JP2006084819A - Organic el display apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To control color balance without using a plurality of power supplies in an organic EL display. <P>SOLUTION: A color organic EL display apparatus 1 comprises: a plurality of organic EL elements 10 arranged like a matrix correspondingly to a plurality of rows and a plurality of columns and including organic EL elements to be emitted by respectively different light emitting colors; a plurality of row wires 14 laid in each light emitting color to drive a plurality of organic EL elements; a selection means 18 for electrically connecting at least some of the row wires to an external power supply or a ground terminal for a prescribed period that a start time and end time are shifted in each row wire; and a plurality of column wires 12 allowing an electric current corresponding to display data to flow in order to drive the organic EL elements of the row electrically connected to the external power supply or the ground terminal: and can control the color balance of display by changing the prescribed period for electrically connecting the row wire to the external power supply or the ground terminal in each light emitting color. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a current-driven flat panel display (FPD) device, and more particularly, to a passive matrix driven color display organic electroluminescence (EL) display device.

  As a high-quality and thin self-luminous image display device, an organic EL display in which a large number of organic EL elements are arranged in a flat matrix is drawing attention. An organic EL element is a multilayer thin film device made of an organic material, and emits light according to an electric current. The organic EL element is also called an organic light emitting diode (organic LED) element because its voltage-current characteristics and light emitting mechanism are similar to those of the light emitting diode element.

  FIG. 7 shows the voltage-current characteristics of the organic EL element. In the figure, current characteristics with respect to a forward applied voltage through which current flows are schematically shown, and the current flows for a voltage equal to or higher than a certain threshold voltage (Vth). In this organic EL element, the light emission luminance increases almost in proportion to the current. In the case of reverse bias with the voltage direction reversed, almost no current flows.

  An organic EL display having the organic EL element as a display pixel is classified into an active matrix type and a passive matrix type depending on a driving method. In the active matrix type, each pixel (organic EL element) is driven by an active element such as a thin film transistor (TFT) element using polysilicon or amorphous silicon. In the passive matrix type, these active elements are used. Instead, each organic EL element is driven by a grid electrode wiring in which the column wiring and the row wiring are combined.

  FIG. 5 shows the basic configuration of a color organic EL display device 5 that performs passive matrix driving and its driving circuit. In this display device 5, the anode of each organic EL element is connected to the column wiring, the cathode is connected to the row wiring, the column wiring 52 and the row wiring 54 are wired in a grid pattern, and the column wiring and the row wiring are respectively connected. An organic EL element 50 is disposed at the intersection. The row wiring 54 is also called a scan line, and the column wiring is also called a data line. In the electric circuit in FIG. 5, the organic EL element 50 is indicated by a diode symbol 51. In this organic EL display device 5, red (R) organic EL elements 50 R, green (G) organic EL elements 50 G, and blue (B) organic EL elements 50 B are adjacent to each other in different colors in the same row. These are arranged so that the same emission color is adjacent to each other in the same column, and a color display is obtained by combining the organic EL elements 50 of the three primary emission colors of these lights. In order to obtain an image display by causing the organic EL display 5 to emit light according to desired display data, each column wiring is provided with a current source 56.

When an organic EL display is driven by a passive matrix method, an image is usually displayed by line sequential scanning. That is, in order to select only one selected row among the row wirings 54, for example, the scan driver IC or the like is provided with a selection means 58. The selection means 58 selects only one row wiring 54 at a time and connects it to an external ground terminal, and controls an output changeover switch 582 provided in accordance with the row wiring 54, for example, in a scan driver IC or the like. Since the row wirings sequentially selected by the selection means 58 are electrically connected to the ground for a predetermined period, during this period, each of the organic EL elements of each pixel for one row connected to this row Each element is caused to emit light at a target light emission luminance by passing a current according to image data using a current source 56 connected to the column wiring. At this time, the output changeover switch 582 of the row wiring of the other row not selected is connected to the positive power supply potential ( _Vcc ). As a result, a reverse bias voltage is applied to the organic EL elements in the unselected rows, so that no current flows through the organic EL elements 50. In line sequential scanning, the lines to be selected are sequentially switched to select all the lines on one screen, and an image on the entire screen is displayed. For example, in the case of displaying 8-bit gradation (256 gradations), the display data is given display data of 0 to 255, and the current source supplies a current having a current value corresponding to the display data for a predetermined period. Or outputs a current having a predetermined current value for a period corresponding to display data.
Patent Document 1 discloses a method for driving a passive matrix organic EL display.
Japanese Patent Laid-Open No. 11-143429

