JP2000066199A - Liquid crystal device and electronic equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a picture display with high quality both in a reflection mode display and in a transmission mode display, with a comparatively simple device constitution and without generating any double image due to parallax or blotting of image in a liquid crystal device which is convertible between the reflection mode display and in the transmission mode display. SOLUTION: When a backlight 218 is turned on in dark surroundings a light from a light source passes through gaps between reflection layers 216 via a polarizing plate 208 or the like to realize a transmission display. An incident external light via a polarizing plate 205 or the like in bright surroundings is reflected on the reflection layers 216 to realize a reflective display. On the reflection layers 216 transparent electrodes 215 with sizes a little larger than theirs are formed and the light from the light source which passes through gaps between reflection layers 216 is transmitted through parts of the transparent electrodes 215 swollen out from the reflection layers 216.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of a liquid crystal device, and more particularly, to a liquid crystal device capable of switching and displaying a reflection type display and a transmission type display, and a technique of an electronic apparatus using the liquid crystal device. Belongs to the field.

[0002]

2. Description of the Related Art Conventionally, reflection type liquid crystal devices have been frequently used for portable devices and auxiliary display units of the devices due to low power consumption. However, since the display is made visible using external light, the reflection type liquid crystal device is dark. There was a problem that the display could not be read at the place. For this reason, there has been proposed a liquid crystal device of a type in which external light is used in a bright place similarly to a normal reflection type liquid crystal device, but in a dark place, the display can be visually recognized by an internal light source. In this configuration, as described in Japanese Utility Model Laid-Open No. 57-049271, a polarizing plate, a transflective plate, and a backlight are sequentially arranged on the outer surface of the liquid crystal panel opposite to the observation side. In this liquid crystal device, when the surroundings are bright, external light is taken in and reflective display is performed using light reflected by the semi-transmissive reflecting plate. When the surroundings are dark, the backlight is turned on and the semi-transmissive reflecting plate is turned on. A transmissive display in which the display can be visually recognized by the light transmitted through is provided.

As another liquid crystal device, there is one disclosed in Japanese Patent Application Laid-Open No. Hei 8-292413 in which the brightness of a reflective display is improved. This liquid crystal device has a configuration in which a transflective plate, a polarizing plate, and a backlight are sequentially arranged on the outer surface of the liquid crystal panel opposite to the observation side. When the surroundings are bright, external light is taken in and reflective display is performed using the light reflected by the semi-transmissive reflector. When the surroundings are dark, the backlight is turned on and the polarizing plate and the semi-transmissive reflector are transmitted. A transmissive display in which the display is visually recognizable by the applied light is performed. With such a configuration, since there is no polarizing plate between the liquid crystal cell and the transflective plate, a reflective display brighter than the above-described liquid crystal device can be obtained.

[0004]

However, in the liquid crystal device described in JP-A-8-292413, since a transparent substrate is interposed between the liquid crystal layer and the transflective plate, double reflection or display is not possible. There is a problem that blurring occurs.

Further, with the development of portable equipment and OA equipment in recent years, colorization of liquid crystal display has been required, and there are cases where colorization is necessary even in equipment using a reflection type liquid crystal device. Many. However, in the method in which the liquid crystal device and the color filter described in the above publication are combined, the transflective plate is disposed behind the liquid crystal panel. There is a problem in that a thick transparent substrate of the liquid crystal panel is interposed, and a double reflection or blurring of display occurs due to parallax, so that sufficient coloring cannot be obtained.

To solve this problem, Japanese Patent Laid-Open No. 9-2
Japanese Patent No. 58219 proposes a reflective color liquid crystal device in which a reflector is arranged so as to be in contact with a liquid crystal layer. However, in this liquid crystal device, when the surroundings are dark, the display cannot be recognized.

On the other hand, Japanese Patent Application Laid-Open No. Hei 7-318929 proposes a transflective liquid crystal device in which a pixel electrode serving also as a transflective film is provided on the inner surface of a liquid crystal cell. Also, ITO (Indium Tin) is formed on a semi-transmissive reflective film made of a metal film.
Oxide) is disclosed in which a transparent pixel electrode made of a film is stacked via an insulating film. However, in this liquid crystal device, a hole defect or a defect occurs with respect to a pixel electrode which also serves as a transflective film or a transflective film on which a transparent pixel electrode is superimposed.
Since it is necessary to provide a large number of fine defects such as dent defects and fine openings, the structure of the device becomes complicated, and a special process is additionally required in the manufacture thereof. It is difficult to manufacture a transflective film.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems. In a liquid crystal device capable of switching between a reflective display and a transmissive display, a double image due to parallax is produced by using a relatively simple device configuration. Uses a transflective liquid crystal device with high display quality in both reflective and transmissive displays without causing display bleeding, etc. It is an object to provide an electronic device that has been used.

[0009]

According to the present invention, there is provided a liquid crystal device comprising: a pair of transparent first and second substrates; and a liquid crystal layer sandwiched between the first and second substrates. A plurality of reflective layers formed on a surface of the second substrate on the liquid crystal layer side, the plurality of reflective layers being separated from each other when viewed two-dimensionally from a direction perpendicular to the second substrate; A transparent electrode including a portion that is formed to partially overlap and does not overlap the reflective layer when viewed in plan; and a lighting device disposed on the second substrate on the side opposite to the liquid crystal layer.

According to the liquid crystal device of the present invention, at the time of the reflection type display, the external light incident from the first substrate side is reflected toward the liquid crystal layer side by the reflection layer. At this time, since the reflective layer is disposed on the liquid crystal layer side of the second substrate, there is almost no gap between the reflective layer and the liquid crystal layer, and therefore, double reflection of display and display bleeding due to parallax are caused. Does not occur. On the other hand, at the time of the transmissive display, the light source light emitted from the illumination device and incident from the second substrate side is transmitted to the liquid crystal layer side through the gap between the reflective layers and the transparent electrode. Therefore, a bright display can be performed in a dark place using the light from the light source.

In the liquid crystal device of the present invention, in particular, the external light reflected on the reflection area (non-transmission area) where the transparent electrode overlaps on the reflection layer reflects the liquid crystal part driven by the transparent electrode part in the reflection area. pass. That is, a reflective display can be performed using a liquid crystal portion driven by a vertical electric field by a transparent electrode portion in the reflection region. On the other hand, the light source light emitted from the lighting device and transmitted through the transmission region (non-reflection region) corresponding to the gap of the reflection layer passes through the transparent electrode portion not overlapping the reflection layer, and is transmitted by the transparent electrode portion in the transmission region. It passes through the driven liquid crystal part. That is, transmissive display can be performed using a liquid crystal portion driven by a vertical electric field by a transparent electrode portion in the transmission region. As described above, the liquid crystal drive during the reflective display is performed using the transparent electrode portion overlapping the reflective layer, and the liquid crystal drive during the transmissive display is performed using the transparent electrode portion not overlapping the reflective layer. It is possible to drive the liquid crystal satisfactorily by the vertical electric field even during the display of the type (1), the liquid crystal alignment direction becomes uniform in each dot or each pixel, and it is possible to prevent the deterioration of the display quality due to the disorder of the alignment direction. . Note that a portion of the reflective layer where the transparent electrodes do not overlap does not contribute to display (that is, lowers the contrast ratio), and is basically unnecessary, and from the viewpoint of effective use of a limited image display area, It is preferable to lay out the reflective layer portion where the transparent electrode does not overlap so as not to provide the reflective layer portion.

Further, in the liquid crystal device according to the present invention, a hole defect, a dent defect, etc., may be caused with respect to a pixel electrode which also functions as a transflective film as in the above-mentioned conventional example or a transflective film on which a transparent pixel electrode is superimposed. Since there is no need to provide a large number of fine defects and fine openings, the configuration of the device does not become complicated, and no special process is additionally required in its manufacture. As a result, a laminated structure in which the transparent electrode is laminated on the reliable reflective layer can be constructed,
Finally, using a relatively simple device configuration, a liquid crystal device that can display high-quality images in both the reflective display mode and the transmissive display mode and has high device reliability is realized.

