Display device

Abstract

A display device capable of more efficiently extracting, to the outside, light having transmitted a wavelength conversion layer is provided. The provided display device comprises: a light source which is provided in each of a first pixel and a second pixel, and which emits light of a first wavelength; a first wavelength conversion layer which is formed in the first pixel and which converts the light of the first wavelength into light of a second wavelength; a second wavelength conversion layer which is formed in the second pixel and converts the light of the first wavelength into light of a third wavelength that differs from the second wavelength; a first color filter, which is provided in the first pixel and selectively transmits the light of the second wavelength; a second color filter, which is provided in the second pixel and selectively transmits the light of the third wavelength; and at least a plurality of nanomembers on which the light of the second wavelength and the light of the third wavelength are incident, wherein: the plurality of nanomembers include a high refractive index dielectric material; and the plurality of nanomembers are arranged in the first pixel at a first period, and the plurality of nanomembers are arranged in the second pixel at a second period that differs from the first period.

Description

display device

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

[0002] Recently, the development of display devices with wavelength conversion layers has been in progress. In these display devices, the wavelength of light emitted from a light source is converted in the wavelength conversion layer and then output to the outside.

[0003] Additionally, a method for increasing light utilization efficiency by using multiple nano members has been proposed.

[0004] The above information may be provided as background art to aid in understanding the present disclosure. No claim or determination is made as to whether any of the above is applicable as prior art in connection with the present disclosure.

[0005] In a display device having a wavelength conversion layer, it is desirable to more efficiently extract light transmitted through the wavelength conversion layer to the outside.

[0006] One aspect of the present disclosure is to address at least the aforementioned problems and / or disadvantages and provide at least the advantages described below. Therefore, according to one aspect of the present disclosure, a display device capable of more efficiently extracting light transmitted through a wavelength conversion layer to the outside can be provided.

[0007] Additional aspects will be partly set forth in the following description, and partly will become apparent from the description or may be learned by practicing the embodiments provided.

[0008] According to one aspect of the present disclosure, a display device includes at least a light source provided to each of a first pixel and a second pixel and emitting light of a first wavelength, a first wavelength conversion layer formed in the first pixel and converting light of the first wavelength into light of a second wavelength, a second wavelength conversion layer formed in the second pixel and converting light of the first wavelength into light of a third wavelength different from the second wavelength, a first color filter provided in the first pixel and selectively transmitting light of the second wavelength, a second color filter provided in the second pixel and selectively transmitting light of the third wavelength, and a plurality of nano-elements on which light of the second wavelength and light of the third wavelength are incident, wherein the plurality of nano-elements include a high refractive index dielectric, and the plurality of nano-elements are arranged in a first period in the first pixel, and the plurality of nano-elements are arranged in the second pixel and the first period in the second pixel. It may be a display device arranged in a second cycle different from the first cycle.

[0009] According to one embodiment of the present disclosure, the display device may further have an overcoat layer formed between the first color filter and the first wavelength conversion layer, and between the second color filter and the second wavelength conversion layer, and the plurality of nano-members may be provided between the overcoat layer and each of the first wavelength conversion layer and the second wavelength conversion layer.

[0010] According to one embodiment of the present disclosure, the display device may be a display device in which the light source is further provided to a third pixel, and the plurality of nano-elements are arranged in the third pixel in a third period different from the first period and the second period.

[0011] According to one embodiment of the present disclosure, the display device may be a display device in which the light of the second wavelength is light in a red wavelength range and the light of the third wavelength is light in a green wavelength range.

[0012] According to one embodiment of the present disclosure, the display device may be a display device in which the first period is longer than the second period and the second period is longer than the third period.

[0013] According to one embodiment of the present disclosure, the display device may be a display device in which the first period is 500 nm or more and 700 nm or less, the second period is 450 nm or more and 500 nm or less, and the third period is 350 nm or more and 430 nm or less.

[0014] According to one embodiment of the present disclosure, the display device may be a display device in which the plurality of nano-elements arranged in the first cycle resonate with light of the second wavelength, and the plurality of nano-elements arranged in the second cycle resonate with light of the third wavelength.

[0015] According to one embodiment of the present disclosure, the display device is a display device according to any one of (1) to (7), wherein the plurality of nano-materials have a refractive index of 2.0 or more.

[0016] According to one embodiment of the present disclosure, the display device may be a display device in which the plurality of nano-materials include at least one of titanium oxide (TiO2) and silicon (Si).

[0017] According to one embodiment of the present disclosure, the display device may be a display device in which the plurality of nano-members have a columnar, cone-shaped, hemispherical or cap-shaped shape.

[0018] According to one embodiment of the present disclosure, the display device may be a display device in which the first wavelength conversion layer and the second wavelength conversion layer each include a plurality of nanoparticles.

[0019] According to one embodiment of the present disclosure, the display device may be a display device in which each of the plurality of nanoparticles includes at least one of silver (Ag) and aluminum (Al).

[0020] According to one embodiment of the present disclosure, the display device may be a display device in which the light source includes a micro LED (Light Emitting Diode).

[0021] According to one embodiment of the present disclosure, the display device may be a display device in which the light of the first wavelength is light in the blue wavelength range.

[0022] According to one embodiment of the present disclosure, the display device may be a display device in which the first wavelength conversion layer and the second wavelength conversion layer each include at least one of a quantum dot and a fluorescent substance.

[0023] According to one embodiment of the present disclosure, the display device may further have an overcoat layer formed between the first color filter and the first wavelength conversion layer and between the second color filter and the second wavelength conversion layer, and a transparent substrate facing the overcoat layer with the first color filter and the second color filter interposed therebetween, and the plurality of nano-members may be a display device provided between the transparent substrate and the first color filter and the second color filter.

[0024] According to one embodiment of the present disclosure, the display device may be a display device in which the overcoat layer has a refractive index of 1.3 or less.

[0025] According to one embodiment of the present disclosure, the display device may further include a first dichroic filter provided between the first wavelength conversion layer and the first color filter, transmitting light of the second wavelength while reflecting light of the first wavelength, and a second dichroic filter provided between the second wavelength conversion layer and the second color filter, transmitting light of the third wavelength while reflecting light of the first wavelength.

