KR101367000B1 - Organic Light Emitting Display - Google Patents

Abstract

According to the present invention, the first, second and third switching transistors which are turned on in the same manner by the first scan signal supplied from the first scan wiring and the fourth which are turned on by the second scan signal supplied from the second scan wiring are provided. First and second driving transistors in which a threshold voltage is simultaneously programmed by the data signal when the switching transistor, the first, second and third switching transistors are turned on and a data signal is supplied from the data wiring. A subpixel including a capacitor supplying the same data voltage to the transistor, and an organic light emitting diode emitting light when the first driving transistor is turned on and the fourth switching transistor is turned on; A scan driver configured to supply first and second scan signals to the first and second scan wirings; And a data driver for supplying a data signal to the data line.

OLED display, current, mirror

Description

[0001] The present invention relates to an organic light emitting display,

The present invention relates to an organic light emitting display.

An organic light emitting display device used in an organic light emitting display device is a self-light emitting device having a light emitting layer formed between two electrodes positioned on a substrate.

In addition, the organic light emitting display device may include a top emission type, a bottom emission type, or a dual emission type depending on a direction in which light is emitted. It is divided into a passive matrix and an active matrix depending on the driving method.

In the organic light emitting display device, when a scan signal, a data signal, and a power are supplied to a plurality of subpixels arranged in a matrix form, the selected subpixels emit light to display an image.

On the other hand, the driving method of the organic light emitting display device can be largely divided into voltage type and current type. Here, in the case of the voltage type, there is an advantage that the supply delay time of the data signal by the parasitic capacitor of the panel is shorter than the current type. However, the voltage type has a disadvantage in that the compensation degree is smaller than that of the current type when the compensation circuit is embedded in the subpixel.

On the other hand, in the case of the current type, the compensation is possible even without a complicated compensation circuit, and the degree of compensation is larger than that of the current type. However, since the current is supplied as much as the data signal, there is a disadvantage in that a large delay time is required to supply the data signal.

Therefore, in the case of the current type, in order to overcome this disadvantage, a transistor mirror circuit using a scale down technique is used. If two transistors arranged in a mirror form are not matched, an incorrect data signal is supplied as much as the size thereof. There are drawbacks and improvements are required.

SUMMARY OF THE INVENTION An object of the present invention is to provide a current-driven organic light emitting display device capable of simultaneously programming a threshold voltage such that there is no variation in threshold voltage and current mobility.

According to the above-described problem solving means, the present invention provides the first, second and third switching transistors that are turned on in the same manner by the first scan signal supplied from the first scan wiring, and the second scan signal supplied from the second scan wiring. A fourth switching transistor turned on by the first switching transistor, the first and second driving transistors whose threshold voltages are simultaneously programmed by the data signal when the first, second and third switching transistors are turned on and the data signal is supplied from the data wiring; A subpixel including a capacitor supplying the same data voltage to the first and second driving transistors, and an organic light emitting diode emitting light when the first driving transistor is turned on and the fourth switching transistor is turned on; A scan driver configured to supply first and second scan signals to the first and second scan wirings; And a data driver for supplying a data signal to the data line.

The first and second driving transistors may be mirror transistors having the same size.

The scan driver supplies a first scan signal to the first scan wiring so that the first and second driving transistors are programmed at the same time, and the fourth switching transistor is turned off in a period where the first, second and third switching transistors are turned on. The second scan signal can be supplied to the second scan wiring as much as possible.

The subpixel includes a first switching transistor having one end connected to the data line and a gate connected to the first scan line, a second switching transistor connected to a gate of the first scan line and one end connected to the data line, and the first scan line. A third switching transistor having a gate connected to the data line and having one end connected to the data line, a fourth switching transistor having a gate connected to the second scan line and having one end connected to the other end of the third switching transistor and a gate connected to the other end of the first switching transistor. Is connected to one end of the third switching transistor and one end is connected to the other end of the third switching transistor, and the other end of the first power supply wiring is connected to the gate of the other end of the first switching transistor and the other end of the second switching transistor is connected. A second driving transistor having the other end connected to the first power supply wiring, and one end connected to the first power supply wiring; And the other end connected to a common capacitor to the gate of the transistor, a first electrode being connected to the other terminal of the fourth switching transistor may comprise an organic light emitting diode a second electrode connected to a second power supply wiring.

The subpixel includes a first switching transistor having one end connected to the data line and a gate connected to the first scan line, a second switching transistor connected to a gate of the first scan line and one end connected to the data line, and the first scan line. A third switching transistor having a gate connected to the other end of the second switching transistor, a fourth switching transistor having a gate connected to the second scan wiring, and one end connected to the other end of the third switching transistor, and a first switching transistor A first driving transistor having a gate connected to the other end of the transistor, one end connected to the other end of the third switching transistor, and the other end connected to the first power supply wiring, a gate connected to the other end of the first switching transistor, and the other end of the second switching transistor. A second driving transistor having one end connected to the first power line and the other end connected to the first power line, and one end connected to the first power line And an organic light emitting diode having a second end connected to the gates of the first and second driving transistors in common, and an organic light emitting diode connected to the second end of the fourth switching transistor and the second electrode connected to the second power line. .