As a material of such a reflective layer, Al is used.
(Aluminum) is used as the main component, but Cr
The material is not particularly limited as long as it is a metal such as (chromium) or Ag (silver) that can reflect external light in the visible light region.

As a driving method of the liquid crystal device of the present invention, a passive matrix driving method, a TFT (Thin Film Transi
stor) active matrix drive system, TFD (Thin F
Various known driving methods such as an active matrix driving method and a segment driving method can be adopted. At this time, in the reflective display and the transmissive display, the voltage of the liquid crystal cell −
Since the reflectance (transmittance) characteristics often differ, it is preferable to make the drive voltage different between the reflective display mode and the transmissive display mode, and to optimize each of them. Further, on the first substrate, a plurality of stripe-shaped or segment-shaped transparent electrodes are formed as appropriate according to the driving method, or a transparent electrode is formed on almost the entire surface of the first substrate. Alternatively, the driving may be performed by a horizontal electric field parallel to the substrate between the transparent electrodes on the second substrate without providing the counter electrode on the first substrate. Further, in the liquid crystal device, a polarizing plate, a retardation plate, and the like are respectively disposed on the first substrate and the second substrate on the side opposite to the liquid crystal layer according to the display method.

In one aspect of the liquid crystal device of the present invention, the transparent electrode is formed such that its area is larger than the area of the reflective layer.

According to this aspect, since the transparent electrode is larger than the reflective layer in a plan view, the transparent electrode portion on which the reflective layer contributing to the reflective display is superimposed or the reflective layer contributing to the transmissive display is superposed. At the same time, the ratio of the transparent electrode portion not occupied in the image display region can be efficiently increased, and at the same time, the ratio of the reflection layer portion not overlapping the transmission electrode that does not contribute to either of these types of display to the image display region is reduced. Can be reduced.

For example, when viewed two-dimensionally, it is also possible to form a small reflective layer near one side of a large transparent electrode. With this configuration, the liquid crystal portion through which the external light reflected by the reflective layer passes can be driven by the vertical electric field during reflective display by the transparent electrode portion on the side where the reflective layer overlaps. Further, by the transparent electrode portion on the side where the reflective layer does not overlap, it is possible to drive the liquid crystal portion through which the light source light passing through the transparent electrode portion passes by the vertical electric field during the transmissive display.

For example, if the transparent electrode is formed to be slightly larger than the reflective layer when viewed two-dimensionally, it is reflected by the reflective layer during reflective display by the transparent electrode portion near the center where the reflective layer is superimposed. The liquid crystal portion through which external light passes can be driven by the vertical electric field. Further, the liquid crystal portion through which the light source light passing through the transparent electrode portion passes can be driven by the vertical electric field during the transmissive display by the transparent electrode portion near the periphery where the reflective layer does not overlap.

In another aspect of the liquid crystal device of the present invention, the transparent electrode and the reflective layer are formed in a stripe shape.

According to this aspect, when viewed in a plan view, a reflective display can be performed by the stripe-shaped transparent electrode portions superposed on the stripe-shaped reflection layer, and one side or both sides of the stripe-shaped reflection layer can be displayed. Transmissive display can be performed by the striped transparent electrode portions that do not overlap. Therefore, for example, in a liquid crystal device of a simple matrix drive system, reflective display and transmissive display can be performed with high quality using a relatively simple configuration.

In another aspect of the liquid crystal device of the present invention, the transparent electrode and the reflective layer are formed in an island shape.

According to this aspect, in a plan view, the reflective display can be performed by the island-shaped transparent electrode portion which is superimposed on the island-shaped reflection layer at the center or on one side. Transmissive display can be performed by a transparent electrode portion that does not overlap around the periphery. Therefore, for example, in a liquid crystal device of an active matrix drive system, reflective display and transmissive display can be performed with high quality using a relatively simple configuration.

In another aspect of the liquid crystal device of the present invention, the transparent electrode is formed directly on the reflective layer.

According to this aspect, since the transparent electrode is formed directly on the reflective layer, both are electrically connected. For this reason, by forming the reflective layer from a conductive material such as Al, each of the stripe-shaped or island-shaped reflective layers can function as a redundant structure of the corresponding transparent electrode, and a low resistance as an electrode of the transparent electrode can be obtained. Or the resistance of the wiring can be reduced. On the other hand, if the reflective layer is made of an insulating material, the outer reflective layer can also have a function of insulating the transparent electrode from other layers and a function of protecting the transparent electrode, thereby simplifying the entire laminated structure. It becomes possible.

In another aspect of the liquid crystal device of the present invention, the transparent electrode is formed on the reflective layer via at least one of an insulating film, a color filter, and a protective film.

According to this aspect, for example, the reflective layer, the color filter, the protective film, and the transparent electrode are arranged in this order from the side closer to the second substrate, or the reflective layer, the insulating film, the color filter,
The protective film and the transparent electrode are laminated in this order. Or the second
The reflective layer, the insulating film, and the transparent electrode are stacked in this order from the side closer to the substrate. In this case, a color filter and a protective film may be formed on the liquid crystal layer side surface of the first substrate.

In particular, if a color filter is formed on the reflection layer, a reflection type color display using external light and a transmission type color display using an illumination device can be performed. It is preferable that the color filter has a transmittance of 25% or more for all light in a wavelength range of 380 nm to 780 nm. By doing so, bright reflective color display and transmissive color display can be realized.

Normally, a metal mainly composed of Al is used for the reflective layer. However, Al metal is very difficult to handle due to weak solvent resistance and is easily scratched. Therefore, the reflective surface of the reflective layer such as Al metal is covered with a protective film or an insulating film so that Al does not directly come into contact with a developer for forming a transparent electrode such as an ITO film or a developer for forming a color filter. Good to do. For such a protective film, a material such as an acrylic transparent resin or silicon oxide can be used.

Further, if a transparent electrode is formed on an insulating film,
The transparent electrode and its underlying layer can be reliably insulated.

In another aspect of the liquid crystal device of the present invention, the transparent electrode is formed on the reflective layer via an insulating film, and the insulating film is formed by oxidizing a surface portion of the reflective layer. .

According to this embodiment, an extremely thin insulating film having high insulating properties can be obtained. In this case, it is preferable to use aluminum as the reflective layer. This is because aluminum can maintain its reflectance even if it is oxidized. still,
When oxidizing the insulating film in this manner, the reflective layer may be anodized or thermally oxidized.

According to this aspect, the insulating film has two different layers.
It may be formed by laminating more than two kinds of insulating films.

With this configuration, the insulating property of the insulating film can be improved. Incidentally, an oxide of aluminum or the like is used as one insulating film, and SiO 2 is used as the other insulating film.
_{2 A} (silicon oxide) film, an overcoat film made of an organic substance, or the like can be used. When forming the SiO ₂ film, it may be formed by vapor deposition, sputtering or CVD.
When an organic film is formed, it may be formed by spin coating or the like.

In another embodiment of the liquid crystal device of the present invention, the non-driving state is a dark (black) state.

According to this aspect, since the non-driving state is a dark state, it is possible to suppress light leakage from between pixels or dots where the liquid crystal is not driven during the transmissive display, and to achieve a transmissive display with higher contrast. Obtainable. Also,
At the time of the reflection type display, reflected light unnecessary for display between pixels or between dots can be suppressed, so that a display with higher contrast can be obtained. As described above, it is possible to improve the contrast at the time of transmissive display and at the time of reflective display without providing a light-shielding film generally called a black matrix or a black mask at a position facing the gap between the reflective electrodes. In addition, by providing such a light-shielding film, it is possible to prevent a situation in which the brightness at the time of reflective display is reduced.

