JP5127265B2 - Organic EL display device - Google Patents

Description

  The present invention relates to an organic electroluminescence (EL) display device.

  Flat display devices represented by liquid crystal display devices are rapidly growing in demand for CRT displays, taking advantage of the features of thinness, light weight and low power consumption. It has come to be used for various displays. In recent years, a display device using an organic electroluminescence (EL) element that is self-luminous, has a high response speed, a wide viewing angle, a high contrast, and can be reduced in thickness and weight as compared with a liquid crystal display device. Development is actively underway.

  An organic EL element injects holes from a hole injection electrode (anode) and electrons from an electron injection electrode (cathode) and recombines holes and electrons in a light emitting layer to obtain light emission. In this case, light emitting materials having different light emission spectra are used for the light emitting layers of the organic EL elements configured to have pixels that emit red (R), green (G), and blue (B), respectively. . In order to maximize the light emission efficiency of each of the RGB pixels in such a full color panel, it is necessary to design the film thickness according to the wavelength of the emission spectrum from the viewpoint of optical design. For example, light emitted from the light emitting layer includes light traveling to the anode side and light traveling to the cathode side, but one light is reflected by the anode or the cathode having reflection characteristics and causes interference with the other light. Here, if the film thickness of the organic EL element is appropriately designed, the optical interference can be optimized and light can be effectively extracted outside the element, so that the light emission efficiency can be maximized. Since the spectral wavelengths are different, the optimum film thickness of each RGB pixel is different.

  In order to realize this, generally, the film thickness of the hole transport layer (HTL) or the electron transport layer (EML), which has the least influence on the electrical characteristics, is changed for each RGB pixel to optimize the interference condition. . However, this method is not preferable because HTL vapor deposition or ETL vapor deposition is required three times for each RGB pixel, which increases the number of process steps.

On the other hand, when HTL and EML are made common to each RGB pixel, it is necessary to change the thickness of the light emitting layer for each RGB pixel. In this case, the layers other than one of the light emitting layers of RGB must be deposited so as to be extremely thicker than the minimum film thickness necessary for light emission, which is not preferable because the amount of material used is more than necessary.
JP 2003-157773 A

  The object of the present invention is to prevent the increase in the number of processes and the amount of material used, and optimize the film thickness of each RGB pixel so that each efficiency is maximized. Another object of the present invention is to provide a low-power full-color organic EL display device.

According to a first aspect of the present invention, an insulating substrate, a scanning signal line located above the insulating substrate, and first and second images located above the insulating substrate, each intersecting the scanning signal line. A signal line, a first transistor and a second transistor arranged above the insulating substrate , corresponding to intersections of the scanning signal line and the first and second video signal lines, respectively, and above the insulating substrate. First and second pixel electrodes arranged corresponding to the first and second transistors, the scanning signal line, the first and second video signal lines, and the first and second transistors, respectively. An opening is formed at the position of the first and second pixel electrodes, and a portion corresponding to a region between the first and second pixel electrodes is perpendicular to the arrangement direction of the first and second pixel electrodes. and the partition insulating layer section is tapered such, the 1 and a counter electrode formed over the second pixel electrode and the partition insulating layer, a portion is interposed between the counter electrode and the first pixel electrode, the other part of the second pixel electrode Corresponding to the second pixel electrode of the first and second pixel electrodes, and a first light-emitting layer that extends over the region including the first and second pixel electrodes. A second light emitting layer which is provided only in the region and overlaps with the first light emitting layer between the second pixel electrode and the counter electrode, and is sandwiched between the first pixel electrode and the counter electrode. Thus, an organic EL display device is provided in which an optical resonator is formed with the portion, and an optical resonator is formed with the second pixel electrode, the counter electrode, and a portion sandwiched therebetween.

According to a second aspect of the present invention, an insulating substrate, a scanning signal line located above the insulating substrate, and first to third images located above the insulating substrate, each intersecting the scanning signal line. A first signal line, a first transistor, a third transistor, a first transistor, and a third transistor arranged in correspondence with an intersection of the scanning signal line and the first to third video signal lines; Positioned above the first to third pixel electrodes arranged corresponding to the first to third transistors, the scanning signal lines, the first to third video signal lines, and the first to third transistors, respectively. An opening is formed at the position of the first to third pixel electrodes, and a portion corresponding to a region between the first and second pixel electrodes is perpendicular to the arrangement direction of the first and second pixel electrodes. The second section and the third section are tapered Portion corresponding to the region between the electrodes, and the partition insulating layer being tapered cross section perpendicular to the arrangement direction of the second and third pixel electrodes, the first to third pixel electrodes and the partition insulating layer A part of the counter electrode formed between the first pixel electrode and the counter electrode, and the other part of the counter electrode interposed between the second pixel electrode and the counter electrode. Further, another part is interposed between the third pixel electrode and the counter electrode, and spreads over a region including the first to third pixel electrodes, and the first to third Among the pixel electrodes, the first light emitting layer is provided only in a region corresponding to the second pixel electrode or a region corresponding to the second and third pixel electrodes, and at least between the second pixel electrode and the counter electrode. A second light emitting layer overlapping with the third pixel electrode, and the third image of the first to third pixel electrodes. It provided only in a region corresponding to the electrode, comprising a third light-emitting layer overlapping with the first light-emitting layer between the counter electrode and the third pixel electrode, and the first pixel electrode and the counter electrode The portion sandwiched between them constitutes an optical resonator, the second pixel electrode, the counter electrode, and the portion sandwiched therebetween constitute an optical resonator, and the third pixel electrode, the counter electrode, An organic EL display device constituting an optical resonator is provided with a portion sandwiched between them .

According to a third aspect of the present invention, there are provided an insulating substrate, and first to third video signal lines extending in a first direction and arranged in a second direction intersecting the first direction above the insulating substrate. A plurality of scanning signal lines intersecting with the first to third video signal lines above the insulating substrate; and an intersection of the plurality of scanning signal lines and the first video signal line above the insulating substrate. A plurality of first transistors arranged corresponding to the plurality of second transistors arranged above the insulating substrate so as to correspond to intersections of the plurality of scanning signal lines and the second video signal line; A plurality of third transistors arranged corresponding to intersections of the plurality of scanning signal lines and the third video signal line above the insulating substrate, and a plurality of first transistors above the insulating substrate. Correspondingly, a plurality of first pixel electrodes arranged in the first direction. And a plurality of second pixel electrodes arranged in the first direction corresponding to the plurality of second transistors above the insulating substrate, and in the second direction with respect to the first column And a plurality of third pixel electrodes arranged in the first direction corresponding to the plurality of third transistors above the insulating substrate, and the second column is adjacent to the second column. A third column adjacent in two directions, the plurality of scanning signal lines, the plurality of first to third video signal lines, and the plurality of first to third transistors, Openings are made at the positions of the first to third pixel electrodes, and the section corresponding to the region between the first and second pixel electrodes has a tapered cross section perpendicular to the arrangement direction of the first and second pixel electrodes. The portion corresponding to the region between the second and third pixel electrodes is A partition insulating layer having a tapered cross section perpendicular to the arrangement direction of the second and third pixel electrodes; a counter electrode formed above the first to third columns and the partition insulating layer; A first light emitting layer interposed between the first to third rows and the counter electrode and extending over a region including the first to third rows; and a shape extending in the first direction; A second light emitting layer provided only in a region corresponding to the second column of the first to third columns, and overlapping the first light emitting layer between the second column and the counter electrode; The first light emitting layer has a shape extending in one direction and is provided only in a region corresponding to the third column of the first to third columns, and between the third column and the counter electrode, Each of the plurality of first pixel electrodes, the counter electrode, and a portion sandwiched between the third light emitting layers, Constitutes an optical resonator, and each of the plurality of second pixel electrodes, the counter electrode, and a portion sandwiched between them constitute an optical resonator, and are opposed to each of the plurality of third pixel electrodes. An organic EL display device in which an electrode and a portion sandwiched between the electrodes constitute an optical resonator is provided.

According to a fourth aspect of the present invention, there are provided an insulating substrate, and first to third video signal lines extending in the first direction above the insulating substrate and arranged in a second direction intersecting the first direction. A plurality of scanning signal lines intersecting with the first to third video signal lines above the insulating substrate; and an intersection of the plurality of scanning signal lines and the first video signal line above the insulating substrate. A plurality of first transistors arranged corresponding to the plurality of second transistors arranged above the insulating substrate so as to correspond to intersections of the plurality of scanning signal lines and the second video signal line; A plurality of third transistors arranged corresponding to intersections of the plurality of scanning signal lines and the third video signal line above the insulating substrate, and a plurality of first transistors above the insulating substrate. Correspondingly, a plurality of first pixel electrodes arranged in the first direction. And a plurality of second pixel electrodes arranged in the first direction corresponding to the plurality of second transistors above the insulating substrate, and in the second direction with respect to the first column And a plurality of third pixel electrodes arranged in the first direction corresponding to the plurality of third transistors above the insulating substrate, and the second column is adjacent to the second column. A third column adjacent in two directions, the plurality of scanning signal lines, the plurality of first to third video signal lines, and the plurality of first to third transistors, Openings are made at the positions of the first to third pixel electrodes, and the section corresponding to the region between the first and second pixel electrodes has a tapered cross section perpendicular to the arrangement direction of the first and second pixel electrodes. The portion corresponding to the region between the second and third pixel electrodes is A partition insulating layer having a tapered cross section perpendicular to the arrangement direction of the second and third pixel electrodes; a counter electrode formed above the first to third columns and the partition insulating layer; A first light emitting layer interposed between the first to third rows and the counter electrode and extending over a region including the first to third rows; and a shape extending in the first direction; Of the first to third columns, provided only in regions corresponding to the second and third columns, and between the second column and the counter electrode and between the third column and the counter electrode, A second light-emitting layer overlapping the first light-emitting layer, and a shape extending in the first direction, provided only in a region corresponding to the third column in the first to third columns; A plurality of first pixel electrodes comprising a third light emitting layer overlapping the first light emitting layer between a column and the counter electrode; Each of the plurality of second pixel electrodes, the counter electrode, and the portion sandwiched between them constitute an optical resonator. In addition, an organic EL display device is provided in which each of the plurality of third pixel electrodes, the counter electrode, and a portion sandwiched therebetween constitute an optical resonator.

  According to the present invention, by preventing the increase in the number of processes and the amount of material used, and optimizing the film thickness of each RGB pixel so that each efficiency is maximized, it is highly productive and environmentally friendly. In addition, a low-power full-color organic EL display device can be provided.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, in each figure, the same referential mark is attached | subjected to the component which exhibits the same or similar function, and the overlapping description is abbreviate | omitted.

  FIG. 1 is a plan view schematically showing an organic EL display device according to an aspect of the present invention. FIG. 2 is a cross-sectional view schematically showing an example of a structure that can be employed in the display device of FIG. FIG. 3 is a cross-sectional view schematically showing an example of a structure that can be employed in the organic EL element included in the display device of FIG. FIG. 4 is a plan view schematically showing an example of the arrangement of the light emitting layers that can be employed in the display device of FIG.

  The display device of FIGS. 1 and 2 is a top emission type organic EL display device adopting an active matrix driving method. This display device includes a display panel DP, a video signal line driver XDR, and a scanning signal line driver YDR.

As illustrated in FIGS. 1 and 2, the display panel DP includes an insulating substrate SUB such as a glass substrate, for example. An undercoat layer (not shown) is formed on the substrate SUB. The undercoat layer is formed, for example, by laminating a SiN _x layer and a SiO _x layer in this order on the substrate SUB.

  On the undercoat layer, for example, a semiconductor pattern made of polysilicon containing impurities is formed. A part of this semiconductor pattern is used as the semiconductor layer SC of FIG. Impurity diffusion regions used as a source and a drain are formed in the semiconductor layer SC. Further, another part of the semiconductor pattern is used as a lower electrode of a capacitor C described later. The lower electrodes are arranged corresponding to pixels PX1 to PX3 described later.

  Note that the pixels PX1 to PX3 are arranged in this order in the X direction to form a triplet. In the display area, the triplets are arranged in the X direction and the Y direction. That is, in the display area, a pixel column in which the pixels PX1 are arranged in the Y direction, a pixel column in which the pixels PX2 are arranged in the Y direction, and a pixel column in which the pixels PX3 are arranged in the Y direction are arranged in this order in the X direction. In addition, these three pixel columns are repeatedly arranged in the X direction.

  The semiconductor pattern is covered with the gate insulating film GI shown in FIG. The gate insulating film GI can be formed using, for example, TEOS (tetraethyl orthosilicate).

  On the gate insulating film GI, the scanning signal lines SL1 and SL2 shown in FIG. 1 are formed. The scanning signal lines SL1 and SL2 each extend in the X direction and are alternately arranged in the Y direction. The scanning signal lines SL1 and SL2 are made of, for example, MoW.

  An upper electrode of the capacitor C is further disposed on the gate insulating film GI. The upper electrode is arranged corresponding to the pixels PX1 to PX3, and faces the lower electrode. The upper electrode is made of, for example, MoW and can be formed in the same process as the scanning signal lines SL1 and SL2.

  The scanning signal lines SL1 and SL2 intersect the semiconductor layer SC. The intersection of the scanning signal line SL1 and the semiconductor layer SC constitutes the switching transistor SWa shown in FIGS. 1 and 2, and the intersection of the scanning signal line SL2 and the semiconductor layer SC is the switching transistor SWb shown in FIG. SWc is configured. Moreover, the lower electrode, the upper electrode, and the insulating film GI interposed therebetween constitute the capacitor C shown in FIG. The upper electrode includes an extension that intersects with the semiconductor layer SC, and the intersection between the extension and the semiconductor layer SC forms the drive transistor DR shown in FIG.

  In this example, the drive transistor DR and the switching transistors SWa to SWc are top-gate p-channel thin film transistors. Further, the portion indicated by reference numeral G in FIG. 2 is the gate of the switching transistor SWa.