The subpixel may include a first switching transistor having one end connected to a data line and a gate connected to the first scan line, a second switching transistor having a gate connected to the first scan line and one end connected to the other end of the first switching transistor; A third switching transistor having a gate connected to the first scan wire and having one end connected to the other end of the second switching transistor, a fourth switching transistor having a gate connected to the second scan wire and having one end connected to the other end of the third switching transistor; A first driving transistor having a gate connected to the other end of the second switching transistor, one end connected to the other end of the third switching transistor, and the other end connected to the first power supply wiring, and a gate connected to the other end of the second switching transistor connected to the first switching. A second driving transistor having one end connected to the other end of the transistor and the other end connected to the first power line, and a first power supply An organic light emitting diode having one end connected to the gate of the first and second driving transistors, the other end of which is commonly connected to the gate of the first and second driving transistors, and a first electrode connected to the other end of the fourth switching transistor and a second electrode connected to the second power line. It may include.

The subpixel may include a first switching transistor having one end connected to the data line and a gate connected to the first scan line, a second switching transistor having a gate connected to the first scan line and one end connected to the other end of the first switching transistor. A third switching transistor having a gate connected to the first scan line and having one end connected to the other end of the second switching transistor, a fourth switching transistor having a gate connected to the second scan line and having one end connected to the other end of the third switching transistor; A first driving transistor having a gate connected to the other end of the first switching transistor, one end connected to the other end of the third switching transistor, and the other end connected to the first power supply wiring, and a gate connected to the other end of the first switching transistor; A second driving transistor having one end connected to the other end of the switching transistor and the other end connected to the first power line; An organic light emitting diode having one end connected to a line and a second end connected to the gate of the first and second driving transistors in common; a first electrode connected to the other end of the fourth switching transistor and a second electrode connected to the second power line; It may include.

The subpixel may include a first switching transistor having one end connected to a data line and a gate connected to the first scan line, a second switching transistor having a gate connected to the first scan line and one end connected to the other end of the first switching transistor; A third switching transistor having a gate connected to the first scan wiring and having one end connected to the other end of the first switching transistor, a fourth switching transistor having a gate connected to the second scan wiring and having one end connected to the other end of the third switching transistor; A first driving transistor having a gate connected to the other end of the first switching transistor, one end connected to the other end of the third switching transistor, and the other end connected to the first power supply wiring, a gate connected to the other end of the first switching transistor, and a second switching A second driving transistor having one end connected to the other end of the transistor and the other end connected to the first power line, and a first power supply An organic light emitting diode having one end connected to a line and a second end connected to the gate of the first and second driving transistors in common; a first electrode connected to the other end of the fourth switching transistor and a second electrode connected to the second power line; It may include.

The subpixel includes a first switching transistor having one end connected to the data line and a gate connected to the first scan line, a second switching transistor connected to a gate of the first scan line and one end connected to the data line, and the first scan line. A third switching transistor having a gate connected to the other end of the second switching transistor, a fourth switching transistor having a gate connected to the second scan wiring, and one end connected to the other end of the third switching transistor, and a first switching transistor A first driving transistor having a gate connected to the other end of the second switching transistor and one end connected to the other end of the third switching transistor, and the other end connected to the first power supply wiring, a gate connected to the other end of the first switching transistor, and connected to the other end of the second switching transistor. One end is connected to the second driving transistor and the other end is connected to the first power line and one end to the first power line And an organic light emitting diode having a second end connected to the gate of the first and second driving transistors in common and a first electrode connected to the other end of the fourth switching transistor and a second electrode connected to the second power line. .

The transistors included in the sub pixel may be p-type transistors.

The present invention has the effect of providing a current-driven organic light emitting display device capable of simultaneously programming the threshold voltage so that no deviation occurs in the threshold voltage and the current mobility. In addition, the organic light emitting display device can reduce the error caused by mismatch between the mirror transistors, scale down the programming current, and provide a sub pixel structure that can reduce the specific gravity of the transistor in the sub pixel.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a schematic plan view of an organic light emitting display according to an embodiment of the present invention.

As shown in FIG. 1, the organic light emitting display may include a display unit 120 on which a plurality of subpixels P are disposed. The plurality of subpixels P located on the substrate 110 are vulnerable to moisture or oxygen.

Thus, the substrate 110 and the sealing substrate 130 can be sealed by providing the sealing substrate 130 and forming the adhesive member 140 on the outer substrate 110 of the display unit 120. Meanwhile, a plurality of sub-pixels P may be driven by a driving unit 150 positioned on the substrate 110 to display an image.

The driver 150 may include a scan driver to supply the first and second scan signals to the plurality of subpixels P and a data driver to supply a data signal to the plurality of subpixels P. Here, the driving unit 150 is only schematically illustrated that the scan driving unit and the data driving unit are formed as one example, and the scan driving unit and the data driving unit may be separately located on the substrate 110 as described above.

On the other hand, the above-described subpixels may be as follows.

2A is an exemplary cross-sectional view of the subpixel shown in FIG.

As shown in FIG. 2A, a buffer layer 105 is located on a substrate 110. Buffer layer 105 is selectively using, for example, to form to protect the transistor to be formed in a subsequent process from impurities such as alkali ions leaked from the substrate 110, silicon oxide (SiO _2), silicon nitride (SiNx) .

Here, the substrate 110 may be glass, plastic or metal.

The semiconductor layer 111 is located on the buffer layer 105. The semiconductor layer 111 may include amorphous silicon or crystallized polycrystalline silicon.

In addition, the semiconductor layer 111 may include a source region and a drain region including p-type or n-type impurities, and may include a channel region other than the source region and the drain region.

The first insulating layer 115, which may be a gate insulating layer, is positioned on the semiconductor layer 111. The first insulating layer 115 may be a silicon oxide film (SiOx), a silicon nitride film (SiNx), or a multilayer thereof.

The gate electrode 120c may be positioned at a predetermined region of the semiconductor layer 111 positioned on the first insulating layer 115, that is, at a position corresponding to the channel region when impurities are injected. The scan line 120a and the capacitor lower electrode 120b may be positioned on the same layer as the gate electrode 120c.

