JP2000029021A - Reflective liquid crystal display - Google Patents

Abstract

(57) [Problem] A bright reflective liquid crystal having no parallax, excellent viewing angle characteristics, and a combination of a new liquid crystal display mode capable of controlling an absorption state and a scattering state by applying a voltage and an anisotropic uneven reflector. A display device is provided. SOLUTION: A polarizer on the light incident side of a liquid crystal element, an insulating substrate having a transparent electrode formed thereon, a light reflecting member having a light reflecting surface formed thereon, and a liquid crystal molecule and a liquid crystal polymer are both twisted. In a reflective liquid crystal display device, the light becomes circularly polarized light on the reflection surface for dark display, becomes linearly polarized light on the emission surface after reflection, and becomes scattered light on the emission surface after reflection for bright display. The reflective member has a concave-convex shape, and the concave-convex shape has an average concave-convex period that differs depending on the orientation in the substrate plane, and the concave-convex reflective film has no or long irregularities, and the thickness of the liquid crystal layer twisted between the upper and lower substrates. The liquid crystal molecules are substantially perpendicular to the major axis direction of the liquid crystal molecules at a position substantially half of the direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a direct-view reflective liquid crystal display device without a backlight, and more particularly to office automation equipment such as a word processor or a so-called notebook personal computer, various video equipment and game equipment. The present invention relates to a reflection-type liquid crystal display device suitably used for a liquid crystal display.

[0002]

2. Description of the Related Art Conventionally, a reflection type liquid crystal display device has
An N (twisted nematic) system and an STN (super twisted nematic) system are used. In order to apply these TN or STN liquid crystal display elements as a reflection type liquid crystal display device, in view of the principle of the display method, a configuration is adopted in which the liquid crystal display element is sandwiched between a pair of polarizing plates, and a reflection plate is provided outside the pair. Need to be installed.
Then, due to the thickness of the glass substrate used for the liquid crystal display device, the angle at which the user looks at the reflective liquid crystal display device, that is, the normal direction of the glass substrate and the direction at which the user looks at the liquid crystal display device. There is a problem that parallax is generated depending on the angle made and the display is recognized twice.

[0003] Regarding colorization, conventionally, for example, three dots (red, green,
A blue color micro-filter is provided, and multi-color display or full-color display is performed by additive mixing. However, in the liquid crystal display mode, since two polarizing plates are used, the display is very dark, and addition color mixing is not satisfactorily performed due to the generation of the parallax. Therefore, good display cannot be obtained in the reflective color display.

Based on these backgrounds, in recent years, liquid crystal display elements in which one polarizing plate and one reflecting plate are combined have been developed. As one example, a direct-view reflective liquid crystal display device in which a twisted liquid crystal layer is disposed between a reflective plate (arranged on the inner surface of the cell) and a polarizing plate on which fine irregularities are formed is disclosed in Japanese Patent Laid-Open Publication No. Heisei 3 (1999).
No. 223715.

On the other hand, a reflection type liquid crystal display device comprising a polarizing plate, a quarter wavelength plate, a polymer dispersed liquid crystal, and a specular reflection plate in this order from the light incident side is disclosed in Japanese Patent Application Laid-Open No. 7-280.
No. 54 discloses this. This reflection type liquid crystal display device has a light-transmitting electrode formed on one surface of a light-transmitting substrate,
With the reflective electrode formed on one side of the substrate, the polymer-dispersed liquid crystal layer is sandwiched, and on the other side of the translucent substrate,
A quarter-wave plate and a polarizer are sequentially arranged in a laminated state. The liquid crystal of the polymer-dispersed liquid crystal layer is randomly oriented when no voltage is applied, and the light transmitted therethrough is depolarized, and the display state becomes a bright state.

On the other hand, when a voltage is applied, the liquid crystal is oriented perpendicular to the translucent electrode and the reflective electrode, so that the birefringence effect does not occur with respect to the vertically incident light. The light emitted to the outside again is 1 /
Since the light passes through the four-wavelength plate twice, a phase change corresponding to substantially a half wavelength is generated. As a result, the polarization plane is rotated by 90 degrees. It is.

[0007]

SUMMARY OF THE INVENTION The above-mentioned Japanese Patent Application Laid-Open No. 3-223 is disclosed.
In the reflection type liquid crystal display device described in Japanese Patent No. 715, the transmission state and the absorption state are controlled by a voltage, and therefore, in order to display white, a scattering reflection film cannot be omitted on the back surface of the liquid crystal layer. That is, the performance of the scattering reflector determines the display quality.
For example, if the reflector used for the above display principle does not maintain the polarization of incident light, conversion from clockwise circularly polarized light to leftward circularly polarized light, or vice versa, will not be performed efficiently, At the time of dark display, light leaks and causes a decrease in contrast.

[0008] As a reflection member for maintaining the polarization, there is a flat mirror reflection member. In this case, the surrounding information is reflected on the display in a bright state. Therefore, there is a problem that the visibility is remarkably reduced. Therefore, it is desirable that the reflector has a light diffusing property. However, in such a diffuse reflection plate, when the degree of polarization retention is increased, the contrast is increased, but the viewing angle is narrowed.

On the other hand, there is a disadvantage that the contrast is extremely lowered when the degree of polarization retention is reduced, the scattering property is increased, and the viewing angle is widened. As described above, it was not possible to obtain a reflection plate having both characteristics of maintaining perfect polarization and diffusivity, and it was not possible to realize a high-contrast, easy-to-view display.

In the reflection type liquid crystal display device disclosed in JP-A-7-28054, a dark state without scattering is realized.
However, at the time of the bright state, the polarizing plate 1/1 of the incident light.
2 is absorbed, a random depolarized state is obtained in the polymer dispersion layer, and a half of the light is absorbed by the polarizing plate at the time of emission, so that the brightness eventually becomes 1/4 or less, resulting in darkness. was there.

An object of the present invention is to solve the above-mentioned technical problems and to combine a new liquid crystal display mode capable of controlling an absorption state and a scattering state by applying a voltage and an anisotropic uneven reflection plate, so that there is no parallax and no visual field. An object of the present invention is to provide a bright reflective liquid crystal display device having excellent angular characteristics.