  In the organic EL element, the emission luminance per driving current (hereinafter referred to as “current efficiency”) differs for each emission color of R (red), G (green), and B (blue). For this reason, for example, in order to realize a good white display and obtain an appropriate color display, it is necessary to change the drive current value for each RGB as shown in FIG. 6, for example.

  However, when the drive current for each RGB is different, the current density of each of the RGB organic EL elements is different. Here, the current density is a drive current per area where the organic EL element is driven. In this case, as shown in FIG. 7, the forward voltage (EL voltage) of the organic EL element is increased according to the current density, so that current driving with a different voltage for each emission color must be performed. Here, as the power source supplied to the current source 56 of the driving device realized by an integrated circuit or the like, it is normal to use a common power source regardless of the light emission color, but a configuration in which the EL voltage is changed for each light emission color. Then, the utilization efficiency of the power source is deteriorated and the power consumption is increased.

  In order to prevent this problem, there is a method in which the area of the light emitting portion of the organic EL element is adjusted to the drive current ratio of each light emission color and the current density is made constant. However, in this case, it is necessary to produce a light-emitting organic EL element with good current efficiency, which makes it difficult to manufacture. In addition, the panel may appear colored instead of black when not lit. For example, when the area of the R light emitting portion is increased, the display device is colored red when not lit. This phenomenon is conspicuous when there is a color filter on the sub-pixel as in the white color filter method. Therefore, it is difficult to greatly change the area of the subpixel in accordance with the current efficiency of the emission color.

  An object of the present invention is to solve at least some of the above problems.

  In the present invention, in the color organic EL display device, the color balance is adjusted by making it possible to change the period during which the row wiring is electrically connected to the external power supply or the ground terminal. That is, in the present invention, a plurality of organic EL elements arranged in a matrix corresponding to a plurality of rows and a plurality of columns and having different emission colors are connected to organic EL elements of the same emission color in the same row. A plurality of row wirings and at least some of the plurality of row wirings are electrically connected to an external power source or a ground terminal for a predetermined period in which the start and end are shifted for each row wiring. And an organic EL element in the same column in accordance with display data so as to drive the organic EL element connected to the row wiring electrically connected to the external power source or the ground terminal. Provided is a color organic EL display device having a plurality of column wirings for flowing through the light source, wherein the predetermined period for electrically connecting the row wirings to an external power source or a ground terminal can be changed for each emission color The That. At this time, the emission colors may include red, green, and blue. When the first color, the second color, and the third color include red (R), green (G), and blue (B), color display is preferably realized using the three colors of red, green, and blue. . Note that the colors of red (R), green (G), and blue (B) in the present invention generally indicate emission colors that are recognized as perceptual colors. In the present invention, the reason why the emission color is different or the reason why the current efficiency is different for each emission color is not particularly limited, and the case where substantially different emission color and current efficiency are realized as a display device is widely targeted. That is, not only when the light emitting color and current efficiency differ because the materials constituting the organic EL element are different, but also, for example, the organic EL element that emits white light alone absorbs part of the wavelength of transmitted light, When different luminescent colors and different current efficiencies are realized by overlapping reflective color filters, or when the luminescent color is blue light with a short wavelength, green and red In this case, the present invention is also applicable to the case where different light emission colors and different current efficiencies are realized.

