopts current mirror or current source data current to be copied as by a certain percentage the mode of drive current to light illuminating part.Because OLED is current mode device, therefore employing current drive-type circuit can the very accurate drift of compensating threshold voltage and the difference of mobility.But when practical application, due to the parasitic capacitance effect on data line, the foundation of data current needs the longer time, and this problem is more outstanding when small area analysis, has had a strong impact on the actuating speed of circuit.Voltage driven type image element circuit has very fast charge/discharge rates relative to current drive-type image element circuit, can meet the needs of large area, high-resolution display.But many voltage driven type image element circuits are at compensating threshold voltage V _tHdrift time, need complicated circuit structure and introduce multi-strip scanning line, this makes the aperture opening ratio of pixel reduce and requires higher to the raster data model IC of outside, and adds line cost.

Consider above factor, one can as current mode circuit the unevenness of the threshold voltage shift of fine compensation TFT device or OLED or display panel TFT device threshold voltage everywhere, equally with voltage-type driving circuit can realize again data input fast, and circuit structure is simple, the few pixel-driving circuit of device count is used to have advantage clearly.

Summary of the invention

The application provides a kind of image element circuit, display device and display drive method, can the unevenness of the threshold voltage shift of fine compensation TFT device and OLED or display panel TFT device threshold voltage everywhere, and realize data input fast, and circuit structure is simple, increase the aperture opening ratio of pixel and the yield rate of display device, reduce production cost.

According to the first aspect of the application, the application provides a kind of image element circuit, comprising:

Light-emitting component;

Transistor seconds, its 3rd electrode is used for being connected to a bias current line, the 4th Electrode connection to described light-emitting component, for providing drive current for described light-emitting component;

First electric capacity, its first end is connected to second of described transistor seconds and controls pole, and the second end is connected to the data line for providing pixel grey scale information, for providing reference voltage for described transistor seconds;

The first transistor, its first electrode is used for being connected to described bias current line, second Electrode connection controls pole to described second, first controls pole for being connected to the sweep trace that provides sweep signal, for conducting under the control of described sweep signal, described transistor seconds conducting is made to comprise the first threshold information of voltage of transistor seconds, the Second Threshold information of voltage of light-emitting component and half-tone information with the reference voltage making the first electric capacity and provide.

According to the second aspect of the application, the application provides a kind of image element circuit, comprising:

Light-emitting component;

Transistor seconds, its 3rd electrode is used for being connected to a bias current line, the 4th Electrode connection to described light-emitting component, for providing drive current for described light-emitting component;

First electric capacity, its first end is connected to second of described transistor seconds and controls pole, and the second end is connected to a common node, for providing reference voltage for described transistor seconds;

The first transistor, its first electrode is used for being connected to described bias current line, second Electrode connection controls pole to described second, first controls pole for being connected to the sweep trace that provides sweep signal, for conducting under the control of described sweep signal, described transistor seconds conducting is made to comprise the first threshold information of voltage of transistor seconds, the Second Threshold information of voltage of light-emitting component and half-tone information with the reference voltage making the first electric capacity and provide.

According to the third aspect of the application, the application provides a kind of display device, comprising:

Display panel, comprises some as the first image element circuit above-mentioned;

Gate driver circuit, for providing sweep signal by described sweep trace to image element circuit;

Data drive circuit, for providing half-tone information by described data line to image element circuit, described data drive circuit also comprises bias current sources, voltage source and gate-controlled switch, and described bias current sources, voltage source provide bias current, supply voltage respectively by bias current alignment image element circuit;

Sequential control circuit, for scanning in a frame time in described sweep signal, control the state that described gate-controlled switch switches to bias current sources to be communicated with bias current line at data input phase, in the state that glow phase switches to described voltage source to be communicated with bias current line.

According to the fourth aspect of the application, the application provides a kind of display device, comprising:

Display panel, comprises some image element circuits as above-mentioned the second;

Gate driver circuit, for providing sweep signal by described sweep trace to image element circuit;

Data drive circuit, for extracting described first threshold information of voltage and Second Threshold information of voltage from described bias current line, described data drive circuit comprises bias current sources, data voltage source, voltage source and gate-controlled switch, and described bias current sources, data voltage source, voltage source provide bias current respectively by bias current alignment image element circuit, comprise driving voltage, the supply voltage of described first threshold information of voltage and Second Threshold information of voltage and half-tone information;

Sequential control circuit, for scanning in a frame time in described sweep signal, controls the state that described gate-controlled switch switches to bias current sources to be communicated with bias current line in threshold value extraction pattern; Scan in another frame time in described sweep signal, control the state that described gate-controlled switch switches to described data voltage source to be communicated with bias current line at the data input phase of light-emitting mode, in the state that the glow phase of light-emitting mode switches to described voltage source to be communicated with bias current line.

According to the 5th aspect of the application, the application provides a kind of display drive method, and described method is based on the first display device above-mentioned, and described method comprises: described sweep signal is scanned a frame time and is divided into data input phase and glow phase; At described data input phase, be that described transistor seconds providing package is containing described first threshold information of voltage, the Second Threshold information of voltage of light-emitting component and the reference voltage of half-tone information by current offset mode; In described glow phase, provide supply voltage to described transistor seconds, make described transistor seconds provide the drive current irrelevant with described first threshold information of voltage and Second Threshold information of voltage for light-emitting component.

According to the 6th aspect of the application, the application provides a kind of display drive method, described method is based on above-mentioned the second display device, described method comprises: under the threshold value extraction pattern that described sweep signal scans a frame time, extract described first threshold information of voltage and Second Threshold information of voltage by current offset mode from described bias current line; Described sweep signal is scanned another frame time and is divided into data input phase and glow phase, at described data input phase, be the reference voltage of described transistor seconds providing package containing described first threshold information of voltage, Second Threshold information of voltage and half-tone information by voltage-programming mode; In described glow phase, provide supply voltage to described transistor seconds, make described transistor seconds provide the drive current irrelevant with described first threshold information of voltage and Second Threshold information of voltage for light-emitting component.

The beneficial effect of the application is:

By providing a kind of image element circuit, display device and display drive method, the first threshold information of voltage of transistor seconds and the Second Threshold information of voltage of light-emitting component is extracted by current offset mode, and together with the half-tone information of pixel as the reference voltage of the first electric capacity, thus in glow phase, make to be had nothing to do with above-mentioned first threshold information of voltage and Second Threshold information of voltage by the drive current of light-emitting component, the unevenness of the threshold voltage shift of fine compensation TFT device and OLED or display panel TFT device threshold voltage everywhere, by voltage-programming mode, half-tone information is stored to the first electric capacity, achieve data input fast, and, simple circuit structure adds the aperture opening ratio of pixel and the yield rate of display device, reduce production cost.

