Embodiment
Fig. 1 is the schematic diagram of the display device of one embodiment of the invention.As shown in the figure, display device 100 comprises pixel P11~ Pmnand a driver module 110.Pixel P11~ Pmnall can store electric charge, and luminous according to stored electric charge.Driver module 110 upgrades pixel P11~ Pmnstored electric charge, and make pixel P11~ Pmnluminous according to stored electric charge.
During a picture in (frame), driver module 110 has upgraded all pixel P11~ Pmnstored electric charge, and repeatedly put bright pixel P11~ Pmn.Due to pixel P11~ Pmnrepeatedly present brightness, therefore user can't perceive display device 100 glimmers (Flicker) phenomenon.
In the present embodiment, driver module 110 comprises one scan driver (scan driver) 111 and a data driver (data driver) 113.Scanner driver 111 provides sweep signal SsN1~ S-sNngive pixel P11~ Pmn.Data driver 113 provides data-signal SdA1~ SdAmgive pixel P11~ Pmn.In addition, scanner driver 111 and data driver 113 can respectively by metal wire MLh1~ MLhnand MLv1~ MLvm, provide multiple control signal to give pixel P11~ Pmn, in order to upgrade pixel P11~ Pmnstored electric charge, or control pixel P11~ Pmnlighting time.
In other embodiments, control signal can only by scanner driver 111, data driver 113 or other driver (as clock controller TCON; Do not show) provided.In addition, each pixel by single or multiple metal wire, reception control signal.In FIG, pixel P11~ Pmnby metal wire MLh1~ MLhnand MLv1~ MLvm, receive the control signal from scanner driver 111 and data driver 113, but and be not used to limit the present invention.
Fig. 2 A is that one of the display device of one embodiment of the invention may sequential control figure.As shown in the figure, picture period 200 comprises row period RT1~ RTn.Row period RT1~ RTnduring having a programming separately, (programming period) and one lights period (emitting period).During programming, do not put bright pixel P11~ Pmn.Lighting period, some bright pixel P11~ Pmn.By putting bright pixel P in multiple times11~ Pmn, just can avoid the picture generation scintillation that display device 100 presents.In the present embodiment, at the period RT that programmes1~ RTn, the electric charge stored by corresponding row pixel, and all early than lighting period during programming interior during each row.
To arrange period RT1and RT2for example, at the period PT that programmes1, do not put bright pixel P11~ Pmn, and upgrade first row pixel (as P11~ Pm1) stored by electric charge.In the present embodiment, first row pixel P11~ Pm1be couple to the first scan electrode, in order to receive sweep signal SsN1, and according to sweep signal SsN1, the electric charge that renewal itself is stored.Then, period ET is being lighted1, light all pixel P11~ Pmn.Now (light period ET1), first row pixel can be luminous according to the electric charge after renewal, and other row pixel is luminous by the electric charge stored by script.
Then, at the period PT that programmes2, do not put bright pixel P11~ Pmn, and upgrade secondary series pixel (as P12~ Pm2) stored by electric charge.In the present embodiment, secondary series pixel P12~ Pm2be couple to the second scan electrode, in order to receive sweep signal SsN2, and according to sweep signal SsN2, the electric charge that renewal itself is stored.Then, period ET is being lighted2, light all pixel P11~ Pmn.Now, secondary series pixel can be luminous according to the electric charge after renewal, and other row pixel is luminous by the electric charge stored by script.
Therefore, within picture period 200, driver module 110 is by renewable complete all pixel P11~ Pmnstored electric charge.In addition, the present invention does not limit and how to put bright pixel P11~ Pmn.In the present embodiment, be the control signal S provided by driver module 110cN1~ ScNn, light or do not put bright pixel P11~ Pmn.For example, as control signal ScN1~ ScNnfor low level, pixel P11~ Pmnbe not lit.On the contrary, as control signal ScN1~ ScNnfor high level, pixel P11~ Pmnbe lit.
In fig. 2, during each row, only upgrade the electric charge stored by single row pixel, but and be not used to limit the present invention.In another embodiment (as shown in Figure 2 B), the electric charge stored by two row pixels is upgraded during each row.In other embodiments, the pixel that during each row, renewable three row are above.
