JP2003228059A - Liquid crystal display device and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display device capable of realizing high quality display resistant to display unevenness caused by large resistance values of electrodes, thinning thickness of the electrodes, reducing resistance values of wiring to be routed, and narrowing the frame. <P>SOLUTION: In the liquid crystal display device, a polarizer layer arranged at least on either of the upper substrate 3 and the lower substrate 2 is provided with a reflecting polarizer layer 6 where a plurality of minute slit-like openings are arranged in a metallic reflecting film, and the reflecting polarizer layer 6 is at least partly in contact with a transparent electrode 8 arranged on the same substrate as the one provided with the reflecting polarizer layer 6. <P>COPYRIGHT: (C)2003,JPO

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 an electronic device, and in particular, it is possible to realize a high-quality display in which uneven display due to a large resistance value of an electrode hardly occurs.
The present invention relates to a liquid crystal display device in which the thickness of electrodes can be reduced, the resistance value of a lead-out wiring is small, and miniaturization can be achieved, and an electronic apparatus including the same.

[0002]

2. Description of the Related Art A reflection type liquid crystal display device has a small power consumption because it does not have a light source such as a backlight, and has been widely used in various portable electronic devices and an accessory display unit of the device. However, there is a problem that it is difficult to visually recognize the display in a dark place because the display is performed by using external light such as natural light or illumination light. Therefore, there has been proposed a liquid crystal display device in which outside light is used in a bright place like a normal reflection type liquid crystal display device, but in a dark place the display can be visually recognized by an internal light source. In other words, this liquid crystal display device employs a display system that has both a reflective type and a transmissive type, and power consumption is reduced by switching to either a reflective mode or a transmissive mode display system depending on the ambient brightness. In the meanwhile, the display can be made clear even when the surroundings are dark. Hereinafter, in this specification, a liquid crystal display device of this type is referred to as a "semi-transmissive reflective liquid crystal display device".
Say.

[0003]

However, the conventional liquid crystal display device has a problem that the brightness in the transmissive mode is insufficient as compared with the reflective mode. This is because the amount of light that can mainly contribute to the display in the transmissive mode is only the amount of light that has passed through the slit provided in the reflective film, and that the quarter-wave plate and the polarizing plate provided on the outer surface side of the lower substrate. It is due to.

More specifically, when displaying in a transmissive mode in a conventional liquid crystal display device, the light emitted from the backlight enters the liquid crystal display unit from the outside of the lower substrate, and out of this light. Only the light that has passed through the slit becomes the light that contributes to the display. Here, focusing on the light that does not pass through the slit, of the light emitted from the backlight, the light that is reflected on the back surface side of the reflective film without passing through the slit is almost entirely reflected by the lower polarizing plate of the lower substrate. Will be absorbed. Furthermore, focusing on the case of performing bright display in the transmission mode, the light that has entered the liquid crystal through the slit is
The light is emitted to the upper side of the liquid crystal display device through the upper polarizing plate of the upper substrate without being affected by the liquid crystal, but about half of the light is absorbed by the upper polarizing plate when passing through the upper polarizing plate.

Therefore, in order to solve such a problem, a liquid crystal display device having a structure shown in FIG. 8 has been proposed.
The liquid crystal display device 200 shown in FIG. 8 includes a pair of transparent substrates 20.
A liquid crystal 203 is sandwiched between 1 and 202, a reflective polarizing layer 204 and an insulating layer 206 are laminated on a lower substrate 201, and a stripe-shaped scanning electrode 208 made of a transparent conductive film such as ITO is formed on the reflective polarizing layer 204 and an insulating layer 206. An alignment film 207 is formed so as to cover the scan electrodes 208. On the other hand, a color filter 209 is formed on the upper substrate 202, a flattening film 211 is laminated on the color filter 209, and ITO is formed on the flattening film 211.
The signal electrode 212 made of a transparent conductive film such as
8 is formed in a stripe shape in a direction orthogonal to 8 and an alignment film 213 is formed so as to cover the signal electrode 212.

The reflective polarizing layer 204 is formed by forming a fine opening having a width of about 50 nm in a slit shape at a pitch of 150 nm to 400 nm on a metal film such as aluminum. The light incident on the reflective polarization layer 204 is such that polarized light parallel to the slit-shaped opening is reflected and polarized light perpendicular to the opening is transmitted. In addition, the upper substrate 202
On the outer side of the front scattering plate 218 in order from the upper substrate 202 side,
A retardation plate 219 and an upper polarization plate 214 are arranged. Further, the backlight 217 is arranged on the lower surface side of the lower substrate 201.

In the liquid crystal display device 200 having the above structure, in the transmissive mode, the light incident on the upper polarizing plate 214 is not the circularly polarized light but the linearly polarized light, so that the display in the transmissive mode can be brightened. In addition, the reflective polarization layer 20
The light reflected by No. 4 is returned to the backlight 217, and while repeating reflection between the reflective polarization layer 204 and the backlight 217, the polarization state changes and can be transmitted through the reflective polarization layer 204. The light of the backlight 217 can be effectively used.