Accompanying drawing explanation

Fig. 1 is the uncompensated two TFT image element circuits of prior art;

Fig. 2 is the structural drawing of the display device of the embodiment of the present application one;

Fig. 3 is the structural drawing of the data drive circuit 53 of the embodiment of the present application one;

Fig. 4 is the structural drawing of the image element circuit 56 of the embodiment of the present application one;

Fig. 5 is a kind of signal timing diagram of display device in display driver process of the embodiment of the present application one;

Fig. 6 is the structural drawing of the image element circuit 56 of the embodiment of the present application two;

Fig. 7 is a kind of signal timing diagram of display device in display driver process of the embodiment of the present application two;

Fig. 8 is the structural drawing of the data drive circuit 53 of the embodiment of the present application three;

Fig. 9 is the structural drawing of the image element circuit 56 of the embodiment of the present application three;

Figure 10 is a kind of signal timing diagram of display device in display driver process of the embodiment of the present application three;

Figure 11 is the structural drawing of the image element circuit 56 of the embodiment of the present application four;

Figure 12 is the schematic diagram increasing precharge power supply 46 in the display device of other embodiments of the application.

Embodiment

By reference to the accompanying drawings the present invention is described in further detail below by embodiment.

First some terms are described.Transistor can be the transistor of any structure, such as field effect transistor (FieldEffectTransistor, FET) or bipolar transistor (BipolarJunctionTransistor, BJT).When transistor is BJT, it controls the base stage B that pole refers to BJT, and first and second electrode refers to collector C and the emitter E of BJT respectively; When transistor is FET, it controls the grid G that pole refers to FET, and first and second electrode (i.e. current lead-through pole) refers to drain D and the source S of FET respectively.Transistor in display device is generally TFT device, now, the control pole of transistor is the grid G of TFT device, first and second electrode refers to drain D and the source S of TFT device respectively, when transistor is as on-off element, its drain D and source S can be exchanged, and namely first, second electrode also can refer to source S and the drain D of TFT device respectively.It is follow-up that to carry the 3rd, the 4th electrode similar too.

Embodiment one:

Please refer to Fig. 2, Fig. 2 shows the structure of the display device of the application first embodiment, and it mainly comprises display panel, gate driver circuit 52 and data drive circuit 53.Display panel comprises some pel arrays 51.Wherein, pel array 51 is formed by matrix-style arrangement by N capable M row image element circuit 56, and namely this pel array 51 is that N is capable, M row, and wherein N, M are positive integer.Usually, the same a line image element circuit 56 in pel array 51 is all connected to same sweep trace 57, and the same row image element circuit 56 in pel array 51 is connected to same data line 55 and bias current line 54.Gate driver circuit 52 is for providing sweep signal by sweep trace 57 to image element circuit 56.Data drive circuit 53 is for providing half-tone information by data line 55 to image element circuit, be transferred in corresponding pixel cell to realize gradation of image by data line 55 by half-tone information, and for image element circuit 56 provides bias current sources 47, voltage source 45 and gate-controlled switch 411, bias current sources 47 provides bias current, and the final display that voltage source 45 is image element circuit 56 provides supply voltage.

It should be noted that, although pel array 51 is with N × Metzler matrix arranged in form, but in order to graphical simplicity, the pel array 51 shown in Fig. 2 is only with 2 × 2 matrix arrangement, and other 3 × 4 matrix arrangement, 5 × 5 matrix arrangement etc. all can be selected according to actual conditions.

Please refer to Fig. 3, above-mentioned data drive circuit 53 mainly comprises digital analog converter 49, output buffering 48, voltage source 45, bias current sources 47 and gate-controlled switch 411 form.Wherein, digital analog converter 49 receives the digital signal and the control signal that come from the sign half-tone information of bus 410, and under control of the control signal digital signal is changed into simulating signal by export buffering 48 output on data line 55, bias current sources 47 is for providing bias current, gate-controlled switch 411 is controlled by a sequential control circuit, and voltage source 45, bias current sources 47 are coupled with bias current line 54 by gate-controlled switch 411.It should be noted that, in the present embodiment, sequential control circuit is contained in bus 410, and therefore, bus 410 1 aspect needs to provide half-tone information, timing control signal also will be provided to control gate-controlled switch 411 and digital to analog converter etc. on the other hand.

Please refer to Fig. 4, above-mentioned image element circuit 56 mainly comprises: an Organic Light Emitting Diode 29 is as light-emitting component, first electric capacity 27, second electric capacity 26, be provided with the first transistor 24 of the first control pole, the first electrode and the second electrode, and be provided with the transistor seconds 25 of the second control pole, the 3rd electrode and the 4th electrode, for simplicity, set a memory node 28(i.e. first end of the first electric capacity 27 here).First controls pole is coupled to sweep trace 57, and the first electrode coupling is to bias current line 54, and bias current line 54 can switch between bias current sources 47 and voltage source 45 due to the action of gate-controlled switch 411; Second controls pole is coupled to the second electrode, 3rd electrode coupling is to bias current line 54,4th electrode coupling is to the anode of Organic Light Emitting Diode 29, the bias current that bias current sources 47 provides can trigger the first transistor 24 and the first threshold information of voltage of transistor seconds 25 and the Second Threshold information of voltage of Organic Light Emitting Diode 29 are stored to the first electric capacity 27 by transistor seconds 25, thinks that transistor seconds 25 provides reference voltage; The first end of the first electric capacity 27 is coupled to the second electrode, and the second end is coupled to data line 55, and data line 55 can provide half-tone information or reference potential, and the 3rd end of the second electric capacity 26 is coupled to sweep trace 57, and the 4th end is coupled to the second electrode; The negative electrode of Organic Light Emitting Diode 29 is coupled to ground wire.

During specific implementation, bias current line 54 is coupled in the bias current sources 47 of 10 μ A, for its image element circuit 56 be coupled provides the bias current of 10 μ A.Sweep trace 57 can be coupled on certain horizontal drive circuit of gate driver circuit 52, for providing selection or non-select signal for some or one-row pixels circuit 56, such as, if sweep trace 57 is charged to 15V, be coupled image element circuit 56 can be made to be in the following data input selection stage, if sweep trace 57 is charged to-5V, be coupled image element circuit 56 can be made to be in the following data input non-selection stage.Certainly, above-mentioned numerical value is citing, and other numerical value can be selected during practical application to be not limited only to this.

