JP2005293983A - Spontaneous emission display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve utilization efficiency of an EL device for an organic EL multicolor display. <P>SOLUTION: A light transmittable electrode 7, a luminescent layer 8 having a light emitting function, a metal electrode 9, antireflective films 4, and a color filter layer 3 provided corresponding to each pixel between a light transmittable substrate 2 and the light transmittable electrode 7 are formed on the substrate 2. The antireflective films 4 are formed at a periphery of a display region of the substrate 2, and formed respectively overlapped with an auxiliary wiring 6, by which luminous takeoff efficiency of the EL device is improved removing a circular polarizer, without extremely lowering a display grade with regard to the organic EL multicolor display. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a self-luminous display device such as an organic EL display.

  In order to obtain high contrast of an organic electroluminescence (hereinafter referred to as organic EL) display, there is a method of pasting a circularly polarizing plate that combines a polarizing plate and a retardation plate to the display as an antireflection measure for external light. . In this method, reflection of external light by the cathode in the display area is almost blocked by the circularly polarizing plate, while the light emission of the organic EL element itself is attenuated to the transmittance of the polarizing film (approximately 40%). The ratio (so-called contrast ratio) is very high, and has a certain effect for improving the display quality (for example, see Patent Document 1).

Furthermore, when a circularly polarizing plate is pasted, a uniform polarization state can be formed by applying a reflective layer so that the wiring pattern is difficult to see in appearance. Thereby, the opening part of a module can be unified in a substantially uniform state (for example, refer patent document 2).
JP-A-7-142170 JP 2002-203686 A

  However, when a color display is to be realized by overlaying each color filter color (RGB) on a white organic EL, in addition to the transmittance of the color filter (there is a difference depending on each color, but on average around 30%) The ON display is realized through the transmittance (about 40%) of the circularly polarizing plate. For this reason, when the method of bonding the circularly-polarizing plate which combined the polarizing plate and the phase difference plate to the above-mentioned display is employ | adopted, the problem that the utilization efficiency of an organic EL element became very bad (about 12%) arose.

  For this reason, a circularly polarizing plate is used in the prior art. However, an organic EL panel in which a circularly polarizing plate is added to the light emitting display portion has a problem that brightness is lowered although contrast is good. In this case, the contrast is improved in the non-light emitting portion. On the other hand, when the circularly polarizing plate is eliminated from the light emitting display portion, the contrast is deteriorated but the luminance is increased. In this case, the non-light emitting portion has a phenomenon that the contrast is deteriorated.

  Furthermore, since the repetitive pattern of each color filter color (RGB) formed on the display portion passes through the color filter in a reciprocating manner with respect to the external light, the OFF display looks black to some extent without attaching a circularly polarizing plate ( About 9%). However, the wiring part around the display and the dummy pad (hereinafter referred to as a non-wiring part) arranged on the premise of attaching the polarizing film reflect the metal. Therefore, it is difficult to remove the circularly polarizing plate while maintaining display quality over the entire display periphery.

  Therefore, in the present invention, with respect to the color filter type organic EL multi-color display, it is possible to remove the circularly polarizing plate while maintaining display quality by forming an antireflection film on the non-light emitting portion. That is, an object of the present invention is to increase the utilization efficiency of EL elements.

  In order to achieve the above object, a representative invention as a first solving means of an electronic device in the present application includes a light-transmitting substrate, a light-transmitting electrode formed on the substrate, and a light-transmitting property. An organic layer having a light emitting function formed on an electrode having a metal layer, a metal electrode formed so as to dispose the organic layer having a light emitting function between the light transmissive electrode, and reflection of external light An antireflective film that prevents at least a display area, and the substrate includes at least a display area and a non-display area formed around the display area, and the antireflection film is formed at least in the non-display area. It is characterized by being.

  By adopting such a configuration, the circularly polarizing plate can be removed while maintaining display quality over the entire display periphery.

  The substrate may be characterized in that at least a circularly polarizing plate is not disposed on a substrate surface opposite to a substrate surface on which a light-transmitting electrode is formed.

  The self-luminous display device includes a plurality of pixels formed in a matrix in a display region, and each pixel includes a light-transmitting electrode, an organic layer having a light-emitting function, and a metal electrode. It is good.

  By adopting such a configuration, the light extraction efficiency of the organic EL element can be extremely increased.

  The antireflection film may include a film containing at least a resin material.

  The self-luminous display device may include a protective layer formed to cover the antireflection film.

  The antireflection film may include a film containing at least a metal material.

  A color filter layer provided corresponding to each pixel between the substrate and the light-transmitting electrode, a protective layer formed so as to cover the color filter layer, and an antireflection film, at least a protective layer forming region A passivation layer that covers the entire surface of the light-transmitting substrate that is formed outside and covers the antireflection film and the protective layer may be further included.

  By adopting such a configuration, the contrast ratio is very high, and it is difficult for moisture to enter from the lead-out wiring portion.

  The self-luminous display device includes an auxiliary wiring formed on the passivation layer and electrically connected to the light-transmitting electrode, and the antireflection film is a part of the auxiliary wiring or at least a non-display area. It is good also as the characteristics arrange | positioned so that it may overlap in a part.

  By adopting such a configuration, it is possible to maintain a uniform contrast ratio between the light emitting portion and the non-light emitting portion. Further, by using the same material as the auxiliary wiring (for example, aluminum (Al) or chromium (Cr)) for the antireflection film, the antireflection film is resistant to corrosion and has a structure in which moisture does not easily enter from the lead-out wiring portion.

  A color filter layer provided corresponding to each pixel between the substrate and the light-transmitting electrode; a protective layer formed over the color filter layer; and a passivation layer covering the protective layer; The antireflection film has a film formed on the passivation layer at least outside the protective layer formation region and a film formed on the passivation layer within the protective layer formation region. The antireflection film formed on the passivation layer in the protective layer formation region may also function as an auxiliary wiring electrically connected to the light-transmitting electrode.

  The self-luminous display device covers a color filter layer provided corresponding to each pixel between a substrate and a light-transmitting electrode, a protective layer formed to cover the color filter layer, and a protective layer The antireflection film may further include at least a color filter layer.

