Display device and manufacturing method thereof

Abstract

To provide a display device and its manufacturing method which can effectively reduce excitation light leakage without deterioration in a color conversion layer, so as to improve color purity.SOLUTION: A display device includes a plurality of display pixels respectively having: a plurality of light emitters provided on a substrate; a color conversion layer provided on the light emitters; and a color filter provided on the color conversion layer. A spectral transmission factor of the color filter is 30% or less in emission peak wavelengths of the light emitters, and is 80% or more in a peak wavelength of fluorescence transmitted by the color conversion layer.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a display device and a manufacturing method thereof. [Background technology]

[0002] Patent Document 1 discloses an invention related to a micro LED display device. Patent Document 1 specifies the refractive index difference between the sealing portion that seals each micro LED and the low refractive index layer laminated thereon.

[0003] Patent Document 2 discloses a display element and a display device in which a wavelength conversion section and a reflective layer that reflects the excitation light transmitted through the wavelength conversion section are stacked on a light source section that emits excitation light, and the reflective layer is formed from a dielectric multilayer film. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2022 / 209031 [Patent Document 2] Patent Publication No. 2022-096625 Summary of the Invention [Problem to be solved by the invention]

[0005] Although Patent Document 1 describes that a color filter may be provided on the low refractive index layer, it does not provide a detailed description of the color filter.

[0006] In Patent Document 2, a dielectric multilayer film is formed on the wavelength conversion section, but the dielectric multilayer film is composed of a multilayer film in which a low refractive index material and a high refractive index material are laminated, so the number of manufacturing steps is very large. In addition, the high heat generated during the process of forming the dielectric multilayer film affects the wavelength conversion section below, deteriorating the quantum dots contained in the wavelength conversion section. In addition, Patent Document 2 does not disclose the spectral characteristics of the dielectric multilayer film that can sufficiently reduce the leakage of excitation light.

[0007] Therefore, the present invention has been made in consideration of these points, and aims to provide a display device and a manufacturing method thereof that can effectively reduce excitation light leakage and improve color purity without deteriorating the color conversion layer. [Means for solving the problem]

[0008] One embodiment of the display device of the present invention comprises a plurality of display pixels each having a plurality of light-emitting elements arranged on a substrate, a color conversion layer arranged on the light-emitting elements, and a color filter arranged on the color conversion layer, wherein the spectral transmittance of the color filter at the emission peak wavelength of the light-emitting elements is 30% or less, and the spectral transmittance of the color filter at the fluorescence peak wavelength transmitted through the color conversion layer is 80% or more.

[0009] One embodiment of the method for producing a display device of the present invention is the method for producing the display device described above, characterized in that the color filter is formed at a heat treatment temperature of 150° C. or less. Effect of the Invention

[0010] According to the display device of the present invention, the leakage of excitation light can be effectively reduced and color purity can be improved.

[0011] Furthermore, according to the method for manufacturing a display device, the heat treatment temperature during the formation of the color filter can be reduced, and the influence on the color conversion layer, in particular the deterioration of the quantum dots contained in the color conversion layer, can be suppressed. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a schematic cross-sectional view of a micro LED display as a display device in this embodiment. [Diagram 2] FIG. 2 shows the emission spectrum of a blue light-emitting element. [Diagram 3] FIG. 3 shows the fluorescence spectrum of the green quantum dots. [Figure 4] FIG. 4 shows the fluorescence spectrum of the red quantum dots. [Diagram 5] FIG. 5 shows the transmittance spectrum of the color filters. [Figure 6] FIG. 6 shows the emission spectrum (green) when a color filter is laminated. [Figure 7] FIG. 7 shows the emission spectrum (red) when a color filter is laminated. [Figure 8] FIG. 8 is a graph showing the relationship between the emission wavelength of a light-emitting element and the chromaticity reproduction range (NTSC ratio). [Figure 9] FIG. 9 is a schematic cross-sectional view showing a manufacturing process of the micro LED display of the present embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] The following describes the embodiments of the present invention in detail, but the following description is an example (representative example) of the embodiments of the present description, and the present invention is not limited to these contents as long as it does not deviate from the gist of the present invention. In addition, the notation "~" used below includes both the lower limit and the upper limit within the range.

