JPH11249109A - Reflection type liquid crystal device and electronic equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a novel reflection type liquid crystal device, with which the contrast of display can be improved, the reduction of visibility caused by dazzling due to the incidence of light into eyes or the imprinting of the background can be suppressed and visibility can be improved, concerning the reflection type liquid crystal device provided with a polymer distributed liquid crystal layer. SOLUTION: On the surface of a reflecting electrode 24 formed on the inner surface of a back side substrate 20, a photo-responsible film 25 composed of photochromic materials is formed. This photo-responsible film 25 is colored in black in the light transmissible state of a liquid crystal layer 30 and made transparent in the light scattering state of the liquid crystal layer 30. Thus, since this device is operated to make a color tone darker in the case of making the display style of the liquid crystal layer dark by improvement in the light transmittance of the liquid crystal layer and to prevent the light chrominance or lightness of the display from being disturbed in the case of making the display style light by the reduction of light transmittance caused by light scattering, the contrast of display due to the liquid crystal layer can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a reflection type liquid crystal device, and more particularly to a structure of a liquid crystal device having a polymer dispersed type liquid crystal layer.

[0002]

2. Description of the Related Art Conventionally, as a reflection type liquid crystal device, a polarizing plate is disposed on a front side and a rear side of a liquid crystal cell including a liquid crystal layer, respectively, as in a general TN type or STN type liquid crystal device, and a rear side is provided. In some cases, a reflection plate is disposed behind a polarizing plate. However, a reflection type liquid crystal device using such a polarizing plate captures external light into a liquid crystal cell, makes the display visible only with the reflected light, and emits external light and reflected light. At times, it is necessary to pass through two polarizers, so that a large light loss occurs, which causes a problem that the display is dark.

In order to reduce the drawback of the reflection type liquid crystal device that the display is dark, another type of liquid crystal device which enables display without using a polarizing plate has been developed. As this type of liquid crystal device, there is a liquid crystal device using a scattering mode in which display is performed by controlling a liquid crystal layer between a light scattering state and a light transmitting state by an electric field. In this liquid crystal device, a polymer-dispersed liquid crystal layer is formed, white display is realized by the light scattering state of the liquid crystal layer itself, and specular reflection light from the reflecting surface is observed by the light transmission state of the liquid crystal layer. Black display is realized by preventing the light from entering.

[0004]

However, in a liquid crystal device using the above-mentioned scattering mode, although the display can be made brighter because no polarizing plate is used, it is possible to switch between a light scattering state and a transmission state. In this case, there is a problem that it is difficult to increase the contrast ratio of the display. Particularly, in the light transmission state, black is displayed because reflected light is hardly emitted in a direction other than the emission direction of specularly reflected light from the reflecting surface, so that a black density cannot be sufficiently obtained. There is a point. In addition, in this light transmitting state, there is a problem that eyes are dazzled by direct regular reflection from the reflection plate, and visibility is deteriorated by a background reflected on the display surface.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a reflective liquid crystal device having a liquid crystal layer of a polymer dispersion type, which can enhance display contrast and reduce reflected light. It is an object of the present invention to provide a novel reflective liquid crystal device that can suppress a decrease in visibility due to dazzling due to entering an eye and a reflection of a background, and can improve visibility.

[0006]

In order to solve the above-mentioned problems, the present invention takes a measure that a polymer-dispersed liquid crystal layer in which a liquid crystal and a polymer are mutually dispersed is disposed between two substrates. The degree of light scattering of the liquid crystal layer is controlled by the state of application of an electric field to the liquid crystal layer, and in a reflective liquid crystal device having a reflective surface on the back side of the liquid crystal layer, the inside of the liquid crystal layer or the liquid crystal layer And between the reflective surface,
A light-responsive substance that is darkened when the light transmittance of the liquid crystal layer is high and is lightened or light-transmitted when the light transmittance of the liquid crystal layer is low due to light scattering is arranged. And

According to this means, by arranging the photoresponsive substance, when the light transmittance of the liquid crystal layer increases, the appearance on the reflecting surface becomes darker, and when the light transmittance of the liquid crystal layer decreases, the appearance on the reflecting surface decreases. Since the appearance of is lightened or the light transmittance is increased, when the light transmittance of the liquid crystal layer is increased and the display mode by the liquid crystal layer is darkened, the color tone becomes darker and light scattering occurs. When the light transmittance is lowered and the display mode is lightened, the lightness or brightness of the display is prevented from being hindered, so that the display contrast by the liquid crystal layer can be improved. In addition, when the light transmittance of the liquid crystal layer is increased, the dazzling and the reflection of the background due to the reflection surface are reduced by the dark-colored photoresponsive substance, so that the visibility can be further improved.

Incidentally, the photoresponsive substance is not only a substance which becomes transparent (light transmittance is increased) when the light irradiation amount is small, but also a substance which becomes lighter or lighter, for example, whitened. Is also good.

Here, it is preferable that the photoresponsive substance is made of a photochromic material which is transparent when the light irradiation amount is small and turns black when the light irradiation amount is large.
In this case, display contrast and visibility can be further improved.

In each of the above means, the photoresponsive substance may be formed as a thin film formed on the reflection surface.

Further, the photoresponsive substance may be formed in a minute shape dispersed in the liquid crystal layer.

In this case, it is preferable that the photoresponsive substance is arranged in the liquid crystal layer so as to be biased toward the rear substrate. The photoresponsive substance formed in a minute shape may be uniformly dispersed in the liquid crystal layer,
In particular, since the liquid crystal layer is disposed so as to be biased toward the rear side substrate, the amount of light reaching the light responsive material when the light transmittance of the liquid crystal layer is reduced can be reduced. And the contrast can be further improved.

Here, as a method for dispersing and disposing the photoresponsive substance formed in a minute shape, a method for dispersing the photoresponsive substance on the inner surface of one of the substrates together with a spacer for regulating the distance between the substrates, or a method for dispersing the photoresponsive substance together with a liquid crystal material There is a method of injecting into a liquid crystal cell. In addition, as a method of disposing the photoresponsive substance toward the rear substrate, the photoresponsive substance may be adsorbed after being sprayed on the inner surface of the rear substrate (if there is a formed film on the inner surface), or may be adsorbed on the liquid crystal layer. There is a method of selecting a material having a higher specific gravity than that of the material and causing it to settle and adsorb it.

Further, according to the present invention, a polymer-dispersed liquid crystal layer in which a liquid crystal and a polymer are dispersed in each other is disposed between two substrates, and the liquid crystal layer has at least light by a structure for applying an electric field to the liquid crystal layer. In a reflective liquid crystal device that is configured to be controllable between a transmission state and a light scattering state and has a reflective surface on the back side of the liquid crystal layer, the reflective liquid crystal device may include a liquid crystal layer inside or between the liquid crystal layer and the reflective surface. In addition, a light-responsive substance is provided which becomes darker when the liquid crystal layer is in a light transmitting state, and becomes lighter or has a higher light transmittance when the liquid crystal layer is in a light scattering state.

According to this means, when the liquid crystal layer is in the light transmitting state, the light-responsive substance is made darker to further darken the display, and when the liquid crystal layer is in the light scattering state, Since the light-responsive substance becomes lighter in color or has a higher light transmittance and does not hinder the lightness or brightness of the display, it is possible to realize bright and dark display with high contrast and the liquid crystal layer is in a light transmitting state. In this case, it is possible to reduce the dazzling and the reflection of the background due to the reflected light.

[0016]

Next, an embodiment according to the present invention will be described with reference to the accompanying drawings. FIG. 1 is a schematic longitudinal sectional view showing a schematic configuration of a first embodiment of the reflective liquid crystal device according to the present invention. In this embodiment, a liquid crystal layer 30 is sealed between a transparent front substrate 10 and a rear substrate 20 made of inorganic glass by a sealing material (not shown).

A color filter 1 is provided on the inner surface of the front substrate.
No. 1 is formed by arranging a known colored layer such as a pigment dispersion type in a predetermined pattern, and coating a transparent protective film thereon. On the color filter 11, I
Transparent electrode 1 made of TO (indium tin oxide) or the like
2, an alignment film 13 made of polyimide, polyvinyl alcohol, or the like is applied and formed on the entire surface of the transparent electrode 12, and a rubbing process is performed in a predetermined direction, for example, a horizontal direction in the drawing.

On the other hand, on the inner surface of the rear substrate 20, a first electrode portion 21 made of Ta or the like formed integrally with a wiring layer (not shown) and Ta ₂ O formed by anodization are used.
₅ and a second electrode layer 23 made of Cr or the like.
A metal) element is formed, and a reflective electrode 24 is formed on the second electrode layer 23 by depositing a metal such as Al by vapor deposition or sputtering.