However, in the liquid crystal display device 200 having the above structure, the scanning electrode 208 generally formed of ITO is used.
Due to the large resistance value of the signal electrode 212 and the signal electrode 212, the signal waveform may be blunted and display unevenness such as crosstalk may occur. In order to solve this problem, it is conceivable to increase the thickness of the scanning electrodes 208 and the signal electrodes 212 to reduce the resistance of the scanning electrodes 208 and the signal electrodes 212. If the thickness is increased, the time required to form the scan electrodes 208 and the signal electrodes 212 becomes longer, which is not preferable in the manufacturing process. Therefore, the scan electrode 208 and the signal electrode 2 can be formed without increasing the thickness of the scan electrode 208 and the signal electrode 212.
It was required to lower the resistance of No. 12.

The present invention has been made in order to solve the above problems, and it is possible to realize a high-quality display in which uneven display due to a large resistance value of an electrode is unlikely to occur and to reduce the thickness of the electrode. A first object of the present invention is to provide a liquid crystal display device capable of achieving a narrow frame with a small wiring resistance. A second object of the present invention is to provide an electronic device equipped with the above excellent liquid crystal display device.

[0010]

In order to achieve the above object, in a liquid crystal display device of the present invention, a liquid crystal is sandwiched between an upper substrate and a lower substrate facing each other, and the upper substrate and the lower substrate are provided. A liquid crystal display device having a transparent electrode and a polarizing layer respectively, wherein the polarizing layer provided on at least one of the upper substrate and the lower substrate has a plurality of fine slit-shaped metal reflection films. A reflective polarizing layer provided with an opening of the reflective polarizing layer, wherein the reflective polarizing layer is at least partially in contact with the transparent electrode provided on the same substrate as the substrate on which the reflective polarizing layer is provided. And

The liquid crystal display device of the present invention comprises a reflective polarizing layer made of a metal reflective film as the polarizing layer, and at least a part of the reflective polarizing layer is in contact with the transparent electrode.
At least a part of the reflective polarizing layer can function as an electrode. Therefore, the function of the transparent electrode as an electrode can be supplemented by a reflective polarizing layer that is a metal reflective film,
The resistance value of the electrode can be reduced. As a result, it is possible to prevent the inconvenience that the resistance value of the transparent electrode is large and the signal waveform is blunted to cause display unevenness, and high quality display can be realized. Further, since the resistance value of the electrode can be reduced, the thickness of the transparent electrode can be reduced, the amount of the material forming the transparent electrode can be reduced, and the time required for manufacturing can be shortened. You can

In the liquid crystal display device of the present invention,
An illumination device is provided on the outer surface side of the lower substrate, which is a transflective liquid crystal display device that performs display by switching between a transmissive mode and a reflective mode, and the lower substrate includes the reflective polarizing layer. It may be characterized by. By using such a liquid crystal display device, it is possible to prevent the inconvenience that the signal waveform is blunted due to the large resistance value of the transparent electrode and the display unevenness is generated, and the semi-transmissive reflection capable of realizing a high quality display. Type liquid crystal display device is obtained. Further, since the resistance value of the electrodes can be reduced, it is possible to obtain a transflective liquid crystal display device having a thin transparent electrode.

Further, in the liquid crystal display device of the present invention,
It is desirable that the transparent electrode provided on the substrate provided with the reflective polarizing layer is provided so as to cover the surface of the reflective polarizing layer on the liquid crystal side. If, in order to obtain a reflective polarizing layer having a large reflectance, the reflective polarizing layer is made of silver or a silver alloy having a large reflectance among metals,
Assuming that the liquid crystal side surface of the reflective polarizing layer is not covered with a transparent electrode, the surface of the reflective polarizing layer made of silver or a silver alloy is used in the step of forming an alignment film which is a step after the reflective polarizing layer is formed. The heat may form irregularities, and the reflective polarizing layer may turn yellow to hinder display.

On the other hand, in the above liquid crystal display device, the transparent electrode provided on the substrate provided with the reflective polarizing layer is provided so as to cover the surface of the reflective polarizing layer on the liquid crystal side. Therefore, in the process of forming the alignment film, the surface of the reflective polarizing layer is protected by the transparent electrode. Therefore, even when the reflective polarizing layer is made of silver or a silver alloy, unevenness is not formed on the surface of the reflective polarizing layer due to heat in the process of forming the alignment film, and Yellowing of the reflective polarizing layer due to heat in the forming process can be prevented, and high-quality display can be realized.

Further, in the above liquid crystal display device, it is preferable that the transparent electrode is provided on a substrate provided with the reflective polarizing layer, and the reflective polarizing layer is provided on the transparent electrode.

For example, when the reflective polarizing layer is made of silver or silver alloy having a high reflectance among metals, the substrate is made of glass, and when the reflective polarizing layer is directly provided on the substrate, silver or silver alloy and glass are used. There may be a problem that the adhesiveness with is not good. On the other hand, in the above liquid crystal display device, the transparent electrode is provided on the substrate on which the reflective polarization layer is provided, and the reflective polarization layer is provided on the transparent electrode. The transparent electrode is provided between the substrate provided with the layer and the reflective polarizing layer. Therefore, the material forming the reflective polarizing layer or the substrate can be determined regardless of whether the adhesion between the substrate and the reflective polarizing layer is good or bad. For example, the reflective polarizing layer is made of silver or a silver alloy, and the substrate Even if the glass is made of glass, there is no problem that the adhesion between silver and a silver alloy and the glass is not good. Therefore, among metals, silver or silver alloy having a high reflectance can be preferably used as a material for forming the reflective polarizing layer.

In the above liquid crystal display device, it is desirable that the reflective polarizing layer is made of silver or silver alloy.
By using such a liquid crystal display device, a reflective polarizing layer having a high reflectance is provided. As a result, light can be used for display more efficiently, and a liquid crystal display device having excellent display brightness can be realized. Also,
By using such a liquid crystal display device, a reflective polarizing layer having a small resistance value can be obtained, so that the function of the transparent electrode as an electrode can be effectively supplemented by the reflective polarizing layer, and the resistance value of the electrode can be sufficiently increased. Can be made smaller.

Further, in the above-mentioned liquid crystal display device, the transparent electrode provided on the substrate provided with the reflective polarizing layer is formed in a stripe shape, and the length direction of the slit-shaped opening is It is desirable that the direction is substantially parallel to the extending direction of the transparent electrode formed in a stripe shape.
For example, when the reflective polarizing layer is made of silver or a silver alloy, the transparent electrode is made of ITO, and the length direction of the slit-shaped opening is orthogonal to the extending direction of the transparent electrode,
This means that ITO and silver or silver alloy are connected in series. Therefore, the resistance value is limited by the ITO resistance. On the other hand, when the length direction of the slit-shaped opening is parallel to the extending direction of the transparent electrode, it means that ITO and silver or silver alloy are connected in parallel. Therefore, the resistance of silver or silver alloy is extremely low. Therefore, when the length direction of the slit-shaped opening is substantially parallel to the extending direction of the transparent electrode formed in a stripe shape, the length direction of the opening is the extending direction of the transparent electrode. A resistance value that is two orders of magnitude lower than that in the case of the substantially orthogonal direction is obtained.

Further, in the above-mentioned liquid crystal display device, a lead wiring for electrically connecting the transparent electrode and the liquid crystal driving element is provided, and the lead wiring is at least the transparent conductive film and the transparent conductive film. It is desirable that a part of the metal film is provided in contact with the metal film.

In such a liquid crystal display device, since the lead-out wiring is composed of the transparent conductive film and the metal film provided at least partially in contact with the transparent conductive film, the transparent conductive film of the transparent conductive film is formed. The function of the routing wiring can be supplemented by the metal film, and the resistance value of the routing wiring can be reduced. Therefore, the routing wiring can be thinned, and the space for arranging the routing wiring can be narrowed, so that the non-display area around the effective display area in the liquid crystal display device (hereinafter, referred to as " It is also possible to reduce the area of the frame area). Since such a liquid crystal display device can reduce the area of the frame region, in particular, the liquid crystal display device is housed in the limited space in the housing and the information is displayed on the occupied area. It is suitable for use in portable small electronic devices such as mobile phones that require a large area.

Further, in the above liquid crystal display device, it is preferable that the transparent conductive film is provided on a substrate provided with the metal film, and the metal film is provided on the transparent conductive film. . In such a liquid crystal display device, since the transparent conductive film is provided between the substrate provided with the metal film and the metal film, the adhesion between the substrate and the metal film is improved. The material forming the metal film or the substrate can be determined regardless of whether it is good or bad. Therefore, for example, even when the metal film is made of silver or a silver alloy and the substrate is made of glass,
Poor adhesion between silver or silver alloy and glass does not pose a problem. Therefore, silver or a silver alloy can be preferably used as the material forming the metal film.

Further, in the above liquid crystal display device, it is preferable that the metal film is a metal reflection film provided with a plurality of fine slit-shaped openings. By using such a liquid crystal display device, it becomes possible to form the metal film forming the routing wiring at the same time as the reflective polarizing layer,
It is possible to realize a liquid crystal display device in which routing wiring can be easily formed.

In order to achieve the above-mentioned object, the electronic equipment of the present invention is characterized by including the above-mentioned liquid crystal display device of the present invention. According to such an electronic device, it is possible to realize an electronic device having an excellent display unit.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a partial cross-sectional structure of the liquid crystal display device of the present embodiment. In this embodiment, a passive matrix type transflective color liquid crystal display device will be described as an example. In addition, in the following drawings, in order to make the drawings easy to see, the film thicknesses and the dimensional ratios of the respective components are appropriately changed.