[0014] <How the display device of this embodiment was invented> Liquid crystal on silicon (LCOS), laser beam scanning (LBS) or organic light emitting diode (OLED) microdisplays are becoming mainstream for head mounted displays for AR (Augmented Reality) / MR (Mixed Reality) and other applications. However, these methods do not provide sufficient brightness in outdoor light, and are primarily used indoors.

[0015] In contrast, the micro LED method is considered to have an advantage over the above methods in terms of brightness, and its application is expected to expand in the future.

[0016] As a method for displaying full color using a micro LED display, a technology has been proposed in which blue light-emitting elements are applied to the light-emitting elements (LEDs) and color conversion (wavelength conversion) is performed using a color conversion layer using quantum dots, for example, to enable RGB display.

[0017] Patent Document 1 describes that a low refractive index layer may be provided on the color conversion layer, and a color filter may further be provided on the low refractive index layer. However, detailed characteristics of the color filter are not disclosed.

[0018] In addition, in Patent Document 2, since it is necessary to form a dielectric multilayer film, there are concerns that the number of steps will increase and that the quantum dots contained in the color conversion layer will deteriorate due to heat acting on the color conversion layer when the dielectric multilayer film is formed. In addition, the spectrum of the dielectric multilayer film required to remove blue light noise is not clarified.

[0019] Therefore, the present inventors have conducted extensive research and have developed a display device that can effectively reduce the leakage of excitation light and improve color purity.

[0020] <Description of the display device according to this embodiment> The display device in this embodiment is configured as a micro LED (Light Emitting Diode) display 1 shown in Fig. 1. Fig. 1 is a schematic cross-sectional view of the micro LED display 1.

[0021] As shown in Fig. 1, the micro LED display 1 includes a number of display pixels 2a, 2b, and 2c. For example, the display pixel 2a shown in Fig. 1 is a red display pixel, the display pixel 2b is a green display pixel, and the display pixel 2c is a blue display pixel.

[0022] 1, a plurality of light-emitting elements (LEDs) 4 are disposed on a substrate 3. For example, the light-emitting elements 4 are arranged in a matrix on the substrate 3. Each of the light-emitting elements 4 is a blue light-emitting element.

[0023] As shown in Fig. 1, a partition layer 5 is formed on a substrate 3 to separate the light emitting elements 4. The side surfaces 5a of the partition layer 5 shown in Fig. 1 extend vertically in the height direction from the surface of the substrate 3, but the side surfaces 5a may be inclined so that the width of each partition layer 5 becomes wider as it approaches the substrate 3. The bottom portion of the partition layer 5 may be a concave curved surface.

[0024] The partition layer 5 has a function of reflecting light, and is made of, for example, a white wall material. In order to obtain high light conversion efficiency in the micro LED display 1, the partition layer 5 is preferably high in height, and although not limited thereto, the height is preferably about 3 μm to 6 μm, and more preferably about 4 μm to 6 μm.

[0025] As shown in Fig. 1, the internal space of each partition layer 5 of the red display pixel 2a and the green display pixel 2b is filled with color conversion layers 6a and 6b. As shown in Fig. 1, in the color conversion layers, red quantum dots 7 and green quantum dots 8 are dispersed in the red display pixel 2a and the green display pixel 2b, respectively.

[0026] The quantum dots 7 and 8 are dispersed in a resin 9. The resin 9 is preferably a transparent resin. There is no limitation on the material of the resin 9, but examples of the material include an acrylic resin, a polyurethane resin, a polyester resin, a polyolefin resin, a polycarbonate resin, a polyethyleneimine resin, an epoxy resin, and a thioether resin.

[0027] The red quantum dots 7 preferably have a fluorescence peak wavelength of 600 nm to 680 nm, and the green quantum dots 8 preferably have a fluorescence peak wavelength of 520 nm to 560 nm. These quantum dots 7 and 8 absorb blue light as excitation light irradiated from the light emitting element 4, and emit light by color conversion to red or green.

[0028] Although there is no limitation on the material, since the use of cadmium (Cd) is restricted in various countries due to its toxicity, it is preferable that the quantum dots 7 and 8 are cadmium-free. In addition, the quantum dots 7 and 8 preferably have a core-shell structure with a core and a shell covering the surface of the core, such as ZnSe / ZnS, ZnSe / ZnSeS, ZnTe / ZnS, ZnSeTe / ZnS, InP / ZnS, etc. However, the quantum dots 7 and 8 may be composed of only a core. In order to improve dispersibility, it is preferable that the quantum dots 7 and 8 have a ligand (organic ligand) on the surface.

