JPH07333606A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To improve bright visibility by making more external light incident on a liquid crystal panel and returning the more reflected light from this liquid crystal panel toward a user. CONSTITUTION:This liquid crystal display device has a light transmission plate 4 made of an acrylic resin on a liquid crystal cell 1. The angle 5 formed by the plane of this light transmission plate 4 and a horizontal plane is set at 30 deg.. A light scatterable structure 12 exists on the front surface on the upper side of the light transmission plate 4. The light transmission plate 4 is provided with a microprism 13 on its lower side. The incident light 10 which is emitted from the lower side of the light transmission plate 4 and is made incident on the liquid crystal cell 1 is refracted and propagated toward the liquid crystal cell 1. The incident light 10 which is emitted from the lower side of the light transmission plate 4 and is made incident on the liquid crystal cell 1 is reflected by a reflection plate 7 existing on the rear side of the liquid crystal cell 1 clamped by two sheets of polarizing plates 6. The reflection surface thereof consists of many fine surfaces inclined upward with respect to the surface of the liquid crystal cell 1. The incident light from above propagates in a direction nearly perpendicular to the surface of the liquid crystal cell 1 and arrives at the user's eyes without falling downward.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device having good visibility. In particular, the present invention relates to a liquid crystal display device that is used while leaning against it like a laptop or notebook personal computer.

[0002]

2. Description of the Related Art Liquid crystal display devices used in conventional laptop and notebook personal computers are of a transmissive type having a backlight on the back surface of a liquid crystal panel and a reflective type having a light reflecting plate on the back surface of the liquid crystal panel. There are two types, but the transmissive type has a problem that the power consumption of the battery is large, and the reflective type has a problem that it is dark and difficult to see, and it is impossible to achieve both visibility and long life of the battery.

When the cause of the reflection type that is dark and difficult to see is analyzed, it can be understood that the cause is mainly that the outside light does not reach the eyes of the user (observer), and the utilization efficiency of light is low. That is, only a small amount of the external light incident on the liquid crystal panel returns to the direction of the user's eyes. In particular, in a liquid crystal display device that is used by leaning against it like a laptop or notebook personal computer, in an environment where the incident light from above is particularly strong like in a normal office, most of the incident light is reflected on the back surface of the liquid crystal panel. It is reflected downward by the installed light reflection plate and looks very dark to the user.

In order to solve this, in EP0490132A2, a multi-faceted reflector having an angle with respect to the display device surface is used. A method is proposed in which light that is obliquely incident is propagated in the direction of the user to be brightened. Further, Japanese Patent Laid-Open No. 63-30825 proposes a method of obtaining the same effect by using a reflecting plate having a groove having a saw-shaped cross section. However, even with this method, the improvement in brightness is not so high as about 1.4 times, and it has not been widely spread.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to make more external light incident on a liquid crystal panel and to return more reflected light from the liquid crystal panel to the user, which is bright and has good visibility. An object is to provide a liquid crystal display device. Furthermore, the purpose is to extend the life of the battery.

[0006]

In order to achieve the above object, the present invention uses the following means.

(Means 1) A pair of substrates, at least one of which is transparent, electrodes provided on the substrates, a liquid crystal composition layer sandwiched between the substrates, and light depending on the alignment state of liquid crystal molecules of the liquid crystal composition layer. In a liquid crystal display device including a liquid crystal cell having a polarizing unit that changes the transmission or reflection characteristics of the liquid crystal and a driving unit that drives the liquid crystal layer, a light guide plate is provided on the upper surface of the liquid crystal cell, and the light guide plate is incident. A liquid crystal display device having a structure for guiding the light that is generated to the surface of the liquid crystal cell.