Please refer to Fig. 5, Fig. 5 is a kind of signal timing diagram of image element circuit 56 shown in Fig. 4, wherein SCAN [1] sweep signal that is the first row pixel, by that analogy.A kind of display driver process of image element circuit 56 shown in Fig. 4 is specifically described, i.e. the display drive method of the embodiment of the present application one below in conjunction with Fig. 5.

As shown in Figure 5, the time that whole sweep signal scans a frame is divided into data input phase and glow phase.Wherein at data input phase, the image element circuit 56 of often going is divided into again data input selection stage and data input non-selection stage.When the level of the sweep trace 57 be coupled with image element circuit 56 is high, then image element circuit 56 is in the data input selection stage; When the level of the sweep trace 57 be coupled with image element circuit 56 is low, then image element circuit 56 is in the data input non-selection stage.

In the data input selection stage, because bus 410 controls gate-controlled switch 411, bias current line 54 is coupled in bias current sources 47, and provides a constant bias current.When the sweep trace 57 be coupled with image element circuit 56 becomes high level, the first transistor 24 is in conducting state, makes image element circuit 56 be in the data input selection stage.Now, the bias current in bias current line 54 charges to the first electric capacity 27 by the first transistor 24, and charge namely to memory node 28, therefore the current potential of memory node 28 can slowly raise.Memory node 28 is coupled to, so transistor seconds 25 can become conducting state from cut-off state gradually because of the rising of memory node 28 current potential because second of transistor seconds 25 controls pole.After transistor seconds 25 conducting, the bias current in bias current line 54 partly will flow through the 3rd electrode and the 4th electrode of transistor seconds 25, and this size of current flowing through transistor seconds 25 is:

$I_{\mathrm{DS}2}=\frac{1}{2}{\mathrm{\μ}}_n{C}_{\mathrm{ox}}\frac{W}{L}{(V_{\mathrm{store}}-V_{\mathrm{OLED}}-V_{\mathrm{TH}2})}^2......\left(2\right)$

Wherein, μ _n, C _ox, W, L and V _tH2be respectively the effective mobility of transistor seconds 25, unit area gate capacitance, channel width, channel length and first threshold voltage.V _store, V _oLEDthen be respectively the voltage on the voltage of memory node 28 and Organic Light Emitting Diode 29.By formula (2), can find out, the electric current flowing through transistor seconds 25 increases with the current potential rising of memory node 28.Finally, I is worked as _dS2equal bias current I _bIAStime, bias current I _bIASset up completely in image element circuit 56, now the current potential V of memory node 28 _storecan be derived as by formula (2):

$V_{\mathrm{store}}=\sqrt{\frac{{2I}_{\mathrm{BIAS}}L}{{\mathrm{\μ}}_n{C}_{\mathrm{ox}}W}}+V_{\mathrm{OLED}}+V_{\mathrm{TH}2}......\left(3\right)$

Herein, I _bIASfor bias current, V _oLEDcan think the bias voltage of Organic Light Emitting Diode 29, it is relevant to the Second Threshold voltage of Organic Light Emitting Diode 29.Can be found by (3), now the current potential of memory node 28 contains the first threshold information of voltage of transistor seconds 25 and the Second Threshold information of voltage of Organic Light Emitting Diode 29.

In the data input selection stage, data line 55 can synchronously provide the data voltage representing half-tone information, and setting its magnitude of voltage is herein V _data.This data voltage V _datawith the storage voltage V of memory node 28 _store, be stored in the first electric capacity 27 two ends respectively, then the voltage difference on the first electric capacity 27 is: V _data-V _store.

Now, the quantity of electric charge of memory node 28 can be expressed as:

Q _A=(V _store-V _data)C1+(V _store-V _H)C2+(V _store-V _OLED-V _TH2)C _g2……（4）

Wherein, V _hfor the level value of data input selection stage sweep signal, C _g2for the gate capacitance of transistor seconds, C1 and C2 is respectively the capacitance of the first electric capacity 26 and the second electric capacity 27.

Terminate in the data input selection stage, the data input non-selection stage is when starting, sweep trace 57 becomes low level from high level, this change in voltage not only makes the first transistor 24 become cut-off state from conducting state, also be coupled to memory node 28 by the second electric capacity 26, make the current potential of memory node 28 become the first negative potential, transistor seconds 25 entered and remain off state in the data input non-selection stage.

In the data input non-selection stage, the first transistor 24 and transistor seconds 25 are all in cut-off state, and bias current line 54 and data line 55 provide bias current respectively for other image element circuits 56 and characterize the data voltage of half-tone information.It should be noted that, in this process, the level change of data line 55 may be coupled to memory node 28 by the first electric capacity 27, the current potential of memory node 28 is raised, therefore, in order to ensure transistor seconds 25 in the non-selection stage not conducting of data input, the first negative potential of memory node 28 needs enough low.

At above-mentioned data input phase, all pixels enter data input selection stage and data input non-selection stage line by line, and the same time only has one-row pixels to be in the data input selection stage, and in this data input selection stage, above-mentioned first threshold information of voltage, Second Threshold information of voltage and half-tone information are stored in the memory node 28 of pixel as reference voltage.

After data input phase, it is and then glow phase.In glow phase, because bus 410 controls gate-controlled switch 411, bias current line 54 disconnects the connection with bias current sources 47, and be coupled on voltage source 45, this voltage source 45, for providing constant supply voltage for all image element circuits be coupled with bias current line 54, makes transistor seconds 25 provide a drive current for Organic Light Emitting Diode 29.Data line 55 now also provides a reference potential, and this magnitude of voltage is V _ref.On data line 55, the variation of current potential can be coupled in memory node 28 by the first electric capacity 27, makes the current potential of memory node 28 become V _hIGH.It should be noted that memory node 28 is in suspended state, and the quantity of electric charge wherein does not change in data input non-selection stage and glow phase.It can be expressed as in glow phase:

Q _A=(V _HIGH-V _L)C2+(V _HIGH-V _ref)C1+(V _HIGH-V _OLED-V _TH2)C _g2……（5）

Wherein, V _lit is the magnitude of voltage of the non-selection stage sweep signal of data input.Formula (4) is updated in formula (5), can is in the hope of the expression formula of VHIGH:

$V_{\mathrm{HIGH}}=V_{\mathrm{store}}+\frac{(V_{\mathrm{ref}}-V_{\mathrm{data}})C1-(V_H-V_L)C2}{C1+C2+C_{g2}}......\left(6\right)$

$=V_{\mathrm{OVERDRIVE}}+V_{\mathrm{TH}2}+V_{\mathrm{OLED}}$

Wherein, V _oVERDRIVEhave nothing to do with above-mentioned first threshold voltage and Second Threshold voltage.Can be released by formula (6), in glow phase, the drive current that Organic Light Emitting Diode 29 flows through is:

I _OLED=1/2μ _nC _oxW/L(V _HIGH-V _OLED-V _TH2) ²=1/2μ _nC _oxW/L(V _OVERDRIVE) ²……（7）

Can be found by formula (7), in glow phase, the first threshold voltage of the drive current that Organic Light Emitting Diode 29 flows through and transistor seconds 25 and the Second Threshold voltage of Organic Light Emitting Diode 29 have nothing to do, namely the unevenness being changed the display caused by these two kinds of element threshold voltages can be compensated, on the other hand, due to above-mentioned drive current I _oLEDhave nothing to do with the first threshold voltage of transistor seconds 25, then can compensate because TFT device adopts polycrystalline silicon material to make and cause the threshold voltage V of panel TFT device everywhere _tHunevenness, ensure that the homogeneity of the display on display panel.

