JP2010122461A - Organic electroluminescence display device - Google Patents

Abstract

An organic light emitting display device capable of reducing the number of wirings and reducing the circuit area without losing the function as a pixel circuit including a compensation circuit.
A pixel circuit includes a scanning circuit, a common circuit that captures video data based on scanning pulses and outputs a current corresponding to the video data, and a current corresponding to the video data in the horizontal direction. In order to distribute each of the RGB organic EL elements to each other, a selection circuit 12A that selectively drives the RGB organic EL elements adjacent in the horizontal direction in accordance with a drive signal sent through the drive line is arranged and scanned. A common circuit 11A is disposed between the line 31 and the selection circuit 12A. The selection circuit 12A includes a plurality of drive TFTs that selectively drive the RGB organic EL elements adjacent in the horizontal direction, and a plurality of drive TFT regions. It is composed of a plurality of potential control TFTs that are separately arranged and set potentials after compensating for variations in TFT characteristics.
[Selection] Figure 5

Description

  The present invention relates to an active matrix organic light emitting diode (AM-OLED), and more particularly to a small, high definition organic electroluminescent display device having a small layout area.

  The pixel circuit for AM-OLED has a larger number of elements and wiring than a liquid crystal display (LCD), which is disadvantageous for high definition. In particular, when the pixel circuit includes a compensation circuit that compensates for variations in TFT characteristics such as TFT (Thin-Film Transistor) threshold, which has many elements and wiring, the problem is to reduce the pixel area. .

  A conventional active matrix organic light emitting display device will be described with reference to FIGS. 12 and 13 (see, for example, Patent Document 1). FIG. 12 is a diagram illustrating a configuration of a conventional active matrix organic light emitting display device. FIG. 13 is a circuit diagram showing a configuration of a pixel circuit of a conventional active matrix organic light emitting display device.

  In FIG. 12, a plurality of pixel circuits 10, a plurality of organic EL elements 21A and 21B, a plurality of selection switches 6A and 6B, a scanning line drive circuit 30, a plurality of scanning lines 31 (1 to n), and data A line driving circuit 40, a plurality of data lines 41 (1 to m), a selection line driving circuit 60, and a plurality of selection lines 61A and 61B are drawn.

  In FIG. 13, an N-channel TFT 1, a capacitor 2, a P-channel TFT 3, an N-channel TFT 4, a capacitor 5, a P-channel TFT 6A, a P-channel TFT 6B, an organic EL element 21A, an organic EL The element 21B, the scanning line 31, the data line 41, the selection line 61A, the selection line 61B, and the reset line 71 are drawn.

  FIG. 13 proposes a pixel circuit of an organic light emitting display device including a TFT and a common capacitor and a TFT for selecting an organic EL element of the pixel. In this method, a common element and a selection element are provided between pixels adjacent in the vertical (row) direction. In FIG. 13, TFT 1 to capacitor 5 are common elements, and TFTs 6A and 6B are selection elements (selection switches). This is a typical example in the case where a compensation circuit including the TFT 4 and the capacitor 5 is shared. As a driving method, a time division method is adopted, and one vertical period is driven in two.

  Another conventional active matrix organic light emitting display device will be described with reference to FIG. 14 (see, for example, Patent Document 2). FIG. 14 is a circuit diagram showing a configuration of a pixel circuit of another conventional active matrix organic electroluminescence display device.

  In FIG. 14, a P-channel TFT 1, a capacitor 2, a P-channel TFT 3, a P-channel TFT 7R, a P-channel TFT 7G, a P-channel TFT 7B, a scanning line 31, a data line 41, and light emission control. A line 62R, a light emission control line 62G, a light emission control line 62B, an organic EL element 22R that emits red light, an organic EL element 22G that emits green light, and an organic EL element 22B that emits blue light are depicted. .

  FIG. 14 shows a method in which a common element and a selection element are provided between pixels adjacent in the horizontal (column) direction. The organic EL elements 22R, 22G, and 22B are selected by the light emission control signals EC_R, G, and B. As a driving method, a time division method is adopted, and one vertical period is driven in three divisions.

  Another conventional active matrix organic light emitting display device will be described with reference to FIG. 15 (see, for example, Patent Document 3). FIG. 15 is a circuit diagram showing a configuration of a pixel circuit of another conventional active matrix organic light emitting display device.

  In FIG. 15, a P-channel TFT 1, a capacitor 2, a P-channel TFT 3, a P-channel TFT 4, an N-channel TFT 6, an N-channel TFT 8 having a drain applied with a compensation voltage Vsus, and a scanning line 31, the data line 41, and the organic EL element 21 are drawn.

  This is a circuit configuration in which a TFT 8 for supplying a constant potential compensation voltage Vsus is added to the pixel circuit including the compensation circuit shown in FIG. Depending on the manufacturer, the compensation voltage Vsus changes to VDD or Vref. The TFT 8 plays a role of fixing one side of the capacitor 2 to the compensation voltage Vsus having a constant potential when the organic EL element 21 emits light in order to compensate for variations in TFT characteristics such as a threshold value, thereby reducing the pixel circuit area. Therefore, in the case of commonality, it is considered that the TFT should be standardized. In FIG. 15, the TFT that becomes the selection element in the case of sharing is the TFT 6. The layout method is not disclosed.