  In the present invention, at least an organic EL element that emits light in the first color and an organic EL element that emits light in the second color are arranged in a matrix corresponding to a plurality of rows and a plurality of columns. A plurality of organic EL elements in which organic EL elements having the same emission color are arranged adjacent to each other in each row, and organic EL elements having different emission colors are arranged adjacent to each other in the plurality of columns. An element, a plurality of row wirings provided corresponding to each row for driving the organic EL elements included in each of the plurality of rows, and an organic EL element included in each of the plurality of columns. In order to drive, a plurality of column wirings, each of which is provided corresponding to each column, for supplying a current corresponding to display data, and the plurality of row wirings are sequentially selected, and during a first predetermined period, The organic EL element of the first color The first row wiring to be moved is selected and electrically connected to an external power source or a ground terminal, and the second color organic EL element is driven during a second predetermined period following the first predetermined period. Selection means capable of selecting a second row wiring and electrically connecting it to an external power supply or a ground terminal so that the first predetermined period and the second predetermined period have different lengths. A color organic EL display device is provided.

  In the color organic EL display device, the plurality of organic EL elements further include an organic EL element that emits light of a third color, and the selection unit is configured to perform a third predetermined period following the second predetermined period. The third row wiring for driving the organic EL element of the third color is electrically connected to an external power source or a ground terminal, and the second predetermined period and the second predetermined period are both the second predetermined period. The period may be different from the predetermined period.

  Furthermore, the present invention includes at least an organic EL element that emits light in the first color and an organic EL element that emits light in the second color, and is arranged in a matrix corresponding to a plurality of rows and a plurality of columns. And each of the columns are arranged so that organic EL elements having different emission colors are adjacent to each other, and the first color included in a row of the plurality of rows. A row wiring group including a first row wiring for driving the organic EL element and a second row wiring for driving the organic EL element of the second color included in the row is associated with each row. In order to drive the plurality of row wiring groups provided and the organic EL elements included in each of the plurality of columns, a plurality of column wirings for supplying a current corresponding to display data are provided corresponding to each column. Column wiring and each of the plurality of row wiring groups Are sequentially selected so as to have overlapping group selection periods shifted from the start and end, and the first row wiring of the selected row wiring group is externally connected during the first predetermined period in the group selection period. Electrically connected to a power supply or ground terminal and electrically connected a second row wiring of the selected row wiring group to an external power supply or ground terminal for a second predetermined period during the group selection period. There is provided a color organic EL display device including selection means capable of setting the first predetermined period and the second predetermined period to periods having different lengths.

  In the color organic EL display device, the plurality of organic EL elements further include an organic EL element having a third emission color, and the row wiring group of the plurality of row wiring groups is included in the row. A third row wiring for driving the organic EL element of the color, and the column wiring of the plurality of column wirings also corresponds to display data in the organic EL element of the third color included in the column The selection means electrically connects the third row wiring of the selected row wiring group to an external power source or a ground terminal during a third predetermined period in the group selection period. And the selecting means can set the third predetermined period to a period having a different length from both the first predetermined period and the second predetermined period. The second color and the third color preferably include red, green, and blue.

  In the color organic EL display device, the selection unit overlaps each row wiring for driving at least some organic EL elements driven by each of at least one of the plurality of column wirings. More preferably, it is electrically connected to an external power source or a grounding terminal so that there is no period to do so.

  Furthermore, in the present invention, at least an organic EL element that emits light in the first color and an organic EL element that emits light in the second color are arranged in a matrix corresponding to a plurality of rows and a plurality of columns. In each and each column, organic EL elements having different emission colors are arranged adjacent to each other, and a plurality of organic EL elements and the first color organic included in a row of the plurality of rows A row wiring group including a first row wiring for driving the EL element and a second row wiring for driving the organic EL element of the second color included in the row is associated with each row. In order to drive the plurality of row wiring groups and the organic EL elements included in each of the plurality of columns, there are a plurality of column wirings corresponding to the respective columns. The column wiring and the plurality of row wiring groups differ at least. In the two row wiring groups, the row wirings included in each row wiring group that simultaneously drive the organic EL elements having the same light emission color are simultaneously selected and electrically connected to an external power supply or a ground terminal, and the light emission color organic EL elements are selected. Are simultaneously emitted in two row wirings, and a plurality of row wirings for driving other light emitting organic EL elements are not selected at the same time, and the other light emitting organic EL elements emit light by only one row wiring at the same time. And a color organic EL display device including a selection unit.