On the whole, the work of display device is divided into data input phase and glow phase, and wherein data input phase is divided into again data input selection stage and data input non-selection stage.Pixel was controlled to be in opening by sweep trace 57 in the data input selection stage, and the bias current that being coupled to, the bias current line 54 of bias current sources 47 provides flows through image element circuit 56, and produces corresponding reference voltage at memory node 28.This stage Organic Light Emitting Diode 29 can be luminous due to flowing through of bias current.In the data input non-selection stage, because the variation of sweep trace 57 negative sense makes image element circuit 56 be in closed condition, Organic Light Emitting Diode 29 can not be luminous.In glow phase, data line 55 provides a high reference potential, bias current line 54 is also coupled on voltage source 45, on display panel, all image element circuits 56 all start conducting, and the size of current of conducting is relevant to the data voltage that the data input selection stage inputs, the Second Threshold voltage of the drive current namely on Organic Light Emitting Diode 29 and the first threshold voltage of transistor seconds 25 and Organic Light Emitting Diode 29 has nothing to do, and relevant with half-tone information.On average, the average effect of the overall brightness of the display panel light that to be Organic Light Emitting Diode 29 send in data input selection stage and glow phase.

Embodiment two:

Please refer to Fig. 6, mainly be with the difference of embodiment one, in display device, gate driver circuit 52 also provides one at the data input phase control line 64 contrary with sweep trace level, and image element circuit 56 mainly comprises: an Organic Light Emitting Diode 29 is as light-emitting component, first electric capacity 27, be provided with the first control pole, the first transistor 24 of the first electrode and the second electrode is as switch control module, and be provided with the second control pole, the transistor seconds 25 of the 3rd electrode and the 4th electrode is as driver module, for simplicity, here a memory node 68(i.e. first end of the first electric capacity 27 is set).First controls pole is coupled to sweep trace 57, and the first electrode coupling is to bias current line 54, and bias current line 54 can switch between bias current sources 47 and voltage source 45 due to the action of gate-controlled switch 411; Second controls pole is coupled to the second electrode, 3rd electrode coupling is to bias current line 54,4th electrode coupling is to the anode of Organic Light Emitting Diode 29, the bias current that bias current sources 47 provides can trigger the first transistor 24 and the first threshold information of voltage of transistor seconds 25 and the Second Threshold information of voltage of Organic Light Emitting Diode 29 are stored to the first electric capacity 27 by transistor seconds 25, thinks that transistor seconds 25 provides reference voltage; The first end of the first electric capacity 27 is coupled to the second electrode, and the second end is coupled to data line 55, and data line 55 can provide half-tone information or reference potential; The negative electrode of Organic Light Emitting Diode 29 is coupled to control line 64.

Please refer to Fig. 7, Fig. 7 is a kind of signal timing diagram of image element circuit 56 shown in Fig. 6, wherein SCAN [1] sweep signal that is the first row pixel, the control signal on the control line that CNTR [1] is the first row pixel, by that analogy.A kind of display driver process of image element circuit 56 shown in Fig. 6 is specifically described, i.e. the display drive method of the embodiment of the present application two below in conjunction with Fig. 7.

As shown in Figure 7, the time that whole sweep signal scans a frame is divided into data input phase and glow phase.Wherein at data input phase, the image element circuit 56 of often going is divided into again data input selection stage and data input non-selection stage.When the level of the sweep trace 57 be coupled with image element circuit 56 is high, then image element circuit 56 is in the data input selection stage; When the level of the sweep trace 57 be coupled with image element circuit 56 is low, then image element circuit 56 is in the data input non-selection stage.

In the data input selection stage, because bus 410 controls gate-controlled switch 411, bias current line 54 is coupled in bias current sources 47, and provides a constant bias current.When the sweep trace 57 be coupled with image element circuit 56 becomes high level, the first transistor 24 is in conducting state, makes image element circuit 56 be in the data input selection stage.Now, control line 64 is low level, and the bias current in bias current line 54 charges to memory node 68 by the first transistor 24, and therefore the current potential of memory node 68 can slowly raise.Memory node 68 is coupled to, so transistor seconds 25 can become conducting state from cut-off state gradually because of the rising of memory node 68 current potential because second of transistor seconds 25 controls pole.After transistor seconds 25 conducting, the bias current in bias current line 54 partly will flow through the 3rd electrode and the 4th electrode of transistor seconds 25, and this size of current flowing through transistor seconds 25 can still be represented by above-mentioned formula (2).

By formula (2), can find out, the electric current flowing through transistor seconds 25 increases with the current potential rising of memory node 68.Finally, I is worked as _dS2when equaling bias current, bias current is set up completely in image element circuit 56, now the current potential V of memory node 68 _storecan by above-mentioned formula (3) similar expression.

Can be found by (3), now the current potential of memory node 68 contains the first threshold information of voltage of transistor seconds 25 and the Second Threshold information of voltage of Organic Light Emitting Diode 29.

It should be noted that in the data input selection stage, data line 55 can synchronously provide the data voltage representing half-tone information, i.e. half-tone information, and setting its magnitude of voltage is herein V _data.This data voltage V _datawith the storage voltage V of memory node 68 _store, be stored in the first electric capacity 27 two ends respectively, then the voltage difference on the first electric capacity 27 is: V _data-V _store.

At the end of the data input selection stage, the data input non-selection stage is when starting, sweep trace 57 becomes low level from high level, thus make the first transistor 24 become cut-off state from conducting state, the level of control line 64 becomes height from low simultaneously, makes transistor seconds 25 and Organic Light Emitting Diode 29 also all be in and remain on cut-off state.

