Display device

Abstract

The display device (2) comprises a first display panel (10) having a bent first end (10z) and a second display panel (20) having a bent second end (20z), the first display panel and the second display panel being arranged in a plane in a manner such that the first end and the second end are adjacent to each other, sub-pixels (Sq1, Sq2) are respectively arranged on the first end and the second end, and a connecting portion (30) having a light diffusion function is formed between the first end and the second end.

Description

Technical Field

[0001] The present invention relates to a display device. Background Art

[0002] Patent Document 1 discloses a method for improving the uniformity of in-plane light emission by providing a light extraction member so as to overlap with a joint (transparent adhesive layer) between two light emitting panels arranged in a planar manner.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: International Publication "WO2013 / 027508" Summary of the invention

[0006] Problems to be solved by the invention

[0007] In a display device configured by connecting a plurality of display panels arranged in a plane, there is a problem in that display quality is degraded due to the formation of a connection portion (joint).

[0008] Solutions to Solve Problems

[0009] A display device involved in one embodiment of the present invention comprises: a first display panel having a bent first end; and a second display panel having a bent second end, the first display panel and the second display panel are arranged in a plane in a manner such that the first end is adjacent to the second end, sub-pixels are respectively provided at the first end and the second end, and a connecting portion (seam) with a light diffusion function is formed between the first end and the second end.

[0010] Beneficial Effects

[0011] The display quality of a display device formed by connecting a plurality of display panels can be improved.

[0012] BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 (a) is a plan view showing the structure of the present display device, Figure 1 (b) is a cross-sectional view showing the structure of the present display device.

[0014] Figure 2 (a) is a cross-sectional view showing the structure near the connection portion, Figure 2 (b) is a cross-sectional view showing the structure of a sub-pixel.

[0015] Figure 3 It is a schematic diagram showing the image display method in the present display device.

[0016] Figure 4 It is a graph showing the relationship between the viewing angle of a sub-pixel and the front luminance ratio.

[0017] Figure 5 It is a plan view showing the display state of the present display device.

[0018] Figure 6 (a) is a perspective view showing an example of the shape of the light diffusion particle. Figure 6 (b) is a perspective plan view showing the relationship between the shape of the light emitting region of the sub-pixel and the shape of the light diffusion particles.

[0019] Figure 7 It is a cross-sectional view showing another structure of the display device.

[0020] Figure 8 It is a plan view showing a display state of a conventional display device. DETAILED DESCRIPTION

[0021] Figure 1 (a) is a plan view showing the structure of the present display device, Figure 1 (b) is a cross-sectional view showing the structure of the present display device. Figure 2 (a) is a cross-sectional view showing the structure near the connection portion, Figure 2 (b) is a cross-sectional view showing the structure of a sub-pixel.

[0022] like Figure 1 and Figure 2 As shown, the display device 2 includes a first display panel 10 having a bent first end 10z and a second display panel 20 having a bent second end 20z. The first display panel 10 and the second display panel 20 are arranged in a plane in a manner such that the first end 10z and the second end 20z are adjacent to each other, and a connecting portion 30 (a seam between the first display panel 10 and the second display panel 20) having a light diffusion function is formed between the first end 10z and the second end 20z.

[0023] In the display device 2, a light diffusion layer KL having an adhesive function is provided in a manner covering the first display panel 10 and the second display panel 20, and the connecting portion 30 is constituted by a part of the light diffusion layer KL. Figure 2 As shown in (b) , the light diffusion layer KL has a structure in which a plurality of light diffusion particles Kp are dispersed in a thermosetting resin HJ.

[0024] The first display panel 10 and the second display panel 20 each include a flexible substrate 3 , a TFT layer (thin film transistor layer) 4 , a light emitting element layer 5 , and a sealing layer 6 .

[0025] In the light emitting element layer 5, a first electrode 22, an edge cover film 23 covering the edge of the first electrode 22, an active layer 24 including a light emitting layer EL, and a second electrode 25 (common electrode) are formed. The first electrode 22, the second electrode 25 and the active layer 24 constitute a light emitting element Es.

