Display device

Abstract

Provided is a display device with which it is possible to control the viewing angle.　A display device according to one embodiment comprises: a substrate; an insulating layer disposed above the substrate; a first lower electrode and a second lower electrode that are disposed above the insulating layer, spaced apart from each other, and lined up in one direction; a rib layer having a first pixel opening overlapping the first lower electrode and a second pixel opening overlapping the second lower electrode; and a lens that is formed in a convex shape protruding to the opposite side to the substrate and that covers at least a part of each of the first pixel opening and the second pixel opening in plan view. Each of the first lower electrode and the second lower electrode includes a first portion and a second portion spaced apart from each other and lined up in the aforementioned direction. The second portion is disposed between the first portion and the center line of the lens in plan view.

Description

Display device

[0001] An embodiment of the present invention relates to a display device.

[0002] In recent display devices, there is a demand for varying the viewing angle at which a predetermined contrast ratio can be obtained. For example, in a display device mounted on a vehicle such as an automobile, viewing angle control is required such that a displayed image is visible from the passenger seat side, while the displayed image is not visible from the driver seat side when the driver is driving.

[0003] Japanese Patent Application Laid-Open No. 2000-195677, Japanese Patent Application Laid-Open No. 2004-207217, Japanese Patent Application Laid-Open No. 2008-135325, Japanese Patent Application Laid-Open No. 2009-32673, Japanese Patent Application Laid-Open No. 2010-118191, International Publication No. WO 2018 / 179308, United States Patent Application Publication No. 2022 / 0077251

[0004] One object of the present invention is to provide a display device capable of controlling a viewing angle.

[0005] A display device according to an embodiment comprises: a substrate; an insulating layer disposed above the substrate; a first lower electrode and a second lower electrode disposed above the insulating layer, spaced apart from each other, and aligned in one direction; a rib layer having a first pixel opening overlapping the first lower electrode and a second pixel opening overlapping the second lower electrode; a first organic layer in contact with the first lower electrode through the first pixel opening and configured to emit light of a first color; a second organic layer in contact with the second lower electrode through the second pixel opening and configured to emit light of a second color different from the first color; an upper electrode covering the first organic layer and the second organic layer; and a lens disposed above the upper electrode, formed in a convex shape protruding toward the opposite side of the substrate, and covering at least a part of each of the first pixel opening and the second pixel opening in a plan view, wherein each of the first lower electrode and the second lower electrode has a first portion and a second portion that are spaced apart from each other and aligned in said direction, and the second portion is disposed between the first portion and a center line of the lens in a plan view.

[0006] Figure 1 is a diagram showing an example configuration of the display device according to this embodiment. Figure 2 is a circuit diagram showing an example of the circuit configuration of a subpixel. Figure 3 is a schematic plan view showing an example of the layout of a subpixel. Figure 4 is a schematic cross-sectional view of the display device along the line IV-IV in Figure 3. Figure 5 is a schematic plan view showing an example of the layout of a subpixel of the display device according to this embodiment. Figure 6 is a schematic cross-sectional view of the display device along the line VI-VI in Figure 5. Figure 7 is a diagram for explaining the function of the lens. Figure 8 is a diagram for explaining the effect of the display device according to this embodiment. Figure 9 is a diagram showing the display device when an image is displayed in the first mode. Figure 10 is a diagram showing the display device when an image is displayed in the second mode. Figure 11 is a diagram showing the display device when an image is displayed in the third mode. Figure 12 is a schematic plan view showing an example of the layout of a subpixel and lens. Figure 13 is a schematic plan view showing another example of the layout of a subpixel and lens. Figure 14 is a schematic plan view showing yet another example of the layout of a subpixel and lens. Figure 15 is a schematic cross-sectional view of the display device along the XVa-XVa and XVb-XVb lines in Figure 14.

[0007] Several embodiments will be described with reference to the drawings. The disclosure is merely an example, and any modifications that a person skilled in the art could easily conceive while maintaining the spirit of the invention are naturally included within the scope of the present invention. Furthermore, the drawings may schematically represent the width, thickness, shape, etc., of each part compared to the actual embodiment in order to clarify the explanation, but these are merely examples and do not limit the interpretation of the present invention. In addition, in this specification and in each drawing, components that perform the same or similar functions as those described above with respect to previously shown drawings are denoted by the same reference numerals, and redundant detailed explanations may be omitted as appropriate.

[0008] Furthermore, the drawings will include mutually orthogonal X, Y, and Z axes as needed to facilitate understanding. The direction along the X-axis will be called the X-direction (first direction), the direction along the Y-axis will be called the Y-direction (second direction), and the direction along the Z-axis will be called the Z-direction. Viewing various elements parallel to the Z-direction is called a plan view.

[0009] Each embodiment of the display device is an organic electroluminescent display device equipped with an organic light-emitting diode (OLED) as a display element, and can be mounted on various electronic devices such as televisions, personal computers, in-vehicle equipment, tablet terminals, smartphones, mobile phone terminals, and wearable terminals.

[0010] Figure 1 shows an example of the configuration of a display device DSP according to this embodiment. The display device DSP includes an insulating substrate 10. The substrate 10 has a display area DA for displaying an image and a peripheral area SA around the display area DA. The substrate 10 may be glass or a flexible resin film.

[0011] In this embodiment, the shape of the substrate 10 in plan view is a rectangle that is elongated in the X direction. However, the shape of the substrate 10 in plan view is not limited to a rectangle, and may be other shapes such as a square, circle, or ellipse.

[0012] The display area DA comprises a plurality of pixels PX arranged in a matrix in the X and Y directions. Each pixel PX includes a plurality of sub-pixels SP that display different colors. In this embodiment, it is assumed that the pixel PX includes a sub-pixel SP1 that is green (first color), a sub-pixel SP2 that is blue (second color), and a sub-pixel SP3 that is red. However, the pixel PX may include sub-pixels SP of other colors, such as white, together with sub-pixels SP1, SP2, and SP3, or in place of any one of sub-pixels SP1, SP2, and SP3.

[0013] The peripheral area SA, although not described in detail here, is provided with terminals for connecting IC chips and flexible printed circuit boards.

