Wavelength conversion substrate and display device

Abstract

Provided is a technique in which, in a display device provided with a wavelength conversion substrate in which partition walls are provided, a decrease in brightness and a loss in color due to the generation of bubbles in a wavelength conversion layer do not readily occur. A wavelength conversion substrate (3A) is provided with: a transparent substrate (31) having a first main surface and a second main surface; a resin layer (34) provided on the first main surface and having a plurality of first through-holes; an inorganic coating layer (35) including a plurality of first portions that at least partially cover the side walls of the plurality of first through-holes; and wavelength conversion layers (36G, 36R) including a plurality of wavelength conversion parts provided in at least a portion of the plurality of first through-holes, respectively. Here, the coverage rate of the first portion with respect to the side wall is 60% or more, the length (L1) of an opening on the transparent substrate (31) side of each of the plurality of first through holes is in the range of 10-1000 [mu] m, and the ratio (W1 / L1) of the width (W1) of the opening on the transparent substrate (31) side to the length (L1) is in the range of 0.01-0.95.

Description

Technical Field

[0001] The present invention relates to a wavelength conversion substrate and a display device. Background Art

[0002] In a display device, a light-emitting element such as a light-emitting diode is used, for example, as a light source of a backlight unit, or as a component of a pixel or a sub-pixel. In such a display device, a partition wall is sometimes provided to separate the light-emitting element, or the pixel or the sub-pixel from each other. The partition wall can, for example, effectively utilize the light emitted by the light-emitting element, or prevent the light emitted by other light-emitting elements from entering the area where the light emitted by a certain light-emitting element should enter.

[0003] Patent Documents 1 and 2 propose a display device including a wavelength conversion layer including a color conversion phosphor that converts the wavelength of blue light into red light and green light. Such a display device can display a color image even with a monochromatic light source.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2000-131683

[0007] Patent Document 2: Japanese Patent Application Publication No. 2009-244383 Summary of the invention

[0008] Two or more wavelength conversion layers that convert light from a light source into light of different colors can be formed in two or more recesses separated from each other by a partition wall. When a partition wall is provided, for example, a thicker wavelength conversion layer can be formed with higher positional accuracy. Therefore, a higher wavelength conversion efficiency can be achieved, and color mixing can be less likely to occur.

[0009] As a method for forming a wavelength conversion layer in the above-mentioned concave portion, there are a method of using a photosensitive material as a coating liquid and drawing a coating film by photolithography, and a nozzle coating method of selectively supplying the coating liquid to a specific position. In either method, bubbles are easily generated between the inner surface of the concave portion and the coating film, and in the coating film. The bubbles generated in the wavelength conversion layer may cause problems such as reduced brightness and color loss in the display device.

[0010] An object of the present invention is to provide a technology for preventing a decrease in brightness and a loss in color due to the generation of bubbles in a wavelength conversion layer in a display device including a wavelength conversion substrate provided with partition walls.

[0011] According to one aspect of the present invention, there is provided a wavelength conversion substrate, comprising: a transparent substrate having a first main surface and a second main surface; a resin layer, disposed on the first main surface, having a plurality of first through holes; an inorganic covering layer, comprising a plurality of first portions, each at least partially covering the side walls of the plurality of first through holes; and a wavelength conversion layer, comprising a plurality of wavelength conversion portions, each disposed in at least a portion of the plurality of first through holes, wherein the coverage of the first portion on the side wall is 60% or more,

[0012] For each of the plurality of first through holes, a length L1 of the opening on the transparent substrate side is within a range of 10 to 1000 μm, and a ratio W1 / L1 of a width W1 of the opening on the transparent substrate side to the length L1 is within a range of 0.01 to 0.95.

[0013] According to other aspects of the present invention, a wavelength conversion substrate as described in the above aspects is provided, wherein the inorganic covering layer also includes a plurality of second parts, and the plurality of second parts respectively extend at the positions of the openings of the plurality of first through holes on the transparent substrate side and respectively have second through holes whose sizes are smaller than the openings.

[0014] According to further aspects of the present invention, a wavelength conversion substrate according to any one of the above aspects is provided, wherein the ratio W1 / L1 is in the range of 0.01 to 0.75, and the ratio L2 / L1 of the size L2 of the second through hole in the length direction of the plurality of first through holes to the length L1 is in the range of 0.01 to 0.80.

[0015] According to further aspects of the present invention, there is provided a wavelength conversion substrate as described in any one of the above aspects, wherein the inorganic covering layer further includes a third portion that at least partially covers the upper surface of the resin layer and is adjacent to the first portion.

[0016] According to still another aspect of the present invention, there is provided a wavelength conversion substrate as described in any one of the above aspects, wherein the coverage of the upper surface by the third portion is greater than 80%.

[0017] According to still another aspect of the present invention, there is provided a wavelength conversion substrate as described in any one of the above aspects, wherein the depth of each of the plurality of first through holes is in the range of 10 to 40 μm.

[0018] According to still another aspect of the present invention, there is provided a wavelength conversion substrate as described in any one of the above aspects, wherein the inorganic covering layer is composed of a metal or an alloy.

[0019] According to further aspects of the present invention, there is provided a wavelength conversion substrate as described in any one of the above aspects, further comprising a black matrix, which is sandwiched between the transparent substrate and the resin layer and has a plurality of third through holes at the positions of the plurality of first through holes.

[0020] According to further aspects of the present invention, a wavelength conversion substrate according to any one of the above aspects is provided, wherein the ratio W1 / L1 is in the range of 0.01 to 0.75, and the ratio L3 / L1 of the size L3 of the third through hole in the length direction of the plurality of first through holes to the length L1 is in the range of 0.01 to 0.80.

[0021] According to still another aspect of the present invention, there is provided the wavelength conversion substrate according to any one of the above aspects, further comprising a color filter including a plurality of colored layers respectively arranged at positions of at least a portion of the plurality of third through holes.

[0022] According to still another aspect of the present invention, there is provided a display device comprising: the wavelength conversion substrate according to any one of the above aspects; and a dimming device disposed so as to face the first main surface.

[0023] According to still another aspect of the present invention, there is provided a display device according to any one of the above aspects, wherein the dimming device comprises a substrate, and a plurality of light emitting diodes arranged on the substrate corresponding to the plurality of first through holes.

[0024] According to the present invention, there is provided a technique for preventing a decrease in brightness and a loss in color from occurring due to the generation of bubbles in a wavelength conversion layer in a display device including a wavelength conversion substrate provided with partition walls. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a plan view showing a part of the display device according to the first embodiment of the present invention.

[0026] Figure 2 yes Figure 1 The equivalent circuit diagram of the display device shown.

[0027] Figure 3 It is along Figure 1 A cross-sectional view of the display device taken along line III-III is shown.

[0028] Figure 4 It is along Figure 1 A cross-sectional view of the display device taken along line IV-IV is shown.

[0029] Figure 5 It is along Figure 1A cross-sectional view of the display device taken along line VV is shown.

[0030] Figure 6 It is along Figure 1 A cross-sectional view of the display device taken along line VI-VI is shown.

[0031] Figure 7 Yes means Figure 1 The display device includes a top view of a portion of a black matrix substrate.