[0026] Regarding the first display panel 10, a plurality of sub-pixels Sp1 are provided at the non-end portion (flat portion) FA, and a plurality of sub-pixels Sq1 are provided at the bent first end portion 10z. Regarding the second display panel 20, a plurality of sub-pixels Sp2 are provided at the non-end portion (flat portion) FA, and a plurality of sub-pixels Sq2 are provided at the bent second end portion 20z. The sub-pixels Sp1, Sq1, Sp2, and Sq2 include a light-emitting element Es formed in the light-emitting element layer 5 and a pixel circuit (not shown) formed in the TFT layer 4.

[0027] The substrate 3 is a flexible base material mainly composed of a glass substrate or a resin such as polyimide, and for example, the substrate 3 may be composed of two layers of polyimide films and an inorganic film sandwiched therebetween. Although not shown in the figure, a primer film (for example, an inorganic insulating film such as silicon nitride) is formed between the substrate 3 and the TFT layer 4 to prevent the intrusion of foreign matter such as water and oxygen.

[0028] A pixel circuit (not shown) connected to the light emitting element Es is formed in the TFT layer 4. The pixel circuit includes a plurality of transistors including a driving transistor and a capacitor, and is connected to a plurality of signal lines such as a scanning signal line, a data signal line, and a light emitting control signal line, and a power supply line.

[0029] In the light emitting element layer 5, one of the first electrode 22 and the second electrode 25 functions as an anode, and the other functions as a cathode. The first electrode 22 is, for example, a light reflecting electrode composed of a laminate of ITO (Indium Tin Oxide) and Ag (silver) or an alloy containing Ag (silver). The second electrode 25 is, for example, composed of a metal thin film such as a magnesium-silver alloy, and has light transmittance. The edge covering film 23 is formed of an organic insulating material such as polyimide. In addition, the overlapping area between the non-edge portion of the first electrode 22 (the exposed portion not covered by the edge covering film 23) and the light emitting layer EL becomes the light emitting area EA.

[0030] The active layer 24 is formed by evaporation, inkjet, coating, photolithography, etc. As the light-emitting layer EL of the active layer 24, an island-shaped organic light-emitting layer, an island-shaped quantum dot light-emitting layer, etc. can be used. In addition to the light-emitting layer EL, the active layer 24 may also include at least one of a hole injection layer, a hole transport layer, an electron blocking layer, a hole blocking layer, an electron transport layer, and an electron injection layer.

[0031] The light-emitting layer EL in the active layer 24 is an organic light-emitting layer. When the light-emitting element Es constitutes an organic light-emitting diode (OLED), holes and electrons are recombined in the light-emitting layer through the driving current between the first electrode 22 and the second electrode 25, and light is emitted in the process of the excitons generated thereby migrating to the base state.

[0032] In addition, the light-emitting layer EL of the active layer 24 is a quantum dot light-emitting layer. When the light-emitting element Es constitutes a quantum dot light-emitting diode (QLED), holes and electrons are recombined in the light-emitting layer through the driving current between the first electrode 22 and the second electrode 25, and the excitons generated thereby emit light in the process of migrating from the conduction band energy level (conduction band) of the quantum dot to the valence band energy level (valence band).

[0033] The sealing layer 6 covering the light emitting element layer 5 is a layer for preventing foreign matter such as water and oxygen from penetrating into the light emitting element layer 5 , and may be composed of, for example, two inorganic sealing films and an organic film formed therebetween.

