JP7683340B2 - Black matrix substrate and display device including black matrix substrate - Google Patents

Description

The present invention relates to a black matrix substrate used in liquid crystal display devices, micro LEDs (LED displays), organic EL display devices, etc., and also to a display device equipped with a black matrix substrate.

Information display devices such as liquid crystal display devices, micro LED (Light Emitting Diode) displays, and organic electroluminescence (EL) display devices can be considered to be composed of a black matrix substrate and a display function layer, as shown in FIG. 1(a). The display function layer has the function of displaying image information as a distribution of colors and light intensity by controlling the amount of transmitted light for each pixel using an electric signal, as in liquid crystal, or by emitting light at an intensity corresponding to the electric signal, as in organic electroluminescence (EL) and micro LED. The black matrix substrate has the function of suppressing the leakage of light from adjacent pixels through the gaps between pixels, the transmission of light through uncontrolled areas of the gaps, and the decrease in contrast due to the reflection of external light. The present invention relates to the layer structure of a black matrix substrate shown in FIG. 1(b) described later, and a display device using the same.

As described below, FIG. 5 shows a cross section of a display device in which the display function layer is a micro LED. FIG. 6 shows a cross section of a liquid crystal display device in which the display function layer uses a combination of a backlight with a mini LED light source and a liquid crystal that modulates the amount of light.

In recent years, attention has been focused on a technology for LCD displays that uses direct-lighting backlights called mini-LEDs, which are made up of multiple LED chips with sizes of approximately 5 μm to 100 μm arranged in a matrix. Mini-LEDs typically use three types of LED chips (hereinafter sometimes referred to as light-emitting elements) that emit red, green, and blue light.

Also attracting attention is a technology that uses local dimming in which the light emission brightness of three types of LED chips is partially adjusted or light emission is partially stopped depending on the position of the display portion on the display screen.
In such a liquid crystal display device using local dimming, the light emission on the display screen can be partially turned off, so the contrast of the display can be greatly improved. In a conventional liquid crystal display device, the backlight is always on, so a small amount of light leaks when the liquid crystal displays black, making it difficult to obtain a contrast comparable to that of an organic EL display.

Micro LEDs are displays that have a structure in which LED chips with sizes of approximately 2 μm to 100 μm are arranged in a matrix, and display images by individually driving each of the multiple LED chips. Such micro LEDs can display images without using liquid crystal.

Micro LEDs are roughly divided into a system using three types of LED chips, red, green, and blue, as in the case of the mini LEDs described above, and a system using only a monochromatic LED chip, such as a light-emitting LED chip that emits light in the blue to near-ultraviolet wavelength range. In micro LEDs, each LED chip plays the role of a display function layer.
In a method using monochromatic LED chips, color display is achieved by stacking a wavelength conversion layer (e.g., a dispersion of quantum dots or phosphors) on each of multiple monochromatic LED chips, which converts the emission wavelength to either red, green, or blue.
Organic EL is an abbreviation of organic electroluminescence. Organic EL display devices are display devices that use light emitted by recombination of electrons and holes injected into an organic compound as a display function layer for display. Organic EL display devices are broadly classified into a type that uses three types of light-emitting layers that emit red, green, and blue light, and a type that combines a white light-emitting layer that emits white light with a color filter.
In the liquid crystal display device, the micro LED, and the organic EL display device, the light emitted from the display function layer does not have sufficient linearity toward the pixel aperture, which results in stray light (obliquely emitted light) toward adjacent pixels, resulting in a decrease in display contrast.

In particular, as pixel size becomes smaller, degradation of display contrast caused by stray light becomes a problem. In addition, when a display device is used in a bright environment, degradation of display contrast caused by external incident light entering the display device becomes a problem.
In organic EL display devices and micro LEDs, a circular polarizer is used to prevent contrast degradation caused by incident light entering the display device from the outside. In organic EL display devices and micro LEDs, the circular polarizer is mounted on the upper surface of the display device in order to eliminate reflection of external light at light-reflective pixel electrodes and improve visibility. However, since the circular polarizer is expensive, there is a strong demand for the omission of the circular polarizer in terms of the structure of the display device.

Patent Document 1 discloses a black matrix with a two-layer structure (see FIG. 1 of Patent Document 1). However, the technology of Patent Document 1 is a technology for displaying a stereoscopic image to a naked-eye observer. Patent Document 1 does not address the issue of contrast reduction in display devices that use various display function layers. Patent Document 1 does not propose a configuration that omits an expensive circular polarizer, and in addition, it does not disclose a technology for suppressing surface reflection of the black matrix.

Patent Document 2 describes a color filter using a first light-shielding layer and a second light-shielding layer. However, Patent Document 2 does not propose a configuration that omits an expensive circular polarizer, and does not disclose a technology for suppressing surface reflection of the first light-shielding layer. Patent Document 2 does not consider a configuration that does not include a color filter. In a micro LED having red light-emitting elements, green light-emitting elements, and blue light-emitting elements, or in a mini LED using red light-emitting elements, green light-emitting elements, and blue light-emitting elements and a liquid crystal layer, the color filter can be omitted. Similarly, an organic EL display device with improved color purity does not require a color filter. In a liquid crystal display device, the color filter can also be omitted in a field sequential display in which the red, green, and blue emissions of an LED backlight are sequentially turned on to display the image.

However, in Patent Document 2, the feature that the second light-shielding layer covers the end of the colored layer, and the feature regarding the width of the second light-shielding layer in claim 3 are almost the same as the color filter shown in Fig. 16 of Patent Document 1. Patent Document 1 also describes a problem regarding the alignment of the first light-shielding layer and the second light-shielding layer. The technology from [0034] to [0036] related to the second light-shielding layer in Patent Document 2 is also described in, for example, paragraph [0105] of Patent Document 1.
Neither Patent Document 1 nor Patent Document 2 discloses or suggests a technology for improving visibility by using a light scattering layer, nor a technology for reflecting light emitted from a light source such as a backlight or an LED light-emitting element at the black matrix and returning it to the light source for reuse.

Patent No. 5804196 Patent No. 6225524

10 shows a conventional example of a display device equipped with a direct type backlight unit 55 having blue LEDs as light emitting elements 51. In this conventional example, a liquid crystal panel 50 is shown as a display functional part above the direct type backlight unit 55. A color filter including a black matrix is disposed on the liquid crystal panel 50. To indicate pixel positions, pixels a, b, c, d, and e are shown in a schematic diagram within the liquid crystal panel.

The direct type backlight unit 55 comprises a number of light emitting elements, a diffusion plate 52 above the arrangement of the light emitting elements, a wavelength conversion sheet 53, and, for example, two orthogonal prism sheets 54. The light emitting elements are often a number of LED chips individually packaged in a metal case. The wavelength conversion sheet is used to convert part of the blue light emitted by the light emitting elements into red and green, thereby obtaining the three colors red, green, and blue.