In another aspect of the liquid crystal device of the present invention, the reflective layer contains 95% by weight or more of Al and has a layer thickness of 10%.
nm or more and 40 nm or less.

According to this aspect, good reflectivity can be obtained by the relatively thin reflecting layer, and at the same time, each reflecting layer can be separated well. Experiments show that within this layer thickness range, the reflectivity is 5
The reflective layer can be manufactured so that the transmittance is 0% or more and 95% or less and the transmittance of the gap is 1% or more and 40% or less.

In another aspect of the liquid crystal device of the present invention, the reflection layer has irregularities.

According to this aspect, the mirror feeling of the reflection layer can be eliminated by the unevenness, and the reflection layer can be seen as a scattering surface (white surface). In addition, a display with a wide viewing angle can be performed by scattering due to unevenness. This uneven shape can be formed by using a photosensitive acrylic resin or the like for the base of the reflective layer, or by roughening the base glass substrate itself with hydrofluoric acid. In addition, it is desirable to further form a transparent flattening film on the uneven surface of the reflective layer and to flatten the surface facing the liquid crystal layer (the surface on which the alignment film is formed) from the viewpoint of preventing poor alignment of the liquid crystal. .

An electronic apparatus according to the present invention includes the above-described liquid crystal device according to the present invention in order to solve the above problems.

According to the electronic apparatus of the present invention, the display can be switched between the reflective display and the transmissive display by using a relatively simple apparatus configuration without causing double reflection due to parallax or blurring of the display. Various electronic devices using a transflective liquid crystal device or a transflective color liquid crystal device with high device reliability can be realized.

The operation and other advantages of the present invention will become more apparent from the embodiments explained below.

[0043]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) A first embodiment of the liquid crystal device according to the present invention will be described with reference to FIGS. FIG.
1 is a schematic vertical sectional view showing a structure of a first embodiment of a liquid crystal device according to the present invention. Although this embodiment is basically related to a simple matrix type liquid crystal display device, it can be applied to an active matrix type device, another segment type device, and other liquid crystal devices with the same configuration. .

In FIG. 1, in the liquid crystal device of the first embodiment, a liquid crystal layer 20 is disposed between two transparent substrates 201 and 202.
A liquid crystal cell 3 is sealed with a frame-shaped sealing material 204. The liquid crystal layer 203 is made of a nematic liquid crystal having a predetermined twist angle. A color filter 213 is formed on the inner surface of the upper transparent substrate 201. The color filter 213 has R (red), G
Three colored layers (green) and B (blue) are arranged in a predetermined pattern. A transparent protective film 212 is coated on the surface of the color filter 213, and a plurality of stripe-shaped transparent electrodes 211 are formed on the surface of the protective film 212 by ITO.
(Indium Tin Oxide) film. An alignment film 210 is formed on the surface of the transparent electrode 211, and rubbing is performed in a predetermined direction.

On the other hand, on the inner surface of the lower transparent substrate 202, on the stripe-shaped reflective layer 216 formed for each color layer of the color filter 213, a stripe-shaped transparent layer having a larger area than the reflective layer 216 is formed. A plurality of electrodes 215 are arranged so as to intersect the transparent electrodes 211.

In the case of an active matrix type device provided with a TFD element and a TFT element, each transparent electrode 215 is formed in a rectangular shape and is connected to a wiring via the active element.

The reflection layer 216 is formed of Cr, Al, or the like, and its surface is a reflection surface for reflecting light incident from the transparent substrate 201 side. An alignment film 214 is formed on the surface of the transparent electrode 215, and is rubbed in a predetermined direction.

As described above, in the first embodiment, each gap between the plurality of reflective layers 216 arranged in a stripe pattern at a predetermined interval has a function of transmitting light from the backlight. The interval between such reflective layers 216 is 0.01 μm
It is preferably at least 20 μm. By doing so, it is difficult for humans to recognize, and it is possible to suppress deterioration in display quality caused by providing the gap,
Reflective display and transmissive display can be realized simultaneously. The gap between the reflective layer 216 and the reflective layer 216 is 5% or more and 3% or more.
It is preferable to form them at an area ratio of 0% or less. By doing so, it is possible to suppress a decrease in the brightness of the reflective display, and it is possible to realize a transmissive display by light source light introduced into the liquid crystal layer from the gap between the reflective layers.

Here, an electric field applied to the liquid crystal layer 203 by the transparent electrode 215 laminated on the reflective layer 216 in the first embodiment will be described with reference to FIG. FIG. 2A shows a fine (for example, 2 μm diameter) opening 216.
In the comparative example using the transflective electrode 216 ′ having a single-layer structure which also functions as the transflective layer provided with a ′ and the pixel electrode, the state of the electric field applied to the liquid crystal layer by the transflective electrode 216 ′ It is the conceptual diagram which showed typically. FIG.
(B) is a conceptual diagram schematically showing a state of an electric field applied to the liquid crystal layer by the transparent electrode 215 laminated on the reflective layer 216 in the first embodiment.

As shown in FIG. 2A, when the transflective electrode 216 'made of a single conductive layer is used in the comparative example, the light is reflected in the non-transmissive area except for the transmissive area At during reflective display. The liquid crystal portion through which the external light passes passes through the semi-transmissive reflective electrode 216 ′ in the non-transmissive region to generate the vertical electric field Fr.
(Electric field in a direction perpendicular to the substrate). However, at the time of transmissive display, the liquid crystal portion in the transmissive region At through which the light source light entering from the opening 216a 'of the transflective electrode 216' passes obliquely by the transflective electrode 216 'portion in the non-transmissive region. It must be driven by the electric field Ft '. That is, at the time of transmissive display, display is performed by driving the liquid crystal by the distorted electric field in the transmissive region At, so that the display quality is deteriorated due to disturbance of liquid crystal alignment as compared with the case of driving the liquid crystal by the vertical electric field.

As shown in FIG. 2B, the first
In the embodiment, when the one-size-larger transparent electrode 215 laminated on the divided reflective layer 216 is used, at the time of the reflective display, it can be driven by the vertical electric field Fr by the transparent electrode 215 overlapping the reflective layer 216. . Moreover,
Also in the transmissive display mode, the liquid crystal portion in the transmission region At where the light source light incident from the gap of the reflective layer 216 passes can be driven by the vertical electric field Ft by the transparent electrode 215 facing the gap of the reflective layer 216. As described above, since the electric field applied to the liquid crystal layer by the transparent electrode 215 is not affected irrespective of the pattern of the reflective layer 216, the vertical voltage applied from the transparent electrode 215 is independent of the gap pattern in the reflective layer 216. Due to the electric field, the alignment direction of the liquid crystal becomes uniform in each dot or each pixel, and it is possible to prevent the display quality from deteriorating due to the disorder in the alignment direction.

Referring again to FIG. 1, the upper transparent substrate 201
A polarizing plate 205 is disposed on the outer surface of the substrate, and a retardation plate 206 and a scattering plate 207 are provided between the polarizing plate 205 and the transparent substrate 201.
Are arranged respectively. Further, a retardation plate 209 is disposed behind the transparent substrate 202 below the liquid crystal cell, and a polarizing plate 208 is disposed behind the retardation plate 209. A backlight having a fluorescent tube 218 that emits white light and a light guide plate 217 having an incident end face along the fluorescent tube 218 is disposed below the polarizing plate 208. The light guide plate 217 is a transparent body such as an acrylic resin plate on which a rough surface for scattering is formed on the entire back surface or a printed layer for scattering is formed.
Is received at the end face, and substantially uniform light is emitted from the upper surface of the drawing. As another backlight, an LED (light emitting diode), an EL (electroluminescence), or the like can be used.

