JP2003021836A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal display device which can observe an image from the front or the rear of a liquid crystal display part if necessary. SOLUTION: In the liquid crystal display device wherein light transmission and light reflection are performed in each pixel by means of a thin film formed on the surface on a liquid crystal side of one transparent substrate of respective transparent substrates disposed opposite to each other via a liquid crystal, a light for transmitting light over the entire area of the liquid crystal display part consisting at least the assembling body of each pixel is disposed opposite to the surface on the side opposite to the liquid crystal of the other transparent substrate of the respective transparent substrates.

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, and more particularly to an active matrix type liquid crystal display device which can be used in a light reflection mode or a light transmission mode.

[0002]

2. Description of the Related Art An active matrix type liquid crystal display device is a switching device which operates in response to a scanning signal from a gate signal line in each pixel region on the liquid crystal side of one of the substrates arranged to face each other via a liquid crystal. An element and a pixel electrode to which a video signal from the drain signal line is supplied via the switching element are provided.

An electric field is generated between the pixel electrode and another electrode (counter electrode) provided with the liquid crystal sandwiched therebetween, and the light transmittance of the liquid crystal is controlled by this electric field.

In such a liquid crystal display device, the pixel area is divided into two areas, one area having a pixel electrode having a light reflecting function and the other area having a pixel electrode having a light transmitting function. It is known that when formed, it can be used as a light reflection mode or a light transmission mode.

That is, by illuminating a backlight arranged on the back surface of a liquid crystal display device (liquid crystal display panel), the light is observed through the liquid crystal display device (through a pixel electrode having a light transmitting function). By irradiating the observer side to the light transmission mode and turning off the backlight, the observer side is illuminated by reflecting external light such as sunlight (reflecting the pixel electrode having a light reflecting function). The light reflection mode.

[0006]

However, the liquid crystal display device (liquid crystal display panel) having such a structure is
On the other hand, the image was observed from one side.

For this reason, when an electronic device incorporating the liquid crystal display device is created, the configuration is such that the liquid crystal display device is incorporated in a part of the housing of the electronic device. There are restrictions on the configuration of
It has been pointed out that a new and novel configuration that deviates from the limitation cannot be made.

Therefore, the present invention has been made under the above circumstances, and an object thereof is to provide a liquid crystal display device capable of observing an image from the front surface or the back surface of a liquid crystal display portion as needed. To do.

[0009]

Among the inventions disclosed in the present application, a brief description will be given to the outline of typical ones.
It is as follows.

Means 1. The liquid crystal display device according to the present invention is, for example, a device in which light is transmitted and reflected in each pixel by a thin film formed on a liquid crystal side surface of one transparent substrate facing each other with a liquid crystal interposed therebetween. A light is arranged to face the surface of the other transparent substrate of the transparent substrates opposite to the liquid crystal side and to transmit light over at least the entire area of the liquid crystal display unit including the aggregate of the pixels. It is characterized by being.

Means 2. The liquid crystal display device according to the present invention includes, for example, a semi-transmissive reflective film in each pixel region on the liquid crystal side surface of one of the transparent substrates that are arranged to face each other with the liquid crystal interposed therebetween. A light is arranged so as to face a surface of the other transparent substrate opposite to the liquid crystal side, and the light is arranged so as to face at least the entire liquid crystal display region formed of the aggregate of the pixel regions. It is characterized by comprising a light guide plate having an optical property and a light source for irradiating light into the light guide plate and emitting the light toward the other transparent substrate side.

Means 3. The liquid crystal display device according to the present invention includes, for example, a reflective film provided in a part of each pixel region on the liquid crystal side surface of one transparent substrate among the transparent substrates that are arranged to face each other with the liquid crystal interposed therebetween. A light is arranged so as to face the surface of the other transparent substrate opposite to the liquid crystal side, and the light is arranged so as to oppose at least the entire area of the liquid crystal display unit including the aggregate of the pixel regions. And a light source that irradiates the inside of the light guide plate and emits the light toward the other transparent substrate side.

Means 4. The liquid crystal display device according to the present invention includes, for example, a pixel region on the liquid crystal side of one of the substrates arranged to face each other with a liquid crystal interposed therebetween, and a pixel electrode, an insulating film, a part of the light transmissive pixel electrode from the substrate side. A light-reflecting pixel electrode having a hole or a notch is formed on the surface of the insulating film, and a large number of irregularities are formed on the surface of the insulating film.

Means 5. The liquid crystal display device according to the present invention includes, for example, a light-transmissive pixel electrode, an insulating film, and a light-reflective pixel electrode in the pixel region on the liquid crystal side of one of the substrates arranged to face each other with the liquid crystal interposed therebetween. Pixel electrode is formed,
A part of the insulating film is perforated to expose a part of the light-transmissive pixel electrode, and the light-reflective pixel electrode is provided in a region avoiding the insulating perforation. A color filter is formed in the formed hole of the insulating film.

Means 6. In the liquid crystal display device according to the present invention, the diffusion adhesive layer is formed on the light-side surface of the substrate on which the light is arranged, on the premise of any one of the means 1, 2, and 3. It is characterized by.

Means 7. In the liquid crystal display device according to the present invention, on the premise of any one of the means 1, 2, and 3, a retardation plate and a polarizing plate are provided on the surface of the substrate opposite to the side on which the light is arranged and opposite to the liquid crystal. Are arranged.

Means 8. In the liquid crystal display device according to the present invention, on the premise of any one of the means 1, 2 and 3, a diffusion adhesive layer is arranged on the surface of the substrate opposite to the side on which the light is arranged and opposite to the liquid crystal. It is characterized by being.

Means 9. A liquid crystal display device according to the present invention includes, for example, a housing containing an electronic circuit, and a liquid crystal display portion that can be opened and closed with one side of the housing as an axis, and the liquid crystal display portion has a surface on one side thereof. And that the image can be recognized from the surface on the other side.

Means 10. The liquid crystal display device according to the present invention,
For example, a case including an electronic circuit and a liquid crystal display unit that can be opened and closed around one side of the case as an axis are provided, and the liquid crystal display unit is one of transparent substrates arranged to face each other through a liquid crystal. A thin film formed on the liquid crystal side surface of one of the transparent substrates transmits and reflects light in each pixel, and on the surface of the other transparent substrate opposite to the liquid crystal side. It is characterized in that a light for transmitting light is arranged so as to face at least the entire area of the liquid crystal display portion including the aggregate of the respective pixels.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a liquid crystal display device according to the present invention will be described below with reference to the drawings.

Example 1. FIG. 2 is a plan view showing an embodiment of a unit pixel of the liquid crystal display device according to the present invention. The liquid crystal display portion of the liquid crystal display device is composed of a set of a large number of unit pixels arranged in a matrix, and FIG. 2 shows one unit pixel. Further, FIG. 1 shows a cross-sectional view taken along the line II of FIG.

First, in FIG. 2, a pair of gate signal lines GL extending in the x direction and juxtaposed in the y direction are formed on the surface of the transparent substrate SUB1 on the liquid crystal side.

These gate signal lines GL surround a rectangular region together with a pair of drain signal lines DL which will be described later, and this region is configured as a pixel region.

A transparent pixel electrode PX (T) made of, for example, an ITO (Indium-Tin-Oxide) film is formed on the upper surface of the transparent substrate SUB1 in this pixel region except the periphery thereof. ing.

The pixel electrode PX (T) functions as a pixel electrode in the light transmitting portion of the pixel area and is distinguished from the pixel electrode PX (R) in the light reflecting portion described later.

An insulating film GI made of, for example, SiN is formed on the surface of the transparent substrate SUB1 on which the gate signal line GL and the pixel electrode PX (T) are thus formed.
It is also formed so as to cover L and the pixel electrode PX (T) (see FIG. 1).

The insulating film GI functions as an interlayer insulating film for the gate signal line GL in the formation region of the drain signal line DL described later, and functions as a gate insulation film in the formation region of the thin film transistor TFT described later. In the formation region of the capacitive element Cadd, which will be described later, it has a function as a dielectric film.

On the surface of this insulating film GI,
A semiconductor layer AS made of, for example, amorphous Si is formed so as to overlap a part of the gate signal line GL.

This semiconductor layer AS is a thin film transistor T.
By forming the drain electrode SD1 and the source electrode SD2 on the upper surface of the FT, the MI of the inverted stagger structure in which a part of the gate signal line GL is used as the gate electrode.
An S-type transistor can be constructed. Here, the drain electrode SD1 and the source electrode SD2 are formed at the same time when the drain signal line DL is formed.