The gate electrode 120c is formed of a material selected from the group consisting of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper One or an alloy thereof.

The gate electrode 120c may be formed of a material selected from the group consisting of Mo, Al, Cr, Au, Ti, Ni, Ne, Or an alloy of any one selected from the above.

Further, the gate electrode 120c may be a double layer of molybdenum / aluminum-neodymium or molybdenum / aluminum.

The scan line 120a may be formed of a material selected from the group consisting of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper One or an alloy thereof. The scan line 120a may be formed of one selected from the group consisting of Mo, Al, Cr, Au, Ti, Ni, Ne, Or an alloy of any one selected from the above. Further, the scan line 120a may be a double layer of molybdenum / aluminum-neodymium or molybdenum / aluminum.

The second insulating layer 125 serving as the interlayer insulating layer 125 is positioned on the substrate 110 including the scan wiring 120a, the capacitor lower electrode 120b, and the gate electrode 120c. The second insulating layer 125 may be a silicon oxide film (SiOx), a silicon nitride film (SiNx), or a multilayer thereof.

Contact holes 130b and 130c exposing portions of the semiconductor layer 111 are disposed in the second insulating layer 125 and the first insulating layer 115.

Drain and source electrodes 140c and 140d electrically connected to the semiconductor layer 111 through contact holes 130b and 130c penetrating through the second insulating film 125 and the first insulating film 115 are formed in the pixel region. Located.

The drain electrode and the source electrode 140c and 140d may be formed of a single layer or multiple layers and may be formed of a single layer of molybdenum (Mo), aluminum (Al), chromium (Cr) , Gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu). When the drain electrode and the source electrodes 140c and 140d are multi-layered, a triple layer of molybdenum / aluminum-neodymium, molybdenum / aluminum / molybdenum or molybdenum / aluminum-neodymium / molybdenum may be used.

The data line 140a, the capacitor upper electrode 140b, and the power supply line 140e may be positioned on the same layer as the drain electrode and the source electrodes 140c and 140d.

The data wiring 140a and the power supply wiring 140e located in the non-pixel region may be formed of a single layer or multiple layers. When the data wiring 140a and the power wiring 140e are single layers, the data wiring 140a and the power wiring 140e may be made of molybdenum And may be made of any one selected from the group consisting of Al, Cr, Au, Ti, Ni, Ne, and Cu.

When the data wiring 140a and the power wiring 140e are multilayered, they may be formed of a triple layer of molybdenum / aluminum-neodymium, molybdenum / aluminum / molybdenum or molybdenum / aluminum-neodymium / molybdenum.

In addition, the data wiring 140a and the power wiring 140e may be formed of a triple layer of molybdenum / aluminum-neodymium / molybdenum.

The third insulating layer 145 is positioned on the data line 140a, the capacitor upper electrode 140b, the drain and source electrodes 140c and 140d, and the power line line 140e. The third insulating layer 145 may be a planarization layer for alleviating the step difference of the lower structure, and may be formed of organic materials such as polyimide, benzocyclobutene series resin, acrylate, or silicon oxide. It may be formed of an inorganic material such as spin on glass (SOG), which is coated in the form and then cured.

Alternatively, the third insulating layer 145 may be a passivation layer, and may be a silicon nitride layer (SiNx), a silicon oxide layer (SiOx), or a multilayer thereof.

A via hole 165 exposing one of the drain and source electrodes 140c and 140d is disposed in the third insulating layer 145, and the drain and source electrode 140c is disposed on the third insulating layer 145 through the via hole 165. , The first electrode 160 is electrically connected to any one of 140d.

The first electrode 160 may be an anode, and may be a transparent electrode or a reflective electrode. Herein, when the structure of the organic light emitting display device is a backside or double-sided light emission, the first electrode 160 may be a transparent electrode, and among indium tin oxide (ITO), indium zinc oxide (IZO), or zinc oxide (ZnO) It can be either.

In addition, the first electrode 160 may be a reflective electrode when the structure of the organic light emitting display device is a front emission type, and aluminum (Al), silver (Ag), or the like may be formed under the layer of any one of ITO, IZO, Nickel (Ni), and in addition, a reflective layer may be included between two layers of any one of ITO, IZO, and ZnO.

A fourth insulating layer 155 is disposed on the first electrode 160 to insulate the first electrodes adjacent to the first electrode 160 and include an opening 175 for exposing a portion of the first electrode 160. The light emitting layer 170 is located on the first electrode 160 exposed by the opening 175.

The second electrode 180 is located on the light emitting layer 170. The second electrode 180 may be a cathode electrode and may be made of magnesium (Mg), calcium (Ca), aluminum (Al), silver (Ag), or an alloy thereof having a low work function.

Here, the second electrode 180 may be formed to have a thickness thin enough to transmit light when the organic light emitting display device has a front or both-side light emitting structure, and when the organic light emitting display device has a back light emitting structure, It can be formed thick enough to reflect light.

The above-described embodiments are based on a total of seven masks, namely, a semiconductor layer, a gate electrode (including a scan wiring and a capacitor lower electrode), contact holes, a source electrode and a drain electrode (including a data wiring, a power supply wiring, , The first electrode and the opening are formed by using a mask.

Hereinafter, an embodiment in which an organic electroluminescent display device is formed using a total of five masks is disclosed. The description of the parts overlapping with those described above in the embodiments described below will be omitted.

2B is another cross-sectional exemplary view of the subpixel shown in FIG.