  The self-luminous display device includes an auxiliary wiring formed on the passivation layer and electrically connected to the light-transmitting electrode, and the auxiliary wiring film electrically insulated from the auxiliary wiring is In at least a part of the non-display area, the antireflection film formed of the color filter layer may be overlapped with the antireflection film.

  There are a plurality of the antireflection films, and at least one of the antireflection films is disposed so as to overlap with the color filter layer in at least a part of the non-display area on the passivation layer. It is formed in the display region on the passivation layer, functions as an auxiliary wiring electrically connected to the light-transmitting electrode, and includes at least the same material as the antireflection film formed in the non-display region. It may be a feature.

  The self-luminous display device covers a color filter layer provided corresponding to each pixel between a substrate and a light-transmitting electrode, a protective layer formed to cover the color filter layer, and a protective layer A passivation layer, the antireflection film has a color filter layer, and the color filter layer has a structure formed by laminating at least two layers. Also good.

  The self-luminous display device includes a color filter layer provided corresponding to each pixel between a substrate and a light-transmissive electrode, a protective layer covering the color filter layer, and a protective layer The antireflection film may further include a color filter layer, and the color filter layer may be formed in the same pattern as the pixels.

  It is possible to increase the light extraction efficiency of the EL element.

  FIG. 1 is a cross-sectional view of an organic EL panel used in Example 1. The organic EL panel 1 has a plurality of pixels formed in a matrix in a display area, and includes a substrate 2, a color filter 3, an antireflection film 4, an overcoat 5, an auxiliary wiring 6, a transparent electrode 7, a light emitting layer 8, It consists of a reflective electrode 9 and a passivation layer 10.

  As the substrate 2, for example, an amorphous substrate such as glass or quartz is used. Since the substrate 2 side is usually the light extraction side, a material having high light transmittance is used. In this embodiment, a Corning 1737 glass substrate is used.

  In this embodiment, the color filter 3 is formed in the display area on the substrate 2 and enables color display by a combination of RGB colors provided corresponding to each pixel.

  Specifically, the color filter 3 is a color filter manufactured by Fujifilm Ohlin as a blue transmissive layer, a green transmissive layer, and a red transmissive layer on a glass substrate 2 made of Corning 1737. Light having a wavelength of 580 nm, green is light having a wavelength of 560 nm or more, light having a wavelength of 480 nm or less, and red is light having a wavelength of 580 nm or less. In this embodiment, the color filters 3 are formed in stripes with a width of 100 μm.

  In this embodiment, the antireflection film 4 is composed of an acrylic resin film containing a black pigment. As this resin film, a film usually used for a black mask for a liquid crystal display device may be adopted. In this embodiment, a coloring agent for blackening is added to the photosensitive resin and applied, and then a desired pattern of the antireflection film 4 is formed using a photolithography process.

  In addition, in the area | region of the board | substrate 2 in which the anti-reflective film 4 is formed, the non-wiring part is arrange | positioned and overlapped at least in the non-display area | region. That is, by forming the antireflection film 4 around the display area, it is possible to make it difficult to see the reflected light from the wiring pattern or the like in appearance. As a result, the OFF display around the display area and the display area can appear dark, and the contrast can be ensured.

  The overcoat 5 is a protective layer formed so as to cover the color filter 3 and the antireflection film 4. In this embodiment, the overcoat 5 is made of an ultraviolet curable acrylic resin and has a thickness of 1 μm.

  Then, the passivation layer 10 has a composition SiOxNy (molar ratio: x = 1.77, y = 0.26), and is formed by plasma CVD (chemical vapor phase) to a thickness of 1 μm at a deposition rate of 330 nm / min. Growth) It was formed by a film forming method. At this time, the gas pressure was 90 Pa, the temperature condition was 200 ° C., the input power was 600 W (high frequency 13.56 MHz), and the GAP was 33 mm.

  The auxiliary wiring 6 contributes to light emission emitted to the outside by partially reducing the hole charge injection efficiency by providing a metal film having a small work function as a part of the transparent electrode 7 as the auxiliary wiring 6. Don't decrease current. Furthermore, since the transparent electrode 7 and the auxiliary wiring 6 are electrically connected, the overall resistance value can be reduced and the driving voltage can be reduced. Such an organic EL element is disclosed in, for example, Japanese Patent Laid-Open No. 5-307997. In this example, Cr was formed in a stripe shape in the same manner as the color filter 3 with a film thickness of 400 nm and a line width of 20 μm so as to substantially overlap the edge on one side of the color filter 3.

Although the transparent electrode 7 is not particularly limited, in the present embodiment, it is an electrode for injecting holes, and is usually configured to take out light emitted from the substrate 2 side. Therefore, a transparent or translucent electrode is preferable. The transparent electrode 7 is not particularly limited, but ITO (tin-doped indium oxide), IZO (zinc-doped indium oxide), ZnO, SnO ₂ , In ₂ O ₃ or the like is used. Particularly preferably, ITO (tin-doped indium oxide) or IZO (zinc-doped indium oxide) is used. In this example, the transparent electrode 7 was formed so as to constitute a pixel of 256 dots × 64 lines (one pixel 300 × 300 μm) so that the transparent electrode 7 was in contact with the ITO end and overlapped with the color filter 3. At this time, the transparent electrode 7 was formed in a stripe shape with a line width of 90 μm.

  Next, a positive resist was spin-coated on the entire surface of the substrate, and then patterned so that an opening of 80 μm × 300 μm was obtained in the central portion of the transparent electrode 7. Then, after spin-coating a reverse taper resist (edge cover layer 92 described later) over the entire surface of the substrate, a positive resist is present and a reverse taper resist is formed with a line width of 10 μm so as to be orthogonal to the stripe direction of the transparent electrode 7. It was formed in a stripe shape.

And the board | substrate 2 with which the transparent electrode 7 formed in the stripe form was formed was ultrasonically cleaned using a medieval detergent, dried, and then UV / O ₃ cleaned. Next, the substrate 2 was moved to a vacuum film formation chamber, fixed with a vacuum deposition substrate holder, and the inside of the tank was depressurized to 1 × 10 −4 Pa or less.

  Further, while maintaining the reduced pressure state, N, N′-diphenyl-N, N′-bis (N- (4-methylphenyl) -N-phenyl (4-aminophenyl))-1,1-bisphenyl- 4,4-diamine was formed to a thickness of 40 nm at a deposition rate of 0.1 nm / sec. While maintaining the reduced pressure state, N, N′-diphenyl-N, N′-bis (1-naphthyl) -1,1′-diphenyl-4,4′-diamine was deposited at a deposition rate of 0.1 nm / sec to 10 nm. The thickness was formed.

