JP2003172927A - Substrate for transmission and reflection type display unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To freely adjust only a color tone in transmission display without impairing a color tone in reflection display and to obtain excellent color tones in the transmission display and reflection display. <P>SOLUTION: A metal thin film (reflecting layer) 8A has an opening area 101 which transmits light in the transmission display and a reflection area 102 which totally reflects the light. A reflecting layer 8A in the reflection area 102 totally reflects the external light, so the external light reaching the reflection area 102 of the reflecting layer 8A is all reflected by the reflecting layer 8A and no reflection is caused on the interface between a light diffusion layer 7A and a lower substrate 2. On the top surface of the reflecting layer 8A, a color layer (color filter) 9 is formed, so at least the light diffusion layer 7A in the opening area 101 is colored and the chromaticity of the colored light reflecting layer 7A is adjusted to adjust only the color tone in the transmission display. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate for a transflective display device. The substrate of the present invention performs reflective display by reflecting incident light from the outside (hereinafter, also referred to as outside light), and transmits light from a light source such as a backlight when the outside is dark. It can be used for a transflective display device that performs transmissive display.

[0002]

2. Description of the Related Art With the recent innovative development of IT technology,
The amount of information used in mobile information terminals such as mobile phones has remarkably increased, and the applications of mobile information terminals have been diversified. Along with this, users' demands for displays of personal digital assistants are diversifying, and not only low voltage but also high definition and high-speed response are wide-ranging. As for the display color of the display, the number of colors increases at an accelerated rate, and the demand for color tint also diversifies, and it is essential to realize the tint of reflective display and transmissive display that each user desires. is there. In addition, since the color tones requested by each user have different visibility depending on the observer, almost all of them are currently different.

At present, a transflective liquid crystal display device is widely used as a display used in a portable information terminal. The transflective liquid crystal display device operates as a reflective liquid crystal display device using outside light in a bright place and operates as a transmissive liquid crystal display device using a light source in a dark place.

An example of the transflective liquid crystal display device is a transflective liquid crystal display device using a semitransparent metal thin film made of aluminum or the like. The semi-transparent metal thin film has both a transmission function and a reflection function of transmitting light from the backlight and reflecting external light in a dark place. Further, in order to improve the light diffusibility, a light transmission layer having a fine concavo-convex structure and made of, for example, a light transmission resin may be provided, and the metal thin film may be formed on the light transmission layer. This improves the diffusivity of reflected light, prevents so-called blurring of characters and color mixing during color display, and improves display visibility. A light-transmitting layer having a fine uneven structure (uneven surface) does not diffuse light by itself, but by forming a reflecting layer on the uneven surface of the light-transmitting layer, the reflected light is diffused. Then, the light transmitting layer having a fine uneven structure (uneven surface) is also referred to as a “light diffusing layer”.

By the way, when a metal thin film is used as the semi-transmissive film, the transmitted light has a unique tint. For example, in the case of an aluminum thin film, the transmitted light has a bluish tint, so that there is a problem in that white in transmissive display is bluish. It is considered that the reason is that the light on the short wavelength side of the light source easily transmits through the metal thin film, but the light on the long wavelength side hardly transmits. In any case, if the transmitted light is bluish, the color purity in color display is reduced.

The color correction during the transmissive display can be performed by the color filter itself, for example. But,
Since external light is transmitted through the color filter twice during reflective display, the color tone correction during transmissive display greatly affects the color during reflective display, and the color purity during reflective display is reduced, which is not preferable. Further, by attaching a color correction filter to the substrate located on the backlight side, it is possible to correct only the color tone during transmissive display. However, if the liquid crystal display device is stored under high temperature and high humidity conditions, the color correction filter may be discolored or discolored due to the influence of moisture, which causes a problem in reliability. Furthermore, when coloring the polarizing plate,
Since the degree of polarization of the light passing through the polarizing plate is lowered, there is a problem that the contrast is lowered.

In order to solve such a problem, in a semi-transmissive liquid crystal display device using a semi-transmissive metal thin film, a technique for coloring the light diffusing layer and performing color correction during transmissive display is disclosed. No. 2001-100197. The technique disclosed in Japanese Patent Laid-Open No. 2001-100197 will be described below.

The liquid crystal display device disclosed in the publication has a pair of transparent electrode substrates which are pressure-bonded via a peripheral sealing material so that a predetermined cell gap is formed, and a liquid crystal layer is enclosed in the cell gap. A semi-transmissive type that includes a light diffusion layer made of a light-transmissive resin on the inner surface side of the one transparent electrode substrate, and a light semi-transmissive metal thin film is formed as a light reflection film on the light diffusion layer. The liquid crystal display device is characterized in that the translucent resin of the light diffusion layer is colored in a color having a complementary color relationship with the transmitted light color of the metal thin film. For example, when aluminum is used as the light semi-transparent metal thin film,
Since the transmitted light is bluish, the tint of the transmitted light is corrected to white by coloring the resin light diffusion layer in yellow which is a complementary color to blue.

A more specific description will be given with reference to FIG. The liquid crystal display device described above includes an upper substrate 1 and a lower substrate 2 which are pressure-bonded to each other via a peripheral sealing material. The retardation plate 21 A and the polarizing plate 22 are provided on the outer surface of the upper substrate 1.
A is provided, and a retardation plate 21B and a polarizing plate 22B are provided on the outer surface of the lower substrate 2. A backlight is provided on the lower substrate 2 side.

On the inner surface of the lower substrate 2, a light diffusion layer 7A and a light semi-transparent metal thin film 8B as a light reflection film are formed. The light diffusion layer 7A is made of a translucent resin, and fine irregularities are formed on the surface thereof.

When aluminum is used for the light semi-transmissive metal thin film 8B, the transmitted light color is blue,
In order to correct the color of the transmitted light, the light diffusion layer 7A is colored in yellow which is a complementary color of blue in advance. In this semi-transmissive liquid crystal display device, the light emitted from the backlight is transmitted to the yellow-colored light diffusion layer 7A and the light semi-transmissive metal thin film 8B to reach the upper substrate 1 side which is the display surface. Reach Since yellow is in a complementary color relationship with blue, the light emitted from the backlight is color-corrected when passing through the metal thin film 8B and can illuminate the display surface as almost white light.

On the other hand, during reflective display using external light, since the external light is reflected by the metal thin film 8B, there is little difference in color between when the backlight is used and when the external light is used, and a sense of discomfort is felt. It is described in the same publication that the display without the above is obtained.