  In the color organic EL display device of the present invention, the color organic EL display device further includes a plurality of display current sources connected to each of the plurality of column wirings for flowing a current according to the display data, and each of the plurality of display current sources It is preferable that the current based on the same voltage source is applied to at least the display data that should emit light with respect to the organic EL elements having different emission colors.

  According to the color organic EL display device of the present invention, the luminance balance of R, G, and B of the organic EL element is adjusted by adjusting the period during which the driving current for driving the elements of each color is flowing. can do. Thereby, even when a single power supply is used without providing a power supply circuit for each emission color, adjusting the luminance of each emission color for the same luminance data to adjust the color balance and white balance, The use efficiency of the power source can be improved and power consumption can be reduced. Moreover, the above-mentioned period can be adjusted according to the light emission lifetime of the organic EL element of each light emission color instead of the point of color balance or white balance.

[Embodiment 1]
A first embodiment of the present invention is shown in FIGS.
FIG. 1 is a configuration diagram showing an electrical configuration of a part of a color organic EL display device 1 of the present embodiment. Compared with the color organic EL display device 5 shown in FIG. 5 as a conventional example, the arrangement of the R, G, and B organic EL elements 10 is changed. That is, among the plurality of rows, the same row of organic EL elements having the same emission color is arranged adjacent to each other, and among the plurality of columns, the same column is arranged so that organic EL elements of different emission colors are adjacent to each other. Is arranged. Although not shown, in the organic EL display device of the present embodiment, each organic EL element is fabricated so that the areas of the light emitting portions are equal regardless of the light emission color. In the present specification, numbers of row numbers and column numbers are appended as necessary to the reference numerals of the organic EL elements 10R, 10G, and 10B of the respective colors. In the present embodiment, R organic EL elements 10R ₁₁ and 10R ₁₂ , G organic EL elements 10G ₂₁ and 10G ₂₂ , and B organic elements in the first row, the second row, and the third row, respectively. The EL elements 10B ₃₁ and 10B ₃₂ are arranged adjacent to each other. In the first column and the second column, R, G, B organic EL elements 10R, 10G, 10B are organic EL elements 10R ₁₁ , 10G ₂₁ , 10B ₃₁ , 10R ₄₁ , 10G ₅₁ , 10B in this order. ₆₁ ... are arranged repeatedly so that the different emission colors are adjacent to each other. Each organic EL element 10 is indicated by a diode symbol 11 in the electric circuit.

The organic EL elements 10 included in each of the plurality of rows are driven by row wirings 13, 14, 15 provided corresponding to each row. In addition, the organic EL elements 10 included in each of the plurality of columns are driven by column wirings 12 that are provided corresponding to the respective columns that pass a current corresponding to display data.
A display current source 16 for flowing a current corresponding to display data is connected to each column wiring 12.

As for the row wiring 13, 14 and 15, for example, the first row of the row wiring 13 of SCAN1 drives the organic EL element 10R _11, 10R ₁₂ of R, the row wiring 14 of the second row of SCAN2, G The organic EL elements 10G ₂₁ , 10G ₂₂ ... Are driven, and the row wiring 15 in the third row of the SCAN 3 drives the B organic EL elements 10B ₃₁ , 10B ₃₂ .