In the data input non-selection stage, the first transistor 24 and transistor seconds 25 are all in cut-off state, and bias current line 54 and data line 55 provide difference bias current for other pixels and characterize the data voltage of half-tone information.It should be noted that, in this process, the level change of data line 55 may be coupled to memory node 68 by the first electric capacity 27, and the current potential of memory node 68 is raised, therefore, the high level of control line 64 is enough high to guarantee that the second crystal 25 is in the non-selection stage not conducting of data input.

At above-mentioned data input phase, all pixels enter data input selection stage and data input non-selection stage line by line, and the same time only has one-row pixels to be in the data input selection stage, and at this moment above-mentioned first threshold information of voltage, Second Threshold information of voltage and half-tone information are stored in the memory node 68 of pixel as reference voltage.

After data input phase, it is and then glow phase.In glow phase, because bus 410 controls gate-controlled switch 411, bias current line 54 disconnects the connection with bias current sources 47, and be coupled on a voltage source 45, this voltage source 45 provides constant supply voltage for all image element circuits be coupled with bias current line 54, makes transistor seconds 25 provide a drive current for Organic Light Emitting Diode 29.All control lines 64 also become low level again.Now, data line 55 also provides a reference potential, and this magnitude of voltage is V _ref.On data line 55, the variation of current potential can be coupled in memory node 68 by the first electric capacity 27, and the current potential of memory node 68 is become:

$V_{\mathrm{HIGH}}=V_{\mathrm{store}}+\frac{(V_{\mathrm{ref}}-V_{\mathrm{data}})\×C1}{C_{g2}+C1}$

$=\sqrt{\frac{{2I}_{\mathrm{BIAS}}L}{{\mathrm{\μ}}_n{C}_{\mathrm{ox}}W}}+\frac{(V_{\mathrm{ref}}-V_{\mathrm{data}})\×C1}{C_{g2}+C1}+V_{\mathrm{OLED}}+V_{\mathrm{TH}2}......\left(8\right)$

$=V_{\mathrm{OVERDRIVE}}+V_{\mathrm{OLED}}+V_{\mathrm{TH}2}$

C _g2for the gate capacitance of transistor seconds 25, V _oVERDRIVEbe the overdrive voltage of transistor seconds 25, the first threshold voltage of its value and transistor seconds 25 or the Second Threshold voltage of Organic Light Emitting Diode 29 have nothing to do.

Can be released by formula (8), in glow phase, the drive current that Organic Light Emitting Diode 29 flows through is:

I _OLED=1/2μ _nC _oxW/L(V _HIGH-V _OLED-V _TH2) ²=1/2μ _nC _oxW/L(V _OVERDRIVE) ²......（9）

By formula (9), can find, in glow phase, the first threshold voltage of the drive current that Organic Light Emitting Diode 29 flows through and transistor seconds 25 and the Second Threshold voltage of Organic Light Emitting Diode 29 have nothing to do, namely the unevenness being changed the display caused by these two kinds of element threshold voltages can be compensated, on the other hand, due to above-mentioned drive current I _oLEDhave nothing to do with the first threshold voltage of transistor seconds 25, then can compensate because TFT device adopts polycrystalline silicon material to make and cause the threshold voltage V of panel TFT device everywhere _tHunevenness, ensure that the homogeneity of the display on display panel.

The present embodiment owing to eliminating the second electric capacity 26 relative to embodiment one, further reduces elemental area, adds pixel aperture ratio.

Embodiment three:

Please refer to Fig. 8 and Fig. 9, mainly be with the difference of embodiment one, in display device, as shown in Figure 8, data drive circuit 53 also comprises by analog-digital converter 104, input buffer 103, exterior storage 105, totalizer 106, the data voltage source that digital analog converter 107 and output buffer 108 form, wherein, analog-digital converter 104 is coupled to the output terminal of bias current sources 47 by input buffer 103, and complete and being coupled and disconnection of bias current line 54 by gate-controlled switch 411, above-mentioned each device function carries out correspondence and describes in following display driver process.As shown in Figure 9, image element circuit 56 mainly comprises: an Organic Light Emitting Diode 29 is as light-emitting component, second electric capacity 26, first electric capacity 27, be provided with the first control pole, the first electrode and the second electrode the first transistor 24 as switch control module, and be provided with the second control pole, the 3rd electrode and the 4th electrode transistor seconds 25 as driver module, for simplicity, set a memory node 88(i.e. first end of the first electric capacity 27 here).First controls pole is coupled to sweep trace 57, and the first electrode coupling is to bias current line 54, and bias current line 54 can switch between bias current sources 47, output buffer 108 and voltage source 45 due to the action of gate-controlled switch 411; Second controls pole is coupled to the second electrode, 3rd electrode coupling is to bias current line 54,4th electrode coupling is to the anode of Organic Light Emitting Diode 29, and the bias current that bias current sources 47 provides can trigger the first transistor 24 and the first threshold information of voltage of transistor seconds 25 and the Second Threshold information of voltage of Organic Light Emitting Diode 29 are stored to the first electric capacity 27 and exterior storage 105 by transistor seconds 25; The first end of the first electric capacity 27 is coupled to the second electrode, and the second end is coupled to common node 83, and common node 83 switches between common node current potential and reference potential, and the 3rd end of the second electric capacity 26 is coupled to sweep trace 57, and the 4th end is coupled to the second electrode; The negative electrode of Organic Light Emitting Diode 29 is coupled to ground wire.Common node 83 can be the node that a line or all row of whole display panel are shared.

In Fig. 8, exterior storage 105 and totalizer 106 grade can be separately set in outside data drive circuit 53, form the function element that can share.

Please refer to Figure 10, Figure 10 display be a kind of signal timing diagram of image element circuit 56 shown in Fig. 9, wherein SCAN [1] sweep signal that is the first row pixel, by that analogy.A kind of display driver process of image element circuit 56 shown in Fig. 9 is specifically described, i.e. the display drive method of the embodiment of the present application three below in conjunction with Fig. 8 and Figure 10.

Shown in Fig. 8 and Figure 10 is a kind of driving method adopting external compensation, this type of drive is main first will need the threshold voltage information of driver module and the light-emitting component compensated extract and be stored in exterior storage with the form of digital signal, when input gray level information, then stored threshold voltage information and half-tone information are superposed the compensate function realizing threshold voltage together.Can be known by Figure 10, the whole driving process of external compensation can be carried out in both modes: one is that threshold value extracts pattern, and one is normal light-emitting mode.Wherein threshold value extraction pattern can perform once when display device switching on and shutting down, and all the other times are all operated in light-emitting mode; Or perform when display device switching on and shutting down once, in ensuing light-emitting mode, every a frame or a few frame time, the extraction of threshold voltage information is carried out to the pixel of certain a line, to refresh its threshold voltage information in exterior storage in real time.