For the light emitting layer 8, a fluorescent material which is a compound having a light emitting function is used. Such a fluorescent substance is composed of, for example, the following compounds 1 to 4.

  Specifically, the compound 1 and the compound 2 were co-deposited at a volume ratio of 100: 3 and a deposition rate of 0.1 nm / sec as the light emitting layer 8 while maintaining the reduced pressure state, and formed to a thickness of 10 nm. .

  Further, while maintaining the reduced pressure state, Compound 3 and Compound 4 were co-deposited at a volume ratio of 100: 3 and a deposition rate of 0.1 nm / sec to form a thickness of 30 nm as the light emitting layer 8.

  The reflective electrode 9 is not particularly limited, but in the present embodiment, it is an electrode for injecting electrons, and a substance having a low work function is preferable. For example, there are simple metal elements such as K, Li, Na, Mg, La, Ce, Ca, Sr, Ba, Al, Ag, In, Sn, Zn, and Zr. In order to improve the stability, it is preferable to use a two-component or three-component alloy system containing them. Examples of the alloy system include Ag · Mg (Ag: 0.1 to 50 at%), Al·Li (Li: 0.01 to 14 at%), In · Mg (Mg: 50 to 80 at%), Al · Ca ( Ca: 0.01 to 20 at%) is preferable.

  The reflective electrode 9 can be formed by vapor deposition or sputtering. The thickness of the reflective electrode 9 may be a certain thickness that can sufficiently inject electrons, and may be 0.1 nm or more, preferably 1 nm or more. Moreover, although there is no restriction | limiting in particular in the upper limit, A normal film thickness should just be about 1-500 nm.

  Specifically, in this example, IDE 120 was formed to a thickness of 30 nm at a deposition rate of 0.1 nm / sec. LiF was formed to a thickness of 0.7 nm at a deposition rate of 0.01 nm / sec while maintaining the reduced pressure state. Further, while maintaining the reduced pressure state, Al was formed as the reflective electrode 9 to a thickness of 300 nm at a deposition rate of 0.8 nm / sec.

  In the organic EL element, excitons are generated in the light-emitting layer 8 due to recombination of holes injected from the transparent electrode 7 and electrons injected from the metal electrode 4, and the excitons are recombined. Light is emitted, and the light passes through the transparent electrode 7 and the substrate 2 and is emitted to the outside. Therefore, by using the transparent electrode 7 having a high work function and the reflective electrode 9 having a low work function, the charge injection efficiency is increased, and the light emission efficiency of the light emitting layer 8 is improved.

Specifically, in this embodiment, the organic EL panel 1 is formed in a pattern of 256 × 64 dots (pixels), driven with a line sequential drive voltage of 15 V, and without a color filter and a circularly polarizing plate in a dark room. Chromaticity X: 0.32 and chromaticity Y: 0.36 were realized with white light emission of 250 cd / m ² .

  In this embodiment, the antireflection film 4 is formed in the overlapping portion of the wiring around the display area, thereby realizing a low reflection of the display panel. Furthermore, since the antireflection film 4 is also disposed in the non-light emitting portion where there is no wiring around the display area, low reflection can be realized. As a result, the circularly polarizing plate that was originally required becomes unnecessary. As a result, it is not necessary to emit light as much as it is absorbed by the circularly polarizing plate, thereby extending the lifetime of the module and leading to cost reduction by removing the circularly polarizing plate.

  2A and 2B are cross-sectional views of the organic EL panel used in Example 2. FIG. FIG. 2A shows a cross section of the organic EL panel 1, and FIG. 2B shows a cross section of the wiring portion of the organic EL panel 1.

  Here, the present embodiment is different from the first embodiment in that the antireflection film 4 is composed of a black film containing a metal material having high conductivity. The antireflection film 4 is, for example, a film containing carbon, a film in which a black pigment / dye is dispersed and mixed in a base material, or a metal compound (that is, oxide, nitride, sulfide, boride, etc.), Alternatively, a mixture thereof can be used. Specifically, in this embodiment, Cr, Cr oxide or a laminated antireflection film 4 is used.

  In this embodiment, the antireflection film 4 is formed at least in a region where the overcoat 5 is not formed, as shown in FIG. Further, as shown in FIG. 2B, the auxiliary wiring 6 outside the display area is formed so as to overlap with the antireflection film 4 through the passivation layer 10. Thus, the antireflection film 4 overlaps with the same shape as the wiring pattern of the auxiliary wiring 6.

  The antireflection film 4 extends to the lead-out wiring portion, but the passivation layer 10 exists on the antireflection film 4 and the auxiliary wiring 6 is formed thereon. Therefore, the antireflection film 4 is not electrically connected. Therefore, the stray capacitance formed between the antireflection film 4 and the lead-out wiring does not apply a potential to the antireflection film 4, so that no charge is accumulated. For this reason, no extra charge is charged or discharged during driving, and display quality is not deteriorated.

  The antireflection film 4 has a stripe shape in this figure. When the antireflection film 4 is formed in a planar shape, the antireflection film 4 and the lead-out wiring have the same relationship as the series of two capacitors. This is to prevent this. If the antireflection film 4 and the lead-out wiring are in a capacitor relationship, a charge corresponding to the difference in potential between the anti-reflection film 4 and the lead-out wiring is accumulated, and the display quality is deteriorated. In order to prevent this, in this embodiment, the antireflection film 4 has a stripe or line configuration.

  By adopting such a configuration for the antireflection film, uniform low reflection can be realized for the entire panel, and the contrast ratio becomes very high. As a result, the circularly polarizing plate that was originally required becomes unnecessary. As a result, it is not necessary to emit light as much as it is absorbed by the circularly polarizing plate, thereby extending the lifetime of the module and leading to cost reduction by removing the circularly polarizing plate.

  3A and 3B are cross-sectional views of the organic EL panel used in Example 3. FIG. The present embodiment is different from the first embodiment in that the color filter 3 functions as an antireflection film. Further, as shown in FIG. 3A, the auxiliary wiring film 6 outside the display area is disposed on the overcoat 5 and the passivation layer 10.