2B, the buffer layer 105 is located on the substrate 110, and the semiconductor layer 111 is located on the buffer layer 105. [ The first insulating layer 115 is disposed on the semiconductor layer 111, and the gate electrode 120c, the capacitor lower electrode 120b, and the scan wiring 120a are positioned on the first insulating layer 115. And the second insulating film 125 is located on the gate electrode 120c.

The first electrode 160 is positioned on the second insulating layer 125, and contact holes 130b and 130c exposing the semiconductor layer 111 are positioned. The first electrode 160 and the contact holes 130b and 130c may be formed at the same time.

The source electrode 140d, the drain electrode 140c, the data line 140a, the capacitor upper electrode 140b, and the power source line 140e are positioned on the second insulating layer 125. Here, a part of the drain electrode 140c may be located on the first electrode 160. [

The third insulating layer 145, which may be a pixel definition layer or a bank layer, is positioned on the substrate 110 on which the above-described structure is formed, and the opening 175 exposing the first electrode 160 is positioned in the third insulating layer 145. do. The light emitting layer 170 is located on the first electrode 160 exposed by the opening 175 and the second electrode 180 is located on the light emitting layer 170.

As described above, a total of five masks, that is, a semiconductor layer, a gate electrode (including a scan wiring and a capacitor lower electrode), a first electrode (including a contact hole), a source / drain electrode (data wiring, a power wiring, and a capacitor upper electrode are included) ) And an organic light emitting display device using a mask in the process of forming an opening has the advantage of reducing the number of masks, thereby reducing manufacturing costs and increasing the efficiency of mass production.

Such an organic light emitting display device may have various methods for implementing a color image. A method of implementing the organic light emitting display will be described with reference to FIGS. 3A to 3B.

3A to 3B illustrate embodiments of implementing a color image in an organic light emitting display device according to an embodiment of the present invention.

3A, the color image forming method shown in FIG. 3A includes a red color emitting layer 170R, a green color light emitting layer 170G, and a blue color light emitting layer 170B separately emitting red, green, and blue light, And shows an image implementation method.

As shown in FIG. 3A, red light, green light, and blue light are provided from the respective light emitting layers 170R, 170G, and 170B, respectively, so that red light / green light / blue light are mixed to display a color image.

Here, an electron transport layer (ETL), a hole transport layer (HTL), and the like may be further included at the top and bottom of each of the emission layers 170R, 170G, and 170B.

In addition, the color image implementation method illustrated in FIG. 3B is a color image implementation method of an organic light emitting display device including a white emission layer 270W, a red color filter 290R, a green color filter 290G, and a blue color filter 290B. It is shown.

The white light provided from the white light emitting layer 270W is transmitted through the red color filter 290R, the green color filter 290G and the blue color filter 290B while the red light / green light / Respectively, so that a color image can be displayed.

Here, the upper and lower portions of each white light emitting layer 270W may further include an electron transport layer (ETL), a hole transport layer (HTL), and the like, and the arrangement and structure thereof may be variously modified.

Here, the bottom emission structure is shown and described in FIGS. 3A and 3B, but the present invention is not limited thereto, and various modifications can be made to the arrangement and structure of the top emission structure.

In addition, although two types of driving methods have been shown and described with respect to the color image realizing method, the present invention is not limited thereto, and various modifications are possible as needed.

4 is a hierarchical structure diagram of an organic light emitting diode according to an embodiment of the present invention.

Referring to FIG. 4, an organic light emitting diode according to an exemplary embodiment of the present invention includes a substrate 110, a first electrode 160 disposed on the substrate 110, a first electrode 160 disposed on the first electrode 160, A second electrode 180 located on the hole injection layer 171, the hole transport layer 172, the light emitting layer 170, the electron transport layer 173, the electron injection layer 174 and the electron injection layer 174 .

First, a hole injection layer 171 is formed on the first electrode 160. The hole injection layer 171 may function to smoothly inject holes from the first electrode 160 into the light emitting layer 170 and may be formed of at least one selected from the group consisting of CuPc (cupper phthalocyanine), PEDOT (poly (3,4) -ethylenedioxythiophene ), PANI (polyaniline) and NPD (N, N-dinaphthyl-N, N'-diphenyl benzidine).

The hole injection layer 171 described above can be formed by an evaporation method or a spin coating method.

The hole transport layer 172 plays a role of facilitating the transport of holes and may be formed by using NPD (N, N-dinaphthyl-N, N'-diphenyl benzidine), TPD (N, N'- , N'-bis- (phenyl) -benzidine), s-TAD and MTDATA (4,4 ', 4 "-tris (N-3-methylphenyl-N-phenylamino) But is not limited thereto.

The hole transport layer 172 can be formed by evaporation or spin coating. The light emitting layer 170 described above may be formed of a material that emits red, green, blue, and white light, and may be formed using phosphorescent or fluorescent materials.

When the light emitting layer 170 is red, it includes a host material containing carbazole biphenyl (CBP) or mCP (1,3-bis (carbazol-9-yl) wherein the dopant comprises at least one selected from the group consisting of iridium, iridium, PQIr (acac) (bis (1-phenylquinoline) acetylacetonate iridium), PQIr (tris (1-phenylquinoline) iridium) and PtOEP (octaethylporphyrin platinum) Or PBD: Eu (DBM) 3 (Phen) or Perylene. However, the present invention is not limited thereto.

When the light emitting layer 170 is green, it may be made of a phosphorescent material including a dopant material including a host material including CBP or mCP and containing Ir (ppy) 3 (fac tris (2-phenylpyridine) iridium) Alternatively, it may be made of a fluorescent material including Alq3 (tris (8-hydroxyquinolino) aluminum), but is not limited thereto.