[0034] Figure 3 2 is a schematic diagram showing an image display method in the present display device. Figure 3 As shown in (a), an image is displayed on the sub-pixels Sp1 and Sq1 of the first display panel 10 (including the first end 10z) and the sub-pixel Sp2 of the non-end of the second display panel 20, and an image is not displayed on the sub-pixel Sq2 of the second end 20z (the light-emitting element Es of the sub-pixel Sq2 is non-luminous) during the first period, as shown in FIG. Figure 3 As shown in (b), an image is displayed on the sub-pixels Sp2 and Sq2 of the second display panel 20 (including the second end 20z) and the sub-pixel Sp1 of the non-end of the first display panel 10, and an image is not displayed on the sub-pixel Sq1 of the first end 10z (the light-emitting element Es of the sub-pixel Sq1 is non-luminous). The first period and the second period can be a certain period, and the first period and the second period are preferably set alternately. For example, the first period can be set as an odd frame period, and the second period can be set as an even frame period.

[0035] Figure 4 It is a graph showing the relationship between the viewing angle of a sub-pixel (the angle between the perpendicular direction of the sub-pixel and the visual recognition direction of the sub-pixel) and the front brightness ratio (the ratio of the brightness when the viewing angle is θ to the brightness when the viewing angle is zero). Figure 5 is a plan view showing the display state of the display device. Figure 4 It is shown that the front luminance ratio at a large viewing angle (30° or more) is greatly improved by providing the light diffusion layer KL on the sub-pixel.

[0036] Thus, by displaying an image on the sub-pixel Sq1 of the first end 10z or the sub-pixel Sq2 of the second end 20z and making the connecting portion 30 between the first end 10z and the second end 20z have a light diffusion function, Figure 5 In this way, when viewed from an oblique angle, it can be seen that the image (a portion of B and C) is displayed on the connecting portion 30. Figure 8 The conventional display (with obvious seams) shown can improve the display quality of the display device 2 formed by connecting the first display panel 10 and the second display panel 20.

[0037] like Figure 4 As shown, the front luminance ratio of the sub-pixel decreases as the viewing angle increases. In the display device 2, the viewing angle of the sub-pixel Sq1 is larger than that of the sub-pixel Sp1. Therefore, even when the same grayscale is input to the sub-pixel Sp1 and the sub-pixel Sq1 in the first period, the luminance of the sub-pixel Sq1 is made larger than the luminance of the sub-pixel Sp1. In the second period, since no image is displayed in the sub-pixel Sq1, the total lighting time of the sub-pixel Sq1 is shorter than that of the sub-pixel Sp1. Therefore, even when the luminance of the sub-pixel Sq1 is made larger than the luminance of the sub-pixel Sp1, the degradation deviation between the sub-pixel Sp1 and the sub-pixel Sq1 can be suppressed.

[0038] Similarly, the viewing angle of the sub-pixel Sq2 is larger than that of the sub-pixel Sp2. Therefore, even when the same grayscale is input to the sub-pixel Sp2 and the sub-pixel Sq2 in the second period, the luminance of the sub-pixel Sq2 is larger than that of the sub-pixel Sp2. In the first period, since no image is displayed in the sub-pixel Sq2, the total lighting time of the sub-pixel Sq2 is shorter than that of the sub-pixel Sp2. Therefore, even when the luminance of the sub-pixel Sq2 is larger than that of the sub-pixel Sp2, the degradation deviation between the sub-pixel Sp2 and the sub-pixel Sq2 can be suppressed.

[0039] Figure 6 (a) is a perspective view showing an example of the shape of light diffusion particles. Figure 6 (b) is a perspective plan view showing the relationship between the shape of the light emitting region of the sub-pixel and the shape of the light diffusion particles.

[0040] like Figure 6 As shown, the maximum diameter Lk of the light diffusion particle Kp is smaller than the minimum diameter Ls of the light emitting area EA of the sub-pixels Sp1 , Sq1 , Sp2 , and Sq2 . Figure 6In (a), the light diffusion particle Kp is formed into a cubic shape, but this is only an example, and it can also be any shape (including a sphere, an ellipsoid, and a polyhedron). In addition, the maximum diameter Lk of the light diffusion particle Kp is the maximum length of the line segment connecting two points on the surface of the light diffusion particle Kp, and the minimum diameter Ls of the light emitting area EA is the minimum length of the line segment connecting two points on the outer edge (edge) of the light emitting area EA. In the case where the maximum diameter Lk of each light diffusion particle Kp is uneven, the average maximum diameter of multiple light diffusion particles Kp and the minimum diameter Ls of the light emitting area EA are compared.