[0029] The quantum dots 7, 8 have a particle size of several nm to several tens of nm. The fluorescence peak wavelength can be controlled by adjusting the particle size and composition. The color conversion layers 6a, 6b may contain phosphors other than the quantum dots 7, 8.

[0030] On the other hand, as shown in Fig. 1, the internal space of the partition layer 5 of the blue display pixel 2c is filled with a resin 9, but does not contain quantum dots. The resin 9 is preferably a transparent resin. "Transparent" means that the visible light transmittance is 50% or more, preferably 70% or more, and most preferably 90% or more. The visible light transmittance can be measured in accordance with JIS K 7375:2008.

[0031] As another example, white light may be used for the light emitting element 4 used in the blue display pixel 2c, and blue quantum dots may be mixed into the resin 9.

[0032] 1, the surfaces of the color conversion layers 6a, 6b and the resin 9 may be formed at substantially the same height as the partition layer 5, or may be slightly lower than the partition layer 5. The thickness of the color conversion layers 6a, 6b is about 3 to 6 μm.

[0033] 1, a color filter 11 is provided on the surfaces of the color conversion layers 6a, 6b and the resin 9 via a barrier layer 10. The color filter 11 includes a red filter 11a, a green filter 11b, and a blue filter 11c.

[0034] Although the barrier layer 10 is not an essential layer, the provision of the barrier layer 10 can reduce the thermal influence on the quantum dots 7 and 8 of the color conversion layers 6a and 6b when the color filter 11 is formed. Furthermore, if there are irregularities between the surfaces of the partition layer 5 and the color conversion layers 6a and 6b and the resin 9, the barrier layer 10 can smooth out the irregularities. This allows the color filter 11 to be formed on a flat surface. Although the material of the barrier layer 10 is not limited, it is preferably an oxide film or a nitride film, and is formed of, for example, SiO2. Although the thickness of the barrier layer 10 is not limited, it is about 50 nm to 1 μm.

[0035] In the color filter 11, a red filter 11a is disposed at the position of the red display pixel 2a, a green filter 11b is disposed at the position of the green display pixel 2b, and a blue filter 11c is disposed at the position of the blue display pixel 2c.

[0036] Red filter 11a absorbs blue light having a short wavelength and transmits red light, green filter 11b absorbs blue light having a short wavelength and transmits red light, and blue filter 11c transmits blue light.

[0037] As shown in FIG. 1, microlenses 12a to 12c can be provided on the surface of the color filter 11. The microlenses 12a to 12c have optical transparency. Although not limited thereto, the microlenses 12a to 12c can be formed of, for example, an organic material such as acrylic resin, epoxy resin, or silicon resin, or an inorganic material such as SiN or SiO2. As shown in FIG. 1, the microlenses 12a to 12c are convex lenses, but they can also be concave lenses. The surface shape of the microlenses 12a to 12c can be changed in various ways depending on the relationship with the refractive index of the layer located on the surface of the microlenses 12a to 12c.

[0038] <Characteristic configuration of the micro LED display 1 according to the present embodiment> The micro LED display 1 of this embodiment has the following features. (1) The spectral transmittance of the color filter 11 at the emission peak wavelength of the light emitting element 4 is 30% or less. (2) The spectral transmittance of color filter 11 at the peak wavelength of the fluorescence transmitted through color conversion layers 6a, 6b is 80% or more.

[0039] The features of the micro LED display 1 of this embodiment will be described below using the spectral characteristics of the light emitting element 4, the quantum dots 7 and 8, and the color filter 11 applied to this embodiment.

[0040] Figure 2 shows the emission spectrum of the blue light-emitting element. The horizontal axis of Figure 2 is wavelength (nm) and the vertical axis is spectral irradiance. As shown in Figure 2, the emission peak wavelength was about 450 nm.

[0041] The arrow L1 irradiated from the light emitting element 4 shown in FIG. 1 indicates blue light (excitation light).

[0042] Figure 3 shows the fluorescence spectrum of the green quantum dots 8. The green quantum dots 8 used in this experiment were InSe (particle size = 2 to 10 nm). The thickness of the color conversion layer 6b was set to 6 µm. The horizontal axis of Figure 3 shows the wavelength (nm), and the vertical axis shows the spectral irradiance.

[0043] The blue light emitted from the light-emitting element 4 is color-converted to green light by the green quantum dots 8. As shown in FIG. 3, a fluorescence peak wavelength was observed at approximately 550 nm. This shows that the blue light is color-converted to green light. On the other hand, a peak of low emission intensity was observed at approximately 450 nm, which indicates blue light, and it was found that excitation light from the light-emitting element 4 remains. FIG. 1 shows that the blue light L1 is color-converted to green light L2 by the green quantum dots 8, but also shows that some of the blue light L1 passes through the color conversion layer 6b.

[0044] Fig. 4 shows the fluorescence spectrum of the red quantum dots 7. The red quantum dots 7 used in this experiment were InSe (particle size = 2 to 10 nm). The thickness of the color conversion layer 6b was set to 6 µm. The horizontal axis of Fig. 3 shows the wavelength (nm), and the vertical axis shows the spectral irradiance.

[0045] The blue light emitted from the light-emitting element 4 is color-converted to red light by the red quantum dots 7. As shown in FIG. 4, a fluorescence peak wavelength was observed at approximately 620 nm. It can be seen that the blue light is color-converted to red light. On the other hand, a peak of low emission intensity was observed at approximately 450 nm, which indicates blue light, and it was found that the excitation light from the light-emitting element 4 remains. FIG. 1 shows that the blue light L1 is color-converted to red light L3 by the red quantum dots 7, but also shows that a part of the blue light L1 is transmitted through the color conversion layer 6a.

[0046] 5 shows the spectrum of the transmittance of the color filter 11. Fig. 5 shows the spectrum of the red filter 11a and the green filter 11b of the color filter 11 shown in Fig. 1. In this experiment, the thickness of the color filter was changed to change the transmittance of the color filter.

[0047] As shown in Fig. 5, five types each of red filters 11a and green filters 11b with different thicknesses were prepared. First, considering the green filter 11b, the spectral transmittance at a wavelength of 450 nm, which is the emission peak wavelength of the blue light-emitting element, was able to be reduced to 30% or less. For example, the value of "G1.2%" on the graph line indicates that the spectral transmittance at a wavelength of 450 nm for the green (G) filter 11b is 1.2%. R indicates the red filter 11a. The same applies to the other graph lines.

[0048] On the other hand, the spectral transmittance was able to be increased to 80% or more at the fluorescence peak wavelength of 550 nm shown in the spectrum of Fig. 3. In this way, green filter 11b satisfies both of the above-mentioned characteristics (1) and (2).

[0049] Next, considering the red filter 11a, the spectral transmittance at 450 nm, which is the emission peak wavelength of the blue light-emitting element, can be reduced to 30% or less. On the other hand, the spectral transmittance at 620 nm, the fluorescence peak wavelength shown in the spectrum of Fig. 4, can be reduced to 80% or more. In this way, the red filter 11a satisfies both of the above-mentioned characteristics (1) and (2).

[0050] The color filter 11 of this embodiment will be described in more detail. The color filter 11 used in this embodiment is formed of a color filter material that hardens at a low temperature. Here, "low temperature" refers to a temperature at which the quantum dots 7 and 8 dispersed in the color conversion layers 6a and 6b are not easily deteriorated (oxidized) by heat in the film formation process of the color filter 11, specifically, 150°C or lower. As described above, the quantum dots 7 and 8 used in this embodiment are preferably cadmium-free, and have, for example, ZnSe or InP as a core. Furthermore, a shell that covers the surface of the core is formed of ZnS or the like. The cadmium-free quantum dots 7 and 8 can be effectively suppressed from being oxidized by setting the heating temperature of the color filter material to 150°C or lower.

[0051] The low-temperature curable color filter material includes, but is not limited to, a colorant, a photopolymerizable monomer, a photopolymerization initiator, and a resin, and the photopolymerizable monomer is

[0052] [CH2=CHC(=O)-(OC m H 2m ) n -OCH2]3-CCH2CH3 (In general formula (1), m represents an integer of 1 to 3, n represents an integer of 0 to 2, and multiple m's and multiple n's may be the same or different.) It is preferred that the compound contains the compound represented by the formula: The photopolymerization initiator preferably contains an oxime ester-based photopolymerization initiator.