The light-emitting portion of these LED chips is generally filled with phosphors and light-scattering particles together with silicone resin. Since LED light is highly linear and emitted from the center of the LED chip, one of the roles of these phosphors and light-scattering particles is to scatter the light in order to expand the field of view. However, in a configuration in which LED chips packaged in this way are arranged in a backlight unit, the light emitted from the LED chip is scattered, and is diffused before it reaches the color filter provided in the pixel aperture, reducing the contrast, which is undesirable. In other words, it becomes difficult to obtain a sufficient effect when applying local dimming.

Both the diffusion plate 52 and the wavelength conversion sheet diffuse light. For example, the light emitted from a c-LED (blue LED) located directly below a c pixel will travel not only to the c pixel but also to the surrounding adjacent pixels a, b, d, e, etc., further reducing the effect of local dimming.
This problem of reduced contrast due to light scattering or stray light into adjacent pixels has not been solved not only in liquid crystal display devices but also in LED displays known as micro LEDs.

The present invention has been made in consideration of the above-mentioned background technology and problems, and provides a black matrix substrate and a display device equipped with a black matrix substrate that can improve the display contrast and brightness in display devices such as liquid crystal display devices, micro LEDs (LED displays), and organic EL display devices, which require even higher definition.

A black matrix substrate according to a first aspect of the present invention at least comprises: a transmittance adjusting layer which is a dispersion of carbon black, transparent fine particles, and a resin, on one surface of a transparent substrate; a first black matrix having a plurality of openings which are defined in a plan view by a line width Ax in a first direction and a line width Ay in a second direction; a light scattering layer which covers the plurality of openings and the first black matrix; a second black matrix which is defined on the light scattering layer so as to overlap at the centers of the line width Ax and the line width Ay of the first black matrix, respectively, and has a plurality of openings which are defined by a line width Bx in the first direction and a line width By in the second direction; and a light reflective matrix which is defined on the second black matrix so as to overlap at the centers of the line width Bx and the line width By, respectively , and has a plurality of openings which are defined by a line width Cx in the first direction and a line width Cy in the second direction, wherein the line width Ax, the line width Cx, the line width Ay, and the line width Cy satisfy the relationship of the following formulas (1) and (2).
Ax>Bx≧Cx...(1)
Ay>By≧Cy... (2)
The light scattering layer included in the configuration of the black matrix substrate of the present invention can be a light scattering layer containing optically isotropic transparent particles.

The light scattering layer included in the configuration of the black matrix substrate of the present invention may be a light scattering layer containing zinc oxide particles.
The light scattering layer included in the configuration of the black matrix substrate of the present invention may be a light scattering layer containing carbon black and a blue pigment.
The light scattering layer included in the configuration of the black matrix substrate of the present invention may be a light scattering layer containing an ultraviolet absorbing agent.
The light-reflective matrix included in the configuration of the black matrix substrate of the present invention can be configured in a two-layer configuration in which a thin film of titanium or titanium nitride and a thin film of an aluminum alloy containing neodymium are laminated on the second black matrix.
The light-reflective matrix included in the configuration of the black matrix substrate of the present invention can be a black matrix substrate having a three-layer configuration including a thin film of a first conductive oxide, a thin film of silver or a silver alloy, and a thin film of a second conductive oxide laminated on the second black matrix.

The black matrix substrate according to the first aspect of the present invention may have a configuration in which a first transparent resin layer is inserted between the light scattering layer and the second black matrix.
In the black matrix substrate according to the first embodiment of the present invention, a second transparent resin layer can be laminated on the light reflective matrix.
A display device according to a second aspect of the present invention can be a display device including the black matrix substrate according to the first aspect and at least a display function layer.
In the display device according to the second aspect of the present invention, the display function layer may be a red light emitting element, a green light emitting element, and a blue light emitting element, each of which is driven by a thin film transistor.
In the display device according to the second aspect of the present invention, the display function layer may be a red light emitting diode, a blue light emitting diode, and a green light emitting diode, each of which is driven by a thin film transistor.

The display device according to the second aspect of the present invention can have the display function layers as liquid crystal layers each driven by a thin film transistor, and can have a backlight unit including a plurality of optical modules each having a red light emitting diode, a blue light emitting diode, and a green light emitting diode.

The light-emitting element (or light-emitting diode) that is preferably used in the present invention is preferably a light-emitting element with directionality. For example, in a light-emitting element in which red, green, and blue LED chips are mounted in separate housings, it is preferable for the light-emitting element to have no light-scattering particles or wavelength-converting phosphors stacked on the LED chips in the housing.

The present invention provides a black matrix substrate that has a simple configuration but provides high display quality when used as a display device, and a display device equipped with the same.

1A is a cross-sectional view of a display device according to a first embodiment of the present invention, FIG. 1B is a cross-sectional view of a black matrix substrate, FIG. 1C is a cross-sectional view of part A, and FIG. 10A is a cross-sectional view of a black matrix substrate, and FIG. 10B is a cross-sectional view of part A according to a second embodiment of the present invention. 2 is a plan view from direction C (as viewed from light-reflective matrix 5) of the cross-sectional view of FIG. 1. FIG. 4 is a cross-sectional view of a black matrix substrate showing the path along which light L6 emitted from a light source travels. FIG. FIG. 11 is a cross-sectional view of an LED display according to a second embodiment of the present invention. FIG. 11 is a cross-sectional view of a liquid crystal display device according to a second embodiment of the present invention. FIG. 7 is a cross-sectional view of the optical module 510. 4 is an equivalent circuit diagram of a pixel electrode driving circuit. FIG. FIG. 2 is an equivalent circuit diagram of an LED driver circuit. FIG. 1 is a schematic cross-sectional view of a conventional display device equipped with a direct type backlight unit. 13 is a reflectance spectrum of a display device according to an embodiment of the present invention, in which a transmittance adjustment layer is provided between a transparent substrate and a black matrix. 1 is a reflectance spectrum of a display device using a conventional black matrix.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
In the following description, the same or substantially the same functions and components are denoted by the same reference numerals, and their description is omitted or simplified, or is described only when necessary. In each drawing, the dimensions and ratios of each component are appropriately changed from the actual ones in order to make each component large enough to be recognized on the drawing. In addition, as necessary, elements that are difficult to illustrate, such as the configuration of thin film transistors, the structure of multiple layers that constitute a conductive layer, wiring connections to circuit parts, switching elements (transistors), etc., are omitted or partially illustrated.

In each of the embodiments described below, we will explain the characteristic parts, and will omit explanations of parts that are the same as those in the display device according to this embodiment and the components used in a normal display device.