  In FIG. 3A, the color filter 3 and the auxiliary wiring film 6 are uniformly arranged in many areas of both the display area and the non-display area. Thereby, the display is homogenized over the entire display surface. Therefore, in this embodiment, the contrast ratio can be kept uniform between the light emitting portion and the non-light emitting portion.

  FIG. 3B shows a case where the auxiliary wiring film 6 outside the display area is not formed on the passivation layer 10. In this case, the color filter 3 functions as the antireflection film 4. That is, the color filter 3 is configured to make it difficult to see the reflected light from the wiring pattern or the like in appearance. As a result, the OFF display around the display area and the display area can appear dark, and the contrast can be ensured.

  When the color filter 3 functions as the antireflection film 4, the color filter 3 may be formed by stacking at least two layers. By configuring in this way, it is possible to further prevent reflection of external light as compared with the case where the color filter 3 is a single layer.

  Specifically, in the case of area color display in which two or more color filters 3 are used, at least two color filters 3 that function as the antireflection film 4 can be formed. On the other hand, in the case of full color, the function as the antireflection film 4 can be improved by forming the color filter 3 into three layers.

  In this case, there is a merit of using the color filter 3 that has been laminated and thickened as a sealing spacer. The color filter 3 needs to be formed thicker (for example, 2 μm or more) than the edge cover layer 92 and the separator layer 102.

  Furthermore, the color filter 3 may be formed in the same pattern as the formation pattern of each pixel in the display area. By forming in this way, the contrast ratio inside and outside the display region can be maintained more uniformly.

  4A and 4B are cross-sectional views of the organic EL panel used in Example 4. FIG. FIG. 4A shows a cross section of the organic EL panel 1, and FIG. 4B shows a cross section of the wiring portion of the organic EL panel 1.

  Here, the present embodiment is different from the first embodiment in that the antireflection film 4 is composed of a black film containing a metal material having high conductivity. The antireflection film 4 is, for example, a film containing carbon, a film in which a black pigment / dye is dispersed and mixed in a base material, or a metal compound (that is, oxide, nitride, sulfide, boride, etc.), Alternatively, a mixture thereof can be used.

  In this embodiment, as shown in FIG. 4A, the antireflection film 4 is formed on the passivation layer 10 and in a region where the overcoat 5 is not formed. In addition, as shown in FIG. 4B, the auxiliary wiring 6 in the display area is formed as an antireflection film 4. That is, in this embodiment, the auxiliary wiring 6 is composed of the antireflection film 4 itself.

  Alternatively, the antireflection film 4 may be made of a metal film having a small work function such as aluminum, magnesium, indium, silver, or an alloy thereof in order to fulfill the function of the auxiliary wiring 6. Specifically, in this embodiment, Cr, Cr oxide or a laminated antireflection film 4 is used.

  With this configuration, in this embodiment, the color filter 3 and the antireflection film 4 are uniformly arranged in both the display area and the non-display area, thereby uniforming the display. Display quality is improved. As a result, the circularly polarizing plate that was originally required becomes unnecessary.

  5A and 5B are cross-sectional views of the organic EL panel used in Example 5. FIG. FIG. 5A shows a cross section of the organic EL panel 1, and FIG. 5B shows a cross section of the wiring portion of the organic EL panel 1.

  Here, the present embodiment is different from the first embodiment in that the color filter 3 functions as the antireflection film 4. Further, the antireflection film 4 outside the display area is disposed on the overcoat 5 and the passivation layer 10, and the antireflection film 4 in the display area also functions as the auxiliary wiring 6.

  With this configuration, in this embodiment, the color filter 3 and the antireflection film 4 are uniformly arranged in many areas of both the display area and the non-display area. Thereby, the display is homogenized over the entire display surface, and the display quality is improved. As a result, the circularly polarizing plate that was originally required becomes unnecessary.

  In this embodiment, the antireflection film 4 is preferably a black film containing a metal material having high conductivity. For example, a film containing carbon or a black pigment / dye is dispersed and mixed in the base material. A film, a metal compound (that is, oxide, nitride, sulfide, boride, or the like), or a mixture thereof can be used. Specifically, in this embodiment, Cr, Cr oxide or a laminated antireflection film 4 is used.

  In this embodiment, there is an effect that the contrast ratio can be kept uniform between the light emitting portion and the non-light emitting portion. Further, the antireflection film 4 can be resistant to corrosion and can have a structure in which moisture hardly enters from the lead-out wiring portion.

  FIG. 6 shows the manufacturing process of the organic EL panel used in this embodiment. Although the glass substrate is used for the substrate 2 in this embodiment, the present invention is not limited to this, and another amorphous substrate such as quartz may be used.

  In the present embodiment, a passivation layer 10 is formed on the substrate 2. This is because a glass substrate is used as the substrate 2, and thus impurities from the substrate 2 are prevented from entering the film formation side. The cross section 60 shows the A-A ′ cross section of the substrate 2, and the cross section 61 shows the B-B ′ cross section of the substrate 2.

  Various wirings or layers to be described later are formed on the substrate 2 by vapor deposition, sputtering, plasma CVD (chemical vapor deposition) or the like. In the present embodiment, the color filter 3 is not shown.

  FIG. 7 shows a manufacturing process of the organic EL panel used in this embodiment. This step is a step of forming the auxiliary wiring 6 on the substrate 2 shown in FIG. The auxiliary wiring 6 is not particularly limited, but in this embodiment, aluminum is adopted as a metal film having a small work function. Specifically, aluminum is formed as a wiring electrode with a film thickness of 300 nm on the glass substrate 2 by sputtering, and patterning is performed by photolithography. Alternatively, Al—Ti (2 wt%) / TiN may be used. A section 70 shows an A-A ′ section of the substrate 2, and a section 71 shows a B-B ′ section of the substrate 2. The auxiliary wiring 6 is formed by patterning shown in the cross section 71.

