JPH08190101A - Liquid crystal display element - Google Patents

Abstract

PURPOSE: To display the colors or gradations at the peripheral edge of a display region according to setting. CONSTITUTION: A picture frame-like peripheral electrode 26 is formed at the peripheral part of the display region of a glass substrate 21 and a peripheral electrode part 28A constituting a part of a common electrode 28 is formed at the position of another region of a glass substrate 22 facing the peripheral electrode 26. The display of the colors or gradations meeting the setting at the peripheral part of the display region is made possible by controlling the impressed voltage between the peripheral electrode 26 and the peripheral electrode part 28A. The easily visible liquid crystal display element is, therefore, realized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly to a liquid crystal display device for displaying color.

[0002]

2. Description of the Related Art Conventionally, a liquid crystal display device having a structure as shown in FIG. 12 is generally known. This liquid crystal display device has a pair of glass substrates 1, 2 as shown in FIG.
Are bonded so as to face each other with a sealant 3 interposed therebetween, and the liquid crystal 4 is sealed in the gap between the glass substrates 1 and 2. A thin film transistor (TFT) 5 as a switching element and a pixel electrode 6 connected to the thin film transistor (TFT) 5 are formed for each pixel on the opposite inner surface of one glass substrate 1, and an alignment film 7 is formed on the entire display region.
Is provided. In addition, a common electrode 8 is formed on the opposite inner side surface of the other glass substrate 2 over the entire display area, and an alignment film 9 is provided on the surface of the common electrode 8. Outside the glass substrates 1 and 2, the polarizers 10 and 11 are provided.
Are arranged with their polarization axes set in a predetermined direction. Then, by applying an electric field to each pixel, the initial molecular alignment of the liquid crystal is deformed, and the transmittance of the light polarized by the polarization action of the liquid crystal generated at that time is arranged on the outside of the glass substrates 1 and 2. It is adjusted and displayed using 10 and 11.

[0003]

In such a liquid crystal display element, the peripheral portion of the display area (the outer peripheral portion of the pixel area).
Since there is no electrode sandwiching the liquid crystal 4 (only the common electrode 8 exists), the electric field is not always applied to the liquid crystal, and it is left as it is determined by the optical state when there is no electric field. That is, this portion (the peripheral portion of the display area) was a white portion or a black portion. Further, as another example, there is one in which a so-called black mask is formed in the peripheral portion of the display area so that the display portion is always a black portion. In this way, if the peripheral portion of the display area is always a white portion or a black portion, it is easy for the eyes to be tired and easy to see when viewed for a long time depending on the light incident on the liquid crystal display element body and its surroundings and the display image. I could not say. It is an object of the present invention to provide an ergonomically easy-to-view liquid crystal display element that can display a color or gradation on the peripheral portion of the display area and can have a desired frame pattern.

[0004]

Therefore, according to the present invention,
In a liquid crystal display device comprising a liquid crystal cell in which liquid crystal is sealed between a pair of substrates each having a display electrode provided in a display area on the opposite surface, a peripheral electrode formed continuously between or around the display area. It is characterized by having. In the invention according to claim 2, the display electrodes on one of the pair of substrates are arranged in a matrix, and switching elements are connected to the display electrodes, respectively. Further, in the invention according to claim 3, the switching element includes a gate insulating film, a semiconductor layer and a gate electrode arranged to face each other with the gate insulating film interposed therebetween, and a source electrode connected to each of the semiconductor layers. And a drain electrode, wherein the gate electrode is connected to a gate line connected to a scan drive circuit, and the drain electrode is connected to a drain line connected to a signal drive circuit. And Further, in the invention according to claim 4, the peripheral electrode is insulated from the gate line and the drain line via the gate insulating film and faces one of the gate line and the drain line of the gate insulating film. It is characterized in that the source electrode, the drain electrode, and the gate electrode are continuously connected to each other by a connecting electrode formed on the surface opposite to the surface by any one of the same materials. In a fifth aspect of the present invention, the peripheral electrodes of the pair of substrates different from the substrate on which the switching element is provided are formed of the same material as the display electrodes. According to a sixth aspect of the invention, the terminal of the wiring connected to the peripheral electrode of the substrate provided with the thin film transistor extends to one side surface of the substrate where the terminal of the drain line is provided. In the invention according to claim 7, polarizing plates are respectively provided on both outer side surfaces of the pair of substrates, and the liquid crystal between the peripheral electrodes changes the retardation according to a voltage applied to the peripheral electrodes, It is characterized in that the elliptically polarizing action of the liquid crystal is changed to change the color of light transmitted through the polarizing plate. The invention according to claim 8 is characterized in that at least one retardation plate is provided between the polarizing plates on both outer surfaces of the pair of substrates. The invention according to claim 9 is characterized in that a reflector is provided below the pair of substrates.

[0005]

According to the first aspect of the present invention, even if there is light incident on the liquid crystal display element body or light around the element, which affects the contrast of the display area of the liquid crystal display element, the image of the display area is displayed. Accordingly, by applying a voltage between the peripheral electrodes provided in the peripheral portion of the display area, it is possible to select and display the color and gradation of the peripheral portion, so that the liquid crystal sealed between the two substrates is displayed. It is possible to make it easy to visually recognize for a long time without changing the display state of the display area.
Also, depending on the individual difference in the visibility of the liquid crystal display element of each person,
Various colors and gradations can be displayed by appropriately adjusting the voltage applied in the peripheral portion. According to the second aspect of the invention, even for displaying a moving image in the display area by the switching element,
Flickering of eyes can be suppressed. According to the third aspect of the invention, the thin film transistor enables display with better color and gradation. Further, in the invention according to claim 4, the peripheral electrode is insulated from the gate line and the drain line through the gate insulating film, and is provided on the opposite side of the surface of the gate insulating film facing one of the gate line and the drain line. Since they are continuously connected to each other by the connection electrode formed on the surface, when forming the peripheral electrode across the gate line and the drain line,
It is possible to continuously conduct electricity by the connection electrodes, and it is not necessary to input a signal voltage for each peripheral electrode divided for each line, so that it is possible to suppress an increase in the number of terminals of the drive circuit, and The connection electrode can be formed together with the thin film transistor by using the same material as the electrode of the thin film transistor, and since the peripheral electrode and each line are insulated by the gate insulating film, an etching mask for forming the electrode in the manufacturing process. However, there is no need to add a new process. According to the invention of claim 5,
Since the peripheral electrodes of the pair of substrates different from the substrate on which the switching element is provided can be collectively formed by using the same material as the display electrodes,
In the manufacturing process, it is only necessary to change the etching mask to the pattern of the peripheral electrode and the counter electrode, there is no need to add a step of forming a new electrode, the manufacturing can be easily performed, and the driving waveform is By making the counter electrode the same, it is not necessary to change the drive waveform of the drive circuit on the counter electrode side. In the invention according to claim 6, since the terminal of the wiring connected to the peripheral electrode of the substrate provided with the thin film transistor extends to one side surface of the substrate where the terminal of the drain line is provided, the drain line Since it can be easily connected to the signal drive circuit connected to, and the signal voltage can be input to the peripheral electrodes in synchronization with the signal voltage input for each row of thin film transistors arranged in a matrix, Even if the electrode has a small storage capacity, the display can be sufficiently held. In the invention according to claim 7, it is possible to perform color display by changing the retardation of the liquid crystal of the peripheral electrode without using a color filter. In the invention according to claim 8, the retardation plate polarizes the light elliptically polarized by the liquid crystal so as to achieve better color separation, and enables display of clearer colors. According to the invention described in claim 9, it is possible to perform display with a stronger color tone by the reflection of the reflection plate even with the same light amount as compared with the transmissive type.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the liquid crystal display element according to the present invention will be described below with reference to the embodiments shown in the drawings. FIG. 1 is a sectional view showing a main part of this embodiment. As shown in the figure, in the liquid crystal display element of the present embodiment, the lower glass substrate 21 and the upper glass substrate 22 as a pair of transparent substrates are bonded so as to face each other with a sealing material 23, and both glass substrates 21, A liquid crystal 30 is enclosed in a gap formed by the sealing material 23 and the sealing material 23. For each pixel on the facing inner surface of the lower glass substrate 21,
A thin film transistor (hereinafter referred to as a TFT) 24 provided as a switching element and a pixel electrode 25 as a display electrode made of ITO and connected to each TFT 24 are formed. Further, as shown in FIG. 2, a frame-shaped peripheral electrode 26 made of the same material as the pixel electrode 25 is formed in the peripheral portion of the display region P of the lower glass substrate 21 so as to surround the peripheral region of the display region. . In the figure, 26A is a takeout terminal of the peripheral electrode 26, DL is a drain line,
GL indicates a gate line. Since the peripheral electrode 26 can be formed simultaneously with the patterning of the pixel electrode 25 in the manufacturing process, the number of processes is not increased. Then, as shown in FIG. 1, an alignment layer 27 is formed on the TFT 24, the pixel electrode 25, and the peripheral electrode 26. In addition, on the inner surface of the upper glass substrate 22 facing each other, a common electrode 2 as a display electrode made of, for example, ITO.
8 is formed on the entire surface of the display area, and the common electrode 28 is formed on the alignment layer 2
9 is formed so as to cover. The peripheral portion of the common electrode 28 is a peripheral electrode portion 28A facing the peripheral electrode 26 on the lower glass substrate 21 side.