Ordinal numbers such as "first" and "second" in the first black matrix, second black matrix, first substrate, second substrate, and third substrate are used to avoid confusion of components and do not limit the quantity. The matrix arrangement of light-emitting elements refers to an arrangement in which light-emitting units containing one or more light-emitting elements are arranged in a matrix at a certain pitch in a plan view. In the following description, a substrate on which light-emitting elements are arranged in a matrix, or a substrate on which light-emitting units are arranged in a matrix at a certain pitch, may be called an optical module. It is preferable to also arrange thin-film transistors that drive the light-emitting elements and light-emitting units on the substrate. When the display function layer is a liquid crystal layer, this optical module is called a direct-type backlight. The light-emitting units may be surrounded by partitions in a grid pattern in a plan view when used as a display device. The light-emitting units surrounded by grid-shaped partitions in a plan view each include one or more light-emitting elements that are light-emitting diodes. In the following drawings (cross-sectional views), even when one light-emitting element is illustrated in a partition, it is assumed that multiple light-emitting elements are arranged in the partition. In a display device using the local dimming technology described below, the on/off driving and brightness of light emission can be adjusted for each light-emitting unit, which includes, for example, one or more light-emitting elements, or for multiple light-emitting units. Note that with local dimming technology, the number of pixels can be greater than the number of light-emitting elements included in a light-emitting unit in a planar view. In other words, the advantage of local dimming is that the display device can be driven more efficiently because the number of light-emitting elements is smaller than the number of pixels. Note that in a planar view, a matrix-shaped (lattice-shaped) partition wall can reduce the adverse effects of stray light on adjacent pixels more than, for example, a stripe-shaped partition wall.

In the description of the present invention, the configuration in which the black matrix substrate and the optical module are bonded to face each other includes, for example, a configuration in which an array substrate on which a liquid crystal layer and thin-film transistors that drive the liquid crystal are arranged is inserted between the black matrix substrate and the optical module. In this configuration including a liquid crystal layer, the optical module functions as a direct-type backlight unit.

The term "planar view" in the specification can refer to a "planar view" seen from one surface of the transparent substrate, or a "planar view" seen in the normal direction from a second surface of the transparent substrate (the surface opposite to the first surface). Alternatively, for the purposes of explaining the light-reflecting matrix and the partition structure described below, it can refer to a "planar view" seen from the film surface of the light-reflecting matrix.

In an embodiment of the present invention, the "display function layer" of the display device can be made up of a plurality of light-emitting diode elements called LEDs (Light Emitting Diodes), a plurality of organic EL (organic electroluminescence) elements also called OLEDs (Organic Light Emitting Diodes), or a liquid crystal layer. In the following description, LEDs, LED chips, and light-emitting diode elements may be simply referred to as light-emitting elements.

In addition, the openings of the first black matrix or the second black matrix, or some of the light-emitting elements (light-emitting diodes) in the present invention overlap with the center lines of their respective central positions.

LED is a light emitting diode (Light Emitting Diode), and compounds such as aluminum gallium arsenide (AlGaAs), gallium arsenide phosphide (GaAsP), indium gallium nitride (InGaN) / gallium nitride (GaN) / aluminum gallium nitride (AlGaN), gallium phosphide (GaP), zinc selenide (ZnSe), and aluminum indium gallium phosphide (AlGaInP) are applied to LED. As a monochromatic light emitting LED, blue light emitting diodes, which will be described later, are mainly applied with gallium nitride (GaN). The light emitting diode element applied to the present invention is preferably a blue light emitting diode whose emission peak wavelength is 430 nm or more and 460 nm or less. The blue light emitting diode may also include light emission in the near ultraviolet region, such as 365 nm, 385 nm, and 395 nm.

In the mini-LED, for example, an LED chip of 40 μm to 200 μm in size can be used. In the micro-LED, for example, an LED chip of 2 μm to 60 μm in size can be used. The structure of the LED chip may be a horizontal LED in which the n-side electrode and the p-side electrode are on the same side, but it may also be a vertical LED in which the n-side electrode and the p-side electrode are on different surfaces (opposite parallel surfaces) in the thickness direction of the LED. In the following description, the upper electrode and the lower electrode refer to either the n-side electrode or the p-side electrode of the vertical LED.
First Embodiment
[Transparent substrate]
The material of the transparent substrate (first transparent substrate) 100 applicable to the black matrix substrate 110 of the present invention may be a transparent substrate such as a glass substrate, a quartz substrate, a sapphire substrate, or a plastic substrate including a polyimide film.
In addition, when constructing a display device by bonding together an array substrate having a display function layer and a plurality of thin film transistors that drive the display function layer arranged in a matrix form and a black matrix substrate 110, it is preferable that the substrate materials of the array substrate and the black matrix substrate are the same.

The second substrate 200, 300 on which a plurality of light-emitting elements are arranged in a matrix as shown in FIG. 5 and FIG. 6 may be made of the same material as the transparent substrate 100, but may be a substrate colored black or other colors. The second substrate 200, 300 may be a sapphire substrate, or a silicon substrate on which CMOS elements (transistors, etc.) are arranged. It may be a silicon substrate on which crystal-grown LED elements (light-emitting elements) are arranged via a buffer layer. The light-emitting elements 24 (blue LED 21, green LED 22, red LED 23) may be mounted by flip-chip mounting using a low-melting-point alloy, mounting using an anisotropic conductive film, or wire bonding using gold wires. The second substrate may be provided with a plurality of thin-film transistors for driving the LED elements or the liquid crystal layer.
[Transmittance adjustment layer]
The transmittance adjusting layer is a layer formed on one surface of the transparent substrate, which has the role of adjusting the transmittance to improve visibility and also reducing the reflectance, as described later.
The transmittance adjusting layer 2 is a dispersion of at least carbon black, transparent fine particles, and a resin. The transmittance adjusting layer 2 is a resin dispersion containing carbon black as a main pigment, and it is preferable that the transmittance of the transmittance adjusting layer 2 for visible light is in the range of 70% or more and 99.7% or less. From the viewpoint of this transmittance, the amount of carbon black added to the resin dispersion is adjusted.

Micro LEDs and organic EL display devices often have a light-reflective electrode underneath the LED or organic EL layer, which is the light-emitting element. In micro LEDs and organic EL display devices with this structure, external incident light is reflected back by the light-reflective electrode and enters the observer's eyes, reducing visibility. In micro LEDs and organic EL display devices, an expensive circular polarizer is usually used in combination with the display device to eliminate the re-reflection of external incident light. The visible light transmittance of a circular polarizer is approximately 50%.

The transmittance adjustment layer 2 in the present invention has two roles. The first role is to suppress re-reflected light of externally incident light by the light-reflective electrode. By setting the transmittance of the transmittance adjustment layer 2 in the range of 70% to 99.7%, re-reflected light of externally incident light is suppressed. Such transmittance adjustment of the transmittance adjustment layer can be easily achieved by adding carbon black, a black pigment, in the range of, for example, 0.2 wt% to 8 wt% relative to the resin solid content. Adding carbon black in an amount exceeding 9 wt% or even 10 wt% reduces the transmittance of the transmittance adjustment layer too much.