  FIG. 8 shows a manufacturing process of the organic EL panel used in this embodiment. This step is a step of forming the transparent electrode 7 on the substrate 2 shown in FIG. The transparent electrode 7 is not particularly limited, but ITO (tin-doped indium oxide) is used in this embodiment. Specifically, in this step, an ITO film with a thickness of about 100 nm was formed by sputtering. The obtained ITO thin film was patterned and etched by photolithography to form a transparent electrode 7 constituting a 256 × 64 dot (pixel) pattern. A cross section 80 shows an A-A ′ cross section of the substrate 2, and a cross section 81 shows a B-B ′ cross section of the substrate 2. The transparent electrode 7 partially overlaps the auxiliary wiring 6 as shown in the cross section 81 and is electrically connected at this portion. Since the transparent electrode 7 and the auxiliary wiring 6 are electrically connected in this way, the overall resistance value can be reduced and the drive voltage can be lowered.

  In the present embodiment, the transparent electrode 7 is formed so that the light transmittance for each light emission is 50% or more, preferably 60% or more in the emission wavelength band (usually 350 to 800 nm). This is because the emitted light is extracted through the transparent electrode 7, so that if the transmittance is lowered, the emitted light itself from the light emitting layer is attenuated and the luminance necessary for the light emitting element cannot be obtained. However, when the emitted light is taken out from only one side, the side to be taken out may be more than the above.

  In the present embodiment, the thickness of the transparent electrode 7 is sufficient if it has a certain thickness that can sufficiently inject holes, and is preferably in the range of 50 to 500 nm, more preferably 50 to 300 nm. The upper limit is not particularly limited, but if it is too thick, there is a concern about peeling. If the thickness is too thin, there are problems in terms of film strength, hole transport capability, and resistance value during manufacture. The transparent electrode 7 can be formed by vapor deposition or the like, but is preferably formed by sputtering.

  FIG. 9 shows a manufacturing process of the organic EL panel used in this embodiment. This step is a step of forming the edge cover layer 92 on the transparent electrode 7 shown in FIG. A cross section 90 shows an A-A ′ cross section of the substrate 2, and a cross section 91 shows a B-B ′ cross section of the substrate 2. In this embodiment, as shown in the cross sections 90 and 91, the edge cover layer 92 is formed by spin coating the edge cover layer 92 using a photoresist except for the opening 93 where the light emitting portion is formed. In this embodiment, the opening 93 is formed so as to form a pattern of 256 × 64 dots (pixels).

  FIG. 10 shows a manufacturing process of the organic EL panel used in this example. This step is a step of forming the separator layer 102 on the edge cover layer 92 shown in FIG. A cross section 100 shows an A-A ′ cross section of the substrate 2, and a cross section 101 shows a B-B ′ cross section of the substrate 2. In the present embodiment, as shown in the cross section 100, the separator layer 102 is formed so that the separator layer 102 overlaps the edge cover layer 92 using a photoresist, except for the opening 93 where the light emitting portion is formed. The reverse taper resist is spin-coated and patterned in a stripe shape in a direction substantially perpendicular to the ITO stripe direction.

  FIG. 11 shows a manufacturing process of the organic EL panel used in this embodiment. This step is a step of forming the light emitting layer 8 and the reflective electrode 9 in the opening 93 shown in FIG. A cross section 110 shows an A-A ′ cross section of the substrate 2, and a cross section 111 shows a B-B ′ cross section of the substrate 2.

  In the present embodiment, although not particularly limited, the light emitting layer 8 and the reflective electrode 9 may be formed by using the manufacturing method described in Patent Document 2. The light emitting layer 8 is formed by a vacuum vapor deposition apparatus, and the reflective electrode 9 is moved from the vacuum vapor deposition apparatus to the sputtering apparatus, and formed as shown in the cross section 110 and the cross section 111, respectively.

  FIGS. 12A and 12B are conceptual diagrams of an organic EL display used in this embodiment. FIG. 12A is a plan view of the organic EL display 120, and FIG. 12B is a cross-sectional view taken along the line C-C ′ of FIG. As shown in FIG. 12B, in the organic EL display 120, a sealing substrate 121 is bonded to the organic EL panel 1, and a sealing gas is filled between the substrates. This is to prevent deterioration of the organic layer and the electrode. In order to prevent moisture from entering, the sealing substrate 121 uses an adhesive resin 127 in the sealing material region 122 shown in FIG. 121 is bonded to the substrate 2 and sealed.

Sealing gas, Ar, He, an inert gas such as _{N 2} is preferable. The moisture content of the sealing gas is preferably 100 ppm or less, more preferably 10 ppm or less, and particularly preferably 1 ppm or less. Although there is no lower limit for this moisture content, it is usually about 0.1 ppm, and a desiccant 126 is affixed to the sealing substrate 121 as shown in FIG.

  As shown in FIG. 12A, the organic EL display 120 has a cathode lead-out wiring 123 and an anode lead-out wiring 124. The connection between the cathode lead-out wiring 123 and the reflective electrode 9 is shown in FIG. As shown, the contact pad formation region 125 is performed with a contact pad.

  In this embodiment, although not shown, the antireflection film 4 is formed under the auxiliary wiring 6 disposed in the display area inside the sealing material area 122. Further, in this embodiment, the antireflection film 4 is also formed under the cathode lead-out wiring 123 and the anode lead-out wiring 124 arranged in the non-display area outside the seal material area 122. In addition, the direction which improved the contrast in the place close | similar to a light emission area can exhibit the high contrast of the organic electroluminescent panel 1 whole. Therefore, it is essential that the antireflection film 4 is disposed in the display area inside the sealing material area 122. The antireflection film 4 is composed of a black film containing a metal material having high conductivity.

  FIG. 13 is a conceptual diagram of a self-luminous display device used in this embodiment. The self-luminous display device 130 is configured by attaching a scanning signal driver IC 131, a scanning signal driver circuit 132, a video signal driver IC 133, a video signal driver circuit 134, an FPC 135, and a controller 136 to an organic EL display 120.

  The scanning signal driver IC 131 is a driver that transmits a signal to the cathode lead-out wiring 123, and includes a scanning signal driver circuit 132. The video signal driver IC 133 is a driver that transmits a signal to the anode lead-out wiring 124 and includes a video signal driver circuit 134. Each driver circuit is connected to the controller 136 via the FPC 135. The controller 136 is a controller that controls display data displayed on the organic EL display 120.

  FIG. 14 is a bird's-eye view showing the manufacturing process of the organic EL display used in this embodiment. In addition, the organic EL display 120 of a present Example is a bird's-eye view of the organic EL display 120 demonstrated in FIG. 12, and is formed in the same process.