In fig. 2b, picture period 210 has row period RT1~ RTk.Row period RT1~ RTkduring there are two programmings separately and two light period.Because the manner of execution in during each row is all identical, therefore only to arrange period RT1for example, its motion flow is described.
Row period RT1there is programming period PT1-1, PT1-2and light period ET1-1, ET1-2, wherein programme period PT1-1early than programming period PT1-2, programming period PT1-2early than lighting period ET1-1, light period ET1-1early than lighting period ET1-2.
At the period PT that programmes1-1, sweep signal SsN1for low level.Therefore, first row pixel (P11~ Pm1) stored by electric charge be updated.At the period PT that programmes1-2, sweep signal SsN2for low level.Therefore, secondary series pixel (P12~ Pm2) stored by electric charge be updated.Lighting period ET1-1and ET1-2, control signal ScN1~ ScNnfor high level, therefore pixel P11~ Pmnall be lit.
The present invention does not limit the electric charge how upgraded stored by pixel.In the present embodiment, as sweep signal SsN1~ SsNnone be low level, the just pixel of renewable corresponding row, but and be not used to limit the present invention.In other embodiments, as sweep signal SsN1~ SsNnduring for high level, just renewable corresponding pixel.
Similarly, in the present embodiment, as control signal ScN1~ ScNnduring for high level, can bright pixel be put, and as control signal ScN1~ ScNnduring for low level, do not put bright pixel, but this discloses and is not used to limit the present invention.In other embodiments, can at control signal ScN1~ ScNnduring for high level, do not put bright pixel, and at control signal ScN1~ ScNnduring for low level, some bright pixel.
Fig. 3 is that one of pixel of the present invention may example.For the clear annexation presented between pixel, Fig. 3 presents pixel P11, P21, P-12and P22inside structure.But, due to pixel P11, P21, P-12and P22inside structure all identical, therefore only with pixel P11for example, its operating principle is described.As shown in the figure, pixel P11comprise storage element 310, driver element 320, luminescence unit 330, lighting unit 340 and a linkage unit 350.
Storage element 310 is coupled between node 361 and 362.Node 361, by interrupteur SW 1, receives operating voltage PVDD or data-signal SdA1.The present invention does not limit operating voltage PVDD and data-signal SdA1source.In a possibility embodiment, operating voltage PVDD or data-signal SdA1provided by data driver 113.For example, data driver 113 can by single metal wire (as data line) or two metal wires, transfer operation voltage PVDD or data-signal SdA1give node 361.
In addition, node 361, also by interrupteur SW 2, receives a datum SlV1.The present invention does not also limit datum SlV1source.In a possibility embodiment, datum SlV1provided by data driver 113.In the present embodiment, storage element 310 is a capacitor, but and is not used to limit the present invention.Any element storing electric charge all can be used as storage element 310.
The electric charge of driver element 320 stored by storage element 310, produces a drive current I11, wherein drive current I11be not subject to the impact of the critical voltage (threshold voltage) of driver element 320.In the present embodiment, driver element 320 is a P-type crystal pipe T1, its grid couple nodes 362, and its source electrode receives an operating voltage PVDD, and its drain electrode couples lighting unit 340.
Luminescence unit 330 is according to drive current I11and it is luminous.The present invention does not limit the kind of luminescence unit 330.In a possibility embodiment, luminescence unit 330 is an Organic Light Emitting Diode (Organic LightEmitting Diode; OLED).
Lighting unit 340 is in order to provide drive current I11give luminescence unit 330.In the present embodiment, lighting unit 340 is a N-type transistor T3.The grid of transistor T3 receives one and lights signal SeM1, the drain electrode of its drain electrode coupling transistors T1, its source electrode couples luminescence unit 330.The present invention does not limit and lights signal SeM1source.In a possibility embodiment, light signal SeM1provided by scanner driver 111.In other embodiments, lighting unit 340 can be a P-type crystal pipe.Because the those skilled in the art that are replaced into of N-type and P-type crystal pipe known very well, therefore repeat no more.
Linkage unit 350 connects (diode connection) in order to make driver element 320 form a diode.In the present embodiment, linkage unit 350 is a P-type crystal pipe T2, and its grid receives one scan signal SsN1, its source electrode couple nodes 362, the drain electrode of its drain electrode coupling transistors T1.In other embodiments, linkage unit 350 can be a N-type transistor.