[0012]

According to a first aspect of the present invention, there is provided a reflective liquid crystal display device comprising at least one polarizer and at least a transparent electrode on a light incident side of a liquid crystal element. An insulating substrate, a light reflecting member having a light reflecting surface formed thereon, and a liquid crystal layer encapsulated between the insulating substrate and the reflecting member, in which liquid crystal molecules and liquid crystal polymer are both twisted and aligned. In the dark display, the linearly polarized incident light enters, the reflecting surface becomes circularly polarized light, the reflected light becomes the linearly polarized light with the 90 ° polarization plane rotated on the emitting surface after reflection, and the linearly polarized incident light in the bright display. In the reflection type liquid crystal display device, in which light enters, and after reflection, becomes a scattered light that has passed through only the polarization component in the same direction as the incident light on the emission surface, the light reflecting member has an uneven shape, and the uneven shape is in the plane of the substrate. The average unevenness period differs depending on the direction It is required that the azimuth of the uneven reflection film not having or having a long unevenness and the major axis azimuth of the liquid crystal molecules at a position substantially half the thickness direction of the liquid crystal layer twisted between the upper and lower substrates are substantially perpendicular to each other. Features.

Further, the reflection type liquid crystal display device according to the present invention is characterized in that the twist angle of the liquid crystal layer in which both the liquid crystal molecules and the liquid crystalline polymer are twisted is within 100 degrees.

According to a third aspect of the present invention, in the reflective liquid crystal display device, in the liquid crystal display device, an angle between a transmission axis of the polarizing plate and an alignment direction of the liquid crystal molecules on the incident side is substantially parallel. It is characterized by.

According to a fourth aspect of the present invention, there is provided the reflective liquid crystal display device, wherein the direction of the transmission axis of the polarizing plate and the upper and lower substrates are:
The liquid crystal molecules have a thickness of about 1 in the thickness direction of the twisted liquid crystal layer.
The long axis direction of the liquid crystal molecules at the position of / 2 is substantially the same.

According to a fifth aspect of the present invention, there is provided the reflective liquid crystal display device, wherein the uneven reflection film has no unevenness period or a long azimuth is substantially in the vertical direction of the liquid crystal display device, and the liquid crystal is twisted between the upper and lower substrates. The liquid crystal display device is characterized in that the major axis direction of the liquid crystal molecules at a position substantially half of the thickness direction of the layer is oriented substantially in the lateral direction of the liquid crystal display device.

According to a sixth aspect of the present invention, at least one optical phase compensating member is provided between the polarizer and the liquid crystal element.

[0018]

Embodiments of the present invention will be specifically described below with reference to the drawings. << Embodiment 1 >> As a first embodiment, a liquid crystal display device using an uneven reflector including a mirror surface portion will be described below. FIG. 2 is a sectional view of the reflective liquid crystal display device 51 according to the embodiment of the present invention. The liquid crystal display device 51 includes a pair of transparent glass substrates 11 and 52.
Predetermined irregularities are formed on the top, aluminum,
A reflecting plate 17 is formed by depositing a reflecting metal film 16 made of a metal material such as nickel, chromium or silver. On the reflective metal film 16, an alignment film 53 for aligning the liquid crystal layer is formed.

On the surface of the glass substrate 52 facing the glass substrate 11, a transparent electrode 54 made of ITO (indium tin oxide) or the like is formed. An electric field is applied to the liquid crystal layer 55 by the reflective metal film 16 and the transparent electrode 54. An orientation film 56 is formed by covering the glass substrate 52 on which the transparent electrode 54 is formed, and the glass substrates 11 and 52 facing each other are formed.
Is sealed with a sealing material 57 described later.

Between the alignment films 53 and 56, a liquid crystal layer 55
Rubbing treatment is performed so as to obtain a twist orientation.
The liquid crystal layer 55 includes a liquid crystal 58 and a liquid crystalline polymer 59. On the opposite side of the glass substrate from the liquid crystal layer 52, for example, a polarizing plate 60 having a single transmittance of 48% is arranged.

FIG. 1 is a schematic diagram showing an example of the uneven structure (shaded portions indicate convex portions) of a reflector and the orientation of liquid crystal molecules in a liquid crystal layer in a liquid crystal display device 51 according to the present invention. The liquid crystal molecules are twist-aligned between the upper substrate and the lower substrate in the liquid crystal layer, and the direction of the long axis of the liquid crystal molecule at a position １ ／ of the thickness direction of the liquid crystal layer is almost equal to that of the liquid crystal display device. Lateral (90
Degrees-270 degrees).

On the other hand, the concave / convex reflector is formed so that the period of the concave / convex becomes longer (or no longer exists) in a substantially vertical direction (direction of 0-180 degrees) of the liquid crystal display device. Therefore, 1/1 of the thickness direction of the liquid crystal layer twist-aligned between the substrates.
The direction of the long axis of the liquid crystal molecules at the position 2 and the long (or no) azimuth around the unevenness of the uneven reflection plate are substantially perpendicular to each other.

Here, FIG. 1 will be described in comparison with the case where the liquid crystal layer of FIG. 2 is twisted at 40 degrees. Reflector 17
A liquid crystal layer 55 is sandwiched on the substrate, and the upper and lower substrates of the liquid crystal molecules are aligned along the axis shown in FIG.
The liquid crystal molecules of the liquid crystal layer are twist-aligned by this alignment treatment. Then, 4 is set so that θ1 = θ2 = 20 degrees.
The liquid crystal molecules which are twist-aligned by 0 degrees and located at a position １ ／ in the thickness direction of the cell are oriented in the direction of φ = 90 degrees.
With respect to such a liquid crystal layer, the concave / convex reflector under the liquid crystal layer is arranged such that the azimuth of the long period of the concave / convex is substantially perpendicular to the long axis direction of the liquid crystal molecules located at a half position in the cell thickness direction. Have been. As another example, when the liquid crystal layer is twist-aligned by 90 degrees, the liquid crystal layers are arranged so that θ1 = θ2 = 45 degrees. In the present invention, it is sufficient that θ1 and θ2 are almost equal, and it is not necessary to strictly match them.

Here, the manufacturing process of the once-coated reflector in the first embodiment will be described in detail with reference to FIG. As shown in FIG. 3A, for example, OFPR-800 (manufactured by Tokyo Ohka Co., Ltd.) as a resist material is preferably applied on one surface of a glass (trade name: 7059 Corning) substrate 11 having a thickness of 1.1 mm, preferably from 500 rpm to 3000 rpm.
Spin coat with. In this embodiment, the resist layer 12 is applied at 1000 rpm for 30 seconds to form a resist layer 12 having a thickness of 4 μm. Next, as shown in FIG. 3B, after prebaking at 90 ° C. for 30 minutes, the photomask 1 on which a predetermined pattern is formed is formed.
3 was arranged, exposed and developed (NMD-3, 2.38%, manufactured by Tokyo Ohka Co., Ltd.) to form fine irregularities 14 on the surface as shown in FIG.