[0032] Figure 8 It means from Figure 7 A top view of the structure in which part of the components are omitted in the wavelength conversion substrate.

[0033] Fig. 9 It is a cross-sectional view showing a part of a display device according to a second embodiment of the present invention.

[0034] Fig.10 This is a cross-sectional view showing a part of a display device according to a third embodiment of the present invention.

[0035] Fig.11 It is a cross-sectional view showing a part of a display device according to a fourth embodiment of the present invention.

[0036] Fig.12 is a cross-sectional view showing a part of a display device according to a comparative example.

[0037] Fig.13 It is a cross-sectional view showing a part of a display device according to another comparative example.

[0038] Fig.14 This is a schematic diagram showing bubbles generated in the coating film when coating is performed on the surface of a structure before forming a wavelength conversion layer in Example 1.

[0039] Fig.15 This is a schematic diagram showing bubbles generated in the coating film when coating is performed on the surface of a structure before forming a wavelength conversion layer in Example 2.

[0040] Fig.16 This is a schematic diagram showing a state in which bubbles are not generated in the coating film when coating is performed on the surface of a structure before forming a wavelength conversion layer in Example 3.

[0041] Fig.17 This is a schematic diagram showing bubbles generated in the coating film when coating is performed on the surface of a structure before forming a wavelength conversion layer in Example 4.

[0042] Fig.18 This is a schematic diagram showing bubbles generated in the coating film when coating is performed on the surface of a structure before forming a wavelength conversion layer in Example 5.

[0043] Fig.19 This is a schematic diagram showing bubbles generated in the coating film when coating is performed on the surface of a structure before forming a wavelength conversion layer in Comparative Example 1.

[0044] Fig. 20 This is a schematic diagram showing bubbles generated in the coating film when coating is performed on the surface of a structure before forming a wavelength conversion layer in Comparative Example 2.

[0045] Fig.21 This is a schematic diagram showing bubbles generated in the coating film when coating is performed on the surface of a structure before forming a wavelength conversion layer in Comparative Example 3. DETAILED DESCRIPTION

[0046] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The embodiments described below are obtained by further specifying any one of the above aspects. The matters described below can be incorporated into each of the above aspects individually or in combination of a plurality.

[0047] In addition, the embodiments shown below are examples of structures for embodying the technical concept of the present invention, and the technical concept of the present invention is not limited by the material, shape and structure of the following components. Various changes can be made to the technical concept of the present invention within the technical scope specified by the claims described in the claims.

[0048] In addition, for elements having the same or similar functions, the same reference numerals are given in the following referenced figures, and repeated descriptions are omitted. In addition, the drawings are schematic, and the relationship between the dimensions in a certain direction and the dimensions in other directions and the relationship between the dimensions of a certain component and the dimensions of other components may be different from the actual.

[0049] <1> First Embodiment

[0050] Figure 1 It is a plan view showing a part of the display device according to the first embodiment of the present invention. Figure 2 yes Figure 1 The equivalent circuit diagram of the display device shown. Figure 3 It is along Figure 1 A cross-sectional view of the display device taken along line III-III is shown. Figure 4 It is along Figure 1 A cross-sectional view of the display device taken along line IV-IV is shown. Figure 5 It is along Figure 1 A cross-sectional view of the display device taken along line VV is shown. Figure 6 It is along Figure 1 A cross-sectional view of the display device taken along line VI-VI is shown. Figure 7 Yes means Figure 1 A display device includes a top view of a portion of a wavelength conversion substrate. Figure 1In FIG. 1 , the region surrounded by the dotted line indicates the opening of the third through hole of the black matrix 32 on the transparent substrate 31 side as described later.

[0051] Figures 1 to 6 The display device 1A shown is capable of color display based on an active matrix driving method, and is a micro LED display in which each sub-pixel includes a light emitting diode (LED).

[0052] In each figure, the X direction and the Y direction are directions parallel to the display surface of the display device 1A and intersecting each other. According to one example, the X direction and the Y direction are perpendicular to each other. In addition, the Z direction is a direction perpendicular to the X direction and the Y direction. That is, the Z direction is the thickness direction of the display device 1A.

[0053] like Figure 2 As shown, the display device 1A includes a video signal line VSL, a power line PSL, a scanning signal line SSL, a pixel PX, a video signal line driver VDR, and a scanning signal line driver SDR.

[0054] The video signal lines VSL and the power supply lines PSL extend in the Y direction and are alternately arranged in the X direction. The scanning signal lines SSL extend in the X direction and are alternately arranged in the Y direction.

[0055] The pixels PX are arranged along the X direction and the Y direction. Each pixel PX includes a first sub-pixel PXR, a second sub-pixel PXG, and a third sub-pixel PXB. The first sub-pixel PXR, the second sub-pixel PXG, and the third sub-pixel PXB are arranged corresponding to the intersection of the video signal line VSL and the scanning signal line SSL.

[0056] The first sub-pixel PXR, the second sub-pixel PXG, and the third sub-pixel PXB emit light of different colors. Here, as an example, the first sub-pixel PXR, the second sub-pixel PXG, and the third sub-pixel PXB emit red light, green light, and blue light, respectively.

[0057] In each pixel PX, the first sub-pixel PXR, the second sub-pixel PXG, and the third sub-pixel PXB are arranged in this order along the X direction. The arrangement order of the first sub-pixel PXR, the second sub-pixel PXG, and the third sub-pixel PXB in each pixel PX can be changed.

[0058] In addition, the first sub-pixel PXR, the second sub-pixel PXG, and the third sub-pixel PXB are arranged in stripes here, but the first sub-pixel PXR, the second sub-pixel PXG, and the third sub-pixel PXB may be arranged in other arrangements such as delta arrangement and mosaic arrangement.

[0059] The first sub-pixel PXR, the second sub-pixel PXG, and the third sub-pixel PXB include a light emitting element D, a driving control element DR, a switch SW, and a capacitor C, respectively.

[0060] The light emitting element D is a light emitting diode. The light emitting diode is, for example, a light emitting diode made of an inorganic substance. The light emitting diode made of an inorganic substance is obtained, for example, by monolithicizing a laminate having the same layer structure as them into a plurality of parts. The light emitting element D may also be an electroluminescent element as a light emitting diode made of an organic substance. The cathode of the light emitting element D is connected to the ground electrode. Here, as an example, it is assumed that the light emitting element D is made of an inorganic substance and is a blue light emitting diode that emits blue light.

[0061] The drive control element DR and the switch SW are field effect transistors. Here, the drive control element DR is a p-channel thin film transistor, and the switch SW is an n-channel thin film transistor. The drive control element DR is configured such that the gate is connected to the drain of the switch SW, the source is connected to the power supply line PSL, and the drain is connected to the anode of the light emitting element D. The switch SW is configured such that the gate is connected to the scanning signal line SSL, and the source is connected to the video signal line VSL.

[0062] The capacitor C is, for example, a thin film capacitor and is configured such that one electrode of the capacitor C is connected to the gate of the drive control element DR and the other electrode of the capacitor C is connected to the power supply line PSL.