The gate insulating film GI, the scanning signal lines SL1 and SL2, and the upper electrode are covered with an interlayer insulating film II shown in FIG. The interlayer insulating film II is made of, for example, SiO _x deposited by plasma CVD (chemical vapor deposition).

  On the interlayer insulating film II, the video signal line DL and the power supply line PSL shown in FIG. 1 are formed. As shown in FIG. 1, each video signal line DL extends in the Y direction and is arranged in the X direction. For example, each of the power supply lines PSL extends in the Y direction and is arranged in the X direction.

  On the interlayer insulating film II, the source electrode SE and the drain electrode DE shown in FIG. 2 are further formed. The source electrode SE and the drain electrode DE connect elements in each of the pixels PX1 to PX3.

  The source electrode SE and the drain electrode DE are connected to an impurity diffusion region provided in the semiconductor layer SC by a contact hole opened in the interlayer insulating film II.

  The video signal line DL, the power supply line PSL, the source electrode SE, and the drain electrode DE have, for example, a three-layer structure of Mo / Al / Mo. These can be formed in the same process.

The video signal line DL, the power supply line PSL, the source electrode SE, and the drain electrode DE are covered with a passivation film PS shown in FIG. The passivation film PS is made of, for example, SiN _x .

  On the passivation film PS, the pixel electrodes PE shown in FIG. 2 are arranged corresponding to the pixels PX1 to PX3. Each pixel electrode PE is connected to the drain electrode DE through a contact hole provided in the passivation film PS, and this drain electrode is connected to the drain of the switching transistor SWa.

  The pixel electrode PE is a back electrode in this example. Further, the pixel electrode PE is an anode in this example. As a material of the pixel electrode PE, for example, a transparent conductive oxide such as ITO (indium tin oxide) can be used. In this case, typically, as shown in FIG. 3, a reflective layer REF made of a metal material such as aluminum is disposed between the pixel electrode PE and the substrate SUB.

  A partition insulating layer PI shown in FIG. 2 is further formed on the passivation film PS. In the partition insulating layer PI, a through hole is provided at a position corresponding to the pixel electrode PE, or a slit is provided at a position corresponding to a column formed by the pixel electrode PE. Here, as an example, the partition insulating layer PI is provided with a through hole at a position corresponding to the pixel electrode PE.

  The partition insulating layer PI is, for example, an organic insulating layer. The partition insulating layer PI can be formed using, for example, a photolithography technique.

  An organic layer ORG is formed on each pixel electrode PE. As shown in FIG. 2, the organic layer ORG is typically a continuous film extending over the display area including all the pixels PX1 to PX3. That is, typically, the organic layer ORG covers the pixel electrode PE and the partition insulating layer PI.

  As shown in FIG. 3, a portion of the organic layer ORG corresponding to the pixel electrode PE of the pixel PX1 includes a light emitting layer EML1. A portion of the organic layer ORG corresponding to the pixel electrode PE of the pixel PX1 may further include a hole transport layer HTL between the pixel electrode PE and the light emitting layer EML1. In addition, a portion of the organic layer ORG corresponding to the pixel electrode PE of the pixel PX1 can further include an electron transport layer ETL between the light emitting layer EML1 and a counter electrode CE described later.

  A portion of the organic layer ORG corresponding to the pixel electrode PE of the pixel PX2 includes a light emitting layer EML1 and a light emitting layer EML2. The light emitting layer EML2 is interposed between the pixel electrode PE and the light emitting layer EML1. A portion of the organic layer ORG corresponding to the pixel electrode PE of the pixel PX2 may further include a hole transport layer HTL between the pixel electrode PE and the light emitting layer EML2. In addition, a portion of the organic layer ORG corresponding to the pixel electrode PE of the pixel PX2 may further include an electron transport layer ETL between the light emitting layer EML1 and the counter electrode CE.

  A portion of the organic layer ORG corresponding to the pixel electrode PE of the pixel PX3 includes a light emitting layer EML1 and a light emitting layer EML3. The light emitting layer EML3 is interposed between the pixel electrode PE and the light emitting layer EML1. A portion of the organic layer ORG corresponding to the pixel electrode PE of the pixel PX3 may further include a hole transport layer HTL between the pixel electrode PE and the light emitting layer EML3. In addition, a portion of the organic layer ORG corresponding to the pixel electrode PE of the pixel PX3 may further include an electron transport layer ETL between the light emitting layer EML1 and the counter electrode CE.

  The light emitting layer EML1 is a thin film containing a luminescent organic compound or composition whose emission color is blue. The light emitting layer EML1 is made of, for example, a mixture of a host material and a dopant material. For example, the light emitting layer EML1 is arranged in the X direction and the Y direction corresponding to the pixels PX1 to PX3. Alternatively, the light emitting layer EML1 has a band shape extending in the Y direction, and is arranged in the X direction corresponding to the columns of the pixels PX1 to PX3. Alternatively, as shown in FIG. 4, the light emitting layer EML1 is a continuous film extending over the display area including all the pixels PX1 to PX3. As an example, the light emitting layer EML1 is assumed to be a continuous film.

  The light emitting layer EML2 is a thin film containing a luminescent organic compound or composition whose emission color is green. The light emitting layer EML2 is made of, for example, a mixture of a host material and a dopant material. For example, the light emitting layer EML2 is arranged in the X direction and the Y direction corresponding to the pixel PX2. Alternatively, as shown in FIG. 4, the light emitting layer EML2 has a band shape extending in the Y direction, and is arranged in the X direction corresponding to the column of the pixels PX2. As an example, the light emitting layer EML2 is assumed to have the latter structure.

  The light emitting layer EML3 is a thin film containing a luminescent organic compound or composition whose emission color is red. The light emitting layer EML3 is made of, for example, a mixture of a host material and a dopant material. For example, the light emitting layer EML3 is arranged in the X direction and the Y direction corresponding to the pixel PX3. Alternatively, as shown in FIG. 4, the light emitting layer EML3 has a band shape extending in the Y direction, and is arranged in the X direction corresponding to the column of the pixels PX1. As an example, it is assumed that the light emitting layer EML3 has the latter structure.

  Note that the color of light having a wavelength in the range of 400 nm to 435 nm is purple, the color of light having a wavelength in the range of 435 nm to 480 nm is blue, the color of light having a wavelength in the range of 480 nm to 490 nm is patina, The color of light with a wavelength in the range of 490 nm to 500 nm is blue-green, the color of light with a wavelength in the range of 500 nm to 560 nm is green, the color of light with a wavelength in the range of 560 nm to 580 nm is yellow-green, The color of light having a wavelength in the range of 580 nm to 595 nm is yellow, the color of light having a wavelength in the range of 595 nm to 610 nm is orange, the color of light having a wavelength in the range of 610 nm to 750 nm is red, and the wavelength is Generally, the color of light in the range of 750 nm to 800 nm is defined as magenta. Here, the color of light having a dominant wavelength in the range of 400 nm to 490 nm is blue, the color of light having a dominant wavelength longer than 490 nm and shorter than 595 nm is green, and the light having a dominant wavelength in the range of 595 nm to 800 nm. The color is defined as red.

  The hole transport layer HTL and the electron transport layer ETL are typically continuous films extending over the display region. The hole transport layer HTL and the electron transport layer ETL may be patterned, for example, corresponding to the pixels PX1 to PX3 or corresponding to their rows or columns.

  The organic layer ORG further includes an electron blocking layer between the hole transport layer HTL and the light emitting layer EML1, between the hole transport layer HTL and the light emitting layer EML2, and between the hole transport layer HTL and the light emitting layer EML3. Can be included. The organic layer ORG may further include a hole blocking layer between the light emitting layer EML3 and the electron transport layer ETL. The electron blocking layer and the hole blocking layer are typically continuous films extending over the display region. The electron blocking layer and the hole blocking layer may be patterned, for example, corresponding to the pixels PX1 to PX3 or corresponding to their rows or columns.

  The partition insulating layer PI and the organic layer ORG are covered with the counter electrode CE. In this example, the counter electrode CE is a common electrode shared by the pixels PX1 to PX3. In this example, the counter electrode CE is a cathode and a light-transmitting front electrode, and an alloy thin film of magnesium Mg and silver Ag is used. The counter electrode CE is electrically connected to an electrode wiring (not shown) formed on the same layer as the video signal line DL through, for example, a contact hole provided in the passivation film PS and the partition insulating layer PI. It is connected.

  The pixel electrode PE, the organic layer ORG, and the counter electrode CE form an organic EL element OLED arranged in correspondence with the pixel electrode PE. In FIG. 4, reference numerals EA1 to EA3 indicate the light emitting portions of the organic EL elements OLED included in the pixels PX1 to PX3, respectively. Each of the light emitting units EA1 to EA3 is a right-angled quadrilateral extending in the Y direction. In the structure of FIG. 4, the areas of the light emitting portions EA1 to EA3 are equal to each other.

  As shown in FIG. 3, each organic EL element OLED may further include a hole injection layer HIL between the pixel electrode PE and the organic layer ORG. Each organic EL element OLED can further include an electron injection layer EIL between the organic layer ORG and the counter electrode CE. The hole injection layer HIL and the electron injection layer EIL are typically continuous films extending over the display region. The hole injection layer HIL and the electron injection layer EIL may be patterned, for example, corresponding to the pixels PX1 to PX3 or corresponding to their rows or columns.

  As shown in FIG. 1, each of the pixels PX1 to PX3 includes a drive transistor DR, switching transistors SWa to SWc, an organic EL element OLED, and a capacitor C. As described above, in this example, the drive transistor DR and the switching transistors SWa to SWc are p-channel thin film transistors. In this example, the organic EL element OLED included in the pixel PX1 emits blue light, the organic EL element OLED included in the pixel PX2 emits green light, and the organic EL element OLED included in the pixel PX3 emits red light.

  The drive transistor DR, the switching transistor SWa, and the organic EL element OLED are connected in series in this order between the first power supply terminal ND1 and the second power supply terminal ND2. In this example, the power supply terminal ND1 is a high potential power supply terminal, and the power supply terminal ND2 is a low potential power supply terminal.

  The gate of the switching transistor SWa is connected to the scanning signal line SL1. The switching transistor SWb is connected between the video signal line DL and the drain of the drive transistor DR, and its gate is connected to the scanning signal line SL2. The switching transistor SWc is connected between the drain and gate of the driving transistor DR, and the gate is connected to the scanning signal line SL2.

  The capacitor C is connected between the gate of the driving transistor DR and the constant potential terminal ND1 '. In this example, the constant potential terminal ND1 'is connected to the power supply terminal ND1.

  The video signal line driver XDR and the scanning signal line driver YDR are disposed on the substrate SUB. That is, the video signal line driver XDR and the scanning signal line driver YDR are mounted on COG (chip on glass). The video signal line driver XDR and the scanning signal line driver YDR may be mounted by TCP (tape carrier package) instead of COG mounting. Alternatively, the video signal line driver XDR and the scanning signal line driver YDR may be formed on the substrate SUB.

  A video signal line DL is connected to the video signal line driver XDR. In this example, a power supply line PSL is further connected to the video signal line driver XDR. The video signal line driver XDR outputs a current signal as a video signal to the video signal line DL and supplies a power supply voltage to the power supply line PSL.

  Scanning signal lines SL1 and SL2 are connected to the scanning signal line driver YDR. The scanning signal line driver YDR outputs voltage signals as first and second scanning signals to the scanning signal lines SL1 and SL2, respectively.

  When an image is displayed on this organic EL display device, for example, the scanning signal line SL2 is sequentially scanned. That is, the pixels PX1 to PX3 are selected for each row. In a selection period in which a certain row is selected, a writing operation is performed on the pixels PX1 to PX3 included in the row. In a non-selection period in which the row is not selected, display operation is performed on the pixels PX1 to PX3 included in the row.

In the selection period in which the pixels PX1 to PX3 in a certain row are selected, the scanning signal line driver YDR performs scanning (opens a non-conducting state) to open the switching transistor SWa to the scanning signal line SL1 to which the previous pixels PX1 to PX3 are connected. The signal is output as a voltage signal, and subsequently, a scanning signal that closes the switching transistors SWb and SWc (sets the conductive state) to the scanning signal line SL2 to which the previous pixels PX1 to PX3 are connected is output as a voltage signal. In this state, the video signal line driver XDR outputs the video signal to the video signal line DL as a current signal (write current) I _sig , and uses the gate-source voltage V _gs of the drive transistor DR as the previous video signal I. Set the size corresponding to _sig . Thereafter, the scanning signal line driver YDR outputs a scanning signal for opening the switching transistors SWb and SWc to the scanning signal line SL2 connected to the previous pixels PX1 to PX3 as a voltage signal, and then the previous pixels PX1 to PX3 A scanning signal for closing the switching transistor SWa is output as a voltage signal to the connected scanning signal line SL1. This ends the selection period.

In the non-selection period following the selection period, the switching transistor SWa remains closed and the switching transistors SWb and SWc remain open. In the non-selection period, a drive current I _drv having a magnitude corresponding to the gate-source voltage V _gs of the drive transistor DR flows through the organic EL element OLED. The organic EL element OLED emits light with a luminance corresponding to the magnitude of the drive current I _drv . Here, I _{drv ≈I sig} , and light emission corresponding to the current signal (write current) I _sig can be obtained in each pixel.

This organic EL display device can be manufactured, for example, by the following method.
First, a structure in which the counter electrode CE, the electron injection layer EIL, the organic material layer ORG, and the hole injection layer HIL are removed from the display panel DP described above, that is, an array substrate is prepared.

  Next, a hole injection layer HIL is formed on the pixel electrode PE. The hole injection layer HIL is, for example, a continuous film extending over the display region.

  Next, each layer included in the organic layer ORG is formed on the hole injection layer HIL by a vacuum deposition method. The light emitting layers EML2 and EML3 are formed by, for example, a vacuum evaporation method using a fine mask. The hole injection layer HIL, the hole transport layer HTL, the light emitting layer EML1, the electron transport layer ETL, and the electron injection layer EIL are formed by, for example, a vacuum evaporation method using a rough mask.

  In addition, as a fine mask used for formation of the light emitting layer EML2, what used the some slit formed corresponding to the light emitting layer EML2 is used, for example. Moreover, as a fine mask used for formation of the light emitting layer EML3, for example, a mask in which a plurality of slits are formed corresponding to the light emitting layer EML3 is used. As the previous rough mask, for example, a mask having an opening corresponding to the display area is used.

  Thereafter, an electron injection layer EIL and a counter electrode CE are sequentially formed on the electron transport layer ETL. Further, the organic EL element OLED is sealed, and the video signal line driver XDR and the scanning signal line driver YDR are mounted on the display panel DP. As described above, the organic EL display device of FIGS. 1 and 2 is obtained.

  By the way, when one organic EL element OLED includes the light emitting layer EML2 or EML3 and the light emitting layer EML1, not only the light emitting layer EML2 or EML3 but also the light emitting layer EML1 may emit light. In this case, the purity of the emission color of the pixel PX2 or PX3 is lowered.

  In order to prevent this, a design in which only the light-emitting layer EML2 of the light-emitting layers EML1 and EML2 emits light is adopted for the organic EL element OLED of the pixel PX2. Similarly, the organic EL element OLED of the pixel PX3 adopts a design in which only the light emitting layer EML3 emits light among the light emitting layers EML1 and EML3.

  For example, the electron mobility of the electron transport layer ETL is made larger than the hole mobility of the hole transport layer HTL. In the organic EL element OLED of the pixel PX2, the barrier against electrons at the interface between the electron transport layer ETL and the light emitting layer EML1 is more compared to the hole barrier at the interface between the hole transport layer HTL and the light emitting layer EML2. Make it smaller. Further, in the organic EL element OLED of the pixel PX3, the barrier against electrons at the interface between the electron transport layer ETL and the light emitting layer EML1 is more compared to the hole barrier at the interface between the hole transport layer HTL and the light emitting layer EML3. Make it smaller. In this way, the light emitting layer EML1 can be prevented from emitting light in the pixels PX2 and PX3.

  In the structure described above, the light emitting layer EML1 includes a luminescent organic compound or composition whose emission color is blue, and the light emission layers EML2 and EML3 include a luminescent organic compound or composition whose emission colors are green and red, respectively. Yes.

  However, the luminescent organic compounds or compositions whose emission colors are red and green may be excited by blue light and emit red and green, respectively. Therefore, when the structure described above is employed, even if the light emitting layer EML1 emits light from the organic EL elements OLED of the pixels PX2 and PX3, the purity of the emission color of the pixel PX2 or PX3 is unlikely to decrease.

  In addition, the structure in which the thin film containing a luminescent organic compound or composition having a blue emission color is used as the light emitting layer EML1 provides each organic EL element OLED with a function as an optical resonator as described below. But it is advantageous.

  In the structure of FIG. 3, the interface between the pixel electrode PE and the reflective layer REF and the interface between the electron transport layer ETL and the electron injection layer EIL reflect part of the light emitted from the light emitting layers EML1 to EML3. Therefore, if the optical path length between the reflective layer REF and the electron injection layer EIL is optimized, reflection interference is repeatedly generated in the organic EL element OLED, that is, the organic EL element OLED functions as an optical resonator. Can be given.

  The resonance wavelength of the optical resonator is determined based on the emission color required for the organic EL element OLED. In other words, the previous optical path length is determined based on the emission color required for the organic EL element OLED. Typically, the organic EL element OLED having a green emission color has a longer optical path length than the organic EL element OLED having a blue emission color, and the organic EL element OLED having a red emission color emits light. The previous optical path length is made longer than that of the organic EL element OLED whose color is green-blue.

  As is apparent from FIG. 3, the organic EL element OLED of the pixel PX1 has a shorter optical path length than the organic EL elements OLED of the pixels PX2 and PX3. Therefore, when a thin film containing a luminescent organic compound or composition having a blue emission color is used as the light emitting layer EML1, each organic EL element OLED can be used as an optical resonator without increasing the number of steps. Can be given functions.

  Further, when the organic EL element OLED of the pixel PX2 includes only the light emitting layer EML2 among the light emitting layers EML1 to EML3 and the organic EL element OLED of the pixel PX3 includes only the light emitting layer EML3 among the light emitting layers EML1 to EML3, In order to give the organic EL element OLED a function as an optical resonator, the light emitting layers EML2 and EML3 must be formed thicker. That is, in this case, more evaporation material is required to form the light emitting layers EML2 and EML3. On the other hand, in the structure of FIG. 3, the organic EL element OLED of the pixel PX2 includes the light emitting layers EML1 and EML2, and the organic EL element OLED of the pixel PX3 includes the light emitting layers EML1 and EML3. That is, these organic EL elements OLED include a plurality of light emitting layers. Therefore, when this structure is employed, the amount of evaporation material used for forming the light emitting layers EML2 and EML3 can be reduced.

  In the structure of FIG. 3, the thickness of the light emitting layer EML2 and the thickness of the light emitting layer EML3 are equal, but they may be different.

  FIG. 5 is a cross-sectional view schematically showing another example of a structure that can be employed in the organic EL element included in the display device of FIG. In this structure, the light emitting layer EML3 is thicker than the light emitting layer EML2. Therefore, the organic EL element OLED of the pixel PX3 has a longer optical path length than the organic EL element OLED of the pixel PX2. When this structure is employed, the degree of freedom in design is further increased in providing each organic EL element OLED with a function as an optical resonator.

  In the structure of FIG. 3, the pixel PX3 does not include the light emitting layer EML2, but the pixel PX3 may further include the light emitting layer EML2.

  FIG. 6 is a cross-sectional view schematically showing another example of a structure that can be employed in the organic EL element included in the display device of FIG. FIG. 7 is a plan view schematically showing an example of the arrangement of the light emitting layers that can be adopted in the display device of FIG. 2 when the structure of FIG. 6 is adopted in the organic EL element.

  In the structure of FIG. 6, the organic EL element OLED of the pixel PX3 further includes a light emitting layer EML2 between the light emitting layer EML1 and the light emitting layer EML3. When this structure is employed, the degree of freedom in design is further increased in providing each organic EL element OLED with a function as an optical resonator.

  In the structure of FIG. 6, the organic EL elements OLED of the pixels PX2 and PX3 include a plurality of light emitting layers. Therefore, when this structure is adopted, the amount of the evaporation material used for forming the light emitting layers EML2 and EML3 can be reduced as in the case where the structure of FIG. 3 is adopted.

  When the structure of FIG. 6 is adopted, the light emitting layer EML2 can be connected between the adjacent pixels PX2 and PX3. Therefore, for example, as shown in FIG. 7, the light-emitting layer EML2 can be a stripe pattern that is patterned so as to face a column formed by a pair of adjacent pixels PX2 and PX3.

Various modifications can be made to the structure of FIG. This will be described below.
FIG. 8 is a cross-sectional view showing a modification of the structure of FIG. The structure in FIG. 8 corresponds to a structure in which the hole injection layer HIL, the hole transport layer HTL, the electron injection layer EIL, and the electron transport layer ETL are omitted from the structure in FIG.

  When this structure is adopted, for example, the electron barrier at the interface between the counter electrode CE and the light emitting layer EML1 is smaller than the hole barrier at the interface between the pixel electrode PE and each of the light emitting layers EML1 to EML3. To do. That is, the minimum value of the forward bias to be applied between the electrodes PE and CE in order to cause the injection of electrons from the counter electrode CE to the organic layer ORG, and the injection of holes from the pixel electrode PE to the organic layer ORG. It is made smaller compared to the minimum value of the forward bias to be applied between the electrodes PE and CE in order to generate. Alternatively, the hole mobility of the light emitting layer EML2 is made smaller than its electron mobility, and the hole mobility of the light emitting layer EML3 is made smaller than its electron mobility. Alternatively, both of these designs are adopted.

  Thus, for example, in the pixel PX2, the density of excitons can be increased in the light emitting layer EML2 compared to the light emitting layer EML1, and in the pixel PX3, excitation in the light emitting layer EML3 compared to the light emitting layers EML1 and EML2. The density of the child can be increased. Therefore, the light emitting layer EML1 can be prevented from emitting light in the pixel PX2, and the light emitting layers EML1 and EML2 can be prevented from emitting light in the pixel PX3. The electron mobility of the light emitting layers EML1 to EML3 increases, for example, when the dopant concentration is lowered, and decreases when the dopant concentration is increased.

  FIG. 9 is a cross-sectional view showing another modification of the structure of FIG. The structure in FIG. 9 is the same as the structure in FIG. 8 except that the stacking order of the light emitting layers EML1 to EML3 is reversed.

  When this structure is adopted, for example, the hole barrier at the interface between the pixel electrode PE and the light emitting layer EML1 is made smaller than the electron barrier at the interface between the counter electrode CE and the light emitting layers EML1 to EML3. Alternatively, the hole mobility of the light emitting layer EML1 is made larger than its electron mobility, and the hole mobility of the light emitting layer EML2 is made larger than its electron mobility. Alternatively, both of these designs are adopted. This can suppress the light emission layer EML1 from emitting light in the pixel PX2, and can suppress the light emission layers EML1 and EML2 from emitting light in the pixel PX3.

  FIG. 10 is a cross-sectional view showing another modification of the structure of FIG. The structure of FIG. 10 is the same as the structure of FIG. 8 except that the counter electrode CE is covered with the optical matching layer MC.

  The optical matching layer MC is a light-transmitting layer, and optically matches a gas layer such as nitrogen in the gap between the insulating substrate SUB and the sealing substrate SUB2. The refractive index of the optical matching layer MC is substantially equal to the refractive index of the organic layer ORG. For example, as the optical matching layer MC, a transparent inorganic insulating layer such as a SiON layer, a transparent inorganic conductive layer such as an ITO layer, or a transparent organic layer such as a layer included in the organic layer ORG can be used. When the optical matching layer MC is used, the light extraction efficiency can be increased.

  FIG. 11 is a cross-sectional view showing another modification of the structure of FIG. The structure of FIG. 11 is the same as the structure of FIG. 9 except that the counter electrode CE is covered with the optical matching layer MC.

  FIG. 12 is a cross-sectional view showing another modification of the structure of FIG. The structure of FIG. 12 is the same as the structure of FIG. 6 except that the hole injection layer HIL and the electron injection layer EIL are omitted and the counter electrode CE is covered with the optical matching layer MC.

  When this structure is adopted, for example, the minimum value of the forward bias to be applied between the electrodes PE and CE in order to cause injection of electrons from the counter electrode CE to the electron transport layer ETL is determined from the pixel electrode PE to the hole. It is smaller than the minimum value of the forward bias to be applied between the electrodes PE and CE to cause the injection of holes into the transport layer HTL. Alternatively, the barrier against electrons at the interface between the electron transport layer ETL and the light emitting layer EML1 is made smaller than the hole barrier at the interface between the hole transport layer HTL and the light emitting layers EML1 to EML3. Alternatively, as a combination of the hole transport layer HTL and the electron transport layer ETL, a hole transport layer having a smaller hole mobility than that of the electron transport layer ETL is used. Alternatively, the hole mobility of the light emitting layer EML2 is made smaller than its electron mobility, and the hole mobility of the light emitting layer EML3 is made smaller than its electron mobility. Alternatively, two or more of these designs are employed. This can suppress the light emission layer EML1 from emitting light in the pixel PX2, and can suppress the light emission layers EML1 and EML2 from emitting light in the pixel PX3.

  FIG. 13 is a cross-sectional view showing another modification of the structure of FIG. The structure of FIG. 13 is the same as the structure of FIG. 12 except that the stacking order of the light emitting layers EML1 to EML3 is reversed.

  When this structure is adopted, for example, the minimum value of the forward bias to be applied between the electrodes PE and CE to cause the injection of holes from the pixel electrode PE to the hole transport layer HTL is determined from the counter electrode CE. It is smaller than the minimum value of the forward bias to be applied between the electrodes PE and CE in order to cause the injection of electrons into the electron transport layer ETL. Alternatively, the barrier against holes at the interface between the hole transport layer HTL and the light emitting layer EML1 is made smaller than the electron barrier at the interface between the electron transport layer ETL and the light emitting layers EML1 to EML3. Alternatively, as a combination of the hole transport layer HTL and the electron transport layer ETL, one having an electron mobility of the electron transport layer ETL smaller than that of the hole transport layer HTL is used. Alternatively, the hole mobility of the light emitting layer EML1 is made larger than its electron mobility, and the hole mobility of the light emitting layer EML2 is made larger than its electron mobility. Alternatively, two or more of these designs are employed. This can suppress the light emission layer EML1 from emitting light in the pixel PX2, and can suppress the light emission layers EML1 and EML2 from emitting light in the pixel PX3.

  FIG. 14 is a cross-sectional view showing another modification of the structure of FIG. The structure of FIG. 14 is the same as the structure of FIG. 6 except that the hole injection layer HIL is omitted and the counter electrode CE is covered with the optical matching layer MC.

  The structure of FIG. 14 uses the electron injection layer EIL and omits the hole injection layer HIL. Therefore, this structure has a minimum value of the forward bias to be applied between the electrodes PE and CE to cause the injection of electrons from the counter electrode CE to the electron transport layer ETL, and the pixel electrode PE to the hole transport layer HTL. It is advantageous to make it smaller compared to the minimum value of the forward bias to be applied between the electrodes PE and CE in order to cause the injection of holes into the electrode. Therefore, by adopting this structure, it is possible to more easily suppress the light emitting layer EML1 from emitting light in the pixel PX2, and to suppress the light emitting layers EML1 and EML2 from emitting light in the pixel PX3.

  FIG. 15 is a cross-sectional view showing another modification of the structure of FIG. The structure of FIG. 15 is the same as the structure of FIG. 14 except that the structure further includes an electron blocking layer EBL interposed between the hole transport layer HTL and the light emitting layers EML1 to EML3.

  This structure is similar to the structure of FIG. 14 in that the minimum value of the forward bias to be applied between the electrodes PE and CE to cause injection of electrons from the counter electrode CE to the electron transport layer ETL is determined from the pixel electrode PE. It is advantageous to make it smaller compared to the minimum value of the forward bias to be applied between the electrodes PE and CE in order to cause the injection of holes into the hole transport layer HTL. Further, when this structure is adopted, the electron density in the layer adjacent to the electron blocking layer EBL among the light emitting layers EML1 to EML3 is increased. Therefore, by adopting this structure, it is possible to more easily suppress the light emitting layer EML1 from emitting light in the pixel PX2, and to suppress the light emitting layers EML1 and EML2 from emitting light in the pixel PX3. In addition, when this structure is adopted, higher luminous efficiency can be realized.

  FIG. 16 is a cross-sectional view showing another modification of the structure of FIG. The structure of FIG. 16 is the same as the structure of FIG. 6 except that the stacking order of the light emitting layers EML1 to EML3 is reversed, the electron injection layer EIL is omitted, and the counter electrode CE is covered with the optical matching layer MC.

  The structure of FIG. 16 uses a hole injection layer HIL and omits the electron injection layer EIL. Therefore, this structure provides a minimum value of the forward bias to be applied between the electrodes PE and CE to cause the injection of holes from the pixel electrode PE to the hole transport layer HTL, and the counter electrode CE to the electron transport layer. It is advantageous to make it smaller compared to the minimum value of the forward bias to be applied between the electrodes PE and CE to cause the injection of electrons into the ETL. Therefore, by adopting this structure, it is possible to more easily suppress the light emitting layer EML1 from emitting light in the pixel PX2, and to suppress the light emitting layers EML1 and EML2 from emitting light in the pixel PX3.

  FIG. 17 is a cross-sectional view showing another modification of the structure of FIG. The structure of FIG. 17 is the same as the structure of FIG. 16 except that it further includes a hole blocking layer HBL interposed between the electron transport layer ETL and the light emitting layers EML1 to EML3.

  This structure is similar to the structure of FIG. 16 in that the minimum value of the forward bias to be applied between the electrodes PE and CE in order to cause the injection of holes from the pixel electrode PE to the hole transport layer HTL It is advantageous to make it smaller compared to the minimum value of the forward bias to be applied between the electrodes PE and CE in order to cause the injection of electrons from the CE into the electron transport layer ETL. Further, when this structure is adopted, the hole density in the layer adjacent to the hole blocking layer HBL among the light emitting layers EML1 to EML3 is increased. Therefore, by adopting this structure, it is possible to more easily suppress the light emitting layer EML1 from emitting light in the pixel PX2, and to suppress the light emitting layers EML1 and EML2 from emitting light in the pixel PX3. In addition, when this structure is adopted, higher luminous efficiency can be realized.

  18 is a cross-sectional view showing another modification of the structure of FIG. The structure of FIG. 18 is the same as the structure of FIG. 6 except that the counter electrode CE is covered with the optical matching layer MC.

  When this structure is adopted, for example, the minimum value of the forward bias to be applied between the electrodes PE and CE in order to cause injection of electrons from the counter electrode CE to the electron transport layer ETL is determined from the pixel electrode PE to the hole. It is smaller than the minimum value of the forward bias to be applied between the electrodes PE and CE to cause the injection of holes into the transport layer HTL. Alternatively, the barrier against electrons at the interface between the electron transport layer ETL and the light emitting layer EML1 is made smaller than the hole barrier at the interface between the hole transport layer HTL and the light emitting layers EML1 to EML3. Alternatively, as a combination of the hole transport layer HTL and the electron transport layer ETL, a hole transport layer having a smaller hole mobility than that of the electron transport layer ETL is used. Alternatively, the hole mobility of the light emitting layer EML2 is made smaller than its electron mobility, and the hole mobility of the light emitting layer EML3 is made smaller than its electron mobility. Alternatively, two or more of these designs are employed. This can suppress the light emission layer EML1 from emitting light in the pixel PX2, and can suppress the light emission layers EML1 and EML2 from emitting light in the pixel PX3.

  FIG. 19 is a cross-sectional view showing another modification of the structure of FIG. The structure of FIG. 19 is the same as the structure of FIG. 18 except that the stacking order of the light emitting layers EML1 to EML3 is reversed.

  When this structure is adopted, for example, the minimum value of the forward bias to be applied between the electrodes PE and CE to cause the injection of holes from the pixel electrode PE to the hole transport layer HTL is determined from the counter electrode CE. It is smaller than the minimum value of the forward bias to be applied between the electrodes PE and CE in order to cause the injection of electrons into the electron transport layer ETL. Alternatively, the barrier against holes at the interface between the hole transport layer HTL and the light emitting layer EML1 is made smaller than the electron barrier at the interface between the electron transport layer ETL and the light emitting layers EML1 to EML3. Alternatively, as a combination of the hole transport layer HTL and the electron transport layer ETL, one having an electron mobility of the electron transport layer ETL smaller than that of the hole transport layer HTL is used. Alternatively, the hole mobility of the light emitting layer EML1 is made larger than its electron mobility, and the hole mobility of the light emitting layer EML2 is made larger than its electron mobility. Alternatively, two or more of these designs are employed. This can suppress the light emission layer EML1 from emitting light in the pixel PX2, and can suppress the light emission layers EML1 and EML2 from emitting light in the pixel PX3.

  When the organic EL element OLED has the structure shown in FIGS. 6 and 8 to 19, an arrangement different from that shown in FIG. 7 can be adopted for the light emitting layer.

FIG. 20 is a plan view schematically showing another example of the arrangement of the light emitting layers.
In this arrangement, the light emitting part EA3 is a right-angled quadrilateral. The light emitting layer EML3 is a right quadrilateral corresponding to the right quadrilateral region occupied by the light emitting portion EA3. The light emitting layer EML3 is arranged in the X direction and the Y direction corresponding to the triplets formed by the pixels PX1 to PX3.

  The light emitting part EA2 is bent along the side of the right-angled quadrilateral region occupied by the light emitting part EA3. The light emitting units EA2 and EA3 are arranged in the X direction and in the Y direction. These light emitting portions EA2 and EA3 are arranged in a rectangular region. The light emitting layer EML2 is a right-sided quadrilateral corresponding to the region occupied by the light emitting portions EA2 and EA3. The light emitting layer EML2 is arranged in the X direction and the Y direction corresponding to the triplets formed by the pixels PX1 to PX3.

  The light emitting unit EA1 is bent along the side of the right-angled quadrilateral region occupied by the light emitting units EA2 and EA3. The light emitting units EA1 to EA3 are arranged in the X direction and in the Y direction. These light emitting portions EA1 to EA3 are arranged in a rectangular region. The light emitting layer EML1 is a continuous film extending over the display area.

  In the arrangement of FIG. 20, the light emitting unit EA2 has a larger area than the light emitting unit EA1, and the light emitting unit EA1 has a larger area than the light emitting units EA2 and EA3. Therefore, when the arrangement of FIG. 20 is adopted, when the luminance degradation due to energization at a constant aperture ratio of the light emitting unit EA2 is larger than that of the light emitting unit EA3, the organic EL element OLED is interposed between the pixels PX2 and PX3. The lifespan of can be made almost equal. In addition, when the luminance degradation due to energization at a constant aperture ratio of the light emitting unit EA1 is larger than that of the light emitting units EA2 and EA3, the lifetime of the organic EL element OLED is substantially reduced between the pixel PX1 and the pixels PX2 to PX3. Can be equal.

Thereby, the luminance deterioration due to the energization of the organic EL element OLED can be made almost equal between the pixels PX1 to PX3, the white color shift due to the difference in luminance deterioration of each color is eliminated, and the product life can be greatly improved. .

  By the way, when the arrangement of FIG. 7 is adopted, in order to make the area of the light emitting unit EA1 larger than the areas of the light emitting units EA2 and EA3, the size of the light emitting unit EA1 in the X direction is usually increased. The dimension in the X direction of EA2 and EA3 is reduced. When the dimensions of the light emitting portions EA2 and EA3 in the X direction are reduced, it is necessary to correspondingly reduce the dimensions of the light emitting layers EML2 and EML3 in the X direction. That is, it is necessary to further reduce the width of the slit provided in the vapor deposition mask used to form the light emitting layers EML2 and EML3. However, it is difficult to form a narrow slit, and therefore a mask provided with such a slit is expensive.

On the other hand, when the arrangement of FIG. 20 is adopted, the dimensions L _x 1 and L _y 1 of the light emitting part EA1, the dimensions L _x 2 and L _y 2 of the light emitting part EA2, and the dimension L _x 3 of the light emitting part EA3 and Even if L _y 3 is the same, the area of the light emitting part EA1 can be larger than that of the light emitting part EA2, and the area of the light emitting part EA2 can be larger than that of the light emitting part EA3. That is, when the arrangement of FIG. 20 is adopted, the dimensions in the X direction of the light emitting layers EML3 and EML2 are made larger than those in the case of adopting the arrangement of FIG. 7 by increasing the dimensions L _y 1 and L _y 2 in the Y direction. can do. That is, when the arrangement of FIG. 20 is adopted, the area of the light emitting part EA1 is compared with the light emitting part EA2 by using a vapor deposition mask that is easy to manufacture without reducing the width of the slit provided in the vapor deposition mask. The area of the light emitting part EA1 can be made larger than the area of the light emitting part EA3.

Various modifications can be made to the arrangement of FIG.
FIG. 21 is a plan view schematically showing another example of the arrangement of the light emitting layers.

  In this arrangement, the light emitting part EA3 is a right-angled quadrilateral. The light emitting layer EML3 is a right quadrilateral corresponding to the right quadrilateral region occupied by the light emitting portion EA3. The light emitting layer EML3 is arranged in the X direction and the Y direction corresponding to the triplets formed by the pixels PX1 to PX3.

  The light emitting unit EA2 surrounds the light emitting unit EA3. Specifically, the light emitting unit EA2 is bent along the four sides of the right-angled quadrangular region occupied by the light emitting unit EA3. The light emitting units EA2 are arranged in the X direction and in the Y direction. The light emitting unit EA2 is arranged in a right quadrilateral region. The light emitting layer EML2 is a right-sided quadrilateral corresponding to the region occupied by the light emitting portions EA2 and EA3. The light emitting layer EML2 is arranged in the X direction and the Y direction corresponding to the triplets formed by the pixels PX1 to PX3.

  The light emitting unit EA1 surrounds the light emitting unit EA2. Specifically, the light emitting unit EA1 is bent along the four sides of the right quadrilateral region occupied by the light emitting units EA2 and EA3. The light emitting units EA1 are arranged in the X direction and in the Y direction. The light emitting unit EA1 is arranged in a rectangular quadrangular region. The light emitting layer EML1 is a continuous film extending over the display area.

  Even when the arrangement of FIG. 21 is adopted, the same effect as described with reference to FIG. 20 can be obtained.

  The area of the light emitting units EA1 to EA3 may not satisfy the relationship described with reference to FIGS. For example, as shown in FIGS. 4 and 7, the areas of the light emitting units EA1 to EA3 may be equal to each other.

When the organic EL element OLED is provided with a function as an optical resonator, the optical path length between the reflecting surfaces of the optical resonator is, for example, zero-order interference mode: first peak mode (normal line when the optical path length is increased from zero) The intensity of the light traveling in the direction is set to an integer multiple of the optical path length at which the maximum value is first shown. For example, when the emission colors of the pixels PX1 to PX3 are blue, green, and red, respectively, the previous optical path length is set to an integer multiple of 66 nm to 87 nm in the pixel PX1, and the previous optical path length is set to 87 nm in the pixel PX2. It is larger and is an integer multiple of less than 113 nm. In the pixel PX3, the previous optical path length is an integral multiple within the range of 113 nm to 160 nm.

In addition, the organic layer ORG can be made thin by setting the optical path length as short as possible, that is, setting the interference mode to a lower order, ideally the 0th order interference mode. The amount of material to be reduced can be reduced. In addition, in this case, the resonance condition can be easily optimized in each of the pixels PX1 to PX3. In addition, the voltage for driving the organic EL element OLED can be lowered, and the power consumption can be further reduced.

  The previous optical path length is changed by changing the refractive index and thickness of the layer interposed between the reflecting surfaces of the optical resonator. However, in many cases, the refractive index of these layers cannot be changed freely. For example, the refractive index of the material used for the organic layer ORG and the pixel electrode PE is normally 1.5 to 3.0. Therefore, normally, the previous optical path length is adjusted by the thickness of the layer interposed between the reflecting surfaces of the optical resonator. Note that the refractive index of the material also considers wavelength dispersion.

  Typically, the blue light emitting layer, the green light emitting layer, and the red light emitting layer are formed in this order, or are formed in the reverse order. In this case, it is easy to prevent the purity of the light emission color from decreasing in the pixels PX2 and PX3.

  In this embodiment, the present invention is applied to a top emission type organic EL display device, but the present invention is also applicable to a bottom emission type organic EL display device. However, the effect obtained by adopting the optical resonator structure is greater in the top emission type organic EL display device than in the bottom emission type organic EL display device.

  In this aspect, a configuration in which a current signal is written as a video signal in the pixel circuit is adopted, but a configuration in which a voltage signal is written as a video signal in the pixel circuit can also be employed. In this embodiment, a p-channel thin film transistor is used, but an n-channel thin film transistor may be used.

Examples of the present invention will be described below.
Example 1
The organic EL display device shown in FIGS. 1 and 2 was manufactured by the method described below. In this example, the structure shown in FIG. 5 is adopted for the organic EL elements OLED of the pixels PX1 to PX3. In this example, the structure shown in FIG. 4 is adopted for the light emitting layers EML1 to EML3. In this example, the film thickness is set to twice the 0th-order interference mode, that is, the first-order interference mode.

First, the array substrate described above was prepared. Here, a glass substrate was used as the substrate SUB. As the reflective layer REF and the pixel electrode PE, an aluminum layer having a thickness of 130 nm and an ITO layer having a thickness of 50 nm were used, respectively. The opening width in the X direction of the partition insulating layer PI was 22.5 μm.

  Next, an amorphous carbon layer having a thickness of 10 nm was formed as the hole injection layer HIL on the pixel electrode PE and the partition insulating layer PI. The hole injection layer HIL was a continuous film extending over the display region.

  Next, N, N′-diphenyl-N, N′-bis (1-naphthylphenyl) -1,1′-biphenyl-4,4′-diamine is formed on the hole injection layer HIL as a hole transport layer HTL. A layer made of (α-NPD) having a thickness of 30 nm was formed by a vacuum deposition method. The hole transport layer HTL was a continuous film extending over the display region.

Then, on the hole transport layer HTL, at a position corresponding to the pixel electrode PE of the pixel PX3, tris (8-hydroxyquinolate) aluminum (Alq ₃ ) is included as a host material, and 2- (1, 1-dimethylethyl) -6 (2- (2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H, 5H-benzo (ij) quinolizin-9-yl) ethenyl) -4H A red light emitting layer EML3 having a thickness of 80 nm containing -pyran-4-ylidene) propanedinitrile (DCJTB) was formed. The light emitting layer EML3 was formed by a vacuum deposition method using a fine mask provided with openings corresponding to the columns of the pixels PX3. The position of the light emitting layer EML3 was exactly matched to the target position on the substrate SUB.

Next, on the hole transport layer HTL, at a position corresponding to the pixel electrode PE of the pixel PX3, a green light emitting layer EML2 having a thickness of 30 nm containing Alq ₃ as a host material and Coumarin 6 as a dopant is formed. did. The light emitting layer EML2 was formed by a vacuum vapor deposition method using a fine mask provided with openings corresponding to the columns formed by pairs of adjacent pixels PX2 and PX3. The position of the light emitting layer EML2 was exactly matched to the target position on the substrate SUB.

  Subsequently, 4,4′-bis (2,2′-diphenyl-ethen-1-yl) -diphenyl (BPVBI) is contained as a host material on the light emitting layers EML2 and EML3 and the hole transport layer HTL, and a dopant As a result, a blue light emitting layer EML1 having a thickness of 30 nm containing perylene was formed. The light emitting layer EML1 was formed by a vacuum evaporation method using a rough mask in which an opening corresponding to the display region was formed.

Thereafter, an Alq ₃ layer having a thickness of 30 nm was formed as an electron transport layer ETL on the light-emitting layer EML1 by a vacuum deposition method. The electron transport layer ETL was a continuous film extending over the display area.

  Next, a 1-nm-thick lithium fluoride layer was formed on the electron transport layer ETL as the electron injection layer EIL. The electron injection layer EIL was a continuous film extending over the display area.

  Subsequently, an MgAg layer having a thickness of 20 nm was formed as a light transmissive counter electrode CE on the electron injection layer EIL. The ratio of magnesium to silver was set to contain 60 to 98% of silver in order to have high light transmittance. The counter electrode CE was a continuous film extending over the display area.

  Thereafter, the organic EL element OLED was sealed, and the video signal line driver XDR and the scanning signal line driver YDR were mounted on the display panel DP. As described above, the organic EL display device shown in FIGS. 1 and 2 was obtained. This organic EL display device is referred to as Sample 1.

The sample 1 is driven so that the reference white (C) of (u ′, v ′) = (0.20, 0.46) is displayed at a luminance of 100 cd / m ² when the screen is observed from the front. did.

  Next, in this state, the pixels PX1 to PX3 were sequentially turned on, and the luminance and chromaticity (u ′, v ′) were measured for each emission color. As a result, the organic EL element OLED of the pixel PX1 was 3 cd / A, (0.14, 0.23). Further, the organic EL element OLED of the pixel PX2 was 10 cd / A, (0.08, 0.55). And about organic EL element OLED of pixel PX3, red was 2 cd / A, (0.39, 0.54).

  Next, in this state, the screen was observed from a direction of 60 ° with respect to the normal line of the screen, and the color deviation Δu′v ′ from the reference white (C) of the display color was measured. As a result, the color shift Δu′v ′ was 0.050. The color shift Δu′v ′ is a half power of the sum of the square of the displacement Δu ′ of the chromaticity coordinate u ′ and the square of the displacement Δv ′ of the chromaticity coordinate v ′.

(Comparative Example 1)
FIG. 22 is a cross-sectional view schematically showing the structure of the organic EL element included in the organic EL display device according to Comparative Example 1.

  In this example, the organic EL display device of FIGS. 1 and 2 was manufactured by the same method as described for the sample 1 except that the structure of FIG. 22 was adopted for the light emitting layers EML1 to EML3. Specifically, in this example, the light emitting layer EML3 is formed on the hole transport layer HTL and at a position corresponding to the pixel electrode PE of the pixel PX3. The light emitting layer EML3 was formed by a vacuum deposition method using a fine mask provided with openings corresponding to the columns of the pixels PX3. The position of the light emitting layer EML3 was exactly matched to the target position on the substrate SUB. The thickness of the light emitting layer EML3 was 30 nm. The light emitting layer EML2 was formed on the hole transport layer HTL at a position corresponding to the pixel electrode PE of the pixel PX2. The light emitting layer EML2 was formed by a vacuum evaporation method using a fine mask provided with openings corresponding to the columns of the pixels PX2. The position of the light emitting layer EML2 was exactly matched to the target position on the substrate SUB. The thickness of the light emitting layer EML2 was 30 nm. The light emitting layer EML1 was formed on the hole transport layer HTL at a position corresponding to the pixel electrode PE of the pixel PX1. The light emitting layer EML1 was formed by a vacuum deposition method using a fine mask provided with openings corresponding to the columns of the pixels PX1. The position of the light emitting layer EML1 was exactly matched to the target position on the substrate SUB. The thickness of the light emitting layer EML1 was 30 nm. This organic EL display device is referred to as Sample 2.

The same test as sample 1 was performed on sample 2. Specifically, Sample 2 was driven such that the current consumption was equal to Sample 1 and the reference white color (C) was displayed when the screen was observed from the front. As a result, the luminance when the screen was observed from the front was 8 cd / m ² .

  Next, in this state, the pixels PX1 to PX3 were sequentially turned on, and the luminance and chromaticity (u ′, v ′) were measured for each emission color. As a result, the organic EL element OLED of the pixel PX1 was 3 cd / A, (0.14, 0.23). Further, the organic EL element OLED of the pixel PX2 was 5 cd / A, (0.13, 0.55). And about the organic EL element OLED of pixel PX3, red was 0.1 cd / A, (0.33, 0.54).

  In this state, the screen was observed from the direction of 60 ° with respect to the normal line of the screen, and the color shift Δu′v ′ from the reference white (C) of the display color was measured. As a result, the color shift Δu′v ′ was 0.200.

(Example 2)
The organic EL display device shown in FIGS. 1 and 2 was manufactured by the method described below. In this example, the structure shown in FIG. 6 is adopted for the organic EL elements OLED of the pixels PX1 to PX3. In this example, the structure shown in FIG. 7 is adopted for the light emitting layers EML1 to EML3. In this example, the film thickness is set in the zero-order interference mode.

First, the array substrate described above was prepared. Here, a glass substrate was used as the substrate SUB. As the reflective layer REF and the pixel electrode PE, an aluminum layer having a thickness of 130 nm and an ITO layer having a thickness of 12.5 nm were used, respectively. The opening width in the X direction of the partition insulating layer PI was 22.5 μm.

  Next, an amorphous carbon layer having a thickness of 3 nm was formed as the hole injection layer HIL on the pixel electrode PE and the partition insulating layer PI. The hole injection layer HIL was a continuous film extending over the display region.

  Next, N, N′-diphenyl-N, N′-bis (1-naphthylphenyl) -1,1′-biphenyl-4,4′-diamine is formed on the hole injection layer HIL as a hole transport layer HTL. A 27.5 nm thick layer made of (α-NPD) was formed by vacuum evaporation. The hole transport layer HTL was a continuous film extending over the display region.

Then, on the hole transport layer HTL, at a position corresponding to the pixel electrode PE of the pixel PX3, tris (8-hydroxyquinolate) aluminum (Alq ₃ ) is included as a host material, and 2- (1, 1-dimethylethyl) -6 (2- (2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H, 5H-benzo (ij) quinolizin-9-yl) ethenyl) -4H A red light emitting layer EML3 having a thickness of 30 nm containing -pyran-4-ylidene) propanedinitrile (DCJTB) was formed. The light emitting layer EML3 was formed by a vacuum deposition method using a fine mask provided with openings corresponding to the columns of the pixels PX3. The position of the light emitting layer EML3 was exactly matched to the target position on the substrate SUB.

Next, on the hole transport layer HTL, at a position corresponding to the pixel electrode PE of the pixels PX2 and PX3, a green light emitting layer EML2 having a thickness of 30 nm containing Alq ₃ as a host material and Coumarin 6 as a dopant. Formed. The light emitting layer EML2 was formed by a vacuum vapor deposition method using a fine mask provided with openings corresponding to the columns formed by pairs of adjacent pixels PX2 and PX3. The position of the light emitting layer EML2 was exactly matched to the target position on the substrate SUB.

  Subsequently, 4,4′-bis (2,2′-diphenyl-ethen-1-yl) -diphenyl (BPVBI) is contained as a host material on the light emitting layers EML2 and EML3 and the hole transport layer HTL, and a dopant A 20-nm-thick blue light-emitting layer EML1 containing perylene was formed. The light emitting layer EML1 was formed by a vacuum evaporation method using a rough mask in which an opening corresponding to the display region was formed.

Thereafter, an Alq ₃ layer having a thickness of 15 nm was formed as an electron transport layer ETL on the light-emitting layer EML1 by a vacuum deposition method. The electron transport layer ETL was a continuous film extending over the display area.

  Next, a 1-nm-thick lithium fluoride layer was formed on the electron transport layer ETL as the electron injection layer EIL. The electron injection layer EIL was a continuous film extending over the display area.

  Subsequently, an MgAg layer having a thickness of 20 nm was formed as a light transmissive counter electrode CE on the electron injection layer EIL. The ratio of magnesium to silver was set to contain 60 to 98% of silver in order to have high light transmittance. The counter electrode CE was a continuous film extending over the display area.

  Thereafter, the organic EL element OLED was sealed, and the video signal line driver XDR and the scanning signal line driver YDR were mounted on the display panel DP. As described above, the organic EL display device shown in FIGS. 1 and 2 was obtained. This organic EL display device is referred to as Sample 3.

The same test as sample 1 was performed on sample 3. Specifically, the sample 3 was driven so that the current consumption was equal to that of the sample 1 and the reference white color (C) was displayed when the screen was observed from the front. As a result, the luminance when the screen was observed from the front was 300 cd / m ² .

  Next, in this state, the pixels PX1 to PX3 were sequentially turned on, and the luminance and chromaticity (u ′, v ′) were measured for each emission color. As a result, the organic EL element OLED of the pixel PX1 was 4 cd / A, (0.14, 0.23). The organic EL element OLED of the pixel PX2 was 20 cd / A, (0.07, 0.57). And about the organic EL element OLED of pixel PX3, red was 10 cd / A, (0.44, 0.53).

  In this state, the screen was observed from the direction of 60 ° with respect to the normal line of the screen, and the color shift Δu′v ′ from the reference white (C) of the display color was measured. As a result, the color shift Δu′v ′ was 0.015.

In addition, the voltage of the organic EL element OLED decreased, and the power consumption was 0.8 times that of Sample 1.
In addition, the amount of material used for the organic layer ORG was 0.5 times that of Sample 1.

(Example 3)
The organic EL display device shown in FIGS. 1 and 2 was manufactured by the method described below. In this example, the structure shown in FIG. 10 is adopted for the organic EL elements OLED of the pixels PX1 to PX3. In this example, the structure shown in FIG. 7 is adopted for the light emitting layers EML1 to EML3. In this example, the film thickness was set twice as much as the 0th order interference mode, that is, in the 1st order interference mode.

  First, the array substrate described above was prepared. Here, a glass substrate was used as the substrate SUB. As the reflective layer REF and the pixel electrode PE, an aluminum layer having a thickness of 100 nm and an ITO layer having a thickness of 85 nm were used, respectively. The opening width in the X direction of the partition insulating layer PI was 22.5 μm.

Next, Alq ₃ is included as a host material at a position corresponding to the pixel electrode PE of the pixel PX3, and 4- (dicyanomethylene) -2-methyl-6- (julolidin-4-yl-vinyl) -4H— is used as a dopant. A red light emitting layer EML3 containing pyran (DCM2) and having a thickness of 50 nm was formed. The light emitting layer EML3 was formed by a vacuum deposition method using a fine mask provided with openings corresponding to the columns of the pixels PX3. The position of the light emitting layer EML3 was exactly matched to the target position on the substrate SUB.

Next, a green light emitting layer EML2 having a thickness of 30 nm containing Alq ₃ as a host material and Coumarin 6 as a dopant was formed at a position corresponding to the pixel electrode PE of the pixels PX2 and PX3. The light emitting layer EML2 was formed by a vacuum vapor deposition method using a fine mask provided with openings corresponding to the columns formed by pairs of adjacent pixels PX2 and PX3. The position of the light emitting layer EML2 was exactly matched to the target position on the substrate SUB.

  Subsequently, bis (2-methyl-8-quinolinolato) (para-phenyl-phenolato) aluminum (BAlq) is included as a host material on the light emitting layers EML2 and EML3 and the pixel electrode PE of the pixel PX1, and 4 as a dopant. , 4′-bis ((2-carbazole) vinylene) biphenyl) (BczVBi) was formed to form a 65 nm-thick blue light-emitting layer EML1. The light emitting layer EML1 was formed by a vacuum evaporation method using a rough mask in which an opening corresponding to the display region was formed.

In each of the light emitting layers EML1 to EML3, the concentration of the dopant material was set to 20% or less. Further, Alq ₃ and BAlq used as host materials are materials having electron mobility larger than hole mobility.

  Next, an MgAg layer having a thickness of 20 nm was formed on the light emitting layer EML1 as the light transmissive counter electrode CE. The counter electrode CE was a continuous film extending over the display area. In order to realize high light transmittance, the concentration of silver in the counter electrode CE was set to 60 to 98 atomic%.

  Next, an optical matching layer MC made of SiON and having a thickness of 140 nm was formed on the counter electrode CE. Thereafter, the organic EL element OLED was sealed, and the video signal line driver XDR and the scanning signal line driver YDR were mounted on the display panel DP. Further, a circularly polarizing plate (not shown) was attached to the display surface. As described above, the organic EL display device shown in FIGS. 1 and 2 was obtained. Hereinafter, this organic EL display device is referred to as Sample 4.

The same test as sample 1 was performed on sample 4. Specifically, Sample 4 was driven such that the current consumption was equal to Sample 1 and the reference white (C) was displayed when the screen was observed from the front. As a result, the luminance when the screen was observed from the front was 150 cd / m ² .

  Next, in this state, the pixels PX1 to PX3 were sequentially turned on, and the luminance and chromaticity (u ′, v ′) were measured for each emission color. As a result, the organic EL element OLED of the pixel PX1 was 4.5 cd / A, (0.14, 0.23). The organic EL element OLED of the pixel PX2 was 15 cd / A, (0.08, 0.55). For the organic EL element OLED of the pixel PX3, the red color was 3 cd / A, (0.39, 0.54).

  Next, in this state, the screen was observed from a direction of 60 ° with respect to the normal line of the screen, and the color deviation Δu′v ′ from the reference white (C) of the display color was measured. As a result, the color shift Δu′v ′ was 0.030.

Example 4
The organic EL display device shown in FIGS. 1 and 2 was manufactured by the method described below. In this example, the structure shown in FIG. 12 is adopted for the organic EL elements OLED of the pixels PX1 to PX3. In this example, the structure shown in FIG. 7 is adopted for the light emitting layers EML1 to EML3. In this example, the film thickness was set twice as much as the 0th order interference mode, that is, in the 1st order interference mode.

First, an array substrate similar to that used in Sample 4 was prepared.
Next, a 30 nm-thick hole transport layer HTL made of α-NPD was formed on the pixel electrode PE and the partition insulating layer PI by vacuum deposition. The hole transport layer HTL was formed by a vacuum evaporation method using a rough mask in which an opening corresponding to the display region was formed. Note that the hole mobility of α-NPD is 5 × 10 ⁻⁴ cm ² / V · s.

  Next, the light emitting layers EML3 and EML2 were sequentially formed by the same method as described for the sample 4. Subsequently, the light emitting layer EML1 was formed by the same method as described for the sample 4 except that the thickness was set to 20 nm.

  Next, an electron transport layer ETL having a thickness of 15 nm made of 2,5-di (aryl) silole derivative (PSP) having 3-methylphenyl was formed on the light-emitting layer EML1. The electron transport layer ETL was formed by a vacuum evaporation method using a rough mask in which an opening corresponding to the display region was formed. Note that the electron mobility of PSP is much higher than the hole mobility of α-NPD.

  Next, the counter electrode CE and the optical matching layer MC were sequentially formed on the electron transport layer ETL by the same method as described for the sample 4.

  Thereafter, the organic EL element OLED was sealed by the same method as described for the sample 4, and the video signal line driver XDR and the scanning signal line driver YDR were mounted on the display panel DP. Further, a circularly polarizing plate (not shown) was attached to the display surface. As described above, the organic EL display device shown in FIGS. 1 and 2 was obtained. Hereinafter, this organic EL display device is referred to as Sample 5.

The same test as sample 1 was performed on sample 5. Specifically, Sample 5 was driven such that the current consumption was equal to Sample 1 and the reference white color (C) was displayed when the screen was observed from the front. As a result, the luminance when the screen was observed from the front was 220 cd / m ² .

  Next, in this state, the pixels PX1 to PX3 were sequentially turned on, and the luminance and chromaticity (u ′, v ′) were measured for each emission color. As a result, the organic EL element OLED of the pixel PX1 was 4.5 cd / A, (0.14, 0.23). In addition, the organic EL element OLED of the pixel PX2 was 18 cd / A, (0.07, 0.56). And about the organic EL element OLED of pixel PX3, red was 5 cd / A, (0.42, 0.54).

  Next, in this state, the screen was observed from a direction of 60 ° with respect to the normal line of the screen, and the color deviation Δu′v ′ from the reference white (C) of the display color was measured. As a result, the color shift Δu′v ′ was 0.030.

(Example 5)
In this example, the organic EL display device shown in FIGS. 1 and 2 is manufactured by the same method as described for the sample 5 except that the structure shown in FIG. 14 is adopted for the organic EL elements OLED of the pixels PX1 to PX3. did. Specifically, prior to the formation of the counter electrode CE, an electron injection layer EIL having a thickness of 1 nm made of lithium fluoride was formed on the electron transport layer ETL by vacuum evaporation. The electron injection layer EIL was formed by a vacuum evaporation method using a rough mask in which an opening corresponding to the display region was formed. Hereinafter, the organic EL display device thus obtained is referred to as Sample 6.

The same test as sample 1 was performed on sample 6. Specifically, Sample 6 was driven such that the current consumption was equal to Sample 1 and the reference white (C) was displayed when the screen was observed from the front. As a result, the luminance when the screen was observed from the front was 300 cd / m ² .

  Next, in this state, the pixels PX1 to PX3 were sequentially turned on, and the luminance and chromaticity (u ′, v ′) were measured for each emission color. As a result, the organic EL element OLED of the pixel PX1 was 4.5 cd / A, (0.14, 0.23). The organic EL element OLED of the pixel PX2 was 22 cd / A, (0.07, 0.57). And about the organic EL element OLED of pixel PX3, red was 8 cd / A, (0.46, 0.53).

  Next, in this state, the screen was observed from a direction of 60 ° with respect to the normal line of the screen, and the color deviation Δu′v ′ from the reference white (C) of the display color was measured. As a result, the color shift Δu′v ′ was 0.030.

(Example 6)
In this example, the organic EL display device shown in FIGS. 1 and 2 is manufactured by the same method as described for the sample 6 except that the structure shown in FIG. 15 is adopted for the organic EL elements OLED of the pixels PX1 to PX3. did. Specifically, prior to forming the light emitting layer EML3, an electron blocking layer EBL having a thickness of 5 nm was formed on the hole transport layer HTL by a vacuum deposition method. The electron blocking layer EBL was formed by a vacuum evaporation method using a rough mask in which an opening corresponding to the display region was formed. Hereinafter, the organic EL display device thus obtained is referred to as Sample 7.

The same test as sample 1 was performed on sample 7. Specifically, the sample 7 was driven so that the current consumption was equal to that of the sample 1 and the reference white color (C) was displayed when the screen was observed from the front. As a result, the luminance when the screen was observed from the front was 340 cd / m ² .

  Next, in this state, the pixels PX1 to PX3 were sequentially turned on, and the luminance and chromaticity (u ′, v ′) were measured for each emission color. As a result, the organic EL element OLED of the pixel PX1 was 5 cd / A, (0.14, 0.23). The organic EL element OLED of the pixel PX2 was 24 cd / A, (0.07, 0.57). And about organic EL element OLED of pixel PX3, red was 9 cd / A, (0.48, 0.53).

  Next, in this state, the screen was observed from a direction of 60 ° with respect to the normal line of the screen, and the color deviation Δu′v ′ from the reference white (C) of the display color was measured. As a result, the color shift Δu′v ′ was 0.030.

(Example 7)
The organic EL display device shown in FIGS. 1 and 2 was manufactured by the method described below. In this example, the structure shown in FIG. 11 is adopted for the organic EL elements OLED of the pixels PX1 to PX3. In this example, the structure shown in FIG. 7 is adopted for the light emitting layers EML1 to EML3.

First, an array substrate similar to that used in Sample 4 was prepared.
Next, a 65-nm-thick blue light-emitting layer EML1 containing α-NPD as a host material and BczVBi as a dopant was formed at positions corresponding to the pixel electrodes PE of the pixels PX1 to PX3. The light emitting layer EML1 was formed by a vacuum evaporation method using a rough mask in which an opening corresponding to the display region was formed.

  Next, a green light emitting layer EML2 having a thickness of 30 nm containing α-NPD as a host material and Coumarin 6 as a dopant was formed on the light emitting layer EML1 at a position corresponding to the pixel electrodes PE of the pixels PX2 and PX3. . The light emitting layer EML2 was formed by a vacuum vapor deposition method using a fine mask provided with openings corresponding to the columns formed by pairs of adjacent pixels PX2 and PX3. The position of the light emitting layer EML2 was exactly matched to the target position on the substrate SUB.

  Subsequently, a 50 nm thick light emitting layer EML3 containing α-NPD as a host material and DCM2 as a dopant was formed on the light emitting layer EML1 at a position corresponding to the pixel electrode PE of the pixel PX3. The light emitting layer EML3 was formed by a vacuum deposition method using a fine mask provided with openings corresponding to the columns formed by the pixels PX3. The position of the light emitting layer EML3 was exactly matched to the target position on the substrate SUB.

  Note that α-NPD used as a host material is a material having a hole mobility larger than an electron mobility.

  Next, the counter electrode CE and the optical matching layer MC were sequentially formed on the electron transport layer ETL by the same method as described for the sample 4.

  Thereafter, the organic EL element OLED was sealed by the same method as described for the sample 4, and the video signal line driver XDR and the scanning signal line driver YDR were mounted on the display panel DP. Further, a circularly polarizing plate (not shown) was attached to the display surface. As described above, the organic EL display device shown in FIGS. 1 and 2 was obtained. Hereinafter, this organic EL display device is referred to as Sample 8.

The same test as Sample 1 was also performed on Sample 8. Specifically, the sample 8 was driven so that the current consumption was equal to that of the sample 1 and the reference white color (C) was displayed when the screen was observed from the front. As a result, the luminance when the screen was observed from the front was 150 cd / m ² .

  Next, in this state, the pixels PX1 to PX3 were sequentially turned on, and the luminance and chromaticity (u ′, v ′) were measured for each emission color. As a result, the organic EL element OLED of the pixel PX1 was 4.5 cd / A, (0.14, 0.23). The organic EL element OLED of the pixel PX2 was 15 cd / A, (0.08, 0.55). For the organic EL element OLED of the pixel PX3, the red color was 3 cd / A, (0.39, 0.54).

  Next, in this state, the screen was observed from a direction of 60 ° with respect to the normal line of the screen, and the color deviation Δu′v ′ from the reference white (C) of the display color was measured. As a result, the color shift Δu′v ′ was 0.030.

(Example 8)
The organic EL display device shown in FIGS. 1 and 2 was manufactured by the method described below. In this example, the structure shown in FIG. 13 is adopted for the organic EL elements OLED of the pixels PX1 to PX3. In this example, the structure shown in FIG. 7 is adopted for the light emitting layers EML1 to EML3.

First, an array substrate similar to that used in Sample 8 was prepared.
Next, a 30 nm-thick hole transport layer HTL made of α-NPD was formed on the pixel electrode PE and the partition insulating layer PI by vacuum deposition. The hole transport layer HTL was formed by a vacuum evaporation method using a rough mask in which an opening corresponding to the display region was formed.

  Subsequently, the light emitting layers EML1 to EML3 were sequentially formed by the same method as described for the sample 8.

Next, an electron transport layer ETL made of Alq ₃ and having a thickness of 15 nm was formed on the light emitting layer EML3. The electron transport layer ETL was formed by a vacuum evaporation method using a rough mask in which an opening corresponding to the display region was formed. Note that Alq ₃ has a lower electron mobility than that of α-NPD.

  Next, the counter electrode CE and the optical matching layer MC were sequentially formed on the electron transport layer ETL by the same method as described for the sample 4.

  Thereafter, the organic EL element OLED was sealed by the same method as described for the sample 4, and the video signal line driver XDR and the scanning signal line driver YDR were mounted on the display panel DP. Further, a circularly polarizing plate (not shown) was attached to the display surface. As described above, the organic EL display device shown in FIGS. 1 and 2 was obtained. Hereinafter, this organic EL display device is referred to as Sample 9.

A test similar to that of Sample 1 was also performed on Sample 9. Specifically, the sample 9 was driven so that the current consumption was equal to that of the sample 1 and the reference white color (C) was displayed when the screen was observed from the front. As a result, the luminance when the screen was observed from the front was 220 cd / m ² .

  Next, in this state, the pixels PX1 to PX3 were sequentially turned on, and the luminance and chromaticity (u ′, v ′) were measured for each emission color. As a result, the organic EL element OLED of the pixel PX1 was 4.5 cd / A, (0.14, 0.23). In addition, the organic EL element OLED of the pixel PX2 was 18 cd / A, (0.07, 0.56). And about the organic EL element OLED of pixel PX3, red was 5 cd / A, (0.42, 0.54).

  Next, in this state, the screen was observed from a direction of 60 ° with respect to the normal line of the screen, and the color deviation Δu′v ′ from the reference white (C) of the display color was measured. As a result, the color shift Δu′v ′ was 0.030.

Example 9
In this example, the organic EL display device shown in FIGS. 1 and 2 is manufactured by the same method as described for the sample 9 except that the structure shown in FIG. 16 is adopted for the organic EL elements OLED of the pixels PX1 to PX3. did. Specifically, prior to forming the hole transport layer HTL, a 5 nm thick hole injection layer HIL made of amorphous carbon was formed on the pixel electrode PE by vacuum deposition. The hole injection layer HIL was formed by a vacuum evaporation method using a rough mask in which an opening corresponding to the display region was formed. Hereinafter, the organic EL display device thus obtained is referred to as Sample 10.

The same test as sample 1 was performed on sample 10. Specifically, the sample 10 was driven so that the current consumption was equal to that of the sample 1 and the reference white color (C) was displayed when the screen was observed from the front. As a result, the luminance when the screen was observed from the front was 300 cd / m ² .

  Next, in this state, the pixels PX1 to PX3 were sequentially turned on, and the luminance and chromaticity (u ′, v ′) were measured for each emission color. As a result, the organic EL element OLED of the pixel PX1 was 4.5 cd / A, (0.14, 0.23). The organic EL element OLED of the pixel PX2 was 22 cd / A, (0.07, 0.57). And about the organic EL element OLED of pixel PX3, red was 8 cd / A, (0.46, 0.53).

  Next, in this state, the screen was observed from a direction of 60 ° with respect to the normal line of the screen, and the color deviation Δu′v ′ from the reference white (C) of the display color was measured. As a result, the color shift Δu′v ′ was 0.030.

(Example 10)
In this example, the organic EL display device shown in FIGS. 1 and 2 is manufactured by the same method as that described for the sample 10 except that the structure shown in FIG. 17 is adopted for the organic EL elements OLED of the pixels PX1 to PX3. did. Specifically, prior to forming the electron transport layer ETL, a 5 nm thick hole blocking layer HBL made of BAlq was formed on the light emitting layers EML1 to EML3 by vacuum deposition. The hole blocking layer HBL was formed by a vacuum evaporation method using a rough mask in which an opening corresponding to the display region was formed. Hereinafter, the organic EL display device thus obtained is referred to as Sample 11.

The same test as sample 1 was performed on sample 7. Specifically, the sample 7 was driven so that the current consumption was equal to that of the sample 1 and the reference white color (C) was displayed when the screen was observed from the front. As a result, the luminance when the screen was observed from the front was 340 cd / m ² .

  Next, in this state, the pixels PX1 to PX3 were sequentially turned on, and the luminance and chromaticity (u ′, v ′) were measured for each emission color. As a result, the organic EL element OLED of the pixel PX1 was 5 cd / A, (0.14, 0.23). The organic EL element OLED of the pixel PX2 was 24 cd / A, (0.07, 0.57). And about organic EL element OLED of pixel PX3, red was 9 cd / A, (0.48, 0.53).

  Next, in this state, the screen was observed from a direction of 60 ° with respect to the normal line of the screen, and the color deviation Δu′v ′ from the reference white (C) of the display color was measured. As a result, the color shift Δu′v ′ was 0.030.

(Example 11)
In this example, the organic EL display device shown in FIGS. 1 and 2 is manufactured by the same method as that described for Sample 6 except that the structure shown in FIG. 18 is adopted for the organic EL elements OLED of the pixels PX1 to PX3. did. Specifically, prior to forming the hole transport layer HTL, a 5 nm thick hole injection layer HIL made of amorphous carbon was formed on the pixel electrode PE by vacuum deposition. The hole injection layer HIL was formed by a vacuum evaporation method using a rough mask in which an opening corresponding to the display region was formed. Hereinafter, the organic EL display device thus obtained is referred to as Sample 12.

The same test as Sample 1 was also performed on Sample 12. Specifically, the sample 12 was driven so that the current consumption was equal to that of the sample 1 and the reference white color (C) was displayed when the screen was observed from the front. As a result, the luminance when the screen was observed from the front was 340 cd / m ² .

  Next, in this state, the pixels PX1 to PX3 were sequentially turned on, and the luminance and chromaticity (u ′, v ′) were measured for each emission color. As a result, the organic EL element OLED of the pixel PX1 was 5 cd / A, (0.14, 0.23). The organic EL element OLED of the pixel PX2 was 24 cd / A, (0.07, 0.57). And about organic EL element OLED of pixel PX3, red was 9 cd / A, (0.48, 0.53).

  Next, in this state, the screen was observed from a direction of 60 ° with respect to the normal line of the screen, and the color deviation Δu′v ′ from the reference white (C) of the display color was measured. As a result, the color shift Δu′v ′ was 0.030.

(Example 12)
In this example, the organic EL display device shown in FIGS. 1 and 2 is manufactured by the same method as described for the sample 10 except that the structure shown in FIG. 19 is adopted for the organic EL elements OLED of the pixels PX1 to PX3. did. Specifically, prior to the formation of the counter electrode CE, an electron injection layer EIL having a thickness of 1 nm made of lithium fluoride was formed on the electron transport layer ETL by vacuum evaporation. The electron injection layer EIL was formed by a vacuum evaporation method using a rough mask in which an opening corresponding to the display region was formed. Hereinafter, the organic EL display device thus obtained is referred to as Sample 13.

A test similar to that of Sample 1 was also performed on Sample 13. Specifically, Sample 13 was driven such that the current consumption was equal to Sample 1 and the reference white color (C) was displayed when the screen was observed from the front. As a result, the luminance when the screen was observed from the front was 340 cd / m ² .

  Next, in this state, the pixels PX1 to PX3 were sequentially turned on, and the luminance and chromaticity (u ′, v ′) were measured for each emission color. As a result, the organic EL element OLED of the pixel PX1 was 5 cd / A, (0.14, 0.23). The organic EL element OLED of the pixel PX2 was 24 cd / A, (0.07, 0.57). And about organic EL element OLED of pixel PX3, red was 9 cd / A, (0.48, 0.53).

  Next, in this state, the screen was observed from a direction of 60 ° with respect to the normal line of the screen, and the color deviation Δu′v ′ from the reference white (C) of the display color was measured. As a result, the color shift Δu′v ′ was 0.030.

(Example 13)
In this example, the organic EL display device shown in FIGS. 1 and 2 was manufactured by the same method as that described for sample 3 except that the following configuration was adopted. Specifically, an optical matching layer MC made of SiON and having a thickness of 70 nm was formed on the counter electrode CE. Hereinafter, the organic EL display device thus obtained is referred to as Sample 14.

  The same test as sample 1 was performed on sample 14. Specifically, the sample 14 was driven so that the current consumption was equal to that of the sample 1 and the reference white color (C) was displayed when the screen was observed from the front. As a result, the luminance when the screen was observed from the front was 500 cd / m 2.

  Next, in this state, the pixels PX1 to PX3 were sequentially turned on, and the luminance and chromaticity (u ′, v ′) were measured for each emission color. As a result, the organic EL element OLED of the pixel PX1 was 6 cd / A, (0.14, 0.23). The organic EL element OLED of the pixel PX2 was 30 cd / A, (0.08, 0.58). And about organic EL element OLED of pixel PX3, red was 15 cd / A, (0.48, 0.53).

  Next, in this state, the screen was observed from a direction of 60 ° with respect to the normal line of the screen, and the color deviation Δu′v ′ from the reference white (C) of the display color was measured. As a result, the color shift Δu′v ′ was 0.015.

(Example 14)
In this example, the organic EL display device shown in FIGS. 1 and 2 was manufactured by the same method as described for the sample 13 except that the structure shown in FIG. 20 was adopted instead of the structure shown in FIG.

Specifically, the dimensions L _x 1 and L _y 1 were 22.5 μm and 15 μm, respectively. The dimensions L _x 2 and L _y 2 were 22.5 μm and 15 μm, respectively. The dimensions L _x 3 and L _y 3 were 22.5 μm and 37.5 μm, respectively. Hereinafter, the organic EL display device thus obtained is referred to as Sample 15.

  A test similar to that of Sample 1 was also performed on Sample 15. Specifically, the sample 15 was driven so that the current consumption was equal to that of the sample 1 and the reference white color (C) was displayed when the screen was observed from the front. As a result, the luminance when the screen was observed from the front was 500 cd / m 2.

  Next, in this state, the pixels PX1 to PX3 were sequentially turned on, and the luminance and chromaticity (u ′, v ′) were measured for each emission color. As a result, the organic EL element OLED of the pixel PX1 was 6 cd / A, (0.14, 0.23). The organic EL element OLED of the pixel PX2 was 30 cd / A, (0.08, 0.58). And about organic EL element OLED of pixel PX3, red was 15 cd / A, (0.48, 0.53).

  Next, in this state, the screen was observed from a direction of 60 ° with respect to the normal line of the screen, and the color deviation Δu′v ′ from the reference white (C) of the display color was measured. As a result, the color shift Δu′v ′ was 0.015.

  In addition, the color shift Δu′v ′ from the reference white color (C) due to energization when white light was turned on was measured. As a result, the color shift Δu′v ′ was 0.030 with respect to 0.150 of Sample 13 after 10,000 hours had elapsed.

(Example 15)
In this example, the organic EL display device shown in FIGS. 1 and 2 was manufactured by the same method as described for the sample 13 except that the structure shown in FIG. 21 was adopted instead of the structure shown in FIG. The organic EL display device thus obtained is referred to as Sample 15.

  A test similar to that of Sample 1 was also performed on Sample 15. Specifically, the sample 15 was driven so that the current consumption was equal to that of the sample 1 and the reference white color (C) was displayed when the screen was observed from the front. As a result, the luminance when the screen was observed from the front was 500 cd / m 2.

  Next, in this state, the pixels PX1 to PX3 were sequentially turned on, and the luminance and chromaticity (u ′, v ′) were measured for each emission color. As a result, the organic EL element OLED of the pixel PX1 was 6 cd / A, (0.14, 0.23). The organic EL element OLED of the pixel PX2 was 30 cd / A, (0.08, 0.58). And about organic EL element OLED of pixel PX3, red was 15 cd / A, (0.48, 0.53).

  Next, in this state, the screen was observed from a direction of 60 ° with respect to the normal line of the screen, and the color deviation Δu′v ′ from the reference white (C) of the display color was measured. As a result, the color shift Δu′v ′ was 0.015.

  In addition, the color shift Δu′v ′ from the reference white color (C) due to energization when white light was turned on was measured. As a result, the color shift Δu′v ′ was 0.030 with respect to 0.150 of Sample 13 after 10,000 hours had elapsed.

(Comparative Example 2)
FIG. 23 is a cross-sectional view schematically showing the structure of the organic EL element included in the organic EL display device according to Comparative Example 2.

  In this example, the organic EL display device of FIGS. 1 and 2 was manufactured by the same method as that described for sample 2 except that the structure of FIG. 23 was adopted for the organic EL element OLED. Specifically, in this example, the hole transport layer HTL and the light emitting layers EML1 to EML3 were formed by the following method.

  That is, a first hole transport material layer having a thickness of 110 nm was formed at a position corresponding to the pixel electrode PE of the pixel PX3. The first hole transport material layer was formed by a vacuum evaporation method using a fine mask provided with openings corresponding to the columns of the pixels PX3. Then, a second hole transport material layer having a thickness of 60 nm was formed at a position corresponding to the pixel electrode PE of the pixel PX2. The second hole transport material layer 2 was formed by a vacuum deposition method using a fine mask provided with openings corresponding to the columns of the pixels PX2. Further, a third hole transport material layer having a thickness of 30 nm was formed on the hole injection layer HIL of the pixel PX1.

  The light emitting layer EML3 was formed on the hole transport layer HTL at a position corresponding to the pixel electrode PE of the pixel PX3. The light emitting layer EML3 was formed by a vacuum deposition method using a fine mask provided with openings corresponding to the columns of the pixels PX3. The light emitting layer EML2 was formed on the hole transport layer HTL at a position corresponding to the pixel electrode PE of the pixel PX2. The light emitting layer EML2 was formed by a vacuum evaporation method using a fine mask provided with openings corresponding to the columns of the pixels PX2. The thickness of the light emitting layer EML2 was made equal to the thickness of the light emitting layer EML3. The light emitting layer EML1 was formed on the hole transport layer HTL at a position corresponding to the pixel electrode PE of the pixel PX1. The light emitting layer EML1 was formed by a vacuum deposition method using a fine mask provided with openings corresponding to the columns of the pixels PX1. The thickness of the light emitting layer EML1 was made equal to the thickness of the light emitting layer EML3. Hereinafter, the organic EL display device thus obtained is referred to as Sample 16.

A test similar to that of Sample 1 was also performed on Sample 16. Specifically, the sample 16 was driven so that the current consumption was equal to that of the sample 1 and the reference white color (C) was displayed when the screen was observed from the front. As a result, the brightness when the screen is observed from the front, the brightness and chromaticity (u ′, v ′) for each emission color, and the reference white (C) of the display color from the direction of 60 ° with respect to the normal of the screen The color shift Δu′v ′ from the sample 1 was the same as that of sample 1.
However, the amount of hole transport material used was 10.5 times that of Sample 1.

(Comparative Example 3)
FIG. 24 is a cross-sectional view schematically showing the structure of the organic EL element included in the organic EL display device according to Comparative Example 3.

  In this example, the organic EL display device of FIGS. 1 and 2 was manufactured by the same method as that described for sample 2 except that the structure of FIG. 24 was adopted for the organic EL element OLED. Specifically, in this example, the light emitting layer EML3 is formed on the hole transport layer HTL and at a position corresponding to the pixel electrode PE of the pixel PX3. The light emitting layer EML3 was formed by a vacuum deposition method using a fine mask provided with openings corresponding to the columns of the pixels PX3. The thickness of the light emitting layer EML3 was set to 110 nm. The light emitting layer EML2 was formed on the hole transport layer HTL at a position corresponding to the pixel electrode PE of the pixel PX2. The light emitting layer EML2 was formed by a vacuum evaporation method using a fine mask provided with openings corresponding to the columns of the pixels PX2. The position of the light emitting layer EML2 was exactly matched to the target position on the substrate SUB. The thickness of the light emitting layer EML2 was 60 nm. The light emitting layer EML1 was formed on the hole transport layer HTL at a position corresponding to the pixel electrode PE of the pixel PX1. The light emitting layer EML1 was formed by a vacuum deposition method using a fine mask provided with openings corresponding to the columns of the pixels PX1. The position of the light emitting layer EML1 was exactly matched to the target position on the substrate SUB. The thickness of the light emitting layer EML1 was 30 nm. This organic EL display device is referred to as Sample 17.

A test similar to that of Sample 1 was also performed on Sample 17. Specifically, Sample 17 was driven so that the current consumption was equal to Sample 1 and the reference white (C) was displayed when the screen was observed from the front. As a result, the brightness when the screen is observed from the front, the brightness and chromaticity (u ′, v ′) for each emission color, and the reference white (C) of the display color from the direction of 60 ° with respect to the normal of the screen The color shift Δu′v ′ from the sample 1 was the same as that of sample 1.
However, compared with Sample 1, the material usage of the light emitting layer EML3 was 1.5 times and the material usage of the light emitting layer EML2 was 2 times.

1 is a plan view schematically showing an organic EL display device according to one embodiment of the present invention. FIG. 2 is a cross-sectional view schematically showing an example of a structure that can be employed in the display device of FIG. FIG. 3 is a cross-sectional view schematically showing an example of a structure that can be employed in an organic EL element included in the display device of FIG. 2. The top view which shows roughly an example of arrangement | positioning of the light emitting layer employable with the display apparatus of FIG. Sectional drawing which shows schematically the other example of the structure employable as the organic EL element which the display apparatus of FIG. 2 contains. Sectional drawing which shows schematically the other example of the structure employable as the organic EL element which the display apparatus of FIG. 2 contains. The top view which shows roughly an example of arrangement | positioning of the light emitting layer employable with the display apparatus of FIG. 2, when the structure of FIG. 6 is employ | adopted as an organic EL element. Sectional drawing which shows the modification of the structure of FIG. Sectional drawing which shows the other modification of the structure of FIG. Sectional drawing which shows the other modification of the structure of FIG. Sectional drawing which shows the other modification of the structure of FIG. Sectional drawing which shows the other modification of the structure of FIG. Sectional drawing which shows the other modification of the structure of FIG. Sectional drawing which shows the other modification of the structure of FIG. Sectional drawing which shows the other modification of the structure of FIG. Sectional drawing which shows the other modification of the structure of FIG. Sectional drawing which shows the other modification of the structure of FIG. Sectional drawing which shows the other modification of the structure of FIG. Sectional drawing which shows the other modification of the structure of FIG. The top view which shows schematically the other example of arrangement | positioning of a light emitting layer. The top view which shows schematically the other example of arrangement | positioning of a light emitting layer. Sectional drawing which shows schematically the structure of the organic EL element which the organic EL display apparatus which concerns on the comparative example 1 contains. Sectional drawing which shows schematically the structure of the organic EL element which the organic EL display apparatus concerning the comparative example 2 contains. Sectional drawing which shows schematically the structure of the organic EL element which the organic EL display apparatus concerning the comparative example 3 contains.

Explanation of symbols

  C ... capacitor, CE ... counter electrode, DE ... drain electrode, DL ... video signal line, DP ... display panel, DR ... drive transistor, EA1 ... light emitting part, EA2 ... light emitting part, EA3 ... light emitting part, EIL ... electron injection layer , EML1 ... light emitting layer, EML2 ... light emitting layer, EML3 ... light emitting layer, ETL ... electron transport layer, G ... gate, GI ... gate insulating film, HIL ... hole injection layer, HTL ... hole transport layer, II ... interlayer insulation Film, MC ... matching layer, ND1 ... power supply terminal, ND1 '... constant potential terminal, ND2 ... power supply terminal, OLED ... organic EL element, ORG ... organic substance layer, PE ... pixel electrode, PI ... partition insulating layer, PS ... passivation film , PSL ... power supply line, PX1 ... pixel, PX2 ... pixel, PX3 ... pixel, REF ... reflective layer, SC ... semiconductor layer, SE ... source electrode, SL1 ... scanning signal line, SL2 ... scanning signal Line, SUB ... insulating substrate, SWa ... switching transistor, SWb ... switching transistor, SWc ... switching transistor, XDR ... video signal line driver, YDR ... scanning signal line driver.

Claims (14)

An insulating substrate;
A scanning signal line located above the insulating substrate;
A first video signal line and a second video signal line, each of which is located above the insulating substrate and intersects the scanning signal line;
A first transistor and a second transistor arranged above the insulating substrate so as to correspond to intersections of the scanning signal line and the first and second video signal lines;
First and second pixel electrodes respectively arranged corresponding to the first and second transistors above the insulating substrate;
The scanning signal line, the first and second video signal lines, and the first and second transistors are positioned above the first and second pixel electrodes, and are opened at the first and second pixel electrodes. A portion corresponding to a region between two pixel electrodes includes a partition insulating layer having a tapered cross section perpendicular to the arrangement direction of the first and second pixel electrodes,
A counter electrode formed above the first and second pixel electrodes and the partition insulating layer;
A part is interposed between the first pixel electrode and the counter electrode, and another part is interposed between the second pixel electrode and the counter electrode, and includes the first and second pixel electrodes. A first light-emitting layer extending over a region;
A second light emitting layer provided only in a region corresponding to the second pixel electrode of the first and second pixel electrodes, and overlapping the first light emitting layer between the second pixel electrode and the counter electrode; Comprising
The first pixel electrode, the counter electrode, and the portion sandwiched between them constitute an optical resonator, and the second pixel electrode, the counter electrode, and the portion sandwiched between them constitute an optical resonator. Organic EL display device.   The first and second pixel electrodes are anodes, the counter electrode is a cathode, and the second light emitting layer is interposed between the first light emitting layer and the second pixel electrode. The organic EL display device described.   3. The organic EL display device according to claim 1, wherein a first portion corresponding to the first pixel electrode emits light in blue, and a second portion corresponding to the second pixel electrode emits light in red or green.   The organic EL display device according to claim 1, wherein the first pixel electrode and the second pixel electrode have the same thickness. An insulating substrate;
A scanning signal line located above the insulating substrate;
First to third video signal lines that are located above the insulating substrate and each intersect with the scanning signal lines;
First to third transistors arranged above the insulating substrate so as to correspond to intersections of the scanning signal lines and the first to third video signal lines, respectively.
First to third pixel electrodes respectively arranged corresponding to the first to third transistors above the insulating substrate;
It is located above the scanning signal line, the first to third video signal lines, and the first to third transistors, and is opened at the position of the first to third pixel electrodes. The portion corresponding to the region between the two pixel electrodes has a cross section perpendicular to the arrangement direction of the first and second pixel electrodes, and the portion corresponding to the region between the second and third pixel electrodes. A partition insulating layer having a tapered cross section perpendicular to the arrangement direction of the second and third pixel electrodes;
A counter electrode formed above the first to third pixel electrodes and the partition insulating layer;
A part is interposed between the first pixel electrode and the counter electrode, the other part is interposed between the second pixel electrode and the counter electrode, and another part is interposed between the third pixel and the third pixel. A first light-emitting layer interposed between an electrode and the counter electrode and extending over a region including the first to third pixel electrodes;
The first to third pixel electrodes are provided only in a region corresponding to the second pixel electrode or a region corresponding to the second and third pixel electrodes, and at least between the second pixel electrode and the counter electrode. And a second light emitting layer overlapping the first light emitting layer,
A third light emitting layer which is provided only in a region corresponding to the third pixel electrode among the first to third pixel electrodes and overlaps the first light emitting layer between the third pixel electrode and the counter electrode; Comprising
The first pixel electrode, the counter electrode, and the portion sandwiched between them constitute an optical resonator, the second pixel electrode, the counter electrode, and a portion sandwiched between them constitute an optical resonator, The organic EL display device in which the third pixel electrode, the counter electrode, and a portion sandwiched therebetween constitute an optical resonator.   The organic EL display device according to claim 5, wherein the second light emitting layer is provided only in a region corresponding to the second pixel electrode among the first to third pixel electrodes.   The organic EL display device according to claim 5, wherein the second light emitting layer is provided only in a region corresponding to the second and third pixel electrodes in the first to third pixel electrodes.   When observed from a direction perpendicular to the main surface of the insulating substrate, the light emitting portion corresponding to the third pixel electrode is a right-sided quadrilateral, and the light emitting portion corresponding to the first pixel electrode and the second pixel electrode The organic EL display device according to claim 7, wherein at least a part of the corresponding light emitting portion is bent along the side of the right quadrilateral. An insulating substrate;
First to third video signal lines each extending in a first direction above the insulating substrate and arranged in a second direction intersecting the first direction;
A plurality of scanning signal lines intersecting the first to third video signal lines above the insulating substrate;
A plurality of first transistors arranged above the insulating substrate so as to correspond to intersections of the plurality of scanning signal lines and the first video signal line;
A plurality of second transistors arranged above the insulating substrate so as to correspond to intersections of the plurality of scanning signal lines and the second video signal line;
A plurality of third transistors arranged above the insulating substrate so as to correspond to intersections of the plurality of scanning signal lines and the third video signal line;
A first column comprising a plurality of first pixel electrodes arranged in the first direction corresponding to the plurality of first transistors above the insulating substrate;
A second column comprising a plurality of second pixel electrodes arranged in the first direction corresponding to the plurality of second transistors above the insulating substrate and adjacent to the first column in the second direction. When,
A third column comprising a plurality of third pixel electrodes arranged in the first direction corresponding to the plurality of third transistors above the insulating substrate and adjacent to the second column in the second direction When,
It is located above the plurality of scanning signal lines, the plurality of first to third video signal lines, and the plurality of first to third transistors, and is opened at the position of the plurality of first to third pixel electrodes. The portion corresponding to the region between the first and second pixel electrodes has a tapered cross section perpendicular to the arrangement direction of the first and second pixel electrodes, and the second and third pixels A portion corresponding to a region between the electrodes has a partition insulating layer having a tapered cross section perpendicular to the arrangement direction of the second and third pixel electrodes,
A counter electrode formed above the first to third columns and the partition insulating layer;
A first light emitting layer interposed between the first to third columns and the counter electrode and extending over a region including the first to third columns;
The first light emission has a shape extending in the first direction and is provided only in a region corresponding to the second column of the first to third columns, and between the second column and the counter electrode. A second light emitting layer overlapping the layer;
The first light emission has a shape extending in the first direction and is provided only in a region corresponding to the third column of the first to third columns, and between the third column and the counter electrode. A third light emitting layer overlapping the layer,
Each of the plurality of first pixel electrodes, the counter electrode, and the portion sandwiched therebetween constitute an optical resonator, and each of the plurality of second pixel electrodes, the counter electrode, and a portion sandwiched between them Constitutes an optical resonator, and each of the plurality of third pixel electrodes, the counter electrode, and a portion sandwiched between them constitute an optical resonator. An insulating substrate;
First to third video signal lines each extending in a first direction above the insulating substrate and arranged in a second direction intersecting the first direction;
A plurality of scanning signal lines intersecting the first to third video signal lines above the insulating substrate;
A plurality of first transistors arranged above the insulating substrate so as to correspond to intersections of the plurality of scanning signal lines and the first video signal line;
A plurality of second transistors arranged above the insulating substrate so as to correspond to intersections of the plurality of scanning signal lines and the second video signal line;
A plurality of third transistors arranged above the insulating substrate so as to correspond to intersections of the plurality of scanning signal lines and the third video signal line;
A first column comprising a plurality of first pixel electrodes arranged in the first direction corresponding to the plurality of first transistors above the insulating substrate;
A second column comprising a plurality of second pixel electrodes arranged in the first direction corresponding to the plurality of second transistors above the insulating substrate and adjacent to the first column in the second direction. When,
A third column comprising a plurality of third pixel electrodes arranged in the first direction corresponding to the plurality of third transistors above the insulating substrate and adjacent to the second column in the second direction When,
It is located above the plurality of scanning signal lines, the plurality of first to third video signal lines, and the plurality of first to third transistors, and is opened at the position of the plurality of first to third pixel electrodes. The portion corresponding to the region between the first and second pixel electrodes has a tapered cross section perpendicular to the arrangement direction of the first and second pixel electrodes, and the second and third pixels A portion corresponding to a region between the electrodes has a partition insulating layer having a tapered cross section perpendicular to the arrangement direction of the second and third pixel electrodes,
A counter electrode formed above the first to third columns and the partition insulating layer;
A first light emitting layer interposed between the first to third columns and the counter electrode and extending over a region including the first to third columns;
A shape extending in the first direction, provided only in a region corresponding to the second and third columns of the first to third columns, and between the second column and the counter electrode; and A second light-emitting layer overlapping the first light-emitting layer between a third row and the counter electrode;
The first light emission has a shape extending in the first direction and is provided only in a region corresponding to the third column of the first to third columns, and between the third column and the counter electrode. A third light emitting layer overlapping the layer,
Each of the plurality of first pixel electrodes, the counter electrode, and the portion sandwiched therebetween constitute an optical resonator, and each of the plurality of second pixel electrodes, the counter electrode, and a portion sandwiched between them Constitutes an optical resonator, and each of the plurality of third pixel electrodes, the counter electrode, and a portion sandwiched between them constitute an optical resonator. The first to third pixel electrodes are anodes, the counter electrode is a cathode, the second light emitting layer is interposed between the first light emitting layer and the second pixel electrode, and the third light emitting layer the organic EL display device according to any one of claims 5 to 10 is interposed between the third pixel electrode and the first emission layer. The first portion corresponding to the first pixel electrode emits blue light, the second portion corresponding to the second pixel electrode emits green light, and the third portion corresponding to the third pixel electrode emits red light. the organic EL display device according to any one of claims 5 to 11. The organic EL display device according to any one of the first to third pixel electrodes claims 5 to 12 are equal in thickness. A hole injection layer, an electron injection layer, a hole transport layer, an organic EL display device according to any one of claims 1 to 13 further comprising at least one electron transporting layer and the hole blocking layer.

Images