In addition, by disposing a scattering film 2 having a light scattering function on the black matrix substrate 110, the specular reflection component of the re-reflected light of the external incident light can be eliminated (specular reflection light will not enter the observer's eyes). The second role of the transmittance adjustment layer 2 in the present invention is to reduce the reflectance of the first black matrix. The reduction in reflectance of the first black matrix will be explained below with reference to Figures 11 and 12. This will be described in more detail in the following examples. The reduction in reflectance of the first black matrix can be easily achieved by inserting a transmittance adjustment layer at the interface between the transparent substrate such as glass and the first black matrix using a coating solution with a dilute side of the carbon black addition (for example, 0.2 wt% to 2 wt%).

Figure 11 shows the reflectance when the transmittance adjustment layer according to the present invention is disposed at the interface between a transparent substrate such as glass and a black matrix (first black matrix). Figure 12 shows the reflectance at the interface between a transparent substrate and a black matrix in a conventional configuration. As shown by reflectance BL1 in Figure 11 and reflectance BL2 in Figure 12, a low reflectance can be obtained by disposing the transmittance adjustment layer. By further adding a small amount of blue pigment to the transmittance adjustment layer, the transmittance for light wavelengths of 600 nm and above (on the red side) can be further reduced.

When external light is assumed to be incident on the display surface, the external light passes through the transmittance adjustment layer 2 once, is reflected by the light-reflective electrode, and then passes through the transmittance adjustment layer 2 again to be emitted to the viewer side. This double passage of light can rapidly reduce the reflection of external light. If the visible light transmittance of the transmittance adjustment layer 2 is 70% or more, and if the intensity of the light emitted from a light-emitting element such as an LED is equivalent to that of a display device using a circular polarizer, the display device according to the present invention can provide a brighter display.

Moreover, many LCD displays use two polarizing plates in a crossed Nicol configuration (with orthogonal polarization axes). When using such a circular polarizing plate or polarizing plate, fine particles that do not cause polarization distortion, are optically isotropic, and are transparent in the visible range can be added to the transmittance adjustment layer in order to improve dispersion or reduce the refractive index of the semi-transparent film.

For example, if 2 is a transparent inorganic film or a resin film with nearly 100% transmittance of visible light, ripples due to interference may occur in the light reflection at the interface with the first black matrix 1, and the first black matrix 1 may be observed to be slightly colored. Such slight coloring caused by reflected light is easily observed when the display device is turned off and black is displayed. In such cases, it may appear rainbow-colored when viewed from an oblique direction by an observer, which may reduce visibility.

In contrast, by using silica fine particles and carbon black in combination to form the transmittance adjusting layer 2, the effect of reducing the size of such ripples can be obtained. From the above viewpoint, the transmittance adjusting layer 2 containing fine particles that are transparent in the visible range is useful. The same effect can be obtained by not containing silica fine particles and by containing a low concentration of carbon black.
The particle size of the transparent particles such as silica fine particles is not specified, but for example, transparent particles having an average primary particle size of 3 nm to 100 nm can be applied. The film thickness of the transmittance adjusting layer is preferably in the range of, for example, 0.1 μm to 1 μm, but may be 1 μm or more.

In addition, when the transmittance adjustment layer is formed with an organic pigment as the main pigment component, the reflected light of external light at the interface with the first black matrix may appear yellow. In contrast, the transmittance adjustment layer 2 containing carbon black as the main pigment component has almost flat reflected light and is hardly colored. Flat reflected light means that in the visible range of light wavelengths from 400 nm to 700 nm, for example, in a small range such as 50 nm, there is no unevenness (fluctuation) of 2% or more in transmittance, and a transmittance curve close to a straight line is obtained. In other words, when the visible range of 400 nm to 700 nm is divided into 50 nm units, the magnitude of the reflectance fluctuation (ripple) within the 50 nm unit can be 1.0% or less. In addition, in the visible range of light wavelengths from 400 nm to 700 nm, the reflectance at the interface with the first black matrix can be in the range of 0.01% to 1.0%. The reflectance fluctuation (ripple) is the difference between the peaks and valleys of the reflectance spectral curve within the 50 nm unit described above for the reflectance measured in the visible range of light wavelengths from 400 nm to 700 nm, but as a simple evaluation, the reflectance peak value within the 50 nm unit may also be used. In the latter simple evaluation, the apparent reflectance fluctuation value will be a large value.

The reflectance here is the reflectance measured through the transparent substrate and the transmittance adjustment layer, with the reflectance of the aluminum film as the standard (100%). Measurements can be easily performed using, for example, a microspectrophotometer. Note that the optically isotropic transparent fine particles play an important role in suppressing reflectance fluctuations. To further suppress reflectance fluctuations and achieve low reflectance, the transmittance adjustment layer may contain trace amounts of carbon black or blue pigment in the resin along with the transparent particles.

The resin may be any resin that can provide the necessary reliability, such as heat resistance, for the transmittance adjusting layer 2. An alkali-developable photosensitive resin or a thermosetting resin may be used. The thermosetting resin may be, for example, an epoxy group-containing compound or resin, or a resin having at least one group selected from a methylol group, an alkoxymethyl group, or an acyloxymethyl group. These resins are used as a coating liquid dispersed together with transparent particles and an organic solvent, coated on a transparent substrate, and finally cured to form the transmittance adjusting layer 2.
[Black matrix]
The first and second black matrices (hereinafter sometimes simply referred to as black matrices) according to the present invention can be made by dispersing a black pigment having a visible light absorbing function, such as carbon black, in a resin.

In the black matrix substrate according to the present invention, a metal thin film such as aluminum is used as a light reflective matrix, which will be described later. A metal thin film such as aluminum has high light blocking properties. By setting the thickness of the light reflective matrix to, for example, 0.15 μm or more and 0.8 μm or less, light transmission in the film thickness direction can be eliminated.
Therefore, the black matrix according to the present invention does not need to have a high light-shielding property. For example, an optical density OD in the range of 2 to 3 is sufficient. An optical density of 4 or more may be used, but this increases the process load such as exposure time. If the optical density is 1 or less, the reflection of external light from a thin metal film such as aluminum is easily visible, which may lead to a deterioration in the image quality of the display device. The concentration of black pigment such as carbon black and its film thickness can be set to a carbon black concentration that can be set in the above optical density range.