On the other hand, the scattering plate 207 has an Al reflecting layer 216.
Thus, the reflected light reflected by the reflecting layer 216 can be emitted at a wide angle, and the mirror effect of the reflecting layer 216 can be made to look like a scattering surface (white surface) by the scattering plate 207. The scattering plate 20
The position of 7 may be any position as long as it is on the opposite side of the transparent substrate 201 from the liquid crystal layer 203. Scattering plate 20
Considering the effect of back scattering (scattering on the incident light side when external light enters) of the polarizing plate 20 as in the present embodiment,
5 and the transparent substrate 201. Backscattering is scattered light that is irrelevant to the display of the liquid crystal device, and the presence of this backscattering reduces the contrast during reflective display. By disposing it between the polarizing plate 205 and the transparent substrate 201, the amount of backscattered light can be reduced.
05 can reduce it by about half.

As described above, in the first embodiment, the polarizing plate 205 and the retardation plate 206 are disposed above the liquid crystal cell, and the polarizing plate 208 and the retardation plate 209 are disposed below the liquid crystal cell.
, Good display control can be performed in both the reflective display and the transmissive display. More specifically, the phase difference plate 206 reduces the influence on the color tone such as coloring caused by the wavelength dispersion of light in the reflection type display (that is, the display in the reflection type display using the phase difference plate 206). In addition, the phase difference plate 209 reduces the influence on the color tone such as coloring caused by the wavelength dispersion of light in the transmission type display (that is, the phase difference plate 206 optimizes the display in the reflection type display). Under such conditions, the phase difference plate 209 can further optimize the display at the time of transmissive display). It is also possible to arrange a plurality of retardation plates 206 and 209 by color compensation of a liquid crystal cell or visual angle compensation, respectively. Thus, the retardation plate 206 or 20
Ninth, optimization of coloring compensation or viewing angle compensation can be more easily performed by using a plurality of retardation plates. Furthermore, the polarizing plate 205, the retardation plate 106, the liquid crystal layer 103, and the reflection layer 21
6 are set to enhance the contrast during the reflective display, and the polarizing plate 20 is set under this condition.
8 and the optical characteristics of the phase difference plate 209 are set so as to increase the contrast at the time of transmission type display.
High contrast characteristics can be obtained in both the reflective display and the transmissive display.

Next, with reference to FIG. 1, a description will be given of the reflective display and the transmissive display in the present embodiment configured as described above.

First, in the case of the reflection type display, external light entering the liquid crystal device from the upper side of the figure is divided into a polarizing plate 205 and a retardation plate 2.
After passing through the color filter 06 and the scattering plate 207, pass through the color filter 213 and the liquid crystal layer 203, are reflected by the reflection layer 216, and are again emitted from the polarizing plate 205. At this time, the bright state, the dark state, and the intermediate brightness can be controlled by the voltage applied to the liquid crystal layer 203.

In the case of the transmissive display, light from the backlight is converted into predetermined polarized light by the polarizing plate 208 and the phase difference plate 209, and is introduced into the liquid crystal layer 203 and the color filter 213 from a gap where the reflective layer 216 is not formed. Then, the light passes through the scattering plate 207 and the phase difference plate 206. At this time, depending on the voltage applied to the liquid crystal layer 203, the polarizing plate 205 is transmitted (bright state) and absorbed (dark state).
And the intermediate state (brightness) can be controlled.

Here, regarding the reflection type display and the transmission type display,
This will be described in more detail with reference to FIGS. FIG.
1 is a schematic front view of a lower transparent substrate 202 when the present invention is applied to an active matrix type liquid crystal device using an FD element. A TFD element (or MIM element) 502 connected to the scanning line 501 is laminated on the island-shaped Al reflective layer 503, and is formed on the island-shaped ITO transparent electrode 504 having an area slightly larger than the Al reflective layer 503. It is connected.
In FIG. 3, the ITO transparent electrode 504 is not formed so as to completely cover the Al reflective layer 503, but, of course, the ITO transparent electrode 504 is
03 may be completely formed.
If the ITO transparent electrode 504 is formed so as to completely cover the Al reflective layer 503, more light from the backlight can be transmitted to the liquid crystal layer, so that a brighter transmissive display is realized. FIG. 4 is a schematic front view of an example of the lower transparent substrate 202 when the present invention is applied to a simple matrix type liquid crystal device. Striped ITO transparent electrode 601 formed on the inner surface of the upper transparent substrate of the liquid crystal cell
The Al reflection layer 60 is formed on the inner surface of the lower transparent substrate so as to cross
An ITO transparent electrode 603 in the form of a stripe having an area slightly larger than that of the second and Al reflective layers 602 is formed. still,
In FIG. 4, the ITO transparent electrode 603 is not formed so as to completely cover the Al reflective layer 602, but, of course, the ITO transparent electrode 603 may be formed so as to completely cover the Al reflective layer 602. I do not care. If the ITO transparent electrode 603 is formed so as to completely cover the Al reflective layer 602, more light from the backlight can be transmitted to the liquid crystal layer, so that a brighter transmissive display is realized. FIG. 5 is a schematic front view of another example of the lower transparent substrate 202 when the present invention is applied to a simple matrix type liquid crystal device. A stripe shape having a width that is slightly wider than each side of the island-shaped Al reflective layer 602 ′ on the inner surface of the lower transparent substrate so as to intersect with the stripe-shaped ITO transparent electrode 601 formed on the inner surface of the upper transparent substrate of the liquid crystal cell. I
A TO transparent electrode 603 is formed. FIG. 6
FIG. 7 is a schematic front view of another example of the lower transparent substrate 202 when the present invention is applied to a simple matrix type liquid crystal device. The Al reflective layer 602 ″ and the Al reflective layer 60 are formed on the inner surface of the lower transparent substrate so as to intersect the stripe-shaped ITO transparent electrodes 601 formed on the inner surface of the upper transparent substrate of the liquid crystal cell.
A stripe-shaped ITO transparent electrode 603 having an area slightly larger than 2 ″ is formed. In the example of FIG. 4, the Al reflective layer 602 overlaps the center of the ITO transparent electrode 603, whereas FIG. In the example, the Al reflective layer 602 ″ is overlapped on one side of the ITO transparent electrode 603. In a reflective display, external light incident on the liquid crystal cell is reflected by the reflective layer 5.
3 (in the case of FIG. 3), the reflective layer 602 (in the case of FIG. 4), the reflective layer 602 ′ (in the case of FIG. 5) or the reflective layer 602 ″ (FIG. 6).
In the case of). That is, external light is reflected by the reflection layer 50.
Only the light incident on 3, 602, 602 'or 602 "is modulated by the voltage applied to the liquid crystal layer. In transmissive display, of the light incident on the liquid crystal cell from the backlight, the reflective layers 503, 602 are provided. , 602 'or 602 ", only the source light is introduced into the liquid crystal layer. However, light incident on a portion other than the pixel electrode or the dot electrode has nothing to do with the display and only lowers the contrast of the transmissive display. Therefore, the display mode of the light-shielding film (black matrix layer) and the liquid crystal layer is set to normally black. To shut off. That is, the Al reflective layers 503, 602, 60
Light from the backlight incident on the portion of the ITO transparent electrode 504 or 603 which does not overlap with 2 ′ or 602 ″ enables transmission type display.

For example, in FIG. 4, I on the inner surface of the upper transparent substrate
The line width (L) of the TO transparent electrode 601 is 198 μm, and the line width (W) of the Al reflective layer 602 on the inner surface of the lower substrate is
If 1) is 46 μm and the line width (W2) of the ITO transparent electrode 603 formed thereon is 56 μm, about 70% of the external light introduced into the liquid crystal layer is reflected and emitted from the backlight. About 1% of the light introduced into the transparent substrate on the side
0% can be transmitted.