That is, the drain signal line DL extending in the y direction and arranged in parallel in the x direction in the drawing is formed, and a part of the drain signal line DL extends to the upper surface of the semiconductor layer AS to form the drain electrode SD1. The source electrode SD2 is formed so as to be separated from the drain electrode SD1 by the channel length of the thin film transistor TFT.

The source electrode SD2 extends slightly from the surface of the semiconductor layer AS to the upper surface of the insulating film GI on the pixel region side, and the pixel electrode PX (T) and the pixel electrode PX to be described later.
A contact portion is formed for connection with (R).

Source electrode SD2 and the pixel electrode PX
The connection with (T) is made through a contact hole CH1 formed in the insulating film GI.

The semiconductor layer AS and the drain electrode SD1
A thin layer doped with a high concentration of impurities is formed at the interface with the source electrode SD2, and this layer functions as a contact layer.

This contact layer is, for example, the semiconductor layer A.
When S is formed, a high-concentration impurity layer is already formed on the surface thereof, and the drain electrode SD1 formed on the upper surface of the impurity layer is formed.
And the impurity layer exposed from the pattern of the source electrode SD2 as a mask may be etched.

On the surface of the transparent substrate SUB1 on which the thin film transistor TFT, the drain signal line DL, the drain electrode SD1 and the source electrode SD2 are thus formed, a protective film PSV1 made of, for example, SiN and a protective film PSV2 made of an organic material are formed. Protective film PS consisting of sequentially laminated body
V is formed. The protective film PSV reduces the dielectric constant of the thin film transistor TFT, and thus the liquid crystal LC of the thin film transistor TFT.
A layer which avoids direct contact with the thin film transistor T
It is designed to prevent deterioration of FT characteristics.

Further, in this embodiment, a hole HO is formed in a part of the protective film PSV and the insulating film GI below the protective film PSV,
A part of the pixel electrode PX (T) is exposed. That is, the portion where the protective film PSV and the insulating film GI thereunder are perforated serves as a light transmissive portion in the pixel region, and the pixel electrode PX (T) exposed therefrom is exposed.
Serves as a substantial pixel electrode in the light transmitting portion.

It should be noted that perforation of the protective film PSV and the underlying insulating film GI is not always necessary, and is only preferable from the viewpoint of light absorption, for example.

The pixel electrode PX is formed on the upper surface of the protective film PSV.
(R) is formed. The pixel electrode PX (R) is made of, for example, a conductive film having a good light reflectance made of an aluminum (Al) film.

The pixel electrode PX (R) is formed in a portion other than the light transmitting portion that avoids the formation region of the thin film transistor TFT in the pixel region, and functions as a pixel electrode in the light reflecting portion. Therefore, the pixel electrode PX
(R) has a structure in which an opening is formed in a portion of the perforated HO formed in the protective film PSV and the insulating film GI below the protective film PSV.

Further, a part of the pixel electrode PX (R) is electrically connected to the source electrode SD2 of the thin film transistor TFT through a contact hole CH2 formed in a part of the protective film PSV.

Further, the pixel electrode PX (R) extends to above the other adjacent gate signal line GL different from the gate signal line GL driving the thin film transistor TFT connected thereto, and the other. Of the gate signal line GL is formed. In this portion, the protective film P is provided between the pixel electrode PX (R) and another gate signal line GL.
A capacitive element Cadd having a laminated body of the SV and the insulating film GI as a dielectric film is formed. The capacitive element Cadd is provided, for example, with pixel electrodes PX (T) and PX.
The video signal supplied to (R) has a function of accumulating for a relatively long time.

The pixel electrode PX is formed on the upper surface of the transparent substrate SUB1 on which the pixel electrode PX (R) is formed.
An alignment film ORI1 is formed so as to cover (R) as well. This alignment film ORI1 is a film that directly contacts the liquid crystal LC, and the rubbing formed on the surface thereof determines the initial alignment direction of the molecules of the liquid crystal LC.

A retardation plate PH1 and a polarizing plate POL1 are sequentially arranged on the surface of the transparent substrate SUB1 opposite to the liquid crystal side via an adhesive material AD'1.
1 and the polarizing plate POL1 constitute a so-called anti-glare polarizing plate. The retardation plate PH1 is not always necessary and may be omitted.

A black matrix BM is formed on the surface of the transparent substrate SUB2 facing the transparent substrate SUB1 via the liquid crystal LC on the liquid crystal side so as to define each pixel area. That is, at least the black matrix BM formed in the liquid crystal display section has a pattern in which an opening is formed in the area where the peripheral portion of each pixel area is left, thereby improving the display contrast (reference numeral BM in FIG. 2). reference).

The black matrix BM is formed so as to sufficiently cover the thin film transistor TFT on the transparent substrate SUB1 side, and the thin film transistor TF is prevented by irradiating external light to the thin film transistor TF.
The characteristic deterioration of T is avoided.

A color filter FIL is formed on the surface of the transparent substrate SUB2 on which the black matrix BM is formed so as to cover the openings of the black matrix BM. This color filter FIL is, for example, red (R), green (G),
A red filter is formed in common in each pixel region group that is arranged in parallel in the y direction and that is composed of filters of each color of blue (B), and is commonly shared by the pixel region groups that are sequentially adjacent to the pixel region group in the x direction. Red (R) color, green (G) color, blue (B) color, red (R)
The colors are arranged in an array. Each of these filters is composed of a resin film containing a pigment corresponding to that color.

The black matrix BM and the color filter FI are formed on the surface of the transparent substrate SUB2 on which the black matrix BM and the color filter FIL are formed.
A transparent conductive film made of, for example, an ITO film is formed so as to cover L as well, and the counter electrode CT common to each pixel region is formed by this conductive film.

An alignment film ORI is formed on the surface of the counter electrode CT.
2 is formed, and this alignment film ORI2 is a film that directly contacts the liquid crystal LC, and the rubbing formed on the surface thereof determines the initial alignment direction of the molecules of the liquid crystal LC.

A retardation plate PH2 and a polarizing plate POL2 are sequentially arranged on the surface of the transparent substrate SUB1 opposite to the liquid crystal side with a diffusion adhesive material AD interposed therebetween. Here, the diffusion adhesive material AD is formed by mixing beads or the like in the adhesive material, and has a function of scattering and emitting light incident by the beads or the like. The beads are made of substantially the same material as the beads BS mixed in the liquid crystal LC in order to make the gap between the transparent substrate SUB1 and the transparent substrate SUB2 uniform.

Further, in the liquid crystal display device having such a configuration, the transparent substrate SUB2, that is, the pixel electrode PX (T) that transmits light and the pixel electrode PX (R) that reflects light are formed transparent. The front light FL is arranged on the surface of the other transparent substrate SUB2 different from the substrate SUB1 on the opposite side of the liquid crystal. This front light F
L is a light guide plate made of a transparent material, which is arranged to face the transparent substrate SUB2, and a linear light source arranged along the side wall of the light guide plate (for example, a cold cathode ray tube: not shown).
It consists of and.

In the liquid crystal display device thus configured, as shown in FIG. 3 showing the whole of the liquid crystal display device, the observer is positioned on the transparent substrate 2 side, for example, and the front light F is used.
The liquid crystal display device can be viewed through L.

In this case, the observer uses the front light F
It is possible to turn off the L and recognize the image displayed on the liquid crystal display unit of the liquid crystal display device by using external light such as sunlight (mode (1)). That is, the external light passes through the front light FL, the transparent substrate SUB2, and the liquid crystal LC, and is reflected by the pixel electrode PX (R), so that the liquid crystal LC and the transparent substrate SU.
The eyes of the observer are reached through B2 and the front light FL. Similarly, the image displayed on the liquid crystal display unit of the liquid crystal display device can be recognized by turning on the front light FL (mode (2)).

Further, the observer can also see the liquid crystal display device, for example, located on the transparent substrate 1 side.

In this case, the observer uses the front light F
By lighting L, the image displayed on the liquid crystal display unit of the liquid crystal display device can be recognized (mode (3)). That is, the light of the front light FL is transmitted through the transparent substrate SUB2 and the liquid crystal LC, and further transmitted through the pixel electrode PX (T).
The observer's eyes are reached through UB1.

Therefore, the liquid crystal display portion of the liquid crystal display device can be observed not only from one side but also from the other side.

In this case, in the case of an image in which left-right reversal is not a particular problem, it is not necessary to switch the supply of video signals, but in the case of displaying characters, etc., the supply of video signals, etc. Switching will allow them to be observed without hindrance.

In the configuration of the above-described embodiment, since the diffusion adhesive material layer AD is formed on the surface of the transparent substrate SUB2 on the front light FL side, the mode (1) shown in FIG.
Alternatively, the light shown in the mode (2) is diffused by the diffusion adhesive material layer AD, and it is possible to prevent the reflection due to so-called specular reflection.

Example 2. FIG. 4 is a constitutional view showing another embodiment of the liquid crystal display device according to the present invention and corresponds to FIG.

The configuration different from that of FIG. 1 is that a retardation plate PH1 and a polarizing plate POL1 are formed on the surface of the transparent substrate SUB1 opposite to the liquid crystal LC via a diffusion adhesive material layer AD2. The diffusion adhesive layer AD2 is formed by mixing beads in the adhesive layer.

In this case, since the light incident from the surface of the transparent substrate SUB1 on the side opposite to the liquid crystal LC is diffused by the diffusion adhesive layer AD2, it is possible to prevent reflection due to so-called specular reflection. .

In the case of this embodiment, the transparent substrate SUB
The retardation film PH2 and the polarizing plate POL2 are also formed on the surface of the second liquid crystal LC opposite to the liquid crystal LC, so that the light is incident from the surface of the transparent substrate SUB2 opposite the liquid crystal LC. Light is also diffused by the diffusion adhesive layer AD.

Example 3. FIG. 5 is a constitutional view showing another embodiment of the liquid crystal display device according to the present invention and corresponds to FIG.

The structure different from FIG. 1 is as follows. First, the transparent substrate SU.
On the liquid crystal side surface of B2, for example, the black matrix B
M, the upper surface of the color filter FIL, and the counter electrode C
A diffusion overcoat layer DOC is formed on the lower surface of T. The diffusion overcoat layer DOC is formed by mixing beads in an organic material layer, for example.

The diffusion overcoat layer DOC has the same function as that of the diffusion adhesive material AD, whereby the retardation plate P formed on the surface of the transparent substrate SUB2 opposite to the liquid crystal.
H2 and the polarizing plate POL2 are formed via a normal adhesive material layer AD'1.

In the liquid crystal display device thus constructed, the light incident from the surface of the transparent substrate SUB2 on the side opposite to the liquid crystal LC is diffused by the diffusion overcoat layer DOC, and is reflected by specular reflection. Can be prevented.

Further, as compared with the case of the diffusion adhesive material AD formed on the surface of the transparent substrate SUB2 opposite to the liquid crystal LC,
The effect of preventing blurring of the display image itself in the reflective display is exerted. By the way, when the diffusion adhesive material layer AD is formed on the surface of the transparent substrate SUB2 opposite to the liquid crystal LC, the distance between the pixel electrode PX (R) having a light reflecting function and the diffusion adhesive material layer AD is This corresponds to the thickness of the SUB2 and is two digits or more than the layer thickness (several μm) of the liquid crystal layer, and the display image itself of the reflective display is blurred.

Example 4. FIG. 6 is a constitutional view showing another embodiment of the liquid crystal display device according to the present invention and corresponds to FIG.

The structure different from that of FIG. 5 is the transparent substrate S.
Phase difference plate PH arranged on the surface of UB1 opposite to the liquid crystal
1. The polarizing plate POL1 is formed via the diffusion adhesive layer AD.

As a result, the liquid crystal LC of the transparent substrate SUB2
The light incident from the surface on the opposite side to the diffusion adhesive layer AD
It is possible to prevent the reflection due to the specular reflection.

Example 5. FIG. 7 is a constitutional view showing another embodiment of the liquid crystal display device according to the present invention and corresponds to FIG.

A difference from the structure shown in FIG. 6 is that the pixel electrode PX (R) functioning as a light reflecting electrode is formed on the protective film PSV having the unevenness formed on its surface.

This pixel electrode PX (R) is a transparent substrate SU.
B1 and the transparent substrate SUB2 each reflect the light incident respectively, and said protective film PSV
These functions can be simultaneously provided by the uneven treatment of the surface of the chisel.

Example 6. FIG. 8 is a constitutional view showing another embodiment of the liquid crystal display device according to the present invention and corresponds to FIG.

The structure different from that of FIG. 7 is that the insulating film GI, the protective film PVS1,
The transparent substrate SUB2 is formed in the recess formed in the protective film PVS2.
This is because a color filter of the same color as the color filter FIL formed on the side is embedded and formed.

The liquid crystal display device having such a structure can obtain a display with high color purity when displaying in the light transmission mode.

In the case of a liquid crystal display device that also serves as a reflective display, the reflective display is generally performed with priority on the luminance, and the built-in color filter FIL is of a relatively pale color. Therefore, it is possible to eliminate the inconvenience that the brightness becomes low even in the case of the transmissive display with the above-described configuration.

Example 7. FIG. 9 is a constitutional view showing another embodiment of the liquid crystal display device according to the present invention and corresponds to FIG.

The structure different from that of FIG. 8 is the transparent substrate S.
The color filter FIL formed in the UB2 is not provided in particular.

As a result, black and white display is performed in the light reflection display mode, and the transparent substrate S is displayed in the light transmission display mode.
Color display is performed by the color filter FIL formed by being superimposed on the pixel electrode PX (T) on the UB1 side.

That is, in the light reflection display mode, the brightness is prioritized for monochrome display, and in the light transmission display mode, the image quality is prioritized for color display.

Example 8. In the liquid crystal display device shown in each of the above-described embodiments, the display can be recognized from either side of the transparent substrates SUB1 and SUB2.

Therefore, the frame FR for modularizing the liquid crystal display device (liquid crystal display panel PNL) and the front light FL is, for example, as shown in FIG. 10A, a laminate of the liquid crystal display panel PNL and the front light FL. It is formed around the body, and at least the liquid crystal display panel PNL does not have a light blocking member that covers the liquid crystal display portions on the front and back surfaces thereof.

From this fact, in addition to the frame FR,
If a member formed as a part of the frame FR is required, for example, as shown in FIG. 10B, the liquid crystal of the liquid crystal display panel PNL is provided on the side opposite to the side on which the front light FL is arranged. The transparent member TM may be formed so as to cover the display portion.

Further, it goes without saying that a so-called touch panel may be arranged at that portion instead of the transparent member TM in this case.

Here, the touch panel refers to a plate-shaped electronic member that outputs position information of the pressed point without hindering the image display by the liquid crystal display panel PNL.

Example 9. In each of the above-mentioned embodiments,
Each pixel region is provided with a light-reflective pixel electrode and a light-transmissive pixel electrode, and each electrode constitutes a light-reflecting mode and a light-transmitting mode.

However, the present invention is not limited to such a configuration, and is formed of a material layer (for example, a layer in which an Al layer is formed relatively thin) capable of simultaneously transmitting and reflecting light in one pixel electrode. Of course, this may be a configuration in which the light reflection mode and the light transmission mode are combined.

Example 10. FIG. 11 is a diagram showing an embodiment in which the liquid crystal display device described above is applied to a mobile phone. Figure 1
1 (a) shows the case of using as a telephone, and FIG.
(B) shows the case of using as an information terminal.

The portable telephone according to the present embodiment has a casing CAS in which a keyboard, buttons, or switches are formed, and circuits which are connected to them are built in, and one side of the casing CAS. It is composed of a liquid crystal display section LD which can be opened and closed as a base axis.

As described above, the liquid crystal display panel built in the liquid crystal display unit LD can recognize images from both sides thereof.
As shown in FIG. 11A 'when the mobile phone of FIG. 11A is viewed from the side, the side of the liquid crystal display LD which is closed with respect to the casing CAS can be viewed by the telephone operator (for example, the transparent substrate S).
The liquid crystal display unit on the UB1 side) is observed.

When used as an information terminal,
FIG. 11 is a side view of the mobile phone of FIG.
As shown in (b '), the liquid crystal display unit on the side (for example, the transparent substrate SUB2 side) of the liquid crystal display unit LD opened with respect to the casing CAS can be viewed by the telephone operator. .

In this case, the image display in the liquid crystal display area of each liquid crystal display unit is configured to be switched by, for example, a switch for detecting opening / closing of the liquid crystal display unit LD with respect to the casing CAS.

Example 11. FIGS. 12A and 12B are configuration diagrams showing another embodiment of the liquid crystal display device according to the present invention and correspond to FIGS. 11A and 11B. Figure 11
In the configuration different from that of the first embodiment, first, the liquid crystal display area on the side used for telephone operation of the liquid crystal display LD is formed to be relatively small.

The outer contour of the liquid crystal display area is formed by extending the liquid crystal display panel PNL in a part of the frame FR, for example.

Then, a telephone operation button is arranged in the extended portion of the frame FR in the extra space corresponding to the smaller liquid crystal display area.

In this case, for example, as shown in FIG. 12C showing a cross section of the liquid crystal display section LD, the front light FL is arranged on the side to be viewed when used as a telephone.
The telephone operator recognizes the display in the reflective display mode regardless of whether the front light FL is on or off.

When used as an information terminal, the operator of the information terminal recognizes the display by the light transmitted from the front light FL to the liquid crystal display device, that is, in the transmissive display mode.

Further, the circuit CRC connected to the telephone operation button can be incorporated in the extending portion of the frame FR which defines the liquid crystal display area when used as a telephone, as shown in FIG. 13, for example. It has become.

Example 12. 14A and 14B are configuration diagrams showing another embodiment of the liquid crystal display device according to the present invention.
The drawings correspond to FIGS. 12A and 12B, respectively.

In this embodiment, when used as a telephone, characters and the like displayed in the liquid crystal display area when viewed from the button side are displayed horizontally, and when used as an information terminal, viewed from the keyboard side. It is designed to be displayed horizontally.

When used as a telephone, since the liquid crystal display area is narrow, the driving frequency is lowered and the number of drawing lines per frame is reduced for driving. On the other hand, when used as an information terminal, the driving frequency is higher and the number of drawing lines per frame is larger than when used as a telephone.

In this case, since the area of the liquid crystal display portion of the liquid crystal display device used is different between the case of using as a telephone and the case of using as an information terminal, as shown in FIG. A light source (for example, a light emitting diode LED) of the front light FL is arranged on each of a pair of opposite sides of the light guide plate, and when used as a telephone, one light source close to the liquid crystal display unit is turned on to serve as an information terminal. It goes without saying that both of the light sources may be turned on when used.

[0103]

As is apparent from the above description,
According to the liquid crystal display device of the present invention, an image can be observed from the front surface or the back surface of the liquid crystal display section as needed.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of a liquid crystal display device according to the present invention, and is a cross-sectional view taken along line I-I of FIG.

FIG. 2 is a plan view showing an embodiment of a liquid crystal display device according to the present invention.

FIG. 3 is an explanatory diagram showing respective light paths of a light reflection mode and a light transmission mode of the liquid crystal display device according to the present invention.

FIG. 4 is a configuration diagram showing another embodiment of the liquid crystal display device according to the present invention.

FIG. 5 is a configuration diagram showing another embodiment of the liquid crystal display device according to the present invention.

FIG. 6 is a configuration diagram showing another embodiment of the liquid crystal display device according to the present invention.

FIG. 7 is a configuration diagram showing another embodiment of the liquid crystal display device according to the present invention.

FIG. 8 is a configuration diagram showing another embodiment of the liquid crystal display device according to the present invention.

FIG. 9 is a configuration diagram showing another embodiment of the liquid crystal display device according to the present invention.

FIG. 10 is an explanatory diagram showing a housing for modularization in the liquid crystal display device according to the present invention.

FIG. 11 is a configuration diagram showing an embodiment in which the liquid crystal display device according to the present invention is applied to a mobile phone.

FIG. 12 is a configuration diagram showing another embodiment in which the liquid crystal display device according to the present invention is applied to a mobile phone.

FIG. 13 is a configuration diagram showing another embodiment in which the liquid crystal display device according to the present invention is applied to a mobile phone.

FIG. 14 is a configuration diagram showing another embodiment in which the liquid crystal display device according to the present invention is applied to a mobile phone.

[Explanation of symbols]

SUB ... Transparent substrate, GL ... Gate signal line, DL ... Drain signal line, GI ... Insulating film, PSV ... Insulating film, PX (T)
... Pixel electrode having a light transmitting function, PX (R) ... Pixel electrode having a light reflecting function, CT ... Counter electrode, PH ... Phase difference plate, POL ... Polarizing plate, AD ... Diffusion adhesive material layer, FL ...
Front light.

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) G09F 9/40 303 G09F 9/40 303 (72) Inventor Kazuhiko Yanagawa 3300 Hayano, Mobara-shi, Chiba Hitachi, Ltd. Display Group F term (reference) 2H091 FA02Y FA08X FA08Z FA11X FA11Z FA14Y FA15Y FA23X FA23Z FA31Y FA41X FA41Z FD06 LA15 LA16 LA30 5C094 AA01 AA12 BA03 BA43 CA19 CA20 CA24 EA04 EA07 ED03 ED11

Claims (10)

[Claims] 1. A thin film formed on a liquid crystal side surface of one of the transparent substrates facing each other with a liquid crystal interposed therebetween to allow light transmission and light reflection in each pixel. A light is arranged to face the surface of the other transparent substrate of the other transparent substrate opposite to the liquid crystal side, and to transmit light over at least the entire area of the liquid crystal display unit including the aggregate of the pixels. Characteristic liquid crystal display device. 2. A semi-transmissive reflective film is provided in each pixel region on a liquid crystal side surface of one transparent substrate facing each other across the liquid crystal, and the other transparent substrate is transparent. A light is arranged so as to face the surface of the substrate opposite to the liquid crystal side, and the light is a light-transmitting light guide plate that is arranged so as to oppose at least the entire liquid crystal display region including the aggregate of the pixel regions. And a light source that irradiates light into the light guide plate and emits light to the other transparent substrate side. 3. A transparent film is provided in a part of each pixel region on a liquid crystal side surface of one transparent substrate facing each other across a liquid crystal, and the other transparent substrate of the transparent substrates is provided. A light is arranged so as to face the surface opposite to the liquid crystal side of the light. A liquid crystal display device, comprising: a light source that irradiates light into the light guide plate and emits light toward the other transparent substrate side. 4. A pixel region on the liquid crystal side of one of the substrates opposed to each other with a liquid crystal in between, and a pixel electrode that is transparent to light from the substrate side, an insulating film, and a hole or cut in a part. A liquid crystal display device, wherein a light-reflective pixel electrode having a notch is formed, and a large number of irregularities are formed on the surface of the insulating film. 5. A light-transmissive pixel electrode, an insulating film, and a light-reflective pixel electrode are provided from the substrate side to a liquid crystal side pixel region of one of the substrates opposed to each other via a liquid crystal. A part of the insulating film is perforated to expose a part of the light transmissive pixel electrode, and the light reflective pixel electrode avoids the insulating perforated portion. A liquid crystal display device, characterized in that a color filter is formed in the region where the insulating film is formed, and a color filter is formed in the perforated portion of the insulating film. 6. The liquid crystal according to claim 1, wherein a diffusion adhesive material layer is formed on the light-side surface of the substrate on which the light is arranged. Display device. 7. The retardation plate and the polarizing plate are arranged on the surface of the substrate opposite to the side on which the light is arranged opposite to the liquid crystal. The liquid crystal display device according to any one of claims. 8. The diffusion adhesive layer is disposed on the surface of the substrate opposite to the side on which the light is disposed opposite the liquid crystal, and the diffusion adhesive layer is disposed on the surface opposite to the liquid crystal. The liquid crystal display device according to item 1. 9. A housing including an electronic circuit, and a liquid crystal display unit that can be opened and closed around one side of the housing as an axis, wherein the liquid crystal display unit has a surface on one side and a surface on the other side. Mobile phone characterized by being able to recognize images from the surface. 10. A housing containing an electronic circuit, and a liquid crystal display unit which can be opened and closed around one side of the housing as an axis, wherein the liquid crystal display unit is arranged so as to face each other through a liquid crystal. A thin film formed on the liquid crystal side surface of one of the transparent substrates transmits and reflects light in each pixel, and the other side of the transparent substrate is opposite to the liquid crystal side. A mobile phone, wherein a light for transmitting light is arranged so as to face at least the entire area of a liquid crystal display portion including the aggregate of the pixels.