Driver module 110 by the level of Controlling vertex 361 and 362, can make drive current I11the impact of the critical voltage of transistor T1 can not be subject to.In the present embodiment, driver module 110 is by sweep signal SsN1, light signal SeM1, datum SlV1, data-signal SdA1and switching signal SsW, conducting or off transistor T1 ~ T3, and then the level reaching Controlling vertex 361 and 362.The control mode of driver module 110 will be described below.
First, driver module 110 makes the level of node 361 equal operating voltage PVDD, and by sweep signal SsN1and light signal SeM1, turn-on transistor T2 and T3.(please refer to Fig. 4) in the present embodiment, programming period PT1to have between replacement period 411 and a write detection period 412.
Resetting period 411, switching signal S-sWfor low level, therefore can actuating switch SW1.Now, the level V of node 361361equal operating voltage PVDD.During this period, sweep signal SsN1and light signal SeM1be respectively low level and high level.Therefore, transistor T2 and T3 is switched on.Now, node 362 equals a low level.
Write detection period between 412, driver module 110 provides a data-signal SdA1give node 361, and by sweep signal SsN1and light signal SeM1, turn-on transistor T2 and off transistor T3.In the present embodiment, due to switching signal SsWbe still low level, therefore actuating switch SW1.Now, node 361 receives data-signal SdA1.During this period, sweep signal SsN1and light signal SeM1be low level.Therefore, transistor T2 is switched on, and transistor T3 is not switched on.
Because transistor T2 is switched on, therefore together with the grid of transistor T1 is coupled in drain electrode.Therefore, transistor T1 forms a diode and connects, and the level of node 362 equals the sum total (PVDD+Vth) of the critical voltage Vth of operating voltage PVDD and transistor T1.
Lighting period ET1, driver module 110 provides a datum SlV1give node 361, and by sweep signal SsN1and light signal SeM1, off transistor T2 turn-on transistor T3.In the present embodiment, switching signal SsWfor high level, therefore can actuating switch SW2, in order to reference to level SlV1be sent to node 361.Now, sweep signal SsN1and light signal SeM1be high level.Therefore, transistor T2 is not switched on, and transistor T3 is switched on.
Because transistor T3 is switched on, therefore can by drive current I11be sent to luminescence unit 330, in order to light luminescence unit 330.Drive current I11generation formula as follows:
I11＝Kn*(VGS-Vth)2.................................(1)
Wherein, Kn is the parameter of transistor T1, VgSfor the pressure reduction between the grid of transistor T1 and source electrode, Vth is the critical voltage of transistor T1.
Lighting period ET1, because the level of node 361 is by data-signal SdA1be changed to datum SlV1, therefore the level of node 362 is PVDD+Vth+SlV1-SdA1.Pressure reduction between the grid of transistor T1 and source electrode is brought into formula (1), just can obtain following formula:
I11＝Kn*(PVDD+Vth+SLV1-SDA1-PVDD-Vth)2......(2)
Can following formula be obtained after abbreviation:
I11＝Kn*(SLV1-SDA1)2.......................................(3)
From formula (3), drive current I11the impact of the critical voltage of transistor T1 can not be subject to.Therefore, when the critical voltage of the transistor T1 in each pixel is uneven, uneven critical voltage can't affect the brightness of each luminescence unit.
Fig. 5 is another possibility embodiment of pixel of the present invention.Due to pixel P11~ Pmninternal circuit configuration all identical, therefore only with pixel P11for example.As shown in the figure, pixel P11comprise storage element 510, driver element 520, luminescence unit 530, reset cell 540 and a switch unit 550.
Storage element 510 is coupled between node 561 and 562.The electric charge of driver element 520 stored by storage element 510, produces a drive current I500.In the present embodiment, driver element 520 is a P-type crystal pipe 521, its grid couple nodes 562, and its source electrode receives operating voltage PVDD, and its drain electrode couples luminescence unit 530.In the present embodiment, drive current I500be not subject to the impact of the critical voltage of driver element 520.