[0063] The first sub-pixel PXR also includes Figures 3 to 6 The first wavelength conversion layer 36R is shown.

[0064] The first wavelength conversion layer 36R is provided so as to face the light emitting element D of the first sub-pixel PXR. The first wavelength conversion layer 36R converts the light emitted by the light emitting element D of the first sub-pixel PXR into the first light of a specific color. For example, the first wavelength conversion layer 36R converts the blue light emitted by the light emitting element D of the first sub-pixel PXR into red light.

[0065] The second sub-pixel PXG also includes Figure 3 The second wavelength conversion layer 36G is shown.

[0066] The second wavelength conversion layer 36G is provided so as to face the light emitting element D of the second sub-pixel PXG. The second wavelength conversion layer 36G converts the light emitted by the light emitting element D of the second sub-pixel PXG into a second light of a color different from the first light. For example, the second wavelength conversion layer 36G converts the blue light emitted by the light emitting element D of the second sub-pixel PXG into green light.

[0067] The third sub-pixel PXB also includes Figure 3 and Figure 4 Filling layer 36B is shown.

[0068] The filling layer 36B is provided so as to face the light emitting element D of the third sub-pixel PXB. The filling layer 36B is, for example, a colorless and transparent layer. The filling layer 36B can be omitted.

[0069] Image signal line driver VDR and scan signal line driver SDR Figure 2 As shown, the image signal line driver VDR and the scanning signal line driver SDR may be mounted on the display panel by COG (chip on glass) technology. Instead of COG mounting, the image signal line driver VDR and the scanning signal line driver SDR may be mounted by TCP (tape carrier package).

[0070] The video signal line driver VDR is connected to the video signal line VSL and the power supply line PSL, and outputs a voltage signal as a video signal to the video signal line VSL.

[0071] The scanning signal line driver SDR is connected to the scanning signal line SSL. The scanning signal line driver SDR outputs a voltage signal as a scanning signal to the scanning signal line SSL. The power line PSL may be connected to the scanning signal line driver SDR instead of being connected to the video signal line driver VDR.

[0072] The display device 1A will be described in more detail.

[0073] like Figures 3 to 6 As shown, the display device 1A includes a dimming substrate 2 , a wavelength conversion substrate 3A and an adhesive layer 4 .

[0074] The light-adjusting substrate is a substrate that emits light toward the wavelength conversion substrate and is capable of adjusting at least one of the intensity of the light and the time of emitting the light for each pixel or each sub-pixel. Figures 3 to 6 The dimming substrate 2 shown includes a substrate 21 , a semiconductor layer 22 , conductor layers 23A, 23B, 23C and 23D, insulating layers 24A, 24B and 24C, a light emitting element 25 , a partition layer 26 , a filling layer 27 and a conductor layer 28 .

[0075] The substrate 21 includes, for example, an insulating substrate such as a glass substrate. The substrate 21 may also include a primer layer provided on the main surface of the insulating substrate facing the wavelength conversion substrate 3A. The primer layer is, for example, a laminate of a silicon nitride layer and a silicon oxide layer sequentially laminated on the insulating substrate. The substrate 21 may also be a semiconductor substrate such as a silicon substrate. The substrate 21 may be either hard or flexible.

[0076] The semiconductor layer 22 is arranged on the main surface of the substrate 21 facing the wavelength conversion substrate 3A. The semiconductor layer 22 is, for example, a polysilicon layer. The semiconductor layer 22 is a semiconductor layer constituting a thin film transistor of the drive control element DR or the switch SW. Each semiconductor layer 22 includes a source and a drain and a channel region sandwiched therebetween.

[0077] The conductor layer 23A is a conductor pattern provided on the main surface of the substrate 21. The conductor layer 23A constitutes the video signal line VSL, the power line PSL, the source electrode SE, the drain electrode DE, and the lower electrode (not shown) of the capacitor C. The source electrode SE and the drain electrode DE are connected to the source and the drain of the semiconductor layer 22, respectively. The conductor layer 23A is made of metal or alloy. The conductor layer 23A may have a single-layer structure or a multi-layer structure.

[0078] The insulating layer 24A covers the conductor layer 23A and the main surface of the substrate 21. The insulating layer 24A can be formed using TEOS (tetraethyl orthosilicate), for example. The gate insulating film of each thin film transistor constituting the drive control element DR or the switch SW is a part of the insulating layer 24A. In addition, the dielectric layer of each capacitor C is another part of the insulating layer 24A.

[0079] The conductor layer 23B is a conductor pattern provided on the insulating layer 24A. The gate electrode GE of each thin film transistor constituting the drive control element DR or the switch SW is a part of the conductor layer 23B. Each gate electrode GE faces the channel region of the semiconductor layer 22 with the insulating layer 24A in between. In addition, the upper electrode (not shown) of each capacitor C is another part of the conductor layer 23B. Each upper electrode faces the lower electrode of the capacitor C including the upper electrode with the insulating layer 24A in between. The conductor layer 23B is made of metal or alloy. The conductor layer 23B can have a single-layer structure or a multi-layer structure.

[0080] The insulating layer 24B covers the conductive layer 23B and the insulating layer 24A. The insulating layer 24B is an interlayer insulating film. The insulating layer 24B is made of, for example, an inorganic insulator such as silicon oxide. The insulating layer made of an inorganic insulator can be formed by, for example, a plasma CVD (chemical vapor deposition) method.

[0081] like Figure 5 and Figure 6 As shown, the conductor layer 23C is a conductor pattern provided on the insulating layer 24B. The conductor layer 23C constitutes the scanning signal line SSL. The source electrode SE and the drain electrode DE may be provided on the insulating layer 24B instead of being provided on the insulating layer 24A. That is, the scanning signal line SSL and the source electrode SE and the drain electrode DE may also be constituted by the conductor layer 23C.

[0082] The insulating layer 24C covers the conductive layer 23C and the insulating layer 24B. The insulating layer 24C is a passivation film and is made of an inorganic insulator such as silicon nitride.

[0083] The conductor layer 23D is a conductor pattern provided on the insulating layer 24C. The conductor layer 23D constitutes electrode pads arranged in the X direction and the Y direction corresponding to the first sub-pixel PXR, the second sub-pixel PXG, and the third sub-pixel PXB. A through hole is provided at the position of the drain electrode DE connected to the drain of the drive control element DR on the laminate composed of the insulating layers 24A, 24B, and 24C. Each electrode pad is connected to the drain electrode DE via the through hole. The conductor layer 23D is composed of, for example, a metal or an alloy. The conductor layer 23D may have a single-layer structure or a multi-layer structure.

[0084] The contour of the orthographic projection of each electrode pad onto a plane perpendicular to the Z direction is separated from the orthographic projection of the light emitting element 25 disposed on the electrode pad onto the above-mentioned plane and surrounds the orthographic projection. That is, the electrode pad is larger in size in the direction perpendicular to the Z direction than the light emitting element 25. Therefore, the electrode pad also acts as a reflective layer that reflects the light traveling toward the substrate 21. The electrode pad may not play the role of the reflective layer. In this case, the reflective layer that plays this role may be provided separately from the electrode pad or may not be provided.