[0014] Figure 2 is a circuit diagram showing an example of the circuit configuration of a sub-pixel SP. The sub-pixel SP comprises a pixel circuit 1 and display elements DEa and DEb driven by the pixel circuit 1. The pixel circuit 1 comprises a pixel switch 2, a drive transistor 3, a capacitor 4, and switching elements SW1 and SW2. The pixel switch 2, the drive transistor 3, and the switching elements SW1 and SW2 are composed of, for example, thin-film transistors.

[0015] The display area DA is arranged with multiple scan lines GL that supply scan signals to the pixel circuit 1 of each sub-pixel SP, multiple signal lines SL that supply video signals to the pixel circuit 1 of each sub-pixel SP, and multiple power lines PL. In the example in Figure 2, the scan lines GL and power lines PL extend in the X direction, and the signal lines SL extend in the Y direction.

[0016] The gate electrode of the pixel switch 2 is connected to the scan line GL. One of the source and drain electrodes of the pixel switch 2 is connected to the signal line SL, and the other is connected to the gate electrode of the drive transistor 3 and the capacitor 4. One of the source and drain electrodes of the drive transistor 3 is connected to the power line PL and the capacitor 4, and the other is connected to the display element DEa via the switching element SW1. Furthermore, the other is also connected to the display element DEb via the switching element SW2. In other words, the drive transistor 3 is connected in series with the display elements DEa and DEb, respectively.

[0017] One of the source and drain electrodes of switching element SW1 is connected to the drive transistor 3 and switching element SW2, and the other is connected to the anode of display element DEa. One of the source and drain electrodes of switching element SW2 is connected to the drive transistor 3 and switching element SW1, and the other is connected to the anode of display element DEb. In other words, switching element SW1 (first switching element) is positioned between the drive transistor 3 and display element DEa (first display element), and switching element SW2 (second switching element) is positioned between the drive transistor 3 and display element DEb (second display element). Display elements DEa and DEb are connected in parallel. The gate electrode of switching element SW1 is connected to the switch wiring SWL1. The gate electrode of switching element SW2 is connected to the switch wiring SWL2.

[0018] Note that the configuration of the pixel circuit 1 is not limited to the example shown. For example, the pixel circuit 1 may include more thin-film transistors and capacitors.

[0019] The display elements DEa and DEb are organic light-emitting diodes (OLEDs) as light-emitting elements, and are sometimes referred to as organic EL elements.

[0020] The display device DSP has a first mode, a second mode, and a third mode, which are switched by signals supplied to the switch wiring SWL1 and SWL2, respectively. The first mode is a mode in which switching element SW1 is ON and switching element SW2 is OFF. The second mode is a mode in which both switching elements SW1 and SW2 are ON. The third mode is a mode in which switching element SW1 is OFF and switching element SW2 is ON.

[0021] When the display device DSP is in the first mode, switching element SW1 conducts between the drive transistor 3 and the anode of display element DEa. Switching element SW2 does not conduct between the drive transistor 3 and the anode of display element DEb. Therefore, in the first mode, display element DEa emits light, but display element DEb does not.

[0022] When the display device DSP is in the second mode, switching element SW1 conducts between the drive transistor 3 and the display element DEa. Switching element SW2 conducts between the drive transistor 3 and the display element DEb. Therefore, in the second mode, both display elements DEa and DEb emit light.

[0023] When the display device DSP is in the third mode, the switching element SW1 does not conduct electricity between the drive transistor 3 and the anode of the display element DEa. However, the switching element SW2 conducts electricity between the drive transistor 3 and the anode of the display element DEb. Therefore, in the third mode, the display element DEa does not emit light, but the display element DEb does.

[0024] In this way, by switching between the first mode, the second mode, and the third mode, the illumination state of the display elements DEa and DEb can be switched.

[0025] Figure 3 is a schematic plan view showing an example of the layout of sub-pixels SP1, SP2, and SP3. In the example in Figure 3, sub-pixels SP2 and SP3 are aligned with sub-pixel SP1 in the X direction. Furthermore, sub-pixels SP2 and SP3 are aligned in the Y direction.

[0026] A rib layer 5 is arranged in the display area DA. The rib layer 5 has pixel apertures AP1, AP2, and AP3 in the sub-pixels SP1, SP2, and SP3, respectively. Note that the size and shape of the pixel apertures AP1, AP2, and AP3 are not limited to the example shown.

[0027] The sub-pixel SP1 comprises lower electrodes LE11 and LE12 (first lower electrodes), an upper electrode UE1 (first upper electrode), and an organic layer OR1 (first organic layer), which overlap with the pixel aperture AP1 (first pixel aperture), respectively. The lower electrodes LE11 and LE12 are spaced apart from each other and aligned in the X direction. The upper electrode UE1 and the organic layer OR1 continuously overlap with the lower electrodes LE11 and LE12. The peripheral edges of the organic layer OR1 and the upper electrode UE1 overlap with the rib layer 5 in a plan view. The organic layer OR1 includes, for example, a light-emitting layer that emits light in the green wavelength range. The pixel aperture AP1 has a portion that overlaps with the lower electrode LE11 and a portion that overlaps with the lower electrode LE12. These portions are spaced apart from each other. The rib layer 5 extends in the Y direction in the region between the lower electrodes LE11 and LE12.

[0028] The sub-pixel SP2 comprises lower electrodes LE21 and LE22 (second lower electrodes), an upper electrode UE2 (second upper electrode), and an organic layer OR2 (second organic layer), which overlap with the pixel aperture AP2 (second pixel aperture), respectively. The lower electrodes LE21 and LE22 are spaced apart from each other and aligned in the X direction. The upper electrode UE2 and the organic layer OR2 continuously overlap with the lower electrodes LE21 and LE22. The peripheral edges of the organic layer OR2 and the upper electrode UE2 overlap with the rib layer 5 in a plan view. The organic layer OR2 includes, for example, a light-emitting layer that emits light in the blue wavelength range. The pixel aperture AP2 has a portion that overlaps with the lower electrode LE21 and a portion that overlaps with the lower electrode LE22. These portions are spaced apart from each other. The rib layer 5 extends in the Y direction in the region between the lower electrodes LE21 and LE22.