Luminescence unit 530 is according to drive current I500and luminous, and and driver element 520 be series between operating voltage PVDD and PVEE.Reset cell 540 is in order to discharge to node 562.In the present embodiment, reset cell 540 is a N-type transistor 541, and its grid receives a reset signal SrES1, its drain electrode one resets level SlV-RES1, its source electrode couple nodes 562.The present invention does not limit reset signal SrES1with replacement level SlV-RES1source.In a possibility embodiment, reset signal SrES1thered is provided by scanner driver 111, and reset level SlV-RES1thered is provided by data driver 113.
Switch unit 550 couple nodes 562 and driver element 520.In the present embodiment, switch unit 550 is a P-type crystal pipe 551, and its grid receives one scan signal SsN1, its source electrode couple nodes 562, the drain electrode of its drain electrode coupling transistors 521.
In the present embodiment, driver module 110 is by operating voltage PVDD, PVEE, sweep signal SsN1, reset signal SrES1, data-signal SdA1and reset level SlV-RES1, the level of Controlling vertex 561 and 562, and then make drive current I500the impact of the critical voltage of driver element 520 can not be subject to.The control method of driver module 110 will be described below.
Please refer to Fig. 6, at the period PT that programmes1interior one resets address period 611, and driver module 110 provides a data-signal SdA1give node 561, and by reset signal SrES1, turn-on transistor 541.In the present embodiment, reset signal SrES1for high level, therefore can turn-on transistor 541.Therefore, the level of node 562 equals to reset level SlV-RES1.
In the present embodiment, sweep signal SsN1for low level, therefore turn-on transistor 551.In other embodiments, in replacement address period 611, sweep signal SsN1can be high level, in order to off transistor 551.Because operating voltage PVEE is high level, therefore do not light luminescence unit 530.
Between detection period 612, node 561 is maintained at data-signal SdA1level, and by reset signal SrES1and sweep signal SsN1, off transistor 541 and turn-on transistor 551.In the present embodiment, reset signal SrES1for low level, therefore, transistor 541 is not switched on.Due to sweep signal SsN1for low level, therefore can turn-on transistor 551.
Because transistor 551 is switched on, therefore transistor 521 is a diode connection.Therefore, the level of node 562 equals the critical voltage Vth sum (i.e. PVDD+Vth) of operating voltage PVDD and transistor 521.Now, because operating voltage PVEE is high level, therefore luminescence unit 530 is not lit.
Lighting period ET1, driver module 110 provides a datum SlV1give node 561, and by reset signal SrES1and sweep signal SsN1, off transistor 541 and 551.Because the level of node 561 is by SdA1be changed to SlV1, therefore, the level of node 562 equals PVDD+Vth+SlV1-SdA1.
The present invention does not limit datum SlV1source.May in embodiment one, the data driver 113 in driver module 110 by single metal wire, during difference, data signal SdA1or datum SlV1give node 561.
In the present embodiment, due to sweep signal SsN1and reset signal SrES1be respectively high level and low level, therefore, off transistor 541 and 551.Now, because operating voltage PVEE is low level, therefore luminescence unit 530 can be lighted.
Level due to node 562 is PVDD+Vth+SlV1-SdA1, therefore, when transistor 521 produces drive current I according to above formula (1)500when giving luminescence unit 530, the drive current I that it produces500the impact of the critical voltage of transistor 521 can't be subject to.
During a picture, repeatedly light or do not light all pixels, therefore scintillation user can being avoided to perceive display device occur.In addition, during not putting bright pixel (during programming), upgrade the electric charge stored by least one row pixel, just can guarantee that display device presents correct picture.
Moreover, by the dot structure of Fig. 3 and Fig. 5, the impact that the uneven critical voltage of the driver element in pixel causes can be avoided.Therefore, when providing identical data-signal to give pixel, pixel can present identical brightness.
Unless otherwise defined, the general understanding of persond having ordinary knowledge in the technical field of the present invention is all belonged to (comprising technology and scientific terms) at this all vocabulary.In addition, unless clear expression, it is consistent that the definition of vocabulary in general dictionary should be interpreted as meaning in the article with its correlative technology field, and should not be construed as perfect condition or too formal voice.
Although the present invention discloses as above with preferred embodiment; so itself and be not used to limit the present invention, those skilled in the art, under the premise without departing from the spirit and scope of the present invention; can do some changes and retouching, therefore protection scope of the present invention is as the criterion with claim of the present invention.