JP 2003-122306 A (FIGS. 1 and 5) Japanese Patent Laying-Open No. 2005-148749 (FIG. 10) Japanese Patent Laying-Open No. 2005-157308 (FIG. 10)

  The problems of the other conventional active matrix organic light emitting display shown in FIG. 15 will be described with reference to FIG. FIG. 16 is a diagram showing a pixel circuit and operation waveforms in which elements of another conventional active matrix organic light emitting display device are shared.

  When the elements of the pixel circuit including the compensation circuit shown in FIG. 15 are shared, the circuit configuration shown in FIG. This is a case where all the transistors are constituted by P-channel TFTs.

  As shown in FIG. 16A, the pixel circuit 10 includes a common circuit 11, a selection circuit 12, and organic EL elements 22R, 22G, and 22B. The common circuit 11 includes a P-channel TFT 1, a capacitor 2, a P-channel TFT 3, a P-channel TFT 4, and a P-channel TFT 8. The selection circuit 12 includes a P-channel TFT 7R, a P-channel TFT 7G, and a P-channel TFT 7B.

  The video data is captured by the common circuit 11, and the current corresponding to the video data is distributed to the organic EL element 22R, the organic EL element 22G, and the organic EL element 22B by the TFT 7R, TFT 7G, and TFT 7B of the selection circuit 12.

  An example of the operation waveform is shown in FIG. Video data writing (Write) and light emission (Emission) are driven in the order of red (R) → green (G) → blue (B) by dividing one vertical period into three.

  The problem of the conventional pixel circuit occurs when the circuit shown in FIG. In other words, since the number of wirings of the compensation voltage line Vsus, the scanning lines SW1n and SW2n, and the driving lines SW3Rn, SW3Gn, and SW3Bn is large, the circuit area is increased. As a result, there is a problem that high resolution cannot be realized. In order to avoid complications, the signal names and signal line names may be the same.

  Further, the increase in the number of circuits that drive these increased drive lines SW3Rn, SW3Gn, and SW3Bn causes a problem in that the yield decreases and the cost increases. The cause of this problem is that the number of selected elements increases and the number of signal lines for driving them increases as the number of elements is reduced by sharing.

  The present invention has been made in order to solve the above-described problems. The object of the present invention is to reduce the number of wirings and reduce the circuit area without losing the function as a pixel circuit including a compensation circuit. An organic electroluminescent display device that can be obtained is obtained.

  The organic light emitting display device according to the present invention is an active matrix organic light emitting display device including a plurality of pixel circuits, wherein the pixel circuit includes a scanning line connected to a scanning line driving circuit, and the scanning line. Based on the scan pulse sent from the drive circuit through the scan line, the video data sent from the data line drive circuit through the data line is fetched and a current corresponding to the video data is output, and the common circuit In order to distribute the current corresponding to the output video data to each of the plurality of organic EL elements adjacent in the horizontal direction, a plurality of adjacent pixels in the horizontal direction are driven by a drive signal sent from the scanning line drive circuit through the drive line. And a selection circuit that selectively drives the organic EL element, and the common circuit is disposed between the scanning line and the selection circuit. The selection circuit is disposed separately from a plurality of drive transistors for selectively driving a plurality of organic EL elements adjacent in the horizontal direction and a region of the plurality of drive transistors, and the characteristic variation of the transistors is reduced. It is composed of a plurality of potential control transistors that perform potential setting after compensation.

  The organic light emitting display according to the present invention has an effect that the number of wirings can be reduced and the circuit area can be reduced without losing the function as a pixel circuit including a compensation circuit.

Embodiment 1 FIG.
An active matrix organic light emitting display according to Embodiment 1 of the present invention will be described with reference to FIGS. FIG. 1 is a diagram showing a configuration of an active matrix organic light emitting display device according to Embodiment 1 of the present invention. In addition, in each figure, the same code | symbol shows the same or equivalent part.

  1, an active matrix organic light emitting display (display panel) according to Embodiment 1 of the present invention includes a plurality of pixel circuits 10A (P11 to Pnm), a scanning line driving circuit 30, and a plurality of scans ( Gate: Gate) line 31 (1-n), drive lines EM-R, EM-G, EM-B, data line drive circuit 40, a plurality of data lines 41 (1-m), and a power supply line A PVDD, a reference potential supply line Vref, and a connection portion 50 to an external drive IC are provided.

  As will be described later, the pixel circuit 10A includes a common circuit 11A, a selection circuit 12A, and organic EL elements 22R, 22G, and 22B. The pixel circuit 10A includes a compensation circuit for suppressing luminance variation due to a difference in capability of the driving TFT. The common circuit 11A basically includes one selection TFT, a capacitor for storing video (video) data, and one drive TFT. Furthermore, a TFT constituting a part of the compensation circuit is included. Note that the compensation circuit is a shared type of a circuit called a threshold (Vt) compensation circuit, and the driving method is the same as the conventional driving method described above.

  The scanning line driving circuit 30 drives the gate of the selection TFT of the common circuit 11A constituting the pixel circuit 10A, and serves to transfer predetermined video data to the capacitor. Since it is driven in the horizontal direction, it is also called a horizontal driving circuit, and is composed of a shift register and a driving TFT.

  The data line driving circuit 40 has a role of driving a video data signal corresponding to the pixel address. In order to drive data in the vertical direction, it is also called a vertical drive circuit, and is composed of a shift register and a switch circuit.