[0085] Figures 3 to 5 The light emitting element 25 shown is Figure 2 The light emitting element D shown. The light emitting element 25 is arranged on the electrode pad.

[0086] The light emitting element 25 is a light emitting diode made of an inorganic substance. In addition, a substrate including a light emitting diode as the light emitting element 25 is sometimes referred to as an "LED substrate".

[0087] The light emitting element 25 has a multilayer structure including a plurality of layers, for example, a first layer 251, a second layer 252, and a third layer 253. Here, the stacking direction of the layers included in the light emitting element 25 is the Z direction. The stacking direction may be perpendicular to the Z direction.

[0088] Each light emitting element 25 includes an anode and a cathode. The light emitting element 25 has an anode and a cathode on one surface. The anode of the light emitting element 25 is connected to the electrode pad via a bonding wire (not shown). In the case where the light emitting element 25 has an anode on one surface and a cathode on the other surface, the light emitting element 25 can be bonded to the electrode pad and the anode can be connected to the electrode pad by bare chip bonding using a conductive material such as a conductive paste as a bonding material. In the case where the light emitting element 25 has an anode and a cathode on one surface, the conductor layer 28 can be omitted, and an electrode pad for connecting to the cathode of the light emitting element 25 can be further provided on the insulating layer 24C, and wiring connected to these electrode pads can be further provided between the insulating layers, and the light emitting element 25 can be bonded to the electrode pad and the conductor layer 28, and the anode and cathode can be connected to the electrode pad by flip chip bonding.

[0089] The dimensions of the light emitting element 25 in the X and Y directions are preferably in the range of 1 to 100 μm, more preferably in the range of 5 to 80 μm, and further preferably in the range of 10 to 60 μm. The dimension of the light emitting element 25 in the Z direction is preferably in the range of 1 to 20 μm, more preferably in the range of 1 to 15 μm, and further preferably in the range of 1 to 10 μm.

[0090] The partition layer 26 is disposed on the insulating layer 24C. The partition layer 26 has through holes at the positions of the electrode pads. The light-emitting elements 25 are respectively located in these through holes. The partition layer 26 is made of, for example, resin. Such a partition layer 26 can be formed by photolithography using a photosensitive resin. The partition layer 26 can also include a resin layer having through holes, and a reflective layer covering the side walls of these through holes and the upper surface of any resin layer. The reflective layer can have a single-layer structure or a multi-layer structure. The layers included in the reflective layer are, for example, metals, alloys, or transparent dielectrics. The partition layer 26 can be omitted.

[0091] The filling layer 27 fills the gap between the light emitting element 25 and the partition layer 26. The filling layer 27 is a light-transmitting layer that transmits the light emitted by the light emitting element 25. In addition, the filling layer 27 also functions as a protective layer for protecting the light emitting element 25 and the joint between the light emitting element 25 and the electrode. The filling layer 27 is composed of, for example, a resin. The refractive index of the filling layer 27 is preferably different from the refractive index of the material constituting the surface of the partition layer 26.

[0092] The conductor layer 28 is provided on the partition layer 26 and the filling layer 27. The cathode of the light emitting element 25 is connected to the conductor layer 28. When the conductor layer 28 is composed of a conductive transparent oxide, it can be provided so as to cover the entire cathode of the light emitting element 25. When the conductor layer 28 is composed of a metal or an alloy, it is preferably provided so as to cover part of the cathode of the light emitting element 25.

[0093] The wavelength conversion substrate 3A faces the light control substrate 2. Specifically, the wavelength conversion substrate 3A and the substrate 21 face each other with the light emitting element 25 and the like interposed therebetween.

[0094] The wavelength conversion substrate 3A includes a transparent substrate 31 , a black matrix 32 , an overcoat layer 33OC, a resin layer 34 , an inorganic cover layer 35 , a first wavelength conversion layer 36R, a second wavelength conversion layer 36G, and a filling layer 36B.

[0095] The transparent substrate 31 has visible light transmittance. The transparent substrate 31 is, for example, a colorless substrate. The transparent substrate 31 may have a single-layer structure or a multi-layer structure. The transparent substrate 31 is, for example, made of glass, a transparent resin, or a combination thereof. The transparent substrate 31 may be hard or flexible. The transparent substrate 31 has a first main surface facing the dimming substrate 2 and a second main surface as the back surface thereof.

[0096] The black matrix 32 is disposed on the first main surface of the transparent substrate 31. The black matrix 32 is a black layer that blocks visible light. The black matrix 32 is composed of, for example, a mixture containing a binder resin and a colorant. The colorant is, for example, a black pigment, or a mixture of pigments that appear black by subtractive color mixing, such as a mixture containing a blue pigment, a green pigment, and a red pigment.

[0097] The black matrix 32 has third through holes at the positions of the light emitting elements 25. The opening of each third through hole on the transparent substrate 31 side has a larger dimension in the direction perpendicular to the Z direction than the light emitting element 25.

[0098] Here, the opening of the third through hole on the transparent substrate 31 side is as shown in Figure 1 As indicated by the dotted line in the figure, it has a shape extending in the Y direction. The portions corresponding to the pixels PX in the black matrix 32 include a third through hole arranged at the position of the first sub-pixel PXR, a third through hole arranged at the position of the second sub-pixel PXG, and a third through hole arranged at the position of the third sub-pixel PXB, and these three third through holes are arranged in the X direction. A plurality of third through hole groups respectively composed of these three third through holes are arranged in the X direction and the Y direction. The distance between the third through hole groups adjacent in the X direction is greater than the distance between the third through holes included in the same through hole group. The distance between the third through hole groups adjacent in the Y direction is also greater than the distance between the third through holes included in the same through hole group.

[0099] The aperture ratio of the black matrix 32 is preferably in the range of 5 to 66%, more preferably in the range of 5 to 40%, and further preferably in the range of 5 to 20%. Light-emitting diodes composed of inorganic substances can emit light brightly and have a long life even when the light emitting surface is small. Therefore, in the case where the light-emitting element 25 is a light-emitting diode composed of inorganic substances, a bright display can be performed even if the aperture ratio of the black matrix 32 is reduced. In addition, if the aperture ratio of the black matrix 32 is reduced, the reflection of external light can be suppressed, and a darker black can be displayed, thereby achieving a higher contrast.

[0100] The thickness of the black matrix 32 is preferably in the range of 1 to 30 μm, more preferably in the range of 1 to 15 μm, and further preferably in the range of 1 to 5 μm. A thicker black matrix 32 is advantageous in achieving higher light-shielding properties. However, if the black matrix 32 is made thicker, in the pattern exposure performed on the coating film composed of the photosensitive black composition, the light cannot reach the deep part of the coating film with sufficient intensity, and it is possible that a higher shape accuracy cannot be achieved.

[0101] like Figures 3 to 6 As shown, the outer coating layer 33OC covers the black matrix 32 and fills the third through hole of the black matrix 32. The outer coating layer 33OC is composed of, for example, a transparent resin. According to an example, the outer coating layer 33OC is colorless and transparent. The outer coating layer 33OC can further contain one or more of an ultraviolet absorber, a yellow pigment, and transparent particles. The outer coating layer 33OC provides a flat base relative to the resin layer 34 and the like.