[0026] In a display device according to one embodiment of the present invention, a plurality of nano-elements are arranged in a first period in a first pixel, and a plurality of nano-elements are arranged in a second period in a second pixel.

[0027] In one embodiment, a plurality of nano-elements are arranged in a cycle corresponding to light of a second wavelength and light of a third wavelength, respectively. Accordingly, light of the second wavelength and light of the third wavelength are efficiently extracted from the display device. Accordingly, light transmitted through the wavelength conversion layer is more efficiently extracted to the outside.

[0028] Other aspects, advantages and important features of the present disclosure will become apparent to those skilled in the art from the following detailed description of various embodiments of the present disclosure taken in conjunction with the accompanying drawings.

[0029] The above-described aspects or other aspects, configurations and / or advantages of one embodiment of the present disclosure may be further clarified by the following detailed description taken in conjunction with the accompanying drawings.

[0030] FIG. 1 is a cross-sectional view showing one embodiment of a display device configuration according to one embodiment of the present disclosure.

[0031] FIG. 2A is a diagram showing a planar configuration of the red conversion layer and nano-materials illustrated in FIG. 1, according to one embodiment of the present disclosure.

[0032] FIG. 2B is a drawing showing a cross-sectional configuration along line BB shown in FIG. 2A, according to one embodiment of the present disclosure.

[0033] FIG. 3A is a cross-sectional view illustrating another example of the nano-material configuration illustrated in FIG. 2B, according to one embodiment of the present disclosure.

[0034] FIG. 3B is a cross-sectional view illustrating another example of the nano-material configuration illustrated in FIG. 2B, according to one embodiment of the present disclosure.

[0035] FIG. 3C is a cross-sectional view showing another example of the nano-material configuration illustrated in FIG. 2B, according to one embodiment of the present disclosure.

[0036] FIG. 3D is a cross-sectional view illustrating another example of the nano-material configuration illustrated in FIG. 2B, according to one embodiment of the present disclosure.

[0037] FIG. 4A is a cross-sectional view showing the red conversion layer configuration illustrated in FIG. 1, according to one embodiment of the present disclosure.

[0038] FIG. 4B is a cross-sectional view showing the green conversion layer configuration illustrated in FIG. 1, according to one embodiment of the present disclosure.

[0039] FIG. 5A is a cross-sectional view showing step 1 of a method for manufacturing a display device illustrated in FIG. 1, according to one embodiment of the present disclosure.

[0040] FIG. 5B is a cross-sectional view showing a process subsequent to FIG. 5A, according to one embodiment of the present disclosure.

[0041] Figure 6A is a drawing for explaining light extracted from a display device according to a comparative example.

[0042] FIG. 6B is a drawing for explaining light extracted from the display device illustrated in FIG. 1, according to one embodiment of the present disclosure.

[0043] FIG. 7 is a cross-sectional view showing a red pixel configuration of a display device according to one embodiment of the present disclosure.

[0044] FIG. 8 is a cross-sectional view showing a red pixel configuration of a display device according to Variation 1, according to one embodiment of the present disclosure.

[0045] Throughout the attached drawings, similar reference numbers may be assigned to similar parts, components and / or structures.

[0046] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. In the drawings below, like reference numerals designate like components, and the sizes of each component in the drawings may be exaggerated for clarity and convenience of explanation.

[0047] The following description of the accompanying drawings may provide an understanding of various exemplary implementations of the present disclosure, including the claims and their equivalents. While the exemplary embodiments disclosed in the following description include numerous specific details to aid understanding, they are to be considered as one example of various exemplary embodiments. Accordingly, those skilled in the art will appreciate that various modifications and variations of the various implementations described in this disclosure may be made without departing from the scope and spirit of the disclosure. Furthermore, descriptions of well-known functions and configurations may be omitted for clarity and conciseness.

[0048] The terms and words used in the following description and claims are not limited to their reference meanings and can be used to clearly and consistently describe one embodiment of the present disclosure. Therefore, it will be apparent to those skilled in the art that the following description of various implementations of the disclosure is provided for illustrative purposes, not for the purpose of limiting the scope of the disclosure and its equivalents.

[0049] Unless the context clearly dictates otherwise, the singular forms of "a," "an," and "the" should be understood to include plural meanings. Thus, for example, "a component surface" could be understood to include one or more of the surfaces of the component.

[0050] Hereinafter, the terms "upper" or "upper" may include not only things directly above in contact, but also things above in non-contact. Furthermore, the terms "lower" or "lower" may include not only things directly below in contact, but also things below in non-contact.

[0051] Additionally, when a part is said to "include," "have," or "contain" a component, this means that it may include other components, but not to the exclusion of other components, unless specifically stated otherwise.

[0052] Unless the order of steps in a method is clearly described or otherwise stated to the contrary, the steps may be performed in any appropriate order. The order of the steps described above is not necessarily limited. Any use of examples or terminology is solely for the purpose of illustrating technical concepts and is not intended to limit the scope of the invention unless otherwise defined by the claims.

[0053] It should be noted that each block of a flowchart and its combination can be executed by one or more computer programs containing instructions. The entirety of one or more computer programs may be stored in a single memory device, or the one or more computer programs may be divided into different parts stored in different memory devices.

[0054] The functions or operations described herein may be performed by a single processor or a combination of processors. A single processor or a combination of processors is a circuit that performs processing and includes an application processor (AP, e.g., a central processing unit (CPU)), a communications processor (CP, e.g., a modem), a graphics processing unit (GPU), a neural processing unit (NPU) (e.g., an artificial intelligence (AI) chip), a Wi-Fi chip, a Bluetooth® chip, a global positioning system (GPS) chip, a near-field communication (NFC) chip, a connection chip, a sensor controller, a touch controller, a fingerprint sensor controller, a display driver integrated circuit (IC), an audio codec chip, a universal serial bus (USB) controller, a camera controller, an image processing IC, a microprocessor unit (MPU), a system on a chip (SoC), an IC, or similar circuits.

[0055] In addition, in the following description, when ordinal numbers such as “first” and “second” are used for explanation, unless specifically stated, they are used for convenience and do not specify any order.