[0053] In addition, the resin preferably contains a photosensitive acrylic resin. For example, the photosensitive acrylic resin is preferably a resin obtained by reacting a hydroxyl group of a hydroxyl-containing polymer obtained by polymerizing an ethylenically unsaturated monomer (c) containing a hydroxyl-containing ethylenically unsaturated monomer (b) with an isocyanate group and one or more (meth)acryloyl groups in the presence of a reaction product of a hydroxyl group of a compound (a) having two hydroxyl groups and one thiol group in a molecule and an acid anhydride group of pyromellitic anhydride and / or trimellitic anhydride, with an isocyanate group of a compound (d) having one isocyanate group and one or more (meth)acryloyl groups. Furthermore, the content of the constitutional unit derived from the hydroxyl-containing ethylenically unsaturated monomer (b) is preferably 35% by mass or more and 80% by mass or less with respect to the total amount of constitutional units derived from the ethylenically unsaturated monomer (c).

[0054] The resin may include a thermoplastic resin or a thermosetting resin in addition to a photosensitive acrylic resin.

[0055] As the colorant, a known pigment can be used as long as it does not impair the low-temperature characteristics (thermal curing at 150° C. or less) of the color filter of the present embodiment. For example, as inorganic pigments, metal oxide powders such as barium sulfate, zinc oxide, lead sulfate, yellow lead, cadmium red, ultramarine, chromium oxide green, titanium black, synthetic iron black, metal sulfide powders, etc. can be used. It is preferable to use it in combination with an organic pigment.

[0056] The experiment shown in Fig. 5 was carried out using a color filter 11 formed from the above-mentioned color filter material, and the thickness of the color filter 11 was adjusted to control the transmittance of the color filter as shown in Fig. 5. The thickness was adjusted so that the transmittance was 1.2 to 30% at a wavelength of 450 nm. Specifically, in this experiment, the thickness of the color filter 11 was adjusted within the range of 1.16 to 1.18 µm.

[0057] In this embodiment, in the above-mentioned characteristic point (1), the spectral transmittance is preferably 25% or less, more preferably 20% or less, even more preferably 10% or less, and even more preferably 5% or less.

[0058] FIG. 6 shows the emission spectrum (green) when the color filter 11 is laminated. FIG. 7 shows the emission spectrum (red) when the color filters are laminated. "No G-cut" and "No R-cut" in FIGS. 6 and 7 refer to a configuration in which a green filter and a red filter are not laminated. On the other hand, the other graph lines refer to a configuration in which each color filter described in FIG. 5 is laminated. As shown in FIGS. 6 and 7, it was found that by laminating the color filters of this embodiment having features (1) and (2), blue light (excitation light from the light-emitting element) can be effectively removed, and as a result, the color purity of green and red is improved.

[0059] 6 and 7, the removal rate of the excitation light varies depending on the transmittance of the color filter. From the experimental results, it was found that by setting the spectral transmittance of the color filter 11 at the emission peak wavelength of the light-emitting element 4 to 30% or less, the spectral irradiance of the excitation light can be suppressed to 10 or less, by setting it to 20% or less, the spectral irradiance of the excitation light can be reduced to approximately 8 or less, and by setting it to 10% or less, the spectral irradiance of the excitation light can be reduced to approximately 5 or less. 8 is a graph showing the relationship between the transmittance and chromaticity gamut of a color filter when the emission wavelength is 450 nm. The chromaticity gamut can be expressed in NTSC ratio.

[0060] As shown in Figure 8, it was found that the NTSC ratio can be increased to 65% or more by setting the transmittance of the color filter at an emission wavelength of 450 nm to 30% or less. It was also found that the NTSC ratio can be increased to 72% or more by setting the transmittance of the color filter at an emission wavelength of 450 nm to 20% or less. In this way, it was found that a good color reproduction range can be obtained at the NTSC ratio.

[0061] By setting the transmittance of the color filter at an emission wavelength of 450 nm to 20% or less, the NTSC ratio can be increased to 72% or more, thereby satisfying the color reproduction standard of the display device.

[0062] <Manufacturing Method of Display Device of This Embodiment> FIG. 9 is a schematic cross-sectional view showing a manufacturing process of the micro LED display of the present embodiment.