The liquid crystal 30 is made of, for example, nematic liquid crystal to which a chiral liquid crystal is added. If the product Δn · d of the optical anisotropy Δn of the liquid crystal 30 and the layer thickness d is too large, the viewing angle becomes narrow and the response speed becomes slow. Further, the display color changes abruptly due to a slight change in the applied voltage, which is not preferable. If Δn · d is too small, full-color display becomes difficult. Therefore, in this embodiment, the liquid crystal 3
Optical anisotropy Δn of 0 is 0.19 to 0.25, liquid crystal layer thickness d
Is 4 to 5 μm, and the product Δn · d is 0.7 μm or more and less than 1.1 μm, and preferably 0.85 μm to 1.05.
μm, more preferably 0.95 μm to 1.03 μm
Set to.

Below the lower glass substrate 21, a lower polarizing plate 31 is provided.
, The retardation plate 35 is disposed on the upper glass substrate 22, and the upper polarizing plate 33 is disposed on the retardation plate 35. The retardation plate 35 is, for example, manufactured by stretching a polycarbonate-based resin, is composed of a biaxial retardation plate having a retardation in the thickness direction, and has a retardation ((nx-ny) · d) of, for example, 370nm ± 30n
m, Nz coefficient value (nx-nz) / (nx-ny) is 0.
2 to 0.8. Here, nx is the refractive index in the direction in which the refractive index is maximum on the plane of the retardation plate, ny is the refractive index in the direction orthogonal to the direction of nx on the plane of the retardation plate, and nz is the direction of nx and The refractive index in the direction orthogonal to the ny direction is shown.

The optical axes of the upper and lower polarizing plates 33 and 31 and the phase difference plate 35 are set with reference to the alignment processing direction of the alignment film 27. A reflection plate 32 is arranged below the lower polarization plate 31.
As shown in FIG. 7, the alignment treatment direction 29 of the upper alignment film 29 is shown.
a, it intersects with the alignment treatment direction 27a of the lower alignment film 27 at 90 degrees counterclockwise. As a result, the liquid crystal molecules move from the lower glass substrate 21 side toward the upper glass substrate 22 by 90 degrees.
It becomes a twisted orientation state.

Further, the transmission axis 33a of the upper polarizing plate 33 intersects with the orientation processing direction 27a of the lower alignment film 27 at 170 degrees, and the transmission axis 31a of the lower polarizing plate 31 is of the lower alignment film 27. It intersects the alignment treatment direction 27a at 150 degrees. That is, the transmission axis 31a of the lower polarizing plate 31 and the transmission axis 33a of the upper polarizing plate 33 intersect at approximately 20 degrees. The retardation plate 35 has its stretching axis (the axis having the largest refractive index on the plane) 35 a intersecting the alignment treatment direction 27 a of the lower alignment film 27 at 150 °, that is, the transmission axis of the lower polarizing plate 31. It is arranged so as to be parallel to 31a.

According to the liquid crystal display device having such a structure,
By controlling the voltage applied between the pixel electrode 25 and the common electrode 28, the alignment state of the liquid crystal molecules is changed. Along with the change in the alignment state of the liquid crystal molecules, the synthetic retardation of the liquid crystal layer and the retardation film 35 also changes, and different birefringence occurs for each wavelength. Therefore, the peak wavelength of the light emitted from the upper polarizing plate 33 changes according to the change of the applied voltage, and the display color changes. That is, the display color (hue) can be controlled by controlling the voltage applied between the pixel electrode 25 and the common electrode 28. The change in the retardation of the liquid crystal depends on the magnitude of Δn · d. Therefore, if Δn · d is too large, the display color changes abruptly in response to changes in applied voltage, and Δn · d
If d is too small, the display color hardly changes even if the applied voltage is changed.

In this embodiment, by adopting the optical arrangement of the liquid crystal 30 having Δn · d of 0.7 μm or more and less than 1.1 μm, the biaxial retardation plate 35, and the polarizing plates 31 and 33, red,
Green, blue, black, and white can be displayed, and so-called full-color display can be performed. In addition, the contrast is high and the color purity is excellent. Moreover, since the twist angle of the liquid crystal molecules is as small as 90 degrees, the response speed is fast and a moving image or the like can be displayed. Twisting the liquid crystal by about 90 degrees is possible with almost all liquid crystal materials, and the selection range of the liquid crystal material and the material of the alignment film is widened. In the present embodiment, by controlling the applied voltage to the crown of the peripheral electrode 26 and the peripheral electrode portion 28A, the display area according to the display state of the display area (excluding the peripheral portion) in which the plurality of pixel electrodes 25 are assembled. It is possible to change the color and gradation of the peripheral portion of the. Further, it is possible to change the color and gradation of the peripheral portion of the display area according to the brightness of the surroundings. At the peripheral portion of the display area in this state, the upper polarizing plate 33, the retardation film 35, the upper glass substrate 22,
Incident light that has sequentially passed through the liquid crystal 30, the lower glass substrate 21, and the lower polarizing plate 31 is reflected by the reflecting plate 32, the reflected light is directly polarized by the lower polarizing plate 31, and then passes through the liquid crystal 30 to be elliptically polarized. The light transmitted through the upper polarizing plate 33 is set to be colored light.