As shown in FIG. 1, the liquid crystal display device 1 of the present embodiment has an STN (Super Twiste) in a space between a lower substrate 2 and an upper substrate 3 which are arranged to face each other.
d Nematic) A liquid crystal panel 1 which is roughly configured by sandwiching a liquid crystal 4 and a backlight (illumination device) 5 which is disposed on the rear surface side of the liquid crystal panel 1 (the outer surface side of the lower substrate 2). It has a general configuration.

On the inner surface side of the lower substrate 2 made of glass or resin, a lower reflective polarizing layer 6 (corresponding to the "reflective polarizing layer" in the claims) is laminated and formed on the lower reflective polarizing layer 6. Is provided so as to cover the surface of the lower reflective polarizing layer 6 on the liquid crystal 4 side, and is a stripe-shaped scanning electrode 8 made of a transparent conductive film such as ITO (corresponding to a "transparent electrode" in the claims). Extends in the direction perpendicular to the paper surface. An alignment film 9 made of polyimide or the like is laminated so as to cover the scan electrodes 8. In addition, the lower reflective polarizing layer 6 includes
A slit (opening) 10 for transmitting the light emitted from the backlight 5 is provided for each pixel. Further, a lower polarizing plate 20 and a reflective polarizing plate 21 are provided in this order on the outer surface side of the lower substrate 2.

On the other hand, the upper substrate 3 made of glass or resin
Red, green and blue color filters 11 extend in the direction perpendicular to the plane of the drawing so as to be orthogonal to the scanning electrodes 8 of the lower substrate 2, and are repeatedly arranged in this order on the inner surface side of the above. A flattening film 12 for flattening the unevenness formed by the color filter 11 is laminated. A stripe-shaped signal electrode 14 made of a transparent conductive film such as ITO extends in the horizontal direction on the flattening film 12, and an alignment film 15 made of polyimide or the like is laminated and formed on the scanning electrode 14. ing. Further, on the outer surface side of the upper substrate 3, the front scattering plate 16, the phase difference plate 17, and the upper polarizing plate 13 are provided.
Are laminated on the upper substrate 3 in this order. On the lower surface side of the backlight 5 (the side opposite to the liquid crystal panel 1),
A reflector 18 is provided.

The lower reflective polarization layer 6 is, as shown in FIG. 2, a metal reflective film 71 made of aluminum or aluminum alloy.
In addition, a plurality of slits 72 are formed at a predetermined pitch. In the present embodiment, the direction of the slit-shaped opening is substantially parallel to the transmission axis of the lower polarizing plate 20, that is,
The slits 72 are arranged so that the length direction of the slits 72 is parallel to the paper surface of FIG. The transmission axis of the lower reflective polarizing layer 6 and the transmission axis of the lower polarizing plate 20 are arranged so as to be substantially orthogonal to each other. Thereby, the light transmitted through the lower reflective polarizing layer 6 in the reflective mode can be efficiently absorbed by the lower polarizing plate 20, so that the dark display in the reflective mode is darkened and the contrast of the liquid crystal display device is improved. You can

The plurality of slits 72 are parallel to each other, and the slit width Ps of each slit 72 is substantially the same. The size of each part is not particularly limited, but the film thickness d of the metal reflection film 71 is 100 to 400 n.
and the width Ps of the slit 72 is 30 nm to 3 nm.
And the width Pm of one metal reflection film 71 is about 00 nm.
Is about 30 nm to 300 nm. In such a lower reflective polarization layer 6, when light is incident from the upper side, the component parallel to the length direction of the slit 72 is reflected and the slit 7
The component perpendicular to the length direction of 2 is transmitted. That is, the light Et transmitted through the lower reflective polarization layer 6 becomes polarized light perpendicular to the slit 72, and the light Er reflected by the lower reflective polarization layer 6 is reflected.
Is polarized light parallel to the slit 72.

Next, the operation principle of the liquid crystal display device of this embodiment will be described. 3A and 3B are explanatory diagrams for explaining the operation principle of the liquid crystal display device of the present embodiment. FIG. 3A shows a transmission mode light path, and FIG. 3B shows a reflection mode light path. In these figures, among the constituent elements of the liquid crystal display device of the present embodiment, only constituent elements necessary for explanation are shown. The upper polarizing plate 13 has a transmission axis perpendicular to the paper surface, and the lower polarizing layer 20 has a transmission axis parallel to the paper surface. The lower reflective polarization layer 6 has a transmission axis in a direction perpendicular to the paper surface and a reflection axis parallel to the paper surface.

The case of displaying in the transmissive mode shown in FIG. 3A will be described below. First, focusing on the light that is used for display and that passes through the opening 10, the light emitted from the illumination device 5 is converted into polarized light parallel to the paper surface by the lower polarization layer 20 having a transmission axis parallel to the paper surface. It is converted and passes through the opening 10 to enter the liquid crystal 4. At this time, if a voltage is applied to the liquid crystal 4 (ON state), the light incident on the liquid crystal 4 reaches the upper polarizing plate 13 with almost no effect of the liquid crystal 4 and is transmitted perpendicularly to the paper surface. It is absorbed by the upper polarizing plate 13 having an axis. In this way, the pixels are darkly displayed. On the other hand, when no voltage is applied to the liquid crystal 4 (off state), the light incident on the liquid crystal 4 is converted into polarized light perpendicular to the paper surface by the optical rotation effect of the liquid crystal 4, and reaches the upper polarizing plate 13. And the upper polarizing plate 1
This light, which is polarized light parallel to the transmission axis of 3, is reflected by the upper polarization plate 13
, And pixels are displayed brightly.

Here, among the light transmitted through the lower polarizing layer 20, focusing on the light that does not pass through the opening 10 and is reflected on the back surface side (lower side) of the reflective polarizing layer 6, this light is reflected. The light is reflected by the polarizing layer 6 and travels downward, and the lower polarizing layer 20
Is transmitted to the illuminating device 5, is reflected by the reflection plate 18 on the outer surface side of the illuminating device 5, and is reused as light traveling toward the lower polarizing layer 20 again. Then, this light is reflected by the reflective polarization layer 6
While the reflection is repeated between the reflection plate 18 and the reflection plate 18, the opening 10
And is used as light that contributes to the display. Therefore, in the liquid crystal display device of the present embodiment, the lighting device 5
Since the light emitted from is not absorbed by the lower polarization layer 20, the utilization efficiency of the light emitted from the illumination device 5 is high and a bright display can be obtained.

Next, the case of displaying in the reflection mode shown in FIG. 3B will be described. As shown in FIG. 3B, light incident from above the upper polarizing plate 13 is first converted into polarized light perpendicular to the paper surface by the upper polarizing plate 13 having a transmission axis perpendicular to the paper surface and then enters the liquid crystal 4. To do. Next, liquid crystal 4
Is ON, the incident light reaches the lower reflective polarization layer 6 with almost no effect of the liquid crystal 4. Since the lower reflection polarizing layer 6 has a transmission axis perpendicular to the paper surface and a reflection axis parallel to the paper surface, the light reaching the lower reflection polarizing layer 6 passes through the lower reflection polarization layer 6 and reaches the paper surface. It is absorbed by the lower polarizing plate 20 having parallel transmission axes. In this way, the pixels are darkly displayed. On the other hand, when the liquid crystal 4 is in the off state, the light incident on the liquid crystal 4 is converted into polarized light parallel to the paper surface by the optical rotation effect of the liquid crystal 4 and reaches the lower reflective polarization layer 6. Then, the light is reflected by the lower reflective polarization layer 6 having a reflection axis parallel to the paper surface, converted again into polarized light perpendicular to the paper surface by the optical rotation effect of the liquid crystal 4, and transmitted through the upper polarizing plate 13. In this way, the pixels are displayed brightly.

The liquid crystal display device of the present embodiment includes the lower reflective polarization layer 6 made of the metal reflective film 71, and the scanning electrode 8 provided so as to cover the surface of the lower reflective polarization layer 6 on the liquid crystal 4 side.
Since the lower reflective polarization layer 6 is in contact with the lower reflective polarization layer 6, the lower reflective polarization layer 6 can function as the scanning electrode 8.
Therefore, the function as the scanning electrode 8 can be supplemented by the lower reflective polarization layer 6, and the resistance value as the scanning electrode can be reduced. As a result, it is possible to prevent the inconvenience that the signal waveform is blunted and the display unevenness occurs due to the large resistance value of the scan electrode 8, and high quality display can be realized. Further, since the resistance value of the scan electrode can be reduced, the thickness of the scan electrode 8 can be reduced, the amount of the material forming the scan electrode 8 can be reduced, and the time required for manufacturing can be reduced. Can be shortened.

Further, in this embodiment, since the metal reflection film 71 constituting the lower reflection polarization layer 6 is made of aluminum or aluminum alloy, the adhesion to the lower substrate 2 made of glass or resin is used. Is sufficiently obtained. Further, since the lower reflective polarization layer 6 has a small resistance value, the function as the scanning electrode 8 can be effectively supplemented, and the resistance value as the scanning electrode can be made sufficiently small.

In the liquid crystal display device of the present embodiment, since the lower reflective polarizing layer 6 is formed inside the lower substrate 2, the quarter wave plate which is conventionally provided on the outer surface side of the lower substrate may be omitted. The display can be done. Therefore, conversion from linearly polarized light to circularly polarized light or from circularly polarized light to linearly polarized light does not occur, so there is no light loss accompanying these conversions. Therefore, it is possible to perform display with excellent visibility in both the reflection mode and the transmission mode. Particularly, in the transmission mode, since the quarter wave plate is not provided on the outer surface side of the lower substrate 2,
Of the light emitted from the backlight 5, the lower reflective polarization layer 6
The light reflected on the back surface side of and returned to the backlight 5 side can be reflected by the reflection plate 18 and returned to the liquid crystal panel 1 side again. Therefore, the light of the backlight 5 can be effectively used for the display, and the display brightness can be significantly improved as compared with the conventional case.