According to the configuration of the present embodiment as described above, a color liquid crystal device which can switch and display between a reflective display and a transmissive display without a double reflection or display bleeding is realized. In particular, according to the present embodiment, in order to transmit the light source light from the backlight at the time of the transmissive display, a large number of fine defects such as hole defects and pit defects and fine openings are provided in the reflective layer 216. Since there is no need to provide such a device, the structure of the device does not become complicated, no special process is additionally required in its manufacture, and the reliability of the liquid crystal device is improved.

In addition, since the ITO transparent electrode 215 is formed on the surface of the Al reflective layer 216 of this embodiment, the Al reflective layer 216 can be hardly damaged, and the Al reflective layer 216 and the ITO transparent electrode 215 can be hardly damaged. Are the electrode lines, so that the resistance of the electrode lines can be reduced. still,
Such a reflective layer 216 preferably contains 95% by weight or more of Al and has a layer thickness of 10 nm to 40 nm.
It is as follows.

Further, the scattering plate 207 disposed on the upper surface of the liquid crystal cell can emit the light reflected by the Al reflection layer 216 at a wide angle, so that a liquid crystal device having a wide viewing angle is realized.

(Second Embodiment) A liquid crystal device according to a second embodiment of the present invention will be described with reference to FIG. FIG. 7 is a schematic longitudinal sectional view showing the structure of the second embodiment of the liquid crystal device according to the present invention. Although this embodiment is basically related to a simple matrix type liquid crystal display device, it can be applied to an active matrix type device, another segment type device, and other liquid crystal devices with the same configuration. .

In this embodiment, as in the first embodiment, the liquid crystal layer 3 is placed between two transparent substrates 301 and 302.
A liquid crystal cell in which 03 is sealed with a frame-shaped sealing material 304 is formed. The liquid crystal layer 303 is composed of a nematic liquid crystal having a predetermined twist angle. A color filter 313 is formed on the inner surface of the upper transparent substrate 301, and three color layers of R, G, and B are arranged in the color filter 313 in a predetermined pattern. A transparent protective film 312 is coated on the surface of the color filter 313, and a plurality of stripe-shaped transparent electrodes 311 are formed on the surface of the protective film 312 by ITO or the like. An alignment film 310 is formed on the surface of the transparent electrode 311 and rubbed in a predetermined direction.

On the other hand, on the inner surface of the lower transparent substrate 302, a stripe-shaped reflection layer 317 having a larger area than the reflection layer 317 is formed on a stripe-shaped reflection layer 317 formed for each color layer of the color filter 313. A transparent electrode 315 is formed via a protective film 316. And the transparent electrode 3
11 are arranged so as to intersect. In the case of an active matrix type device including a TFD element and a TFT element, each of the reflective layers 317 and the transparent electrodes 315 are formed in a rectangular shape, and are connected to wiring via the active elements. The reflection layer 317 is formed of Cr, Al, or the like, and its surface is a reflection surface that reflects light incident from the transparent substrate 301 side. An alignment film 314 is formed on the surface of the transparent electrode 315 and rubbed in a predetermined direction.

As described above, in the second embodiment, each gap between the reflective layers 317 arranged in a stripe pattern at a predetermined interval has a function of transmitting light from the backlight.

The polarizing plate 3 is placed on the outer surface of the upper transparent substrate 301.
05, and a retardation plate 306 and a scattering plate 307 are disposed between the polarizing plate 305 and the transparent substrate 301, respectively. In addition, a retardation plate 309 is disposed below the liquid crystal cell and behind the transparent substrate 302.
Behind the polarizing plate 308. A fluorescent tube 319 that emits white light is provided below the polarizing plate 308.
Light guide plate 31 having an incident end face along fluorescent tube 319
8 is disposed. Light guide plate 3
Reference numeral 18 denotes a transparent body such as an acrylic resin plate on which a rough surface for scattering is formed on the entire back surface, or a printed layer for scattering is formed.
A substantially uniform light is emitted from the upper surface of the drawing. As another backlight, an LED (light emitting diode), an EL (electroluminescence), or the like can be used.

Next, with reference to FIG. 7, a description will be given of the reflective display and the transmissive display in the present embodiment configured as described above.

First, in the case of the reflection type display, external light entering the liquid crystal device from the upper side of the drawing is reflected by the polarizing plate 305 and the retardation plate 3.
06, the light passes through the scattering plate 307, passes through the color filter 313 and the liquid crystal layer 303, is reflected by the reflection layer 317, and is again emitted from the polarizing plate 305. At this time, a bright state, a dark state, and intermediate brightness can be controlled by a voltage applied to the liquid crystal layer 303.

In the case of a transmissive display, light from a backlight is converted into predetermined polarized light by a polarizing plate 308 and a retardation plate 309, and is introduced into a liquid crystal layer 303 and a color filter 313 from a gap where the reflective layer 317 is not formed. And
After that, the light passes through the scattering plate 307 and the phase difference plate 306. At this time, depending on the voltage applied to the liquid crystal layer 303, the polarizing plate 3
It is possible to control a state of transmitting (bright state), a state of absorbing (dark state), and an intermediate state (brightness).

The planar shapes of the transparent electrode 315 and the reflective layer 317 are the same as in the first embodiment.
FIG. 3 shows a case where the present invention is applied to an active matrix type liquid crystal device using FD elements, and FIGS. 4 to 6 shows a case where the present invention is applied to a simple matrix type liquid crystal device. .

For example, the I on the inner surface of the upper transparent substrate in FIG.
The line width (L) of the TO transparent electrode 601 is 240 μm, and the line width (W) of the Al reflection layer 602 on the inner surface of the lower substrate is
If 1) is set to 60 μm, and the line width (W2) of the ITO transparent electrode 603 formed thereon via the protective film is set to 70 μm, about 75% of the external light introduced into the liquid crystal layer is reflected, About 8% of the light emitted from the light and introduced into the lower transparent substrate can be transmitted.

According to the configuration of the present embodiment as described above, a color liquid crystal device capable of switching between a reflective display and a transmissive display without double reflection and blurring of display is realized. In particular, since it is not necessary to provide a large number of fine defects such as hole defects and pit defects and fine openings in the reflective layer 317, the device configuration does not become complicated, and a special process for manufacturing the device is not required. Is not additionally required.

Further, since the Al reflective layer 317 of the present embodiment has the protective film 316 formed on its surface and then the ITO transparent electrode 315, the Al reflective layer 317 is formed of ITO.
There is no direct contact with the developing solution or etching solution of the transparent electrode 315. Further, the presence of the protective film 316 made it difficult to damage. By short-circuiting the Al reflection layer 317 and the ITO transparent electrode 315, the probability of disconnection can be reduced and the resistance of the electrode line can be reduced.

Further, the scattering plate 307 disposed on the upper surface of the liquid crystal cell can emit the light reflected by the Al reflection layer 317 at a wide angle, so that a liquid crystal device having a wide viewing angle is realized.

(Third Embodiment) A third embodiment of the liquid crystal device according to the present invention will be described with reference to FIG. FIG. 8 is a schematic vertical sectional view showing the structure of the third embodiment of the liquid crystal device according to the present invention. The third embodiment has substantially the same configuration as the above-described second embodiment, and differs only in the structure of the reflective layer. still,
8, the same components as those in FIG. 7 according to the second embodiment are denoted by the same reference numerals, and description thereof will be omitted.

That is, in FIG. 8, the reflection layer 317 'is formed as follows.

First, a photosensitive resist is applied onto the inner surface of the transparent substrate 302 by spin coating or the like, and is exposed with a controlled amount of light through a mask having minute openings.
Thereafter, if necessary, the photosensitive resist is baked and developed. The portion corresponding to the opening of the mask is partially removed by development, and a support layer having a corrugated cross-sectional shape is formed. Here, only the portion corresponding to the opening of the mask is removed by the above photolithography process, or only the portion corresponding to the opening of the mask is left. May be formed, or another layer may be laminated on the surface of the support layer once formed to form a smoother surface.

