JP2010021063A - Organic electroluminescent display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laminated organic EL display device having little change in color hue. <P>SOLUTION: The organic EL display device has at least one or more pixels, the pixel is composed of two sub-pixels, the sub-pixel is formed by laminating two layers of a light-emitting element obtained by holding an organic light-emitting layer containing at least a luminescent layer by electrodes, and each luminescent layer is made to emit light by applying a voltage between the electrodes of the light-emitting element. In this display device, one layer of the organic light-emitting layers is formed commonly over all pixels, and one of the light-emitting elements of each sub-pixel containing the common organic light-emitting layer is controlled so as not to emit light. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a multi-layer organic EL display device in which an organic layer including a light emitting layer is sandwiched between a pair of electrodes and the light emitting layer emits light by applying a voltage between both electrodes.

  In order to extend the lifetime of an element in an organic EL display device, a structure in which organic EL elements are stacked has been proposed. In Patent Document 1, one pixel is composed of two subpixels, and two EL layers exhibiting different emission colors are stacked on one subpixel with electrodes interposed therebetween. The organic EL display device has complicated process steps because all the light emitting layers are individually formed on the upper and lower sides.

In order to reduce the number of steps, it can be considered that an EL layer including a light emitting layer of the same color is formed in common for two subpixels. For example, in the first subpixel, a first EL layer showing a first emission color and a third EL layer showing a third emission color are stacked with an electrode interposed therebetween. In the second subpixel, a second EL layer that exhibits the second emission color and a third EL layer that exhibits the third emission color are stacked with an electrode interposed therebetween. The first EL layer and the second EL layer are juxtaposed, and the third EL layer is formed in common for both the first and second subpixels. If the EL layer is formed as described above, the process becomes simple. However, it has been found that the following problem occurs when the light emitting layer of the same color is formed in common to the two subpixels.
Japanese Patent Laid-Open No. 2005-174639

  Since the organic EL element has a size equivalent to the wavelength, it strongly receives the light interference effect. Therefore, in order to obtain desired light emission efficiency and chromaticity, it is necessary to satisfy an appropriate optical interference condition. Since the first EL layer and the second EL layer juxtaposed between the two subpixels have different emission colors, the film thicknesses of the organic layers for optimizing the interference effect are also different. As a result, the third EL layer formed simultaneously over the two sub-pixels has different interference effects at a position where it is stacked on the first EL layer and a position where it is stacked on the second EL layer. For this reason, it was found that when the third EL layer is caused to emit light, different colors are produced in the portion laminated on the first EL layer and the portion laminated on the second EL layer, which adversely affects the image quality.

  An object of the present invention is to provide an organic EL display device with reduced adverse effects on image quality.

  The organic EL display device of the present invention has at least one pixel, the pixel is composed of two subpixels, and the subpixel includes an organic light emitting layer including at least a light emitting layer sandwiched between electrodes. An organic EL display device configured by laminating two layers of light emitting elements and emitting light from each of the light emitting layers by applying a voltage between the electrodes of the light emitting elements, wherein one layer of the organic light emitting layer extends over all pixels. It is formed in common, and one of the light emitting elements of each subpixel including the common organic light emitting layer is controlled to emit no light.

  In the present invention, since one of the light emitting elements of each sub-pixel including the organic light emitting layer formed in common over all pixels is controlled to emit no light, it is possible to make the light emitting element whose optical interference distance is not optimal emit no light. And high-quality display without color misregistration is possible.

  Further, by switching the non-emission level according to the integrated luminance value of the display screen or the luminance value of one pixel, it is possible to simultaneously improve the life of the organic light emitting layer and improve the image quality.

  Hereinafter, the organic EL display device of the present invention and the manufacturing method thereof will be described. In addition, the well-known or well-known technique of the said technical field is applied regarding the part which is not illustrated or described in particular in this specification. The embodiment described below is one embodiment of the present invention and is not limited thereto.

  Hereinafter, embodiments of the present invention will be described.

(Embodiment 1)
FIG. 4 is a diagram showing a pixel arrangement of the active matrix organic EL display device according to the first embodiment, and a layout of scanning lines and data lines.

  The pixels P are arranged in a matrix shape of n rows and m columns in the row direction and the column direction, and scanning lines R1, R2,... ), And data lines D1, D2,..., Dm (all m lines, hereinafter referred to as D as a representative) for connecting pixels in the column direction. A selection signal is sequentially applied to the scanning lines R to select pixels in units of rows. A display signal that varies with time is applied to the data line D in the column direction, and the display signal at that time is supplied to the pixel P in the selected row.