  Specifically, the color filter 3, the auxiliary wiring 6, and the transparent electrode 7 are respectively formed on the substrate 2 (a passivation layer is formed when alkali glass is used as the substrate 2) as shown in FIG. Has been placed. And the edge cover layer 92 is coat | covered on it except the opening part 93 and the sealing material. Between the color filter 3 and the auxiliary wiring 6, an overcoat 5 is formed as a protective layer, and a passivation layer (not shown) is formed when alkali glass is used as the substrate 2.

  The detailed description of each pixel is as follows. As shown in the enlarged pixel view 140, the edge cover layer 92 is covered on the transparent electrode 7 electrically connected to the auxiliary wiring 6, and the opening 93 is opened. In this embodiment, such pixels are configured by 256 × 64 pixels to realize the organic EL display 120 for color display.

  The auxiliary wiring 6 is not particularly limited, but is electrically connected to the anode lead-out wiring 124 in this embodiment. The cathode lead-out wiring 123 is patterned in accordance with the contact pad formation region 125. In this drawing, the contact pad formation region 125 is a portion that is covered with the cathode lead-out wiring 123 by the edge cover layer 92 and is opened at a part of the cathode lead-out wiring 123.

  Although not shown, the antireflection film 4 is formed under the cathode lead-out wiring 123 and the anode lead-out wiring 124 disposed in the non-display area outside the display area in this embodiment. Further, in this embodiment, the antireflection film 4 is made of a film containing a black and high conductivity metal material.

  FIG. 15 is a bird's-eye view showing the manufacturing process of the organic EL display used in this embodiment. In this step, the step of forming the separator layer 102 on the edge cover layer 92 shown in FIG. 14 is shown. As shown in the drawing, the separator layer 102 is formed in a linear shape so as to be orthogonal to the anode lead-out wiring 124.

  FIG. 16 is a bird's-eye view showing the manufacturing process of the organic EL display used in this embodiment. In this step, the step of forming the light emitting layer 8 and the reflective electrode 9 on the separator layer 102 shown in FIG. 15 is shown. The light emitting layer 8 and the reflective electrode 9 are linearly formed in a groove formed between the separator layers 102 so as to be orthogonal to the anode lead-out wiring 124.

Note that after the reflective electrode 9 is formed, a protective film using an inorganic material such as SiO _x, an organic material such as Teflon (registered trademark), a fluorocarbon polymer containing chlorine, or the like may be formed. The protective film may be transparent or opaque, and the thickness of the protective film is about 50 to 1200 nm. The protective film may be formed by a general sputtering method, vapor deposition method, plasma CVD (chemical vapor deposition) or the like in addition to the reactive sputtering method.

  FIG. 17 is a bird's-eye view showing the manufacturing process of the organic EL display used in this embodiment. In this step, the step of bonding the sealing substrate 121 on the substrate 2 shown in FIG. 14 is shown.

  The substrate 2 is bonded to the sealing substrate 121 through an adhesive resin layer 127 as shown in the figure. A desiccant 126 is attached to the sealing substrate 121 on the substrate 2 side. The desiccant 126 illustrated in the figure is an uneven portion provided for disposing the desiccant 126, and the desiccant 126 itself is provided on the side of the sealing substrate 121 facing the substrate 2. .

FIG. 18 is a diagram for comparing the display characteristics of the present embodiment. In this figure, the organic EL panel 1 of this example is driven at a line sequential drive voltage of 15 V, and a white light emission of 250 cd / m ^{2 in} a dark room without a color filter and a circularly polarizing plate has a chromaticity X of 0.32. The chromaticity Y is 0.36, and the contrast in the display area and the periphery of the display area of the organic EL panel 1 is compared. The measurement conditions of this example are: external light 500 lx, color filter average transmittance 30%, circular polarizer transmittance 42%, polarization degree 99.9%, antireflection film reflectance 5%, cathode, auxiliary wiring reflectance 60 %.

  Specifically, the organic EL panel 1 used for comparison in the figure is a color filter 3 on a Corning 1737 glass substrate 2 with a blue transmissive layer, a green transmissive layer, and a red transmissive layer, as Fujifilm Ohlin. A color filter made of blue, with cut light having a wavelength of 490 nm or more, green having a wavelength of 560 nm or more, light having a wavelength of 480 nm or less, and red having a wavelength of 580 nm or less is used. In this embodiment, the color filters 3 are formed in a stripe shape with a width of 100 μm.

  On top of this, an overcoat 5 is formed with a thickness of 1 μm using an ultraviolet curable acrylic resin. Next, the passivation layer 10 is formed with a composition SiOxNy (molar ratio: x = 1.77, y = 0.26) by a P-CVD film forming method, and is formed to a thickness of 1000 nm at a film forming speed of 330 nm / min. Yes. At this time, the gas pressure was 90 Pa, the temperature condition was 200 ° C., the input power was 600 W (high frequency 13.56 MHz), and the GAP was 33 mm.

  In comparison in this figure, samples A to I having different panel configurations are compared. The measurement results of the spot color and contrast of each sample are as follows.

  The sample A uses the color filter 3, the circularly polarizing plate, and the antireflection film 4 for the organic EL panel 1 in which each is not arranged. That is, the sample A is not the organic EL panel 1 including the present invention. In sample A, the ON luminance in the display area is the highest at 345.5, but the OFF luminance in the display area is the highest at 95.5. Therefore, ON / OFF (contrast ratio) in the display area is the worst value of 3.62. The OFF brightness around the display area is as bad as 95.5, and the ON / OFF (contrast ratio) around the display area is also very bad at 3.62. That is, from these results, in sample A, the ON brightness in the display area is high, but the OFF brightness in the display area and the periphery of the display area becomes very high. As a result, the sample A is a low-contrast display panel. Understand. In other words, it cannot be used as a display.

  Sample B uses the organic EL panel 1 in which the color filter 3 and the antireflection film 4 are not arranged. Since the circularly polarizing plate is disposed, the sample B is not the organic EL panel 1 including the present invention. In the sample B, the ON luminance in the display area is as high as 105, and the OFF luminance in the display area is very good as 0.04. Therefore, ON / OFF (contrast ratio) in the display area is very good at 2619. The OFF luminance around the display area is as good as 0.04, and the ON / OFF (contrast ratio) around the display area is as good as 2619. That is, from these results, it can be understood that the conventional theory that sample B is useful for improving the contrast ratio to some extent in Sample B is correct.