The above features of the black matrix are common to the first black matrix and the second black matrix. The first black matrix and the second black matrix are each a lattice pattern in a plan view, and overlap with the same line width center in the first direction (X direction) and the second direction (Y direction). In other words, the center positions of the openings in the plan view are also overlapped. By making the first black matrix and the pattern of the light reflective matrix described later into a lattice pattern that divides the openings, the influence of stray light on adjacent pixels in the first direction (X direction) and the second direction (Y direction) can be reduced, thereby improving the display quality. When both matrix patterns are stripe patterns, the adverse effect of stray light is likely to occur on adjacent pixels in the extension direction of the stripe patterns.
If necessary, color filters of blue, green, red, etc. may be disposed in the openings of the black matrix.
[Scattering film]
In the present invention, as shown in FIG. 1, FIG. 4, etc., a light scattering layer 10 can be provided.
The light scattering layer 10 is basically a dispersion of transparent resin and transparent particles 8. As described above, for example, transparent particles having an average particle size of 1 μm or more and 3.0 μm or less can be used as the transparent particles 8. Optically isotropic transparent particles can be used as the transparent particles 8. "Optical isotropic" means that the transparent particles applied to the embodiment of the present invention have a crystal structure in which the a-axis, b-axis, and c-axis are equal to each other, or are amorphous, and the propagation of light is isotropic without being affected by the crystal axis or crystal structure. Silica particles have a non-crystalline structure (amorphous). As resin particles such as resin beads, particles having various properties including refractive index are known, and these particles can be used in combination. Resin particles such as acrylic resin, polystyrene, polyurethane, nylon, melamine resin, and benzoguanamine resin may be used in combination. For example, light scattering particles having an average particle size of 1.0 μm or more and 3.0 μm or less in microns are preferably used for the light scattering layer 10. In other words, by using particles having a particle diameter larger than the wavelength of visible light, it is easy to obtain suitable light scattering properties for the scattering film 10. Also, transparent fine particles having an average particle diameter of about 0.2 μm or 0.1 μm or less may be used in combination from the viewpoint of a dispersion assistant. The above transparent particles 8 or transparent fine particles can be dispersed in a transparent resin or a resin containing an ultraviolet absorber to form the light scattering layer 10. Transparent particles or transparent fine particles of zinc oxide that are transparent in the visible range and can absorb ultraviolet rays of 390 nm or less can also be used. In the description of the present invention, particles having an average primary particle diameter of 1 μm or more are referred to as transparent particles, and particles having an average primary particle diameter of 0.2 μm or less are referred to as transparent fine particles.

Examples of ultraviolet absorbers include benzophenone compounds, benzotriazole compounds, and triazine compounds. The ultraviolet absorber preferably has a phenolic hydroxyl group. By providing a phenolic hydroxyl group, crosslinking with a compound having an alkoxymethyl group or a methylol group can be performed during heat treatment. Crosslinking can suppress bleeding out of the ultraviolet absorber during long-term storage after hardening, improving reliability. The amount of ultraviolet absorber added can be, for example, 0.05% by mass or more and 10% by mass or less based on the solid content of the transparent resin.

The thickness of the light scattering layer 10 is a dispersion of transparent particles 8 that are larger than the wavelength of light, and in this respect can be set to 1 μm or more and 50 μm or less. It can be formed to be thicker than 50 μm, but there is little improvement in scattering properties by making it thicker than 50 μm. On the contrary, forming it thick tends to increase the process load, for example, wasteful work time for coating and drying.

Light scattering does not have to be limited to the dispersion of transparent particles in a transparent resin. For example, it is possible to apply and dry a dispersion liquid in which two types of resin with different refractive indexes are dissolved in an organic solvent, thereby causing phase separation between the two types of resin and imparting light scattering properties.

In a display device that does not use a circular polarizer or a polarizer, the transparent particles 8 do not need to be optically isotropic, and the range of choices for the transparent particles 8 can be expanded. For example, zinc oxide particles can be used as the transparent particles 8 that can be added to the scattering film 10. Zinc oxide has high transmittance in the visible range of 400 nm to 700 nm and can absorb ultraviolet rays of 390 nm or less. From this perspective, it makes sense to use zinc oxide transparent particles and transparent fine particles in a display device that does not use a circular polarizer.

An ultraviolet absorbing agent can be further added to the transmittance adjusting layer 2 and the light scattering layer 10 described later. Many of the phosphors and quantum dots used in the wavelength conversion layer are easily excited by secondary light with light in the short wavelength region. This can cause unintended emission of light on the screen of an LED display such as a micro LED when strong external light such as sunlight is incident, which can reduce visibility. In order to suppress unintended emission of light from the wavelength conversion layer due to external light, an ultraviolet absorbing agent can be added to the transmittance adjusting layer 2 and the light scattering layer 10. In addition, the ultraviolet absorbing agent added to the light scattering layer 10 can absorb ultraviolet light when it is contained in the emission of a light emitting element such as a blue LED, and prevent it from entering the viewer's eyes.

Furthermore, when light scattering particles (transparent particles) having an average particle size of 1.0 μm to 3.0 μm in micron units are used for light scattering, the surface unevenness of the light scattering layer 10 becomes large and needs to be flattened. That is, the light scattering layer 10 according to the present invention can have a laminated structure with the transmittance adjusting layer 2 as a flattening film made of a resin layer containing an ultraviolet absorbing agent.
[Light-reflecting matrix]
The light-reflective matrix 5 has a structure in which a light-reflective metal thin film is superimposed on one surface of the black matrix, and is laminated in the same lattice pattern as the black matrix.
As described above, a metal thin film made of aluminum or an aluminum alloy has a high light-shielding effect when the thickness of the metal thin film is more than 0.1 μm. In addition, a metal thin film made of aluminum or an aluminum alloy has a high light reflectance. The light-reflective matrix 5 according to the present invention utilizes this light reflection to return light emitted from a light source such as a light-emitting diode to the light source side for reuse.

As the resolution of liquid crystal display devices and LED displays increases, the area ratio of the black matrix to the aperture area increases. With the increase in resolution to 600 ppi, 800 ppi, and even 1000 ppi or more, the black matrix area ratio exceeds 60% and in some cases exceeds 70% (the aperture area ratio decreases).
The present invention proposes a configuration in which a light reflective matrix is provided on the rear surface (the surface opposite to the first black matrix) of the second black matrix facing the first black matrix.
Fig. 4 is a cross-sectional view showing how light L6 emitted from a direct type backlight unit or a light source such as a light emitting diode is reflected by a light reflective matrix 5 and returns to the light source side as light L7. Fig. 7 is a cross-sectional view of a direct type backlight unit 510 in which light emitting diodes 21, 22, and 23 are arranged.

The light reflected in this manner (for example, L7) is guided to the reflective electrode 18, the partition wall 28,
Or it hits various components such as light-emitting diodes and is reflected again. Utilizing the reflected light can contribute to improving the brightness of the display device. As mentioned above, blue light is easily absorbed by reflection and scattering, and repeated reflection tends to make the display yellowish. From this point of view, it is also useful to add a blue pigment to the resin layer on the black matrix substrate side, such as the light scattering layer 10, the transmittance adjustment layer, and the first transparent resin layer, in order to reduce the yellowish color. In addition, a light-reflective metal thin film, an increased reflection film, or a reflective sheet may be separately installed in the direct backlight unit.

Figure 4 shows a situation in which light L1 incident on the scattering film 10 from an oblique direction is repeatedly reflected and adversely affects the adjacent pixel P2 as light L5 (stray light). As shown, the horizontal diffusion of light is improved by dispersing carbon black or a blue pigment in the light scattering layer 10, which is the scattering functional part, or in the transmittance adjustment layer 2, which also serves as the ultraviolet absorbing functional part. The light absorption by the two layers, the first black matrix 1 and the second black matrix 4, also improves the adverse effects of stray light.

1 and 4 are cross-sectional views of a black matrix substrate including illustrations of a first black matrix 1, a second black matrix 4, and a light-reflective matrix 5. Fig. 3 is a plan view of Fig. 1 as viewed from direction B (the direction from the light-reflective matrix 5). The scattering film 10 is not shown.
It is preferable to form the line width of the first black matrix 1 and the second black matrix 4, or the first black matrix, wider than the line width of the light-reflective matrix 5. If the second black matrix 4 is not provided, the light-reflective matrix 5 may be viewed obliquely in the direction of the observer 20 (direction indicated by Z). If the light-reflective matrix 5 is viewed by the observer 20, the display quality of the display device is reduced. In order to improve visibility from an oblique direction, the second black matrix 4 is provided, but if the line width Ax of the first black matrix 1 is sufficiently wider than the line width Cx of the light-reflective matrix 5, the formation of the second black matrix 4 may be omitted. If the line width Ax of the first black matrix 1 is wider than the line width Cx of the light-reflective matrix 5, the line width Bx of the second black matrix 4 may be made equal to the line width Cx of the light-reflective matrix.
The above-mentioned line width relationships can be summarized as follows:
Ax>Bx≧Cx・・・(1)
Ay>By≧Cy・・・(2)
The aluminum alloy may be one to which a small amount of high melting point metal such as Mo or Ti, Si, or rare earth such as Nd (neodymium) is added. From the viewpoint of reflectivity, an aluminum alloy containing 0.2% by mass or more and 3% by mass or less of Nd (the remainder being unavoidable impurities) is preferable. If Nd is less than 0.2% by mass, the reflectivity is likely to decrease due to coarsening of aluminum crystals or formation of hillocks. Furthermore, if Nd exceeds 3% by mass, the reflectivity tends to decrease. If Nd is in the range of 0.2% by mass or more and 3% by mass or less, a high reflectivity is likely to be reproduced stably.

Silver or a silver alloy may be used as the thin metal film of the light reflective matrix 5. Since silver and silver alloys have low adhesion, a configuration in which they are sandwiched between conductive oxides including indium oxide, zinc oxide, or the like can be applied.
In addition, a light scattering element, such as a second light scattering layer, may be laminated on the light reflecting matrix.

Example 1
Example 1, which is a black matrix substrate, will be described with reference to FIGS.
FIG. 1A is a cross-sectional view of a black matrix substrate 110 according to the first embodiment.
The black matrix substrate 110 is configured by laminating, in this order, a transmittance adjusting layer 2, a first black matrix layer 1, a light scattering layer 10, a second black matrix layer 4, and a light reflective matrix 5 on the second black matrix layer 4 on the transparent substrate 100. The light scattering layer 10 is
It has a light scattering function of dispersing transparent particles 8. The light scattering layer 10 can have a two-layer structure of a first transparent resin layer 3 in which an ultraviolet absorbing agent is dispersed in a resin. An ultraviolet absorbing agent may also be added or dispersed in the light scattering functional portion.

A transparent resin layer can be laminated on the black matrix substrate 110 so as to cover the light-reflective matrix 5. The thickness of the transparent resin layer can be important when the black matrix substrate of the present invention is applied to a liquid crystal display device.

The direction indicated by the arrow C in FIG. 1 indicates the direction of irradiation of light from a light source which is a light emitting element such as an LED.
1(d) is an enlarged view and a cross-sectional view of the light-reflective matrix 5. On the second black matrix layer 4, two layers are laminated: a metal thin film 6 of titanium or titanium nitride, and a thin film 7 of aluminum or an aluminum alloy. The film thicknesses of these metal thin films 6 and 7 are not limited. For example, the metal thin film 6 can be formed to a thickness of 100 nm to 300 nm, and the thin film 7 can be formed to a thickness of 10 nm to 40 nm.

Figure 1(c) is an enlarged view of the first black matrix layer 1 formed on the transmittance adjusting layer 2. Figure 3 is a plan view of Figure 1(b) seen from direction C (from the light-reflecting matrix 5). The scattering film 10 is not shown.

Example 2
FIG. 2A is a cross-sectional view of a black matrix substrate 120 according to the second embodiment.
As in the first embodiment, the black matrix substrate 120 has a structure in which a transmittance adjusting layer 2, a first black matrix layer 1, and a light scattering layer 10 are laminated in this order on a transparent substrate 100, a second black matrix layer 4, and a light reflective matrix 39 is laminated on the second black matrix layer 4. The light scattering layer 10 has a light scattering function of dispersing transparent particles 8 in a transparent resin. The light scattering layer 10 can have a two-layer structure of a first transparent resin layer 3 in which an ultraviolet absorbing agent is dispersed in a resin. An ultraviolet absorbing agent may also be added or dispersed in the light scattering functional portion.

The light-reflective matrix 39 shown in the partially enlarged view of FIG. 2(b) has a three-layer structure of a first conductive oxide thin film 36, a silver or silver alloy thin film 37, and a second conductive oxide thin film 38 on the second black matrix layer 4. The first conductive oxide and the second conductive oxide are conductive oxides containing 50 wt % or more of indium oxide. The first conductive oxide and the second conductive oxide may have respective thicknesses in the range of 10 nm to 60 nm, but may be greater than 60 nm. The first conductive oxide and the second conductive oxide may have respective thicknesses different from each other. The thickness of 37 may be in the range of 100 nm to 300 nm, but may be greater than 300 nm. The silver or silver alloy thin film has a higher reflectance than the aluminum thin film, and can be preferably used.
The first conductive oxide and the second conductive oxide may be composite oxides containing metal oxides such as zinc oxide, tin oxide, antimony oxide, and titanium oxide in addition to indium oxide.
In the second embodiment, the above-mentioned black matrix substrate of the present invention is applied to a display device such as an LED display, a liquid crystal display device, etc. Examples 3 and 4 of the second embodiment will be described in detail below.