Further, in the liquid crystal display device of the present embodiment, the reflective polarizing plate 21 is provided on the outer surface side of the lower polarizing plate 20, so that of the light emitted from the backlight 5, the reflective polarizing plate 21 is not reflected. The component that is not parallel to the transmission axis is the reflective polarizing plate 2
1 is reflected and returned to the backlight 5 side, and the reflector plate 18
While the light is repeatedly reflected between and, the polarization state of the light changes and the light can be transmitted through the reflective polarizing plate 21 to become light that can be used for display. Therefore, in the liquid crystal display device of the present embodiment, since the lower polarizing plate 20 hardly absorbs the light, the light of the backlight 5 can be used more efficiently for the display, and the brightness of the display in the transmission mode can be improved. The liquid crystal display is excellent.

(Second Embodiment) In this embodiment, the overall structure of the liquid crystal display device is the same as that of the first embodiment shown in FIG. 1, and therefore detailed description thereof will be omitted. Further, the liquid crystal display device of the present embodiment is different from the liquid crystal display device of the first embodiment only in the lower reflective polarization layer and the scanning electrode. Therefore, referring to FIG. 4 for the lower reflective polarization layer and the scanning electrode. explain. FIG. 4 is a diagram showing a partial cross-sectional structure of the liquid crystal display device of the present embodiment, and FIG. 5 is a lower reflective polarization layer and a scanning electrode of the liquid crystal display device shown in FIG. 4, a scanning electrode and a liquid crystal driving element. FIG. 6 is a partial plan view showing the leading wiring and the wiring. In FIG. 4, the same components as those in FIG. 1 are designated by the same reference numerals.

As shown in FIG. 4, in the liquid crystal display device of this embodiment, unlike the liquid crystal display device of the first embodiment shown in FIG. 1, scan electrodes 81 are provided on the lower substrate 2. A lower reflective polarizing layer 61 made of silver or a silver alloy is provided on the scanning electrode 81. Unlike the liquid crystal display device of the first embodiment shown in FIG. 1, the direction of the slit-shaped opening forming the lower reflective polarization layer 61 is the extending direction of the scanning electrode 81 (the vertical direction in FIG. 5). Is almost parallel to.

Further, in the liquid crystal display device of this embodiment, as shown in FIG.
The transparent conductive film 82 formed at the same time, and the transparent conductive film 82
It is electrically connected to a terminal 80 connected to the liquid crystal driving element via a lead-out wiring formed on the metal film 62 formed on the lower reflection polarizing layer 61 at the same time.

The liquid crystal display device of the present embodiment has the scanning electrode 8
Since the lower reflective polarization layer 61 provided on the scanning electrode 81 is in contact with the first electrode 1, the lower reflective polarization layer 61 can function as the scanning electrode 81. Therefore, it is possible to realize high-quality display in which display unevenness due to the large resistance value of the scan electrode 81 is unlikely to occur, and to reduce the thickness of the scan electrode 81, which is the same effect as in the first embodiment. can get.

Moreover, in the liquid crystal display device of this embodiment, the lengthwise direction of the slit-shaped opening of the lower reflective polarization layer 61 is substantially parallel to the extending direction of the scanning electrodes 81 formed in stripes. Therefore, for example, the lower reflective polarization layer 61
A resistance value that is two orders of magnitude lower than that when the length direction of the slit-shaped opening is substantially orthogonal to the extending direction of the scanning electrode 81 is obtained. Therefore, the resistance value of the scanning electrode can be reduced more effectively.

Further, in the liquid crystal display device of the present embodiment, the lead wiring is composed of the transparent conductive film 82 and the transparent conductive film 8.
Since it is composed of the metal film 62 provided on the wiring 2, the function of the transparent conductive film 82 as the wiring can be supplemented by the metal film 62, and the resistance value of the wiring can be reduced. Therefore, the routing wiring can be made thin, and the space for arranging the routing wiring can be narrowed, so that the area of the frame region can be reduced.

Further, in the liquid crystal display device of the present embodiment, the transparent conductive film 82 is formed simultaneously with the scanning electrode 81, and the metal film 62 is formed simultaneously with the lower reflective polarization layer 61. The routing wiring can be easily formed.

Further, in the liquid crystal display device of this embodiment, the scanning electrode 8 is provided between the lower substrate 2 and the lower reflective polarization layer 61.
1, the lower substrate 2 is made of glass or resin, and the lower reflective polarizing layer 61 is made of silver or silver alloy having a high reflectance among metals. The scan electrode 81 formed of the transparent conductive film can sufficiently obtain the adhesiveness with the lower substrate 2 and the adhesiveness with the lower reflective polarization layer 61, and the adhesiveness between silver or a silver alloy and glass. Poor sex does not pose a problem.

Therefore, among metals, silver or silver alloy having a high reflectance and a low resistance can be preferably used as a material for forming the lower reflective polarizing layer 61. Therefore, the lower reflective polarizing layer 61 has a higher reflectance than when it is made of aluminum or an aluminum alloy.
As a result, light can be used for display more efficiently, and a brighter display can be realized in both the reflective mode and the transmissive mode.

In the liquid crystal display device of this embodiment, the transparent conductive film 8 such as ITO is also provided between the lower substrate 2 made of glass or resin and the metal film 62 made of silver or silver alloy.
2 is provided, there is no problem in that the adhesion between the lower substrate 2 made of glass or resin and the metal film 62 made of silver or silver alloy is not good.

Although the metal film 62 is provided on the transparent conductive film 82 in the liquid crystal display device of this embodiment, the metal film is provided in contact with at least a part of the transparent conductive film. The metal film may be formed on the lower substrate without interposing the transparent conductive film, and the transparent conductive film may be formed so as to cover the metal film, or the entire metal film may be transparent conductive. It may be covered with a film. Even in such a configuration, the function of the transparent conductive film as the routing wiring can be supplemented by the metal film, so that the resistance value of the routing wiring can be reduced. Further, in the liquid crystal display device of the present embodiment, the metal film 62 is formed at the same time as the lower reflective polarization layer 61, but the metal film 62 is the lower reflective polarization layer 61.
The metal film may not be formed at the same time, and the metal film may not be provided with the slit-shaped opening. In this case, the function of the transparent conductive film as the routing wiring can be more effectively supplemented by the metal film, and the resistance value of the routing wiring can be further reduced.

(Third Embodiment) In this embodiment, the overall structure of the liquid crystal display device is the same as that of the first embodiment shown in FIG. 1, and therefore detailed description thereof will be omitted. Further, the liquid crystal display device of the present embodiment is different from the liquid crystal display device of the first embodiment only in the lower reflective polarization layer and the scanning electrode. Therefore, referring to FIG. 6 for the lower reflective polarization layer and the scanning electrode. explain. FIG. 6 is a diagram showing a partial cross-sectional structure of the liquid crystal display device of the present embodiment. In FIG. 6, the same components as those in FIG. 1 are designated by the same reference numerals.

As shown in FIG. 6, in the liquid crystal display device of the present embodiment, unlike the liquid crystal display device of the first embodiment shown in FIG. 1, a lower reflective polarization layer 63 is formed on the lower substrate 2. To cover the liquid crystal side surface of the lower side and the lower reflective polarizing layer,
Scan electrodes 83 are provided.

Also in the liquid crystal display device of this embodiment, since the lower reflective polarization layer 63 is in contact with the scanning electrode 83, the lower reflective polarization layer 63 can function as the scanning electrode 83. Therefore, it is possible to realize high-quality display in which display unevenness due to the large resistance value of the scan electrode 83 is unlikely to occur, and to reduce the thickness of the scan electrode 83, which is the same effect as in the first embodiment. can get.

Further, in the liquid crystal display device of the present embodiment, the scanning electrode 83 is provided so as to cover the lower side of the lower reflective polarizing layer 63 made of silver or silver alloy and the surface of the lower reflective polarizing layer on the liquid crystal side. Therefore, the lower reflective polarization layer 63 in the process of forming the alignment film 9 which is a process after the lower reflective polarization layer 63 is formed.
The surface of is protected by the scanning electrode 83. Therefore, even if the lower reflective polarization layer 63 is made of silver or a silver alloy, unevenness is not formed on the surface of the lower reflective polarization layer 63 due to heat in the forming process of the alignment film 9. It is possible to prevent yellowing of the lower reflective polarizing layer 63 due to heat in the process of forming the alignment film 9,
High quality display can be realized.

The liquid crystal display device of the present invention is not limited to the liquid crystal display device of the above-mentioned embodiment. For example, the reflective polarizing layer and the transparent electrode are provided with the reflective polarizing layer and the reflective polarizing layer. Any shape may be used as long as at least a part of the transparent electrode provided on the same substrate as the existing substrate is in contact therewith.

Further, the liquid crystal display device of the present invention is not limited to the above-mentioned anti-transmissive reflection type liquid crystal display device, but can be applied to a transmission type or a reflection type liquid crystal display device.

(Electronic Equipment) Examples of electronic equipment equipped with the liquid crystal display device of each of the above-described embodiments will be described.

FIG. 7A is a perspective view showing an example of a mobile phone. In this figure, reference numeral 1000 indicates a mobile phone main body, and reference numeral 1001 indicates a liquid crystal display unit using the above liquid crystal display device.

FIG. 7B is a perspective view showing an example of a wrist watch type electronic device. In this figure, reference numeral 1100 indicates a watch body, and reference numeral 1101 indicates a liquid crystal display unit using the above liquid crystal display device.

FIG. 7C is a perspective view showing an example of a portable information processing device such as a word processor and a personal computer. Figure 7
In (c), reference numeral 1200 is an information processing device, reference numeral 1
Reference numeral 202 denotes an input unit such as a keyboard, reference numeral 1204 denotes an information processing apparatus main body, and reference numeral 1206 denotes a liquid crystal display unit using the above liquid crystal display device.

The electronic devices shown in FIGS. 7A to 7C are provided with the liquid crystal display section using the liquid crystal display device of the above-described embodiment, and therefore display unevenness hardly occurs and high quality display can be obtained. An electronic device having a liquid crystal display unit can be realized.