Each of the row wirings 13, 14, 15 is connected to the selection means 18. The selection unit 18 has a control unit (not shown) for controlling the switch 182 provided therein so as to sequentially select the plurality of row wirings. Accordingly, the selection unit 18 selects the row wiring 13 of SCAN1, which is a row wiring for driving the R organic EL elements 10R ₁₁ , 10R ₁₂ ... For a predetermined period for driving the R organic EL element 10R. Then, after the predetermined period has elapsed, the G organic EL elements 10G ₂₁ , 10G ₂₂ ... Are driven for a predetermined period for driving the G organic EL elements 10G. The row wiring 14 of SCAN2, which is the wiring, is selected and electrically connected to the ground terminal, and after the predetermined period, the B organic EL element is driven for a predetermined period for driving the B organic EL element 10B. select row wirings 15 of the element 10B _31, 10B ₃₂ ... is a row wiring driving the SCAN3 electrically connected to the ground terminal. Thereafter, the column wirings 13, 14, and 15 of SCAN4, SCAN5, and SCAN6 are sequentially selected, and when all the row wirings are selected, they are sequentially selected again from the row wiring 13 of SCAN1. The unselected row wiring is connected to the positive power supply potential (V _cc ), and light emission in that row is suppressed.

  The predetermined period during which each row is selected by the selection means 18 can be changed by the emission color. That is, a predetermined period for driving the R organic EL element 10R, a predetermined period for driving the G organic EL element 10G, and a predetermined period for driving the B organic EL element 10B Any period, any two periods, or all periods may be different, or all may be the same. Thereby, the color balance can be adjusted.

  FIG. 2 is a timing chart of signals given to the respective wirings when the R, G, and B organic EL elements have different current efficiencies. Each row wiring is selected when the logical value is LOW, and the drive current from the column wiring flows through the row wiring. Scanning by selecting the row wiring proceeds in the order of SCAN1, SCAN2, SCAN3, SCAN4,. Each column is sequentially selected by this selection, and the organic EL elements 10R, 10G, and 10B are sequentially electrically connected to the ground terminal. In accordance with this timing, the current source 16 connected to the column wiring passes a drive current. The predetermined period for the row wirings 13, 14, and 15 of SCAN1, SCAN2, and SCAN3 is set so as to obtain a good color balance according to the current efficiency. The drive current signals 22R, 22G, and 22G corresponding to the display data of the uppermost current source 16 in FIG. 2 correspond to current values generated from the same voltage source. In the figure, a data signal corresponding to display data to be set to 100% luminance is described. Although not shown, for display data whose luminance should be lower, the current source 16 can flow a smaller current value or a current for a shorter period.

  Although not shown, the selection means 18 can be provided with an appropriate register for adjusting the timing, or although not shown, the selection means 18 is controlled from a control circuit that controls the operation of the selection means 18. It can be controlled by adjusting the clock to do. In the organic EL display device according to the present embodiment, it is possible to adjust a predetermined period for each of the R, G, and B jobs and adjust the luminance balance of each color.

[Embodiment 2]
A first embodiment of the present invention is shown in FIGS.
FIG. 3 is a configuration diagram showing an electrical configuration of a part of the color organic EL display device 3 of the present embodiment. Compared with the color organic EL display device 1 of the first embodiment shown in FIG. 1, the arrangement of the R, G, and B organic EL elements 30 is changed. That is, organic EL elements having different emission colors are arranged adjacent to each other in a plurality of rows and columns. For example, in the first column, the organic EL elements 30 are disposed in the organic EL elements 30R ₁₁ and 30G _12. , 30B ₁₃ , 30R ₁₄ , 30G ₁₅ , 30B ₁₆ ..., And in the first row, the organic EL elements 30 are arranged with the organic EL elements 30R ₁₁ , 30B ₂₁ , 30G ₃₁ .

The row wirings 33, 34, and 35 are made into a row wiring group corresponding to each one row, and in order to drive the R organic EL elements 30R ₁₁ , 30R ₁₄ ... Row wiring 33 (SCAN1), row wiring 34 (SCAN2) for driving the G organic EL elements 30G ₁₂ , 30G ₁₅ ..., And row for driving the B organic EL elements 30B ₁₃ , 30B ₁₆ . Wiring 35 (SCAN3) is included. Further, in each of the columns, a column wiring 32 for supplying a current corresponding to display data is provided corresponding to each column. Each organic EL element 30 is indicated by a diode symbol 31 in the electric circuit. The organic EL elements 30 included in each of the plurality of columns are driven by column wirings 32 that correspond to the respective columns and pass a current corresponding to display data. A display current source 36 for flowing a current corresponding to display data is connected to each column wiring 32.