[0029] The sub-pixel SP3 comprises lower electrodes LE31 and LE32, an upper electrode UE3, and an organic layer OR3, which overlap with the pixel aperture AP3, respectively. The lower electrodes LE31 and LE32 are spaced apart from each other and aligned in the X direction. The upper electrode UE3 and the organic layer OR3 continuously overlap with the lower electrodes LE31 and LE32. The peripheral edges of the organic layer OR3 and the upper electrode UE3 overlap with the rib layer 5 in a plan view. The organic layer OR3 includes, for example, a light-emitting layer that emits light in the red wavelength range. The pixel aperture AP3 has a portion that overlaps with the lower electrode LE31 and a portion that overlaps with the lower electrode LE32. These portions are spaced apart from each other. The rib layer 5 extends in the Y direction in the region between the lower electrodes LE31 and LE32.

[0030] In the example shown in Figure 3, the lower electrodes LE12 and LE22 are positioned between the lower electrodes LE11 and LE21 in the X direction. Also, the lower electrodes LE12 and LE32 are positioned between the lower electrodes LE11 and LE31 in the X direction.

[0031] The organic layer OR1 has a first region AR11, which corresponds to the region where the pixel aperture AP1 and the lower electrode LE11 (first portion) overlap in a plan view, and a second region AR12, which corresponds to the region where the pixel aperture AP1 and the lower electrode LE12 (second portion) overlap in a plan view. The first region AR11 and the second region AR12 are spaced apart from each other and aligned in the X direction.

[0032] The organic layer OR2 has a first region AR21 corresponding to the region where the pixel aperture AP2 and the lower electrode LE21 overlap in a plan view, and a second region AR22 corresponding to the region where the pixel aperture AP2 and the lower electrode LE22 overlap in a plan view. The first region AR21 and the second region AR22 are spaced apart from each other and aligned in the X direction.

[0033] The organic layer OR3 has a first region AR31 corresponding to the region where the pixel aperture AP3 and the lower electrode LE31 overlap in a plan view, and a second region AR32 corresponding to the region where the pixel aperture AP3 and the lower electrode LE32 overlap in a plan view. The first region AR31 and the second region AR32 are spaced apart from each other and aligned in the X direction.

[0034] In the example in Figure 3, the outlines of the lower electrodes LE11, LE12, LE21, LE22, LE31, and LE32 are shown by dotted lines, and the outlines of the organic layers OR1, OR2, OR3 and the upper electrodes UE1, UE2, and UE3 are shown by dashed lines. The first regions AR11, AR21, AR31 and the second regions AR12, AR22, AR32 are shown by hatched lines. Note that the outlines of the lower electrodes, organic layers, upper electrodes, first regions, and second regions shown in the figure do not necessarily reflect their exact shapes.

[0035] Sub-pixels SP1, SP2, and SP3 each have display elements DE1, DE2, and DE3, respectively. Display elements DE1, DE2, and DE3 have light-emitting layers formed from materials that emit light of different colors.

[0036] The display element DE1 includes display elements DE1a and DE1b. Display element DE1a is composed of the lower electrode LE11, the upper electrode UE1, and the portion of the organic layer OR1 that overlaps with the first region AR11. Display element DE1b is composed of the lower electrode LE12, the upper electrode UE1, and the portion of the organic layer OR1 that overlaps with the second region AR12.

[0037] The display element DE2 includes display elements DE2a and DE2b. Display element DE2a is composed of the lower electrode LE21, the upper electrode UE2, and the portion of the organic layer OR2 that overlaps with the first region AR21. Display element DE2b is composed of the lower electrode LE22, the upper electrode UE2, and the portion of the organic layer OR2 that overlaps with the second region AR22.

[0038] The display element DE3 includes display elements DE3a and DE3b. Display element DE3a is composed of the lower electrode LE31, the upper electrode UE3, and the portion of the organic layer OR3 that overlaps with the first region AR31. Display element DE3b is composed of the lower electrode LE32, the upper electrode UE3, and the portion of the organic layer OR3 that overlaps with the second region AR32.

[0039] Display elements DE1a, DE2a, and DE3a correspond to display element DEa shown in Figure 2. Display elements DE1b, DE2b, and DE3b correspond to display element DEb shown in Figure 2.

[0040] When the display device DSP is in the first mode, as described above, the display element DEa shown in Figure 2 emits light, but the display element DEb does not. Therefore, in the first mode, the first regions AR11, AR21, and AR31 emit light, but the second regions AR12, AR22, and AR32 do not emit light.

[0041] When the display device DSP is in the second mode, the display elements DEa and DEb shown in Figure 2 emit light as described above. Therefore, in the second mode, the first regions AR11, AR21, AR31 and the second regions AR12, AR22, AR32 emit light.

[0042] When the display device DSP is in the third mode, as described above, the display element DEa shown in Figure 2 does not emit light, but the display element DEb does. Therefore, in the third mode, the first regions AR11, AR21, and AR31 do not emit light, but the second regions AR12, AR22, and AR32 do emit light.

[0043] A conductive partition wall 6 is positioned in the display area DA. The partition wall 6 is located above the rib layer 5 and overlaps with the rib layer 5 overall. In the example in Figure 3, the partition wall 6 has openings in the sub-pixels SP1, SP2, and SP3, respectively. From another viewpoint, the partition wall 6 is grid-like in plan view and surrounds the display elements DE1, DE2, and DE3, respectively. However, the partition wall 6 does not overlap with the portion of the rib layer 5 located between the lower electrodes LE11 and LE12, the portion located between the lower electrodes LE21 and LE22, and the portion located between the lower electrodes LE31 and LE32. The partition wall 6 serves as wiring that supplies a common voltage to the upper electrodes UE1, UE2, and UE3.

[0044] In one example, the lower electrode LE11 corresponds to the anode of display element DE1a, the lower electrode LE21 corresponds to the anode of display element DE2a, and the lower electrode LE31 corresponds to the anode of display element DE3a. Also, the lower electrode LE12 corresponds to the anode of display element DE1b, the lower electrode LE22 corresponds to the anode of display element DE2b, and the lower electrode LE32 corresponds to the anode of display element DE3b. The upper electrodes UE1, UE2, and UE3 correspond to the cathodes of display elements DE1a, DE1b, DE2a, DE2b, DE3a, and DE3b.