Example 3
This embodiment will be described with reference to Figures 5, 7 and 9. Figure 5 is a cross-sectional view of an LED display formed by bonding together the black matrix substrate 110 of the first embodiment and the array substrate 210 on which red LEDs 21, green LEDs 22 and blue LEDs 23 are mounted, so as to face each other. The black matrix substrate 110 and the array substrate 210 are bonded together, for example, via a silicone-based resin.

The array substrate 210 with the matrix arrangement of light-emitting units may be referred to as an optical module in the following description. Each light-emitting unit includes multiple light-emitting elements, which are red LEDs 21, green LEDs 22, and blue LEDs 23.

In Example 2, the total number of light-emitting elements is 1/3 of the total number of pixels, and is arranged according to the pixel pitch. At least two thin-film transistors are arranged in each pixel. The light-emitting elements (red LED 21, green LED 22, blue LED 23) can be divided by partitions 28 or the like. The light from the light-emitting elements that hits the light-reflective matrix 5 is reflected on the light source (light-emitting element) side and reused.

Each light-emitting element can have a structure as shown in FIG. 7. For example, a blue LED 23 is mounted on a reflective electrode 18 via a lower electrode 17. The upper electrode 16 of the blue LED 23 is connected to the LED common electrode via a contact hole 15. Note that the mounting of such light-emitting elements may use other mounting techniques such as wire bonding using gold or aluminum wires, instead of the configuration shown in FIG. 7. An array substrate on which light-emitting elements (red LED 21, green LED 22, blue LED 23) are arranged is called an optical module. For example, the technology proposed in this invention has the flexibility to provide a variety of display devices by combining a black matrix substrate with optical modules of different specifications.

In FIG. 7, the thin-film transistors are disposed on the fourth insulating layer 41, but are omitted from FIG. 7. FIG. 9 is an equivalent circuit diagram in which a light-emitting element 40 (corresponding to any one of the red LED 21, green LED 22, and blue LED 23) is driven by two thin-film transistors. Of the two thin-film transistors, the selection transistor 45 receives a selection signal from the gate line G9 and a video signal from the source line S9, and drives the drive transistor 46. The drive transistor 46 supplies a current from the power line VD7 to the light-emitting element 40 to cause it to emit light. In Example 4 described below, instead of driving each individual light-emitting element, the drive may be performed with different brightness for each light-emitting unit or for each light-emitting color within the light-emitting unit.

Since the first black matrix 1 and the light-reflective matrix 5 (and the second black matrix 4) are positioned to face each other in the thickness direction of the scattering film 10, the influence of stray light on adjacent pixels can be suppressed. In other words, the oblique light incident on adjacent pixels can be reduced. For example, the light Gc emitted in the direction of the opening shown in FIG. 5 is emitted as is from the green LED 22. However, the light GL, GR heading toward the adjacent pixels is cut by the light-reflective matrix 5, and the influence on the adjacent pixels can be eliminated.
The thickness of the scattering film 10, the line width (or pixel aperture ratio) of the black matrix 1, the thickness of the scattering film 10, and the scattering particle density are appropriately adjusted depending on the overall size and use of the LED display. A cover glass, a touch panel, and even an antenna for charging and communication may be mounted on the LED display.

Example 4
A fourth embodiment will be described with reference to FIGS. 6, 7 and 8.
FIG. 6 shows a liquid crystal display device 700 in which the black matrix substrate 110 described in the first embodiment is bonded to the array substrate 310 via the liquid crystal layer 30, and an optical module 510, which is a backlight unit, is disposed below the liquid crystal panel 710. Here, the liquid crystal panel 710 refers to a configuration that does not include the optical module 510. In the array substrate 310, at least one thin film transistor for driving the liquid crystal is connected to each pixel electrode 26. The liquid crystal layer 30 is of the FFS (fringe field switching) type that is driven by the fringe electric field between the pixel electrode 26 and the common electrode 17. The liquid crystal is not limited to FFS, and may be VA (vertically aligned) or other liquid crystal. FIG. 7 is a partial enlarged view of the optical module 510 having a plurality of light-emitting units 24.

The light-emitting unit 24 is partitioned by partitions 28 and includes multiple red LEDs 21, green LEDs 22, and blue LEDs 23 within the light-emitting unit 24. The multiple red LEDs 21, green LEDs 22, and blue LEDs 23 within the light-emitting unit 24 emit light with the intensity of red, green, and blue adjusted according to the color and brightness to be displayed within the light-emitting unit. For individual driving of the light-emitting units, it is preferable that each light-emitting unit is driven by a thin-film transistor. The multiple red LEDs 21, green LEDs 22, and blue LEDs 23 within one light-emitting unit can be driven collectively by color.

Although FIG. 7 is simplified for the purpose of explanation, the number of red LEDs 21, green LEDs 22, and blue LEDs 23 (or the number of blue LEDs 25) in the light-emitting unit 24 is not limited to a total of three. Local dimming is performed in units of light-emitting units 24, but the number of pixels targeted for local dimming at this time can be several hundred to several thousand, and this does not limit the number of pixels. The more the number of targeted pixels, the lower the cost of forming the light-emitting unit. The number, arrangement position, and size of the red LEDs 21, green LEDs 22, and blue LEDs 23 (or the number of blue LEDs 25) are adjusted so that the pixels targeted for local dimming are displayed uniformly within the section. The mounting means of the light-emitting elements is also not limited, and may be mounted by flip chip bonding, wire bonding, or anisotropic conductive film means. In the figure, the LED common electrode 14 is connected to the upper electrode through a contact hole 15 as shown in FIG. 7. If the red LED 21, green LED 22, and blue LED 23 have different thicknesses, this can be adjusted by adjusting the depth of the contact holes and the thickness of the lower electrodes, etc.

In general, LED light-emitting elements have an active layer 47, which serves as a light-emitting layer, between the n-type semiconductor layer and the p-type semiconductor layer of each of the red LED 21, green LED 22, and blue LED 23 in FIG. 7. Most of the light emitted by the active layer 47 is emitted upward through the upper electrode. At this time, some of the light is emitted from the active layer 47 in the lateral direction as shown in the figure. To effectively use the lateral light 48, it is preferable to place transparent particles 8 near the active layer 47. The light scattered by the transparent particles 8 is reflected by the reflective electrode 18 and the partition wall 28 and utilized.