(Means 2) A pair of substrates, at least one of which is transparent, electrodes provided on the substrates, a liquid crystal composition layer sandwiched between the substrates, and light depending on the alignment state of liquid crystal molecules of the liquid crystal composition layer. In a liquid crystal display device comprising a liquid crystal cell having a polarizing means for changing the transmission or reflection characteristics of the liquid crystal, and a driving means for driving the liquid crystal layer, an angle between the surface of the liquid crystal cell and a horizontal plane is 45 degrees or more, A light guide plate is provided on an upper surface of the liquid crystal cell, an angle formed by a surface of the light guide plate and a horizontal plane is less than 45 degrees, and light incident on the light guide plate is guided to a surface of the liquid crystal cell. Liquid crystal display device characterized by.

(Means 3) The liquid crystal display device according to means 1, wherein a micro prism is provided on the lower surface of the light guide plate.

Means 1 to 3 are for solving the basic problem of the present invention of allowing more external light to enter the liquid crystal panel.

(Means 4) A reflecting plate is provided below the liquid crystal cell, and the reflecting plate transmits light propagating through the light guide plate and incident on the surface of the liquid crystal cell mainly to the surface of the liquid crystal cell. 2. The liquid crystal display device according to means 1, wherein the liquid crystal display device reflects in different directions.

The means 4 is for returning the light path of the reflection plate to the direction of the eyes of the user to make it brighter.

(Means 5) A liquid crystal display device according to means 4, wherein a transparent medium is filled between the liquid crystal cell and the reflection plate.

According to the means 5, the loss of light at the interface with the air layer on the lower surface of the liquid crystal cell can be remarkably suppressed.

(Means 6) A liquid crystal display device according to means 5, wherein any one of the surface of the light guide plate and the surface of the reflection plate is provided with a light scattering property.

(Means 7) The means for polarizing according to claim 6, wherein the polarizing means is a polarizing plate provided on the surface of the liquid crystal cell, and the interface of the polarizing plate with air is flat and has no light scattering property. Liquid crystal display device.

(Means 8) A liquid crystal display device according to means 6, wherein the local surface structure of the reflector is a mirror surface structure.

(Means 9) The upper surface and the lower surface of the light guide plate, the surface of the reflection plate, and any surface of the interface of the polarizing plate with the air are locally flat and light transmissive, and A means 5 characterized in that light-scattering property is imparted to the reflector.
The liquid crystal display device according to item 1.

The means 6 to 9 have a problem that it is difficult to improve the brightness, which is difficult in the prior art, and the shape of the light source (for example, a fluorescent lamp on the ceiling) is visually difficult to see when the liquid crystal display is used, depending on the usage environment of the display. It is to achieve both prevention and

(Means 10) The liquid crystal cell is provided with two or more kinds of color filters having different colors, the colors are different, and there is a light transmissive region between the adjacent color filters and between the substrates. 2. The liquid crystal display device according to means 1.

(Means 11) The liquid crystal display device according to means 10, wherein both of the two or more kinds of color filters having different colors and the light transmissive region are stripe-shaped.

(Means 12) The means 1 is characterized in that the area ratio of the region without the color filter is 20% or more.
The liquid crystal display device according to 0 or 11.

(Means 13) A liquid crystal display device according to means 11, wherein both the stripe-shaped color filter and the light-transmissive region are substantially parallel to a horizontal plane.

The means 10 to 13 provide a brighter color display.

(Means 14) The liquid crystal display device according to any one of means 1 to 11 to 13, wherein the liquid crystal composition layer and the polarizing means are arranged so as to have normally open characteristics. .

According to the means 14, the amount of light introduced especially from the non-electrode portion can be remarkably increased, and a brighter display can be obtained.

(Means 15) The liquid crystal display device according to means 1, wherein the liquid crystal cell and the light guide plate are connected in a semi-fixed state, and an angle formed by the liquid crystal cell and the light guide plate can be adjusted.

The means 15 makes it possible to optimize the brightness according to the environment in which the display device is used.

(Means 16) A liquid crystal display device according to means 15, characterized in that the liquid crystal cell and the light guide plate are folded so that their surfaces are parallel to each other and can be integrated.

The means 16 further expands the function of the means 15,
This is for enhancing portability. (Means 17) A pair of substrates, at least one of which is transparent, electrodes provided on the substrates, a liquid crystal composition layer sandwiched between the substrates, light transmission or light transmission depending on the alignment state of liquid crystal molecules of the liquid crystal composition layer. In a liquid crystal display device comprising a liquid crystal cell having a polarizing means for changing a reflection characteristic and a driving means for driving the liquid crystal layer, a light guide plate is provided on an upper surface of the liquid crystal cell, and a light source is further provided on the light guide plate. And a structure for guiding the light incident on the light source system to the surface of the liquid crystal cell when the light source is not lit, and when the light source is lit, the light guide plate of the light guide plate A liquid crystal display device having a structure in which light from the light source is guided to the surface of the liquid crystal cell by placing the light source system on an upper surface.

(Means 18) The liquid crystal display device according to means 17, further comprising a switch for automatically turning on the light source by placing a light reflecting plate on the upper surface of the light guide plate.

According to the means 17 and 18, the visibility can be secured even when the display device of the present invention is used in a dark environment.
Moreover, since the light source can be turned off in a bright environment, the life of the battery can be further extended.

[0033]

First, the principle of improving the light utilization efficiency, which is the first operation of the present invention, will be described. Most of the light sources in a normal office are installed on the ceiling. Therefore, a laptop personal computer (P
Most of the light emitted to office equipment such as C) and a notebook PC propagates from the upper side to the lower side. However, conventional display devices of laptop PCs and notebook PCs are leaning against each other, and the energy of the light per unit area irradiated on the display surface is the same as that of a desktop computer used with the display device plane facing directly above. It is significantly smaller than the case.
Furthermore, due to the characteristics of the reflector used, most of the light emitted from above is reflected downward, and the intensity of light transmitted through the panel corresponding to the brightness of the liquid crystal display device and transmitted to the eyes of the user is even lower. And only a very dark display can be obtained. Therefore, although the life of the battery is remarkably reduced, the transmissive type having a backlight is inevitably used.

According to the present invention, the path of light from such a general office light source can be controlled, and the intensity of light reaching the eyes of the user, that is, the brightness of the display device is improved. It is possible. First, a flat transparent body (referred to as a light guide plate in the present invention) is set on the upper surface of the liquid crystal panel, and the light emitted from above the office is taken in by the light guide plate and then the light is guided to the liquid crystal panel. In order to take in more light from above the office into the light guide plate, it is advisable to set the light guide plate surface to 45 degrees or less with respect to the horizontal plane. In addition, in order to guide more light emitted from the lower surface of the light guide plate to the liquid crystal panel, it is preferable to provide the lower surface of the light guide plate with a structure having a refraction effect such as a micro prism. In this way, stronger light is incident on the liquid crystal panel. In order to make it even brighter, considering that the light that has propagated through the light guide plate is incident on the panel surface from slightly above, a light reflector with asymmetrical reflection characteristics allows the light to almost reach the liquid crystal cell surface. The light is reflected in the vertical direction, that is, in the direction of the user's eyes. As the reflecting plate, for example, a fine reflecting mirror inclined slightly upward may be used.

The present invention also provides means for solving the following problems which cannot be solved by simply guiding the outside light. That is, although the light use efficiency can be remarkably improved as described above, if both the light guide plate and the reflection plate are composed of only flat surfaces in order to suppress the loss of light, the light source (for example, a fluorescent lamp on the ceiling) of This is a problem that the shape is visually recognized and becomes difficult to see. Therefore, as shown in means 6, if at least one surface is introduced in the optical path from the entrance surface of the light guide plate to the exit surface of the liquid crystal panel, the shape of the light source becomes invisible and the brightness of the display surface is reduced. Becomes uniform and becomes easy to see. It should be noted that such a surface that disturbs the optical path suffices if there is only one point in the propagation path of the light from the external light source to the eyes of the user. Rather, as shown in the means 7 and the means 8, it is possible to improve the light utilization efficiency as a whole by using a flat surface in other portions.

Next, based on the first effect of improving the light utilization efficiency of the present invention, the second effect of colorization will be described.

If the utilization efficiency of external light is dramatically improved,
Even if light is absorbed by the color filter, reflective color display is possible. To take in as much light as possible, the cell structure should be a light-transmissive region, except for the light-shielding layer between adjacent color filters provided in a normal transmissive type. good. As a liquid crystal display mode, a normally open type in which the voltage is zero and the non-electrode portion has a high light transmittance is desirable. It is desirable that the area of the region between the adjacent color filters for introducing light is made high to some extent, and the ratio thereof is preferably 20% or more.

In addition to the first action and the second action, the light path can be optimized by adjusting the light guide plate arrangement by means of the means 15 according to the office environment. That is, it can be made brighter by adjusting according to the relative position between the light source installed on the ceiling and the display device. According to the means 16, the light guide plate can be folded and stored when the display device is not used,
Saves storage space. Means 17 and 18 show a method for utilizing the auxiliary light source when the display device use environment is extremely dark.

[0039]

EXAMPLES The present invention will be described in detail below with reference to examples.

Example 1 Two transparent glass substrates were used as substrates. Each of them has a thickness of 1.1 mm and its surface is optically polished. An XY matrix transparent electrode connected to the driver IC is formed inside the substrate.
It comprises 80 pixels. The panel size is 9.4 inches diagonally. Nematic liquid crystal ZLI between these substrates
2293 (manufactured by Merck & Co.), S-811
A liquid crystal composition containing a small amount of (manufactured by Merck) was sandwiched. The composition has a natural pitch of 10.5 μm and a gap between the substrates of 6.1 μm. A polyimide-based alignment film LQ-1800 (manufactured by Hitachi Chemical Co., Ltd.) is applied on the electrodes by a spin coating method to a thickness of about 500Å. The liquid crystal material is surface-treated by the rubbing method, so that the liquid crystal material has a tilt angle of 5 degrees (pretilt) and a twist angle of 240 degrees. Diameter 6.
A 3 μm bead spacer (made of divinylbenzene) acts to maintain a constant gap of 6.1 μm. A polarizing plate (NPF-F1225DU manufactured by Nitto Denko Corporation) and a retardation plate were arranged as shown in FIG. 7 to obtain normally open characteristics as shown in FIG. Note that the normally open state increases the transmittance when light is incident in an oblique direction, and achieves the first effect of the present invention, that is, improvement of light utilization efficiency.

FIG. 1 shows the appearance of the liquid crystal display device of this embodiment.
FIG. 2 shows a side sectional view of the light guide plate 4 provided on the upper surface of the liquid crystal cell, and FIG. 3 shows a side sectional view of the reflection plate 7.

In this embodiment, the angle 3 formed by the liquid crystal cell surface and the horizontal surface is set to 60 degrees. An acrylic resin light guide plate 4 was provided on the upper surface of the liquid crystal cell 1, and the angle 5 formed by the plane of this light guide plate and the horizontal plane was 30 degrees. Further, as shown in FIG. 2, a light-scattering structure 12 is provided on the upper surface of the light guide plate, and a micro prism 13 is provided on the lower side of the light guide plate. The light 10 is refracted and propagates in the direction of the liquid crystal cell. Although the light-scattering structure 12 is a fine concavo-convex structure in this embodiment, it is not limited to this as long as it has a light-scattering property. For example,
A flat plate-like structure having a fine refractive index distribution may be used.
The incident light 10 to the liquid crystal cell emitted from below the light guide plate is
The light is reflected by the reflection plate 7 on the back side of the liquid crystal cell 1 held by the two polarizing plates 6. As shown in FIG. 3, this reflecting surface is composed of a large number of fine surfaces that are inclined upward with respect to the liquid crystal cell surface, and the light incident from above does not fall downward unlike the conventional reflecting plate, and the liquid crystal cell It propagates in a direction almost perpendicular to the plane and reaches the eyes of the user. Silicon oil, which is a transparent medium, is filled between the reflector and the liquid crystal cell. The surface of the polarizing plate is flat and not subjected to non-glare treatment.