[0056] [Example 1]

[0057] FIG. 1 illustrates an example of a cross-sectional configuration of a display device according to one embodiment of the present disclosure.

[0058] Referring to FIG. 1, the display device (100) may include a first structure (110), a second structure (120), and a joint (130). In the display device (100), for example, the second structure (120) and the first structure (110) may be laminated, and a joint (130) may be formed between them. The second structure (120) may include a light source (122). Light emitted from the light source (122) may sequentially pass through the joint (130) and the first structure (110) and be extracted to the outside of the display device (100). The light source (122) may emit light in a blue wavelength range (e.g., 430 nm to 495 nm), for example. The light source (122) may emit light in another wavelength range, such as ultraviolet light.

[0059] In this display device (100), a plurality of red pixels (10r), a plurality of green pixels (10g), and a plurality of blue pixels (10b) can be arranged in a matrix shape. Light in a red wavelength range (e.g., 600 nm to 750 nm) can be extracted from the red pixel (10r), light in a green wavelength range (e.g., 495 nm to 570 nm) can be extracted from the green pixel (10g), and light in a blue wavelength range can be extracted from the blue pixel (10b). In the following description, the stacking direction of the second structure (120) and the first structure (110) can be referred to as the Z direction, and the arrangement directions of the red pixel (10r), the green pixel (10g), and the blue pixel (10b) can be referred to as the X direction and the Y direction.

[0060] <Configuration of display device (100)>

[0061] (1st structure (110))

[0062] The first structure (110) may include, for example, a transparent substrate (111), a light-shielding matrix (112), a color filter (113), an overcoat layer (114), a nano-material (115) which is a high refractive index dielectric, a partition wall (116), a color conversion layer (117), and a transparent layer (118). The color filter (113) may include, for example, a red color filter (113r), a green color filter (113g), and a blue color filter (113b). The color conversion layer (117) may include, for example, a red conversion layer (117r) and a green conversion layer (117g).

[0063] In the red pixel (10r), a transparent substrate (111), a red color filter (113r), an overcoat layer (114), a nano-material (115), and a red conversion layer (117r) may be arranged in this order along the Z direction. In the green pixel (10g), a transparent substrate (111), a green color filter (113g), an overcoat layer (114), a nano-material (115), and a green conversion layer (117g) may be arranged in this order along the Z direction. In the blue pixel (10b), a transparent substrate (111), a blue color filter (113b), an overcoat layer (114), a nano-material (115), and a transparent layer (118) may be arranged in this order along the Z direction.

[0064] The transparent substrate (111) may be, for example, a plate-shaped member having a rectangular plane (XY plane) shape. The transparent substrate (111) may have light transparency. The transparent substrate (111) may include, for example, a glass material, a resin material, or the like. The resin material may be, for example, polyimide, or the like. The transparent substrate (111) may have flexibility.

[0065] The light-shielding matrix (112) may be a so-called black matrix. The light-shielding matrix (112) may be provided, for example, between one main surface of the transparent substrate (111) and the overcoat layer (114) together with the color filter (113). The light-shielding matrix (112) may serve to prevent color mixing of light emitted from the red pixel (10r), the green pixel (10g), and the blue pixel (10b), respectively. The light-shielding matrix (112) may be provided, for example, between the red color filter (113r) and the green color filter (113g), between the green color filter (113g) and the blue color filter (113b), and between the blue color filter (113b) and the red color filter (113r). An end of the light-shielding matrix (112) may overlap an end of the color filter (113). The shading matrix (112) may be composed of a patternable shading material.

[0066] The color filter (113) can selectively transmit light of a predetermined wavelength range. According to one embodiment, the red color filter (113r) can selectively transmit light of a red wavelength range. The green color filter (113g) can selectively transmit light of a green wavelength range. The blue color filter (113b) can selectively transmit light of a blue wavelength range. By providing such a color filter (113), the color purity of light extracted from each of the red pixel (10r), the green pixel (10g), and the blue pixel (10b) can be increased. The color filter (113) can include, for example, a resin material.

[0067] An overcoat layer (114) may be formed between the color filter (113) and the nano-material (115) and between the light-shielding matrix (112) and the partition wall (116). The overcoat layer (114) may serve to planarize the main surface of the transparent substrate (111) on which the light-shielding matrix (112) and the color filter (113) are provided, and to protect the color filter (113). The overcoat layer (114) may include, for example, a photosensitive acrylic resin. The refractive index of the overcoat layer (114) may be, for example, about 1.5.

[0068] A plurality of nano-members (115) may be provided for each of the red pixel (10r), the green pixel (10g), and the blue pixel (10b). In the red pixel (10r), a plurality of nano-members (115) may be provided between the red color filter (113r) and the red conversion layer (117r). In the green pixel (10g), a plurality of nano-members (115) may be provided between the green color filter (113g) and the green conversion layer (117g). In the blue pixel (10b), a plurality of nano-members (115) may be provided between the blue color filter (113b) and the transparent layer (118).

[0069] The nanomaterial (115) may include a high refractive index dielectric. The high refractive index dielectric may be, for example, a material having a refractive index of 2.0 or higher. The high refractive index dielectric may be, for example, titanium oxide (TiO2), zinc oxide (ZnO), zirconium oxide (ZrO2), or silicon (Si). For example, the refractive index at a wavelength of 600 nm is 2.5 for titanium oxide, 2.0 for zinc oxide, 2.1 for zirconium oxide, and 4.2 for silicon. The nanomaterial (115) may include at least one of titanium oxide and silicon. The nanomaterial (115) may include, for example, a resin material and nanoparticles of the high refractive index dielectric dispersed in the resin material. The nanomaterial (115) may be composed of a high refractive index dielectric.

[0070] FIGS. 2A and 2B illustrate a configuration of a plurality of nano-elements (115) provided in a red pixel together with a red conversion layer, according to various embodiments of the present disclosure.

[0071] Figure 2A shows the arrangement of multiple nano-members in the XY plane, and Figure 2B shows a cross-sectional configuration along the line BB shown in Figure 2A.