  A pixel circuit corresponding to each pixel P is provided at an intersection of the scanning line and the data line. This pixel circuit has known configurations such as a current programming method and a voltage programming method. Here, the programming means that a selection signal is sequentially applied to the scanning line R, a video signal is supplied from the data line D to each pixel P in the selected row, and a video is generated by a capacitor such as a capacitor provided in the pixel. This is an operation for holding a signal. A period during which the selection signal is applied to the scanning line R of each row is a programming period. This period is shifted in time by one programming period for each row.

  Each row moves to the light emission period when the programming period ends. A current corresponding to the video signal held in the holding capacitor of each pixel circuit is generated and supplied to the light emitting element. The light emitting element emits light with a luminance corresponding to the current.

  The organic EL display device of the present invention is configured so that each pixel emits a plurality of different colors in time order. One frame period is divided into one programming period and a plurality of light emission periods. During one programming period, all the video signals of different colors are programmed in the pixel circuit of the selected row, and then a plurality of light emission periods. Each color is emitted. Light emission with luminance corresponding to the video signal is performed in each light emission period, and a temporally synthesized color image is obtained.

  Each pixel circuit is provided with a switching TFT and a current control TFT in addition to the above-mentioned storage capacitor. In addition, a plurality of data lines for each column for supplying a video signal to the pixel circuit are provided for each color as shown in the following example. As another method, color-specific signals may be supplied in a time division manner using a single data line.

  Next, the configuration of one pixel in the organic EL display device of the present invention will be described with reference to FIG.

In FIG. 6, one pixel is composed of two subpixels P1 and P2. Further, both P1 and P2 have a structure in which two layers of light emitting elements each having an organic light emitting layer sandwiched between a pair of electrodes are stacked. In this embodiment, P1 is a stack of R light emitting elements and B (B ₁ ) light emitting elements, and P2 is a stack of two layers of G light emitting elements and B (B ₂ ) light emitting elements.

11 is a glass substrate, 12 is a planarization layer, 13 is a reflective first anode electrode (for R light emitting element) as a lower electrode, and 14 is a reflective first anode electrode (for G light emitting element) as a lower electrode. , 15 is a red (R) organic light emitting layer, 16 is a green (G) organic light emitting layer, 17 is a cathode layer, 18 is a blue (B) organic light emitting layer, and 19 is a second anode electrode (B ₁ light emitting element). use), 20 denotes a second anode electrode 2 (for _{B 2} light-emitting element). Each organic light emitting layer is composed of a plurality of organic layers including a light emitting layer, and in this embodiment, description will be made using a four-layer structure of a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer.

  Although not described in detail because it is not the essence of the present invention, a TFT (thin film transistor) constituting a pixel circuit is formed on the glass substrate 11, and an insulating layer is formed to protect the TFT (thin film transistor). Subsequently, an organic planarization layer 12 is formed to planarize the irregularities generated by the TFT formation.

  Further, after forming a contact hole in the organic planarization layer 12 for making electrical contact with each drain terminal of the previous TFT, the anode electrodes 13 and 14 are fabricated. In addition, although either a wet process or a dry process may be used for manufacturing these pixel electrodes, the anode electrodes 13 and 14 are preferably formed separately.

  After UV / ozone cleaning as pretreatment, vacuum baking is performed to deposit an organic EL layer on the substrate.

  A hole transport layer is formed on each of the anode electrodes 13, 14, an R (red) light emitting layer is formed in a region corresponding to the anode electrode 13, and a G (green) is formed in a region corresponding to the anode electrode 14. ) Is formed with a desired film thickness.

  Subsequently, after forming an electron transport layer and an electron injection layer, an electrode made of a transparent conductive material such as ITO or IZO or a semi-transparent electrode made of Ag, Al or the like is formed as the cathode electrode 17.

  Here, an explanation regarding the film thickness values of the R organic light emitting layer and the G organic light emitting layer is shown with reference to FIG. FIG. 7 is a schematic view showing an optical distance between the anode electrode 13 and the anode electrode 14 which are reflection electrodes from the light emitting region of each organic light emitting layer in the first embodiment.