When the unevenness 14 on the glass substrate 11 is heat-treated at preferably 120 to 250 ° C., a smooth uneven surface 15 with sharp corners is formed as shown in FIG. In this embodiment, the heat treatment was performed at 200 ° C. for 30 minutes. Further, as shown in FIG. 2D, a metal thin film 16 was formed on the substrate 11 on which the uneven portions 15 were formed. Examples of the metal thin film include Al, Ni, Cr, and Ag. The thickness of the metal thin film is suitably about 0.05 to 0.5 μm. In this embodiment, the metal thin film 16 is formed by vacuum-depositing Ag. Thus, the reflection plate 17 was obtained.

FIG. 4 shows a method for measuring the reflection characteristics of the reflector. When the reflector 17 is used in an actual liquid crystal display device, a cell configuration in which the surface of the reflector 17 and the liquid crystal layer are in contact with each other is assumed,
Since both the liquid crystal layer and the glass substrate have the same refractive index of about 1.5, the glass substrate 11 is placed on the reflection plate 17 with a refractive index of 1.
The UV-curable adhesive 4 of No. 5 was used for measurement.

As shown in FIG. 4, the measurement of the reflectance characteristics
This is performed by detecting the reflected scattered light among the light incident on the reflection plate with a photomultimeter. On the reflector,
The incident light is incident on the normal with an angle θ and a rotation angle φ in the plane of the reflector. Photomultimeter is metal thin film 1
6 is fixed in the direction of the normal line of the reflector 17 passing through the point where the incident light is irradiated. Incident angle θ of incident light and in-plane angle φ
The reflection characteristics were obtained by measuring the intensity of the scattered light of the incident light by the metal thin film 16 while changing.

The shapes of the concavities and convexities used in this embodiment are fine ellipses, rectangles, and stripes, which are shown in FIGS. 5A to 5C together with the coordinate axes in the plane of the reflector. The unit of the numerical value shown in the figure is μm. 6A to 6C show the reflection characteristics corresponding to the symbols of the reflector.

FIG. 6 shows the reflection intensity of light incident at an incident angle θ = 30 ° with respect to the normal as a function of the rotation angle φ in the plane of the reflector. From FIG. 6, it can be seen that the reflection intensity can be significantly increased in the direction having the straight sides of the minute irregularities formed on the surface, while if the irregularities have a curved surface, the in-plane rotation angle φ It can be seen that the reflection intensity dependency is reduced.

Further, it was confirmed that the inclination angle of the unevenness can be freely controlled by appropriately selecting the type and thickness of the photosensitive resin and the heat treatment temperature, thereby controlling the incident angle θ dependence of the reflection intensity. ing. Also, by changing the ratio of the occupied portion (the concave portion of the reflection plate), the size of the specular reflection component can be controlled.

FIG. 7 is a process chart showing a procedure for producing the reflection type liquid crystal display device 51. In step a1, a reflective film is formed on the surface of the substrate 11. The reflection electrode 16 is, for example,
It is formed by depositing a high-reflectance, low-resistance metal member such as Al or Ag by sputtering or vapor deposition.
In order not to have the depolarization property, it is necessary that the film formation temperature, the film formation rate, and the like be controlled and the surface be formed into a mirror surface. Further, the film thickness needs to be set in a range where the reflectance is sufficient and the resistance is low.
The thickness is preferably about 0.05 to 0.5 μm. In this case, the reflection film has both functions as an electrode for applying an electric field to the liquid crystal and a reflection film for reflecting incident light.

In step a2, an alignment film 53 made of a polyimide resin is formed on the reflection film 17 and rubbed. A polyimide resin film is formed on the substrate 11 by a printing method, and baked at 200 ° C. for 1 hour. For example, SE150 (manufactured by Nissan Chemical Industries, Ltd.) that aligns the liquid crystal parallel to the substrate was used. Thus, an alignment film 53 is formed. After that, a rubbing treatment for aligning the liquid crystal layer is performed.

In step a3, the transparent electrode 5
4 are formed. In this embodiment, the transparent electrode 54 made of ITO (indium tin oxide) or the like is formed by a sputtering method.

In step a4, an alignment film 56 is formed on the transparent electrode 54. The alignment film 56 is formed in the same manner as in the step a2. The rubbing direction is determined so that the upper and lower substrates 11 and 52 are twist-aligned by 40 degrees as an example.

In step a5, the substrate 11 and the substrate 52 are bonded. When the substrate 11 and the substrate 52 are combined, a spacer having a diameter of 3 μm is scattered between the substrates 11 and 52 to fix the thickness of the liquid crystal layer. The liquid crystal layer 55 is bonded with the sealing material 57 so that the glass substrates 11 and 52 face each other.

In step a6, the liquid crystal 58 and the UV-curable liquid crystal were mixed at a weight ratio of 90:10, and vacuum-injected into the cell having a cell thickness of 3 μm manufactured in step a5. In the liquid crystal / polymer composite layer 55, a nematic liquid crystal 58 having a positive dielectric anisotropy Δε, for example, Z
LI-1557Δn = 0.12 was used. A UV-curable liquid crystal before polymerization was used as a liquid crystal polymer material to be mixed therewith. The UV-curable liquid crystal exhibits a liquid crystal layer at room temperature, is oriented in the same manner as a normal liquid crystal material, and is polymerized and cured by irradiating ultraviolet rays while maintaining the arrangement of liquid crystal molecules, to form a liquid crystalline polymer 59. After that, before UV irradiation
The cured liquid crystal and after UV irradiation are called liquid crystalline polymers.

In step a7, an ultraviolet ray having an intensity of 10 mW / cm ² was irradiated for 300 seconds, and only the UV-curable liquid crystal was cured to form a liquid crystal / polymer composite layer 55. The twist angle of the nematic liquid crystal is 40 degrees, and the product of the birefringence of the liquid crystal and the thickness of the liquid crystal layer (hereinafter referred to as Δnd) is 0.360 μm.
The extraordinary refractive index and the ordinary refractive index of the liquid crystal and UV-curable liquid crystal are selected to be the same. However, it has been confirmed that almost the same effect can be obtained even when different refractive indices are used depending on manufacturing conditions. In step a8, the substrate 5
The polarizing plate 60 was attached to 2 to produce a reflection type liquid crystal display device 51.

Here, the optical arrangement of the polarizing plate and the liquid crystal layer in the reflection type liquid crystal display device manufactured as described above is defined as shown in FIG. FIG. 8 is a view of the reflective liquid crystal display device observed from above in FIG. That is, the orientation direction of the liquid crystal molecules on the upper substrate 3 side in the liquid crystal / polymer composite layer 55 is R1, and the angle at which the axial direction P0 of the transmission axis of the polarizing plate is counterclockwise from the orientation direction R1 is β.
Further, the alignment direction R1 (the direction of the arrow is the rubbing direction) and the liquid crystal molecules R2 of the reflection surface 16 (the direction of the arrow is the rubbing direction).
And the torsion angle is positive when the counterclockwise direction is positive. In the present embodiment, β is set to 20 degrees and ψ is set to 40 degrees.