[0060]

As described above in detail, the liquid crystal display device of the present invention includes the reflective polarizing layer made of a metal reflective film as the polarizing layer, and at least a part of the reflective polarizing layer is in contact with the transparent electrode. Therefore, at least a part of the reflective polarizing layer can function as an electrode. Therefore, the function of the transparent electrode as an electrode can be supplemented by the reflective polarizing layer, and the resistance value of the electrode can be reduced. As a result, due to the large resistance of the transparent electrode,
It is possible to prevent the inconvenience that the signal waveform is blunted and display unevenness occurs, and high-quality display can be realized. Further, since the resistance value of the electrode can be reduced, the thickness of the transparent electrode can be reduced, the amount of the material forming the transparent electrode can be reduced, and the time required for manufacturing can be shortened. You can

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of a liquid crystal display device according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing an example of a lower reflective polarizing layer which constitutes the liquid crystal display device of the present invention.

3A and 3B are explanatory views for explaining the operation principle of the liquid crystal display device of the present invention, FIG. 3A shows a transmissive mode, and FIG. 3B shows a reflective mode. .

FIG. 4 is a partial cross-sectional view of a liquid crystal display device according to a second embodiment of the present invention.

5 is a partial plan view showing the lower reflective polarizing layer and the scanning electrode of the liquid crystal display device shown in FIG. 4, and the leading wiring between the scanning electrode and the liquid crystal driving element.

FIG. 6 is a partial cross-sectional view of the liquid crystal display device according to the first embodiment of the present invention.

7 (a) to 7 (c) are perspective views showing an example of an electronic apparatus of the present invention.

FIG. 8 is a partial cross-sectional view showing an example of a conventional liquid crystal display device.

[Explanation of symbols]

1 Liquid crystal display 2 Lower substrate 3 Upper substrate 4 liquid crystal 5 Backlight (illumination device) 6 Lower reflective polarizing layer 11 color filters 13 Upper polarizing plate (upper polarizing layer) 20 Lower polarizing plate (lower polarizing layer) 6, 61, 63 Lower reflective polarizing layer (reflective polarizing layer) 8, 81, 83 Scanning electrodes (transparent electrodes) 62 metal film 82 Transparent conductive film

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G09F 9/30 338 G09F 9/30 338 9/35 9/35 F term (reference) 2H049 BA02 BA45 BB03 BC01 BC22 2H091 FA07 FA14 FA41 FB08 FD22 GA03 LA11 LA17 2H092 GA05 GA13 GA17 NA01 NA28 PA11 PA13 5C094 AA03 AA15 BA03 BA43 CA19 EA04 EA05 EA07

Claims (10)

[Claims] 1. A liquid crystal display device in which liquid crystal is sandwiched between an upper substrate and a lower substrate facing each other, and a transparent electrode and a polarizing layer are provided on the upper substrate and the lower substrate, respectively. The polarizing layer provided on at least one of the substrate and the lower substrate comprises a reflective polarizing layer in which a plurality of fine slit-shaped openings are provided in a metal reflective film, and the reflective polarizing layer is the reflective polarized light. At least a part of the liquid crystal display device is in contact with the transparent electrode provided on the same substrate on which the layer is provided. 2. A transflective liquid crystal display device, wherein an illuminating device is provided on an outer surface side of the lower substrate, and a display is performed by switching between a transmissive mode and a reflective mode, wherein the reflective polarizing layer is provided on the lower substrate. The liquid crystal display device according to claim 1, further comprising: 3. The transparent electrode provided on the substrate provided with the reflective polarizing layer is provided so as to cover the surface of the reflective polarizing layer on the liquid crystal side. Alternatively, the liquid crystal display device according to claim 2. 4. The transparent electrode is provided on a substrate provided with the reflective polarizing layer, and the reflective polarizing layer is provided on the transparent electrode. The liquid crystal display device according to any one of 1. 5. The liquid crystal display device according to claim 1, wherein the reflective polarizing layer is made of silver or a silver alloy. 6. The transparent electrode provided on a substrate provided with the reflective polarizing layer is formed in a stripe shape, and the transparent portion is formed in a stripe shape in a length direction of the slit-shaped opening. The electrode is substantially parallel to the extending direction of the electrode.
The liquid crystal display device according to item. 7. A lead-out wiring for electrically connecting the transparent electrode and the liquid crystal driving element is provided, and the lead-out wiring is provided so that at least a part of the transparent conductive film is in contact with the transparent conductive film. 7. A metal film according to any one of claims 1 to 6, characterized in that
The liquid crystal display device according to item. 8. A substrate provided with the metal film,
The liquid crystal display device according to claim 7, wherein the transparent conductive film is provided, and the metal film is provided on the transparent conductive film. 9. The liquid crystal display device according to claim 7, wherein the metal film is a metal reflection film provided with a plurality of fine slit-shaped openings. 10. The method according to any one of claims 1 to 9.
An electronic device comprising the liquid crystal display device according to item.