In threshold value extraction pattern, the course of work of image element circuit 56 is divided into threshold value to extract the choice phase and threshold value extracts the non-selection stage.When the level of the sweep trace 57 be coupled with image element circuit 56 is high, then image element circuit 56 is in threshold value and extracts the choice phase; When the level of the sweep trace 57 be coupled with image element circuit 56 is low, then image element circuit 56 is in threshold value and extracts the non-selection stage.

Extract the choice phase in threshold value, because bus 401 controls gate-controlled switch 411, bias current line 54 is coupled in bias current sources 47, and provides a constant bias current.When the sweep trace 57 be coupled with image element circuit 56 becomes high level, the first transistor 24 is in conducting state, makes image element circuit 56 be in threshold value and extracts the choice phase.Now, the bias current in bias current line 54 charges to the first electric capacity 27 by the first transistor 24, and therefore the current potential of memory node 88 can slowly raise.Memory node 88 is coupled to, so transistor seconds 25 can become conducting state from cut-off state gradually because of the rising of memory node 88 current potential because second of transistor seconds 25 controls pole.After transistor seconds 25 conducting, the bias current in bias current line 54 partly will flow through the 3rd electrode and the 4th electrode of transistor seconds 25, and this size of current flowing through transistor seconds 25 can be represented by above-mentioned formula (2).As can be seen from formula (2), the electric current flowing through transistor seconds 25 increases with the current potential rising of memory node 88.Finally, I is worked as _dS2when equaling bias current, bias current is set up completely in image element circuit 56, now the current potential V of memory node 88 _storecan be represented by above-mentioned formula (3), current potential V _storecontain above-mentioned first threshold information of voltage and Second Threshold information of voltage.

Can be found by (3), now the current potential of memory node 88 contains the first threshold information of voltage of transistor seconds 25 and the Second Threshold information of voltage of Organic Light Emitting Diode 29.Because the voltage on memory node 88 is identical with the magnitude of voltage in bias current line 54, so information of voltage V in the analog-digital converter 104 meeting sample-offset current line 54 be now coupled with bias current line 54 _storeand convert thereof into digital signal and be input in exterior storage 105.

Terminate in the threshold value extraction choice phase, when the threshold value extraction non-selection stage starts, the level of sweep trace 57 becomes low level from high level.This change in voltage not only makes the first transistor 24 become cut-off state from conducting state, also be coupled to memory node 88 by the second electric capacity 26, make the current potential of memory node 88 become the first negative potential, transistor seconds 25 entered and remain off state in the data input non-selection stage.

Extract the non-selection stage in threshold value, the first transistor 24 and transistor seconds 25 are all in cut-off state, and bias current line 54 provides bias current for other image element circuits 56.Under threshold value extraction pattern, all pixels enter threshold value line by line and extract choice phase and threshold value extraction non-selection stage, and the first threshold information of voltage on memory node 88 and Second Threshold information of voltage are stored in storage chip 105.

Driving process in light-emitting mode is divided into data input phase and glow phase.At data input phase, because bus 410 controls gate-controlled switch 411, bias current line 54 disconnects the connection with bias current sources 47, and is coupled on digital analog converter 107 by output buffer 108, and for exporting a driving voltage, its driving voltage value is V _drive.Because the half-tone information from bus 410 superposes with the storage voltage in exterior storage 105 by totalizer 106 in advance, driving voltage V _drivethen can be included in the information of voltage V under threshold value extraction pattern _storewith the data voltage V representing half-tone information _data.When the sweep trace 57 be coupled with image element circuit 56 becomes high level, the first transistor 24 is in conducting state, makes image element circuit 56 be in the data input selection stage.Now, the driving voltage V in bias current line 54 _drivebe input in memory node 88 by the first transistor 24.

Now, the quantity of electric charge of memory node 88 can be expressed as:

Q _A=(V _drive-V ₀)C1+(V _drive-V _H)C2+(V _drive-V _OLED-V _th2)C _g2……（10）

Wherein, V _hfor the level value of data input selection stage sweep signal, V ₀the magnitude of voltage of data input phase common node, C _g2for the gate capacitance of transistor seconds, C1 and C2 is respectively the capacitance of the first electric capacity 26 and the second electric capacity 27.

Terminate in the data input selection stage, the data input non-selection stage is when starting, sweep trace 57 becomes low level from high level, this change in voltage not only makes the first transistor 24 become cut-off state from conducting state, also be coupled to memory node 88 by the second electric capacity 26, make the current potential of memory node 88 become the second negative potential, transistor seconds 25 entered and remain off state in the data input non-selection stage.

In the data input non-selection stage, the first transistor 24 and transistor seconds 25 are all in cut-off state, and bias current line 54 provides driving voltage for other pixels.

At above-mentioned data input phase, all pixels enter data input selection stage and data input non-selection stage line by line, and the first threshold information of voltage of transistor seconds 25, the Second Threshold information of voltage of Organic Light Emitting Diode 29 and half-tone information are stored in the memory node 88 of each pixel as reference voltage.At data input phase, common node 83 remains a constant potential V always ₀.

After data input phase, it is and then glow phase.In glow phase, because bus 410 controls gate-controlled switch 411, bias current line 54 disconnects and the connection of output buffer 108, and is coupled on voltage source 45, and this voltage source 45 provides constant supply voltage for all image element circuits be coupled with bias current line 54.Now the current potential of common node 83 is also by original constant potential V ₀become reference potential, the magnitude of voltage of reference potential is V _ref.On common node 83, the variation of current potential can be coupled in memory node 88 by the first electric capacity 27, makes the current potential of memory node 88 become V _hIGH.Should be noted that a bit, in data input non-selection stage and glow phase, memory node 88 is in suspended state, and the quantity of electric charge wherein does not change.It can be expressed as in glow phase:

Q _A=(V _HIGH-V _L)C2+(V _HIGH-V _ref)C1+(V _HIGH-V _OLED-V _TH2)C _g2……（11）

Wherein, V _lit is the magnitude of voltage of the non-selection stage sweep signal of data input.Formula (10) is updated in formula (11), can in the hope of V _hIGHexpression formula be:

$V_{\mathrm{HIGH}}=V_{\mathrm{dirve}}+\frac{(V_{\mathrm{ref}}-V_0)C1-(V_H-V_L)C2}{C1+C2+C_{g2}}$

$=V_{\mathrm{data}}+\frac{(V_{\mathrm{ref}}-V_0)C1-(V_H-V_L)C2}{C1+C2+C_{g2}}+V_{\mathrm{store}}......\left(12\right)$

$=V_{\mathrm{OVERDRIVE}}+V_{\mathrm{TH}2}+V_{\mathrm{OLED}}$

Wherein, V _oVERDRIVEbe the overdrive voltage of transistor seconds 25, the first threshold voltage of its value and transistor seconds 25 or the Second Threshold voltage of Organic Light Emitting Diode 29 have nothing to do.