[0041] In this way, by making the maximum diameter Lk of the light diffusion particle Kp smaller than the minimum diameter Ls of the light emitting area EA, it is possible to suppress image blurring.

[0042] Figure 7 is a cross-sectional view showing other structures of the display device. Figure 4 As shown in , the front luminance ratio of the sub-pixel decreases with the increase of viewing angle. Figure 7 As shown, the viewing angle θ (angle formed by the vertical line VL of the screen and the vertical line SL of the first end 10z) when observing the first end 10z (including the plurality of sub-pixels Sq1 arranged in the oblique direction) from the direction of the vertical line VL of the screen is equal to the bending angle of the first end 10z relative to the non-end FA. Similarly, the viewing angle when observing the sub-pixel Sq2 of the second end 20z (including the plurality of sub-pixels Sq2 arranged in the oblique direction) from the direction of the vertical line of the non-end FA is equal to the bending angle of the second end 20z relative to the non-end FA.

[0043] Therefore, in the first display panel 10, the first end portion 10z is bent at a viewing angle with respect to the non-end portion FA and a front luminance ratio of 0.5 or more (at Figure 4 In the second display panel 20, the bending angle of the second end portion 20z relative to the non-end portion FA can also be set to a viewing angle (in Figure 4 , θ is less than 65°).

[0044] The above-mentioned embodiments are for the purpose of illustration and description, and are not intended to be limiting. Based on these illustrations and descriptions, it is obvious to those skilled in the art that many variations are possible.

[0045] 〔Summarize〕

[0046] [Method 1]

[0047] A display device comprising:

[0048] A first display panel having a bent first end portion; and

[0049] The second display panel has a bent second end portion,

[0050] The first display panel and the second display panel are arranged in a plane in such a manner that the first end portion and the second end portion are adjacent to each other.

[0051] Sub-pixels are provided at the first end and the second end, respectively, and a connection portion having a light diffusion function is formed between the first end and the second end.

[0052] [Method 2]

[0053] For example, the display device described in the first embodiment is provided with:

[0054] During a first period, an image is displayed in the sub-pixel at the first end and no image is displayed in the sub-pixel at the second end;

[0055] During a second period, no image is displayed in the sub-pixel at the first end portion, and an image is displayed in the sub-pixel at the second end portion.

[0056] [Method 3]

[0057] For example, the display device described in Method 1 or 2 includes a light diffusion layer covering the first display panel and the second display panel.

[0058] [Method 4]

[0059] For example, in the display device described in the third aspect, the light diffusion layer has an adhesive function, and the connecting portion is composed of a part of the light diffusion layer.

[0060] [Method 5]

[0061] For example, in the display device described in the second embodiment, in the first display panel, when the same grayscale is input to the sub-pixel at the non-end portion and the sub-pixel at the first end portion, the luminance of the sub-pixel at the first end portion is greater than the luminance of the sub-pixel at the non-end portion.

[0062] In the second display panel, when the same grayscale is input to the sub-pixel at the non-end portion and the sub-pixel at the second end portion, the luminance of the sub-pixel at the second end portion is greater than the luminance of the sub-pixel at the non-end portion.

[0063] [Method 6]

[0064] For example, in the display device described in the second embodiment, the first period is an odd-numbered frame period, and the second period is an even-numbered frame period.

[0065] [Method 7]

[0066] For example, in the display device described in the third embodiment, the light diffusion layer includes light diffusion particles and resin.

[0067] [Method 8]

[0068] For example, in the display device described in any one of the embodiments 1 to 7, in the first display panel, the bending angle of the first end portion relative to the non-end portion is equal to a viewing angle at which the front luminance ratio is greater than 0.5,

[0069] In the second display panel, a bending angle of the second end portion relative to the non-end portion is equal to a viewing angle at which the front luminance ratio is greater than or equal to 0.5.