[0045] Fig. 4 is a schematic cross-sectional view of the display device DSP taken along line IV-IV in Fig. 3. A circuit layer 11 is disposed on the aforementioned substrate 10. The circuit layer 11 includes various circuits and wires such as the pixel circuit 1, scanning lines GL, signal lines SL, and power supply lines PL shown in Fig. 2. The circuit layer 11 is covered by an organic insulating layer 12. The organic insulating layer 12 functions as a planarization film that planarizes unevenness generated by the circuit layer 11.

[0046] Lower electrodes LE11, LE12, LE21, LE22, LE31, LE32 are disposed on the organic insulating layer 12 and spaced apart from each other. A rib layer 5 is disposed on the organic insulating layer 12 and the lower electrodes LE11, LE12, LE21, LE22, LE31, LE32. Ends of the lower electrodes LE11, LE12, LE21, LE22, LE31, LE32 are covered by the rib layer 5. Although not shown in the cross-section of Fig. 4, the lower electrodes LE11, LE12, LE21, LE22, LE31, LE32 are each connected to the pixel circuit 1 (the drain electrode of the driving transistor 3 shown in Fig. 2) of the circuit layer 11 through a contact hole provided in the organic insulating layer 12.

[0047] The partition wall 6 includes a conductive lower portion 61 disposed on the rib layer 5, and an upper portion 62 disposed on the lower portion 61. The upper portion 62 has a larger width than the lower portion 61. Accordingly, both end portions of the upper portion 62 protrude beyond the side surfaces of the lower portion 61. Such a shape of the partition wall 6 is called an overhang shape.

[0048] In the example of Fig. 4, the lower portion 61 has a bottom layer 63 disposed on the rib layer 5, and a shaft layer 64 disposed on the bottom layer 63. For example, the bottom layer 63 is formed thinner than the shaft layer 64. In the example of Fig. 4, both end portions of the bottom layer 63 protrude from the side surface of the shaft layer 64. Further, an end portion of the bottom layer 63 is located between an end portion of the upper portion 62 and a side surface of the shaft layer 64 in a plan view. The upper portion 62 is disposed on the shaft layer 64.

[0049] Organic layer OR1 covers the lower electrodes LE11 and LE12 through the pixel aperture AP1. Upper electrode UE1 covers organic layer OR1 and faces the lower electrodes LE11 and LE12. Organic layer OR2 covers the lower electrodes LE21 and LE22 through the pixel aperture AP2. Upper electrode UE2 covers organic layer OR2 and faces the lower electrodes LE21 and LE22. Organic layer OR3 covers the lower electrodes LE31 and LE32 through the pixel aperture AP3. Upper electrode UE3 covers organic layer OR3 and faces the lower electrodes LE31 and LE32. Upper electrodes UE1, UE2, and UE3 are in contact with the side surface of the lower part 61 of the partition wall 6.

[0050] Display element DE1 includes a cap layer CP1 covering the upper electrode UE1. Display element DE2 includes a cap layer CP2 covering the upper electrode UE2. Display element DE3 includes a cap layer CP3 covering the upper electrode UE3. The cap layers CP1, CP2, and CP3 each serve as optical adjustment layers that improve the efficiency of light extraction from the organic layers OR1, OR2, and OR3, respectively.

[0051] In the following description, a multilayer including an organic layer OR1, an upper electrode UE1, and a cap layer CP1 will be referred to as multilayer film FL1, a multilayer including an organic layer OR2, an upper electrode UE2, and a cap layer CP2 will be referred to as multilayer film FL2, and a multilayer including an organic layer OR3, an upper electrode UE3, and a cap layer CP3 will be referred to as multilayer film FL3.

[0052] Sub-pixels SP1, SP2, and SP3 are each fitted with sealing layers SE11, SE12, and SE13 (first sealing layers) that cover the laminated films FL1, FL2, and FL3, respectively. Sealing layer SE11 is placed on top of cap layer CP1 and continuously covers the display element DE1 and the surrounding partition wall 6. Sealing layer SE12 is placed on top of cap layer CP2 and continuously covers the display element DE2 and the surrounding partition wall 6. Sealing layer SE13 is placed on top of cap layer CP3 and continuously covers the display element DE3 and the surrounding partition wall 6.

[0053] In the example shown in Figure 4, the sealing layer SE11 on the partition wall 6 between sub-pixels SP1 and SP2 is separated from the sealing layer SE12 on the same partition wall 6. Also, the sealing layer SE11 on the partition wall 6 between sub-pixels SP1 and SP3 is separated from the sealing layer SE13 on the same partition wall 6. However, any two of the sealing layers SE11, SE12, and SE13 may be in contact above the partition wall 6.

[0054] For example, gaps are formed between the sealing layers SE11, SE12, SE13 and the upper part 62 of the partition wall 6. The laminated films FL1, FL2, FL3 may be placed in at least a portion of these gaps.

[0055] The sealing layers SE11, SE12, and SE13 are covered by a resin layer RS1 (first resin layer). Resin layer RS1 is covered by a sealing layer SE2 (second sealing layer). Sealing layer SE2 is covered by a resin layer RS2 (second resin layer). Resin layers RS1, RS2, and sealing layer SE2 are provided continuously over at least the entire display area DA, with a portion extending into the peripheral area SA. In Figure 4, elements above resin layer RS2 are omitted.

[0056] The organic insulating layer 12 is formed of an organic insulating material such as polyimide. The rib layer 5 and the sealing layers SE11, SE12, SE13, SE2 are formed of an inorganic insulating material such as silicon nitride (SiNx), silicon oxide (SiOx), or silicon oxynitride (SiON). In one example, the rib layer 5 is formed of silicon oxynitride, and the sealing layers SE11, SE12, SE13, SE2 are formed of silicon nitride. The resin layers RS1, RS2 are formed of a resin material (organic insulating material) such as epoxy resin or acrylic resin.

[0057] The lower electrodes LE11, LE12, LE21, LE22, LE31, and LE32 each have a reflective layer and a pair of conductive oxide layers covering the upper and lower surfaces of the reflective layer, respectively. The reflective layer can be formed from a metallic material with excellent light reflectivity, such as silver. Each conductive oxide layer can be formed from a transparent conductive oxide such as ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), or IGZO (Indium Gallium Zinc Oxide). The upper electrodes UE1, UE2, and UE3 are formed from a metallic material such as a magnesium-silver alloy (MgAg).