Can be released by formula (12), in glow phase, the electric current that Organic Light Emitting Diode 29 flows through is:

I _OLED=1/2μ _nC _oxW/L(V _HIGH-V _OLED-V _TH2) ²=1/2μ _nC _oxW/L(V _OVERDRIVE) ²……（13）

By formula (13), can find, in glow phase, the electric current I that Organic Light Emitting Diode 29 flows through _oLEDhave nothing to do with the first threshold voltage of transistor seconds 25 and the Second Threshold voltage of Organic Light Emitting Diode 29, namely can compensate the unevenness being changed the display caused by these two kinds of element threshold voltages, on the other hand, due to above-mentioned drive current I _oLEDhave nothing to do with the first threshold voltage of transistor seconds 25, then can compensate because TFT device adopts polycrystalline silicon material to make and cause the threshold voltage V of panel TFT device everywhere _tHunevenness, ensure that the homogeneity of the display on display panel.

The advantage of the present embodiment three is, for embodiment one, two, due to by adopting external compensation mode, only need perform a subthreshold when starting shooting and extracting pattern, under display device all can be operated in light-emitting mode in other times; And in data writing process (the data input phase namely under light-emitting mode), do not need bias current, and directly adopt driving voltage to load on memory node 88 by above-mentioned first threshold information of voltage, Second Threshold information of voltage and half-tone information, adopt voltage-programming mode greatly can reduce the time of data write, thus increase frame proportion shared by fluorescent lifetime.Image element circuit be may be used for more in high resolving power or more large-area display device.In addition, adopt the mode of external compensation to simplify dot structure, reduce the number of control line.

Embodiment four:

Please refer to Figure 11, mainly be with the difference of embodiment three, in display device, gate driver circuit 52 also provides a control line 64 contrary with sweep trace level, and in image element circuit 56, eliminate the second electric capacity 26, be similar to and embodiment two is combined with embodiment three.Image element circuit, display device and display drive method repeat no more herein.

It should be noted that:

1, in other embodiments of display device, in the above-mentioned data input selection stage, the voltage in the voltage on memory node and bias current line 54 is identical, and the voltage that this voltage ratio voltage source 45 provides is much smaller.Therefore, come interim at a new frame, current potential in bias current line 54 just needs to be quickly pulled low to set up above-mentioned bias current, in order to accelerate this process, can arrange a precharge power supply 46 for each row, bias current sources 47, voltage source 45, precharge power supply 46 are coupled with bias current line 54 by gate-controlled switch 411.As shown in figure 12, the voltage V of this precharge power supply 46 _prefor:

$V_{\mathrm{pre}}=\sqrt{\frac{{2I}_{\mathrm{BIAS}}L}{{\mathrm{\μ}}_n{C}_{\mathrm{ox}}W}}+V_{\mathrm{OLED}0}+V_{\mathrm{TH}20}......\left(14\right)$

Here, V _tH20and V _oLED0the initial threshold of transistor seconds and the initial bias current potential of Organic Light Emitting Diode respectively.Precharge power supply 46 only needs to be connected to the time very short in bias current line 54 when frame is initial, just electric charge unnecessary in bias current line 54 can be bled off.

2, above-mentioned data drive circuit can be on a display panel integrated, also in integrated peripheral IC chip, then can fit on display panel.

Although 3 image element circuits 56 have employed Organic Light Emitting Diode as light-emitting component, in a further embodiment, other light emitting diodes also can be adopted as light-emitting component.

4, in embodiment one and embodiment three, the second electric capacity 26 can be realized by the increase control pole of the first transistor and the overlapping area of the second electrode, also can make independent electric capacity original paper.

5, in each embodiment of the application, transistor can be made up of oxide thin film transistor, also can be made up of polysilicon or amorphous silicon film transistor.

6, in other embodiments, sequential control circuit also can not be integrated in bus, and provides half-tone information primarily of bus, and sequential control circuit controls gate-controlled switch separately.

The each embodiment of the application adopts two TFT devices to build image element circuit, and its circuit structure is simple, not only can compensate the threshold voltage shift of TFT device, also can compensate the threshold drift of OLED 7, ensure that the homogeneity of display.In addition, in prior art, when the threshold voltage of TFT device becomes negative value, traditional voltage-type threshold compensation circuitry just cannot reoffer compensation, and adopt current offset mode to align negative threshold voltage in each embodiment of the application to have good compensating action, therefore have more superior effect, this point is very favourable in employing depletion mode transistor is as the display device of driving tube.

Above content is the further description done the application in conjunction with concrete embodiment, can not assert that the concrete enforcement of the application is confined to these explanations.For the application person of an ordinary skill in the technical field, under the prerequisite not departing from the application's design, some simple deduction or replace can also be made.

Claims (13)

1. an image element circuit, is characterized in that, comprising:

Light-emitting component;

Transistor seconds, its 3rd electrode is used for being connected to a bias current line, the 4th Electrode connection to described light-emitting component, for providing drive current for described light-emitting component; Bias current line is used for providing bias current, with the Second Threshold information of voltage of the first threshold information of voltage and light-emitting component that extract transistor seconds;

First electric capacity, its first end is connected to second of described transistor seconds and controls pole, and the second end is connected to the data line for providing pixel grey scale information, for providing reference voltage for described transistor seconds;

The first transistor, its first electrode is used for being connected to described bias current line, second Electrode connection controls pole to described second, first controls pole for being connected to the sweep trace that provides sweep signal, for conducting under the control of described sweep signal, described transistor seconds conducting is made to comprise the first threshold information of voltage of transistor seconds, the Second Threshold information of voltage of light-emitting component and half-tone information with the reference voltage making the first electric capacity and provide.

2. image element circuit as claimed in claim 1, it is characterized in that, the negative electrode of described light-emitting component is coupled to a ground wire, and described image element circuit also comprises the second electric capacity, and described second capacitive coupling controls between pole at sweep trace and second.

3. image element circuit as claimed in claim 1, it is characterized in that, the negative electrode of described light-emitting component is coupled to a control line, for obtaining the control signal contrary with sweep signal level from described control line.