Next, a metal film having a reflecting surface is formed by depositing a metal on the surface of the support layer by vapor deposition or sputtering to form a metal film having a reflection surface.
(See FIG. 3 or FIG. 5). Al, CrAg, Au or the like is used as the metal. Since the reflection layer 317 'is formed reflecting the shape according to the corrugations on the surface of the support layer, the surface is entirely roughened.

According to the configuration of the present embodiment as described above, it is possible to realize a color liquid crystal device capable of switching and displaying between a reflective display and a transmissive display without double reflection or blurring of display.

In particular, according to the present embodiment, the reflection layer 317 'provided with the unevenness can reflect the reflected light at a wide angle, so that a liquid crystal device having a wide viewing angle is realized.

(Fourth Embodiment) A fourth embodiment of the liquid crystal device according to the present invention will be described with reference to FIGS. FIG. 9 is a schematic vertical sectional view showing the structure of the fourth embodiment of the liquid crystal device according to the present invention. Although this embodiment is basically related to a simple matrix type liquid crystal display device, it can be applied to an active matrix type device, another segment type device, and other liquid crystal devices with the same configuration. .

In this embodiment, two transparent substrates 401
The liquid crystal layer 403 has a frame-like sealing material 404 between
To form a sealed liquid crystal cell. The liquid crystal layer 403 is composed of a nematic liquid crystal having a negative dielectric anisotropy. On the inner surface of the upper transparent substrate 401, a plurality of stripe-shaped transparent electrodes 409 are formed by ITO or the like. On the surface of the transparent electrode 409, an alignment film 410 for vertically aligning liquid crystal is formed. Rubbing treatment is performed in the direction. Due to this rubbing treatment, the liquid crystal molecules have a pretilt angle of about 85 degrees in the rubbing direction. In the case of an active matrix type device including a TFD element and a TFT element, the transparent electrode 409 is formed in a rectangular shape and is connected to a wiring via the active element.

On the other hand, on the inner surface of the lower transparent substrate 402, a height of about 0.8 μm
Al having 1.0% by weight of Nd added thereto was sputtered to a thickness of 25 nm on the surface thereof, and then striped (see FIG. 4 or FIG. 6) or island-shaped (see FIG. 3 or FIG. 5) to form a reflective layer 411. On the reflective layer 411, a color filter 414 is formed via a protective film 412. On the color filter 414, three colored layers of R, G, and B are arranged in a predetermined pattern. A transparent protective film 415 is coated on the surface of the color filter 414, and a plurality of stripe-shaped transparent electrodes 41 are formed on the surface of the protective film 415.
6 is formed of an ITO film or the like so as to intersect the transparent electrode 409 for each color layer of the color filter 414. An alignment film 417 is formed on the surface of the transparent electrode 416. Note that rubbing treatment is not performed on the alignment film 417.

The polarizing plate 4 is formed on the outer surface of the upper transparent substrate 401.
A retardation plate (1/4 wavelength plate) 406 is disposed between the polarizing plate 405 and the transparent substrate 401.
A retardation plate (1/4 wavelength plate) 408 is disposed behind the transparent substrate 402 below the liquid crystal cell, and a polarizing plate 407 is disposed behind the retardation plate (1/4 wavelength plate) 408. Are located. A backlight having a fluorescent tube 419 for emitting white light and a light guide plate 418 having an incident end face along the fluorescent tube 419 is disposed behind the polarizing plate 407. The light guide plate 418 is a transparent body such as an acrylic resin plate on which a rough surface for scattering is formed on the entire back surface or a printed layer for scattering is formed.
9 is received at the end face, and substantially uniform light is emitted from the upper surface of the drawing. As another backlight, an LED (light emitting diode), an EL (electroluminescence), or the like can be used.

In this embodiment, in order to prevent light from leaking from the area between the dots during the transmissive display, the black matrix layer 413 which is a light shielding portion formed between the colored layers of the color filter 414 is formed. It is provided substantially corresponding to a plane. The black matrix layer 413 is formed by depositing a Cr layer or using a photosensitive black resin.

As shown in FIG. 10A, the transmission axes P1 and P2 of the polarizing plate 405 and the polarizing plate 407 are set in the same direction, and the transmission axes P1 and P2 of these polarizing plates are The directions of the slow axes C1 and C2 of the phase difference plates (1/4 wavelength plates) 406 and 408 are set to directions rotated by θ = 45 degrees clockwise. Further, the transparent substrate 401
The direction R1 of the rubbing treatment of the alignment film 410 on the inner surface is also performed in a direction coinciding with the directions of the slow axes C1 and C2 of the phase difference plates (1/4 wavelength plates) 406 and 408.
The rubbing direction R1 defines the direction in which the long axis of the liquid crystal molecules falls when an electric field is applied to the liquid crystal layer 403. Liquid crystal layer 4
For 03, a negative nematic liquid crystal is used.

FIG. 10B shows a driving voltage characteristic of the reflectance R in the reflection type display according to the present embodiment and a driving voltage characteristic of the transmittance T in the transmission type display. The display state when no electric field is applied is dark (black). When this liquid crystal cell is used, it is not necessary to form the black matrix layer 413.

Next, with reference to FIG. 9, a description will be given of the reflective display and the transmissive display in the present embodiment configured as described above.

First, in the case of the reflection type display, external light incident on the liquid crystal device from the upper side of the drawing is reflected by the polarizing plate 405 and the retardation plate 4.
06 pass through the liquid crystal layer 403, pass through the color filter 414, are reflected by the reflective layer 411, and are again emitted from the polarizing plate 405. At this time, the bright state, the dark state, and the intermediate brightness are controlled by the voltage applied to the liquid crystal layer 403.

In the case of a transmissive display, light from a backlight is converted into predetermined polarized light by a polarizing plate 407 and a phase difference plate 408, introduced into the liquid crystal layer 403 from each gap of the reflective layer 411, After passing through 403, the light passes through the phase difference plate 406. At this time, the liquid crystal layer 40
Depending on the voltage applied to 3, the state of transmission (bright state) from the polarizing plate 405, the state of absorption (dark state), and the intermediate brightness can be controlled.

According to the configuration of the present embodiment as described above, a color liquid crystal device capable of switching and displaying between a reflective display and a transmissive display without double reflection or display bleeding is realized.

The reflective layer 411 of this embodiment has Al
Is covered with a protective film 412 using a metal layer mainly composed of, for example, a color filter 414, a protective film 415,
A transparent electrode 416 is formed. For this reason, since the Al metal layer does not directly come into contact with the ITO developer or the color filter developer, the Al metal layer does not dissolve in the developer. Further, the Al metal layer which is easily damaged can be easily handled. For example, Al having a thickness of 25 nm to which 1.0 wt% of Nd is added has a reflectance of 80% and a transmittance of 1%.
It shows a value of 0% and functions sufficiently as the reflective layer 411.

Further, the reflection layer 411 provided with irregularities can reflect the reflected light at a wide angle, so that a liquid crystal device having a wide viewing angle is realized.

(Fifth Embodiment) A fifth embodiment of the liquid crystal device according to the present invention will be described with reference to FIG. FIG. 11 is a schematic longitudinal sectional view of a fifth embodiment of the liquid crystal device according to the present invention. The fifth embodiment has substantially the same configuration as that of the above-described second embodiment, and differs in the structure relating to the reflective layer and its protective film. In FIG. 11, the same components as those in FIG. 7 according to the second embodiment are denoted by the same reference numerals, and description thereof will be omitted.