[0058] The organic layers OR1, OR2, and OR3 are composed of multiple thin films including an emissive layer. In one example, the organic layers OR1, OR2, and OR3 have a structure in which a hole injection layer, a hole transport layer, an electron blocking layer, an emissive layer, a hole blocking layer, an electron transport layer, and an electron injection layer are stacked in the Z direction in sequence. However, the organic layers OR1, OR2, and OR3 may have other structures, such as a so-called tandem structure including multiple emissive layers.

[0059] The cap layers CP1, CP2, and CP3 have a laminated structure in which, for example, multiple transparent layers are stacked on top of each other. These transparent layers may include layers formed from inorganic materials and layers formed from organic materials. Furthermore, these transparent layers have different refractive indices. For example, the refractive indices of these transparent layers are different from those of the upper electrodes UE1, UE2, and UE3 and the sealing layers SE11, SE12, and SE13. Note that at least one of the cap layers CP1, CP2, and CP3 may be omitted.

[0060] The bottom layer 63 and axial layer 64 of the partition wall 6 are formed of, for example, a metallic material. Examples of metallic materials for the bottom layer 63 include molybdenum (Mo), titanium (Ti), titanium nitride (TiN), molybdenum-tungsten alloy (MoW), or molybdenum-niobium alloy (MoNb). Examples of metallic materials for the axial layer 64 include aluminum (Al), aluminum-neodymium alloy (AlNd), aluminum-yttrium alloy (AlY), or aluminum-silicon alloy (AlSi). At least one of the bottom layer 63 and the axial layer 64 may have a laminated structure of multiple layers. Furthermore, the axial layer 64 may include a layer formed of an insulating material.

[0061] For example, the upper part 62 of the partition wall 6 has a laminated structure consisting of a lower layer made of a metallic material and an upper layer made of a conductive oxide. As the metallic material forming the lower layer, for example, titanium, titanium nitride, molybdenum, tungsten, molybdenum-tungsten alloy, or molybdenum-niobium alloy can be used. As the conductive oxide forming the upper layer, for example, ITO or IZO can be used. The upper part 62 may also have a single-layer structure of metallic material. Furthermore, the upper part 62 may include a layer made of an insulating material.

[0062] A common voltage is supplied to the partition wall 6. This common voltage is supplied to the upper electrodes UE1, UE2, and UE3, which are in contact with the side surface of the lower part 61. The lower electrodes LE11, LE12, LE21, LE22, LE31, and LE32 are supplied with pixel voltages corresponding to the video signal on the signal line SL through the pixel circuits 1 of the sub-pixels SP1, SP2, and SP3, respectively.

[0063] The organic layers OR1, OR2, and OR3 emit light in response to the application of voltage. Specifically, when a potential difference is formed between the lower electrode LE11 and the upper electrode UE1, the portion of the light-emitting layer of organic layer OR1 that overlaps with the first region AR11 emits light in the green wavelength range. When a potential difference is formed between the lower electrode LE12 and the upper electrode UE1, the portion of the light-emitting layer of organic layer OR1 that overlaps with the second region AR12 emits light in the green wavelength range.

[0064] Similarly, when a potential difference is formed between the lower electrode LE21 and the upper electrode UE2, the portion of the light-emitting layer of the organic layer OR2 that overlaps with the first region AR21 emits light in the blue wavelength range. When a potential difference is formed between the lower electrode LE22 and the upper electrode UE2, the portion of the light-emitting layer of the organic layer OR2 that overlaps with the second region AR22 emits light in the blue wavelength range.

[0065] Similarly, when a potential difference is formed between the lower electrode LE31 and the upper electrode UE3, the portion of the light-emitting layer of the organic layer OR3 that overlaps with the first region AR31 emits light in the red wavelength range. When a potential difference is formed between the lower electrode LE32 and the upper electrode UE3, the portion of the light-emitting layer of the organic layer OR3 that overlaps with the second region AR32 emits light in the red wavelength range.

[0066] The display device DSP may include a layer containing quantum dots that are excited by light emitted from the light-emitting layer to generate light of a color corresponding to the sub-pixels SP1, SP2, and SP3.

[0067] The display device DSP does not necessarily have a partition wall 6. In this case, the upper electrodes UE1, UE2, and UE3 are formed integrally, for example, and continuously cover the organic layers OR1, OR2, and OR3.

[0068] Figure 5 is a schematic plan view showing an example of the layout of sub-pixels SP1, SP2, and SP3 of the display device DSP according to this embodiment. In the example shown in Figure 5, sub-pixels SP1, SP2, and SP3 are arranged in this order in the Y direction. Also, sub-pixels SP1 and SP2 are arranged alternately in the X direction, and sub-pixels SP1 and SP3 are arranged alternately in the X direction.

[0069] The display device DSP further includes multiple lenses ML1 arranged in the X direction. The lenses ML1 extend in the Y direction and overlap with multiple sub-pixels SP1, SP2, SP3 (display elements DE1, DE2, DE3). In the example shown in Figure 5, the lenses ML1 overlap with rows of sub-pixels SP1, SP2, SP3 arranged in the Y direction and adjacent rows of sub-pixels SP1, SP2, SP3.

[0070] In the example shown in Figure 5, lens ML1 completely covers each of the pixel apertures AP1, AP2, and AP3 in a plan view. However, lens ML1 does not necessarily have to completely cover each of the pixel apertures AP1, AP2, and AP3 in a plan view. Lens ML1 is a cylindrical lens formed from a transparent resin material such as epoxy resin, acrylic resin, or polyimide resin.

[0071] Lens ML1 has a center line MC1. In the example shown in Figure 5, the center line MC1 is parallel to the Y direction. The center line MC1 is also located between adjacent sub-pixels SP1 and SP2 in the X direction, and between adjacent sub-pixels SP1 and SP3 in the X direction.

[0072] In this specification, the center line MC1 of lens ML1 is a line connecting multiple principal points of lens ML1. A principal point is a point where the principal surface of lens ML1 and the optical axis intersect perpendicularly. The principal surface is a plane perpendicular to the optical axis that includes the intersection point of the light ray before incidence and the light ray after emission when a light ray parallel to the optical axis is incident on lens ML1. Directions X1 and X2 shown in Figure 5 will be described later.