Next, a circuit to be operated will be described with reference to FIG. The reflective metal film 16 and the transparent electrode 54 include
One of the scanning circuit 16 and the data circuit 17 is connected to each. The scanning circuit 91 and the data circuit 92 control the reflective metal film 16 based on display data corresponding to display contents under the control of a control circuit 93 such as a microprocessor.
Then, a signal is transmitted to the transparent electrode 54 to realize display.

FIG. 10 shows a liquid crystal display device 51 according to this embodiment.
FIG. FIGS. 11A and 11B to FIGS. 13A and 13B show the liquid crystal display device 5 of the present embodiment.
6 is a graph showing the reflection characteristic of No. 1. FIG. 11 shows FIG.
FIG. 12 shows the reflector shown in FIG. 5B, and FIG.
FIG. 3 shows a measurement result of the reflection plate shown in FIG. FIG.
In FIGS. 1 to 13A, light inclined at an angle of 30 degrees with respect to the normal direction of the liquid crystal display device 51 was incident, and the reflectance in the normal direction was measured. On the other hand, in the measurement in FIG. 11B to FIG. 13B, similarly, light inclined from the azimuth of φ = 0 by an angle of 30 degrees with respect to the normal direction of the liquid crystal display device 51 is incident, and the light receiving angle is set to 0 to 0. The measurement was performed while varying up to 60 degrees. In addition, a standard white plate made of alumina was used as a reference member for determining the reflectance and the contrast ratio at this time.

According to the experimental results shown in FIGS. 10 to 13, in this embodiment, light incident from all directions can be used efficiently, so that a bright display can be obtained regardless of the lighting environment. Also, the viewing angle of the display was sufficient.
For example, in a liquid crystal display device in which the reflector shown in FIG. 5A having stripe-shaped irregularities and the above-described polymer-dispersed liquid crystal layer are combined, as shown in FIGS.
%, And the maximum contrast ratio was 90 (a value for light incident from a direction inclined by an angle of 30 degrees with respect to the normal direction of the liquid crystal display device 51).

That is, the reflection intensity of the reflection plate is reproduced by using the settings of the reflection plate of the reflection type liquid crystal display device according to the present invention, and by changing the shape of the surface unevenness, the ratio between the vertical and horizontal pitches, and the shape. It can be understood that the control can be performed freely and freely, and that it is effective for extracting the reflected light at a desired angle.

FIG. 14 is a diagram for explaining the operation of the liquid crystal display device 51 of the present embodiment. For convenience of explanation, the liquid crystal display device 51 is shown in an exploded manner. The linearly polarized light transmitted through the polarizing plate 60 is incident on the liquid crystal / polymer composite layer 55 twisted by 40 degrees between the upper and lower substrates. The linearly polarized light passes through the liquid crystal / polymer composite layer, is converted to circularly polarized light on the reflection surface, and is reflected by the reflection plate 17 to be circularly polarized light in the opposite direction. Subsequently, the liquid crystal / polymer composite layer 5 is again formed.
5, the plane of polarization becomes 90 degree-converted linearly polarized light, and is absorbed by the polarizing plate 60. For this reason, the display of the reflective liquid crystal display device 51 is a black display without scattering. Since the reflection plate used in the present embodiment preserves the polarization state, a good black state can be obtained. Such a change in polarization occurs under limited conditions, which is described in detail in JAPAN DISPAY '89, p.192.

The optical properties required of the liquid crystal layer 55 are as follows: when no voltage is applied, the liquid crystal layer 55 becomes circularly polarized light after passing therethrough in response to the incidence of linearly polarized light. The two reasons are that the polarization plane is rotated by 90 degrees when passing. As a result of intensive studies, the present inventors have confirmed that a mixed system of a liquid crystal and a UV-curable liquid crystal matrix also satisfies the above conditions.

On the other hand, when a voltage is applied, only the liquid crystal is oriented perpendicular to the electrodes, so that the refractive index of the liquid crystal is close to the ordinary light refractive index, and the difference in the refractive index from the UV-curable liquid crystal increases. Although it is in a scattering state, the scattered light maintains polarization. Therefore, most of the scattered light can pass through the polarizer 60, and the display state of the present device becomes a so-called bright state. On the other hand, the cured liquid crystalline polymer 59 does not respond to voltage. In this bright state, since the liquid crystal layer 55 is in a white scattering state,
The possibility of so-called reflection from the surroundings is small,
So-called visibility is hardly reduced.

In this embodiment, since the polymer dispersed liquid crystal layer twisted by 40 degrees is used, light incident from the azimuths of 0 degrees and 180 degrees is efficiently scattered by the polymer dispersed liquid crystal layer, Light incident from the 90-degree and 90-degree directions is efficiently scattered by the uneven reflector underneath.
This schematic diagram is shown in FIG. Therefore, according to the reflective liquid crystal display device, light incident from all directions can be efficiently used, and a bright display can be obtained regardless of the lighting environment.

The ratio between the non-scattered light and the scattered light in the polymer-dispersed liquid crystal layer can be controlled by the mixing ratio of the liquid crystal and the UV-curable liquid crystal or the difference between the refractive indices thereof. It can be controlled freely by changing the shape, the ratio of the vertical and horizontal pitches, and the shape.

In the above-described embodiment, the shape of the irregularities is shown in FIG.
(A) to (c), using a pitch of 38 to 5
Although the case where the pitch is 3 μm and the height is 2 μm has been described, it has been confirmed that if the pitch is within 100 μm and the height is within 3 μm, the reflection characteristics can be controlled as in the present embodiment. Further, when the metal thin film on the reflection plate is arranged on the liquid crystal layer side, that is, at a position substantially adjacent to the liquid crystal layer as in the present embodiment, the height of the projections of the projections and depressions is the cell thickness. It is desirable that the inclination angle of the unevenness is smaller than that which does not disturb the alignment of the liquid crystal.

In the above embodiment, OFPR-800 (manufactured by Tokyo Ohka Co., Ltd.) was used as the resist material. However, the present invention is not limited to this. Any resin can be used.

For example, OMR-83, OMR-8
5, ONNR-20, OFPR-2, OFPR-83
0, OFPR-5000 (all manufactured by Tokyo Ohkasha), TF
-20, 1300-27, 1400-27 (sh
ipley), Photo Nice (Toray), RW1
01 (manufactured by Sekisui Fine Chemical Co., Ltd.), R101, R63
3 (all manufactured by Nippon Kayaku Co., Ltd.).

Further, as the substrate, a glass substrate is used in the present embodiment. However, a similar effect can be obtained with an opaque substrate such as a Si substrate. In this case, there is a merit that a circuit can be integrated on the substrate.

Further, in the reflection type liquid crystal display device of the present embodiment, since the surface of the reflection plate 17 on which the metal thin film 16 is formed is disposed on the liquid crystal layer side, parallax is eliminated and a good display screen can be obtained. Further, in the present embodiment, the metal thin film 16 of the reflection plate 17 also functions as a counter electrode, so that the method of manufacturing the display device is simplified.

Embodiment 2 Next, a second embodiment using a reflector (double coating) having a different pitch and smooth unevenness will be described. FIG. 16 is a cross-sectional view of the reflective liquid crystal display device 161 of the present embodiment. The reflection type liquid crystal display device 161 is a reflection type liquid crystal display device 5 according to the first embodiment.
1 is substantially the same as that of FIG. 1, but is characterized by forming smooth irregularities on the substrate 11. Liquid crystal display 16
1 includes a pair of transparent glass substrates 11 and 52, on which large projections 162 and small projections 163 in the form of stripes made of a synthetic resin material described later are formed, respectively. Stripe widths D1, D of projections 162, 163
2, for example, is set to 30 μm and 15 μm, and the interval D3 is set to, for example, at least 2 μm or more.

The smoothing film 164 is formed by covering these projections 162 and 163 and filling the recesses between the projections 162 and 163. The surface of the smoothing film 164 has protrusions 162, 1
Under the influence of 63, a smooth curved surface is formed. On the smoothing film 164, a reflective metal film 16 made of a metal material such as aluminum, nickel, chromium or silver is formed. The projections 162 and 163, the smoothing film 164, and the reflective metal film 16 on the glass substrate 11 constitute a reflector 165 as a light reflecting member. On the reflective metal film 16, an alignment film 53 is formed.

On the surface of the glass substrate 52 facing the glass substrate 11, a transparent electrode 54 made of ITO (indium tin oxide) or the like is formed. The reflective metal film 16 and the transparent electrode 54 form an electrode structure. An orientation film 56 is formed by covering the glass substrate 52 on which the transparent electrode 54 is formed, and the glass substrates 11 and 52 facing each other are formed.
Is sealed with a sealing material 57 described later. A liquid crystal / polymer composite layer 55 having the same configuration as that of the first embodiment is sealed between the alignment films 53 and 56. The liquid crystal of the glass substrate 52
On the side opposite to the polymer composite layer 55, a polarizing plate 60 having a single transmittance of 48% is disposed.

FIG. 17 is a cross-sectional view for explaining a manufacturing process of the reflection plate 165 shown in FIG. As the glass substrate, 11 (manufactured by Corning, trade name: 7059) was used. FIG. 17 (a)
As shown in FIG. 5, a photosensitive resin material such as OFPR-800 (trade name, manufactured by Tokyo Ohka Co., Ltd.) is spin-coated on a glass substrate 11 at 500 rpm to 3000 rpm, for example.
A resist layer 12 is formed. In the present embodiment, spin coating is preferably performed at 2500 rpm for 30 seconds, and a thickness of 1.5
A μm resist layer 12 is formed.

Next, the glass substrate 11 on which the resist film 12 has been formed is baked at 90 ° C. for 30 minutes.
As shown in FIG. 5, a photomask 13 having a stripe pattern formed thereon is arranged and exposed, and is developed with a developer composed of a 2.38% solution of NMD-3 (trade name, manufactured by Tokyo Ohka Co., Ltd.) as an example. As shown in FIG. 17C, large projections 162-1 and small projections 163-1 having different heights were formed on the surface of the glass substrate 11. The reason why two or more types of protrusions having different heights are formed is to prevent coloring of reflected light due to interference of light reflected at the tops and valleys of the protrusions.

The photomask 13 has, for example, a structure in which stripes having a stripe width of 5 μm and stripes having a width of 3 μm are alternately arranged, and the interval between the stripes is selected to be at least 2 μm or more. FIG. 17 (c)
Is heated at 200 ° C. for 1 hour to form protrusions 162 and 163 as shown in FIG.
Was slightly melted to form an arc.

Further, as shown in FIG.
7 (d), the same material as the photosensitive resin material is applied on the glass substrate 11 at the manufacturing stage of 1000 rpm to 3000 rpm.
Spin coat with m. In the present embodiment, preferably 200
Spin coat at 0 rpm. Thereby, each protrusion 16
The recess between the second and 163 is filled, and the surface of the formed smoothing film 164 can be formed into a relatively gentle and smooth curved surface.

Further, as shown in FIG. 17 (f), the surface of the smoothing film 164 is formed to have a thickness of 0.01 to 0.01, for example, using a thin metal film such as aluminum, nickel, chromium or silver.
It is formed to about 1.0 μm. In this embodiment, the reflective metal film 16 is formed by sputtering aluminum.
The reflection member 165 is formed as described above. FIG. 18 shows the pattern of the mask used in the present embodiment, and FIG. 19 shows its reflection characteristics.

Next, a polyimide resin film is formed on each of the glass substrates 11 and 52 and baked at 200 ° C. for 1 hour. Thereafter, a rubbing process for aligning the liquid crystal polymer composite layer 55 is performed. Thereby, alignment films 53 and 56 are formed. The sealing material 57 for sealing between the glass substrates 11 and 52 is formed, for example, by screen printing an adhesive sealing material mixed with a spacer having a diameter of 3.5 μm.

The reflecting plate 165 thus formed
And the glass substrate 3 on which the transparent electrode 54 and the alignment film 56 are formed.
A spacer having a diameter of 3 μm is scattered between 1 and 52 to fix the thickness of the liquid crystal layer. For the liquid crystal polymer composite layer 55, a material having the same configuration as that of the first embodiment was applied. Thereafter, ultraviolet irradiation is performed to perform phase separation between the liquid crystal and the liquid crystalline polymer. At this time, in the liquid crystal display device 161, the liquid crystal molecules are twist-aligned between the upper substrate and the lower substrate in the liquid crystal layer, and the long axis of the liquid crystal molecule is located at a position 厚 of the thickness direction of the liquid crystal layer. Is oriented substantially in the lateral direction of the liquid crystal display device (direction of 90 degrees to 270 degrees). On the other hand, the concavo-convex reflection plate is formed with concavities and convexities such that the period of the concavo-convex lengthens (or disappears) substantially in the vertical direction (direction of 0-180 degrees) of the liquid crystal display device.
Therefore, the direction of the long axis of the liquid crystal molecules at a position 方向 of the thickness direction of the liquid crystal layer twisted between the substrates and the long (or no) azimuth around the unevenness of the uneven reflection plate are substantially perpendicular to each other. ing. FIG. 20 shows the reflection characteristics of this liquid crystal display device.
(A) and (b). The measurement optical system is the same as in the first embodiment.

According to the experimental results according to the present embodiment, the reflectance in the normal direction at the time of applying a voltage was 50% at the maximum, and the maximum contrast ratio was 60. A standard white plate of alumina was used as a reference member for determining the reflectance and the contrast ratio at this time. Here, the operation principle of the liquid crystal layer 55 is the same as that of the first embodiment. In the case of the present embodiment, in addition to the scattering property of the reflective film, the scattering of the liquid crystal layer also contributes to the brightness of the display, so the height of the unevenness is 0.5 μm or less, which is smaller than that of the conventional reflector. it can. Although the maximum contrast is lower than in the first embodiment, the maximum contrast is higher than 15% even when light is incident from any direction, which indicates that there is a merit of widening the viewing angle.

In the reflection type liquid crystal display device 161 of this embodiment, since the surface of the reflection plate 165 on which the reflection metal film 16 is formed is disposed on the liquid crystal layer 55 side, the parallax when observing the liquid crystal display device 161 is reduced. Thus, a good display screen can be obtained. Further, when the liquid crystal display device 161 is configured to be driven by an active matrix, the liquid crystal display device 161 may be used as a pixel electrode connected to a thin film transistor used as a switching element or a non-linear element having an MIM (metal-insulating film-metal) structure. It has been confirmed that good display quality can be realized as described above.

Embodiment 3 Next, a reflection type liquid crystal display device driven by a simple matrix will be described below as a third embodiment. 19 between glass substrates 11 and 52
A nematic liquid crystal twisted three times (for example, trade name SD-4107 manufactured by Chisso Corporation) was used as a liquid crystal layer. Other configurations were the same as those in FIG.

The alignment films 53 and 56 made of SE-150 (manufactured by Nissan Chemical Industries, Ltd.) are formed on the surfaces of the substrates 11 and 52, respectively, and a rubbing alignment process is performed. Nematic liquid crystal 58 having a positive dielectric anisotropy obtained by adding an appropriate amount of a left-handed chiral agent S-811 (manufactured by Merck Japan) between both substrates 11 and 52.
(Trade name: SD-4107 manufactured by Chisso Corporation) and a liquid crystal layer composed of UV-curable liquid crystal, and the layer thickness is 3.0 μm.
The liquid crystal device for driving according to the present invention was manufactured by sandwiching the liquid crystal / polymer composite layer 55 as above. When no voltage is applied, the liquid crystal layer 55 has a left-handed twist of 193 degrees.

The liquid crystal display device thus obtained is reduced to 1/4
When multiplex driving is performed at 80 duty, the mode becomes a normally black mode, a contrast ratio of 30: 1 is obtained in front, and a contrast ratio of 5: 1 or more at an incident angle of 20 ° or less in both vertical and horizontal directions. An extremely wide viewing angle dependence was obtained.

According to such a configuration, the steepness of the electro-optical characteristics is increased, and simple matrix driving is possible. According to the same principle as in the first embodiment, a dark state without scattering and a bright state of scattering state are realized. When the reflectance was measured with the applied voltage corresponding to the selected pixel, 1
It was found that the reflectance was as high as 32%.

Embodiment 4 As a fourth embodiment, a nematic liquid crystal twisted 45 degrees between glass substrates 11 and 52 (for example, trade name SP-49 manufactured by Chisso Corporation)
66) is used as a liquid crystal layer and the cell thickness is set to 3.0 μm. As other components, the same configuration as the configuration shown in FIG. 1 was used.

On the surfaces of the substrates 11 and 52, alignment films 53 and 56 made of SE-150 (manufactured by Nissan Chemical Industries, Ltd.) are formed, respectively, and a rubbing alignment process is performed. Nematic liquid crystal 58 having a positive dielectric anisotropy obtained by adding an appropriate amount of a left-handed chiral agent S-811 (manufactured by Merck Japan) between both substrates 11 and 52.
(Trade name: SP-4966, manufactured by Chisso Petrochemical Co., Ltd.) and a liquid crystal layer made of UV-curable liquid crystal were filled and sandwiched as a liquid crystal layer 55 having a liquid crystal layer thickness of 3 μm to produce a driving liquid crystal display device 51 of the present invention.

The liquid crystal / polymer composite layer 55 has a left-handed twist of 45 degrees when no voltage is applied. In this embodiment, β is 22.5 degrees and ψ is 45 in the optical arrangement diagram shown in FIG.
It is set every time.

Using the optical system shown in FIG. 4, the reflectance of the thus obtained liquid crystal display device in the in-plane direction in the bright state was measured. Then, it was found that the brightness was maximized in the rubbing direction R1 of the upper substrate + 90 degrees + twist angle / 2 of the liquid crystal layer. In the present embodiment, since the twist angle of the liquid crystal layer is 45 degrees, the brightest display was obtained in the azimuth of R1 + 112.5 degrees.

When driven in this direction, a normally black display was obtained, and a contrast ratio of 30: 1 was obtained from the front. According to the same principle as in the first embodiment, a dark state without scattering and a bright state of scattering state were realized.

Fifth Embodiment Next, a reflection type liquid crystal display device in which an optical phase difference compensating plate is inserted in the first embodiment will be described below as a fifth embodiment. As shown in FIG. 21, a nematic liquid crystal (trade name: SP-4966, manufactured by Chisso Corporation) twisted between 80 and 95 degrees between glass substrates 11 and 52 and a UV-curable liquid crystal as a liquid crystal layer are used as a liquid crystal layer. An optical compensator 212 was inserted between the liquid crystal layer and the liquid crystal layer, thereby producing a reflection type liquid crystal display device 211. Other configurations are the same as the first embodiment.

A nematic liquid crystal having a positive dielectric anisotropy (manufactured by Merck Japan Co., Ltd.) obtained by adding an appropriate amount of a left-handed chiral agent S-811 (manufactured by Merck Japan Co., Ltd.) between both substrates 11 and 52.
ZLI-3103, Δn = 0.07) and UV-curable liquid crystal were mixed at a weight ratio of 90:10, filled with a liquid crystal composition, and sandwiched with a layer thickness of 3 μm. After that, the liquid crystal was irradiated with ultraviolet rays, and the liquid crystal and the liquid crystal polymer were phase-separated to form the liquid crystal layer 55 of the present invention. In the present embodiment, for example, the liquid crystal layer 5
Reference numeral 5 denotes a left-twisted 80-degree twist or 95-degree twist configuration. The method for manufacturing the liquid crystal layer is the same as that of the first embodiment.

The polycarbonate is stretched in a certain direction on the upper substrate 52 of the drive cell thus obtained, and the stretching axis (slow axis)
Retardation plate 212 (R = 160 nm and 150 n
m) was combined to produce a liquid crystal display element 211 of the present invention.

The conditions of the liquid crystal layer in the case of the constitution of 80 degree twist or 95 degree twist are shown in the following conditions A and B.
Here, the optical configurations of the polarizing plate, the optical phase compensation film, and the liquid crystal layer in the liquid crystal display device thus configured are adjusted as shown in FIG. Here, γ is an angle formed between the slow axis direction S of the optical phase compensation film and the transmission axis P0 of the polarizing plate in a counterclockwise direction when the liquid crystal display device is viewed from above.

[0078] FIG. 23 is a graph showing the spectral characteristics in the front direction when no voltage is applied and when a voltage is applied in the case of the 80-degree twist (condition A) of the reflective liquid crystal display device. By inserting the optical compensation film, the reflection on the short wavelength side and the long wavelength side at the time of dark display was reduced, and good display with high contrast was realized.

In this embodiment, a stretched film made of polycarbonate is used as the optical compensator 212. However, the present invention is not limited to this, and examples thereof include polyvinyl alcohol (PVA) and polymethyl methacrylate (PMMA). Can be used. Further, a biaxial film in which the refractive index is changed in the thickness direction or a polymer liquid crystal film is also applicable to the present invention. When the liquid crystal display device thus obtained was statically driven, a normally black mode was obtained, and a contrast ratio of 100: 1 was obtained from the front.

In the reflection type liquid crystal display device 211 of this embodiment, the surface of the reflection plate on which the reflection metal film 16 is formed is the liquid crystal layer 55.
Since it is disposed on the side, parallax when observing the liquid crystal display device 211 is eliminated, and a good display screen is obtained.

Further, in the present embodiment, the liquid crystal / polymer composite layer 55 is made of a liquid crystal twisted by 80 degrees and a liquid crystal twisted by 95 degrees, and an optical retardation compensation film suitable for each is used. However, the present invention is not limited to this. However, any liquid crystal material having any twist angle can be used in the present invention as long as the liquid crystal layer has a characteristic that retardation can be controlled by an electric field.

Further, the liquid crystal display device of the present invention may be manufactured by using a nematic compensation liquid crystal cell in which liquid crystal molecules are arranged in a splay shape instead of the polycarbonate retardation plate 72 in the present embodiment. Good. The liquid crystal cell for compensation used here is an alignment film obtained by obliquely depositing SiO on the upper and lower substrates of glass. The pretilt angles of the upper and lower substrates are both 45 degrees, and the tilt direction of the upper and lower substrates (substrate plane direction). Has a difference of 180 degrees at the top and bottom, and here a liquid crystal layer sandwiched between ZLI-2293 (manufactured by Merck Japan), which is a nematic liquid crystal having a positive dielectric anisotropy. The thickness of the liquid crystal layer is about 3 μm.

The retardation value of this compensating liquid crystal cell with respect to the cell normal direction was measured by using an interference method and found to be 160 nm. Further, the compensating liquid crystal cell and the liquid crystal molecules were arranged such that the tilt direction (plane direction of the substrate) of the liquid crystal molecules was equal to the delay axis of the retardation plate in FIG. Further, a film in which a liquid crystalline polymer is twist-oriented is also applicable to the present invention.

Embodiment 6 A sixth embodiment in which a color filter layer is formed on a reflection type liquid crystal display device will be described below. FIG. 24 shows a reflection type liquid crystal display device 2 of the present invention.
41 shows a sectional view of FIG. The reflective liquid crystal display device 241 is configured in substantially the same manner as the reflective liquid crystal display device 51 of the first embodiment, but transmits red, green, and blue light on the reflective film 16 of the glass substrate 11. A color filter layer 242 of a pigment dispersion type is formed.

As shown in the figure, the color filter layer 242 has a red color filter, a green color filter and a blue color filter each corresponding to a single dot in one picture element, and a black matrix 243 is juxtaposed therebetween. ing.

In this embodiment, red, green, and blue color filters are arranged in a stripe shape as an example. A flattening film 244 was formed on the color filter layer 242, and a transparent electrode 245 was formed thereon, thereby forming a display electrode. The same configuration as in the first embodiment was used for the liquid crystal / polymer composite layer 55. In this embodiment, a pigment dispersion method is applied as an example of the color filter layer 242, and the color filter layer 242 is manufactured as follows.
First, a photosensitive colored resist in which a red pigment is uniformly dispersed in a transparent photosensitive resin is applied to the reflective surface 7 on the glass substrate 2.
Was formed and applied. In the present embodiment, a CR2 manufactured by Fuji Hunt Electronics Technology Co., Ltd. is used.
2,000 at 650 rpm by a spin coating method.
m was formed. Thereafter, the film was prebaked at 80 ° C., exposed and developed using a predetermined mask, and finally baked at 220 ° C. for 30 minutes to form a red pattern.

Further, CG2000, CB2000, C manufactured by Fuji Hunt Electronics Technology Co., Ltd.
Using K2000, green, blue and black patterns were formed in the same process, and a color filter layer 232 was formed.

According to the present embodiment, by forming a color filter layer on one substrate, a multi-color or full-color display with a wide color reproducibility range can be realized. FIG. 25 is a diagram showing chromaticity coordinates of each color of RGB of the reflection type liquid crystal display device manufactured according to the present embodiment. According to FIG. 25, in the reflection type liquid crystal display device according to the present embodiment, it is understood that a good color display having a sufficiently wide color reproduction area and a contrast of 10 or more is possible.

In this embodiment, an example of an absorption type color filter has been described. However, an organic volume hologram optical color filter or an inorganic dichroic mirror as a light reflection type color filter instead of the reflection surface 16 is used in the present invention. Application is possible. However, in this case, it is necessary to provide an absorption layer on the back of the light reflection type color filter. Also, it has been confirmed that the same effect can be obtained even when the light absorbing type color filter 242 is formed on the upper substrate 52.

[0090]

As described above, according to the present invention,
By using a composite of liquid crystal and liquid crystalline polymer for the liquid crystal layer sandwiched between one polarizing plate and the reflective film and combining it with an anisotropic reflector, the polymer dispersed liquid crystal in the bright state Due to the white turbid state, there can be obtained a reflection type liquid crystal display device which does not cause so-called reflection of surroundings, has no parallax, has a wide viewing angle, and has sufficient brightness without coloring.

Further, since the driving voltage is relatively low and a backlight is not required, there is an effect that the power consumption is low and the visibility is excellent as compared with a liquid crystal display device having a backlight.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a concavo-convex structure of a reflection plate and directions of liquid crystal molecules of a liquid crystal layer.

FIG. 2 is a sectional view of a reflective liquid crystal display device 51 according to the present invention.

FIG. 3 is a manufacturing process diagram of an uneven reflection film used in the reflection type liquid crystal display device 51.

FIG. 4 is an explanatory diagram of a method for measuring optical characteristics of the reflection type liquid crystal display device 51.

5 (a), (b), and (c) are shapes of three types of projections formed on a reflection plate used in the reflection type liquid crystal display device 51. FIG.

FIG. 6 is a graph showing reflection characteristics of three types of reflectors shown in FIGS. 5 (a), 5 (b) and 5 (c).

FIG. 7 is a manufacturing process diagram of the reflective liquid crystal display device 51.

FIG. 8 is an explanatory diagram of an optical arrangement of the reflection type liquid crystal display device 51.

FIG. 9 is an explanatory diagram of a drive system of the reflection type liquid crystal display device 51.

FIG. 10 is an applied voltage-reflectance characteristic diagram of the reflection type liquid crystal display device 51.

11A is an explanatory diagram of the incident azimuth angle dependence of the reflectance of the reflective liquid crystal display device 51 by the reflector shown in FIG.
FIG. 9B is an explanatory diagram of the dependence of the reflectance on the light receiving angle.

12 (a) is a diagram illustrating the dependence of the reflectance of the reflective liquid crystal display device 51 on the incident azimuth angle by the reflector shown in FIG. 5 (b).
FIG. 9B is an explanatory diagram of the dependence of the reflectance on the light receiving angle.

13A and 13B are explanatory diagrams of the dependence of the reflectance of the reflective liquid crystal display device 51 on the incident azimuth angle by the reflector shown in FIG.
FIG. 6B is an explanatory diagram (b) of light-receiving angle dependence.

FIG. 14 is an explanatory diagram of a display operation of the reflection type liquid crystal display device 51.

FIG. 15 is an explanatory diagram of a display principle of the reflective liquid crystal display device 51 according to the present invention.

FIG. 16 is a sectional view of a reflective liquid crystal display device 161 according to the second embodiment.

FIG. 17 is a manufacturing process diagram of the uneven reflection film of the reflection type liquid crystal display device 161.

FIG. 18 is an explanatory diagram of a shape of a convex portion formed on a reflection plate used in the reflection type liquid crystal display device 161.

FIG. 19 is a graph showing reflection characteristics of a reflection plate used in the reflection type liquid crystal display device 161.

FIGS. 20A and 20B are an explanatory diagram (a) of an incident azimuth angle dependency of a reflection characteristic of the reflective liquid crystal display device 161 and an explanatory diagram (b) of a light receiving angle dependency.

FIG. 21 is a sectional view of a reflective liquid crystal display device 211 according to a fifth embodiment.

FIG. 22 is an explanatory diagram of an optical arrangement of the reflection type liquid crystal display device 211.

FIG. 23 is a characteristic diagram showing a reflection spectrum of the liquid crystal display device 211.

FIG. 24 is a sectional view of a reflective liquid crystal display device 241 according to a sixth embodiment.

FIG. 25 is a chromaticity coordinate characteristic diagram of a color display obtained by the reflection type liquid crystal display device 241.

[Explanation of symbols]

 11, 52 Glass substrate 12 Resist 13 Photo mask 14 Irregularities 15 Smooth irregularities 16 Metal thin film electrode 17, 145 Reflector 51, 161, 211, 241 Reflective liquid crystal display device 53, 56 Alignment film 54 Transparent electrode 55 Liquid crystal layer 57 Seal Material 58 Liquid crystal 59 Liquid crystalline polymer 60 Polarizer 91 Scanning circuit 92 Data circuit 93 Control circuit 162, 163 Projection 164 Smoothing film 212 Optical compensator 242 Color filter layer 243 Black matrix 244 Flattening film 245 Transparent electrode

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hajime Hiraki 22-22 Nagaikecho, Abeno-ku, Osaka-shi, Osaka F-term (reference) 2H042 BA03 BA15 BA20 2H089 HA02 HA04 JA04 KA04 KA08 QA16 SA04 SA07 TA04 2H091 FA08X FA08Z FA11X FA11Z FA14Y FA16Y FB08 FC02 FD09 GA02 GA06 GA09 JA01 JA02 KA02 KA03 LA03 LA16 LA19

Claims (6)

[Claims] At least one polarizer on the light incident side of a liquid crystal element, an insulating substrate having at least a transparent electrode formed thereon, a light reflecting member having a light reflecting surface formed thereon, A reflective liquid crystal display device having a liquid crystal layer sealed between a reflective member and a liquid crystal layer in which liquid crystal molecules and a liquid crystalline polymer are both twisted, and a linearly polarized incident light enters a dark display, On the reflection surface, the light becomes circularly polarized light, and on the emission surface after the reflection, the light becomes linearly polarized light in which the incident light and the 90-degree polarization plane are rotated,
In a reflection type liquid crystal display device in which a linearly polarized incident light enters the bright display, and becomes a scattered light that passes through only a polarization component in the same direction as the incident light on the exit surface after reflection, the light reflecting member has an uneven shape, The concave-convex shape has an average concave-convex period that differs depending on the orientation in the substrate plane, and the concave-convex reflective film has no or long irregularity period and a position substantially half the thickness direction of the liquid crystal layer twisted between the upper and lower substrates. A long axis direction of the liquid crystal molecules is substantially perpendicular to the liquid crystal molecules. 2. The reflection type liquid crystal display device according to claim 1, wherein the twist angle of the liquid crystal layer in which both the liquid crystal molecules and the liquid crystalline polymer are twisted is within 100 degrees. 3. The reflection type liquid crystal display device according to claim 1, wherein an angle between a transmission axis of the polarizing plate and an alignment direction of the liquid crystal molecules on the incident side is substantially parallel. 4. The direction of the transmission axis of the polarizing plate and the major axis direction of the liquid crystal molecules between the upper and lower substrates at a position substantially half the thickness direction of the twisted liquid crystal layer of the liquid crystal molecules. 3. The reflection type liquid crystal display device according to claim 1, wherein the reflection type liquid crystal display device is substantially the same. 5. An azimuth without or with a long azimuth period of the rugged reflection film is substantially in a vertical direction of the liquid crystal display device, and
2. The liquid crystal display device according to claim 1, wherein the major axis direction of the liquid crystal molecules at a position substantially half the thickness direction of the twisted liquid crystal layer between the upper and lower substrates is oriented substantially in the lateral direction of the liquid crystal display device.
5. The reflection type liquid crystal display device according to any one of items 4 to 4. 6. The reflection type liquid crystal display device according to claim 1, wherein at least one optical phase compensation member is provided between the polarizer and the liquid crystal element.