That is, in FIG. 11, a reflective layer 617 is formed as a reflective layer made of aluminum by 50 to 3 by an evaporation method.
Each dot is formed in an island shape or a stripe shape with a thickness of 00 nm (see FIGS. 3 to 6). It is preferable that aluminum is used for the reflective layer 617, but other metals such as chromium can be used instead.

Further, a protective film is not formed on the reflective layer 617 as in the second embodiment, and is made of Al ₂ O ₃ or (aluminum oxide) by anodizing the reflective layer after vapor deposition. An insulating layer 616 is formed. The anodic oxidation is carried out using a solution containing 1 to 10% by weight of ammonium salicylate and 20 to 80% by weight of ethylene glycol at a formation voltage of 5 to 250 V and a current density of 0.001 to 0.1 mA /.
It may be performed under the condition of cm ² . When the thickness of the oxide film thus formed is 140 nm or an integral multiple thereof, coloring due to interference can be prevented. Then, a transparent electrode 615 is disposed on the insulating layer 616, and the other configuration is the same as that of the second embodiment shown in FIG.

As described above, according to the fifth embodiment, an extremely thin insulating film 616 having high insulating properties can be obtained. In particular, by forming the reflective layer 617 from aluminum, its reflectance can be maintained even after oxidation. When the insulating film 616 is formed by oxidation, anodic oxidation may be used, or thermal oxidation may be used.

(Sixth Embodiment) A sixth embodiment of the liquid crystal device according to the present invention will be described with reference to FIG. FIG.
It is sectional drawing which expands and shows the TFT drive element in 6th Embodiment of this invention with a pixel electrode etc. In the sixth embodiment, a TFT drive element is formed on a substrate and connected to a transparent electrode formed on the TFT drive element via an insulating film.
It is applicable to each embodiment of the present invention.

In FIG. 12, a gate electrode 722, a gate insulating film 723, an i-Si layer 724, and an n ⁺ -Si layer 72 are formed on an interlayer insulating film 721 formed on a transparent substrate 702.
5. T having source electrode 726 and drain electrode 727
An FT element is provided. The reflective layer 728 made of aluminum is formed on the interlayer insulating film 731 formed on the TFT element, and the reflective layer 728 is provided with an insulating layer 729 formed by anodizing the deposited reflective layer. On the insulating layer 729, a transparent electrode 730 made of ITO connected to the drain electrode 727 via a contact hole is provided.
(Pixel electrode) is formed.

As described above, according to the sixth embodiment, each transparent electrode (pixel electrode) 730 is provided via a TFT element.
, The crosstalk between the transparent electrodes 730 can be reduced, and higher-quality image display can be performed. The TFT element configured as described above may be a TFT having any structure such as an LDD structure, an offset structure, and a self-aligned structure. Further, in addition to the single gate structure, a dual gate or triple gate or more may be used.

(Seventh Embodiment) A seventh embodiment of the liquid crystal device according to the present invention will be described with reference to FIG. FIG.
It is sectional drawing which expands and shows the TFD drive element in 7th Embodiment of this invention with a pixel electrode etc. The configuration in which a TFD drive element is formed on a substrate in the seventh embodiment and connected to a transparent electrode formed on the TFD drive element via an insulating film is as follows.
It is applicable to each embodiment of the present invention.

In FIG. 13, a first conductive layer 841 made of tantalum is formed on an interlayer insulating film 821 formed on a substrate 802, and tantalum is anodically oxidized on the first conductive layer 841. The obtained insulating layer 842 is formed. A second conductive layer 8 made of chromium is formed on the insulating layer 842.
43 are formed. A reflective layer 844 made of aluminum is formed on the interlayer insulating film 821, and an insulating film 845 obtained by anodizing the deposited reflective layer is formed on the reflective layer 844. The transparent electrode (pixel electrode) 846 formed over the insulating film 845 is
It is connected to the.

As described above, according to the seventh embodiment, each transparent electrode (pixel electrode) 846 is provided via the TFD element.
, The crosstalk between the transparent electrodes 846 can be reduced, and higher-quality image display can be performed. It should be noted that a two-terminal nonlinear element having bidirectional diode characteristics such as a ZnO (zinc oxide) varistor, an MSI (Metal Semi-Insulator) driving element, and an RD (Ring Diode) is provided in place of the illustrated TFD element. Is also good.

(Eighth Embodiment) An eighth embodiment of the liquid crystal device according to the present invention will be described with reference to FIG. FIG. 14 is a schematic longitudinal sectional view of an eighth embodiment of the liquid crystal device according to the present invention. The eighth embodiment has substantially the same configuration as the above-described fifth embodiment, but differs in the structure related to the insulating film. FIG.
In the figure, the same reference numerals are given to the same components as those in FIG. 11 according to the fifth embodiment, and the description thereof will be omitted.

That is, in FIG. 14, the insulating layer provided on the reflective layer 617 disposed at a predetermined interval has a multilayer structure including insulating films 616a and 616b. More specifically, in addition to an oxide film 616a obtained by anodizing the reflective layer 617 made of metal, an insulating film 616b coated with an organic substance by spin coating is formed as an insulating layer. In addition, as the insulating film 616b, an SiO ₂ film or the like may be deposited in addition to the organic insulating film. The other points are the same as in the fifth embodiment, and a description thereof will not be repeated.

As described above, according to the eighth embodiment, the insulating property of the insulating film can be improved. In addition, an oxide of aluminum or the like can be used for one insulating film, and an SiO ₂ film or an overcoat film made of an organic substance can be used as the other insulating film. When such an SiO ₂ film is formed, The organic film may be formed by vapor deposition, sputtering, or CVD, and may be formed by spin coating or the like when forming the organic film.

In each of the embodiments described above, the reflection layer 2
16, 317, 317 ′, 411, etc., the light from the backlight is transmitted. In addition to this, a fine opening or slit is formed in the reflection layer itself, so that the backlight is formed. The light from the light may be introduced into the liquid crystal layer not only through the gap but also through the opening. In this case, one or a plurality of openings such as a square, a rectangle, a slit, a circle, and an ellipse may be arranged regularly or irregularly for each pixel. In this case, preferably,
The total area of the openings is provided at a rate of about 10% with respect to the total area of the reflective layer. Such an opening can be easily formed in a photo process / developing process / stripping process using a resist. It is also possible to open the opening at the same time as forming the reflective layer, so that the number of manufacturing steps does not need to be increased. Also, in any shape, the diameter of the opening is preferably 0.01 μm or more and 20 μm or less, and the opening is 5% or more and 30% or less of the reflection layer.
It is preferable to form with the following area ratio.

The coloring layers such as the color filters 213, 313, and 414 used in the first to tenth embodiments described above will be described with reference to FIG. FIG. 15 is a characteristic diagram showing the transmittance of each colored layer such as the color filter 213. In each embodiment, when performing the reflective display, the incident light passes through one of the coloring layers such as the color filter 213 and then passes through the liquid crystal layer, is reflected by the reflecting layer, and passes through the coloring layer again. And then released. Therefore, unlike a normal transmission type liquid crystal device, the light passes through the color filter 213 and the like twice, so that the display becomes dark and the contrast is reduced in the normal color filter. Therefore, in each embodiment, as shown in FIG. 19, the R, G, and B colored layers of the color filter 213 and the like are formed in a light color so that the minimum transmittance 61 in the visible region becomes 25 to 50%. ing. Lightening of the colored layer is achieved by reducing the thickness of the colored layer or reducing the concentration of the pigment or dye mixed in the colored layer. Thus, it is possible to configure so as not to lower the brightness of the display when performing the reflective display.

The lightening of the color filter 213 and the like is performed by
In the case of performing transmissive display, the light is transmitted only once through the color filter 213 and the like, so that the display is lightened. However, in each embodiment, a large amount of light from the backlight is often blocked by the reflective layer. This is rather convenient in securing brightness.