[0072] According to FIGS. 2A and 2B, the nano-member (115) may be, for example, in a cylindrical shape. The height direction of the cylinder may be arranged parallel to the Z direction. The diameter (D) of the nano-member (115) may be, for example, 300 nm to 450 nm in the red pixel (10r), 250 nm to 350 nm in the green pixel (10g), and 200 nm to 300 nm in the blue pixel (10b). The height (H) of the nano-member (115) may be 150 nm to 300 nm. A plurality of nano-members (115) may be regularly arranged in each of, for example, the red pixel (10r), the green pixel (10g), and the blue pixel (10b). In the red pixel (10r), the green pixel (10g), and the blue pixel (10b), for example, a plurality of nano-elements (115) can be arranged in a triangular lattice shape.

[0073] When light of a visible wavelength is incident on these multiple nano-elements (115), Mie resonance occurs, and a light localization phenomenon may occur near each nano-element (115). The localized light may be emitted by causing a diffraction phenomenon due to the periodic arrangement of the nano-elements (115). Therefore, the direction of propagation of light can be changed by the multiple nano-elements (115). Specifically, the relationship between the incident light and the diffracted light in the multiple nano-elements (115) can be expressed by the following mathematical expression 1.

[0074]

[0075] In equation (1),

[0076] is the wave vector of the diffracted light,

[0077] is the wave vector of the incident light,

[0078] represents the grid vector.

[0079] It depends on the shape of the nano-material (115), the wavelength of light incident on the nano-material (115), and the incident angle of the nano-material (115). may depend on the cycle of placing multiple nano-elements (115).

[0080] In one embodiment, the period may refer to a distance between nano-elements (115) that are periodically repeated. For example, the period may be a distance between adjacent red pixels (10r) among a plurality of red pixels (10r), a distance between adjacent green pixels (10g) among a plurality of green pixels (10g), or a distance between adjacent blue pixels (10b) among a plurality of blue pixels (10b).

[0081] According to one embodiment, the arrangement cycles of the plurality of nano-elements (115) may be different among the red pixel (10r), the green pixel (10g), and the blue pixel (10b). According to one embodiment, the cycles of the plurality of nano-elements (115) may be adjusted according to the wavelengths of light extracted from each of the red pixel (10r), the green pixel (10g), and the blue pixel (10b). For example, the plurality of nano-elements (115) are arranged with a cycle Pr in the red pixel (10r), a cycle Pg in the green pixel (10g), and a cycle Pb in the blue pixel (10b).

[0082] By means of a plurality of nano-elements (115) arranged with a period Pr, grating-coupled resonance can be generated in light in the red wavelength region. By means of a plurality of nano-elements (115) arranged with a period Pg, grating-coupled resonance can be generated in light in the green wavelength region. By means of a plurality of nano-elements (115) arranged with a period Pb, grating-coupled resonance can be generated in light in the blue wavelength region. By means of the grating-coupled resonance, an optical localization phenomenon occurs in the vicinity of each of the plurality of nano-elements (115), and the directivity of light extracted from each of the red pixel (10r), the green pixel (10g), and the blue pixel (10b) can be increased. As described in detail later, due to this, light in each of the red wavelength region, the green wavelength region, and the blue wavelength region can be efficiently extracted from the display device (100) to the outside.

[0083] For example, the longer the wavelength of light emitted from a pixel, the longer the period of the plurality of nano-elements (115). For example, the period Pr is longer than the period Pg, and the period Pg is longer than the period Pb. That is, the periods Pr, Pg, and Pb can satisfy the following mathematical expression 2.

[0084]

[0085] The period Pr may be, for example, 500 nm or more and 700 nm or less, the period Pg may be, for example, 450 nm or more and 500 nm or less, and the period Pb may be, for example, 350 nm or more and 430 nm or less.

[0086] The periods Pr, Pg, and Pb of the nano-material (115) and the resonance wavelength (scattering wavelength) by the nano-material (115) may have, for example, the following relationship. At this time, the diameter (D) of the cylindrical nano-material (115) is 400 nm, the height (H) is 300 nm, and the nano-material (115) may be arranged in a triangular lattice shape. The nano-material (115) may include silicon. For example, when the periods Pr are 550 nm, 580 nm, and 600 nm, the resonance wavelengths of the nano-material (115) are 600 nm, 630 nm, and 650 nm. When the periods Pg are 450 nm, 480 nm, and 500 nm, the resonance wavelengths of the nano-material (115) may be 500 nm, 530 nm, and 550 nm. When the period Pb is 350 nm, 400 nm, and 430 nm, the resonance wavelength of the nano member (115) can be 400 nm, 430 nm, and 480 nm.

[0087] FIGS. 3A, 3B, 3C, and 3D illustrate other examples of the nano-member illustrated in FIG. 2B, according to various embodiments of the present disclosure. The nano-member (115) may have a hemispherical shape (FIGS. 3A and 3D). In this case, the plane of the hemisphere may be arranged toward the red conversion layer (117r) (FIG. 3A), or the spherical surface of the hemisphere may be arranged toward the red conversion layer (117r) (FIG. 3B). The nano-member (115) may have a cap shape (FIG. 3B). Alternatively, the nano-member (115) may have a conical shape, such as a cone, a triangular pyramid, or a square pyramid. The nano-member (115) may have a cylindrical shape other than a cylinder, and may have shapes such as, for example, a triangular prism and a square prism (not illustrated).

[0088] The partition wall (116) can partition a red pixel (10r), a green pixel (10g), and a blue pixel (10b). The height (size in the Z direction) of the partition wall (116) can be approximately the same as the thickness of the red conversion layer (117r), the green conversion layer (117g), and the transparent layer (118). The height of the partition wall (116) can be, for example, 5 μm or more and 50 μm or less. The partition wall (116) can have a light reflection characteristic for light in a wavelength range emitted from the light source (122) and light in a wavelength range converted in the red conversion layer (117r) and the green conversion layer (117g). Therefore, light directly from the light source (122) or light that passes through the red conversion layer (117r) and the green conversion layer (117g) from the light source (122) and heads toward the partition wall (116) can be reflected by the partition wall (116). Accordingly, the utilization efficiency of light emitted from the light source (122) is increased, thereby improving the light extraction efficiency. The partition wall (116) may include, for example, a white pigment and a resin material. The resin material may be, for example, a photosensitive resin material such as an acrylic resin, an epoxy resin, a silicone resin, or a polyimide resin.