On the surface of the reflective electrode 24, a photoresponsive film 25 made of a photochromic material is formed. This photoresponsive film 25 is obtained by doping Fe into PLZT. PLZT is ((Pb, La) (Z
r, Ti) O ₃ ) is a translucent ceramic having a structure, and is known to exhibit positive photochromism that is colored black when irradiated with light having a wavelength of 3200 to 5100 °.

As the photoresponsive film 25, a film exhibiting positive photochromism can be used. In particular, a film exhibiting a deep color developing characteristic and a film having a high coloring speed and fading speed are preferable. It is preferable to use one that has little deterioration and high durability even when used over a period. Also,
When the light irradiation amount is large, it is necessary to make the color darker, but it is particularly preferable to make the color black. Furthermore, not only a material that becomes transparent when the light irradiation amount is small, but also a material that only makes the color lighter or lighter, for example, a material that whitens, can be used.

Examples of such a material include spirooxazines as an organic photochromic compound. Also, spiropyrans, spironaphthoxazines,
Compounds such as spirothiopyrans, chromenes, dichromenes, fluorans, triphenylmethanes, fluorones, fulgides, diarylethenes, azobenzene, diarylethene, triarylmethane, and indigo can also be used. Organic photochromic compounds include those represented by the general formula shown in Chemical Formula 1, and specific examples thereof include 1'-butyl-
3 ', 3'-dimethyl-6-nitro-spiroindolinobenzopyran, 1'-butyl-3', 3'-
Dimethyl-spiroindolinonaphthoxazine, 1′-propyl-6-nitro-spirobenzothiazolinobenzopyran shown in Chemical formula 4, spirodibenzopyran shown in Chemical formula 5,
2,2-adamantylidenechromene shown in Chemical formula 6, 1'-propyl-3 ', 3'-dimethyl-5'6-
Dinitro-spiroindolinobenzothiopyran, fluorane shown in Chemical formula 8, 1,1,1-tris (4-
(N, N-dimethylphenyl) ethanenitrile and the like. In Chemical Formula 1, R1, R2, and R3 are alkyl groups having 1 to 10 carbon atoms, and R4 and R5 represent various substituents.

[0022]

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[0023]

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[0024]

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[0025]

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[0026]

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[0027]

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[0028]

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[0029]

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[0030]

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These various materials exhibiting photochromism can be dispersed in a dispersion medium composed of various transparent inorganic and organic materials. For example, they are dispersed in a metal alkoxide or other alkoxide solution or a mercaptide solution and dried. , Baked or used as polyvinyl butyral resin, polyvinyl alcohol resin, acrylic resin, ethyl cellulose, unsaturated polycarboxylic acid, phosphate ester activator, polyester resin, silane coupling agent, titanium coupling agent, aluminum coupling agent, etc. They may be dispersed. Alternatively, the photoresponsive film may be formed using a copolymer of various materials exhibiting photochromism and a monomer. Further, a compound in which a photochromic compound is dispersed in a polymer liquid crystal may be used, and a compound in which a photochromic compound is covalently bonded to a polymer liquid crystal,
For example, a copolymer of a liquid crystal and a photochromic compound can be used. The ratio of the additive such as a dispersant in various materials containing these photochromic compounds varies depending on the material, but is about 3 to 50 wt%.

As a method of forming a film using the above-mentioned materials, a method of applying a mixed solution of an alkoxysilane and a photochromic compound, and hydrolyzing the alkoxysilane to form a film, and a method of applying a mixed solution of an alkoxysilane and a photochromic compound are applied. A method of forming a silica glass by adding a photochromic compound and dehydrating and condensing by adding a photochromic compound when hydrolyzing, applying an organic resin containing the photochromic compound, heating, drying, and curing by another method, a photochromic compound. There is a method of bonding a film made of an organic resin to be contained.

On the surface of the photoresponsive film 25, an alignment film 26 similar to that described above is formed, and a rubbing process is performed in the direction corresponding to the alignment direction and the twist angle of the liquid crystal molecules in the liquid crystal layer 30 as described above. Will be applied.

In this embodiment, an active matrix type liquid crystal device using MIM elements is used. However, another active element such as a TFT may be used, or a simple matrix type liquid crystal device may be used.

As the liquid crystal layer 30 of the present embodiment, what is called polymer dispersed liquid crystal is used. In this case, liquid crystal molecules and polymers are present in the liquid crystal layer 30 in a state of being dispersed with each other. This state includes a state in which polymer particles are dispersed in a liquid crystal, a state in which a large amount of polymer particles are arranged in a liquid crystal so as to be connected, and a state in a mesh-like skeleton of a gel polymer. There are various modes such as those containing liquid crystal.