[0013]

By the way, when the semi-transmissive metal thin film 8B is used as the metal thin film of the semi-transmissive liquid crystal display device, the reflective layer formed of the metal thin film 8B naturally transmits light. You can When the display is performed by reflection by the external light, the external light is reflected by the polarizing plate 22 as shown in FIG.
After passing through A and the retardation plate 21A and passing through the upper substrate 1, the transparent electrodes 3, 4, the alignment films 5, 6, and the liquid crystal layer 12, the metal thin film 8B is reached. The light reaching the metal thin film 8B is decomposed into light C reflected on the surface of the metal thin film 8B and light transmitted through the metal thin film 8B. Further, the light transmitted through the metal thin film is reflected light D at the interface between the metal thin film 8B and the light diffusion layer 7A made of transparent resin, and the light diffusion layer 7A and the lower layer (lower substrate 2).
Is decomposed into reflected light E at the interface and transmitted light. Therefore, the light visually recognized on the display surface during the reflective display includes the reflected light C on the metal thin film 8B, the metal thin film 8B, and the light diffusion layer 7.
The reflected light D at the interface A and the reflected light E at the interface between the light diffusion layer 7A and the lower layer (lower substrate 2) become light of a combined color.

When coloring the light diffusing layer of the liquid crystal display device using the semi-transmissive metal thin film 8B, the light diffusing layer 7A effectively acts as a color correction during the transmissive display by the backlight light. However, as described above, some of the light colored by the light diffusion layer 7A is reflected during the reflective display, so that the light diffusion layer 7A also affects the chromaticity during the reflective display. Further, when a metal such as aluminum or silver-palladium is used as the metal thin film, the transmitted light is tinged with blue, while the reflected light is tinged with a complementary color of yellow, so that the reflective display is slightly yellowed. Therefore, when the light-diffusing layer is colored with a blue complementary color (yellow) tinged with light transmitted through the metal thin film 8B, the complementary color is the same color as the reflected light of the metal thin film 8B, and therefore, the light-diffusing layer 7A is colored during reflection display. Further, the display color becomes yellowish. That is, there is a problem that adjusting the color tone during transmissive display impairs the tint during reflective display as a trade-off.

Further, regarding the color tone at the time of transmission and reflection display, not only the tint of the metal thin film 8B but also the color of all the laminated films such as the ITO film and the alignment film through which the transmitted light and the reflected light are transmitted and the color of the lower substrate 2. It is a combination of degrees. Since the ITO film and the alignment film are slightly colored, the display color is affected by the color of the laminated film such as the ITO film and the alignment film which are colored. Therefore, the adjustment of the color tone is insufficient only by coloring the light diffusion layer with the complementary color of the metal thin film 8B.

When a plastic substrate is used as the lower substrate 2, the plastic substrate is more strongly colored than the glass substrate. Therefore, by simply coloring the light diffusing layer with a complementary color of the metal thin film 8B, it is possible to perform reflection and display at the time of transmission display. Both color corrections at the time of display are virtually impossible.

The present invention has been completed in view of the above problems, and an object thereof is to freely adjust only the color tone in the transmissive display without impairing the color tone in the reflective display, and to provide the transmissive display. It is an object of the present invention to provide a substrate for a transflective display device which satisfies both a good color tone at the time of display and at the time of reflective display.

[0018]

According to a first aspect of the present invention, there is provided a transflective type display device substrate, wherein a light transmission layer for transmitting light is formed on the substrate, and a reflection region for totally reflecting the light and a light region. Is formed on the light transmitting layer, and the light transmitting layer in at least the opening region is colored.

According to the substrate for a transflective display device according to the first aspect of the present invention, the transmitted light due to the light from the light source such as the backlight is transmitted only through the opening region of the reflective layer. The tint is determined only by the light transmitted through the opening region, and it is not necessary to consider the chromaticity of the light transmitted through the reflective region of the reflective layer. Therefore, by coloring the light transmission layer at least in the opening region, the color tone during transmissive display can be freely adjusted.

Further, since the reflection layer in the reflection area totally reflects the external light, during reflection display, all the external light reaching the reflection area of the reflection layer is reflected by the reflection layer, and the semi-transmissive reflection layer is used. There is no reflection at the interface between the light transmitting layer and the lower substrate, which occurs when it is exposed. Therefore, not only in the opening region but also in the reflective region, the colored light transmitting layer does not affect the color tone during reflective display. According to the present invention, only the color tone during transmissive display can be adjusted independently without affecting the color tone during reflective display.

In this specification, "transmitting light" means transmitting most of the incident visible light, and also includes the case where a part of the incident light is reflected. "Totally reflect light" means that the transmittance of visible light is almost 0% and almost 100% of incident visible light is reflected.

In the substrate for a transflective type display device according to the first aspect of the present invention, the chromaticity of the colored light transmitting layer is three chromaticity coordinates (0.3) in the XYZ display system.
5, 0.39), (0.29, 0.28) and (0.
27, 0.31).

The chromaticity of the light transmitting layer is three chromaticity coordinates (0.35, 0.39), (0.29,
(0,28) and (0.27,0.31) are included in the triangular area so that the light-transmitting layer is colored to improve the contrast, transmittance, and color reproducibility during transmissive display. It is possible to realize an excellent, bright and favorable white transmissive display.

In the transflective type display device substrate according to the second aspect of the present invention, a light transmission layer for transmitting light is formed on the substrate, and a reflection region for totally reflecting light and an opening region for transmitting light are provided. A reflective layer having is formed on the light transmitting layer, and at least the light transmitting layer in the opening region is
It has a function of coloring the light transmitted through the light transmitting layer.

According to the transflective dual-use display device substrate according to the second aspect of the present invention, the color tone during transmissive display can be freely set, as in the transflective dual-use display device substrate according to the first aspect of the present invention. Can be adjusted to. In order to color the light transmitted through the light transmitting layer, the light transmitting layer itself may be colored. Even when the light transmitting layer is not colored, the transmitted light can be colored by adjusting the refractive index n or the film thickness of the light transmitting layer. This is because interference occurs for each wavelength depending on the refractive index n and the film thickness of the light transmitting layer, so that the color of light of a specific wavelength in white light disappears.

In the substrate for transmissive / reflective display device according to the second aspect of the present invention, the light transmission layer has chromaticity (x1, y1) of light incident on the light transmission layer. If the chromaticity of the light emitted from is (x2, y2),
It is preferable to have a function of setting each of x2-x1 and y2-y1 to be 0.01 or more. As a result, sufficient coloration can be recognized by visual evaluation.

In the transflective type display device substrate according to the second aspect of the present invention, it is preferable that at least the light transmission layer in the opening region has a refractive index n of 2.0 or more. The thickness of the light transmission layer is preferably 20 nm or more and 60 nm or less. This allows the transmitted light to be close to white light when the light transmitted through the light transmission layer in the opening region is bluish due to the substrate or the like.

In the transflective display device substrate according to the first and second aspects of the present invention, a layer having a refractive index smaller than that of the light transmitting layer is formed on the light transmitting layer in the opening region. Is preferred.

In the opening area of the reflective layer, the reflectance is much lower than that in the reflective area of the reflective layer, and black is displayed in effect. It has almost no effect on the color tone. However, as shown in FIG. 2, in the opening region 101 of the reflective layer 8A, most of the light is transmitted through the light transmission layer 7A, but the reflected light A on the light transmission layer 7A, the light transmission layer 7A, and the substrate 2 are reflected. Since the reflected light B is slightly generated at the interface of, the chromaticity at the time of reflective display may be slightly affected.

By making the refractive index of the light transmitting layer in the opening region larger than the refractive index of the film formed directly on the light transmitting layer, the light transmitting layer at the time of reflective display and the film formed directly on the reflective display are formed. The reflected light A at the interface is positively increased, and the external light transmitted through this interface is reduced to suppress the change in chromaticity due to the colored reflected light B at the interface between the light transmission layer and the substrate. Therefore, it is possible to independently adjust only the chromaticity during the transmissive display without affecting the chromaticity during the reflective display.

In the transflective display device substrate according to the first and second aspects of the present invention, a colored layer may be formed on the light transmissive layer and the reflective layer in the opening region. The colored layer is formed on the light transmission layer and the reflection layer in the opening region directly or via another film.

In the substrate for a transflective display device according to the first and second aspects of the present invention, it is preferable that the reflective layer has a fine uneven structure. Since the reflective layer has a fine concavo-convex structure, the diffusibility of external light is improved, so that so-called blurring of characters and color mixing at the time of color display can be prevented, and the visibility of display can be improved.

The transflective liquid crystal display device of the present invention comprises:
It has a substrate for transmissive / reflective display device of the present invention, a counter substrate facing the substrate for transmissive / reflective display device, and a liquid crystal layer interposed between the both substrates. According to the transflective liquid crystal display device of the present invention, it is possible to switch between reflective display and transmissive display.

The electronic equipment of the present invention comprises the transflective liquid crystal display device of the present invention as a display section. Since the electronic device of the present invention does not need to turn on a lighting device such as a backlight in a bright place, it can be driven by a battery for a long time. Further, in a dark place, bright and excellent white transmissive display can be realized, and thus there is an advantage that the visibility is very good.

[0035]

DETAILED DESCRIPTION OF THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. In the following embodiments, the case where the transflective dual-use display device substrate of the present invention is used as a transflective dual-use liquid crystal display device substrate, the transflective dual-use display device substrate of the present invention is a liquid crystal. The substrate is not limited to the display device. As an example of the liquid crystal display device, an STN liquid crystal display device of a simple matrix drive system is taken as an example.
in Film Transistor: MIM (Met)
It is also applicable to an active matrix drive system using a switching element such as al-Insulator-Metal), other segment type devices, and other liquid crystal devices. Further, in the first embodiment, a light diffusion layer having a fine concavo-convex structure will be described as an example of the light transmission layer that transmits light. However, the light transmission layer has a flat surface in contact with the reflection layer, and thus has a light diffusion property. You do not have to have it.

(Embodiment 1) FIG. 1 is a sectional view schematically showing the structure of a liquid crystal display device of Embodiment 1, and FIG.
It is a cross-sectional enlarged view which shows the one pixel schematically. The configuration of the liquid crystal display device of the present embodiment will be described with reference to FIGS. 1 and 2.

In the liquid crystal display device of this embodiment, the liquid crystal layer 12 is sealed by the frame-shaped sealing material 11 between the two transparent substrates 1 and 2 facing each other. The liquid crystal layer 12 is
It is composed of nematic liquid crystal having a twist angle of 240 ° to 260 °. A light diffusion layer 7A colored in an arbitrary color is formed on a transparent substrate (hereinafter, also referred to as a lower substrate) 2 on the side opposite to the observer side.

On the upper surface of the light diffusion layer 7A, for example, Al, P
A metal thin film made of d, Ag, or an alloy of these metals is formed. The film thickness of the metal thin film is set so that the light transmittance is almost 0%, and the metal thin film is the reflective layer 8A that totally reflects light. For example, when an alloy of silver and palladium (Ag-Pd) is used as the metal thin film, the film thickness is set to 1000 Å (100 nm) or more.

On the metal thin film (reflection layer) 8A, there are provided opening regions 101 R (red), G (green), and B for exposing light during transmissive display.
It is provided for each (blue) pixel. Display can be performed by transmitted light from the opening region 101 during transmissive display, and by reflected light at the reflective region 102 where the metal thin film (reflection layer) 8A is present during reflective display.
The area ratio between the opening region 101 and the reflection region 102 is 2
It is preferably 5:75 to 80:20, and is set to 3: 7, for example.

R (red), G (green), B are formed on the upper surface of the total reflection metal thin film (reflection layer) 8A having the opening region 101.
Colored layers (color filters) 9 of three colors (blue) are formed in a predetermined pattern. A transparent protective film 10 is formed on the upper surface of the colored layer 9, and a plurality of stripe-shaped transparent electrodes 4 are formed of an ITO film or the like on the upper surface of the protective film 10. An alignment film 6 is formed on the upper surface of the transparent electrode 4.
Are formed, and the alignment treatment is performed in a predetermined direction by rubbing or the like.

On the other hand, a plurality of stripe-shaped transparent electrodes 3 are formed on the upper surface of a transparent substrate (hereinafter, also referred to as an upper substrate) 1 facing the lower substrate 2 on the side of an observer. An alignment film 5 is formed on the upper surface, and an alignment treatment is performed in a predetermined direction by rubbing or the like.

As the transparent substrates 1 and 2, glass substrates such as float glass and soda glass, and plastic substrates such as polyether sulfone, polycarbonate, epoxy resin and polyethylene terephthalate can be used.

The method of coloring the light diffusing layer is not particularly limited, and examples thereof include a method of dispersing a pigment in a transparent resin. As the pigment dispersed in the light diffusion layer 7A,
For example, there are inorganic pigments such as yellow lead, red iron oxide, ultramarine blue, and navy blue, and organic pigments shown below by color index (CI) numbers.

Yellow pigment: C.I. I Pigment Yellow 2
0, C.I. I pigment yellow 24, C.I. I pigment yellow 83, C.I. I pigment yellow 86, C.I. I
Pigment Yellow 93, C.I. I Pigment Yellow 1
09, C.I. I pigment yellow 110, C.I. I pigment yellow 117, C.I. I Pigment Yellow 12
5, C.I. I pigment yellow 137, C.I. I pigment yellow 138, C.I. I Pigment Yellow 139,
C. I pigment yellow 147, C.I. I pigment yellow 148, C.I. I pigment yellow 153, C.I.
I pigment yellow 154, C, I pigment yellow 166, C.I. I Pigment Yellow 168

Blue pigment: C.I. I Pigment Blue 15,
C. I pigment blue 22, C.I. I pigment blue 60, C.I. I Pigment Yellow 64

The color for coloring the light diffusion layer 7A is arbitrary,
In addition to the above yellow pigment and blue pigment, an orange pigment, a red pigment, a green pigment and the like can be used. Since the light diffusion layer can be colored by dispersing the pigment in the light diffusion layer, the manufacturing process of the conventional semi-transmissive liquid crystal display device can be used as it is, and the color can be obtained without increasing the manufacturing cost. You can adjust the degree. Furthermore, since the totally reflective metal thin film (reflection layer) 8A is formed in the reflection area 102 on the light diffusion layer 7A, the colored light diffusion layer 7A affects the color tone during reflective display. Absent. Therefore, the chromaticity during transmissive display can be adjusted independently.

The light diffusing layer 7A is the opening area 1 of the reflecting layer 8A.
It is sufficient that at least the portion corresponding to 01 is colored, and it is not always necessary to color the entire light diffusion layer 7A. However, the portion of the reflective layer 8A corresponding to the reflective region 102 may be colored. Reflection area 1 of the reflection layer 8A
Even if the light diffusion layer 7A corresponding to No. 02 is colored, the reflection layer 8A in the reflection region 102 totally reflects the light and does not transmit the light, and thus does not affect the color tone during transmissive display. Rather, forming the light diffusion layer 7A that is entirely colored has the advantage of being easier to manufacture than forming the light diffusion layer 7A that is partially colored. Light diffusion layer 7A
The photolithography method or the printing method may be employed to partially color the.

In this embodiment, the color filter (coloring layer) 9 is formed on the lower substrate 2, but it is not particularly limited and may be formed on the upper substrate 1.

(Second Embodiment) FIG. 10 is a sectional view schematically showing the structure of a liquid crystal display device according to the second embodiment. In addition,
In FIG. 10, components having substantially the same functions as those of the liquid crystal display device of Embodiment 1 are indicated by common reference numerals,
The description is omitted. In the first embodiment, the light diffusion layer 7
Although A is colored, the light diffusion layer 7B of this embodiment is
It is transparent with no color.

The liquid crystal display device of the present embodiment has the light diffusion layer 7
It has a light transmission layer 7C formed between B and the reflection layer 8A. For the light transmitting layer 7C, a thin film having a large refractive index such as a TiO ₂ film is used. The light transmission layer 7C has a function of coloring transmitted light. The hue of light colored by the light transmitting layer 7C is determined by the refractive index and the film thickness of the light transmitting layer 7C. Light incident on the light transmitting layer 7C from a light source (not shown) is transmitted through the light transmitting layer 7C and the colored layer (color filter) 9
A part of the light is emitted to the liquid crystal layer 12 side at the interface with and a part is reflected. At the interface between the light transmission layer 7C and the light diffusion layer 7B, a part of the reflected light is again emitted to the light source side and a part thereof is reflected. Since a part of this reflected light is emitted to the liquid crystal layer 12 side beyond the interface between the light transmission layer 7C and the coloring layer 9, it is transmitted without being reflected at the interface between the light transmission layer 7C and the coloring layer 9. Interferes with light. Due to this interference effect, the light transmitted through the light transmission layer 7C is colored.

In order to color the transmitted light more intensely by the interference effect, more light is reflected at the interface between the light transmitting layer 7C and the layer above it (the colored layer 9 in this embodiment), and the light transmitting layer is further reflected. 7C and layers below it (in the present embodiment, the light diffusion layer 7
It is necessary to reflect more light at the interface with B).
In order to reflect more light at these interfaces, it is necessary to make the refractive index of the light transmission layer 7C smaller than the refractive indexes of the upper and lower layers (the colored layer 9 and the light diffusion layer 7B in this embodiment). There is.

The light diffusion layer 7B may be colored. Further, the light diffusion layer 7B can be omitted. The light transmitting layer 7C may be present at least in a portion corresponding to the opening region 101 of the reflective layer 8A, and the reflective region 1 of the reflective layer 8A may be present.
It does not have to exist in the part corresponding to 02.

(Examples and Comparative Examples) With respect to the following Examples and Comparative Examples, the difference in tint between the reflective display and the transmissive display was evaluated.

For the measurement of chromaticity during reflective display, CM-1000 (C light source 2 ° field of view) manufactured by Minolta was used, and R (red) was used.
-The chromaticity at the time of white display was measured with all G (green) and B (blue) ON displays. In addition, for the measurement of chromaticity during transmissive display, T
Using BM-5 made by OPCON, R (red), G (green),
The chromaticity at the time of white display was measured in all ON display of B (blue). The specific chromaticity of the backlight will be described later.

The chromaticity of the light diffusing layer was measured with the light diffusing layer (film thickness 2.5 μm) formed on the lower substrate 2, and the TO
The chromaticity at the time of transmissive display was measured using BM-5 manufactured by PCON.

In Examples 1, 2, 4, 5, and 6 and Comparative Examples 1, 2, and 3, the retardation plate and the polarizing plate bonded to the upper substrate 1 and the lower substrate 2, respectively, had the same axial angle and retardation. System was used. Specifically, as shown in FIGS. 1 and 4, when the clockwise direction is positive and the counterclockwise direction is negative with respect to the alignment direction of the liquid crystal molecules, the axial angle of the first retardation plate 21A is −. 55 ° second retardation plate 21
The first retardation plate 21A, the second retardation plate 21B, and the polarizing plate 22A were sequentially attached to the upper substrate 1 so that the axis angle of B was 80 ° and the axis angle of the polarizing plate 22A was 0 °. The retardations of the liquid crystal layer 12 and the retardation plates 21A and 21B are set to 800 nm for the liquid crystal layer 12 and the first retardation plate 21.
A was 180 nm, and the second retardation plate 21B was 670 nm. Further, as shown in FIG. 5, the retardation plate 21C and the polarizing plate 22B are arranged on the lower substrate 2 so that the axial angle of the retardation plate 21C is −5 ° and the axial angle of the polarizing plate 22B is −52.5 °.
It was pasted in sequence. The retardation of the retardation plate 21C was set to 140 nm.

(Comparative Example 1) The liquid crystal display device of the first embodiment is similar to the liquid crystal display device of the first embodiment except that the colored light diffusion layer 7A is used instead of the colored light diffusion layer 7A. A liquid crystal display device was created (see FIG. 1).

First, on the lower substrate 2, a film transfer type uncolored light diffusion layer 7B made of an acrylic resin manufactured by Hitachi Chemical.
Was formed. At this time, the thickness of the light diffusion layer 7B is 2.5 μm.
Met. A metal thin film made of Ag-Pd was formed by sputtering. A resist is applied on a metal thin film made of Ag-Pd, and exposure and development processing is performed using a photomask so that the area ratio of the reflective region 102 and the opening region 101 is 7: 3, and the opening region 101 is formed. A metal thin film 8A having total reflection property was formed. At this time, the film thickness of the metal thin film 8A is 1
It was 200Å (120 nm).

Next, the light diffusion layer 7 in the opening region 101.
R (red), G (green), B on B and metal thin film 8A
After forming the colored layer (color filter) 9 made of (blue), the protective film 10 was formed on the colored layer 9. The thickness of the colored layer 9 was 0.8 μm. An ITO film (transparent electrode) 4 patterned in a stripe shape is formed on the protective film 10, and further 240 ° is rubbed or the like on the upper surface thereof.
An alignment film 6 made of polyimide that had been subjected to an alignment treatment so as to be twisted was formed.

On the upper surface of the upper substrate 1, an ITO film (transparent electrode) 3 patterned in a stripe pattern is formed, and similarly to the lower substrate 2, a polyimide which is oriented by 240 ° twist by rubbing or the like is used. An alignment film 5 was formed.

Plastic beads were scattered on either the upper substrate 1 or the lower substrate 2, the sealing material 11 was applied, and the upper and lower substrates 1 and 2 were pressure-sealed. At this time, the cell thickness was 5 μm. On the upper substrate 1, the phase difference plates 21A, 21
B and the polarizing plate 22A, and the retardation plate 2 on the lower substrate 2.
1C and the polarizing plate 22B were attached respectively.

In order to optimize the system in which the cell thickness is 5 μm at 240 ° twist, a nematic liquid crystal material added with a chiral agent is injected and sealed in the gap between the upper substrate 1 and the lower substrate 2 to obtain no coloring. A liquid crystal display device of Comparative Example 1 using the above light diffusion layer was prepared.

The color of the liquid crystal display device using the uncolored light diffusing layer produced as described above was evaluated.

First, when the color was measured during the reflective display, the chromaticity was (x, y) = (0.295, 0.329). Next, in order to measure the chromaticity at the time of transmissive display, measurement was performed using a backlight of (x, y) = (0.335, 0.345) as a light source. Was (x, y) = (0.284, 0.276). From this, it can be seen that there is a significant difference in chromaticity between the reflective display and the transmissive display, and the tint in the transmissive display is more blue than in the reflective display.

Example 1 The light diffusion layer was colored with Pigment Yellow # 83 in order to match the chromaticity in the reflective display and the transmissive display in the liquid crystal display device of Comparative Example 1. The chromaticity of the colored light diffusion layer 7A is (x, y) =
(0.312, 0.374), and the liquid crystal display device of Example 1 was prepared in the same manner as above.

When the chromaticity during the reflective display and the transmissive display were measured in the same manner as above, there was almost no change in the chromaticity during the reflective display (x, y) = (0.302, 0.338) Met. In addition, when visually observing the colors of the reflective display and the transmissive display, no significant difference in color was observed. Further, the chromaticity during the transmissive display is (x, y) = (0.2) after being subjected to color correction by the light diffusion layer 7A having the above chromaticity.
93, 0.329). Therefore, in the liquid crystal display device using the totally reflective metal thin film (reflection layer) 8A having the opening region 101, by coloring the light diffusion layer, the chromaticity at the time of reflective display is hardly impaired, and the transmission is performed. It can be seen that the chromaticity at the time of display can be corrected.

Regarding the chromaticity in the transmissive display, even if the chromaticity is the same, the image of the color visually recognized by the observer differs depending on the difference in luminance. In the present embodiment, the chromaticity at the time of the reflective display and the chromaticity at the time of the transmissive display are matched, but the chromaticity can be adjusted to an arbitrary chromaticity according to the luminance.

Comparative Example 2 As Comparative Example 2, Japanese Patent Laid-Open No.
The liquid crystal display device described in 1-110097 is prepared,
The chromaticity during transmissive display and reflective display was evaluated (see FIG. 3).

In this comparative example, a semi-transparent metal thin film (reflection layer) 8B is used in place of the total reflection metal thin film (reflection layer) 8A having the opening region 101, and liquid crystal display is performed in the same manner as above. Created the device. As in the case of Example 1 and Comparative Example 1, Ag-Pd was used as the semi-transparent metal thin film (reflection layer) 8B, and the metal thin film was made semi-transparent by thinning the film thickness. As the semi-transparent metal thin film (reflection layer) 8B, one having a film thickness of 350Å (35 nm), a reflectance of about 70%, and a transmittance of 20% was used. The configurations other than the metal thin film were the same as those of the liquid crystal display devices of Example 1 and Comparative Example 1. In this comparative example, the chromaticity was evaluated both in the case of using the uncolored light diffusion layer 7B and in the case of using the colored light diffusion layer 7A.

When the uncolored light diffusing layer 7B was used to measure the chromaticity during reflective display and during transmissive display,
The chromaticity during reflective display is (x, y) = (0.302, 0, 3
18), and the chromaticity at the time of transparent display is (x, y) = (0.
282, 0.256).

In order to match the chromaticity in the reflective display with the chromaticity in the transmissive display, it is colored with pigment yellow # 83, and the chromaticity is (x, y) = (0.324, 0.378). A liquid crystal display device was produced using the light diffusion layer 7A in the same manner as above. As a result, the chromaticity during reflective display is (x, y) =
It was (0.314, 0.342), and the chromaticity during transmissive display was (x, y) = (0.308, 0.312).
However, when visually observing the color at the time of the reflective display and the transmissive display, the color at the reflective display was clearly yellowish as compared with the color at the transmissive display. Therefore, Comparative Example 2
In the liquid crystal display device of, if the chromaticity during transmissive display is corrected,
The chromaticity during reflective display also changes. This is because the light observed on the display surface during reflective display is the reflected light on the metal thin film 8B,
The combined light with the reflected light at the interface between the light diffusion layer 7A and the substrate 2, and the reflected light at the interface between the light diffusion layer 7A and the substrate 2 is colored by passing through the colored light diffusion layer 7A. Because.

From the results of Example 1 and Comparative Examples 1 and 2 described above, the liquid crystal display device of the present invention can freely change the chromaticity during transmissive display while minimizing the change in chromaticity during reflective display. You can see that it can be adjusted.

(Embodiment 2) A liquid crystal display device according to a second embodiment of the present invention will be described. As the light diffusing layer 7A in this embodiment, a light diffusing layer having a refractive index larger than that of the coloring layer (color filter) 9 arranged in contact with the upper layer of the light diffusing layer 7A is used. A liquid crystal display device of this example was produced in the same manner as in. Specifically, the color filter 9 has a refractive index of 1.47, and the light diffusion layer 7A has a refractive index of 1.64.

First, as in Comparative Example 1, the refractive index is 1.6.
When the chromaticity at the time of transmissive display and reflective display was evaluated using the uncolored light diffusion layer 7B of 4, the chromaticity at transmissive display was (x, y) = (0.281, 0, 283), and the chromaticity during reflective display is (x, y) = (0.299,
It was 0.333).

Next, in order to match the chromaticity in the reflective display with the chromaticity in the transmissive display, the light diffusion layer is colored, and the chromaticity is (x, y) = (0.315, 0.379). ), And a liquid crystal display device was prepared using the light diffusion layer 7A made of a translucent resin having a refractive index of 1.64. As a result, the chromaticity during reflective display does not change (x, y) = (0.302,
It was 0.331). Also, the chromaticity during transparent display is
(X, y) = (0.304, 0.329). As shown in Example 1, in addition to coloring the light diffusing layer made of a translucent resin, in the present example, the refractive index of the light diffusing layer 7A is higher than that of the color filter 9 immediately above it. By increasing the chromaticity, only the chromaticity during transmissive display could be adjusted completely independently without affecting the chromaticity during reflective display at all.

Therefore, the light diffusion layer is colored so that the reflection layer in the reflection region is totally reflective, and the refractive index of the light diffusion layer is set to be higher than that of the film formed directly on the light diffusion layer. It is possible to further suppress the change in chromaticity and to freely adjust only the chromaticity during transmissive display.

In this embodiment, the film formed directly on the light diffusion layer 7A is the color filter 9, but the light diffusion layer 7A is used.
Even when a film other than the color filter, such as a protective layer or an insulating layer, is formed immediately above, the same effect as the present embodiment can be obtained by using the light diffusion layer 7A having a higher refractive index than this film. be able to.

Regarding the chromaticity in the transmissive display, even if the chromaticity is the same, the image of the color visually recognized by the observer differs depending on the difference in luminance. In the present embodiment, the chromaticity at the time of the reflective display and the chromaticity at the time of the transmissive display are matched, but the chromaticity can be adjusted to an arbitrary chromaticity according to the luminance.

(Third Embodiment) The requirements for transmissive display of a reflective / transmissive liquid crystal display device are roughly classified into three items: contrast, transmittance, and color reproducibility.

Without changing the display characteristics during reflective display,
In order to satisfy the above demands in the transmissive display, the simplest method is to optimize the axial angles of the retardation plate and the polarizing plate on the lower substrate (backlight side) side. However, when the respective axial angles of the retardation plate and the polarizing plate are optimized based on the above-mentioned demands, the polarization states differ from each other, so that the transmission display color is colored due to the retardation plate and the polarizing plate system. Therefore, in order to eliminate the coloring caused by the retardation plate and the polarizing plate system by coloring the light diffusion layer, the range of chromaticity when coloring the light diffusion layer was optimized.

First, as shown in FIG. 4, when the clockwise direction is positive and the counterclockwise direction is negative with respect to the alignment direction of the liquid crystal molecules, the axial angle of the first retardation plate 21A is -55 °. The first retardation plate 21A, the second retardation plate 21B and the polarizing plate 22A are sequentially attached to the upper substrate 1 so that the axial angle of the two retardation plates 21B is 80 ° and the axial angle of the polarizing plate 22A is 0 °. I attached it. The retardations of the liquid crystal layer 12 and the retardation plates 21A and 21B were set to 800 nm for the liquid crystal layer 12, 180 nm for the first retardation plate 21A, and 670 nm for the second retardation plate 21B.

Next, in the case where the contrast in the transmissive display is emphasized as much as possible, the retardation plate 21 attached to the lower substrate 2 is used.
The axis angles of C and the polarizing plate 22B are set as follows. Specifically, as shown in FIG. 6, when the axial angle of the polarizing plate 22B is −30 ° and the axial angle of the retardation plate 21C is 75 °, the contrast during transmissive display shows the maximum, and the contrast of 30 is displayed. was gotten. At this time, the chromaticity at the time of white display at the time of transmissive display was (0.27, 0.25). The retardation of the retardation plate 21C of the lower substrate 2 is 145 nm.
Met.

In the case of maximizing the improvement of the transmittance in the transmissive display without changing the respective axis angles of the retardation plate and the polarizing plate of the upper substrate 1, the retardation plate 21C and the polarization plate attached to the lower substrate 2 are polarized. Each axis angle of the plate 22B is set as follows.
Specifically, as shown in FIG. 7, the polarizing plate 22 of the lower substrate 2
The axis angle of B is 40 °, the axis angle of the retardation plate 21C is 90 °
At that time, the highest transmittance was exhibited. At this time, the chromaticity in the white display in the transmissive display is (0.33, 0.3
6). The retardation of the retardation plate 21C of the lower substrate 2 was 130 nm.

Similarly, when the axial angles of the retardation plate and the polarizing plate of the upper substrate 1 are not changed and the improvement of the color reproducibility at the time of transmissive display is emphasized as shown in FIG. , The polarizing plate 22B of the lower substrate 2 has an axial angle of 65 °, and the retardation plate 21C
When the axis angle of was −70 °, the color area was the largest and the color reproducibility during transmissive display was improved. At this time, the chromaticity at the time of white display at the time of transmissive display was (0.35, 0.33). The retardation of the retardation plate 21C of the lower substrate 2 was 140 nm. The above results are summarized in Table 1.

[0085]

[Table 1]

By the way, in the design of a general reflective / transmissive liquid crystal display device, the optimization of the respective axial angles of the polarizing plate and the retardation plate is a balance of the above three requirements (contrast, transmittance, color reproducibility). Is taken into consideration. Therefore,
The chromaticity at the time of white display in the transmissive display falls within a triangular area having the vertexes of the color coordinates at the time of white display in the transmissive display when specialized to each of the above three requests. Note that the color coordinates of the vertices of the triangle are values in the liquid crystal display device of the present embodiment, and when a coloring layer having a different chromaticity from that of the present embodiment is used, the chromaticity of the vertices of the triangle is The coordinates may differ from the values in this embodiment. However, R (red), G
When the (green) and B (blue) colored layers are used, the colors are approximately (0.35, 0.39), (0.29, 0.28) and (0.27, 0.31). A triangle whose vertex is the degree coordinate is formed.

Next, in the optimized reflective / transmissive liquid crystal display device, the chromaticity at the time of white display at the time of transmissive display is the chromaticity of the white point (WP) (0.31, 0.
Table 2 and FIG. 9 show the chromaticity of the light diffusing layer 7A for correction to 32).

[0088]

[Table 2]

That is, in the case of emphasizing contrast,
The chromaticity of the colored light diffusion layer 7A is (0.35, 0.3
9) and (0.29, 0.2
8) and (0.27,0.
31). Therefore, the contrast / transmittance / color reproducibility of the transflective liquid crystal display device during transmissive display is 3
In order to satisfy all the requirements, the axial angles of the polarizing plate 22B and the retardation plate 21C are optimized as shown in Table 1.
Furthermore, (0.35, 0.39), (0.29, 0.2
8), the light diffusion layer is colored with the chromaticity within the triangular region surrounded by the three color coordinates of (0.27, 0.31). As a result, it is possible to provide a reflective / transmissive liquid crystal display device capable of eliminating color tint at the time of transmissive display, excellent in contrast, transmittance, color reproducibility, and capable of excellent white display.

(Example 4) In the liquid crystal display device of Comparative Example 1, in order to correct the chromaticity at the time of transmissive display in accordance with the reflective display, as shown in FIG. 10, the light transmissive layer 7C was replaced by the light diffusing layer 7B. And a total reflection metal thin film 8A. As the light transmission layer 7C, the refractive index n = 2.4 and the film thickness 450Å
A (45 nm) TiO ₂ film was formed. In the same manner as above, when measuring the chromaticity during reflective display and transmissive display,
Chromaticity during reflective display is (x, y) = (0.300, 0.3
25), the chromaticity at the time of transparent display is (x, y) = (0.30
6, 0.310). From this, it is understood that the chromaticity in the transmissive display can be corrected with almost no loss in the chromaticity in the reflective display.

The change in chromaticity that occurs when the refractive index and the film thickness of the light transmitting layer 7C are changed will be described below. In Figure 11,
A simulation of chromaticity change during transmissive display when the film thickness is changed from 50 Å (5 nm) to 1000 Å (100 nm) when the refractive index n = 2.4 is shown. Figure 1
1, the film thickness is 350 Å (35 nm) to 550
By setting Å (55 nm), the light transmission layer 7C
In the case of not arranging (the point where the film thickness is 0Å in FIG. 11), the amount of change in chromaticity x, y is 0.01 or more. In other words, the chromaticity of the light incident on the light transmission layer 7C is (x
1, y1) and the chromaticity of the light emitted from the light transmitting layer 7C is (x2, y2), x2-x1 and y2-y1
Each of them is 0.01 or more, which is sufficiently recognizable. Thus, without coloring the light transmitting layer and the light diffusing layer,
By adjusting the refractive index and the film thickness of the light transmitting layer 7C,
The light transmitted through the light transmission layer 7C can have a yellowish tint. Therefore, as in the first embodiment, it is possible to suppress the change in chromaticity during reflective display and freely adjust only the chromaticity during transmissive display.

The film thickness in this embodiment is set when the transmitted light is colored blue due to the substrate or the alignment film, and for other colors, the film thickness is appropriately set. It is possible to perform color correction for both transmissive display and reflective display.

Comparative Example 3 FIG. 12 shows a simulation of chromaticity change when the light transmitting layer 7C of Example 4 is changed to a light transmitting layer having a refractive index n = less than 2.0. In particular,
The chromaticity change during transmissive display when the film thickness is changed from 50 Å (5 nm) to 1000 Å (100 nm) when the refractive index n = 1.8 is shown. As shown in FIG. 12, as in the case of Comparative Example 1, since the chromaticity during transmission is more bluish, it is possible to give a yellowish tint by setting it to a predetermined film thickness.

However, when the light transmitting layer is not provided (see FIG.
Chromaticity x, y with respect to film thickness 0 Å in 2)
The maximum change in is less than 0.01. In other words, when the refractive index n = 1.8, 50Å (5 nm) to 1000Å
At a film thickness in the range of (100 nm), sufficient recognizable yellow coloring cannot be obtained.

Example 5 FIG. 13 shows a simulation of chromaticity change when the light transmitting layer 7C of Example 4 is changed to the light transmitting layer 7C having a refractive index n = 2.0. In particular,
The chromaticity change at the time of transmissive display when the film thickness is changed from 50 Å (5 nm) to 1000 Å (100 nm) when the refractive index n = 2.0 is shown. As shown in FIG. 13, by setting the film thickness to about 600 Å (60 nm),
The amount of change in chromaticity x, y with respect to the case where the light transmission layer 7C is not arranged (the point of the film thickness 0Å in FIG. 13) is 0.01 or more. In other words, if the chromaticity of light incident on the light transmission layer 7C is (x1, y1) and the chromaticity of light emitted from the light transmission layer 7C is (x2, y2), then x2-x1 and y2-y1 Each is 0.01 or more, which is sufficiently recognizable. As described above, even if the light transmission layer and the light diffusion layer are not colored, the light transmitted through the light transmission layer 7C can be made yellowish by adjusting the refractive index and the film thickness of the light transmission layer 7C. it can. Therefore, as in the first embodiment, it is possible to suppress the change in chromaticity during reflective display and freely adjust only the chromaticity during transmissive display.

Example 6 FIG. 14 shows a simulation of chromaticity change when the light transmitting layer 7C of Example 4 is changed to the light transmitting layer 7C having a refractive index n = 3.0. In particular,
The chromaticity change at the time of transmissive display when the film thickness is changed from 50 Å (5 nm) to 1000 Å (100 nm) when the refractive index n = 3.0 is shown. As shown in FIG. 13, by setting the film thickness from 200 Å (20 nm) to 400 Å (40 nm), the chromaticity x, y for the case where the light transmission layer 7C is not arranged (the point of the film thickness 0 Å in FIG. 14) is set. Change of 0.01 or more. In other words, if the chromaticity of light incident on the light transmission layer 7C is (x1, y1) and the chromaticity of light emitted from the light transmission layer 7C is (x2, y2), then x2-x1 and y2-y1 Each is 0.01 or more, which is sufficiently recognizable. As described above, even if the light transmission layer and the light diffusion layer are not colored, the light transmitted through the light transmission layer 7C can be made yellowish by adjusting the refractive index and the film thickness of the light transmission layer 7C. it can. Therefore,
Similar to the first embodiment, it is possible to suppress a change in chromaticity during reflective display and freely adjust only chromaticity during transmissive display.

It should be noted that such a high refractive index (for example, n
(= 3.0 or more), it is known that the same effect can be obtained even when the film thickness is 1000Å (100 nm) or more, as can be seen from FIG. However, if the film thickness is set to 100 nm or more, it is not suitable for mass production because the cost is large and the film thickness is large so that the film thickness varies greatly.

From the above, the refractive index of the light transmission layer 7C is n = 2.0 or more, and the film thickness is 200Å (20 nm) or more.
By setting it to 0 Å (60 nm) or less, Example 1
Similarly, it can be seen that the change in chromaticity during reflective display can be suppressed and only the chromaticity during transmissive display can be freely adjusted.

(Embodiment 7) The liquid crystal display device of the present invention can be used as a display of various electronic devices. Today, products equipped with a display device include mobile phones, personal digital assistants (PDAs), personal computers (displays), notebook personal computers,
Examples include digital cameras, digital watches, watches, head-mounted displays, car navigations (monitors), projection TVs, and LCD TVs.

Among these electronic devices, the liquid crystal display device of the present invention is suitable for portable electronic devices which are used in various environments and in which low power consumption is essential. Hereinafter, a mobile phone including the liquid crystal display device of the present invention as a display unit will be described as an example of an electronic device. FIG. 15A is a front view and a rear view showing a state in which the foldable mobile phone is opened. The mobile phone (main body) 1000 has an antenna 100.
1, a voice output unit 1002, a main display unit 1003, operation switches 1005, a voice input unit 1006, and a sub-display unit 1004 on the back surface of the main body 1000. The liquid crystal display device of the present invention includes a main display unit 1003 and a sub display unit 1.
It can be applied to 004 etc.

The mobile phone is used in all environments, both outdoors and indoors. For example, when it is used outdoors at night, it is inevitable that external light cannot be used, so it is necessary to perform transmissive display using an illumination device built into a mobile phone. Further, when used in a bright place such as indoors, since it is possible to perform display by utilizing external light, reflective display can be performed. Therefore, it is desirable that the liquid crystal display device mounted in the mobile phone is a transmissive / reflective liquid crystal display device, which mainly has a low power consumption reflective display and can perform a transmissive display by a built-in lighting device as needed.

The liquid crystal display device of the present invention is used as a main display portion 1003.
Alternatively, by providing the sub-display unit 1004, a mobile phone which achieves reflective display with good chromaticity and can display good white color in transmissive display and which has excellent contrast, transmittance, and color reproducibility is provided. You can Further, by mounting the liquid crystal display device of the present invention on another portable electronic device, it is a mobile phone that has low power consumption and satisfies both a good color tone at the time of transmissive display and at the time of reflective display and has excellent visibility. An electronic device can be realized.