[0102] The resin layer 34 is provided on the overcoat layer 33OC. According to one example, the resin layer 34 is transparent. In this case, the resin layer 34 may be colored or colorless. The resin layer 34 may also have light scattering properties.

[0103] The resin layer 34 has first through holes at the positions of the third through holes. These first through holes constitute a first through hole group corresponding to the third through hole group described above. Each first through hole group is composed of three first through holes arranged along the X direction. The first through hole group is arranged along the first direction and the second direction intersecting each other, here, along the X direction and the Y direction.

[0104] like Figure 7 As shown, the distance W between adjacent first through hole groups in the X direction is x 1 is greater than the distance W between the first through holes included in the same through hole group x 2. The distance W between adjacent first through hole groups in the Y direction y 1 is also greater than the distance W between the first through holes included in the same through hole group. x 2.

[0105] Distance W x 2 is preferably in the range of 5 to 80 μm, more preferably in the range of 5 to 40 μm, further preferably in the range of 5 to 20 μm.

[0106] Distance W x 1 is preferably in the range of 5 to 250 μm, more preferably in the range of 50 to 214.5 μm, further preferably in the range of 100 to 214.5 μm.

[0107] Distance W y 1 is preferably in the range of 5 to 250 μm, more preferably in the range of 5 to 100 μm, further preferably in the range of 5 to 50 μm.

[0108] Distance W x 1 and distance W x 2 ratio W x 1 / W x 2 is preferably in the range of 0.5 to 20, more preferably in the range of 2 to 20, and further preferably in the range of 10 to 20. Distance W x 1 can be related to the distance W x 2 is equal to or smaller than the distance W x 2.

[0109] Distance W y 1 and distance W x 2 ratio W y 1 / W x 2 is preferably in the range of 0.5 to 40, more preferably in the range of 1 to 10, and further preferably in the range of 1.1 to 5. Distance W y 1 can be related to the distance W x 2 is equal to or smaller than the distance W x 2.

[0110] The portion sandwiched by the adjacent first through holes in the resin layer 34 is a partition wall. These partition walls have a rectangular cross-sectional shape. These partition walls may have a positive cone cross-sectional shape or an inverted cone cross-sectional shape. In addition, these partition walls form recesses (first through holes) at the positions of the first sub-pixel PXR, the second sub-pixel PXG, and the third sub-pixel PXB. Here, these recesses (first through holes) have a groove shape extending along the Y direction.

[0111] The thickness T of the resin layer 34 is preferably in the range of 5 to 50 μm, more preferably in the range of 5 to 40 μm, and further preferably in the range of 10 to 25 μm. When the thickness T of the resin layer 34 is small, it is not easy to increase the total thickness of the layers formed in the first through hole. When the thickness T of the resin layer 34 is increased, the shape accuracy of the partition wall portion sandwiched between adjacent first through holes is reduced.

[0112] The inorganic cover layer 35 includes a plurality of first portions that at least partially cover the sidewalls of the plurality of first through holes. Figures 3 to 6 As shown, the inorganic covering layer 35 covers the entire side wall of each of the first through holes. The inorganic covering layer 35 may not cover a portion of the side wall of the first through hole. For example, the inorganic covering layer 35 may not cover at least one of the portion near the black matrix 32 in at least one side wall of the first through hole and the portion near the upper surface of the resin layer 34 in at least one side wall of the first through hole.

[0113] The coverage of the first portion of the inorganic cover layer 35 on the side wall of the first through hole is 60% or more. When the coverage of the side wall by the first portion is 60% or more, when a coating is formed in the recessed portion (first through hole) formed by the partition wall, for example, by die coating or nozzle coating, it is possible to effectively suppress the generation of bubbles between the inner surface of the recessed portion and the coating and in the coating. The coverage of the first portion of the inorganic cover layer 35 on the side of the first through hole is preferably 80% or more.

[0114] The inorganic cover layer 35 also includes a plurality of second portions, which extend at the positions of the openings of the plurality of first through holes on the transparent substrate 31 side and each have a second through hole smaller in size than the opening. That is, the inorganic cover layer 35 also includes a second portion covering the outer coating 33OC in the first through hole. The second portion has a second through hole smaller in size than the opening of the first through hole on the transparent substrate 31 side. Here, as Figure 5 As shown, the inorganic cover layer 35 has a second through hole at the position of the third through hole of the black matrix 32. The second portion can be omitted.

[0115] The inorganic covering layer 35 further includes a plurality of third portions that at least partially cover the upper surface of the resin layer 34. Here, the third portion covers the entire upper surface of the resin layer 34. The third portion preferably includes a portion adjacent to the first portion.

[0116] The inorganic cover layer 35 may have a single layer structure or a multilayer structure. The layer included in the inorganic cover layer 35 is, for example, a metal, an alloy or a transparent dielectric. According to one example, the inorganic cover layer 35 is composed of aluminum or an aluminum alloy. The inorganic cover layer 35 is preferably such that the contact angle of the surface relative to the coating liquid is in the range of 1 to 30 degrees, more preferably in the range of 5 to 10 degrees.

[0117] Below, refer to Figure 8 The first through holes included in the resin layer 34 , the second through holes included in the inorganic cover layer 35 , and the third through holes included in the black matrix 32 will be described. Figure 8 It means from Figure 7 A top view of the structure of the wavelength conversion substrate 3A after omitting some of the components. Specifically, Figure 8 It means from Figure 7 A top view of the structure after the first wavelength conversion layer 36R, the second wavelength conversion layer 36G, and the filling layer 36B are omitted in the wavelength conversion substrate 3A. Figure 8 , the length L1 and the width W1 are respectively the size in the X direction and the size in the Y direction of the opening of the first through hole on the transparent substrate 31 side of the resin layer 34. The length L2 and the width W2 are respectively the size in the X direction and the size in the Y direction of the opening of the second through hole on the transparent substrate 31 side of the inorganic cover layer 35. The length L3 and the width W3 are respectively the size in the X direction and the size in the Y direction of the opening of the third through hole on the transparent substrate 31 side of the black matrix 32.

[0118] The first through hole has an opening length L1 on the transparent substrate 31 side in the range of 10 to 1000 μm, and a ratio W1 / L1 of the width W1 of the opening to the length L1 in the range of 0.01 to 0.95. The opening of the first through hole has a shape extending in the Y direction with this size, so that bubbles are not easily generated when the coating liquid is filled into the first through hole. For the same reason, the depth of the first through hole is preferably in the range of 1 to 100 μm, and more preferably in the range of 10 to 50 μm.

[0119] The length L1 of the first through hole is preferably in the range of 90 to 600 μm. The ratio W1 / L1 of the width W1 of the first through hole to the length L1 is preferably in the range of 0.01 to 0.75. When the above-mentioned coating is performed at a high speed, bubbles may be generated between the inner surface of the recess formed by the partition wall and the coating film or in the coating film. When the length L1 and the ratio W1 / L1 are made within the above-mentioned range, the position of the bubbles generated when coating is performed at a high speed can be limited to one end of the length direction of the recess. Therefore, the brightness reduction and color loss of the display device caused by bubbles can be suppressed.