[0073] Figure 6 is a schematic cross-sectional view of the display device DSP along the VI-VI line in Figure 5. As shown in the enlarged view in Figure 6, the portion of the rib layer 5 located between the lower electrodes LE11 and LE12 is in contact with the organic insulating layer 12. The portion of the rib layer 5 located between the lower electrodes LE21 and LE22 is in contact with the organic insulating layer 12. The portion of the rib layer 5 located between the lower electrodes LE31 and LE32 is in contact with the organic insulating layer 12. No partition wall 6 is placed above these portions of the rib layer 5. These portions are covered by organic layers OR1, OR2, and OR3, respectively.

[0074] The display device DSP includes a light-shielding layer BM placed on top of the resin layer RS2. The light-shielding layer BM is covered by a plurality of lenses ML1. In the example shown in Figure 6, the edges of the light-shielding layer BM are covered by adjacent lenses ML1 in the X direction. That is, the light-shielding layer BM overlaps with the peripheral edges of the lenses ML1 in a plan view. In the illustrated example, a portion of the upper surface of the light-shielding layer BM is exposed from adjacent lenses ML1 in the X direction, but the upper surface of the light-shielding layer BM may be completely covered by adjacent lenses ML1 in the X direction. The light-shielding layer BM overlaps with the rib layer 5 and the partition wall 6 in a plan view. The light-shielding layer BM is made of, for example, a resin material with high light absorption.

[0075] The lens ML1 is positioned on the resin layer RS2. The lens ML1 is formed in a convex shape. In the example shown in Figure 6, the lens ML1 protrudes on the side opposite to the substrate 10. The lens ML1 has a symmetrical shape with respect to an axis parallel to the Y direction. Therefore, the focal point of the lens ML1 is located on the center line MC1 of the lens ML1.

[0076] The center line MC1 of lens ML1 overlaps with the rib layer 5 and the partition wall 6. The top portion MT of lens ML1 also overlaps with the center line MC1 and, in a plan view, overlaps with the rib layer 5 and the partition wall 6. Lens ML1 is in contact with, for example, an air layer. In other examples, lens ML1 may be covered with a layer formed of a material having a refractive index smaller than that of lens ML1.

[0077] Lower electrode LE12 is located between lower electrode LE11 and center line MC1 in a plan view. Lower electrode LE22 is located between lower electrode LE21 and center line MC1 in a plan view. Lower electrode LE32 is located between lower electrode LE31 and center line MC1 in a plan view.

[0078] The display device DSP may include color filters corresponding to the colors of the light-emitting layers contained in each of the organic layers OR1, OR2, and OR3. Furthermore, the display device DSP may include an organic insulating layer for adjusting the focal position of the lens ML1.

[0079] Figure 7 is a diagram illustrating the function of lens ML1. In the example shown in Figure 7(a), the light-emitting unit P1 is positioned on the center line MC1 of lens ML1. In this case, light emitted from the light-emitting unit P1 toward lens ML1 is refracted or travels in a straight line by lens ML1 and propagates in the forward direction (Z direction). Therefore, when the light-emitting unit P1 is positioned close to the center line MC1 of lens ML1, the light emitted from the light-emitting unit P1 can be seen from the front of the display device DSP, but it is almost invisible from oblique positions (left and right positions in Figure 7(a)).

[0080] In the example shown in Figure 7(b), the light-emitting unit P1 is positioned slightly away from the center line MC1 of the lens ML1 in the X direction. In this case, the light emitted from the light-emitting unit P1 toward the lens ML1 is refracted or travels in a straight line by the lens ML1 and propagates in an oblique direction (a direction tilted in the X direction relative to the Z direction). Therefore, when the light-emitting unit P1 is positioned away from the center line MC1 of the lens ML1 in the X direction, the light emitted from the light-emitting unit P1 is almost invisible from the front of the display device DSP, but it is visible from an oblique position (the position on the right in Figure 7(b)).

[0081] In the example shown in Figure 7(c), the light-emitting unit P1 is positioned further in the X direction from the center line MC1 of the lens ML1 than in Figure 7(b). In this case, the light emitted from the light-emitting unit P1 toward the lens ML1 travels in a direction that is more inclined in the X direction with respect to the Z direction than in Figure 7(b).

[0082] Thus, as the light-emitting unit P1 moves away from the center line MC1 of the lens ML1 in the X direction, the angle between the direction in which the light passing through the lens ML1 propagates and the Z direction increases. Therefore, by changing the position of the light-emitting unit P1, it becomes possible to control the position in which the screen displayed on the display device DSP can be viewed.

[0083] Next, the effects of the display device DSP according to this embodiment will be explained using Figure 8. Figure 8 is a diagram for explaining the effects of the display device DSP according to this embodiment. Hereinafter, the direction toward the right of the display device DSP along the X direction (the direction pointed to by the arrow in the X direction) will be defined as direction X1, and the direction toward the left of the display device DSP along the X direction will be defined as direction X2.

[0084] Display element DEb is positioned near the center line MC1 of lens ML1. Display element DEa is positioned further away from the center line MC1 of lens ML1 in the X direction than display element DEb. Therefore, the light ray L1 emitted from display element DEa travels diagonally after passing through lens ML1. On the other hand, the light ray L2 emitted from display element DEb travels straight ahead after passing through lens ML1. Therefore, when the display device DSP is viewed from the front, the user can barely see the light emitted from display element DEa, but can see the light emitted from display element DEb. Also, when the display device DSP is viewed from an angle, the user can see the light emitted from display element DEa, but can barely see the light emitted from display element DEb. In the example shown in Figure 8, the light emitted from display element DE1a can be seen from a position on the X1 side of the center line MC1, and the light emitted from display element DE2a can be seen from a position on the X2 side of the center line MC1. In this way, by dividing the display element DE into display elements DEa and DEb, and changing the lighting state of each of the display elements DEa and DEb, it is possible to control the viewing angle of the display device DSP.

[0085] Furthermore, in this embodiment, the lower electrodes LE11, LE12, LE21, LE22, and LE31, LE32 are spaced apart. Therefore, charge leakage between the lower electrodes LE11, LE12, between the lower electrodes LE21, LE22, and between the lower electrodes LE31, LE32 can be prevented. This prevents unintended illumination of the display elements and suppresses a decrease in the display quality of the display device DSP.