In this case, a solution in which a liquid crystal and a polymer precursor that can be polymerized by light or an electron beam are compatible is injected into an empty cell, and then irradiated with light or an electron beam. It is preferable to form the liquid crystal layer 30 by polymerizing the polymer precursor and precipitating the polymer in the liquid crystal by phase separation. Various liquid crystals can be used as long as they have dielectric anisotropy and refractive index anisotropy. Here, when the liquid crystal has a positive dielectric anisotropy, the liquid crystal is horizontally aligned by rubbing the substrate surface, and when the liquid crystal has a negative dielectric anisotropy, the liquid crystal is vertically aligned. Is preferred. In particular, when a liquid crystal layer is formed by this method, both the liquid crystal and the polymer can be oriented in a predetermined direction.

Examples of the polymer precursor include photo- or electron-beam-polymerizable compounds such as biphenyl methacrylate and other methacrylates, acrylates and other vinyl compounds.
A thermopolymerizable compound such as an epoxy compound can be used. The thermopolymerizable compound can be heated to an appropriate temperature to cause phase separation of the polymer. In addition, a thermoplastic compound such as ethyl cellulose can be used as the polymer. In this case, the polymer is mixed with the liquid crystal in a heated state, and then injected into an empty cell and cooled to cause phase separation of the polymer. be able to. Note that by mixing a chiral component into the liquid crystal component, display contrast and viewing angle dependency can be improved.

As a specific example of forming the polymer-dispersed liquid crystal layer 30 in this embodiment, for example, 90 wt% of “BL007” (trade name) manufactured by Merck Ltd. is used as the liquid crystal.
0.1 to 3 wt% of Merck's “CB15” (trade name) (provided that it is not limited to the above range depending on the twist angle) as a chiral component, and 7 wt% of biphenyl methacrylate as a polymer precursor. % Of the solution, and the solution is injected into an empty cell having a gap between the front substrate 10, the rear substrate 20, and the sealing material of about 5 μm and sealed. Irradiation causes the polymer particles to phase separate in the liquid crystal. When the irradiation amount of the ultraviolet rays is appropriately set, the driving voltage becomes about 5 volts, and the clock IC can be driven sufficiently. In such a method of forming a liquid crystal layer, the ratio of the liquid crystal component is 50 to 95.
By being about wt%, the drive voltage and the display mode can be set in a practical range.

In such a liquid crystal layer 30, when no electric field is applied, both the liquid crystal and the polymer particles in the liquid crystal layer are horizontally aligned, and the liquid crystal and the polymer particles have substantially the same optical refractive index. It becomes a light transmitting state. On the other hand, when an electric field exceeding a predetermined threshold is applied, the liquid crystal having dielectric anisotropy is vertically aligned in a region where the electric field is applied, and the liquid crystal also has refractive index anisotropy. A difference occurs between the refractive index of the polymer and the polymer, which results in a light scattering state.

For this reason, by applying a voltage exceeding the threshold value to an area corresponding to the display contents such as numbers, characters, figures, etc., it is possible to make the area opaque. In this case, the liquid crystal layer 3
In order to apply a predetermined electric field to zero, a large number of electrodes in a matrix may be formed on the inner surfaces of the front substrate 10 and the rear substrate 20, or some of the numerals, characters and figures may be formed. When it is sufficient to display only a limited number of display contents, some segment electrodes may be formed on one substrate inner surface, and a common electrode may be formed on the other substrate inner surface. Further, by setting the refractive indexes of the liquid crystal and the polymer, it is also possible to adopt a configuration in which a light scattering state occurs when no electric field is applied and a light transmitting state occurs when an electric field is applied.

In this embodiment, when the liquid crystal layer 30 is in the light transmitting state, the external light passes through the liquid layer 30 as it is and reaches the light responsive film 25.
5 is colored by absorbing light, and in particular, is colored black in the case of the material of the above embodiment. Therefore, the display is black, and the contrast is higher than that of a conventional black display relying only on the regular reflection of the reflective electrode 24, and the display is black which is easily visible. On the other hand, when the liquid crystal layer 30 is in the light scattering state, the external light is scattered by the liquid crystal layer 30, so that the external light hardly reaches the inside of the liquid crystal layer 30, and the light-responsive film It becomes more difficult for light to reach 25. Therefore, the light-responsive layer remains transparent, and the whiteness due to light scattering of the liquid crystal layer 30 does not decrease. Therefore, in the present embodiment, the display contrast ratio can be increased as compared with a conventional reflection type liquid crystal device using a polymer-dispersed liquid crystal layer, and at the same time, the glare in the light transmission state and the reflection of the background are reduced or Can be prevented.