When light emission occurs in each organic light emitting layer, the light is repeatedly extracted, reflected, refracted, transmitted, absorbed, and the like due to the difference in the refractive index and absorption coefficient of each constituent layer. The amount of light extracted increases as the light passing through various paths interfere with each other and strengthen each other. When the influence of interference is considered, the interference effect between the light directly traveling in the light extraction direction from the light emitting position and the light reflected on the reflection surface of the reflective electrode and traveling in the extraction direction is maximized. At this time, by satisfying the following relational expression (1), an improvement in extraction efficiency due to interference is expected.
2L / λ + δ / 2π = m (1)
(In the formula, L is an optical distance between the light emitting region of the organic light emitting layer and the reflective surface of the reflective electrode, δ is a phase shift amount δ in the reflective electrode, and m is a natural number.)
The formula (1) is described in the document Deppe J. Modern. In Optics Vol 41, No. 2, p325 (1994), it is derived from the interference enhancement condition of the EL emission spectrum in the resonance structure.

  Table 1 shows the optimum optical path lengths for the light emission of the G organic light emitting layer 16 and the R organic light emitting layer 15 in the case of m = 2 in accordance with the above interference conditional expression.

  λ1 is a wavelength to be enhanced with respect to light emission from the G organic light emitting layer 16, and L1 is an optical distance between the light emitting region in the G organic light emitting layer 16 and the reflecting surface of the first anode electrode. λ2 is a wavelength to be strengthened with respect to light emission from the R organic light emitting layer 15, and L2 is an optical distance between the light emitting region in the R organic light emitting layer 15 and the reflecting surface of the first anode electrode 13.

  Since the phase shift in the reflective metal film is approximately π, δ is calculated as π. λ1 set the interference peak wavelength of the G organic light emitting layer 16 to 530 nm, and λ2 set the interference peak wavelength of the R organic light emitting layer 15 to 620 nm. As can be seen from Table 1, the appropriate optical path length varies depending on the emission wavelength to be enhanced.

  That is, since each R organic light emitting layer and G organic light emitting layer have different wavelength characteristics, the optimum optical distance is different. For example, in the case of the same order m, the film thickness of the R organic light emitting layer having a long wavelength is larger than the film thickness of the G organic light emitting layer.

  It should be noted that a shadow mask corresponding to each arrangement may be used for separately coating each R / G light emitting layer, and there is no problem even if another method such as a laser transfer method is used.

  On the cathode electrode 17, a B organic light emitting layer 18 composed of an electron injection layer, an electron transport layer, a light emitting layer, and a hole transport layer is formed in the order of the layers. Finally, transparent electrodes 19 and 20 are formed separately as anode electrodes. The B organic light emitting layer 18 is formed in common over all the pixels. This eliminates the need for separate painting using a shadow mask and simplifies the process.

  Here, the film thickness of each R • G organic light emitting layer serving as a base of the B organic light emitting layer is different as described above. Therefore, the optical distance L3 between the light emitting region of the B organic light emitting layer and the first anode electrode 14 and the optical distance L4 between the B organic light emitting layer and the first anode electrode 13 are necessarily different. Since the wavelength λ of the B organic light emitting layer is as short as 450 nm, when L3 and L4, which are the distance between the light emitting region and the reflective electrode in the B organic light emitting layer, are compared, L3 is strengthening effect by the reflective electrode. Easy to get. Therefore, the following description will be made on the assumption that the film thickness of the B organic light emitting layer is designed so that L3 satisfies the above expression (1).

(Description of pixel circuit operation)
FIG. 1 shows an example of a pixel circuit for driving the element configuration of FIG.

EL elements 7, 8, 9 and 10 in FIG. 1 respectively indicate the R light-emitting element, the B ₁ light-emitting element, the G light-emitting element, and the B ₂ light-emitting element formed as described in FIG. Each common terminal is connected to the switches Q3R and Q3B1 of the pixel circuits 3 and 4 through the tap 1 and to the switches Q3B2 and Q3G of the pixel circuits 5 and 6 through the tap 2.

  FIG. 3 is a sequence for driving the pixel circuit of FIG. 1, and shows a temporal order of programming display of each pixel in the organic EL display device according to the first embodiment.

Each row is sequentially selected from row (1) to row (n), and programming of each row is performed. At that time, two video signals are programmed corresponding to the light emission in the A light emission period and the B light emission period. After that, there is an A emission period, followed by a B emission period. In this embodiment, the A light emitting period emit R light emitting device and the G light emitting device, the B light emitting period B ₂ emits light.

  The drive sequence for one frame is in the order of a program period programmed in each row (row (1) to row (n)), an A emission period after the end of each row program period, and a B emission period, and this sequence is repeated in units of frames. .