[0089] The color conversion layer (117) formed on the red pixel (10r) and the green pixel (10g) can convert the wavelength of light incident from the second structure (120) side and transmit it to the plurality of nano-members (115) side.

[0090] FIG. 4A illustrates a configuration of a red conversion layer (117r) according to one embodiment of the present disclosure.

[0091] FIG. 4B illustrates one embodiment of a green conversion layer (117g) configuration according to one embodiment of the present disclosure.

[0092] Referring to FIGS. 4A and 4B, the red conversion layer (117r) formed in the red pixel (10r) may include, for example, a wavelength conversion material (1171r), nanoparticles (1172), and a binder (1173). The green conversion layer (117g) formed in the green pixel (10g) may include, for example, a wavelength conversion material (1171g), nanoparticles (1172), and a binder (1173).

[0093] The wavelength conversion material (1171r, 1171g) may include, for example, a fluorescent substance or a quantum dot. According to one embodiment, the red conversion layer (117r) and the green conversion layer (117g) may include at least one of a fluorescent substance and a quantum dot. The wavelength conversion material (1171r) may convert the wavelength of light emitted from the light source (122) into a red wavelength range. The wavelength conversion material (1171g) may convert the wavelength of light emitted from the light source (122) into a green wavelength range.

[0094] In the red conversion layer (117r) and the green conversion layer (117g), a plurality of nanoparticles (1172) may be dispersed in a binder (1173). The nanoparticles (1172) may be configured to enable plasmon absorption of light emitted from a light source (122). The nanoparticles (1172) may include, for example, a metal material. The nanoparticles (1172) may include, for example, at least one of silver (Ag) and aluminum (Al). The nanoparticles (1172) may be, for example, spherical. The particle size (diameter) of the nanoparticles (1172) may be, for example, 60 nm or more and 100 nm or less. For example, the resonance wavelength of the nanoparticles (1172) overlaps with the wavelength of the light emitted from the light source (122). For example, in nanoparticles (1172) containing silver and having a spherical shape, the resonance wavelength (absorption wavelength) is 410 nm when the particle size is 60 nm, 430 nm when the particle size is 70 nm, 450 nm when the particle size is 80 nm, 470 nm when the particle size is 90 nm, and 490 nm when the particle size is 100 nm.

[0095] In the red conversion layer (117r) and the green conversion layer (117g) including such nanoparticles (1172), the wavelength conversion efficiency of light emitted from the light source (122) can be improved. According to one embodiment, when light emitted from the light source (122) is incident on the red conversion layer (117r) and the green conversion layer (117g), the light may be absorbed by plasmons in the nanoparticles (1172) to generate an augmented electric field. By the augmented electric field acting on the wavelength conversion material (1171r, 1171g), the wavelength of the light emitted from the light source (122) can be converted more efficiently. That is, light in the red wavelength region and light in the green wavelength region can be extracted more efficiently from the red conversion layer (117r) and the green conversion layer (117g).

[0096] The binder in which the wavelength conversion material (1171r, 1171g) and nanoparticles (1172) are dispersed may include a resin material such as a silicone resin, an epoxy resin, or an acrylic resin, for example.

[0097] The transparent layer (118) formed on the blue pixel (10b) can transmit light emitted from the light source (122) toward the transparent substrate (111) with high transmittance. The transparent layer (118) can transmit light emitted from the light source (122) with, for example, a transmittance of 70% or more. The transparent layer (118) can include, for example, a resin material.

[0098] (Second structure (120))

[0099] The second structure (120) may include, for example, a TFT (Thin Film Transistor) substrate (121), a light source (122), and an anisotropic conductive film (123).

[0100] The TFT substrate (121) may be arranged opposite to the transparent substrate (111) in the Z direction. The TFT substrate (121) is a substrate for driving a light source (122), and may include, for example, a substrate, a wiring layer formed on the substrate, and a TFT. Instead of a TFT, the wiring layer may have another driving element. Alternatively, the display device (100) may be a passive matrix drive.

[0101] A plurality of light sources (122) may be provided on the TFT substrate (121). The light sources (122) may be provided to each of the red pixel (10r), the green pixel (10g), and the blue pixel (10b). The light sources (122) may include, for example, micro LEDs. The light sources (122) may have, for example, a rectangular planar (XY plane) shape. The size of one side of the square may be, for example, 1 μm or more and 100 μm or less. The light sources (122) may have a three-dimensional shape, for example, an approximately rectangular parallelepiped or an approximately cube. The light sources (122) may include, for example, a gallium nitride (GaN)-based semiconductor material, and may emit light in the ultraviolet to blue wavelength range. An anisotropic conductive film (123) can be formed on a TFT substrate (121) together with a plurality of light sources (122).

[0102] (Joint (130))

[0103] A joint (130) formed between the first structure (110) and the second structure (120) can join the first structure (110) and the second structure (120). The thickness (size in the Z direction) of the joint (130) can be, for example, 5 μm or less. The joint (130) can include an adhesive, a glue, or the like. The joint (130) can include, for example, a transparent epoxy resin, a silicone resin, or the like.

[0104] <Method for manufacturing display device (100)>

[0105] Next, a method for manufacturing a display device (100) will be described.

[0106] The first structure (110) can be manufactured, for example, as described below. According to one embodiment, a light-shielding matrix (112) and a color filter (113) can be sequentially formed on a transparent substrate (111). In forming the color filter (113), a red color filter (113r) can be formed on a red pixel (10r), a green color filter (113g) on ​​a green pixel (10g), and a blue color filter (113b) on a blue pixel (10b), respectively. In addition, an overcoat layer (114) can be formed on the transparent substrate (111) so as to cover the light-shielding matrix (112) and the color filter (113). In addition, a plurality of nano-members (115) can be formed on the overcoat layer (114).

[0107] FIG. 5A and FIG. 5B illustrate a method of forming a plurality of nano-members (115), according to one embodiment of the present disclosure.