[0063] 9(a), a wafer with micro LEDs is prepared in which a plurality of light-emitting elements (LEDs) 4 are arranged on a substrate 3, and a barrier layer 5 is formed to separate the light-emitting elements 4. Here, the light-emitting elements 4 are preferably blue light-emitting elements. The method for forming the barrier layer 5 is not limited to a specific method, and may be an etching method, a lift-off method, or the like.

[0064] 9(b), the color conversion layers 6a and 6b are formed by filling the internal spaces 5b of the red display pixel 2a and the green display pixel 2b with a quantum dot-containing composition, among the internal spaces 5b partitioned by the partition layer 5. Here, it is preferable to use cadmium-free quantum dots, and for example, ZnSe or InP can be used.

[0065] The internal space 5b of the blue display pixel 2c is filled with a resin 9. The resin 9 is preferably a transparent resin.

[0066] Next, a barrier layer (not shown) made of SiO2 or the like is formed over the entire area on the color conversion layer and the transparent resin layer, and then a color filter 11 having a red filter 11a, a green filter 11b, and a blue filter 11c is formed. It is preferable to use a low-temperature curing color filter material for the color filter 11. A thermosetting material containing the above-mentioned colorant, photopolymerizable monomer, photopolymerization initiator, and resin can be used as the color filter material.

[0067] In this embodiment, the heat treatment temperature of the color filter material can be set to 150° C. or less. Preferably, the heat treatment temperature can be set to 130° C. or less.

[0068] Quantum dots are subject to deterioration such as oxidation when exposed to high temperatures. In this embodiment, it is essential that the color filter 11 is formed on the color conversion layers 6a and 6b containing quantum dots. In a normal color filter formation process, the high heat treatment temperature leads to deterioration of the quantum dots, but in this embodiment, by using a low-temperature curing color filter material, the color filter 11 can be formed without deteriorating the quantum dots.

[0069] As shown in FIG. 5, the spectrum of color filter 11 can be controlled, for example, by the thickness of color filter 11, so that the transmittance at the emission peak wavelength (450 nm) of the blue light-emitting element can be reduced and the transmittance at the fluorescence peak wavelength (green: 550 nm, red: 620 nm) of light wavelength-converted by the quantum dots can be increased, thereby obtaining excellent display characteristics.

[0070] The display device according to the present embodiment can be used not only indoors but also outdoors under high brightness. The display device according to the present embodiment can be applied to a micro LED display device, which enables miniaturization. [Explanation of symbols]

[0071] 1: Micro LED display 2a: Red display pixel 2b: Green display pixel 2c: Blue display pixel 3: Substrate 4: Light emitting element 5: Partition layer 6a, 6b: color conversion layer 7: Red quantum dots 8: Green quantum dots 10: Barrier layer 11: Color filter 11a: Red filter 11b: Green filter 11b: Red filter 11c: Blue filter 12a~12c: Micro lenses L1: Cyan light L2: Green light L3 : Red Light

Claims

1. A plurality of light emitting elements disposed on a substrate; A color conversion layer disposed on the light-emitting element; a color filter disposed on the color conversion layer; a plurality of display pixels comprising: the spectral transmittance of the color filter at the emission peak wavelength of the light-emitting element is 30% or less; the spectral transmittance of the color filter at the peak wavelength of fluorescence transmitted through the color conversion layer is 80% or more; A display device comprising:

2. 2. The display device according to claim 1, further comprising a partition layer formed between adjacent ones of the color conversion layers.

3. The display device according to claim 1 , wherein the color conversion layer includes quantum dots.

4. 4. The display device of claim 3, wherein the quantum dots are cadmium-free.

5. a display pixel having blue, red and green colors; 2. The display device according to claim 1, wherein the red and green display pixels are formed of a laminated structure of the light emitting element, the color conversion layer, and the color filter.

6. 2. The display device according to claim 1, wherein the light-emitting element is a blue light-emitting element.

7. 2. The display device according to claim 1, wherein a microlens is formed on the color filter.

8. 2. The display device according to claim 1, wherein the NTSC ratio is 65% or more.

9. A method for manufacturing a display device according to claim 1, comprising the steps of: The method for producing a display device comprises forming the color filter at a heat treatment temperature of 150° C. or less.

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