When the light emitting layer 170 is blue, it may include a phosphorescent material including a dopant material including (4,6-F2ppy) 2Irpic including a host material including CBP or mCP.

Alternatively, the fluorescent material may include any one selected from the group consisting of spiro-DPVBi, spiro-6P, distyrylbenzene (DSB), distyrylarylene (DSA), PFO polymer, and PPV polymer. It is not limited.

Here, the electron transport layer 173 serves to smooth the transport of electrons, and may be any one or more selected from the group consisting of Alq3 (tris (8-hydroxyquinolino) aluminum), PBD, TAZ, spiro-PBD, BAlq and SAlq But is not limited thereto.

The electron transporting layer 173 can be formed by an evaporation method or a spin coating method. The electron transport layer 173 may also prevent holes injected from the first electrode from passing through the light emitting layer to the second electrode. That is, it may serve as a hole blocking layer and may serve to efficiently combine holes and electrons in the light emitting layer.

Here, the electron injection layer 174 serves to smooth the injection of electrons, and may use Alq3 (tris (8-hydroxyquinolino) aluminum), PBD, TAZ, spiro-PBD, BAlq or SAlq .

The electron injection layer 174 may be formed by vacuum evaporation of organic and inorganic materials forming the electron injection layer.

Here, the hole injection layer 171 or the electron injection layer 174 may further include an inorganic material, and the inorganic material may further include a metal compound. The metal compound may include an alkali metal or an alkaline earth metal. Metal compound including an alkali metal or alkaline earth metal LiQ, LiF, NaF, KF, RbF, CsF, FrF, BeF 2, MgF 2, CaF 2, SrF 2, BaF any one selected from the group consisting of ₂ and RaF ₂ or more But is not limited thereto.

That is, the inorganic material in the electron injection layer 174 facilitates hopping of electrons injected from the second electrode 180 into the light emitting layer 170, thereby balancing the holes and electrons injected into the light emitting layer, Can be improved.

The inorganic material in the hole injection layer 171 reduces the mobility of holes injected from the first electrode 160 into the light emitting layer 170 so as to balance the holes and electrons injected into the light emitting layer 170, .

Here, the present invention is not limited to FIG. 4, and at least one of the electron injection layer 174, the electron transport layer 173, the hole transport layer 172, and the hole injection layer 171 may be omitted.

Meanwhile, the subpixels disposed in the display panel of the organic light emitting display device according to the present invention may include first, second and third switching transistors which are turned on by the first scan signal supplied from the first scan wiring. Can be. The second switching transistor may further include a fourth switching transistor turned on by the second scan signal supplied from the second scan wiring. In addition, when the first, second, and third switching transistors are turned on and a data signal is supplied from the data line, the first, second, and third switching transistors may include first and second driving transistors simultaneously programmed by the data signal. In addition, the electronic device may include a capacitor supplying the same data voltage to the first and second driving transistors. The organic light emitting diode may include an organic light emitting diode that emits light when the first driving transistor is turned on and the fourth switching transistor is turned on.

Meanwhile, the first and second driving transistors described above may be mirror transistors having the same size. In addition, the transistors included in the subpixel may be p-type.

Here, the scan driver supplies a first scan signal to the first scan wiring so that the first and second driving transistors can be programmed simultaneously, and the fourth switching transistor is provided in a section in which the first, second and third switching transistors are turned on. The second scan signal may be supplied to the second scan line to be turned off.

In the above description, the sub pixel circuit may be configured as follows.

5 is a circuit diagram illustrating a subpixel according to a first embodiment of the present invention.

As illustrated in FIG. 5, the subpixel may include a first switching transistor T1 having one end connected to the data line Data and a gate connected to the first scan line Scan1. In addition, the second switching transistor T2 may include a gate connected to the first scan line Scan1 and one end connected to the data line Data. In addition, a third switching transistor T3 may include a gate connected to the first scan line Scan1 and one end connected to the data line Data. In addition, a fourth switching transistor T4 may include a gate connected to the second scan line Scan2 and one end connected to the other end of the third switching transistor T3. Also, a first driving transistor D1 having a gate connected to the other end of the first switching transistor T1, one end connected to the other end of the third switching transistor T3, and the other end connected to the first power supply line VDD. can do. Also, a second driving transistor D2 having a gate connected to the other end of the first switching transistor T1, one end connected to the other end of the second switching transistor T2, and the other end connected to the first power line VDD is included. can do. The capacitor C may include a capacitor C having one end connected to the first power line VDD and the other end connected to the gates of the first and second driving transistors D1 and D2 in common. The organic light emitting diode OLED may further include an organic light emitting diode OLED having a first electrode connected to the other end of the fourth switching transistor T4 and a second electrode connected to the second power line VSS.

In the sub-pixel circuit as described above, threshold voltages of the first and second driving transistors are programmed simultaneously by the driving waveform shown in FIG. 6, and the first driving transistor D1 is turned on by the data voltage stored in the capacitor, and the fourth driving transistor D1 is turned on. When the switching transistor T4 is turned on, the organic light emitting diode OLED may emit light.

FIG. 6 is a driving waveform diagram schematically illustrating a method of driving the subpixel illustrated in FIG. 5. See FIG. 5 together to help understand the description.

5 and 6, the scan driver can supply the first and second scan signals Scan1 and Scan2 to the subpixel during the scan time period, and the data driver can supply the data signal to the subpixel. have.

The scan driver supplies a logic low signal to the first scan signal Scan1 to turn on the first to third switching transistors T1 .. T3 that are p-type transistors, and the second scan signal Scan2. The fourth switching transistor T4, which is a p-type transistor, may be turned off by supplying a low logic high signal.