[0086] Next, we will describe the case where the DSP display device of this embodiment is installed in a vehicle such as an automobile. Figures 9 to 11 show the DSP display device of this embodiment installed in an in-vehicle device. In a DSP display device installed in a vehicle such as an automobile, it is required that different images be visible on the driver's side and the passenger's side while the vehicle is in motion, and that the image be invisible from the driver's side. On the other hand, it is required that the same image be visible on the driver's side and the passenger's side when the engine is off.

[0087] Figure 9 shows the DSP display device when displaying an image in the first mode. In the example shown in Figure 9, the DSP display device is mounted between the driver's seat and the passenger seat. The driver's seat is located towards direction X2 from the DSP display device, and the passenger seat is located towards direction X1 from the DSP display device.

[0088] The following describes the case where the arrangement of the display elements DE1, DE2, DE3 and lens ML1 is as shown in the example in Figure 4. The passenger PAS in the front passenger seat can see the light emitted from the display elements DE1, DE2, DE3 that are on the X2 direction from the center line MC1 among the display elements DE1, DE2, DE3 that overlap with lens ML1. The driver DRV sitting in the driver's seat can see the light emitted from the display elements DE1, DE2, DE3 that are on the X1 direction from the center line MC1 among the display elements DE1, DE2, DE3 that overlap with lens ML1.

[0089] In the first mode, the display elements DE1a, DE2a, and DE3a emit light. The passenger in the front seat (PAS) can see the light emitted from the display elements DE1a, DE2a, and DE3a that overlap the lens ML1 and are located on the X2 side from the center line MC1. The driver (DRV) sitting in the driver's seat can see the light emitted from the display elements DE1a, DE2a, and DE3a that overlap the lens ML1 and are located on the X1 side from the center line MC1.

[0090] Here, the display elements DE1a, DE2a, and DE3a on the X2 side of the center line MC1 are supplied with image signals to display an image for the passenger PAS in the front passenger seat. The display elements DE1, DE2, and DE3 on the X1 side of the center line MC1 are supplied with image signals to display an image for the driver DRV. As a result, the passenger PAS in the front passenger seat and the driver DRV can view screens 101 and 102, each displaying a different image. The first mode is applied, for example, when the vehicle is in motion.

[0091] Figure 10 shows the DSP display device when displaying an image in the second mode. In the example shown in Figure 10, the DSP display device is mounted in front of the passenger seat.

[0092] In the second mode, the display elements DE1a, DE1b, DE2a, DE2b, DE3a, and DE3b emit light. The passenger in the front seat (PAS) can see the light emitted from the display elements DE1b, DE2b, and DE3b. The driver (DRV) sitting in the driver's seat can see the light emitted from the display elements DE1a, DE2a, and DE3a that overlap the lens ML1, specifically those on the X1 side of the center line MC1.

[0093] Here, a common image signal is supplied to the display elements DE1a, DE1b, DE2a, DE2b, DE3a, and DE3b. As a result, the passenger PAS in the front seat and the driver DRV can view screens 101 and 102, respectively, displaying the same image. The second mode is applied, for example, when the vehicle's engine is off.

[0094] Figure 11 shows the DSP display device when displaying an image in the third mode. In the example shown in Figure 11, the DSP display device is mounted in front of the passenger seat.

[0095] In the third mode, the display elements DE1b, DE2b, and DE3b emit light. The passenger in the front seat (PAS) can see the light emitted from the display elements DE1b, DE2b, and DE3b. The driver (DRV) sitting in the driver's seat can barely see the light emitted from the display elements DE1b, DE2b, and DE3b.

[0096] Here, the display elements DE1b, DE2b, and DE3b are supplied with image signals for displaying an image for the passenger PAS in the front passenger seat. As a result, the passenger PAS in the front passenger seat can view the screen 101 with the image displayed. The driver DRV can view a dark screen 102 where the image is barely visible. The third mode is applied, for example, when the vehicle is in motion.

[0097] Figures 12 to 14 are schematic plan views showing an example of the layout of sub-pixels SP1, SP2, SP3 and lens ML1.

[0098] In the example shown in Figure 12, a first column is formed in which sub-pixels SP1 are aligned in the Y direction, and a second column is formed in which sub-pixels SP2 and SP3 are aligned alternately in the Y direction. In the display area DA, two columns of the first column are aligned in the X direction, and two columns of the second column are aligned in the X direction, which are arranged alternately in the X direction. Lens ML1 extends in the Y direction and overlaps the first and second columns. The center line MC1 is located between adjacent sub-pixels SP1 and SP2 in the X direction, and between adjacent sub-pixels SP1 and SP3 in the X direction.

[0099] The same effects as described above can be obtained with the display device DSP shown in Figure 12.

[0100] In the example shown in Figure 13, rows of sub-pixels SP1 aligned in the Y direction and rows of sub-pixels SP2 and SP3 aligned alternately in the Y direction are arranged alternately in the X direction. Lens ML1 overlaps with one set of sub-pixels SP1, SP2, and SP3.

[0101] In the display area DA, a third and fourth column are formed, each consisting of multiple lenses ML1 arranged in the X direction. The third and fourth columns are arranged alternately in the Y direction. The lenses ML1 of the third column overlap with sub-pixels SP1 on the X2 direction side of the center line MC1, and with sub-pixels SP2 and SP3 on the X1 direction side of the center line MC1. The lenses ML1 of the fourth column overlap with sub-pixels SP2 and SP3 on the X2 direction side of the center line MC1, and with sub-pixel SP1 on the X1 direction side of the center line MC1.

[0102] The same effects as described above can be obtained with the DSP display device shown in Figure 13.

[0103] In the example shown in Figure 14, the sub-pixels SP1, SP2, SP3 and lens ML1 are arranged in the same way as in the example shown in Figure 13. The corners of lens ML1 are rounded. Lens ML1 may also be formed in a circular or elliptical shape when viewed from above.

[0104] In the example shown in Figure 14, a portion of each of the display elements DE1, DE2, and DE3 is not covered by the lens ML1. The portions of the display elements DE1, DE2, and DE3 that are not covered by the lens ML1 are covered by, for example, a light-shielding layer BM (not shown). Alternatively, the display elements DE1, DE2, and DE3 may be completely covered by the lens ML1.

[0105] Figure 15 is a schematic cross-sectional view of the display device DSP along the XVa-XVa line and the XVb-XVb line in Figure 14. The upper part of Figure 15 is a cross-sectional view of the display device DSP along the XVa-XVa line. The cross-sectional shape of the lens ML1 along the X direction is convex, protruding on the opposite side from the substrate 10.