[0120] exist Figure 8 In the embodiment, the opening of the third through hole is such that the ratio L3 / L1 of the dimension L3 in the length direction (Y direction) of the first through hole to the length L1 is preferably in the range of 0.01 to 0.80. When the ratio L3 / L1 is in this range, even if bubbles are generated at one end of the recessed portion, the influence of the bubbles on the display can be effectively suppressed. The ratio L3 / L1 is more preferably in the range of 0.15 to 0.50.

[0121] exist Figure 8 In the embodiment, the opening of the second through hole is arranged so that the contour of the orthographic projection onto the first main surface (hereinafter referred to as the second contour) respectively surrounds the contour of the orthographic projection of the third through hole onto the first main surface (hereinafter referred to as the third contour). The second contour may not surround the third contour. In the case of adopting a structure in which the second contour surrounds the third contour, it is not easy to produce a reduction in contrast due to a positional error of the second through hole. In the second through hole, the ratio L2 / L1 of the dimension L2 in the length direction (Y direction) of the first through hole to the above-mentioned length L1 is preferably in the range of 0.01 to 0.80, and more preferably in the range of 0.15 to 0.50.

[0122] The first wavelength conversion layer 36R, the second wavelength conversion layer 36G, and the filling layer 36B are filling portions provided in the first through holes, respectively.

[0123] The first wavelength conversion layer 36R fills the first through hole at the position of the first sub-pixel PXR. The first wavelength conversion layer 36R is a layer containing a fluorescent material such as a quantum dot fluorescent material and a transparent resin. As described above, the first wavelength conversion layer 36R converts the blue light emitted by the light emitting element D of the first sub-pixel PXR into red light.

[0124] The second wavelength conversion layer 36G fills the first through hole at the position of the second sub-pixel PXG. The second wavelength conversion layer 36G is a layer containing a fluorescent substance such as a quantum dot fluorescent substance and a transparent resin. As described above, the second wavelength conversion layer 36G converts the blue light emitted by the light emitting element D of the second sub-pixel PXG into red light.

[0125] The filling layer 36B fills the first through hole at the position of the third sub-pixel PXB. As described above, the filling layer 36B is a colorless and transparent layer. In this case, the filling layer 36B is made of, for example, a transparent resin.

[0126] The adhesive layer 4 is sandwiched between the light-adjusting substrate 2 and the wavelength conversion substrate 3A to bond them to each other. The adhesive layer 4 transmits the light emitted by the light-emitting element 25. The adhesive layer 4 is, for example, a colorless and transparent layer. The adhesive layer 4 is made of an adhesive or a pressure-sensitive adhesive.

[0127] This display device 1A can be manufactured by the following method, for example.

[0128] In manufacturing the display device 1A, first, the wavelength conversion substrate 3A is prepared.

[0129] That is, first, a structure including the transparent substrate 31, the black matrix 32, the overcoat layer 33OC and the resin layer 34 is obtained before the inorganic cover layer 35, the first wavelength conversion layer 36R, the second wavelength conversion layer 36G and the filling layer 36B are formed on the wavelength conversion substrate 3A.

[0130] The black matrix 32 can be formed by, for example, photolithography using a negative-type photosensitive black composition. The overcoat layer 33OC can be formed by, for example, sequentially applying a resin and curing the coating film.

[0131] The resin layer 34 can be obtained by, for example, photolithography using a negative photosensitive composition. By appropriately setting exposure conditions and development conditions, etc., a structure having the above-mentioned first through-hole can be formed.

[0132] Next, the inorganic cover layer 35 is formed. Specifically, the material of the inorganic cover layer 35 is deposited on the resin layer 34 and the outer coating layer 33OC by a vapor deposition method such as a sputtering method and a vacuum evaporation method. In this way, the inorganic cover layer 35 including the OC covering portion covering the outer coating layer 33OC in addition to the third portion covering the upper surface of the resin layer 34 and the first portion covering the side surface of the first through hole can be obtained.

[0133] Next, an etching mask is formed. The etching mask is formed so that the portion of the inorganic cover layer 35 where the second through hole is formed is exposed and the other portion is covered by the etching mask. The etching mask can be formed by photolithography using a photosensitive resin.

[0134] Next, a second through hole is formed in the OC cover portion by etching such as wet etching.

[0135] Next, the etching mask is removed, and then the first wavelength conversion layer 36R, the second wavelength conversion layer 36G, and the filling layer 36B are formed.

[0136] Each of the first wavelength conversion layer 36R, the second wavelength conversion layer 36G, and the filling layer 36B can be formed by, for example, a photolithography method using a negative photosensitive composition.

[0137] Specifically, a negative photosensitive material as a material of the first wavelength conversion layer 36R is applied to the surface of the structure obtained by the above etching, for example, by die coating. In the die coating, for example, the above structure and the slot mold are configured so that the length direction of the slot is parallel to the X direction, and the coating liquid is discharged from the slot mold while moving them relatively in the Y direction. In this way, a coating film is formed on the surface of the above structure. Next, the coating film is pattern-exposed to solidify the photosensitive material that fills the first through hole at the position of the first sub-pixel PXR. Thereafter, the unexposed portion of the coating film is removed by development. Thus, the first wavelength conversion layer 36R is obtained.

[0138] Next, a negative photosensitive material, which is a material of the second wavelength conversion layer 36G, is applied to the surface of the structure after the first wavelength conversion layer 36R is formed, for example, by die coating in the same manner as described above. Next, the coating film is pattern-exposed to cure the photosensitive material that fills the first through hole at the position of the second sub-pixel PXG. Thereafter, the unexposed portion of the coating film is removed by development. Thus, the second wavelength conversion layer 36R is obtained.

[0139] Finally, a negative photosensitive material, which is a material of the filling layer 36B, is applied to the surface of the structure after the first conversion layer 36R and the second conversion layer 36G are formed, for example, by die coating in the same manner as described above. Next, the coating film is pattern-exposed to cure the photosensitive material that fills the first through hole at the position of the third sub-pixel PXB. Thereafter, the unexposed portion of the coating film is removed by development. Thus, the filling layer 36B is obtained.

[0140] Alternatively, the first wavelength conversion layer 36R, the second wavelength conversion layer 36G, and the filling layer 36B can also be formed by a nozzle coating method. In the nozzle coating method, a nozzle head is used that is provided with a plurality of nozzles arranged at a pitch equal to that of the pixel PX in the X direction. Then, while the nozzle head is relatively moved in the Y direction relative to the etched structure obtained by the method described above, the resin composition as the material of the first wavelength conversion layer 36R is discharged from each nozzle into the recess formed by the partition at the position of the first sub-pixel PXR. In this way, the first wavelength conversion layer 36R is obtained by curing the coating formed in the recess. Then, the second wavelength conversion layer 36G and the filling layer 36B are also formed by the same method.

[0141] In addition, the order of forming the first wavelength conversion layer 36R, the second wavelength conversion layer 36G, and the filling layer 36B is arbitrary.

[0142] The wavelength conversion substrate 3A obtained as described above and the light control substrate 2 prepared separately are bonded together via the adhesive layer 4. Thus, the display device 1A is obtained.