[0070] [Method 9]

[0071] For example, in the display device described in aspect 7, the maximum diameter of the light diffusion particle is smaller than the minimum diameter of the light emitting region of the sub-pixel.

[0072] [Method 10]

[0073] For example, in the display device according to any one of aspects 1 to 9, the sub-pixel includes a light-emitting element including a first electrode, a light-emitting layer, and a second electrode.

[0074] [Method 11]

[0075] For example, in the display device according to any one of aspects 1 to 10, the first display panel and the second display panel are flexible.

[0076] [Method 12]

[0077] For example, in the display device described in embodiment 10, the light-emitting element is an organic light-emitting diode or a quantum dot light-emitting diode.

[0078] Description of Reference Numerals

[0079] 2 Display device

[0080] 3 substrate

[0081] 4 TFT layer (thin film transistor layer)

[0082] 5 Light-emitting element layer

[0083] 6 Sealing layer

[0084] 10 First display panel

[0085] 10z First end

[0086] 20 Second display panel

[0087] 20z Second end

[0088] 22. First electrode

[0089] 23 Edge Covering Film

[0090] 24 Active layer

[0091] 25 Second electrode

[0092] 30 Connection

[0093] FA Non-end

[0094] Es Light Emitting Element

[0095] EL light emitting layer

[0096] Sp1, Sq1, Sp2, Sq2 sub-pixels

[0097] KL Light Diffuser

[0098] HJ Thermosetting Resin

[0099] Kp Light Diffuser Particles

Claims

1. A display device, characterized in that: have: a first display panel having a bent first end portion; and a second display panel having a bent second end portion, The first display panel and the second display panel are arranged in a plane in such a manner that the first end portion and the second end portion are adjacent to each other. Sub-pixels are disposed at the first end and the second end, respectively. A connecting portion having a light diffusion function is formed between the first end portion and the second end portion, The settings are: During a first period, an image is displayed in the sub-pixel at the first end and no image is displayed in the sub-pixel at the second end; During a second period, no image is displayed in the sub-pixel at the first end portion, and an image is displayed in the sub-pixel at the second end portion.

2. The display device according to claim 1, characterized in that A light diffusion layer covering the first display panel and the second display panel is included.

3. The display device according to claim 2, characterized in that: The light diffusion layer has an adhesive function. The connecting portion is constituted by a portion of the light diffusion layer.

4. The display device according to claim 1, characterized in that In the first display panel, when the same grayscale is input to the sub-pixel at the non-end portion and the sub-pixel at the first end portion, the luminance of the sub-pixel at the first end portion is greater than the luminance of the sub-pixel at the non-end portion. In the second display panel, when the same grayscale is input to the sub-pixel at the non-end portion and the sub-pixel at the second end portion, the luminance of the sub-pixel at the second end portion is greater than the luminance of the sub-pixel at the non-end portion.

5. The display device according to claim 1, characterized in that The first period is an odd-numbered frame period, and the second period is an even-numbered frame period.

6. The display device according to claim 2, characterized in that: The light diffusion layer includes light diffusion particles and a resin.

7. The display device according to claim 1, characterized in that: In the first display panel, the bending angle of the first end portion relative to the non-end portion is equal to a viewing angle at which the front luminance ratio is greater than 0.5, In the second display panel, a bending angle of the second end portion relative to the non-end portion is equal to a viewing angle at which the front luminance ratio is greater than or equal to 0.

5.

8. The display device according to claim 6, characterized in that: The maximum diameter of the light diffusion particle is smaller than the minimum diameter of the light emitting region of the sub-pixel.

9. The display device according to claim 1, characterized in that: The sub-pixel includes a light-emitting element including a first electrode, a light-emitting layer, and a second electrode.

10. The display device according to any one of claims 1 to 9, characterized in that: The first display panel and the second display panel are flexible.

11. The display device according to claim 9, characterized in that The light emitting element is an organic light emitting diode or a quantum dot light emitting diode.

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