  The row wirings 33, 34, and 35 are divided into groups of three row wirings corresponding to the three colors. The row wiring groups are configured so that the row wirings are grouped into three consecutive lines, SCAN1 to SCAN3, SCAN4 to 6 in order, so that each row wiring group corresponds to each row of organic EL elements arranged in a matrix. Has been. Each of the row wirings 33, 34, and 35 is connected to the selection unit 38. The selection unit 38 controls a switch 382 provided therein so as to select the plurality of row wirings at a predetermined timing.

  The predetermined period in which the current flows, selected by the selection means 38, differs for each emission color. That is, a predetermined period for driving the R organic EL element 10R, a predetermined period for driving the G organic EL element 10G, and a predetermined period for driving the B organic EL element 10B Any period, any two periods, or all periods may be different, or all periods may be the same. Thereby, the color balance can be adjusted.

FIG. 4 is a timing chart of signals given to the respective wirings when the organic EL elements of R, G, and B colors have different current efficiencies. The row wiring is selected when the logical value is LOW, and the driving current flows through the row wiring as in the first embodiment. In scanning by sequentially selecting the row wirings 33, 34, and 35, a row wiring group composed of SCAN1, SCAN2, and SCAN3 (hereinafter referred to as “first row wiring group”) is selected during the period 42, and the selection is performed. Is not completed, a row wiring group consisting of SCAN4, SCAN5, and SCAN6 (hereinafter referred to as a “second row wiring group”) is selected during a period 44, and so on. The drive currents are made to flow in such a manner that they are sequentially selected so as to have overlapping periods. The period during which each row wiring is electrically connected to the external power supply or the ground terminal is determined according to the period during which the organic EL element 30 driven by the row wiring emits light. For example, the row wiring 33 of SCAN1 is electrically connected to the ground terminal for a long period to drive the R organic EL elements 30R ₁₁ , 30R ₁₄ ..., And the row wiring 34 of SCAN2 is connected to the G organic EL element. 30G ₁₂ , 30G ₁₅ ... Are electrically connected to the ground terminal for a short period of time, and the row wiring 35 of the SCAN 3 is used to drive the B organic EL elements 30B ₁₃ , 30B ₁₆ . Are electrically connected to the ground terminal for the length of time schematically shown in FIG. Although the period for selecting the row wiring group (group selection period) may be overlapped as periods 44, 46, and 48, the selection means 38 simultaneously applies to a plurality of organic EL elements driven by a certain column wiring. The switch 382 is controlled so as not to be driven by the row wiring. For example, paying attention to the column wiring 32 of DATA2, as shown in FIG. 3, this column wiring 32 drives the organic EL elements 30G ₁₂ , 30R ₂₂ , and 30B _32, and drives these organic EL elements. The row wirings 33, 34, and 35 are SCAN2, SCAN4, and SCAN9 in this order, and the period in which these row wirings are stranded and electrically connected to the ground terminal does not overlap.

As an example, the operation in the period from the start to the end of the period 44 of the second row wiring group will be described including the operation in other row wiring groups when the display data is 100% light emission luminance data. . The description is made only for the range of the column wirings 32 of DATA1 to 3, but the same applies to the other columns. In the first row wiring group, until the end of the period 42, it stops the driving current signal 42G by column wiring 32 of the DATA2, the selection of the organic EL element 30G ₁₂ by the row wiring 34 SCAN2 is completed. Then, the period 44 starts. In period 44, the row wiring 33 of SCAN4 included in the second row line group is selected, the drive current signals 44R by column wiring 32 of DATA2 flows to the organic EL element 30R ₂₂ in the second row. Thereby, the organic EL element 30R ₂₂ starts lighting. At this time, since the state of the period 42 of the first row wiring group is continued, the column wirings 32 of DATA1 and DATA3 output the driving current signal 42R and the driving current signal 44B, respectively, and the row of SCAN1 The wiring 33 and the row wiring 35 of SCAN3 are selected. Accordingly, during this period, the pixels of the organic EL elements 30R ₁₁ , 30B ₂₃ , and 30R ₂₂ are lit, and at the same time, the R organic EL elements 30 are lit in two rows.

Then, the column wirings 32 of DATA1 and 3 stop the drive current signals 42R and 42B, and the selection of SCAN1 and SCAN3 is also completed. Thereby, the period 44 ends. Thereafter, the row wirings 34 and 35 of SCAN5 and 6 included in the second row wiring group are selected, and the drive current signals 44G and 44B are output from the column wirings 32 of DATA3 and 1, respectively. The organic EL elements 30G ₂₃ and 30B ₂₁ in the second row are turned on by the drive current signals 44G and 44B.

Further, when the time elapses and immediately before the period 46 starts, before the period 44 ends, the drive current signal 44G by the column wiring 32 of the DATA3 is stopped, the selection by the row wiring 34 of the SCAN5 is completed, and the organic EL element 30G ₂₃ is turned off. Then, the row wiring 33 of SCAN7 included in the row wiring group consisting of the row wirings 33, 34, and 35 of SCAN7 to 9 (hereinafter referred to as “third row wiring group”) is selected, and the column wiring 32 of DATA3 is used. The output of the drive current signal 46R is started, and the organic EL element 30R ₃₃ in the third row starts lighting. The column wiring 32 of DATA1 and DATA2 continuously outputs the drive current signals 44B and 44R, and the row wiring 33 of SCAN4 and the row wiring 35 of SCAN6 included in the second row wiring group select the selection of the second row. This continues until period 44 ends. Accordingly, the organic EL elements 30B ₂₁ and 30R _{22 in} the second row are turned on until the period 44 of the second row wiring group starts.

  The period during which each row wiring 33, 34, 35 is selected is set so as to obtain a good color balance according to the current efficiency of the organic EL element of each color. Each drive current signal in FIG. 4 is a current signal of the same voltage source for R, G, and B. Although not shown, the current source 36 can pass a smaller current value for display data whose luminance should be lower, or the current source 36 can pass a current for a shorter period of time. This is the same as the first embodiment.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications, changes and combinations can be made based on the technical idea of the present invention. is there.

1 is a configuration diagram illustrating an electrical configuration of an organic EL display device according to an embodiment of the present invention. It is a timing chart which shows operation | movement of the organic electroluminescence display in the embodiment of this invention. 1 is a configuration diagram illustrating an electrical configuration of an organic EL display device according to an embodiment of the present invention. It is a timing chart which shows operation | movement of the organic electroluminescence display in the embodiment of this invention. It is a block diagram which shows the electrical structure of the conventional organic EL display apparatus. It is a timing chart which shows operation | movement of the organic electroluminescence display in the embodiment of this invention. It is a characteristic view which shows the voltage-current characteristic of an organic EL element.

Explanation of symbols

1, 3 Organic EL display device 11, 31 Diode 10, 30 Organic EL element 12, 32 Column wiring 13, 14, 15, 33, 34, 35 Row wiring 18, 38 Selection means 5 Conventional organic EL display device 51 Diode 50 Organic EL element 52 Column wiring 54 Row wiring 58 Selection means

Claims (10)

A plurality of organic EL elements arranged in a matrix corresponding to a plurality of rows and a plurality of columns and having different emission colors;
A plurality of row wirings connected to organic EL elements of the same emission color in the same row,
Selecting means for electrically connecting at least some of the plurality of row wirings to an external power source or a ground terminal during a predetermined period in which the start and end of each row wiring are shifted;
A plurality of columns for flowing a current corresponding to display data to the organic EL elements in the same column so as to drive the organic EL elements connected to the row wiring electrically connected to the external power supply or the ground terminal With wiring and
A color organic EL display device in which the predetermined period for electrically connecting the row wiring to an external power source or a ground terminal can be changed for each emission color.   The color organic EL display device according to claim 1, wherein the emission colors include red, green, and blue. It includes at least an organic EL element that emits light in the first color and an organic EL element that emits light in the second color, and is arranged in a matrix corresponding to a plurality of rows and a plurality of columns, and each of the plurality of rows emits light. A plurality of organic EL elements arranged so that organic EL elements having the same color are adjacent to each other, and organic EL elements having different emission colors are adjacent to each other in the plurality of columns;
A plurality of row wirings each provided with a row wiring for driving the organic EL elements included in each of the plurality of rows corresponding to each row;
In order to drive the organic EL elements included in each of the plurality of columns, a plurality of column wirings provided corresponding to each column, and a column wiring for passing a current corresponding to display data;
The plurality of row wirings are sequentially selected, and a first row wiring for driving the organic EL element of the first color is selected and electrically connected to an external power source or a ground terminal during a first predetermined period. Selecting a second row wiring for driving the organic EL element of the second color and electrically connecting it to an external power source or a ground terminal during a second predetermined period following the first predetermined period; A color organic EL display device comprising: selection means capable of setting the first predetermined period and the second predetermined period to periods having different lengths. The plurality of organic EL elements further includes an organic EL element that emits light in a third color,
The selecting means electrically connects a third row wiring for driving the organic EL element of the third color to an external power source or a ground terminal during a third predetermined period following the second predetermined period. , The third predetermined period can be a period having a different length from the first predetermined period and the second predetermined period,
The color organic EL display device according to claim 3, wherein the first color, the second color, and the third color include red, green, and blue. It includes at least an organic EL element that emits light in the first color and an organic EL element that emits light in the second color, and is arranged in a matrix corresponding to a plurality of rows and a plurality of columns, and each of the rows and each of the columns And a plurality of organic EL elements arranged so that organic EL elements having different emission colors are adjacent to each other;
A first row wiring for driving the first color organic EL elements included in the row of the plurality of rows, and a second for driving the second color organic EL elements included in the row. A plurality of row wiring groups each including a row wiring group including a plurality of row wirings,
In order to drive the organic EL elements included in each of the plurality of columns, a plurality of column wirings provided corresponding to each column, and a column wiring for passing a current corresponding to display data;
Each group of the plurality of row wiring groups is sequentially selected so as to have overlapping group selection periods shifted from the start and end, and the selected row is selected during a first predetermined period in the group selection period. The first row wiring of the wiring group is electrically connected to an external power source or a ground terminal, and the second row wiring of the selected row wiring group is externally connected during the second predetermined period in the group selection period. A color organic EL display device comprising: selection means that is electrically connected to a power source or a ground terminal, and is capable of making the first predetermined period and the second predetermined period have different lengths. The plurality of organic EL elements further include an organic EL element having a third emission color,
The row wiring group of the plurality of row wiring groups further includes a third row wiring for driving the organic EL element of the third color included in the row,
The column wiring of the plurality of column wirings is configured to pass a current corresponding to display data also to the third color organic EL elements included in the column,
The selecting means electrically connects the third row wiring of the selected row wiring group to an external power supply or a ground terminal during a third predetermined period in the group selection period.
The selection unit may set the third predetermined period to a period having a length different from that of the first predetermined period and the second predetermined period.
The color organic EL display device according to claim 5, wherein the first color, the second color, and the third color include red, green, and blue.   The selecting means includes an external power supply or a plurality of row wirings for driving at least some organic EL elements driven by each of at least any one of the plurality of column wirings so that there is no overlapping period. The color organic EL display device according to claim 5 or 6, which is electrically connected to a ground terminal.   The color organic EL display device according to claim 3, wherein either or both of the first predetermined period and the second predetermined period are different.   The period of any one of the first predetermined period, the second predetermined period, and the third predetermined period, any two periods, or all the periods are different. The color organic EL display device according to any one of the above. A plurality of display current sources connected to each of the plurality of column wirings for flowing a current according to the display data;
Each of the plurality of display current sources supplies current based on the same voltage source to display data that should emit light at least brightly with respect to organic EL elements having different emission colors. The color organic EL display device according to any one of 9.

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