[0143] When the above-described structure is employed for the wavelength conversion substrate 3A of the display device 1A, it is possible to prevent a decrease in brightness and a loss in color due to the generation of bubbles in the wavelength conversion layer from occurring.

[0144] <2> Second Embodiment

[0145] Fig. 9 It is a plan view showing a part of a display device according to a second embodiment of the present invention.

[0146] The display device 1B of the second embodiment includes a second substrate 10 instead of the wavelength conversion substrate 3A. Fig. 9 The display device 1A is the same as the display device 1A except for the wavelength conversion substrate 3B shown. The wavelength conversion substrate 3B is the same as the wavelength conversion substrate 3A except for the following configuration.

[0147] That is, the wavelength conversion substrate 3B includes a plurality of coloring layers sandwiched between the transparent substrate 31 and the outer coating 33OC, and respectively arranged at at least a portion of the third through hole. Here, the wavelength conversion substrate 3B includes a first coloring layer 33R that buries the third through hole at the position of the first sub-pixel PXR, and a second coloring layer 33G that buries the third through hole at the position of the second sub-pixel PXG. According to an example, the first coloring layer 33R and the second coloring layer 33G are a red coloring layer and a green coloring layer, respectively. The wavelength conversion substrate 3B can also include a third coloring layer that buries the first through hole at the position of the third sub-pixel PXB. In this case, for example, the first coloring layer 33R, the second coloring layer 33G, and the third coloring layer are a red coloring layer, a green coloring layer, and a blue coloring layer, respectively.

[0148] In the wavelength conversion substrate 3B, similar to the wavelength conversion substrate 3A, it is possible to prevent the brightness of the display device from being reduced and the color from being lost due to the generation of bubbles in the wavelength conversion layer. Furthermore, when the wavelength conversion substrate 3B is configured as described above, for example, in the first sub-pixel PXR and the second sub-pixel PXG, it is possible to prevent a portion of the light emitted by the light emitting element 25 from being used for display without being wavelength-converted. Therefore, higher color reproducibility can be achieved.

[0149] <3> Third embodiment

[0150] Fig.10 It is a plan view showing a part of a display device according to a third embodiment of the present invention.

[0151] The display device 1C of the third embodiment includes a second substrate 200 in place of the wavelength conversion substrate 3A. Fig.10 The wavelength conversion substrate 3C is the same as the display device 1A except for the case of the wavelength conversion substrate 3C shown. The wavelength conversion substrate 3C is the same as the wavelength conversion substrate 3B except for the case of adopting the following configuration.

[0152] That is, the wavelength conversion layer 35 of the wavelength conversion substrate 3C includes a third portion that partially covers the upper surface of the resin layer 34 and is adjacent to the first portion that covers the side wall of the first through hole. In the wavelength conversion substrate 3C, similar to the wavelength conversion substrate 3B, it is possible to prevent the brightness reduction and color loss of the display device caused by the generation of bubbles in the wavelength conversion layer, and achieve high color reproducibility.

[0153] <4> Fourth embodiment

[0154] Fig.11 It is a plan view showing a part of a display device according to a fourth embodiment of the present invention.

[0155] The display device 1D of the fourth embodiment includes a Fig.11 The wavelength conversion substrate 3D is the same as the display device 1A except for the case of the wavelength conversion substrate 3D shown. The wavelength conversion substrate 3D is the same as the wavelength conversion substrate 3B except for the case of adopting the following configuration.

[0156] That is, the wavelength conversion substrate 3D is such that the coverage of the side wall of the first through hole by the inorganic cover layer 35 is 100%. Fig. 9 The wavelength conversion substrate 3D is similar to the wavelength conversion substrate 3B, and is less likely to cause a decrease in brightness and color loss of the display device due to bubbles in the wavelength conversion layer, and can achieve higher color reproducibility.

[0157] <Comparative Example>

[0158] Fig.12 is a cross-sectional view of a display device 1X of a comparative example. The display device 1X is a display device in which the coverage of the side wall of the first through hole by the inorganic cover layer 35 is 100%. Fig. 9 The display device 1B is different from the display device 1B in that the coverage is 50%. Fig.13 is a cross-sectional view of a display device 1Y according to another comparative example. The display device 1Y is a display device in which the coverage of the side wall of the first through hole by the inorganic cover layer 35 is 100%. Fig. 9 The display device 1B of the comparative example is a display device that is different only in that the coverage is 0%. In any display device of the comparative example, the side wall of the first through hole has insufficient lyophilicity with respect to the coating liquid, and bubbles are easily generated.

[0159] Example

[0160] Hereinafter, simulations performed in connection with the present invention will be described.

[0161] (Example 1)

[0162] about Fig. 9 The wavelength conversion layer formation process in the manufacture of the wavelength conversion substrate 3B included in the display device 1B shown was simulated using the finite volume method analysis software Fluent, and the generation of bubbles in the coating film was investigated. Here, the VOF (Volume of Fluid) method was used in the calculation of the free interface. In addition, the simulation was performed assuming the following conditions. That is, the first through hole of the resin layer 34 is such that the length L1 of the opening on the side of the transparent substrate 31 is 468μm, the width W1 is 89.5μm, and the depth is 30μm. The contact angle of the coating liquid with respect to the surface composed of the resin is 44.5 degrees, and the contact angle of the coating liquid with respect to the inorganic covering layer 35 is 9.7 degrees. The coating liquid has a viscosity of 0.0416kg / m·s and a density of 998kg / m 3 , surface tension is 0.027N / m, flow rate is 0.1m / sec. In addition, this flow rate is equivalent to the relative movement speed of the structure and the slot mold along the Y direction when the coating liquid is applied to the surface of the structure before the wavelength conversion layer is formed in the wavelength conversion substrate 3B.

[0163] (Example 2)

[0164] The simulation was performed under the same conditions as in Example 1 except that the length L1 of the first through hole was changed to 368 μm.

[0165] (Example 3)

[0166] A simulation was performed under the same conditions as in Example 1 except that the length L1 of the first through hole was changed to 114 μm and the flow rate was changed to 0.01 m / sec.

[0167] (Example 4)

[0168] for Fig.11 The same simulation as above was performed for the wavelength conversion layer formation process in the manufacture of the wavelength conversion substrate 3D included in the display device 1D shown. The simulation was performed assuming the following conditions. That is, the length L1 of the first through hole was 114 μm, the flow rate was 0.01 m / sec, and the coverage of the side wall of the first through hole was 90%. The conditions other than these were the same as those in Example 1.

[0169] (Example 5)

[0170] for Fig.11The same simulation as above was performed for the wavelength conversion layer formation process in the manufacture of the wavelength conversion substrate 3D included in the display device 1D shown. The simulation was performed assuming the following conditions. That is, the length L1 of the first through hole was 114 μm, the flow rate was 0.01 m / sec, and the coverage of the side wall of the first through hole was 80%. The conditions other than these were the same as those in Example 1.

[0171] (Comparative Example 1)

[0172] A simulation was performed under the same conditions as in Example 1 except that the length L1 of the first through hole was changed to 89.5 μm.