[0108] Referring to FIGS. 5A and 5B, a plurality of nano-members (115) can be formed, for example, as described below. According to one embodiment, a resin (1151) containing nano-particles (1152) can be applied onto an overcoat layer (114) (FIG. 5A). The resin (1151) can include, for example, a light-transmitting UV (Ultraviolet) resin. The nano-particles (1152) can be composed of, for example, nano-particles of titanium oxide or silicon. According to one embodiment, a plurality of nano-members (115) can be formed using a nanoimprint method (FIG. 5B). A nanoimprint mold (200) having a predetermined pattern is provided on a resin (1151) containing nanoparticles (1152), and by irradiating ultraviolet light (Luv), a plurality of nano-members (115) can be formed, each with a period Pr for a red pixel (10r), a period Pg for a green pixel (10g), and a period Pb for a blue pixel (10b).

[0109] According to one embodiment, a partition wall (116) can be formed on an overcoat layer (114) using a photolithography process. In addition, a color conversion layer (117) and a transparent layer (118) can be formed in the area surrounded by the partition wall (116). As a result, a first structure (110) can be formed.

[0110] The second structure (120) can be manufactured, for example, as described below. According to one embodiment, a TFT substrate (121) can be formed. In addition, a light source (122) and an anisotropic conductive film (123) can be formed on the TFT substrate (121).

[0111] After forming the first structure (110) and the second structure (120), the first structure (110) and the second structure (120) can be joined as described below. According to one embodiment, a joining material to form a joining portion (130) can be applied on the second structure (120). In addition, the first structure (110) can be positioned on the surface of the second structure (120) on which the joining material has been applied so as to overlap. In addition, pressure can be applied in a direction that brings the first structure (110) and the second structure (120) closer under reduced pressure, and the joining material can be hardened by applying energy such as heat or ultraviolet rays to form the joining portion (130). For example, a full-color display display device (100) can be manufactured in this manner.

[0112] <Operation effect of display device (100)>

[0113] In the display device (100), light in the blue wavelength range, for example, can be emitted from a light source (122) provided to each of a red pixel (10r), a green pixel (10g), and a blue pixel (10b) and transmitted through a junction (130). In the red pixel (10r), light transmitted through the junction (130) can be incident on a red conversion layer (117r) and converted into light in the red wavelength range. The light in the red wavelength range can be diffracted by a plurality of nano-members (115) arranged with a period Pr, and sequentially transmitted through an overcoat layer (114), a red color filter (113r), and a transparent substrate (111).

[0114] In the green pixel (10g), light transmitted through the junction (130) can be incident on the green conversion layer (117g) and converted into light in the green wavelength range. The light in the green wavelength range can be diffracted by a plurality of nano-members (115) arranged with a period Pg, and sequentially transmitted through the overcoat layer (114), the green color filter (113g), and the transparent substrate (111).

[0115] In the blue pixel (10b), light emitted from the light source (122) can be diffracted by a plurality of nano-members (115) arranged in a period Pb after passing through the junction (130) and the transparent layer (118). The diffracted light can sequentially pass through the overcoat layer (114), the blue color filter (113b), and the transparent substrate (111).

[0116] According to one embodiment, in a display device (100), a plurality of nano-members (115) may be arranged with different periods (periods Pr, Pg, Pb) in a red pixel (10r), a green pixel (10g), and a blue pixel (10b). According to one embodiment, nano-members (115) with periods Pr, Pg, and Pb that are suited to light in the red wavelength region, the green wavelength region, and the blue wavelength region, respectively, may be arranged. Therefore, light in the red wavelength region, the green wavelength region, and the blue wavelength region, respectively, can be efficiently extracted from the display device (100) to the outside. Hereinafter, the above-described operational effects will be described using comparative examples.

[0117] Figure 6A shows the main configuration of a display device according to a comparative example.

[0118] Figure 6B shows the main configuration of a display device according to one embodiment.

[0119] Referring to FIGS. 6A and 6B, a display device (1000) according to a comparative example may not be provided with a nano-material (e.g., a nano-material (115) of FIG. 1). In the display device (1000), since the light (Lr) from the red conversion layer (117r) propagates isotropically, when extracted from the transparent substrate, loss of the light (Lr) due to Fresnel reflection may occur. For example, light (Lr) incident on the transparent substrate at an angle of 41.8 degrees or more may be totally reflected and not extracted to the outside of the display device (1000). The same applies to light from the green conversion layer and the transparent layer.

[0120] According to one embodiment, since the display device (100) is provided with a plurality of nano-elements (115), a light localization phenomenon due to a resonance may occur near the nano-elements (115) in light (Lr) from the red conversion layer (117r). Correspondingly, light localization may also occur near the nano-elements (115) in light from the green conversion layer (117g) and light from the transparent layer (118). As a result, the direction of propagation of the light may change. As shown in the above equation (1), the wave vector of the diffracted light may be expressed using a grating vector. The grating vector may depend on the arrangement period of the nano-elements (115).

[0121] A plurality of nano-elements (115) arranged with a period Pr in a red pixel (10r) can improve the directivity of light in a red wavelength region. A plurality of nano-elements (115) arranged with a period Pg in a green pixel (10g) can improve the directivity of light in a green wavelength region. A plurality of nano-elements (115) arranged with a period Pb in a blue pixel (10b) can improve the directivity of light in a blue wavelength region. Therefore, the directivity of light in each wavelength region extracted from each of the red pixel (10r), the green pixel (10g), and the blue pixel (10b) is improved, thereby suppressing light loss due to Fresnel reflection. In addition, in the display device (100), light transmitted through each of the red conversion layer (117r), the green conversion layer (117g), and the transparent layer (118) can be extracted to the outside more efficiently. For example, compared to the display device (1000), light with an intensity of about 2.8 times can be extracted from the red pixel (10r) and the green pixel (10g), and light with an intensity of about 2.0 times can be extracted from the blue pixel (10b).

[0122] According to one embodiment, in the display device (100), since the red conversion layer (117r) and the green conversion layer (117g) each include a plurality of nanoparticles (1172), light emitted from the light source (122) can be more efficiently converted into light in the red wavelength range and light in the green wavelength range. For example, compared to a red conversion layer and a green conversion layer that do not contain nanoparticles, light having an intensity of about 1.4 times greater can be extracted. In addition, since the red conversion layer (117r) and the green conversion layer (117g) each include a plurality of nanoparticles (1172), wavelength conversion can be efficiently performed even if the concentration of the wavelength conversion material (1171r, 1171g) is low. Therefore, the cost of the wavelength conversion material (1171r, 1171g) can be suppressed.