(Ninth Embodiment) A ninth embodiment of the present invention will be described with reference to FIG. The ninth embodiment is an embodiment of an electronic apparatus including any one of the first to eighth embodiments described above. That is, the ninth embodiment is directed to various electronic devices that suitably use the liquid crystal device described in the above first to eighth embodiments as a display unit of a portable device that requires low power consumption in various environments. Get involved. FIG. 16 shows three examples of the electronic device of the present invention.

FIG. 16A shows a mobile phone, and the main body 7
A display unit 72 is provided in an upper part of the front surface of the device 1. Mobile phones are used in all environments, both indoors and outdoors. Especially, it is often used in cars, but the inside of cars at night is very dark. Therefore, it is desirable that the display device used in the mobile phone is a transflective liquid crystal device capable of performing transmissive display using auxiliary light as needed, mainly reflective display with low power consumption. When the liquid crystal device described in the first to eighth embodiments is used as the display unit 72 of the mobile phone, a mobile phone that is brighter and has a higher contrast ratio than the conventional one in both the reflective display and the transmissive display can be obtained.

FIG. 16B shows a watch, in which a display section 74 is provided at the center 73 of the main body. An important aspect in watch applications is luxury. The liquid crystal described in the first embodiment to the eighth embodiment of the present invention is displayed on the display unit 7 of the watch.
When used as 4, the coloration is small because the characteristic change due to the light wavelength is small, as well as bright and high contrast. Therefore, a very high-quality color display can be obtained as compared with the conventional watch.

FIG. 16C shows a portable information device, in which a display section 76 is provided above a main body 75 and an input section 77 is provided below. In addition, touch keys are often provided on the front surface of the display unit 76. Normal touch keys have a lot of surface reflections, making it difficult to see the display. Therefore, conventionally, a transmissive liquid crystal device is often used as a display even though it is a portable type. However, since the transmissive liquid crystal device always uses a backlight, the power consumption is large and the battery life is short. Even in such a case, if the liquid crystal device according to the first to eighth embodiments described above is used as the display unit 76 of the portable information device, the display is bright and vivid regardless of the reflective type, the transflective type, or the transmissive type. Information equipment can be obtained.

The liquid crystal device of the present invention is not limited to the above-described embodiments, but can be appropriately changed without departing from the spirit or spirit of the invention which can be read from the claims and the entire specification. A liquid crystal device with a change is also included in the technical scope of the present invention.

[Brief description of the drawings]

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

FIG. 2 is a conceptual diagram schematically showing the state of an electric field applied to a liquid crystal layer by a transflective electrode having a single-layer structure in a comparative example (FIG. 2A), and the transflective reflection in the first embodiment. FIG. 2 is a conceptual diagram schematically showing a state of an electric field applied to a liquid crystal layer by a transparent electrode laminated on the layer (FIG. 2).
(B)).

FIG. 3 is a plan view illustrating an example of a reflective layer disposed with a gap in the first embodiment.

FIG. 4 is a plan view showing another example of the reflection layer arranged with a gap in the first embodiment.

FIG. 5 is a plan view showing another example of the reflective layer arranged with a gap in the first embodiment.

FIG. 6 is a plan view showing another example of the reflection layer arranged with a gap in the first embodiment.

FIG. 7 is a schematic longitudinal sectional view showing a schematic structure of a liquid crystal device according to a second embodiment of the invention.

FIG. 8 is a schematic longitudinal sectional view showing a schematic structure of a liquid crystal device according to a third embodiment of the present invention.

FIG. 9 is a schematic vertical sectional view showing a schematic structure of a fourth embodiment of the liquid crystal device according to the present invention.

FIG. 10 is an explanatory diagram showing a relationship between a rubbing direction of a polarizing plate, a retardation plate, and a liquid crystal cell of a fourth embodiment (FIG. 10A).
FIG. 10B is a characteristic diagram showing a driving voltage-reflectance R / transmittance T characteristic of the liquid crystal device at this time (FIG. 10B).

FIG. 11 is a schematic vertical sectional view showing a schematic structure of a liquid crystal device according to a fifth embodiment of the present invention.

FIG. 12 is an enlarged sectional view showing a TFT driving element according to a sixth embodiment of the present invention together with a pixel electrode and the like.

FIG. 13 is an enlarged sectional view showing a TFD drive element according to a seventh embodiment of the present invention together with a pixel electrode and the like.

FIG. 14 is a schematic vertical sectional view showing a schematic structure of an eighth embodiment of the liquid crystal device according to the present invention.

FIG. 15 is a graph showing light transmittance of each color layer of a color filter in each embodiment.

FIG. 16 is a schematic perspective view of various electronic devices according to a ninth embodiment of the present invention.

[Explanation of symbols]

201, 202, 301, 302, 401, 402: transparent substrate 203, 303, 403: liquid crystal layer 204, 304, 404: sealing material 205, 208, 305, 308, 405, 407: polarizing plate 206, 209, 306; 309, 406, 408: retardation plates 207, 307: scattering plates 211, 215, 311, 315, 409, 416, 6
15: Transparent electrode 210, 214, 310, 314, 410, 417: Alignment film 212, 312, 316, 412, 415: Protective film 213, 313, 414: Color filter 216, 317, 317 ', 411, 617: Reflection Layers 217, 318, 418 Light guide plate 218, 319, 419 Fluorescent tube 413 Black matrix layer (light shielding film) 501 Scanning line 502 TFD element 601 Transparent electrode formed on inner surface of upper substrate 603 Lower substrate Transparent electrode formed on inner surface

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Eiji Okamoto, Inventor 3-3-5 Yamato, Suwa City, Nagano Prefecture Inside Seiko Epson Corporation (72) Inventor Seki ▲ Takumi, 3-5, Yamato, Suwa City, Nagano Prefecture No. Seiko Epson Corporation

Claims (12)

[Claims] 1. A pair of transparent first and second substrates, a liquid crystal layer sandwiched between the first and second substrates, and a liquid crystal layer formed on a surface of the second substrate on the liquid crystal layer side. ,
A plurality of reflective layers each separated from each other when viewed in a plan view from a direction perpendicular to the second substrate; and a plurality of reflective layers formed so as to partially overlap the reflective layers and viewed in a plan view. A liquid crystal device comprising: a transparent electrode including a non-overlapping portion; and a lighting device disposed on a side of the second substrate opposite to the liquid crystal layer. 2. The liquid crystal device according to claim 1, wherein the transparent electrode is formed so that an area thereof is larger than an area of the reflection layer. 3. The liquid crystal device according to claim 1, wherein the transparent electrode and the reflection layer are formed in a stripe shape. 4. The liquid crystal device according to claim 1, wherein the transparent electrode and the reflection layer are formed in an island shape. 5. The liquid crystal device according to claim 1, wherein the transparent electrode is formed directly on the reflection layer. 6. The transparent electrode according to claim 1, wherein the transparent electrode is formed on the reflective layer via at least one of an insulating film, a color filter, and a protective film. 3. The liquid crystal device according to claim 1. 7. The method according to claim 1, wherein the transparent electrode is formed on the reflective layer via an insulating film, and the insulating film is formed by oxidizing a surface portion of the reflective layer. 5. The liquid crystal device according to any one of 4. 8. The semiconductor device according to claim 7, wherein the insulating film is formed by laminating two or more different types of insulating films.
3. The liquid crystal device according to claim 1. 9. The liquid crystal device according to claim 1, wherein a non-driving state is a dark (black) state. 10. The reflective layer comprises 95% by weight or more of Al
10. The liquid crystal device according to claim 1, wherein the thickness is 10 nm or more and 40 nm or less. 11. The liquid crystal device according to claim 1, wherein the reflection layer has irregularities. 12. An electronic apparatus comprising the liquid crystal device according to claim 1. Description: