JP2001091958A - Liquid crystal display device and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To widen the viewing angle without deteriorating the picture quality of the liquid crystal display(LCD). SOLUTION: In the case voltage is applied between each of transparent electrodes 14, 15 of a liquid crystal panel 2, the rotary polarization of liquid crystal molecules in the liquid crystal layer 16 disappears and incident light on the liquid crystal panel 2 through a polarizing plate 3 passes through a polarizing plate 4. Since a number of transparent silicon particles 13 are dispersedly arranged on the liquid crystal layer 16 side surface of a transparent insulation substrate 12 with a nearly uniform density, without mutually overlapping and forming a single layer, the light radiated to the respective transparent silicon particles 13 is diffused with diffraction phenomena and the diffused light passes through the polarizing plate 4 from the transparent insulation substrate 12. Consequently, the viewing angle of the LCD 1 is widened so as to improve the visibility from the direction inclined with respect to the screen of the LCD 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display and a method for manufacturing the liquid crystal display.

[0002]

2. Description of the Related Art A transmission type liquid crystal display device (LCD: Liquid)
Crystal Display) has a transparent electrode (ITO (Indi
um Thin Oxide)), two transparent insulating substrates (glass substrates, etc.) are formed, two transparent insulating substrates are arranged so that each transparent electrode side faces each other, and liquid crystal is sealed in the gap between both substrates. Then, a liquid crystal panel is prepared, and polarizing plates are arranged on both sides (incident side and output side) of the liquid crystal panel. Then, a light source (backlight) is arranged to face the polarizing plate on the incident side, and light (illumination light) from the backlight passes through the polarizing plate on the incident side, so that only light of a predetermined polarization component is converted to liquid crystal. The light is incident on the panel. Here, when no voltage is applied between the transparent electrodes of the liquid crystal panel, optical rotation occurs in the liquid crystal molecules,
The light incident on the liquid crystal panel through the polarizing plate on the incident side is
During the transmission through the liquid crystal layer, the light is rotated by 90 ° due to the optical rotation of the liquid crystal molecules. When a voltage is applied between the transparent electrodes of the liquid crystal panel, the optical rotation of the liquid crystal molecules is lost, so that the light incident on the liquid crystal panel through the polarizer on the incident side is polarized by the polarizer on the output side. Through.

Further, a reflection type LCD uses a transparent insulating substrate having a transparent electrode formed on one side and a transparent insulating substrate having a reflective electrode (aluminum alloy or the like) formed on one side.
Two transparent insulating substrates are arranged so that the transparent electrode and the reflective electrode face each other, and liquid crystal is sealed in the gap between the two substrates to form a liquid crystal panel. The transparent insulating substrate on which the transparent electrodes of the liquid crystal panel are formed The structure is such that a polarizing plate is arranged on the side (incident side). Here, when no voltage is applied between the electrodes of the liquid crystal panel, optical rotation occurs in the liquid crystal molecules, and the light reflected by the reflective electrode after being incident on the liquid crystal panel through the polarizing plate is reflected by the liquid crystal layer. Since the liquid crystal molecules are rotated by 90 ° due to the optical rotation of the liquid crystal molecules while passing through, the liquid crystal molecules are blocked by the polarizing plate. When a voltage is applied between the electrodes of the liquid crystal panel, the optical rotation of the liquid crystal molecules disappears. Therefore, the light reflected by the reflective electrode after being incident on the liquid crystal panel through the polarizing plate is polarized. Transmit through the board.

As described above, the LCD displays a screen by transmitting and blocking light by utilizing the optical rotation of the liquid crystal.
There is a basic defect that an angle (viewing angle) that can be visually recognized by a user is narrow and visibility from an oblique direction with respect to the screen of the liquid crystal panel is poor.

[0005]

In order to increase the viewing angle of the LCD, Japanese Patent Laid-Open Publication No. Hei 8-3133891 (G0
2F 1/1335, G02B 5/02, G02B 6/00) and JP-A-8-33
A technique disclosed in, for example, Japanese Patent No. 4751 has been proposed.

Japanese Patent Application Laid-Open No. Hei 8-3133891 discloses a transmissive liquid crystal panel having a front surface on which a polarizing plate is disposed and a rear surface opposite thereto, a backlight disposed on the rear surface side,
There is disclosed an LCD including a light diffusing unit disposed on the front side and diffusing and emitting illumination light transmitted through the liquid crystal panel. Here, the light diffusion means is composed of two or more resin layers, and at least one resin layer is formed with a light diffusion layer in which transparent fine particles are spread in multiple layers.

Japanese Patent Application Laid-Open No. 8-3344751 discloses an LCD in which a backlight device is provided on one side of a liquid crystal cell and a viewing angle widening sheet is provided on the other side of the liquid crystal cell. I have. Here, the viewing angle widening sheet is configured by filling transparent light diffusing particles in a transparent matrix resin.

However, the techniques disclosed in these publications have the following problems. Since the light diffusing means or the viewing angle widening sheet is arranged on one side of the liquid crystal panel (liquid crystal cell), the distance between the liquid crystal and the light diffusing means or the viewing angle widening sheet increases.
Therefore, only a screen with reduced contrast (a so-called "blurred" screen) can be obtained.

[0009] The light diffusion layer of the light diffusion means has fine particles spread in multiple layers. Light diffusing particles are filled in the viewing angle widening sheet. Therefore, almost all light transmitted through the liquid crystal panel (liquid crystal cell) is transmitted through the particles, and almost no light is transmitted through the particles.
Liquid crystal panel (liquid crystal cell), although excellent in light diffusion
, The amount of light transmitted vertically is greatly reduced. Therefore, only a dark screen can be obtained.

As described above, the viewing angle is increased, but the image quality is greatly reduced. The present invention has been made to solve the above problems, and the object is to
An object of the present invention is to increase the viewing angle without lowering the image quality of the LCD.

[0011]

Means for Solving the Problems and Effects of the Invention The invention according to the first aspect of the present invention, which has been made to achieve the above object, comprises a first or a second transparent insulating substrate arranged to face each other via a liquid crystal layer. A gist of the invention is a transmission type liquid crystal display device in which a large number of transparent particles are dispersed and arranged on one or both surfaces of the liquid crystal layer side and a transparent electrode is formed so as to cover the transparent particles.

Therefore, according to the present invention, the light applied to the transparent particles is diffused by the diffraction phenomenon, and the diffused light passes through the transparent insulating substrate. Visibility in an oblique direction with respect to the screen of the display device can be improved. The liquid crystal layer is in contact with the transparent particles via the thin transparent electrode, and the distance between the liquid crystal layer and the transparent particles is small, so that a screen with improved contrast (a so-called “clear” screen) can be obtained. As a result, the viewing angle can be increased without lowering the image quality of the liquid crystal display device.

Next, a second aspect of the present invention is the first aspect.
In the liquid crystal display device described in the above, the plurality of transparent particles are dispersedly arranged in one layer without overlapping with each other at a substantially uniform density with respect to the surface of the first or second transparent insulating substrate, The gist is that there is a portion exposed from the transparent particles on the surface of the first or second transparent insulating substrate.

Therefore, according to the present invention, since there is a portion exposed from the transparent particles on the surface of the transparent insulating substrate, of the light incident on the liquid crystal panel, the light incident on the exposed portion is scattered. Without being transmitted through the transparent insulating substrate. Therefore, it is possible to sufficiently secure the amount of light transmitted in the vertical direction to the liquid crystal panel, and a bright screen can be obtained. As a result, the image quality of the liquid crystal display device can be further improved in addition to the operation and effect of the invention described in claim 1.

Next, according to a third aspect of the present invention, a transparent insulating substrate having a transparent electrode formed on one side and an insulating substrate having a reflective electrode formed on one side face the transparent electrode and the reflective electrode. A liquid crystal panel having a liquid layer filled with liquid crystal in a gap between the transparent insulating substrate and the insulating substrate, and a plurality of particles arranged and dispersed on the surface of the insulating substrate on the liquid crystal layer side. The gist is a reflective liquid crystal display device in which a reflective electrode is formed so as to cover particles.

Therefore, according to the present invention, since the reflection electrode is formed so as to cover the particles, irregularities are formed on the surface of the reflection electrode along the shape of the particles. Therefore, the light reflected by the reflective electrode is diffused by unevenness on the surface of the reflective electrode, and the diffused light passes through the transparent insulating substrate. Therefore, the viewing angle of the liquid crystal display device is expanded by the diffusion of light by the reflective electrode, and the visibility of the screen of the liquid crystal display device from an oblique direction can be improved. As a result, the viewing angle can be increased without lowering the image quality of the liquid crystal display device.

In the liquid crystal display device according to any one of the first to third aspects, the transparent particles or the particles may be transparent silicon particles. According to a fifth aspect of the present invention, in the method for manufacturing a liquid crystal display device according to the fourth aspect, a step of forming an amorphous silicon film on the transparent insulating substrate or the insulating substrate and a heat treatment are performed. The amorphous silicon film is heated and melted, the heated and melted amorphous silicon film is changed into a number of molten droplets by surface tension, and then the molten droplet is cooled and recrystallized, and The method may include a step of forming a large number of transparent silicon particles, and a step of forming the transparent electrode or the reflective electrode covering the transparent silicon particles on the transparent insulating substrate or the insulating substrate.

In this case, the transparent silicon particles can be easily and easily produced. In the embodiments of the invention described below, “transparent particles” or “particles” described in claims or means for solving the problems correspond to transparent silicon particles 13.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic sectional view of the LCD 1 of the first embodiment. The transmissive LCD 1 includes a liquid crystal panel 2, polarizing plates 3 and 4, and a backlight 5.

The liquid crystal panel 2 includes a transparent insulating substrate (for example,
Glass substrates, quartz substrates, etc. 11, 12, transparent silicon particles 13, transparent electrodes (for example, ITO, etc.) 14, 1
5. It is composed of a liquid crystal layer 16. Transparent insulating substrate 11
The transparent electrode 14 is formed on one side (the liquid crystal layer 16 side).

One side of the transparent insulating substrate 12 (the liquid crystal layer 16 side)
, A large number of transparent silicon particles 13 are dispersedly arranged in one layer at a substantially uniform density without overlapping each other.
A transparent electrode 15 is formed on the surface of the transparent insulating substrate 12 exposed from each transparent silicon particle 13 so as to cover each transparent silicon particle 13.

The transparent insulating substrates 11 and 12 are arranged so that the respective transparent electrodes 14 and 15 face each other, and a liquid crystal is sealed in a gap between the transparent electrodes 14 and 15 to form a liquid crystal layer 16. Transparent insulating substrate 1 in liquid crystal panel 2
The polarizing plate 3 is arranged on one side (incident side), and the polarizing plate 4 is arranged on the transparent insulating substrate 12 side (outgoing side). Further, a backlight 5 which is a light source for irradiating substantially parallel light is disposed opposite to the polarizing plate 3.

In the LCD 1 configured as described above,
Light (illumination light) from the backlight 5 passes through the polarizing plate 3 on the incident side, and only light having a predetermined polarization component is incident on the liquid crystal panel 2. Here, each of the transparent electrodes 14 of the liquid crystal panel 2,
When no voltage is applied between the liquid crystal layers 16,
Optical rotation occurs in the liquid crystal molecules therein, and light incident on the liquid crystal panel 2 through the polarizing plate 3 is rotated by 90 ° due to the optical rotation of the liquid crystal molecules while passing through the liquid crystal layer 16. Is shut off by

The transparent electrodes 14 of the liquid crystal panel 2
When a voltage is applied between the liquid crystal layers 15, the optical rotation of the liquid crystal molecules in the liquid crystal layer 16 disappears, so that light incident on the liquid crystal panel 2 through the polarizing plate 3 passes through the polarizing plate 4.
At this time, since a large number of transparent silicon particles 13 are dispersed and arranged on the surface of the transparent insulating substrate 12 on the side of the liquid crystal layer 16 at a substantially uniform density without overlapping each other, each transparent silicon particle 13 is irradiated. The diffused light is diffused by a diffraction phenomenon, and the diffused light passes through the polarizing plate 4 from the transparent insulating substrate 12. Therefore, the viewing angle of the LCD 1 is expanded by the diffusion of light by the transparent silicon particles 13, and L
Visibility from an oblique direction with respect to the screen of the CD 1 can be improved.

The liquid crystal layer 16 is in contact with each transparent silicon particle 13 via the thin transparent electrode 15, and the distance between the liquid crystal layer 16 and each transparent silicon particle 13 is small. "Screen) can be obtained. Further, since there is a portion 12a exposed from each transparent silicon particle 13 on the surface of the transparent insulating substrate 12, of the light incident on the liquid crystal panel 2 through the polarizing plate 3, the light incident on the portion 12a is not shown in the figure. As shown by the arrow A, the light passes through the polarizing plate 4 from the transparent insulating substrate 12 without being scattered. Therefore, it is possible to sufficiently secure the amount of light transmitted in the vertical direction (the direction of arrow A) with respect to the liquid crystal panel 2, and it is possible to obtain a bright screen.

As described in detail above, L of the first embodiment is
According to CD1, the viewing angle can be increased without deteriorating the image quality. Next, a method of forming the transparent silicon particles 13 will be described with reference to FIG. First, an amorphous silicon film 17 is deposited on the transparent insulating substrate 12 by a predetermined thickness (see FIG. 2A). In addition, what method (for example, L
PCVD (Low Pressure Chemical Vapor Deposition)
Method, PECVD (Plasma Enhanced Chemical Vapor Dep.
osition) method, PVD (Physical Vapor Deposition) method, or the like.

Next, when the amorphous silicon film 17 is heated and melted by performing a heat treatment, the amorphous silicon film 17 changes into a large number of molten droplets due to surface tension. Then, when the molten droplet of the amorphous silicon is cooled and recrystallized, many transparent silicon particles 13 are formed from the molten droplet (see FIG. 2B).

Note that any method (for example,
Laser annealing method for irradiating various lasers (KrF excimer laser, ArF excimer laser, F ₂ excimer laser, ruby laser, YAG laser, carbon dioxide laser, etc.), electron beam annealing method, various lamps (ultra high pressure mercury lamp, halogen lamp, xenon) An RTA (Rapidly Thermal Anneal) method for irradiating light from a shot arc lamp, a tungsten lamp, an infrared light lamp, or the like, a furnace annealing method (resistance heating, high-frequency heating, a lamp heating furnace, or the like) may be used. However, in order to heat and melt the amorphous silicon film 17 efficiently, an EL using an excimer laser well absorbed by the amorphous silicon is used.
The A (Excimer Laser Anneal) method is most useful.

Subsequently, the transparent insulating substrate 1 is formed using the PVD method.
A transparent electrode 15 that covers the transparent silicon particles 13 is deposited on the substrate 2 (see FIG. 2C). As described above, the transparent silicon particles 13 can be easily and easily formed. still,
If a method that does not unnecessarily heat the transparent insulating substrate 12 (for example, a laser annealing method or an RTA method) is used as the heat treatment method, it is not necessary to use an expensive material having high heat resistance for the transparent insulating substrate 12. Since an inexpensive material having low heat resistance can be used, the manufacturing cost of the LCD 1 can be reduced.

When the laser annealing method or the RTA method is used as the heat treatment, if the amount of impurities (oxygen, nitrogen, carbon, etc.) that absorbs laser light or lamp light in the amorphous silicon film 17 increases, the laser light or The lamp light is easily absorbed by the amorphous silicon film 17, and the heating and melting are facilitated. Therefore, on condition that the transparency of the transparent silicon particles 13 is not reduced, the type and amount of impurities in the amorphous silicon film 17 may be appropriately set to promote the heating and melting.
In this case, since the material for forming amorphous silicon containing impurities is less expensive than the material for forming amorphous silicon having a low impurity content and high purity, LC
The manufacturing cost of D1 can be reduced.

FIG. 3 is a characteristic diagram showing conditions for forming the transparent silicon particles 13 (the number of laser shots with respect to the irradiation energy density of laser light) when the ELA method using a KrF excimer laser is used for the heat treatment. When the thickness of the amorphous silicon film 17 is different (70 nm
Or 30 nm), the conditions for forming the transparent silicon particles 13 (shaded portions in the figure) are slightly different, and when the thickness is large (
In the case where the thickness is smaller than (nm), the transparent silicon particles 13 are formed even when the irradiation energy density is reduced and the number of laser shots is reduced.

FIG. 4 shows the transparent silicon particles 13 shown in FIG.
FIG. 4 is a characteristic diagram showing a particle size distribution of transparent silicon particles 13 under the formation conditions of FIG. Regardless of the thickness of the amorphous silicon film 17, the diameter of the transparent silicon particles 13 is about 300 n.
It is almost constant in the range from m to about 600 nm, and it can be seen that there is hardly anything outside this range. This is because the particle size of the transparent silicon particles 13 is determined by the wettability between the heated and melted amorphous silicon and the transparent insulating substrate 12, the time from the melting of the amorphous silicon film 17 to the recrystallization, and the like. It is thought to be.

FIG. 5 shows the transparent silicon particles 13 shown in FIG.
FIG. 4 is a characteristic diagram showing the occupation density of the transparent silicon particles 13 under the formation conditions of FIG. Note that the occupation density of the transparent silicon particles 13 is set to “1” when the unit area of the surface of the transparent insulating substrate 12 is entirely covered with the transparent silicon particles 13.

It can be seen that the occupation density of the transparent silicon particles 13 falls within a range of about 0.3 to 0.4. When the thickness of the amorphous silicon film 17 is different (70 nm or 30 nm), the occupation density of the transparent silicon particles 13 is slightly different, and when the film thickness is thinner (30 nm) than when the film thickness is thicker (70 nm), the irradiation is lower. It can be seen that the occupation density of the transparent silicon particles 13 formed at the energy density decreases.

FIG. 6 is a characteristic diagram showing the contrast ratio with respect to the viewing angle of the LCD. According to the conditions for forming the transparent silicon particles 13 shown in FIG. 3 (“O” and “X” in the figure), the amorphous silicon film 17 has almost no relation to the film thickness.
It can be seen that a substantially uniform contrast ratio can be obtained at a wide viewing angle.

In addition, outside the conditions for forming the transparent silicon particles 13 shown in FIG.
Are almost not formed, so that the viewing angle is narrow as in the case of the conventional LCD (“●” in the figure) in which the amorphous silicon film 17 is not used.

From these characteristic diagrams, if the transparent silicon particles 13 are formed under the conditions for forming the transparent silicon particles 13 shown in FIG. 3, the particle size (see FIG. 4) and the occupation density (see FIG. 5) of the transparent silicon particles 13 It can be seen that the viewing angle of the LCD 1 can be increased irrespective of the difference between the two and the thickness of the amorphous silicon film 17.

Here, as described above, since the transparent silicon particles 13 are formed by the surface tension of the amorphous silicon film 17 melted by heating, the transparent silicon particles 1 are formed.
The shape of 3 is a shape composed of continuous curved surfaces such as a sphere, a spheroid, an egg, and a hemisphere. Therefore, light diffusion by the transparent silicon particles 13 is performed smoothly. Incidentally, when the shape of the transparent silicon particles 13 is a polyhedral shape composed of a plurality of planes, the light is not diffused smoothly due to the generation of total reflection light, which is not desirable.

The thickness range of the amorphous silicon film 17 is suitably from 10 nm to 100 nm, preferably from 30 nm to 70 nm, particularly preferably from 40 nm to 6 nm.
0 nm. If the thickness of the amorphous silicon film 17 is larger than this range, it tends to be difficult to reliably heat and melt the amorphous silicon film 17 with the above-described heat treatment method at present. On the other hand, if the thickness of the amorphous silicon film 17 is smaller than this range, the amorphous silicon melted by heating is scattered, so that the transparent silicon particles 13 tend not to be formed.

Further, the range of the particle size of the transparent silicon particles 13 is preferably 100 nm to 500 nm, and more preferably 2 nm to 500 nm.
00 nm to 400 nm, particularly preferably 300 nm to 3
50 nm. If the particle size of the transparent silicon particles 13 is larger than this range, the amount of light transmitted in the direction perpendicular to the liquid crystal panel 2 decreases, and the screen tends to be dark and the display quality tends to deteriorate. In addition, the transparent silicon particles 13
If the particle size of the transparent silicon particles 13 is smaller than this range, the amount of light diffracted by each transparent silicon particle 13 decreases, and the viewing angle expanding effect tends to be impaired.

The occupation density of the transparent silicon particles 13 ranges from 0.1 to 0, assuming that the occupation density = “1” when the entire unit area of the surface of the transparent insulating substrate 12 is covered with the transparent silicon particles 13. .5 is suitable, preferably 0.2
-0.4, particularly preferably 0.3-0.4. If the occupation density of the transparent silicon particles 13 is larger than this range, the amount of light transmitted in a direction perpendicular to the liquid crystal panel 2 decreases, and the screen tends to be dark. If the occupation density of the transparent silicon particles 13 is smaller than this range, LC
There is a tendency that the viewing angle enlarging effect of D1 cannot be sufficiently obtained.

The present invention is not limited to the above-described first embodiment, but may be embodied as follows. Even in such a case, the same operation or effect as or more than that of the first embodiment can be obtained. Obtainable. (1) FIG. 7A is a schematic sectional view of the LCD 21 of the second embodiment.

The LCD 21 differs from the LCD 1 of the first embodiment shown in FIG. 1 in that many transparent silicon particles 13 are arranged on the transparent insulating substrate 11 side, not on the transparent insulating substrate 12 side. . That is, on one surface (the liquid crystal layer 16 side) of the transparent insulating substrate 11, a large number of transparent silicon particles 13 are dispersedly arranged in one layer at a substantially uniform density without overlapping each other. On the surface of the transparent insulating substrate 11 exposed from each transparent silicon particle 13, a transparent electrode 14 is formed so as to cover each transparent silicon particle 13. On the other hand, one surface of the transparent insulating substrate 12 (the liquid crystal layer 16
Side), no transparent silicon particles 13 are arranged,
Only the transparent electrode 15 is formed.

FIG. 7B shows an LCD 31 according to the third embodiment.
FIG. The LCD 31 differs from the LCD 1 of the first embodiment shown in FIG. 1 in that many transparent silicon particles 13 are arranged not only on the transparent insulating substrate 12 side but also on the transparent insulating substrate 11 side. That is,
The LCD 31 has a structure combining the first embodiment and the second embodiment.

As shown in the first to third embodiments, the transparent silicon particles 13 need only be disposed on at least one of the transparent insulating substrates 11 and 12, and in any case, the transparent silicon particles 13 are different from those of the first embodiment. Similar functions and effects can be obtained. (2) FIG. 8 is a schematic sectional view of the LCD 41 of the fourth embodiment.

The reflective LCD 41 is different from the transmissive LCD 1 of the first embodiment shown in FIG. 1 in that the polarizing plate 3 and the backlight 5 are omitted and the transparent electrode 14 is a reflective electrode (such as an aluminum alloy). 42
The point is that a number of transparent silicon particles 13 are arranged on the transparent insulating substrate 11 side.

That is, the reflection type LCD 41 is composed of the liquid crystal panel 2 and the polarizing plate 4. LCD panel 2
Are transparent insulating substrates 11 and 12, transparent silicon particles 13,
It comprises a transparent electrode 14, a reflective electrode 42, and a liquid crystal layer 16.

One side of the transparent insulating substrate 11 (the liquid crystal layer 16 side)
, A large number of transparent silicon particles 13 are dispersedly arranged in one layer at a substantially uniform density without overlapping each other.
A reflective electrode 42 is formed on the surface of the transparent insulating substrate 11 exposed from each transparent silicon particle 13 so as to cover each transparent silicon particle 13. The reflection electrode 42
The PVD method may be used for the formation.

One side of the transparent insulating substrate 12 (the liquid crystal layer 16 side)
No transparent silicon particles 13 are arranged, and only a transparent electrode 15 is formed. The polarizing plate 4 is disposed on the liquid crystal panel 2 on the side of the transparent insulating substrate 12 (incident side).

In the LCD 41 configured as described above, when no voltage is applied between the electrodes 14 and 42 of the liquid crystal panel 2, optical rotation occurs in the liquid crystal molecules in the liquid crystal layer 16 and passes through the polarizing plate 4. The light reflected by the reflection electrode 42 after being incident on the liquid crystal panel 2 is rotated by 90 ° due to the optical rotation of the liquid crystal molecules while passing through the liquid crystal layer 16, and is thus blocked by the polarizing plate 4.