4. an image element circuit, is characterized in that, comprising:

Light-emitting component;

Transistor seconds, its 3rd electrode is used for being connected to a bias current line, the 4th Electrode connection to described light-emitting component, for providing drive current for described light-emitting component; Bias current line is used for providing bias current, with the Second Threshold information of voltage of the first threshold information of voltage and light-emitting component that extract transistor seconds;

First electric capacity, its first end is connected to second of described transistor seconds and controls pole, and the second end is connected to a common node, for providing reference voltage for described transistor seconds; Described common node is the node that a line or all row of whole display panel are shared;

The first transistor, its first electrode is used for being connected to described bias current line, second Electrode connection controls pole to described second, first controls pole for being connected to the sweep trace that provides sweep signal, for conducting under the control of described sweep signal, make described transistor seconds conducting, what described bias current line provided comprises described first threshold information of voltage, the driving voltage of Second Threshold information of voltage and half-tone information is coupled to second of described transistor seconds and controls pole, the first threshold information of voltage of transistor seconds is comprised with the reference voltage making the first electric capacity provide, the Second Threshold information of voltage of light-emitting component and half-tone information.

5. image element circuit as claimed in claim 4, it is characterized in that, the negative electrode of described light-emitting component is coupled to a ground wire, and described image element circuit also comprises the second electric capacity, and described second capacitive coupling controls between pole at sweep trace and second.

6. image element circuit as claimed in claim 4, it is characterized in that, the negative electrode of described light-emitting component is coupled to a control line, for obtaining the control signal contrary with sweep signal level from described control line.

7. the image element circuit as described in claim 2 or 5, is characterized in that, the overlapping area that described second electric capacity controls pole and the second electrode by increase first realizes.

8. a display device, is characterized in that, comprising:

Display panel, comprises some image element circuits according to any one of claim 1-3;

Gate driver circuit, for providing sweep signal by described sweep trace to image element circuit;

Data drive circuit, for providing half-tone information by described data line to image element circuit, described data drive circuit also comprises bias current sources, voltage source and gate-controlled switch, and described bias current sources, voltage source provide bias current, supply voltage respectively by bias current alignment image element circuit;

Sequential control circuit, for scanning in a frame time in described sweep signal, control the state that described gate-controlled switch switches to bias current sources to be communicated with bias current line at data input phase, in the state that glow phase switches to described voltage source to be communicated with bias current line.

9. a display device, is characterized in that, comprising:

Display panel, comprises some image element circuits according to any one of claim 4-6;

Gate driver circuit, for providing sweep signal by described sweep trace to image element circuit;

Data drive circuit, for extracting described first threshold information of voltage and Second Threshold information of voltage from described bias current line, described data drive circuit comprises bias current sources, data voltage source, voltage source and gate-controlled switch, and described bias current sources, data voltage source, voltage source provide bias current respectively by bias current alignment image element circuit, comprise driving voltage, the supply voltage of described first threshold information of voltage and Second Threshold information of voltage and half-tone information;

Sequential control circuit, for scanning in a frame time in described sweep signal, controls the state that described gate-controlled switch switches to bias current sources to be communicated with bias current line in threshold value extraction pattern; Scan in another frame time in described sweep signal, control the state that described gate-controlled switch switches to described data voltage source to be communicated with bias current line at the data input phase of light-emitting mode, in the state that the glow phase of light-emitting mode switches to described voltage source to be communicated with bias current line.

10. display device as claimed in claim 9, is characterized in that, described data voltage source also comprises the analog-digital converter, exterior storage, totalizer and the digital analog converter that are connected successively, wherein:

Described gate-controlled switch is when the state that threshold value extraction pattern switches to bias current sources to be communicated with bias current line, described analog-digital converter extracts described first threshold information of voltage and Second Threshold information of voltage from bias current line again, and described first threshold information of voltage and Second Threshold information of voltage are stored to exterior storage;

Described gate-controlled switch is when the state that the data input phase of light-emitting mode switches to data voltage source to be communicated with bias current line, and described totalizer is used for described first threshold information of voltage that the described half-tone information that bus provided and exterior storage provide and Second Threshold information of voltage carries out superposing and exports a digital signal; Described digital analog converter, exports bias current line to for the driving voltage described digital signal being converted to analog signal form,

Described gate-controlled switch, when the state that the glow phase of light-emitting mode switches to voltage source to be communicated with bias current line, drives by described voltage source, for light-emitting component provides drive current.

11. 1 kinds of display drive methods, is characterized in that, described method is based on display device as claimed in claim 8, and described method comprises: described sweep signal is scanned a frame time and is divided into data input phase and glow phase; At described data input phase, be that described transistor seconds providing package is containing described first threshold information of voltage, the Second Threshold information of voltage of light-emitting component and the reference voltage of half-tone information by current offset mode; In described glow phase, provide supply voltage to described transistor seconds, make described transistor seconds provide the drive current irrelevant with described first threshold information of voltage and Second Threshold information of voltage for light-emitting component.

12. 1 kinds of display drive methods, it is characterized in that, described method is based on display device as claimed in claim 9, described method comprises: under the threshold value extraction pattern that described sweep signal scans a frame time, extract described first threshold information of voltage and Second Threshold information of voltage by current offset mode from described bias current line; Described sweep signal is scanned another frame time and is divided into data input phase and glow phase, at described data input phase, be the reference voltage of described transistor seconds providing package containing described first threshold information of voltage, Second Threshold information of voltage and half-tone information by voltage-programming mode; In described glow phase, provide supply voltage to described transistor seconds, make described transistor seconds provide the drive current irrelevant with described first threshold information of voltage and Second Threshold information of voltage for light-emitting component.

13. display drive methods as claimed in claim 12, it is characterized in that, when display device adopts display device as claimed in claim 10, described method comprises:

Under the threshold value extraction pattern that described sweep signal scans a frame time, described analog-digital converter extracts described first threshold information of voltage and Second Threshold information of voltage from bias current line and is stored to exterior storage;

Scan the light-emitting mode of another frame time in described sweep signal under, at described data input phase, after the half-tone information that bus provides by described totalizer carries out superposing formation one digital signal with the described first threshold information of voltage in exterior storage and Second Threshold voltage, and export bias current line to by the driving voltage that digital signal to be converted to analog signal form by described digital analog converter, described driving voltage as described transistor seconds, the reference voltage that comprises described first threshold information of voltage, Second Threshold information of voltage and half-tone information; In described glow phase, provide supply voltage to described transistor seconds, make described transistor seconds provide the drive current irrelevant with described first threshold information of voltage and Second Threshold information of voltage for light-emitting component.