[0123] Hereinafter, other embodiments and modified examples of the display device (100) described in the first embodiment will be described. In addition, in order to avoid duplication of explanation, detailed descriptions of the same components as those of the display device (100) described in the first embodiment will be omitted.

[0124] [Example 2]

[0125] FIG. 7 illustrates a red pixel configuration of a display device, according to one embodiment.

[0126] Referring to Fig. 7, in the red pixel (10r) of the display device (100A), a plurality of nano-members (115) may be provided between the transparent substrate (111) and the red color filter (113r). In addition, the display device (100A) may have a configuration corresponding to the display device (100) of the first embodiment.

[0127] Between the transparent substrate (111) and the red color filter (113r), a plurality of nano-members (115) arranged in a period Pr may be provided. Between the transparent substrate (111) and the green color filter (113g), a plurality of nano-members (115) arranged in a period Pg may be provided (not shown). Between the transparent substrate (111) and the blue color filter (113b), a plurality of nano-members (115) arranged in a period Pb may be provided (not shown).

[0128] The display device (100A) may be formed, for example, as described below. According to one embodiment, for example, an amorphous silicon (a-Si) film may be formed on a transparent substrate (111) using a CVD (Chemical Vapor Deposition) method at a temperature of 200°C or less. In addition, a low-temperature polysilicon (p-Si) film may be formed by heating and melting the amorphous silicon using an excimer laser. After applying a resist film on the low-temperature polysilicon film, the low-temperature polysilicon film may be patterned by performing electron beam lithography and lift-off. As a result, a plurality of nano-members (115) may be formed on the transparent substrate (111).

[0129] According to one embodiment, a color filter (113) and an overcoat layer (114) can be sequentially formed on a transparent substrate (111) by covering a plurality of nano-members (115). In addition, a red conversion layer (117r), a green conversion layer (117g), and a transparent layer (118) can be formed on the overcoat layer (114). As a result, a first structure (110) can be formed. According to one embodiment, a display device (100A) can be manufactured by bonding the first structure (110) and the second structure (120) (see FIG. 1).

[0130] In the red pixel (10r) of the above display device (100A), light in the red wavelength region that has passed through the red conversion layer (117r) can be diffracted by a plurality of nano-members (115) arranged in a period Pr after passing through the overcoat layer (114) and the red color filter (113r). The diffracted light can pass through the transparent substrate (111). The green pixel (10g) and the blue pixel (10b) can also be correspondingly applied.

[0131] A display device (100A) according to the second embodiment may also have a plurality of nano-elements (115) arranged in different periods (periods Pr, Pg, Pb) in the red pixel (10r), the green pixel (10g), and the blue pixel (10b). Accordingly, as described above in the first embodiment, light in each of the red wavelength region, the green wavelength region, and the blue wavelength region can be efficiently extracted from the display device (100A) to the outside.

[0132] In addition, in the display device (100A), since a plurality of nano-members (115) are formed on a transparent substrate (111), the temperature used when forming the plurality of nano-members (115) can be allowed up to the heat resistance temperature of the transparent substrate (111). Therefore, the degree of freedom in the method of forming the plurality of nano-members (115) can be improved. In addition, since the transparent substrate (111) has high flatness, a plurality of nano-members (115) can be formed with a more precise period (period Pr, Pg, Pb).

[0133] [Variation 1]

[0134] FIG. 8 illustrates, according to one embodiment, a red pixel configuration of a display device according to Variation 1.

[0135] Referring to Fig. 8, the red pixel (10r) of the display device (100A) may have a dichroic filter (119r) between the red conversion layer (117r) and the red color filter (113r). In addition, the display device (100A) according to Variation 1 may have a configuration corresponding to the display device (100A) of the second embodiment.

[0136] The dichroic filter (119r) can transmit light in the red wavelength range while simultaneously reflecting light in the blue wavelength range. Therefore, light (light in the blue wavelength range) that has not been wavelength-converted in the red conversion layer (117r) can be reflected by the dichroic filter (119r) and re-injected into the red conversion layer (117r).

[0137] A green pixel (10g) of a display device (100A) may have a dichroic filter (not shown) between a green conversion layer (117g) and a green color filter (113g). The dichroic filter may transmit light in the green wavelength range while simultaneously reflecting light in the blue wavelength range. Accordingly, light (light in the blue wavelength range) that has not been wavelength-converted in the green conversion layer (117g) may be reflected by the dichroic filter and re-injected into the green conversion layer (117g).

[0138] The display device (100A) may have an overcoat layer (e.g., the overcoat layer (114) of FIG. 7) between the dichroic filter (119r) and the red conversion layer (117r).

[0139] A display device (100A) according to Variation 1 may also have a plurality of nano-elements (115) arranged in different periods (periods Pr, Pg, Pb) in the red pixel (10r), the green pixel (10g), and the blue pixel (10b). Accordingly, as described above in the first embodiment, light in each of the red wavelength region, the green wavelength region, and the blue wavelength region can be efficiently extracted from the display device (100A) to the outside.

[0140] In addition, since the display device (100A) has a dichroic filter (e.g., the dichroic filter (119r) of FIG. 8), it can more efficiently convert light in the blue wavelength region into light in the red wavelength region and light in the green wavelength region.

[0141] [Variation 2]

[0142] The display device (100A) according to Variation 2 may have a low refractive index overcoat layer (114) (not shown). The refractive index of the overcoat layer (114) may be, for example, 1.0 or more and 1.3 or less. In addition, the display device (100A) according to Variation 1 may have a configuration corresponding to the display device (100A) of the second embodiment.

[0143] In the above display device (100A), light (light in the blue wavelength region) that has not been wavelength-converted in the red conversion layer (117r) and the green conversion layer (117g) can be reflected between the red conversion layer (117r) and the green conversion layer (117g) and the overcoat layer (114). The reflected light can be incident again on the red conversion layer (117r) and the green conversion layer (117g).