Although the thin film transistor is not shown in FIG. 6, the thin film transistor is disposed on the first insulating layer.
Fig. 8 is an equivalent circuit diagram of a liquid crystal drive using the array substrate 310 in the liquid crystal panel 710 portion. In the equivalent circuit diagram of Fig. 8, one pixel electrode 26 is electrically connected to one thin film transistor 44, and the liquid crystal layer 30 shown in the liquid crystal display device 710 of Fig. 6 is driven by the thin film transistor provided on the array substrate 310. Upon receiving a video signal from the source line S and a selection signal from the gate line G8, a liquid crystal drive voltage is applied to the pixel electrode 26, and the liquid crystal layer 30 is driven. Note that the formation of the auxiliary capacitance CS8 and the auxiliary capacitance line CS may be omitted.
The third embodiment can provide a simple liquid crystal display device that can omit the color filter and the wavelength conversion layer.

The display device having the black matrix substrate according to the above-mentioned embodiment can be used in various applications. Examples of electronic devices to which the display device according to the above-mentioned embodiment can be applied include electronic devices such as mobile phones, portable game devices, portable information terminals, personal computers, electronic books, video cameras, digital still cameras, head-mounted displays, navigation systems, audio playback devices (car audio, digital audio players, etc.), copiers, facsimiles, printers, printer-combination devices, vending machines, automated teller machines (ATMs), personal authentication devices, optical communication devices, and IC cards. The above-mentioned embodiments can be used in any combination. It is desirable that an antenna is further installed in an electronic device equipped with a display device according to the embodiment of the present invention to perform communication and contactless power reception and supply.

While preferred embodiments of the present invention have been described and illustrated above, it should be understood that these are illustrative of the present invention and should not be considered as limiting. Additions, omissions, substitutions, and other modifications can be made without departing from the scope of the present invention. Thus, the present invention should not be considered as limited by the foregoing description, but is defined by the claims.

REFERENCE SIGNS LIST 1: First black matrix layer 2: Transmittance adjusting layer 3: First transparent resin layer 4: Second black matrix layer 5, 39: Light reflective matrix (metal thin film)
Reference Signs List 6 titanium or titanium nitride metal thin film 7 aluminum or aluminum alloy thin film 8 transparent particles 9 second transparent resin layer 10 light scattering layer 14 LED common electrode 15 contact hole 16 upper electrode 17 lower electrode 18 reflective electrode 19 pixel opening 20 observer 21 blue LED
22 ...Green LED
23...Red LED
24 ... Light-emitting unit 26 ... Pixel electrode 27 ... Common electrode 28 ... Partition wall 29 ... Prism sheet 30 ... Liquid crystal layer 31 ... First polarizing plate 32 ... Second polarizing plate 33 ... First insulating layer 34 ... Second insulating layer 35 ... Third insulating layer 36 ... First conductive oxide thin film 37 ... Silver or silver alloy thin film 38 ... Second conductive oxide thin film 40 ... Diode (LED)
41: Fourth insulating layer 42: Fifth insulating layer 43: Sixth insulating layer 44: Thin film transistor 45: Selection transistor (thin film transistor)
46...Drive transistor (thin film transistor)
47: Active layer 48: Lateral light 50: Liquid crystal panel 51: Blue LED
52 ... Diffusion plate 53 ... Wavelength conversion sheet 54 ... Prism sheet 100 ... Transparent substrate 110, 120 ... Black matrix substrate 200 ... Second substrate 210 ... Array substrate 300 ... Third substrate 310, 320, 330 ... Array substrate 400 ... Fourth substrate 410, 510 ... Optical module 500 ... Fifth substrate 600, 610 ... LED display 700 ... Liquid crystal display device 710 ... Liquid crystal panel 800 ... Conventional liquid crystal display device 900 ... Display function layer Ax, Ay ... Line width of first black matrix Bx, By ... Line width of light reflection matrix Cx, Cy ... Line width of second black matrix c-LED ... Light-emitting element B directly below c pixel ... Irradiation direction of light from light source L1, L2, L3, L4, L5, L6, L7 ... Light (incident light, reflected light, stray light, etc.)
LB1: Reflectance in the transparent substrate, transmittance adjustment layer, and first black matrix configuration LB2: Reflectance in the transparent substrate and first black matrix configuration CS: Storage capacitance line CS8: Storage capacitance VD7: Power supply line G8, G9: Gate lines S8, S9: Source line P1: P1 pixel P2: P2 pixel (adjacent pixels)

Claims (13)

On one surface of the transparent substrate,
a transmittance adjusting layer which is a dispersion of carbon black, transparent fine particles, and a resin ;
a first black matrix including a plurality of openings defined by a line width Ax in a first direction and a line width Ay in a second direction in a plan view;
a light scattering layer covering the plurality of openings and the first black matrix;
a second black matrix on the light scattering layer, the second black matrix being partitioned so as to overlap with the center of the line width Ax and the center of the line width Ay of the first black matrix, the second black matrix having a plurality of openings partitioned by a line width Bx in a first direction and a line width By in a second direction;
a light-reflecting matrix having a plurality of openings, which are partitioned on the second black matrix so as to overlap at the center of the line width Bx and the center of the line width By, and which are partitioned by a line width Cx in a first direction and a line width Cy in a second direction;
The line width Ax, the line width Cx, the line width Ay, and the line width Cy are related by the following formulas (1) and (2):
Black matrix substrate.
Ax>Bx≧Cx・・・(1)
Ay>By≧Cy・・・(2) The light scattering layer is a light scattering layer containing transparent particles.
The black matrix substrate according to claim 1 . The light-scattering layer is a light-scattering layer containing zinc oxide particles.
The black matrix substrate according to claim 1 . The light-scattering layer is a light-scattering layer containing carbon black and a blue pigment.
The black matrix substrate according to claim 1 . The light scattering layer is a light scattering layer containing an ultraviolet absorber.
The black matrix substrate according to claim 1 . the light-reflective matrix is configured by laminating a thin film of titanium or titanium nitride and a thin film of an aluminum alloy containing neodymium on the second black matrix in a two-layer configuration;
The black matrix substrate according to claim 1 . the light-reflective matrix is configured to have a three-layer structure including a first conductive oxide thin film, a silver or silver alloy thin film, and a second conductive oxide thin film laminated on the second black matrix;
The black matrix substrate according to claim 1 . a first transparent resin layer is inserted between the light scattering layer and the second black matrix;
The black matrix substrate according to claim 1 . A second transparent resin layer is laminated on the light-reflective matrix.
The black matrix substrate according to claim 1 . A black matrix substrate according to any one of claims 1 to 8 ,
at least,
A display function layer;
A display device comprising: The display function layer is a red light emitting element, a green light emitting element, and a blue light emitting element, each of which is driven by a thin film transistor.
The display device according to claim 10 . The display function layer is a red light emitting diode, a blue light emitting diode, and a green light emitting diode, each of which is driven by a thin film transistor.
The display device according to claim 10 . 11. The display device according to claim 10 , wherein the display function layers are liquid crystal layers driven by thin film transistors, and the display device comprises a backlight unit including a plurality of optical modules each including a red light emitting diode, a blue light emitting diode, and a green light emitting diode.