The description of the black and white display mode is as follows.
This relates to a case where the liquid crystal layers 30 in all the dot regions are in a light transmitting state or a light scattering state in a pixel region including each of the red, green, and blue dot regions, or a case where the color filter 11 is not present. In practice, due to the presence of the color filter 11, the dot area in each pixel area becomes dark when the liquid crystal layer is in a light transmitting state, and becomes bright when the liquid crystal layer is in a light scattering state. Therefore, when the light transmittance of the liquid crystal layer increases, the light responsive film 25 becomes darker or the light transmittance lowers (or becomes black), so that the display mode further darkens or darkens, and light scattering of the liquid crystal layer causes light scattering. When the light transmittance of the liquid crystal layer decreases, the light responsive film 25
Is lightened or the light transmittance is increased (or becomes transparent), so that the display mode is lightened or brightened.

FIG. 2 shows the structure of a reflection type liquid crystal device according to another embodiment of the present invention. In this embodiment, the same parts as those in the previous embodiment are denoted by the same reference numerals, and description thereof will be omitted. In the present embodiment, photoresponsive fine particles 27 in which the same photochromic compound as described above is formed in the form of fine particles are dispersed in the liquid crystal layer 30, and black color display is realized by coloring the photoresponsive fine particles 27, and white display is achieved by fading. So as not to affect The photoresponsive fine particles 27 are scattered in a gap material spraying step together with a minute gap material 28 made of a transparent resin for defining an inter-substrate gap between the front substrate 10 and the rear substrate 20. It is preferable that a solution that is compatible with the polymer precursor is injected into the gap, the polymer precursor is precipitated by polymerization, and the polymer is dispersed in the liquid crystal. According to this method, the photoresponsive fine particles 2 can be formed together with the gap material 28 without any modification to the conventional process.
7 can be manufactured simply by spraying on one substrate.

As the photoresponsive fine particles, in addition to the photochromic compound in the form of fine particles as it is, the above-mentioned dispersion medium and various binding substances mixed or bound to the photochromic compound, or a transparent substance added to the photochromic compound. A coated material can be used.

Also in this embodiment, when the liquid crystal layer 30 is in the light transmitting state, the light-responsive fine particles 27 are irradiated with external light, so that the light-responsive fine particles 27 are colored to improve the contrast of black display. . When the liquid crystal layer 30 is in the light scattering state, external light hardly reaches the photoresponsive fine particles 27, so that the photoresponsive fine particles 27 are not colored and do not hinder white display.

Also in this embodiment, the photoresponsive fine particles 2
As 7, it is preferable to have light response characteristics similar to the characteristics of the material of the light-responsive film 25 described in the above embodiment, that is, color change characteristics, color change speed, durability, and the like. Further, the approximate particle size (outer diameter) of the light-responsive fine particles 27 must be smaller than the thickness d of the liquid crystal layer 30.
It is preferably about 5 to 60% of the thickness d. This is because, when the grain size is close to the thickness d, the liquid crystal layer 30 easily receives color from the outside even when the liquid crystal layer 30 is in a light scattering state, and the color is easily formed.

In the above-described embodiment, an example is shown in which the photoresponsive fine particles 27 are dispersed and arranged in the liquid crystal layer 30. However, the photoresponsive fine particles 27 are dispersed on the alignment film 26 of the rear substrate 20 to be aligned. By assembling the liquid crystal cell with the photoresponsive fine particles 27 adsorbed on the film 26, the photoresponsive fine particles 27
Can be unevenly distributed on the inner surface of the rear substrate 20 in the liquid crystal layer 30. As described above, by distributing the liquid crystal layer 30 so as to be biased toward the rear substrate 20,
In the light scattering state of the liquid crystal layer 30, it is possible to make it difficult for external light to reach the light-responsive fine particles 27. Therefore, by preventing coloring of the light-responsive fine particles 27 and securing the whiteness of white display, the display quality is improved. The contrast ratio can be further increased.