[0173] (Comparative Example 2)

[0174] for Fig.12 The same simulation as above was performed for the wavelength conversion layer formation process in the manufacture of the wavelength conversion substrate 3X included in the display device 1X shown. The simulation was performed assuming the following conditions. That is, the length L1 of the first through hole was 114 μm, the flow rate was 0.01 m / sec, and the coverage of the side wall of the first through hole was 50%. The conditions other than these were the same as those in Example 1.

[0175] (Comparative Example 3)

[0176] for Fig.13 The wavelength conversion layer forming process in the manufacture of the wavelength conversion substrate 3Y included in the display device 1Y shown was simulated in the same manner as described above. The simulation was performed assuming the following conditions. That is, the length L1 of the first through hole was set to 114 μm, the flow rate was set to 0.01 m / sec, and the coverage of the side wall of the first through hole was set to 0%. The conditions other than these were the same as those in Example 1.

[0177] <Evaluation>

[0178] The results of the above simulations are shown in Table 1 and Figures 14 to 21 In Table 1, “coverage” refers to the coverage of the side wall of the first through hole by the inorganic covering layer.

[0179] [Table 1]

[0180]

[0181] According to Table 1 and Figures 14 to 21 The following information can be obtained.

[0182] That is, as can be seen from the comparison between Examples 3, 4, and 5 and Comparative Examples 2 and 3, bubbles can be generated when the coating speed is low by making the ratio W1 / L1 sufficiently small and making the coverage of the side wall of the first through hole by the inorganic covering layer sufficiently large.

[0183] As can be seen from Examples 1, 2 and Comparative Example 1, when the flow rate is increased, bubbles may be generated regardless of the ratio W1 / L1 and the coverage. However, when the coverage of the side wall of the first through hole by the inorganic cover layer is large enough, the size of the bubble can be reduced by reducing the ratio W1 / L1 until the shape of the first through hole becomes a groove, and the bubble generation position can be limited to one end of the groove (the end on the downstream side of the coating liquid flow). Therefore, by separating the third through hole of the black matrix from the bubble generation position, the effect of the bubble generation on the display can be reduced.

[0184] Furthermore, as can be seen from the comparison between Example 3 and Comparative Examples 2 and 3, the generation of bubbles can be suppressed by increasing the coverage of the side surface of the first through hole by the inorganic covering layer and increasing the area of ​​the lyophilic region contacted by the coating liquid.

[0185] Based on the above, Examples 1 to 5 and Comparative Examples 1 to 3 were evaluated based on the following criteria. The results are shown in Table 1.

[0186] [Evaluation A]

[0187] A decrease in brightness and a loss in color of a display device caused by bubbles can be suppressed.

[0188] [Evaluation B]

[0189] The bubbles may cause a decrease in brightness and a loss in color of the display device.

[0190] Explanation of symbols

[0191] 1A: display device, 1B: display device, 1C: display device, 1D: display device, 1X: display device, 1Y: display device, 2: dimming substrate, 3A: wavelength conversion substrate, 3B: wavelength conversion substrate, 3C: wavelength conversion substrate, 3D: wavelength conversion substrate, 3X: wavelength conversion substrate, 3Y: wavelength conversion substrate, 4: adhesive layer, 21: substrate, 22: semiconductor layer, 23A: conductor layer, 23B: conductor layer, 23C: conductor layer, 23D: conductor layer, 24A: insulating layer, 24B: insulating layer, 24C: insulating layer, 25: light emitting element, 26: partition layer, 27: filling layer, 28: conductor layer, 31: transparent Substrate, 32: black matrix, 33G: second coloring layer, 33R: first coloring layer, 34: resin layer, 35: inorganic covering layer, 36B: filling layer, 36G: second wavelength conversion layer, 36R: first wavelength conversion layer, 251: first layer, 252: second layer, 253: third layer, C: capacitor, D: light emitting element, DR: drive control element, L: light, PSL: power line, PX: pixel, PXB: third sub-pixel, PXG: second sub-pixel, PXR: first sub-pixel, SDR: scanning signal line driver, SSL: scanning signal line, SW: switch, VDR: image signal line driver, VSL: image signal line, W x 1: Distance, W x 2: Distance, W y 1: distance, L1: distance, L2: distance, L3: distance, W1: distance, W2: distance, W3: distance.

Claims

1. A wavelength conversion substrate, comprising: A transparent substrate having a first main surface and a second main surface; A resin layer, disposed on the first main surface, having a plurality of first through holes; an inorganic covering layer including a plurality of first portions respectively covering at least partially the sidewalls of the plurality of first through holes; and The wavelength conversion layer includes a plurality of wavelength conversion parts respectively disposed in at least a portion of the plurality of first through holes. The coverage of the side wall by the first part is more than 60%, For each of the plurality of first through holes, a length L1 of the opening on the transparent substrate side is within a range of 10 to 1000 μm, and a ratio W1 / L1 of a width W1 of the opening on the transparent substrate side to the length L1 is within a range of 0.01 to 0.

95.

2. The wavelength conversion substrate according to claim 1, wherein: The inorganic cover layer further includes a plurality of second portions, each extending at the position of the openings of the plurality of first through holes on the transparent substrate side and each having a second through hole having a size smaller than the opening.

3. The wavelength conversion substrate according to claim 2, wherein: The ratio W1 / L1 is in the range of 0.01 to 0.75, and the ratio L2 / L1 of the dimension L2 of the second through hole in the longitudinal direction of the plurality of first through holes to the length L1 is in the range of 0.01 to 0.

80.

4. The wavelength conversion substrate according to claim 1 or 2, wherein: The inorganic cover layer further includes a third portion that at least partially covers the upper surface of the resin layer and is adjacent to the first portion.

5. The wavelength conversion substrate according to claim 4, wherein: The coverage rate of the third portion on the upper surface is greater than 80%.

6. The wavelength conversion substrate according to any one of claims 1 to 5, wherein: The depth of each of the plurality of first through holes is in the range of 10 to 40 μm.

7. The wavelength conversion substrate according to any one of claims 1 to 6, wherein: The inorganic covering layer is made of metal or alloy.

8. The wavelength conversion substrate according to any one of claims 1 to 7, wherein: The wavelength conversion substrate further includes a black matrix that is interposed between the transparent substrate and the resin layer and has a plurality of third through holes at positions of the plurality of first through holes.

9. The wavelength conversion substrate according to claim 8, wherein: The ratio W1 / L1 is in the range of 0.01 to 0.75, and the ratio L3 / L1 of the dimension L3 of the third through hole in the longitudinal direction of the plurality of first through holes to the length L1 is in the range of 0.01 to 0.

80.

10. The wavelength conversion substrate according to claim 8 or 9, wherein: The wavelength conversion substrate further includes a color filter including a plurality of colored layers respectively arranged at positions of at least a portion of the plurality of third through holes.

11. A display device comprising: The wavelength conversion substrate according to any one of claims 1 to 10; and The dimming device is arranged to face the first main surface.

12. The display device according to claim 11, wherein: The dimming device includes a substrate and a plurality of light emitting diodes arranged on the substrate corresponding to the plurality of first through holes.

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