  In FIG. 3, the light emission unit of the A light emission period and the B light emission period is once, but the light emission periods of A and B may be shortened and repeated alternately until the next program period.

  FIG. 2 is a timing chart showing the operation of the pixel circuit. In FIG. 1, Pa, Pb, and P1 indicate the drive timing of the control line in FIG. 1, and Vc indicates the drive timing of the power supply line in FIG. Further, Va is a power supply Vcc, and Vb is a ground GND.

  In the period from t1 to t2 (program period in FIG. 3), the switches Q2R, Q2G, Q2B1, and Q2B2 of the pixel circuits 3, 4, 5, and 6 are turned on, and the video signals are output from the data lines data_r, data_g, data_b1, and data_b2. Are charged in the capacitors C1R, C1G, C1B1, and C1B2. Each data line data_r, data_g, data_b1, and data_b2 generates a voltage corresponding to the programming of the next row in FIG. 3 in the same period as that of t1 to t2 after the period of t1 to t2.

  In a period from t2 to t3 (A light emission period in FIG. 3), Q3R and Q3G are turned on by the control line Pa, and a signal current flows from the drive transistors Q1R and Q1G to the light emitting elements 7 and 9. In the period from t1 to t3, Va is at the power supply Vcc and Vc is at the ground potential, so that the light emitting elements 7 and 9 are in the light emitting state.

  In the period from t3 to t4, Q3B1 and Q3B2 are turned ON by the control line Pb, and a signal current flows from the driving transistors Q1B1 and Q1B2 to the light emitting elements 8 and 10. In the period from t3 to t4, Va is at the ground potential and Vc is at the power source Vcc, so that the light emitting elements 8 and 10 are in a light emitting state.

That is, the RB ₁ GB ₂ light emitting elements, which are the light emitting elements 7, 8, 9, and 10, are independently controlled based on the input data signal.

(Description of data line control block)
An example of a control system for the data lines data_r, data_g, data_b1, and data_b2 is shown in FIG.

  The serial data input to the display system in the order of N-bit RGB is input to the parallel data separation unit, and is separated into N-bit digital data of R data, G data, and B data and output. Further, the RGB serial data is input to the luminance calculation unit, and the Y data output from the luminance calculation unit uses a coefficient for calculating a general luminance such as R × 0.3 + G × 0.6 + B × 0.1. It is calculated.

  R data and G data are respectively input from the γ correction unit to the contrast adjustment unit, and white balance adjustment is performed for each color. Then, the D / A unit converts the digital data into analog data. In the AMP unit, analog data is appropriately amplified in accordance with the output gain of each driving transistor, and an analog voltage is supplied to the data line.

  In the B data, the white balance is adjusted by the contrast adjustment unit from the γ correction unit and then input to the B1 and B2 data conversion units. In the B1 and B2 data conversion units, for example, predetermined reference luminance data x is set for the Bc data output from the contrast unit, and compared with the luminance Y data output from the luminance calculation unit.

  If the luminance Y data is smaller than the reference luminance data x, B1 = 0 and B2 = Bc, and B1 = z and B2 = Bc−z (z <= Bc) for values exceeding the reference luminance data x. Perform the operation. Similar to the control of the R and G data, the D / A section converts the digital data into analog data. The AMP unit appropriately amplifies analog data in accordance with the output gain of each driving transistor, and supplies an analog voltage to the data lines (data_b1, data_b2).

  Note that the B1 and B2 data converters can easily change the settings of the reference luminance data x and the coefficient z in accordance with the chromaticity or light emission efficiency of the light emitting elements 8 and 10.

As described above, according to the first embodiment, the following control is performed in the stacked organic EL display device formed as a layer common to all pixels without separately coating one organic light emitting layer. Display without color misregistration can be performed.
(1) The integrated luminance value on the display screen is processed.
(2) When the calculated luminance value is equal to or less than an arbitrarily set threshold value, _{one of the} light emitting elements (B ₁ light emitting element, B ₂ light emitting element) including a common organic light emitting layer in each subpixel is controlled to emit no light. (Luminance 0). In other words, in the case of a luminance value that tends to cause a change in the color appearance of the display image, the light emitting element that is not formed at the optimal optical distance (the light emitting element B ₁ in the present embodiment) is made non-light emitting, and the color change is changed. I try not to make it happen.
(3) When the calculated luminance value exceeds the arbitrarily set threshold value, the luminance value is distributed among the light emitting elements including the common organic light emitting layer in each sub-pixel to emit light from each light emitting element. Control. That is, in the case of a luminance value that hardly causes a change in the color appearance of the display image, the luminance data is distributed to the light emitting elements that are not formed at the optimum optical distance (in this embodiment, the light emitting element B ₁ ) to emit light. . As a result, the emission intensity of the B light-emitting element formed on the G light-emitting element can be suppressed to extend the life and reduce the image sticking problem.

(Embodiment 2)
FIG. 8 shows another example of the control system for the data lines data_r, data_g, data_b1, and data_b2.

  The serial data input to the display system in the order of N-bit RGB is input to the parallel data separation unit, and is separated into N-bit digital data of R data, G data, and B data and output. In the present embodiment, G data converted into parallel data is input to the luminance calculation unit, and luminance Y data is extracted from luminance information of the G field.

As described above, the G pixel outputs about 60% of luminance when each RGB emission color is handled as the luminance value Y. Therefore, in the second embodiment, it is possible to efficiently grasp the entire luminance information and perform the non-light emission control of the B ₁ light emitting element by a light-weight calculation process with only G data.

In the above-described embodiment, the non-light emission control of the B ₁ light emitting element whose optical distance is not optimal is calculated by comparing the luminance of the entire display screen (for one frame) or a partial area with the reference luminance value x. The luminance value in pixel units may be compared with the reference luminance value x and controlled for each pixel.

  In the above-described embodiment, the description has been made in the form in which the B organic light emitting layer is formed in common. However, the same applies to the case where the R organic light emitting layer or the G organic light emitting layer is formed in common.

(Embodiment 3)
The third embodiment is the same as the first embodiment in that the B organic light emitting layer is formed as a common layer across all pixels, but after forming the B organic light emitting layer, the R organic light emitting layer and the G organic light emitting layer are formed. Are formed separately. Note that a detailed description of the driving circuit and the control method is omitted because the same method as in the first embodiment can be used.

  FIG. 9 schematically shows a cross-sectional structure of one pixel of the organic EL display device according to the third embodiment. 6 are the same as those in FIG. 6, and the description thereof is omitted here.

In FIG. 9, 21 is a reflective first cathode electrode (for B ₁ / B ₂ light emitting element) which is a lower electrode, 22 is a first anode electrode and second cathode electrode (for B ₁ / R light emitting element), 23 Denotes a first anode electrode / second cathode electrode 2 (for a B ₂ / G light emitting element), and 24 denotes a second anode electrode.

  A TFT (thin film transistor) (not shown) is formed on the glass substrate 11, and an insulating layer is formed to protect the TFT (thin film transistor). Subsequently, an organic planarization layer 12 is formed to planarize the irregularities generated by the TFT formation.

  A contact hole is formed in the organic planarization layer 12 to make electrical contact with each common electrode terminal formed on the glass substrate, and then the first cathode electrode 21 is formed.

  Note that either wet process or dry process may be used for manufacturing the electrode.

  After UV / ozone cleaning as pretreatment, vacuum baking is performed to form an organic light emitting layer on the substrate.

On the first cathode electrode (for B ₁ pixel) 21, an electron injection layer and an electron transport layer are sequentially formed, and a B light emitting layer and a hole transport layer are sequentially formed.

Subsequently, in order to make electrical contact with each drain terminal of the TFT formed on the glass substrate, the first and second cathode electrode (for B ₁ / R light emitting element) 22 and the first An anode / second cathode electrode (for B ₂ / G light emitting element) 23 is formed.

  Here, each of the anode and second cathode electrodes 22 and 23 may be selectively formed by a shadow mask method, or may be patterned by a laser or the like after the electrodes are uniformly formed in the display region. Also good.

  After forming an electron injection layer and an electron transport layer on the first anode / second cathode electrodes 22 and 23 as the second organic light emitting layer, on the first anode / second cathode electrode 22 Forms an R light emitting layer and a G light emitting layer on the first anode electrode / second cathode electrode 23, respectively.

  After each R / G light emitting layer, a hole transport layer is formed, and then a transparent electrode is formed as the second anode electrode 24 which is a common electrode.

  FIG. 10 is a schematic diagram showing the optical distance between the first cathode electrode, which is a reflective electrode, and the second anode electrode from the light emitting region of the B organic light emitting layer in each subpixel in the present embodiment.

In the present embodiment, since the B organic light emitting layer is formed as the first organic light emitting layer, the reflecting electrode extends from the light emitting region of the B organic light emitting layer in each of the subpixels indicated by L5 and L6 in FIG. The distance to is not changed. Further, when the first organic light emitting layer is a common layer, the optical distances on the reflective electrode side of the second organic light emitting element and the G light emitting element can be independently adjusted by the film thickness. . Therefore, in the case of this element configuration, good color sight can be realized with each of the R light emitting element, the B ₁ light emitting element, the G light emitting element, and the B ₂ light emitting element. However, the optical distances L7 and L8 from the light emitting region of the B organic light emitting layer to the second anode electrode 24 are different for each subpixel. The interference effect using the reflection at the reflection interface on the second anode electrode side, which is the upper electrode, is weaker than the interference effect using the primary reflection on the reflection electrode side, but has a considerable influence on the overall interference effect. . In particular, blue is more susceptible to the influence of other colors at a short wavelength. Therefore, if finding a higher quality, it can not be ignored changes in trials of B ₁ emitting element and B ₂ light-emitting element in this case.

Accordingly, in the present embodiment, as in the first embodiment, the B ₁ light emitting element is controlled to emit no light according to the luminance value, or the luminance value is distributed between the B ₁ light emitting element and the B ₂ light emitting element. The light emission is controlled. In this case, it is assumed that the optical distance L7 of the B ₂ light emitting element stacked with the G light emitting element is optimized.

It is a figure which shows an example of the pixel circuit of Embodiment 1 of this invention. 2 is a timing chart illustrating the operation of FIG. 1. It is a figure which shows the drive sequence of Embodiment 1 of this invention. It is a figure which shows schematic structure of the display panel of Embodiment 1 of this invention. It is a figure which shows the data conversion block of Embodiment 1 of this invention. It is a figure which shows typically the pixel cross section of Embodiment 1 of this invention. It is a figure which shows typically the optical distance of the pixel cross section of Embodiment 1 of this invention. It is a figure which shows the data conversion block of Embodiment 2 of this invention. It is a figure which shows typically the pixel cross section of Embodiment 3 of this invention. It is a figure which shows typically the optical distance of the pixel cross section of Embodiment 3 of this invention.

Explanation of symbols

3, 4, 5, 6 Pixel circuit 7, 8, 9, 10 Light emitting element 11 Glass substrate 12 Flattening layer 13 First anode electrode 1 (for R pixel)
14 First anode electrode 2 (for G pixel)
15 R light emitting layer 16 G light emitting layer 17 Cathode layer 18 B light emitting layer 19 Second anode electrode 1 (for B pixel)
20 Second anode electrode 2 (for B pixel)
21 First cathode electrode (for B pixel)
22 1st anode electrode and 2nd cathode electrode 1
23. First anode electrode / second cathode electrode 2
24 Second anode electrode

Claims (8)

  The pixel includes at least one pixel, and the pixel includes two sub-pixels. The sub-pixel includes two layers of light-emitting elements each including an organic light-emitting layer including at least a light-emitting layer sandwiched between electrodes. In the organic EL display device in which each light emitting layer emits light by applying a voltage between the electrodes of the light emitting element, one layer of the organic light emitting layer is formed in common over all pixels, and the common organic One of the light emitting elements of each subpixel including a light emitting layer is controlled to emit no light.   2. The organic EL display device according to claim 1, wherein the non-light emission control is performed when an integrated luminance value of a display screen is a predetermined threshold value or less.   2. The organic EL display device according to claim 1, wherein the non-emission control is performed for each pixel when a luminance value in one pixel is equal to or less than a predetermined threshold value.   The light emitting element includes a green light emitting element, and the non-light emission control is performed when an integrated luminance value of the green luminance data on a display screen is a predetermined threshold value or less. The organic EL display device according to claim 1.   The green light emitting element is included in the light emitting element, and the non-light emission control is performed for each pixel when the green luminance value in one pixel is equal to or less than a predetermined threshold. 1. The organic EL display device according to 1.   The organic EL display device according to claim 1, wherein the common organic light emitting layer is formed on the light extraction side with respect to another organic light emitting layer. 2. The organic EL display device according to claim 1, wherein each of the sub-pixels includes a reflective electrode as a lower electrode, and the light-emitting element controlled to emit no light does not satisfy the following condition.
2L / λ + δ / 2π = m
(In the formula, L is an optical distance between the light emitting region of the organic light emitting layer and the reflective surface of the reflective electrode, δ is a phase shift amount δ in the reflective electrode, and m is a natural number.)   6. The light emission control is performed by distributing the luminance value among light emitting elements of each sub-pixel including the common organic light emitting layer when the luminance value exceeds the threshold value. The organic EL display device described.

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