FIG. 15 shows a portable electronic device other than a mobile phone.
Examples are shown in (b) to (e). FIG. 15B is a perspective view of the PDA. The PDA (main body) 2000 has a display unit 20.
01, operation switch 2002, and external connection terminal 2003. The liquid crystal display device of the present invention can be applied to the display unit 2001.

FIG. 15C is a perspective view of the notebook computer. PC (main unit) 3000 has a display unit 300
1, a keyboard 3002, and an external connection terminal 3003. The liquid crystal display device of the present invention can be applied to the display portion 3001.

FIG. 15D is a perspective view of the liquid crystal television. The liquid crystal television (main body) 4000 includes a display unit 4001,
The receiver 4002 and the operation switch 4003 are included. The liquid crystal display device of the present invention can be applied to the display portion 4001.

FIG. 15 (e) is a perspective view of the video camera. The video camera (main body) 5000 has a display unit 500.
1, an image receiving portion 5002, operation switches 5003, and a finder 5004. The liquid crystal display device of the present invention can be applied to the display portion 5001.

As described above, the liquid crystal display device of the present invention has an extremely wide range of application and can be applied to electronic devices in all fields. In particular, since high-quality color display is possible in both reflection and transmission, the portable electronic device shown in FIG. 15 has high adaptability. In addition, it can also be used for electronic bulletin boards, FAX, and displays for home electronics terminals.

[0108]

As described above, according to the reflective / transmissive type display device substrate of the present invention, only the chromaticity during the transmissive display can be independently set without degrading the chromaticity during the reflective display. The chromaticity of can be set.

[Brief description of drawings]

FIG. 1 is a cross-sectional view schematically showing the structure of a liquid crystal display device according to a first embodiment.

2 is an enlarged cross-sectional view schematically showing one pixel in FIG.

FIG. 3 is an enlarged sectional view schematically showing one pixel of a conventional liquid crystal display device.

FIG. 4 is a diagram showing respective axial angles of retardation plates 21A and 21B and a polarizing plate 22A in Examples 1, 2 and 3 and Comparative Examples 1 and 2.

FIG. 5 is a diagram showing respective axial angles of a retardation plate 21C and a polarizing plate 22B in Examples 1 and 2 and Comparative Examples 1 and 2.

FIG. 6 is a diagram showing respective axial angles of the retardation plate 21C and the polarizing plate 22B when the contrast is emphasized in the third embodiment.

FIG. 7 is a diagram showing respective axial angles of the retardation plate 21C and the polarizing plate 22B when the transmittance is emphasized as much as possible in Example 3.

FIG. 8 is a diagram showing respective axial angles of the retardation plate 21C and the polarizing plate 22B when the color reproducibility is emphasized as much as possible in Example 3.

FIG. 9 is an xy chromaticity diagram for explaining correction of chromaticity of the light diffusion layer 7A in Example 3.

FIG. 10 is a cross-sectional view schematically showing the structure of the liquid crystal display device of the second embodiment.

FIG. 11 is a diagram showing a simulation of chromaticity change depending on the refractive index and the film thickness of the light transmission layer 7C in Example 4.

FIG. 12 is a diagram showing a simulation of chromaticity change depending on a refractive index and a film thickness of a light transmission layer 7C in Comparative Example 3.

FIG. 13 is a diagram showing a simulation of chromaticity change depending on the refractive index and the film thickness of the light transmission layer 7C in Example 5.

FIG. 14 is a diagram showing a simulation of chromaticity change depending on a refractive index and a film thickness of a light transmission layer 7C in Example 6.

FIG. 15 is a diagram illustrating an electronic device of the present invention.

[Explanation of symbols]

1, 2 transparent substrate 3, 4 transparent electrodes 5, 6 Alignment film 7A Colored light diffusion layer (light transmission layer) 7B Light diffusion layer not colored (light transmission layer) 7C Light transmission layer having a function of coloring light 8A Total reflection metal thin film (reflection layer) 8B Semi-transparent metal thin film (reflection layer) 9 Color filter (colored layer) 10 Protective layer (overcoat) 11 Seal material 12 Liquid crystal layer 21A First retardation plate on upper substrate 1 side 21B Second retardation plate on the upper substrate 1 side 21C Phase difference plate on the lower substrate 2 side 22A Polarizing plate on the upper substrate 1 side 22B Polarizing plate on the lower substrate 2 side 101 Open area of metal thin film 102 Reflection area of metal thin film

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hiroshi Yabuta             22-22 Nagaikecho, Abeno-ku, Osaka-shi, Osaka             Inside the company F-term (reference) 2H042 BA03 BA11 BA13 BA20 DA02                       DA12 DA22 DD00 DE00                 2H048 BA02 BB02 BB04 BB10 BB42                 2H091 FA02Y FA07X FA07Z FA11X                       FA12X FA12Z FA16Y FB02                       FC12 FD09 FD10 FD24 GA03                       GA06 HA10 KA02 KA03 KA10                       LA15 LA30 MA10

Claims (11)

[Claims] 1. A light transmitting layer for transmitting light is formed on a substrate, and a reflecting layer having a reflecting region for totally reflecting light and an opening region for transmitting light is formed on the light transmitting layer, and at least the above. A transmission / reflection dual-use display device substrate, wherein the light transmission layer in the opening region is colored. 2. The chromaticity of the colored light transmitting layer is XY.
Three chromaticity coordinates in the Z display system (0.35, 0.3
9), (0.29, 0.28) and (0.27, 0.
31) It is included in a triangular area surrounded by 31).
The substrate for a transflective display device according to [4]. 3. A light transmitting layer which transmits light is formed on the substrate, and a reflecting layer having a reflecting region for totally reflecting the light and an opening region for transmitting the light is formed on the light transmitting layer, and at least the above. The light-transmitting layer in the opening region has a function of coloring light transmitted through the light-transmitting layer. 4. The light transmission layer, when the chromaticity of light incident on the light transmission layer is (x1, y1) and the chromaticity of light emitted from the light transmission layer is (x2, y2), x2-x1
4. The transflective display device substrate according to claim 3, which has a function of setting each of y2 and y2 to 0.01 or more. 5. The transflective type display device substrate according to claim 3, wherein the light transmission layer in at least the opening region has a refractive index n of 2.0 or more. 6. The thickness of the light transmitting layer is 20 nm or more and 6
The transflective display device substrate according to claim 5, which has a thickness of 0 nm or less. 7. The transflective display according to claim 1, wherein a layer having a refractive index smaller than that of the light transmitting layer is formed on the light transmitting layer in the opening region. Substrate for equipment. 8. The transflective type display device substrate according to claim 1, wherein a colored layer is formed on the light transmissive layer and the reflective layer in the opening region. 9. The reflective layer has a fine concavo-convex structure.
The transmission / reflection dual-type display device substrate according to any one of claims 1 to 8. 10. A transflective dual-use display device substrate according to any one of claims 1 to 9, a counter substrate facing the transflective dual-use display device substrate, and a liquid crystal interposed between the both substrates. A transflective liquid crystal display device having a layer. 11. An electronic device comprising the transflective liquid crystal display device according to claim 10 as a display unit.