In this period, the threshold voltages of the first and second driving transistors D1 and D2, which are mirror transistors, are turned on through the turned-on first to third switching transistors T1..T3, so that the first driving transistor is programmed under the same condition. The phenomenon in which mismatch between D1 and the second driving transistor D2 occurs can be eliminated.

In this state, the organic light emitting diode OLED may be in a state where no current flows because the first driving transistor D1 and the fourth switching transistor T4 are turned off. The capacitor C is supplied to the data line Data at the same time as programming of the first and second driving transistors D1 and D2 is completed through the turned-on first to third switching transistors T1 .. T3. The data signal can be charged with a data voltage.

Next, the scan driver may supply the first and second scan signals Scan1 and Scan2 to the subpixel during the frame time period.

The scan driver supplies a logic high signal to the first scan signal Scan1 to turn off the first to third switching transistors T1..T3 that are p-type transistors, and the second scan signal Scan2. The fourth switching transistor T4, which is a p-type transistor, may be turned on by supplying a logic low signal.

In this period, when the first driving transistor D1 is driven by the data voltage of the discharged capacitor C, current may flow through the turned-on fourth switching transistor T4.

In this state, the organic light emitting diode OLED may receive light as long as the gate of the first driving transistor D1 is opened.

On the other hand, by repeatedly occurring in each sub-pixel in such a series of driving method, the display panel can implement a desired image.

Hereinafter, the second to sixth embodiments illustrated in FIGS. 7 to 11 are also driven by the same driving method as described with reference to FIG. 6, but the circuit configuration of the subpixel may be configured in other forms.

Hereinafter, the second to sixth embodiments will be described with reference to the drawings, but the driving method uses the same method as described above with reference to FIG. 6, and thus description thereof will be omitted.

7 is a circuit diagram illustrating a subpixel according to a second embodiment of the present invention.

As illustrated in FIG. 7, the subpixel may include a first switching transistor T1 having one end connected to the data line Data and a gate connected to the first scan line Scan1. In addition, the second switching transistor T2 may include a gate connected to the first scan line Scan1 and one end connected to the data line Data. In addition, a third switching transistor T3 may include a gate connected to the first scan line Scan1 and one end connected to the other end of the second switching transistor T2. In addition, a fourth switching transistor T4 may include a gate connected to the second scan line Scan2 and one end connected to the other end of the third switching transistor T3. Also, a first driving transistor D1 having a gate connected to the other end of the first switching transistor T1, one end connected to the other end of the third switching transistor T3, and the other end connected to the first power supply line VDD. can do. Also, a second driving transistor D2 having a gate connected to the other end of the first switching transistor T1, one end connected to the other end of the second switching transistor T2, and the other end connected to the first power line VDD is included. can do. The capacitor C may include a capacitor C having one end connected to the first power line VDD and the other end connected to the gates of the first and second driving transistors D1 and D2 in common. The organic light emitting diode OLED may further include an organic light emitting diode OLED having a first electrode connected to the other end of the fourth switching transistor T4 and a second electrode connected to the second power line VSS.

8 is a circuit diagram illustrating a subpixel according to a third embodiment of the present invention.

As illustrated in FIG. 8, the subpixel may include a first switching transistor T1 having one end connected to the data line Data and a gate connected to the first scan line Scan1. In addition, a second switching transistor T2 may include a gate connected to the first scan line Scan1 and one end connected to the other end of the first switching transistor T1. In addition, a third switching transistor T3 may include a gate connected to the first scan line Scan1 and one end connected to the other end of the second switching transistor T2. In addition, a fourth switching transistor T4 may include a gate connected to the second scan line Scan2 and one end connected to the other end of the third switching transistor T3. Also, a first driving transistor D1 having a gate connected to the other end of the second switching transistor T2, one end connected to the other end of the third switching transistor T3, and the other end connected to the first power line VDD. can do. Also, a second driving transistor D2 having a gate connected to the other end of the second switching transistor T2, one end connected to the other end of the first switching transistor T1, and the other end connected to the first power line VDD is included. can do. The capacitor C may include a capacitor C having one end connected to the first power line VDD and the other end connected to the gates of the first and second driving transistors D1 and D2 in common. The organic light emitting diode OLED may further include an organic light emitting diode OLED having a first electrode connected to the other end of the fourth switching transistor T4 and a second electrode connected to the second power line VSS.

9 is a circuit diagram illustrating a subpixel according to a fourth embodiment of the present invention.

As illustrated in FIG. 9, the subpixel may include a first switching transistor T1 having one end connected to the data line Data and a gate connected to the first scan line Scan1. In addition, a second switching transistor T2 may include a gate connected to the first scan line Scan1 and one end connected to the other end of the first switching transistor T1. In addition, a third switching transistor T3 may include a gate connected to the first scan line Scan1 and one end connected to the other end of the second switching transistor T. In addition, a fourth switching transistor T4 may include a gate connected to the second scan line Scan2 and one end connected to the other end of the third switching transistor T3. Also, a first driving transistor D1 having a gate connected to the other end of the first switching transistor T1, one end connected to the other end of the third switching transistor T3, and the other end connected to the first power supply line VDD. can do. Also, a second driving transistor D2 having a gate connected to the other end of the first switching transistor T1, one end connected to the other end of the second switching transistor T2, and the other end connected to the first power line VDD is included. can do. The capacitor C may include a capacitor C having one end connected to the first power line VDD and the other end connected to the gates of the first and second driving transistors D1 and D2 in common. The organic light emitting diode OLED may further include an organic light emitting diode OLED having a first electrode connected to the other end of the fourth switching transistor T4 and a second electrode connected to the second power line VSS.

10 is a circuit diagram illustrating a subpixel according to a fifth embodiment of the present invention.

As illustrated in FIG. 10, the subpixel may include a first switching transistor T1 having one end connected to the data line Data and a gate connected to the first scan line Scan1. In addition, a second switching transistor T2 may include a gate connected to the first scan line Scan1 and one end connected to the other end of the first switching transistor T1. In addition, a third switching transistor T3 may include a gate connected to the first scan line Scan1 and one end connected to the other end of the first switching transistor T2. In addition, a fourth switching transistor T4 may include a gate connected to the second scan line Scan2 and one end connected to the other end of the third switching transistor T3. Also, a first driving transistor D1 having a gate connected to the other end of the first switching transistor T1, one end connected to the other end of the third switching transistor T3, and the other end connected to the first power supply line VDD. can do. Also, a second driving transistor D2 having a gate connected to the other end of the first switching transistor T1, one end connected to the other end of the second switching transistor T2, and the other end connected to the first power line VDD is included. can do. The capacitor C may include a capacitor C having one end connected to the first power line VDD and the other end connected to the gates of the first and second driving transistors D1 and D2 in common. The organic light emitting diode OLED may further include an organic light emitting diode OLED having a first electrode connected to the other end of the fourth switching transistor T4 and a second electrode connected to the second power line VSS.

11 is a circuit diagram illustrating a subpixel according to a sixth embodiment of the present invention.

As illustrated in FIG. 11, the subpixel may include a first switching transistor T1 having one end connected to the data line Data and a gate connected to the first scan line Scan1. In addition, the second switching transistor T2 may include a gate connected to the first scan line Scan1 and one end connected to the data line Data. In addition, a third switching transistor T3 may include a gate connected to the first scan line Scan1 and one end connected to the other end of the second switching transistor T2. In addition, a fourth switching transistor T4 may include a gate connected to the second scan line Scan2 and one end connected to the other end of the third switching transistor T3. Also, a first driving transistor D1 having a gate connected to the other end of the first switching transistor T1, one end connected to the other end of the third switching transistor T3, and the other end connected to the first power supply line VDD. can do. Also, a second driving transistor D2 having a gate connected to the other end of the first switching transistor T1, one end connected to the other end of the second switching transistor T2, and the other end connected to the first power line VDD is included. can do. The capacitor C may include a capacitor C having one end connected to the first power line VDD and the other end connected to the gates of the first and second driving transistors D1 and D2 in common. The organic light emitting diode OLED may further include an organic light emitting diode OLED having a first electrode connected to the other end of the fourth switching transistor T4 and a second electrode connected to the second power line VSS.

The present invention described in the above embodiments provides a subpixel having mirror transistors having the same size, and provides a current-driven organic light emitting display device capable of simultaneously programming threshold voltages so that no deviation occurs in threshold voltages and current mobility. It is effective to provide. Accordingly, the organic light emitting display device can reduce the error caused by mismatch between the mirror transistors, scale down the programming current, and provide a sub pixel structure that can reduce the specific gravity of the transistor in the sub pixel. .

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, the above-described technical configuration of the present invention may be embodied by those skilled in the art to which the present invention pertains without changing the technical spirit or essential features of the present invention. It will be appreciated that the present invention may be practiced as. Therefore, the embodiments described above are to be understood as illustrative and not restrictive in all aspects. In addition, the scope of the present invention is indicated by the following claims rather than the detailed description. Also, all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present invention.

1 is a schematic plan view of an organic light emitting display according to an embodiment of the present invention.

FIG. 2A is an exemplary cross-sectional view of the subpixel shown in FIG. 1; FIG.

FIG. 2B is another cross-sectional exemplary view of the subpixel shown in FIG. 1; FIG.

3A to 3B illustrate embodiments of implementing a color image in an organic light emitting display device according to an embodiment of the present invention.

4 is a hierarchical structure view of an organic light emitting diode according to an embodiment of the present invention.

5 is a circuit diagram of a subpixel according to a first embodiment of the present invention;

FIG. 6 is a driving waveform diagram schematically illustrating a method of driving the subpixel illustrated in FIG. 5.

7 is a circuit diagram of a subpixel according to a second embodiment of the present invention;

8 is a circuit diagram of a subpixel according to a third embodiment of the present invention;

9 is a circuit configuration diagram of a subpixel according to the fourth embodiment of the present invention.

10 is a circuit diagram of a subpixel according to a fifth embodiment of the present invention;

Fig. 11 is a circuit diagram of a subpixel according to the sixth embodiment of the present invention.

DESCRIPTION OF THE REFERENCE NUMERALS

110: substrate 120: display unit

130: sealing substrate 140: adhesive member

150: driver P: subpixel

Claims (10)

First, second and third switching transistors that are turned on in the same manner by the first scan signal supplied from the first scan wiring, fourth switching transistors turned on by the second scan signal supplied from the second scan wiring, First and second driving transistors in which threshold voltages are simultaneously programmed by the data signal when the first, second and third switching transistors are turned on and a data signal is supplied from a data line; A subpixel including a capacitor supplying the same data voltage to the organic light emitting diode and an organic light emitting diode emitting light when the first driving transistor is turned on and the fourth switching transistor is turned on; A scan driver configured to supply the first and second scan signals to the first and second scan wirings; And And a data driver for supplying the data signal to the data line. The method of claim 1, The first and second driving transistors, An organic light emitting display device which is a mirror transistor having the same size. The method of claim 1, The scan driver, The first scan signal is supplied to the first scan wiring so that the first and second driving transistors are simultaneously programmed, and the fourth switching transistor is turned on in a period where the first, second and third switching transistors are turned on. And an organic light emitting display for supplying the second scan signal to the second scan line so as to be turned off. The method of claim 1, The sub- The first switching transistor having one end connected to the data line and the gate connected to the first scan line, the second switching transistor having a gate connected to the first scan line and one end connected to the data line, A third switching transistor having a gate connected to one scan wiring and one end connected to the data wiring, a fourth switching transistor having a gate connected to the second scan wiring and one end connected to the other end of the third switching transistor; A gate connected to the other end of the first switching transistor, one end connected to the other end of the third switching transistor, and a gate connected to the other end of the first switching transistor; One end is connected to the other end of the second switching transistor and the other power line is connected to the first power line. The connected second driving transistor, a capacitor having one end connected to the first power line and the other end connected to the gate of the first and second driving transistors in common, and a first electrode connected to the other end of the fourth switching transistor. And the organic light emitting diode having a second electrode connected to a second power line. The method of claim 1, The sub- The first switching transistor having one end connected to the data line and the gate connected to the first scan line, the second switching transistor having a gate connected to the first scan line and one end connected to the data line, The third switching transistor having a gate connected to one scan line and having one end connected to the other end of the second switching transistor, and the fourth having a gate connected to the second scan wiring and one end connected to the other end of the third switching transistor A switching transistor, the first driving transistor having a gate connected to the other end of the first switching transistor, one end connected to the other end of the third switching transistor, and the other end connected to a first power line, and the other end of the first switching transistor The gate is connected to one end of the second switching transistor, A second driving transistor having the other end connected to the first power line, a capacitor having one end connected to the first power line and having the other end connected to the gate of the first and second driving transistors in common, and the other end of the fourth switching transistor. An organic light emitting display device comprising: the organic light emitting diode having a first electrode connected thereto and a second electrode connected to a second power line. The method of claim 1, The sub- The first switching transistor having one end connected to the data line and the gate connected to the first scan line, and the second switching transistor having a gate connected to the first scan line and one end connected to the other end of the first switching transistor. And a third switching transistor having a gate connected to the first scan wiring and having one end connected to the other end of the second switching transistor, and a gate connected to the second scan wiring and having one end connected to the other end of the third switching transistor. The fourth switching transistor connected to the second driving transistor, a gate connected to the other end of the second switching transistor, one end connected to the other end of the third switching transistor, and the other end connected to a first power line, and the second driving transistor; A gate is connected to the other end of the switching transistor and one end of the other end of the first switching transistor is connected. A second driving transistor connected to the first power line and having a second end connected to the first power line, a first end connected to the first power line, and a capacitor connected at the other end to a gate of the first and second driving transistors in common; And an organic light emitting diode having a first electrode connected to the other end of the transistor and a second electrode connected to the second power line. The method of claim 1, The sub- The first switching transistor having one end connected to the data line and the gate connected to the first scan line, and the second switching transistor having a gate connected to the first scan line and one end connected to the other end of the first switching transistor. And a third switching transistor having a gate connected to the first scan wiring and having one end connected to the other end of the second switching transistor, and a gate connected to the second scan wiring and having one end connected to the other end of the third switching transistor. The fourth switching transistor connected to the first driving transistor, a gate connected to the other end of the first switching transistor, one end connected to the other end of the third switching transistor, and the other end connected to a first power line, and the first driving transistor; A gate is connected to the other end of the switching transistor and once at the other end of the second switching transistor. A second driving transistor connected to the first power line and the other end connected to the first power line, a first end connected to the first power line, and a capacitor connected to the gate of the first and second driving transistors in common and the fourth switching circuit And an organic light emitting diode having a first electrode connected to the other end of the transistor and a second electrode connected to the second power line. The method of claim 1, The sub- The first switching transistor having one end connected to the data line and the gate connected to the first scan line, and the second switching transistor having a gate connected to the first scan line and one end connected to the other end of the first switching transistor. And a third switching transistor having a gate connected to the first scan line and having one end connected to the other end of the first switching transistor, and a gate connected to the second scan wiring and once at the other end of the third switching transistor. The fourth switching transistor connected to the first switching transistor, the first driving transistor having a gate connected to the other end of the first switching transistor, one end connected to the other end of the third switching transistor, and the other end connected to a first power supply wiring; A gate is connected to the other end of the first switching transistor and once at the other end of the second switching transistor. A second driving transistor connected to the first power line and having a second end connected to the first power line, a first end connected to the first power line, and a capacitor connected at the other end to a gate of the first and second driving transistors in common; And an organic light emitting diode having a first electrode connected to the other end of the transistor and a second electrode connected to the second power line. The method of claim 1, The sub- The first switching transistor having one end connected to the data line and the gate connected to the first scan line, the second switching transistor having a gate connected to the first scan line and one end connected to the data line, The third switching transistor having a gate connected to one scan line and having one end connected to the other end of the second switching transistor, and the fourth having a gate connected to the second scan wiring and one end connected to the other end of the third switching transistor A switching transistor, the first driving transistor having a gate connected to the other end of the first switching transistor, one end connected to the other end of the third switching transistor, and the other end connected to a first power line, and the other end of the first switching transistor The gate is connected to one end of the second switching transistor, A second driving transistor having the other end connected to the first power line, a capacitor having one end connected to the first power line and having the other end connected to the gate of the first and second driving transistors in common, and the other end of the fourth switching transistor. An organic light emitting display device comprising: the organic light emitting diode having a first electrode connected thereto and a second electrode connected to a second power line. 10. The method according to any one of claims 1 to 9, The transistors included in the sub- An organic light emitting display device which is a p-type transistor.

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