  Sample C uses an organic EL panel 1 in which a circularly polarizing plate and an antireflection film 4 are not arranged. That is, the sample C is not the organic EL panel 1 including the present invention. In the sample C, the color filter 3 is arranged. In sample C, the ON brightness in the display area is relatively good at 83.6, but the OFF brightness in the display area is not so good as 8.6, but the ON / OFF (contrast ratio) in the display area is not good. , 9.73, which is a practical range. The OFF luminance around the display area is very low at 95.5, and the ON / OFF (contrast ratio) around the display area is the worst at 0.88. That is, from these results, it can be seen that in Sample C, it is very difficult to obtain contrast around the display area unless the circularly polarizing plate or the antireflection film 4 is arranged.

  The sample D uses the organic EL panel 1 in which the antireflection film 4 is not disposed. In the sample D, the color filter 3 and the circularly polarizing plate are arranged. That is, the sample D is not the organic EL panel 1 including the present invention. In this sample, in order to ensure sufficient luminance, it is necessary to ensure sufficient luminance of the light emitting element, and there is a problem that the life of the light emitting element is short. In the sample D which is a conventional color filter type color panel, the ON luminance in the display area is as bad as 31.5, but the OFF luminance in the display area is the lowest as 0.0036. Therefore, ON / OFF (contrast ratio) in the display area is the highest value of 8728. This value is a surprising value that is more than three times that of the second highest sample B. The OFF brightness around the display area is as low as 0.04, and the ON / OFF (contrast ratio) around the display area is very good at 785.49. That is, from these results, in Sample D, the contrast ratio is good in and around the display area, but the luminance in the display area is insufficient, and it is necessary to increase the luminance in practice.

  Sample E uses the organic EL panel 1 described in Examples 1, 2, and 4. That is, the sample E is the organic EL panel 1 including the present invention. In sample E, the ON brightness in the display area is relatively good at 83.6 and the OFF brightness in the display area is not so good as 8.6, but the ON / OFF (contrast ratio) in the display area is It is within a practical range as 9.73. The OFF luminance around the display area is 8.0, and the ON / OFF (contrast ratio) around the display area is 10.5. That is, from these results, it can be seen that Sample E is a practically balanced panel from the viewpoint of both luminance and contrast.

  The sample F uses the organic EL panel 1 described in the third embodiment. That is, the sample F is the organic EL panel 1 including the present invention. In sample F, the ON luminance in the display area is relatively good at 83.6 and the OFF luminance in the display area is not so good as 8.6, but the ON / OFF (contrast ratio) in the display area is It is within a practical range as 9.73. The OFF luminance around the display area is as low as 8.6, and the ON / OFF (contrast ratio) around the display area is 9.73, which is better than that of the sample E. That is, from these results, in Sample F, the uniform arrangement of the color filter 3, the antireflection film 4, the overcoat 5, and the passivation layer 10 is useful for improving the contrast ratio including the periphery of the display area. Understand.

  The sample G uses the organic EL panel 1 described in the fifth embodiment. That is, the sample G is the organic EL panel 1 including the present invention. In sample G, the ON brightness in the display area is relatively good at 83.6 and the OFF brightness in the display area is not so good as 8.6, but the ON / OFF (contrast ratio) in the display area is It is within a practical range as 9.73. The OFF luminance around the display area is as low as 0.7, and the ON / OFF (contrast ratio) around the display area is 116.72, which is better than that of the sample E. That is, from these results, it can be seen that in sample G, the uniform arrangement of the color filter 3 and the antireflection film 4 is useful for improving the contrast ratio including the periphery of the display area.

  The sample H uses the organic EL panel 1 in which a smoke film having a transmittance of 70% is arranged in Examples 1, 2, and 4. That is, the sample H is the organic EL panel 1 including the present invention. In sample H, the ON luminance in the display area is relatively good at 56.7, and the OFF luminance in the display area is 4.2, which is better than that of sample E. Therefore, the ON / OFF (contrast ratio) in the display area may be a practical range of 13.47, the OFF luminance around the display area is 3.9, and the ON / OFF (contrast ratio) around the display area is 14.54. That is, it can be seen from these results that the sample H has a good balance of the contrast ratio in the display area and the periphery of the display area.

  Sample I uses the organic EL panel 1 in which a smoke film having a transmittance of 70% is disposed in Example 5. That is, the sample I is the organic EL panel 1 including the present invention. In sample I, the ON luminance in the display area is relatively good at 56.7, and the OFF luminance in the display area is 4.2, which is better than that of sample G. The ON / OFF (contrast ratio) in the display area is 13.47, the OFF luminance around the display area is 0.4, and the ON / OFF (contrast ratio) around the display area is 161.6. . That is, from these results, it can be seen that Sample I is useful for improving the contrast ratio around the display area.

  In the present invention, various modifications can be made as necessary. For example, in the manufacturing process, the antireflection film 4, the overcoat 5, the auxiliary wiring 6, the transparent electrode 7, the light emitting layer 8, and the reflective electrode 9 are used. Or the film thickness of the passivation layer 10, an arrangement pattern, etc. are not limited to this, A various change is possible.

  For example, the thickness of the transparent electrode 7 only needs to have a certain thickness or more that can sufficiently inject holes, and the present invention can be applied to organic EL panels having various electrode configurations. The same applies to the thickness of the reflective electrode 9 and the like.

  Further, an antireflection film (black matrix) corresponding to each pixel may be formed in the peripheral region of each pixel in the color filter existence region of the area where the pixel is formed. In this case, the antireflection film (black matrix) is formed in a matrix in the peripheral region of each pixel, as used in a normal liquid crystal display device.

  Needless to say, a display device using a light-emitting element different from the light-emitting element described in this embodiment can be applied to the present invention. For example, even if a display device using a fluorescence conversion method is used in the present invention, the same effect can be exhibited. As display devices using a fluorescence conversion method, there are those described in Japanese Patent Application Laid-Open Nos. 5-258860 and 2000-91071. When an organic light emitting device is used as a light source, the contrast ratio can be further improved by using the present invention.

  INDUSTRIAL APPLICABILITY The present invention relates to an image display device represented by organic EL image display, and can be used for color displays such as portable devices and TVs.

1 is a cross-sectional view of an organic EL panel used in Example 1. FIG. 6 is a cross-sectional view of an organic EL panel used in Example 2. FIG. 6 is a cross-sectional view of an organic EL panel used in Example 3. FIG. 6 is a cross-sectional view of an organic EL panel used in Example 4. FIG. 10 is a cross-sectional view of an organic EL panel used in Example 5. FIG. The manufacturing process of the organic electroluminescent panel used for a present Example is shown. The manufacturing process of the organic electroluminescent panel used for a present Example is shown. The manufacturing process of the organic electroluminescent panel used for a present Example is shown. The manufacturing process of the organic electroluminescent panel used for a present Example is shown. The manufacturing process of the organic electroluminescent panel used for a present Example is shown. The manufacturing process of the organic electroluminescent panel used for a present Example is shown. It is a conceptual diagram of the organic electroluminescent display used for a present Example. It is a conceptual diagram of the self-luminous type display apparatus used for a present Example. It is a bird's-eye view which shows the manufacturing process of the organic electroluminescent display used for a present Example. It is a bird's-eye view which shows the manufacturing process of the organic electroluminescent display used for a present Example. It is a bird's-eye view which shows the manufacturing process of the organic electroluminescent display used for a present Example. It is a bird's-eye view which shows the manufacturing process of the organic electroluminescent display used for a present Example. It is a figure which compares the display characteristic of a present Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Organic EL panel 2 Board | substrate 3 Color filter 4 Antireflection film 5 Overcoat 6 Auxiliary wiring, auxiliary wiring film 7 Transparent electrode 8 Light emitting layer 9 Reflective electrode 10 Passivation layer 60 AA 'cross section 61 BB' cross section 70 A- A ′ section 71 BB ′ section 80 AA ′ section 81 BB ′ section 90 AA ′ section 91 BB ′ section 92 Edge cover layer 93 Opening 100 AA ′ section 101 BB 'Cross section 102 Separator layer 110 AA' section 111 BB 'section 120 Organic EL display 121 Sealing substrate 122 Sealing material area 123 Cathode extraction wiring 124 Anode extraction wiring 125 Contact pad formation area 126 Desiccant 127 Adhesive resin layer 130 Self-luminous display device 131 Scan signal driver IC
132 Scanning Signal Driver Circuit 133 Video Signal Driver IC
134 Video signal driver circuit 135 FPC
136 Controller 140 Pixel enlarged view

Claims (14)

A substrate having optical transparency;
A light transmissive electrode formed on the substrate;
An organic layer having a light emitting function formed on the light-transmitting electrode;
A metal electrode formed so as to dispose the organic layer having the light emitting function between the electrode having light transmittance;
An antireflection film that prevents reflection of outside light, and
The substrate comprises at least a display area and a non-display area formed around the display area,
The self-luminous display device, wherein the antireflection film is formed at least in the non-display area.   2. The self-luminous display according to claim 1, wherein a circularly polarizing plate is not disposed at least on a substrate surface facing the substrate surface on which the light-transmissive electrode is formed. apparatus. The self-luminous display device has a plurality of pixels formed in a matrix in the display area,
3. The self-luminous display device according to claim 1, wherein each pixel includes the light-transmissive electrode, the organic layer having the light emitting function, and the metal electrode.   The self-luminous display device according to any one of claims 1 to 3, wherein the antireflection film includes a film containing at least a resin material.   The self-luminous display device according to claim 4, wherein the self-luminous display device includes a protective layer formed to cover the antireflection film.   The self-luminous display device according to any one of claims 1 to 3, wherein the antireflection film includes a film containing at least a metal material. A color filter layer provided corresponding to each pixel between the substrate and the light-transmissive electrode;
A protective layer formed to cover the color filter layer;
The antireflection film is formed at least outside the formation region of the protective layer,
The self-luminous display device according to claim 6, further comprising a passivation layer covering the antireflection film and the protective layer over the entire surface of the light transmissive substrate. The self-luminous display device is formed on the passivation layer and electrically connected to the light-transmissive electrode;
The self-luminous display device according to claim 7, wherein the antireflection film is disposed so as to overlap a part of the auxiliary wiring or at least a part of the non-display area. A color filter layer provided corresponding to each pixel between the substrate and the light-transmissive electrode;
A protective layer formed over the color filter layer and a passivation layer covering the protective layer,
The antireflection film has a film formed on the passivation layer at least outside the formation region of the protective layer, and a film formed on the passivation layer in the formation region of the protection layer. The antireflection film formed on the passivation layer in the protective layer formation region also functions as an auxiliary wiring electrically connected to the light-transmitting electrode. The self-luminous display device according to claim 6. The self-luminous display device includes a color filter layer provided corresponding to each pixel between the substrate and the light-transmissive electrode, a protective layer formed to cover the color filter layer, and the A passivation layer covering the protective layer,
The self-luminous display device according to claim 1, wherein the antireflection film includes at least the color filter layer. The self-luminous display device has an auxiliary wiring formed on the passivation layer and electrically connected to the light-transmissive electrode,
The auxiliary wiring film electrically insulated from the auxiliary wiring is disposed to overlap with the antireflection film formed of the color filter layer at least in a part of the non-display area. Item 11. The self-luminous display device according to Item 10.   There are a plurality of the antireflection films, and at least one of the antireflection films is disposed so as to overlap with the color filter layer in at least a part of the non-display area on the passivation layer, and at least the other antireflection film. Is formed in the display region on the passivation layer and functions as an auxiliary wiring electrically connected to the light-transmissive electrode, and is the same as the antireflection film formed in the non-display region The self-luminous display device according to claim 10, comprising at least a material. The self-luminous display device includes a color filter layer provided corresponding to each pixel between the substrate and the light-transmissive electrode, a protective layer formed to cover the color filter layer, and the A passivation layer covering the protective layer,
13. The antireflection film includes the color filter layer, and the color filter layer has a structure formed by stacking at least two layers. The self-luminous display device according to claim 1. The self-luminous display device includes a color filter layer provided corresponding to each pixel between the substrate and the light-transmitting electrode, a protective layer covering the color filter layer, and the protection A passivation layer covering the layer, and
The self-reflection film according to any one of claims 10 to 12, wherein the antireflection film has the color filter layer, and the color filter layer is formed in the same pattern as a pixel. Light-emitting display device.

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