Then, the respective electrodes 14 and 42 of the liquid crystal panel 2
When a voltage is applied therebetween, the optical rotation of the liquid crystal molecules in the liquid crystal layer 16 disappears, so that the light reflected by the reflective electrode 42 after being incident on the liquid crystal panel 2 through the polarizing plate 4 is: The light passes through the polarizing plate 4. At this time, the transparent insulating substrate 1
2 has a large number of transparent silicon particles 13 on the surface on the liquid crystal layer 16 side.
Are distributed in one layer without overlapping with each other at a substantially uniform density, and the reflective electrode 42 is formed so as to cover each transparent silicon particle 13. Irregularities along the shape are formed. Therefore, the light reflected by the reflective electrode 42 is diffused by unevenness on the surface of the reflective electrode 42, and the diffused light passes through the polarizing plate 4 from the transparent insulating substrate 12. Therefore, the diffusion of light by the reflective electrode 42 causes
The viewing angle of D41 is enlarged, and the visibility of the LCD 41 from oblique directions can be improved.

As described above, the LCD 41 of the fourth embodiment is
According to this, the viewing angle can be increased without lowering the image quality. In the LCD 41, since the transparent silicon particles 13 are covered with the reflective electrode 42, the transparent silicon particles 13 do not need to be transparent. Further, the transparent silicon particles 13 may be replaced with other appropriate particles (for example, plastic beads, glass beads, ceramic beads, various metal particles, and the like), and the particles need not be transparent. And
The transparent insulating substrate 11 does not need to be transparent.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a first embodiment embodying the present invention.

FIG. 2 is a schematic cross-sectional view for explaining a method for producing transparent silicon particles of each embodiment.

FIG. 3 is a characteristic diagram for explaining the operation of the first embodiment.

FIG. 4 is a characteristic diagram for explaining the operation of the first embodiment.

FIG. 5 is a characteristic diagram for explaining the operation of the first embodiment.

FIG. 6 is a characteristic diagram for explaining the operation of the first embodiment.

FIG. 7A is a schematic cross-sectional view of a second embodiment embodying the present invention. FIG. 7B is a schematic sectional view of a third embodiment embodying the present invention.

FIG. 8 is a schematic sectional view of a fourth embodiment embodying the present invention.

[Explanation of symbols]

 1, 21, 31, 41: Liquid crystal display (LCD) 2: Liquid crystal panel 3, 4: Polarizer 5: Backlight 11, 12: Transparent insulating substrate 13: Transparent silicon particles 14, 15, Transparent electrode 16: Liquid crystal layer 17: amorphous silicon film 42: reflective electrode

Claims (5)

[Claims] 1. A method in which a large number of transparent particles are dispersed and arranged on one or both surfaces of a liquid crystal layer of a first or second transparent insulating substrate opposed to each other with a liquid crystal layer interposed therebetween. A transmissive liquid crystal display device comprising a transparent electrode formed so as to cover the liquid crystal display device. 2. The liquid crystal display device according to claim 1, wherein the plurality of transparent particles have a substantially uniform density with respect to a surface of the first or second transparent insulating substrate without overlapping each other. Dispersed in layers, the first or second
A liquid crystal display device characterized in that the surface of the transparent insulating substrate of (1) has a portion exposed from the transparent particles. 3. A transparent insulating substrate having a transparent electrode formed on one surface and an insulating substrate having a reflective electrode formed on one surface, wherein the transparent electrode and the reflective electrode are arranged to face each other. A liquid crystal panel having a liquid layer in which liquid crystal is sealed in a gap between the liquid crystal layer and a plurality of particles dispersedly arranged on the surface of the insulating substrate on the liquid crystal layer side, and a reflective electrode is formed so as to cover the particles. A reflective liquid crystal display device. 4. The reflection type liquid crystal display device according to claim 1, wherein the transparent particles or the particles are transparent silicon particles. 5. The method for manufacturing a liquid crystal display device according to claim 4, wherein: a step of forming an amorphous silicon film on the transparent insulating substrate or the insulating substrate; and performing heat treatment to heat and melt the amorphous silicon film. Then, the heated and melted amorphous silicon film is changed into a large number of molten droplets by surface tension, and then the molten droplet is cooled and recrystallized, and a large number of transparent silicon particles are formed from the molten droplet. A method for manufacturing a liquid crystal display device, comprising: a forming step; and a step of forming the transparent electrode or the reflective electrode that covers transparent silicon particles on the transparent insulating substrate or the insulating substrate.