The liquid crystal display device of this example was installed and observed just below a fluorescent lamp in an office having a fluorescent lamp on the ceiling. The vertical illuminance at the location where the liquid crystal display device is installed is 800 lx. Drive is 1/240 duty, 1
Time-division driving was performed with a bias of / 13. As a result, when the brightness of the liquid crystal cell surface was measured with a luminance meter in the vertical direction of the liquid crystal cell, it was 52 cd / mm ² in a bright display state, and a sufficiently bright and easy-to-see display was obtained without a light source.

(Comparative Example) In Example 1, the light guide plate 4 on the upper surface of the liquid crystal cell 1 was removed, and the reflection plate 7 was also replaced with a conventional type having omnidirectional and symmetrical characteristics. In a similar office with a fluorescent lamp on the ceiling, it was installed just below the fluorescent lamp and observed. As a result, the brightness obtained in the bright display state was only 7 cd / mm ² , which was dark and difficult to see as compared with the transmissive type having a backlight.

(Embodiment 2) In Embodiment 1, the upper surface of the light guide plate 4 is flattened to eliminate the light-scattering property. Instead, the surface of the micro prism 13 provided on the lower surface has unevenness having the light-scattering property. Given the structure. Others are the same as in the first embodiment. When the same observation as in Example 1 was performed, it was 41 cd / mm ² in the bright display state, and it was bright without a light source, and an easy-to-see display in which the shape of the ceiling light source was not visible was obtained.

Example 3 In Example 1, the upper surface of the light guide plate 4 was flattened to eliminate the light scattering property, and instead the surface of the reflection plate was roughened to provide the light diffusion property. Others are the same as in the first embodiment. When the same observation as in Examples 1 and 2 was performed, it was 34 cd / mm ² in the bright display state, and a bright and easy-to-see display was obtained without a light source for the liquid crystal cell.

In this embodiment, a reflector having an asymmetrical reflection characteristic is used as a more desirable structure. However, even if a reflector having a conventional symmetrical characteristic and a slight diffusion characteristic is used, it is better than that of the comparative example. A bright 18 cd / mm ² was obtained.

(Embodiment 4) In this embodiment, a color filter as shown in FIGS. 4 and 5 is provided in addition to the structure of the first embodiment. Unlike the color filters used in general transmissive liquid crystal display devices, the three primary colors (here,
There is no light-shielding layer between the plurality of color filters 15a, 15b, 15c indicating red (R), green (G), and blue (B). The three primary colors may be cyan (C), magenta (M), and yellow (Y). Further, in the present embodiment, not only the light shielding layer is removed, but also a more desirable configuration is 15a, 1
A transparent gap is formed between 5b and 15c, from which light 1
I made 9 more invasion. Even when covered with one or two of the above-mentioned color filters instead of the transparent gap, there is an effect of taking in external light, and therefore there is an effect of improving the light utilization efficiency. The width of each stripe-shaped color filter layer is 60 μm (area ratio 60%), and the width of the transparent gap between the color filters is 40 μm (area ratio 40%).

Compared to the case without a color filter as in Example 1, the light utilization efficiency is about 1/3 in the area where the area ratio of the color filter layer is 60%, and therefore the total light utilization efficiency is about 1/3. 60% (0.6 / 3 + 0.4), 52
A brightness of about × 0.6 = 31 cd / mm ² can be obtained, and a display device having sufficient brightness can be obtained without a backlight.

(Embodiment 5) This embodiment is the same as Embodiment 4 except for the following constitution. The vertical electrodes form common electrodes, the number of which is 320, the horizontal electrodes form segment electrodes, the number of which is 480 × 3 (RGB), and the number of pixels is 320 × (480 × 3). . The common electrode is divided into left and right and is driven at 1/160 duty.

When both the color filter and the transparent area are made parallel to the horizontal plane (direction perpendicular to the paper surface in FIG. 8), most of the incident light 10 to the liquid crystal cell is reflected by the reflecting plate as shown in FIG. In the return path after the above, the light passes through the color filter 15 and reaches the eyes of the user of the display device, and the contrast is improved.

(Sixth Embodiment) In this embodiment, a light source system 22 is additionally provided in addition to the structure of the first embodiment.

As shown in FIG. 9, this light source system is made of a transparent body, and the light source 21 is internally provided at its side end portion. At the same time, it has a property of reflecting the light from the light source on the upper surface of the transparent body and transmitting it on the lower surface, and guiding it to the light guide plate 4. By installing the light source system 22 on the light guide plate 4, the light source 21 is automatically turned on by the action of the switch 23. In a normal brightness environment, outside light is guided to the surface of the liquid crystal cell without the light source system 22, and the light source is used only in a very dark environment. This saves battery.

[0054]

According to the liquid crystal display device of the present invention, more external light is made incident on the liquid crystal panel, and more reflected light from the liquid crystal panel is returned to the direction of the user, so that it is bright and has good visibility. A liquid crystal display device can be provided.

Furthermore, the life of the battery can be extended.

[Brief description of drawings]

FIG. 1 is an external view of a liquid crystal display device of the present invention schematically shown.

FIG. 2 is an enlarged side sectional view of a light guide plate provided on the upper surface of a liquid crystal cell.

FIG. 3 is an enlarged side sectional view of a reflection plate.

FIG. 4 is a schematic front view of a liquid crystal panel of an example including a color filter.

FIG. 5 is a schematic side view of a liquid crystal panel of an example including a color filter.

FIG. 6 is a characteristic diagram showing a relationship between applied voltage and brightness of a normally open type liquid crystal element.

FIG. 7 is a configuration diagram of a no-lima open type liquid crystal element.

FIG. 8 is a schematic side view of another embodiment including a color filter.

FIG. 9 is an external view of a liquid crystal display device of the present invention having an auxiliary light source.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Liquid crystal cell, 2 ... Driving means, 3 ... Angle which a surface of a liquid crystal cell and a horizontal surface make, 4 ... Light guide plate (flat transparent body), 5 ... Angle which a surface of a light guide plate and a horizontal surface make, 6 ... Polarizing plate , 6a ... First polarizing plate, 6b ... Second polarizing plate, 7 ... Reflecting plate, 7a ... Transparent medium, 8 ... Connection part between liquid crystal cell and light guide plate, 9 ... Ambient light, 10 ...
Light incident on the liquid crystal cell, 11 ... Light emitted from the liquid crystal cell, 1
2 ... Light scattering structure, 13 ... Micro prism, 14 ... Reflected light, 15 ... Color filter, 15a ... First color filter, 15b ... Second color filter, 15
c ... third color filter, 16 ... transparent substrate, 17
... transparent electrode, 18 ... liquid crystal, 19 ... light, 20a, 20b ...
Phase difference plate, 21 ... Light source, 22 ... Light source system, 23 ... Switch.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical indication location G02B 5/30 (72) Inventor Tatsuhisa Fujii 3300 Hayano, Mobara-shi, Chiba Hitachi, Ltd. Electronic Devices Within the business unit

Claims (18)