  The connection unit 50 transmits signals necessary for driving the display panel, a power supply, a video data signal, and the like to the panel unit. Usually, it is prepared on the assumption that a connector such as an FPC is soldered. Recently, the size has been further reduced, and the number of video data signal driving ICs formed on glass has increased.

  The first embodiment is different from the second and third embodiments described later in the number of drive signals (EM-R, G, B, W), the number of data lines in one pixel, and the number of power supply lines. However, the basic operation is the same.

  FIG. 2 is a diagram showing a pixel circuit and operation waveforms in which elements of the active matrix organic light emitting display device according to the first embodiment of the present invention are shared.

  A problem with the conventional pixel circuit is that the number of drive lines for drive signals is increased by sharing the elements. Therefore, in order to reduce the number of wirings, the function of the signal line SW1n shown in FIG. 16A is shifted to the drive line SW3n, and the TFT 8 that fixes one side of the capacitor 2 to the compensation voltage Vsus at a constant potential when the organic EL element emits light. This function ensures the normal operation by increasing the number of TFTs. In order to avoid complications, the signal names and signal line names may be the same.

  In FIG. 2A, the pixel circuit 10A includes a common circuit 11A, a selection circuit 12A, and organic EL elements 22R, 22G, and 22B. The common circuit 11A is provided with a P-channel selection TFT 1, a capacitor 2, a P-channel driving TFT 3, and a P-channel TFT 4 constituting a part of the compensation circuit. The selection circuit 12A includes a P-channel TFT 7R that drives the red organic EL element 22R, a P-channel TFT 7G that drives the green organic EL element 22G, and a P-channel TFT 7B that drives the blue organic EL element 22B. A P-channel TFT 8R, a P-channel TFT 8G, and a P-channel TFT 8B.

  In FIG. 2B, the drive signals SW3Rn, SW3Gn, and SW3Bn are used to write video data (Write) and light emission (Emission) one by one in the order of red (R) → green (G) → blue (B). It is driven by dividing the period into three.

  As can be seen by comparing FIG. 16 and FIG. 2, the signal line SW1n can be reduced. At first glance, the circuit area is likely to increase. However, since the TFTs 7R, 7G, 7B, TFTs 8R, 8G, and 8B can be laid out under or between the wirings of the drive lines SW3Rn, SW3Gn, and SW3Bn, the circuit area is reduced and the aperture ratio is improves.

  FIG. 3 is a diagram showing a simplified layout of the pixel circuit of the active matrix organic light emitting display device according to Embodiment 1 of the present invention.

  In FIG. 3, (a) shows a bottom emission type (Bottom Emission Type), and (b) shows a top emission type. A common circuit 11A, a selection circuit 12A, and organic EL elements 22R, G, and B are laid out. In the case of the top emission type, the organic EL elements 22R, G, and B are laid out under the common circuit 11A and the selection circuit 12A.

  The compensation circuit is susceptible to parasitic capacitance, drive noise, and instability of the power supply value. In order to prevent this, the area of the common circuit 11A and the area of the selection circuit 12A are separated and laid out. The common circuit 11A region is laid out so as to exist between the scanning line 31 and the selection circuit 12A region.

  FIG. 4 is a circuit diagram showing the configuration of the pixel circuit of the active matrix organic light emitting display device according to Embodiment 1 of the present invention.

  The circuit diagram of FIG. 4 shows an arrangement image close to the actual pixel circuit of the organic light emitting display device. In FIG. 4, a pixel circuit 10A includes a common circuit 11A, a selection circuit 12A, an organic EL element 22R that emits red (R), an organic EL element 22G that emits green (G), and a blue (B). It comprises an organic EL element 22B that emits light.

  The common circuit 11A takes in (accumulates) video data sent from the data line driving circuit 40 through the data line 41 based on the scanning pulse sent from the scanning line driving circuit 30 through the scanning line 31, and stores the video data in this video data. For outputting a corresponding current to the selection circuit 12A, a P-channel selection TFT 1, a capacitor 2, a P-channel driving TFT 3, and a P-channel TFT 4 constituting a part of the compensation circuit are provided. Yes.

  The selection circuit 12A is driven from the scanning line driving circuit 30 in order to distribute the current corresponding to the video data output from the common circuit 11A to the organic EL elements 22R, 22G, and 22B adjacent in the horizontal (column) direction. This is for selectively driving the organic EL elements 22R, 22G, and 22B adjacent in the horizontal (column) direction by drive signals sent through the lines EM-R, EM-G, and EM-B. P-channel driving TFT (driving transistor) for driving the organic EL element 22R-MDR (corresponding to the TFT 7R in FIG. 2A) and P-channel driving TFT (driving transistor) for driving the green organic EL element 22G- MDG (corresponding to TFT 7G in FIG. 2A) and P-channel driving TFT (driving transistor) for driving blue organic EL element 22B- DB (corresponding to TFT7B in FIG. 2 (a)) is provided.

  Further, the selection circuit 12A includes a P-channel potential control TFT (potential control transistor) -MCR (a TFT 8R in FIG. 2A) that fixes one side of the capacitor 2 to a constant potential reference potential Vref when the organic EL element 22R emits light. Equivalent), and a P-channel potential control TFT (potential control transistor) -MCG (corresponding to the TFT 8G in FIG. 2A) that fixes one side of the capacitor 2 to a constant potential reference potential Vref when the organic EL element 22G emits light. A P-channel potential control TFT (potential control transistor) -MCB (corresponding to TFT 8B in FIG. 2A) is provided to fix one side of the capacitor 2 to a constant reference potential Vref when the organic EL element 22B emits light. ing.

  FIG. 5 is a diagram showing a layout of the pixel circuit of the active matrix organic light emitting display device according to Embodiment 1 of the present invention. In the second and third embodiments described later, the layout of the pixel circuit is the same as that shown in FIG.

Conditions (1) to (6) for reducing the occupied area will be described below.
(1) A selection circuit that is connected to a compensation voltage supply line Vsus, such as the TFT 8 in FIG. 16A, that should be used in common, as shown in FIG. 4, is connected to a reference potential supply line Vref. It is diverted to 12A potential control TFT-MCR, TFT-MCG, TFT-MCB.

  (2) As shown in FIG. 5, the region of the common circuit 11A is arranged between the scanning line 31 and the region of the selection circuit 12A.

  (3) Accordingly, in the case of the bottom emission type shown in FIG. 3A, as shown in FIG. 5, the scanning line 31, the common circuit 11A, the selection circuit 12A, and the organic EL elements 22R, 22G, They are arranged in the order of B (light emitting area).

  (4) As shown in FIG. 5, in the selection circuit 12A, the driving TFT-MDR, MDG, and MDB for driving the organic EL elements 22R, G, and B, and the potential setting after compensating the transistor characteristic variation are performed. In other words, potential control TFTs MCR, MCG, and MCB that fix the storage element (capacitor 2) to a constant reference potential Vref are arranged separately.

  (5) As shown in FIG. 4, the selection circuit 12A is laid out under the drive lines EM-R and EM-G and between the drive lines EM-G and EM-B. That is, the drive TFTs-MDR, MDG and the potential control TFTs-MCR, MCG on the side close to the area of the common circuit 11A drive the drive lines EM-R, EM- that supply drive signals for causing the organic EL elements 22R, 22G to emit light. Place under the G wiring. Further, the drive TFT-MDB and the potential control TFT-MCB on the side close to the organic EL elements 22R, G, B (light emitting region) cause the drive line EM-G and the organic EL element 22B adjacent thereto to emit light. It arrange | positions between the drive lines EM-B which supply a drive signal.

  The driving TFT-MDR, MDG on the side close to the area of the common circuit 11A and the channel of the potential control TFT-MCR, MCG are perpendicular to the driving lines EM-R, EM-G, and the driving TFT-MDB on the side close to the light emitting area. The channel of the potential control TFT-MCB is laid out in parallel with the drive line EM-B. The reason why the TFT channel on the side close to the area of the common circuit 11A is perpendicular to the drive line is that there is already an S (source) / D (drain) contact of the TFT of the selection circuit 12A on the common circuit 11A side. The reason why the TFT channel close to the light emitting region is laid out in parallel with the drive line is that a new TFT S / D contact is not made on the light emitting region side.

  (6) In order to make the parasitic capacitances of the drive lines uniform between the drive lines as much as possible, the number of wires traversed is made as much as possible.

  As shown in FIG. 5, the common circuit 11A and the selection circuit 12A are separated and laid out. The common circuit 11A is laid out so as to exist between the scanning line 31 and the selection circuit 12A. In the selection circuit 12A, the driving TFT-MDR, MDG, and MDB and the potential control TFT-MCR, MCG, and MCB are separated and laid out. As a result, the number of wirings can be reduced and the circuit area can be reduced without losing the function as the pixel circuit 10A including the compensation circuit.

Embodiment 2. FIG.
An active matrix organic light emitting display according to Embodiment 2 of the present invention will be described with reference to FIGS. FIG. 6 is a diagram showing a configuration of an active matrix organic light emitting display device according to Embodiment 2 of the present invention.

  6, an active matrix organic light emitting display (display panel) according to Embodiment 2 of the present invention includes a plurality of pixel circuits 10B (P11 to Pnm), a scanning line driving circuit 30, and a plurality of scanning ( Gate: Gate) line 31 (1-n), drive lines EM-R, EM-G, EM-B, EM-W, data line drive circuit 40, and a plurality of data lines 41 (1-m) In addition, a power supply line PVDD, a reference potential supply line Vref, and a connection portion 50 to an external drive IC are provided.

  The circuit area is larger than that of the RGB configuration of the first embodiment described above in the case of the RGBW four sub-pixels of the second embodiment. Therefore, a technique capable of reducing the circuit area is more important in a pixel having an RGBW configuration.

  FIG. 7 is a circuit diagram showing a configuration of a pixel circuit of an active matrix organic light emitting display device according to Embodiment 2 of the present invention. FIG. 8 is a diagram showing operation waveforms of the pixel circuit of the active matrix organic electroluminescence display device according to the second embodiment of the present invention.

  The circuit diagram of FIG. 7 shows an arrangement image close to the actual pixel circuit of the organic light emitting display device. In FIG. 7, a pixel circuit 10B includes a common circuit 11B, a selection circuit 12B, an organic EL element 22R that emits red (R), an organic EL element 22G that emits green (G), and a blue (B). An organic EL element 22B that emits light and an organic EL element 22W that emits white (W) light are included.

  The common circuit 11B captures (accumulates) video data sent from the data line driving circuit 40 through the data line 41 based on the scanning pulse sent from the scanning line driving circuit 30 through the scanning line 31, and stores the video data in this video data. For outputting a corresponding current to the selection circuit 12B, a P-channel selection TFT 1, a capacitor 2, a P-channel driving TFT 3, and a P-channel TFT 4 constituting a part of the compensation circuit are provided. Yes.

  In addition, the selection circuit 12B distributes the current corresponding to the video data output from the common circuit 11B to the organic EL elements 22R, 22G, 22B, and 22W adjacent in the horizontal (column) direction. The organic EL elements 22R, 22G, 22B, and 22W that are adjacent to each other in the horizontal (column) direction are selectively driven by drive signals sent from the drive lines EM-R, EM-G, EM-B, and EM-W. A P-channel driving TFT (driving transistor) -MDR for driving the red organic EL element 22R, a P-channel driving TFT (driving transistor) -MDG for driving the green organic EL element 22G, A P-channel driving TFT (driving transistor) -MDB for driving the blue organic EL element 22B, and a white (W) organic EL element 22 A driving TFT (driving transistor) -MDW the P-channel driving is provided a.

  Further, the selection circuit 12B includes a P-channel potential control TFT (potential control transistor) -MCR that fixes one side of the capacitor 2 to a constant potential reference potential Vref when the organic EL element 22R emits light, and the organic EL element 22G emits light. A P-channel potential control TFT (potential control transistor) -MCG that fixes one side of the capacitor 2 to a constant reference potential Vref, and one side of the capacitor 2 is fixed to a constant reference potential Vref when the organic EL element 22B emits light. P-channel potential control TFT (potential control transistor) -MCB, and P-channel potential control TFT (potential control transistor) -MCW that fixes one side of the capacitor 2 to a constant reference potential Vref when the organic EL element 22W emits light. Is provided.

  FIG. 7 shows a case where RGBW is adopted, and one common circuit 11B is composed of four drive transistors MDR, MDG, MDB, MDW and four potential control transistors MCR, MCG, MCB, MCW. The selection circuit 12B is arranged.

  In FIG. 8, drive signals EM-R, EM-G, EM-B, and EM-W are written in video data in the order of red (R) => green (G) => blue (B) => white (W). The light emission is driven by dividing one vertical period into four.

Conditions (1) to (5) for reducing the occupied area will be described below.
(1) A selection circuit that is connected to a compensation voltage supply line Vsus, such as the TFT 8 in FIG. 16A, that should be used in common, as shown in FIG. 7, is connected to a reference potential supply line Vref. This is diverted to 12B potential control TFT-MCR, TFT-MCG, TFT-MCB, and TFT-MCW.

  (2) As shown in FIG. 5, the area of the common circuit 11B is arranged between the scanning line 31 and the area of the selection circuit 12B.

  (3) Therefore, in the case of the bottom emission type shown in FIG. 3A, as shown in FIG. 5, the scanning line 31, the common circuit 11B, the selection circuit 12B, and the organic EL elements 22R, G, They are arranged in the order of B and W (light emitting area).

  (4) As shown in FIG. 5, in the selection circuit 12B, after driving TFT-MDR, MDG, MDB, and MDW for driving each organic EL element 22R, G, B, and W and the variation in transistor characteristics are compensated Potential setting is performed, that is, potential control TFTs MCR, MCG, MCB, and MCW that fix the storage element (capacitor 2) to a constant reference potential Vref are arranged separately.

  (5) As shown in FIG. 7, the selection circuit 12B is laid out under the drive lines EM-R, EM-G, and EM-B and laid out between the drive lines EM-B and EM-W. That is, the drive TFT-MDR, MDG, MDB and the potential control TFT-MCR, MCG, MCB on the side close to the area of the common circuit 11B supply a drive line for supplying a drive signal for causing the organic EL elements 22R, 22G, 22B to emit light. It arrange | positions under the wiring of EM-R, EM-G, and EM-B. Further, the drive TFT-MDW and the potential control TFT-MCW on the side close to the organic EL elements 22R, G, B, and W (light emitting region) are connected to the drive line EM-B and the organic EL element 22W adjacent thereto. It arrange | positions between the drive lines EM-W which supply the drive signal made to light-emit.

  The driving TFT-MDR, MDG, MDB on the side close to the area of the common circuit 11B and the channels of the potential control TFT-MCR, MCG, MCB are perpendicular to the driving lines EM-R, EM-G, EM-B, and the light emitting area. The channels of the driving TFT-MDW and the potential control TFT-MCW on the near side are laid out in parallel with the driving line EM-W. The reason why the channel of the TFT close to the region of the common circuit 11B is perpendicular to the drive line is that the S (source) / D (drain) contact of the TFT of the selection circuit 12B is already on the common circuit 11B side. The reason why the TFT channel close to the light emitting region is laid out in parallel with the drive line is that a new TFT S / D contact is not made on the light emitting region side.

Embodiment 3 FIG.
An active matrix organic light emitting display according to Embodiment 3 of the present invention will be described with reference to FIGS. FIG. 9 is a diagram showing a configuration of an active matrix organic light emitting display device according to Embodiment 3 of the present invention.

  9, the active matrix organic light emitting display (display panel) according to Embodiment 3 of the present invention includes a plurality of pixel circuits 10C (P11 to Pnm), a scanning line driving circuit 30, and a plurality of scans ( Gate: Gate) lines 31 (1 to n), drive lines EM-RG and EM-BW, a data line drive circuit 40, a plurality of data lines 41 (1 to m), a power supply line PVDD, and a reference A potential supply line Vref and a connection part 50 to an external drive IC are provided.

  FIG. 10 is a circuit diagram showing a configuration of a pixel circuit of an active matrix organic light emitting display device according to Embodiment 3 of the present invention. FIG. 11 is a diagram showing operation waveforms of the pixel circuit of the active matrix organic electroluminescence display device according to the third embodiment of the present invention.

  In the case of the RGBW configuration, it is preferable to share every two pixels, and the combination of colors is preferably dependent on the light emission time and the light emission efficiency. That is, it is preferable that colors having similar light emission times and light emission efficiencies are simultaneously emitted. In the case of the RGBW configuration, the third embodiment can ensure a large aperture ratio.

  The circuit diagram of FIG. 10 shows an arrangement image close to the actual pixel circuit of the organic light emitting display device. In FIG. 10, a pixel circuit 10C includes a common circuit 11C, a selection circuit 12C, an organic EL element 22R that emits red (R), an organic EL element 22G that emits green (G), and a blue (B). An organic EL element 22B that emits light and an organic EL element 22W that emits white (W) light are included.

  The common circuit 11C takes in (accumulates) video data sent from the data line driving circuit 40 through the data line 41 based on the scanning pulse sent from the scanning line driving circuit 30 through the scanning line 31, and stores the video data in this video data. This is for outputting a corresponding current to the selection circuit 12C, and each includes two P-channel selection TFTs 1, a capacitor 2, a P-channel driving TFT 3, and two P-channel TFTs 4 constituting a part of the compensation circuit. It is provided one by one.

  The selection circuit 12C also distributes the current corresponding to the video data output from the common circuit 11C to the organic EL elements 22R, 22G, 22B, and 22W adjacent in the horizontal (column) direction, respectively. For selectively driving the organic EL elements 22R and 22B and the organic EL elements 22G and 22W adjacent in the horizontal (column) direction by a drive signal sent from the drive lines EM-RB and EM-GW Thus, a P-channel driving TFT (driving transistor) -MDR for driving the red organic EL element 22R, a P-channel driving TFT (driving transistor) -MDG for driving the green organic EL element 22G, and a blue organic EL P-channel driving TFT (driving transistor) -MDB for driving the element 22B and white (W) organic EL element 22W Driving TFT of a P-channel driving a (driving transistor) -MDW is provided.

  Further, the selection circuit 12C includes a P-channel potential control TFT (potential control transistor) -MCRB1 that fixes one side of the capacitor 2 to a constant reference potential Vref when the organic EL element 22R emits light, and the organic EL element 22G emits light. A P-channel potential control TFT (potential control transistor) -MCGW1 that fixes one side of the capacitor 2 to a constant reference potential Vref and one side of the capacitor 2 to a constant potential reference potential Vref when the organic EL element 22B emits light. P-channel potential control TFT (potential control transistor) -MCRB2, and P-channel potential control TFT (potential control transistor) -MCGW2 for fixing one side of the capacitor 2 to a constant reference potential Vref when the organic EL element 22W emits light Is provided.

  FIG. 10 shows a case where RGBW is adopted, and two driving TFTs-MDR and MDG, two potential control TFTs-MCRB1 and MCGW1, and two drivings, for one common circuit 11C of two sets of TFT1 to TFT4. A selection circuit 12C composed of TFT-MDB, MDW, two potential control TFT-MCRB2, MCGW2 is arranged.

  FIG. 11A shows a case where one vertical period is divided into two and the ratio of the R / B emission period to the G / W emission period is 1: 1. Compared to the four divisions shown in FIG. 8 of the second embodiment, there are twice the light emission period, and a current density of ½ and a life of twice can be expected. The combination of colors that emit light at the same time is not limited to the combination of R · B and G · W, but is preferably combined in the order of emission time and emission efficiency. The combination of R · G and B · W or R · W and G -W may be combined, and the light emission time can be easily adjusted.

  FIG. 11B shows a case where one vertical period is divided into two and the ratio of the R / B emission period to the G / W emission period is 2: 1. This ratio is not limited to 2: 1, such as 1: 1, 1.5: 1, 3: 1, etc. The R / B emission period is the same as or longer than the G / W emission period. It only has to be long. By setting the period of the light emitting element made of a material having a small light emission time and light emission efficiency longer, the lifetime can be extended. Since the light emission time can be adjusted, the white balance can be adjusted more finely.

Conditions (1) to (5) for reducing the occupied area will be described below.
(1) A selection circuit that is connected to a compensation voltage supply line Vsus, such as the TFT 8 in FIG. 16A, that should be used in common, as shown in FIG. 10, is connected to a reference potential supply line Vref. It is diverted to 12C potential control TFT-MCRB1, MCGW1, MCRB2, and MCGW2.

  (2) As shown in FIG. 5, the area of the common circuit 11C is arranged between the scanning line 31 and the area of the selection circuit 12C.

  (3) Therefore, in the case of the bottom emission type shown in FIG. 3A, as shown in FIG. 5, the scanning line 31, the common circuit 11C, the selection circuit 12C, and the organic EL elements 22R, G, They are arranged in the order of B and W (light emitting area).

  (4) In the selection circuit 12B, the driving TFT-MDR and MDG for driving the organic EL elements 22R and G, and the potential setting after compensating for the characteristic variation of the transistor, that is, the storage element (capacitor 2) is determined. The potential control TFT-MCRB1 and MCGW1 fixed to the reference potential Vref are arranged separately. Further, the driving TFT-MDB, MDW for driving each organic EL element 22B, W and the potential setting after compensating for the characteristic variation of the transistor are performed, that is, the storage element (capacitor 2) is set to the reference potential Vref having a constant potential. The potential control TFT-MCRB2 and MCGW2 to be fixed are arranged separately. In the entire selection circuit 12B, the driving TFT is disposed in the central portion, and the potential control TFT is disposed separately on both sides of the central driving TFT.

  (5) As shown in FIG. 10, the selection circuit 12C is laid out under the drive line EM-RB and between the drive lines EM-RB and EM-GW. That is, the driving TFT-MDR and MDB on the side closer to the area of the common circuit 11C and the potential control TFT-MCRB1 and MCRB2 simultaneously convert the red organic EL element 22R and the blue organic EL element 22B that are close in light emission time and light emission efficiency. It is arranged under the wiring of the drive line EM-RB that supplies a drive signal to emit light. Further, the drive TFT-MDG, MDW and the potential control TFT-MCGW1, MCGW2 on the side close to the organic EL elements 22R, G, B, W (light emission region) are adjacent to the drive line EM-RB and the light emission. It arrange | positions between drive line EM-GW which supplies the drive signal which light-emits green organic EL element 22G and white organic EL element 22W with near time and luminous efficiency simultaneously.

  The driving TFT-MDR, MDB on the side close to the area of the common circuit 11C, and the channels of the potential control TFT-MCRB1, MCRB2 are perpendicular to the driving line EM-RB, and on the side close to the light emitting area, the driving TFT-MDG, MDW, The channels of the potential control TFT-MCGW1 and MCGW2 are laid out in parallel with the drive line EM-GW. The reason why the channel of the TFT near the area of the common circuit 11C is perpendicular to the drive line is that there is already an S (source) / D (drain) contact of the TFT of the selection circuit 12C on the common circuit 11C side. The reason why the TFT channel close to the light emitting region is laid out in parallel with the drive line is that a new TFT S / D contact is not made on the light emitting region side.

  In the pixel circuit including the compensation circuit of the active matrix organic light emitting display device according to each embodiment of the present invention, the circuit area can be made smaller than before, and a high-resolution OLED panel can be realized.

1. From the condition (1) for reducing the occupied area of each embodiment, there is an effect that the number of wirings can be reduced.
2. From the conditions (2), (3), and (4) for reducing the occupied area of each embodiment, there is an effect that the layout can be efficiently performed while satisfying the characteristics required for the circuit.
3. From the condition (5) for reducing the occupation area of each embodiment, there is an effect that the contact area can be eliminated and the layout area can be reduced.
4). In the case of RGBW, it is particularly effective to reduce the occupied area by making it common for every two sub-pixels (sub-pixels).
5. In the case of RGBW that is shared by two sub-pixels (sub-pixels), it is more effective to control the life and white balance of the OLED light-emitting material by emitting R and B and G and W simultaneously.

It is a figure which shows the structure of the active matrix type organic electroluminescent display apparatus which concerns on Embodiment 1 of this invention. It is a figure which shows the pixel circuit and operation waveform which shared the element of the active matrix type organic electroluminescent display apparatus which concerns on Embodiment 1 of this invention. It is a figure which shows the simplified layout of the pixel circuit of the active matrix type organic electroluminescent display apparatus which concerns on Embodiment 1 of this invention. It is a circuit diagram which shows the structure of the pixel circuit of the active matrix type organic electroluminescent display apparatus which concerns on Embodiment 1 of this invention. It is a figure which shows the layout of the pixel circuit of the active matrix type organic electroluminescent display apparatus which concerns on Embodiment 1 of this invention. It is a figure which shows the structure of the active matrix type organic electroluminescent display apparatus which concerns on Embodiment 2 of this invention. It is a circuit diagram which shows the structure of the pixel circuit of the active matrix type organic electroluminescent display apparatus which concerns on Embodiment 2 of this invention. It is a figure which shows the operation | movement waveform of the pixel circuit of the active matrix type organic electroluminescent display apparatus which concerns on Embodiment 2 of this invention. It is a figure which shows the structure of the active matrix type organic electroluminescent display apparatus which concerns on Embodiment 3 of this invention. It is a circuit diagram which shows the structure of the pixel circuit of the active matrix type organic electroluminescent display apparatus which concerns on Embodiment 3 of this invention. It is a figure which shows the operation | movement waveform of the pixel circuit of the active matrix type organic electroluminescent display apparatus which concerns on Embodiment 3 of this invention. It is a figure which shows the structure of the conventional active matrix type organic electroluminescent display apparatus. It is a circuit diagram which shows the structure of the pixel circuit of the conventional active matrix type organic electroluminescent display apparatus. It is a circuit diagram which shows the structure of the pixel circuit of another conventional active matrix type organic electroluminescent display apparatus. It is a circuit diagram which shows the structure of the pixel circuit of the other conventional active matrix type organic electroluminescent display apparatus. It is a figure which shows the pixel circuit which shared the element of the other conventional active matrix type organic electroluminescent display apparatus, and an operation waveform.