Further, by selecting the material, the light-responsive fine particles 27 are formed to be heavier than the average specific gravity of the liquid crystal layer 30,
The photoresponsive fine particles 27 are mixed into a solution in which a liquid crystal and a polymer precursor are compatible or a liquid crystal and a polymer dispersoid, and injected into a liquid crystal cell. And the light-responsive fine particles 27 settle down in the liquid crystal layer 30,
The photoresponsive fine particles 27 may be biased toward the rear substrate 20 by being adsorbed on the alignment film 26 formed on the inner surface of the rear substrate 20.

In each of the above embodiments, the case where an active matrix type liquid crystal display device is constituted has been described as an example. However, the present invention is not intended to have an active element if it is a polymer dispersion type reflection type liquid crystal device. It may be a liquid crystal display device, or may be configured as an electro-optical element used for purposes other than display.

FIG. 3 shows an electronic apparatus equipped with a reflective liquid crystal device. 3A shows an example in which a reflection type liquid crystal device is mounted on a portable telephone, FIG. 3B shows an example in which a liquid crystal device is mounted on a watch, and FIG. 3C shows an example in which a liquid crystal device is mounted on a personal computer. . By mounting a reflective liquid crystal device and low power consumption liquid crystal device in this way,
Electronic devices with low power consumption can be obtained.

[0051]

As described above, according to the present invention, by disposing the photoresponsive substance, when the light transmittance of the liquid crystal layer increases, the appearance on the reflection surface becomes darker, and the light transmission of the liquid crystal layer increases. When the ratio is low, the appearance on the reflecting surface is configured to be lighter, so that when the light transmittance of the liquid crystal layer is higher and the display mode by the liquid crystal layer is darker, the color tone becomes darker and light scattering is performed. When the light transmittance becomes low and the display mode becomes lighter, the lightness or brightness of the display is prevented from being hindered, so that the display contrast by the liquid crystal layer can be improved. Also, when the light transmittance of the liquid crystal layer increases, the dazzling and background reflection due to the reflection surface are reduced by the dark-colored photoresponsive substance,
Visibility can be further improved.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing the structure of an embodiment of a reflection type liquid crystal device according to the present invention.

FIG. 2 is a schematic sectional view showing the structure of another embodiment of the reflection type liquid crystal device according to the present invention.

FIG. 3 is a diagram illustrating an electronic apparatus equipped with a reflective liquid crystal device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Front-side substrate 11 Color filter 12 Transparent electrode 13 Alignment film 20 Back-side substrate 21 1st electrode part 22 Insulating film 23 Second electrode layer 24 Reflection electrode 25 Photoresponsive film 26 Alignment film 27 Photoresponsive fine particles 28 Spacer 30 Liquid crystal layer

Claims (6)

[Claims] 1. A liquid crystal layer of a polymer dispersion type in which a liquid crystal and a polymer are mutually dispersed is disposed between two substrates, and the degree of light scattering of the liquid crystal layer is controlled by an electric field applied to the liquid crystal layer. In a reflective liquid crystal device having a reflective surface on the back side of the liquid crystal layer, a state in which the light transmittance of the liquid crystal layer is high inside the liquid crystal layer or between the liquid crystal layer and the reflective surface In the reflection type liquid crystal device, a light-responsive substance which becomes darker and becomes lighter or has a higher light transmittance when the light transmittance of the liquid crystal layer is low due to light scattering is arranged. 2. The reflective liquid crystal device according to claim 1, wherein the photoresponsive substance is formed of a photochromic material that turns black as the light irradiation amount increases. 3. The reflection type liquid crystal device according to claim 1, wherein the photoresponsive substance is formed on the reflection surface. 4. The reflection type liquid crystal device according to claim 1, wherein the photoresponsive substance is dispersed in the liquid crystal layer. 5. The reflection type liquid crystal device according to claim 4, wherein the photoresponsive substance is arranged in the liquid crystal layer so as to be biased toward the rear substrate. 6. A polymer-dispersed liquid crystal layer in which a liquid crystal and a polymer are mutually dispersed is disposed between two substrates, and the liquid crystal layer is at least in a light transmitting state and a light transmitting state depending on an electric field applied to the liquid crystal layer. A reflection type liquid crystal device in which a scattering state is controlled and a reflection surface is provided on the back side of the liquid crystal layer, wherein the liquid crystal layer is provided inside the liquid crystal layer or between the liquid crystal layer and the reflection surface. An electronic device equipped with a reflective liquid crystal device in which a light-responsive substance is disposed which becomes darker when light is in a light transmitting state and becomes lighter when the liquid crystal layer is in a light scattering state or has a higher light transmittance. .