[Claims] 1. A pair of substrates, at least one of which is transparent, electrodes provided on the substrates, a liquid crystal composition layer sandwiched between the substrates, and light transmission depending on an alignment state of liquid crystal molecules of the liquid crystal composition layer. Alternatively, in a liquid crystal display device including a liquid crystal cell having a polarization unit that changes a reflection characteristic and a driving unit that drives the liquid crystal layer, a light guide plate is provided on an upper surface of the liquid crystal cell, and light incident on the light guide plate is provided. A liquid crystal display device having a structure for guiding light to the surface of the liquid crystal cell. 2. A pair of substrates, at least one of which is transparent, electrodes provided on the substrates, a liquid crystal composition layer sandwiched between the substrates, and light transmission depending on an alignment state of liquid crystal molecules of the liquid crystal composition layer. Alternatively, in a liquid crystal display device comprising a liquid crystal cell having a polarizing means for changing a reflection characteristic and a driving means for driving the liquid crystal layer, an angle between a surface of the liquid crystal cell and a horizontal plane is 45 degrees or more, A light guide plate is provided on the upper surface of the cell, the angle between the surface of the light guide plate and the horizontal plane is less than 45 degrees, and the light guide plate has a structure for guiding light incident on the liquid crystal cell surface. Liquid crystal display device. 3. The liquid crystal display device according to claim 1, wherein a micro prism is provided on the lower surface of the light guide plate. 4. A reflection plate is provided on the lower side of the liquid crystal cell, and the reflection plate transmits light that has transmitted through the light guide plate and is incident on the surface of the liquid crystal cell mainly in a direction perpendicular to the surface of the liquid crystal cell. The liquid crystal display device according to claim 1, wherein the liquid crystal display device reflects the light. 5. The liquid crystal display device according to claim 4, wherein a transparent medium is filled between the liquid crystal cell and the reflection plate. 6. The liquid crystal display device according to claim 5, wherein any one of the surface of the light guide plate and the surface of the reflection plate is provided with a light scattering property. 7. The liquid crystal according to claim 6, wherein the polarizing means is a polarizing plate provided on the surface of the liquid crystal cell, and the interface of the polarizing plate with air is flat and has no light scattering property. Display device. 8. The liquid crystal display device according to claim 6, wherein the local surface structure of the reflector is a mirror surface structure. 9. The upper surface and the lower surface of the light guide plate, the surface of the reflection plate, and the surface of the interface of the polarizing plate with the air are locally flat and light transmissive, and the reflection is performed. The liquid crystal display device according to claim 5, wherein the plate is provided with light scattering properties. 10. The liquid crystal cell is provided with two or more kinds of color filters having different colors, the colors are different, and a light transmissive region is provided between the adjacent color filters and between the substrates. The liquid crystal display device according to claim 1. 11. The liquid crystal display device according to claim 10, wherein both of the two or more color filters having different colors and the light transmissive region are stripe-shaped. 12. The liquid crystal display device according to claim 10, wherein the area ratio of the region without the color filter is 20% or more. 13. The liquid crystal display device according to claim 11, wherein both the stripe-shaped color filter and the light transmissive region are substantially parallel to a horizontal plane. 14. The liquid crystal display device according to claim 1, wherein the liquid crystal composition layer and the polarizing means are arranged so as to have normally open characteristics. . 15. The liquid crystal display device according to claim 1, wherein the liquid crystal cell and the light guide plate are connected in a semi-fixed state, and an angle formed by the liquid crystal cell and the light guide plate can be adjusted. 16. The liquid crystal display device according to claim 15, wherein the liquid crystal cell and the light guide plate are folded so that their surfaces are parallel to each other and can be integrated. 17. A pair of substrates, at least one of which is transparent, electrodes provided on the substrates, a liquid crystal composition layer sandwiched between the substrates, and light transmission depending on the alignment state of liquid crystal molecules of the liquid crystal composition layer. Alternatively, in a liquid crystal display device including a liquid crystal cell having a polarization unit that changes a reflection characteristic, and a driving unit that drives the liquid crystal layer, a light guide plate is provided on an upper surface of the liquid crystal cell, and further above the light guide plate. A light source system including a light source is provided, the light source system has a structure for guiding the light incident on the light source system to the surface of the liquid crystal cell when the light source is not lit, and the light guide plate when the light source is lit. A liquid crystal display device having a structure in which light from the light source is guided to the surface of the liquid crystal cell by placing the light source system on the upper surface of. 18. The liquid crystal display device according to claim 17, further comprising a switch for automatically turning on the light source by placing a light reflecting plate on the upper surface of the light guide plate.