[0106] The diagram shown at the bottom of Figure 15 is a cross-sectional view of the display device DSP along the XVb-XVb line. The cross-sectional shape of the lens ML1 along the Y direction is convex, protruding away from the substrate 10. Therefore, the viewing angle in the Y direction is limited. By limiting the viewing angle in the Y direction, for example, when the display device DSP is mounted in a car, it is possible to suppress reflections of the displayed image on the car's windshield.

[0107] The same effects as described above can be obtained with the display device DSP shown in Figures 14 and 15.

[0108] All display devices that a person skilled in the art can implement by appropriately modifying the design based on the display devices described above as embodiments of the present invention also fall within the scope of the present invention insofar as they encompass the gist of the present invention.

[0109] Within the scope of the concept of the present invention, a person skilled in the art can conceive of various modifications, and such modifications are also understood to fall within the scope of the present invention. For example, modifications to the above-described embodiments in which a person skilled in the art has appropriately added, deleted, or modified components, or added, omitted, or modified processes, are also included within the scope of the present invention, as long as they retain the gist of the present invention.

[0110] Furthermore, any other effects and advantages brought about by the embodiments described above that are obvious from the description herein or that can be appropriately conceived by those skilled in the art are naturally considered to be brought about by the present invention.

[0111] DSP...Display device, DE1a, DE1b, DE2a, DE2b, DE3a, DE3b...Display elements, LE11, LE12, LE21, LE22, LE31, LE32...Lower electrodes, OR1, OR2, OR3...Organic layers, UE1, UE2, UE3...Upper electrodes, SE11, SE12, SE13, SE2...Sealing layers, 5...Rib layer, 6,...Partition wall, 61...Lower part, 62...Upper part, 63...Bottom layer, 64...Axial layer, ML1...Lens, BM...Light-shielding layer.

Claims

1. A display device comprising: a substrate; an insulating layer disposed above the substrate; a first lower electrode and a second lower electrode disposed above the insulating layer, spaced apart from each other and aligned in one direction; a rib layer having a first pixel aperture overlapping the first lower electrode and a second pixel aperture overlapping the second lower electrode; a first organic layer in contact with the first lower electrode through the first pixel aperture and configured to emit light in a first color; a second organic layer in contact with the second lower electrode through the second pixel aperture and configured to emit light in a second color different from the first color; an upper electrode covering the first organic layer and the second organic layer; and a lens disposed above the upper electrode, formed in a convex shape protruding away from the substrate, and covering at least a portion of each of the first and second pixel apertures in a plan view, wherein each of the first and second lower electrodes has a first portion and a second portion spaced apart from each other and aligned in the direction, and the second portion is positioned between the first portion and the center line of the lens in a plan view.

2. The display device according to claim 1, wherein each of the first organic layer and the second organic layer has a first region in contact with the first portion and a second region in contact with the second portion, and comprises a first mode in which only the first region emits light, a second mode in which both the first and second regions emit light, and a third mode in which only the second region emits light.

3. The display device according to claim 2, further comprising: a drive transistor; a first display element connected in series with the drive transistor and including the first portion; a second display element connected in series with the drive transistor and in parallel with the first display element and including the second portion; a first switching element disposed between the drive transistor and the first display element; and a second switching element disposed between the drive transistor and the second display element, wherein the first switching element is configured to conduct between the drive transistor and the first display element in the first and second modes, and not conduct between the drive transistor and the first display element in the third mode; and the second switching element is configured not to conduct between the drive transistor and the second display element in the first mode, and to conduct between the drive transistor and the second display element in the second and third modes.

4. The display device according to claim 1, wherein the second portion of the first lower electrode and the second lower electrode are located between the first portion of the first lower electrode and the first portion of the second lower electrode in a plan view.

5. The display device according to claim 1, wherein the first lower electrode and the second lower electrode are aligned in a first direction, and the lens is a cylindrical lens extending in a second direction intersecting the first direction.

6. The display device according to claim 1, wherein the first lower electrode and the second lower electrode are aligned in a first direction, and the cross-sectional shape of the lens along the first direction and the second direction intersecting the first direction is convex, projecting toward the side opposite to the substrate.

7. The display device according to claim 1, wherein the rib layer is disposed between the first portion and the second portion of the first lower electrode and between the first portion and the second portion of the second lower electrode.

8. The display device according to claim 7, wherein the first lower electrode and the second lower electrode are arranged on the insulating layer, the rib layer is in contact with the insulating layer between the first portion and the second portion of the first lower electrode, and the rib layer is in contact with the insulating layer between the first portion and the second portion of the second lower electrode.

9. The display device according to claim 1, wherein the top of the lens overlaps with the rib layer in a plan view.

10. The display device according to claim 1, further comprising a light-shielding layer that overlaps with the periphery of the lens in a plan view.

11. The display device according to claim 10, wherein the light-shielding layer overlaps with the rib layer in a plan view.

12. The display device according to claim 1, wherein the lens completely covers the first pixel aperture and the second pixel aperture in a plan view.

13. The display device according to claim 1, further comprising a partition wall including a conductive lower portion disposed on the rib layer and an upper portion disposed on the lower portion and protruding from the side surface of the lower portion, wherein the upper electrode includes a first upper electrode that covers the first organic layer and is in contact with the lower portion and a second upper electrode that covers the second organic layer and is in contact with the lower portion.

14. The display device according to claim 13, wherein the top of the lens overlaps with the partition wall in a plan view.

15. The display device according to claim 13, further comprising a light-shielding layer that overlaps with the periphery of the lens and the partition wall in a plan view.

16. The display device according to claim 1, further comprising: a cap layer covering the upper electrode; a first sealing layer made of an inorganic material covering the cap layer; a first resin layer made of an organic material covering the first sealing layer; a second sealing layer made of an inorganic material covering the first resin layer; and a second resin layer made of an organic material covering the second sealing layer, wherein the lens is positioned above the second resin layer.

17. The display device according to claim 16, wherein the lens is in contact with the second resin layer.

18. The display device according to claim 16 or 17, further comprising a light-shielding layer that overlaps with the periphery of the lens in a plan view and is disposed between the lens and the second resin layer.

Images