[0144] A display device (100A) according to Variation 2 may also have multiple nano-elements (115) arranged in different periods (periods Pr, Pg, Pb) in the red pixel (10r), the green pixel (10g), and the blue pixel (10b). Accordingly, as described above in the first embodiment, light in each of the red wavelength region, the green wavelength region, and the blue wavelength region can be efficiently extracted from the display device (100A) to the outside.

[0145] According to one embodiment, since the display device (100A) has a low refractive index overcoat layer (114), it can more efficiently convert light in the blue wavelength range into light in the red wavelength range and light in the green wavelength range.

[0146] The configuration of the display device (100) described above is intended to illustrate the main components of the aforementioned embodiments and modifications, and is not limited to the aforementioned configuration and may be modified within the scope of the patent claims. Furthermore, configurations typically provided by display devices are not excluded.

[0147] For example, in the above-described embodiment, an example in which the red conversion layer (117r) and the green conversion layer (117g) include nanoparticles (1172) has been described, but the present invention is not limited thereto, and the red conversion layer (117r) and the green conversion layer (117g) may not include nanoparticles. In addition, one of the red conversion layer (117r) and the green conversion layer (117g) may not include nanoparticles.

[0148] In addition, although the above-described embodiment has been described as an example in which the light source (122) emits light in the ultraviolet to blue wavelength range, the present invention is not limited thereto, and the light source (122) may emit light in other wavelength ranges. Alternatively, a light source (122) that emits light in different wavelength ranges may be provided in the red pixel (10r), the green pixel (10g), and the blue pixel (10b).

[0149] In addition, in the above-described embodiment, the light source (122) is described as including a micro LED, but is not limited thereto, and the light source (122) may include other light-emitting elements. For example, the light source (122) includes an LED or an OLED (Organic Light Emitting Diode). The display device (100) may include a liquid crystal display element.

[0150] Additionally, in the above-described embodiment, the plurality of nano-members (115) provided in the red pixel (10r), the green pixel (10g), and the blue pixel (10b) may have the same shape or may have different shapes.

[0151] In addition, in the above-described embodiment, the blue pixel (10b) is described as having a transparent layer (118), but it is not limited thereto, and the blue pixel (10b) may have a wavelength conversion layer.

[0152] In addition, in the above-described embodiment, the case where light in the red wavelength region, light in the green wavelength region, and light in the blue wavelength region are extracted from the display device (100) is described as an example, but the wavelength region of the light extracted from the display device (100) is not limited thereto.

[0153] In addition, although the above-described Modification Example 1 and Modification Example 2 describe the display device (100A) according to the second embodiment, the display device (100) according to the first embodiment may have the same configuration. According to one embodiment, the display device (100) may have a dichroic filter (119r) or the like, and may have a low refractive index overcoat layer (114).

[0154] While the present disclosure has been illustrated and described with reference to various embodiments described above, it will be understood by those skilled in the art that various changes in form and detail may be made without departing from the scope of the present disclosure as defined by the appended claims and equivalent claims.

Claims

1. A light source provided to each of the first pixel and the second pixel and emitting light of a first wavelength; A first wavelength conversion layer formed in the first pixel and converting light of the first wavelength into light of the second wavelength; A second wavelength conversion layer formed in the second pixel and converting light of the first wavelength into light of a third wavelength different from the second wavelength; A first color filter provided to the first pixel and selectively transmitting light of the second wavelength; A second color filter provided to the second pixel and selectively transmitting light of the third wavelength; and At least a plurality of nano-materials onto which light of the second wavelength and light of the third wavelength are incident, The above plurality of nano-materials include a high refractive index dielectric, The above plurality of nano-elements are arranged in a first cycle in the first pixel, A display device wherein the plurality of nano elements are arranged in the second pixel in a second period different from the first period.

2. In paragraph 1, It further includes an overcoat layer formed between the first color filter and the first wavelength conversion layer, and between the second color filter and the second wavelength conversion layer, A display device, wherein the plurality of nano-materials are provided between the overcoat layer and each of the first wavelength conversion layer and the second wavelength conversion layer.

3. In paragraph 1, The above light source is further provided to the third pixel, A display device wherein the plurality of nano elements are further arranged in a third period different from the first period and the second period in the third pixel.

4. In paragraph 3, A display device wherein the light of the second wavelength is light in the red wavelength range, and the light of the third wavelength is light in the green wavelength range.

5. In paragraph 4, The above first cycle is longer than the above second cycle, The second cycle is a longer display device than the third cycle.

6. In paragraph 4, A display device wherein the first period is 500 nm to 700 nm, the second period is 450 nm to 500 nm, and the third period is 350 nm to 430 nm.

7. In paragraph 1, The plurality of nano-materials arranged in the first cycle resonate with light of the second wavelength, A display device in which the plurality of nano-elements arranged in the second cycle resonate with light of the third wavelength.

8. In paragraph 1, A display device, wherein the first wavelength conversion layer and the second wavelength conversion layer each include a plurality of nanoparticles.

9. In paragraph 1, A display device in which the light of the first wavelength is light in the blue wavelength range.

10. In paragraph 1, A display device wherein the first wavelength conversion layer and the second wavelength conversion layer each include at least one of a quantum dot and a fluorescent substance.

11. In paragraph 1, An overcoat layer formed between the first color filter and the first wavelength conversion layer, and between the second color filter and the second wavelength conversion layer; It further has a transparent substrate facing the overcoat layer, with the first color filter and the second color filter interposed therebetween, A display device wherein the plurality of nano-materials are provided between the transparent substrate, the first color filter, and the second color filter.

12. In paragraph 1, A first dichroic filter provided between the first wavelength conversion layer and the first color filter, wherein the first dichroic filter transmits light of the second wavelength and reflects light of the first wavelength; A display device further comprising a second dichroic filter provided between the second wavelength conversion layer and the second color filter, the second dichroic filter transmitting light of the third wavelength and reflecting light of the first wavelength.

13. In paragraph 1, A display device, wherein a plurality of nano-elements provided in a red pixel, a green pixel, and a blue pixel are configured to have the same shape or different shapes.

14. In paragraph 13, The blue pixel has a transparent layer, A display device having a blue pixel and a wavelength conversion layer.

15. In paragraph 1, The above display device is a display device having an overcoat layer having different color filters and a low refractive index.

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