Explanation of symbols

  1 selection TFT, 2 capacitor, 3 drive TFT, 10A pixel circuit, 10B pixel circuit, 10C pixel circuit, 11A common circuit, 11B common circuit, 11C common circuit, 12A selection circuit, 12B selection circuit, 12C selection circuit, 22R red Organic EL element, 22G green organic EL element, 22B blue organic EL element, 22W white organic EL element, 30 scanning line driving circuit, 31 scanning line, 40 data line driving circuit, 41 data line, 50 connection part.

Claims (9)

An active matrix organic light emitting display device comprising a plurality of pixel circuits,
The pixel circuit includes:
A scanning line connected to the scanning line driving circuit;
A common circuit that takes in video data sent from the data line driving circuit through the data line based on a scanning pulse sent from the scanning line driving circuit through the scanning line, and outputs a current corresponding to the video data;
In order to distribute the current corresponding to the video data output from the common circuit to a plurality of organic EL elements adjacent in the horizontal direction, the drive signal sent from the scanning line drive circuit through the drive line in the horizontal direction And a selection circuit that selectively drives a plurality of adjacent organic EL elements,
The common circuit is disposed between the scanning line and the selection circuit;
The selection circuit includes:
A plurality of drive transistors for selectively driving a plurality of organic EL elements adjacent in the horizontal direction;
An organic light emitting display device comprising: a plurality of potential control transistors arranged separately from the plurality of drive transistor regions and configured to set potentials after compensating for variations in transistor characteristics. The organic light emitting display device according to claim 1, wherein the selection circuit is disposed below the drive lines and between the drive lines. The channel of the transistor of the selection circuit on the side close to the common circuit is arranged perpendicular to the drive line,
3. The organic light emitting display device according to claim 1, wherein the channel of the transistor of the selection circuit on the side close to the opposite side of the common circuit is arranged in parallel with the drive line. The plurality of organic EL elements are a red organic EL element, a green organic EL element, and a blue organic EL element,
A red driving transistor for driving the red organic EL element and a red potential control transistor corresponding to the red organic EL element are disposed under a red driving line for supplying a driving signal for causing the red organic EL element to emit light. And
A green driving transistor for driving the green organic EL element and a green potential control transistor corresponding to the green organic EL element are disposed under a green driving line for supplying a driving signal for causing the green organic EL element to emit light. And
A blue driving transistor for driving the blue organic EL element and a blue potential control transistor corresponding to the blue organic EL element supply a driving signal for causing the green driving line and the blue organic EL element to emit light. The organic light emitting display device according to claim 2, wherein the organic light emitting display device is disposed between the lines. The plurality of organic EL elements are a red organic EL element, a green organic EL element, a blue organic EL element, and a white organic EL element,
A red driving transistor for driving the red organic EL element and a red potential control transistor corresponding to the red organic EL element are disposed under a red driving line for supplying a driving signal for causing the red organic EL element to emit light. And
A green driving transistor for driving the green organic EL element and a green potential control transistor corresponding to the green organic EL element are disposed under a green driving line for supplying a driving signal for causing the green organic EL element to emit light. And
A blue driving transistor for driving the blue organic EL element and a blue potential control transistor corresponding to the blue organic EL element are disposed under a blue driving line for supplying a driving signal for causing the blue organic EL element to emit light. And
A white driving transistor that drives the white organic EL element and a white potential control transistor that corresponds to the white organic EL element supply a driving signal that causes the blue driving line and the white organic EL element to emit light. The organic light emitting display device according to claim 2, wherein the organic light emitting display device is disposed between the lines. The plurality of organic EL elements are organic EL elements of a first color, a second color, a third color, and a fourth color,
A first color driving transistor for driving the first color organic EL element; a third color driving transistor for driving the third color organic EL element; and a first color corresponding to the first color organic EL element. The potential control transistor and the third color potential control transistor corresponding to the organic EL element of the third color simultaneously emit light of the first color organic EL element and the third color organic EL element having a light emission time or light emission efficiency close to each other. Disposed under a first drive line for supplying a first drive signal;
A second color driving transistor for driving the second color organic EL element; a fourth color driving transistor for driving the fourth color organic EL element; and a second color corresponding to the second color organic EL element. The fourth color potential control transistor corresponding to the potential control transistor and the fourth color organic EL element includes the second color organic EL element and the fourth color that have a light emission time or light emission efficiency close to the first drive line. The organic electroluminescence display device according to claim 2, wherein the organic EL display device is disposed between second drive lines that supply a second drive signal for causing the organic EL elements to emit light simultaneously. The organic electroluminescence display according to claim 6, wherein the organic EL elements of the first color, the second color, the third color, and the fourth color are organic EL elements of red, green, blue, and white, respectively. apparatus. The organic light emitting display according to claim 6, wherein a ratio of a light emission period of the first drive signal and a light emission period of the second drive signal is 1: 1 in one vertical period. The light emission period of the first drive signal is the same as the light emission period of the second drive signal in one vertical period, or is longer than the light emission period of the second drive signal in one vertical period. The organic electroluminescent display device according to claim 7.

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