Next, the peripheral electrode 26 will be described with reference to FIGS.
The detailed structure of will be described. As shown in FIG. 3, in the inner region surrounded by the peripheral electrodes 26 at the peripheral portion of the display region P,
A TFT 24 and a pixel electrode 25 are formed for each pixel.
The gate electrode G of the TFT 24 is connected to the gate line GL, the source electrode S is connected to the pixel electrode 25, and the drain electrode D is connected to the drain line DL. FIG.
3 shows the structure of the aa cross section of FIG. 3 (a portion of the peripheral electrode 26 that crosses the drain line DL). As shown in the figure, the drain line DL and the frame-shaped peripheral electrode 2
On the lower glass substrate 21 in the region where 6 intersects, an interconnect electrode 36 formed together with the gate electrode G is provided. An insulating film 34 is formed on the interconnect electrode 36 and the lower glass substrate 21 together with the gate insulating film of the TFT 24. Further, the peripheral electrode 26 is patterned on the insulating film 34 so as to be divided by the drain line DL. Then, the contact groove 3 formed in the insulating film 34
The interconnect electrode 36 and the peripheral electrode 26 are connected to each other by the drain metal DM formed together with the drain line DL in 4A. The interconnect electrode 36 can be formed by patterning at the same time when the gate electrode G of the TFT 24 is formed.

FIG. 5 is a sectional view taken along line bb of FIG.
The cross section of the portion where the peripheral electrode 26 crosses the gate line GL is shown. As shown in FIG. 5, the peripheral electrode 26 is formed on the gate line GL formed on the lower glass substrate 21 via the insulating film 34. The peripheral electrode 26 having such a structure
As described above, although it is divided at a portion that crosses the drain line DL, electrical connection is achieved by the interconnect electrode 36 and the drain metal DM at that portion, and a substantially frame-shaped peripheral electrode is formed. However, it can be formed so as to go around the periphery of the display area.

In this liquid crystal display device, light (natural light or the like) incident from the upper glass substrate 22 side is reflected by a reflecting plate 32 via an upper polarizing plate 33, a retardation plate 35, a liquid crystal 30, a lower polarizing plate 31 and the like. It is of a reflective type for displaying. The incident light is first linearly polarized in a predetermined direction by the upper polarizing plate 33, then appropriately polarized by the retardation plate 35, and travels toward the liquid crystal 30. Here, the liquid crystal 30 interposed between the pixel electrode 25 and the common electrode and the peripheral portion, that is, the peripheral electrode 26 and the common electrode 28 is disposed between the electrodes 25 and 28 and between the electrodes 26 and 2.
The light is appropriately polarized by this action, the light is appropriately polarized, is directly polarized by the lower polarizing plate 31, and is reflected by the reflecting plate 32. The reflected light is again transmitted through the lower polarizing plate 31, the liquid crystal 30, the phase difference plate 35, and the upper polarizing plate 33 in order to be polarized and displayed in color.
In such a liquid crystal display element, since color display is performed by the polarization action of the liquid crystal, the retardation plate, and the polarizing plate, a color filter for reducing the transmittance is unnecessary. Therefore,
Since display with high transmittance can be performed, incident light can be reflected to perform display with stronger color tone. In such a liquid crystal display element, since the potential difference between the common electrode 28 on the glass substrate 22 side and the peripheral electrode 26 can be determined by the voltage applied to the extraction terminal 26A, the colors and gradations displayed in each pixel portion can be determined. It is possible to change the color and gradation of the peripheral portion of the display area at any time according to the above, or according to the ambient brightness. Therefore, for example, when viewing the display outdoors, etc., when the light reflection of the display part is large and difficult to see,
The peripheral portion of the display area can be darkened (blackened). Conversely, when the surrounding area is dark, the peripheral portion of the display area can be controlled to be bright. As described above, in this embodiment, the frame pattern of the display area of the liquid crystal display element is in a desired state (color, gradation, etc.).
Therefore, it is possible to provide a display that is ergonomically easy to see.

In the above embodiment, the drain line D
Although the peripheral electrodes 26 on both sides of L were connected by the drain metal DM and the interconnect electrode 36, after forming the contact groove 34A as shown in FIG.
May be embedded in the contact groove 34A and directly connected to the interconnect electrode 36.

In the above-mentioned embodiment, the bottom gate type thin film transistor is used, but a top gate type thin film transistor can be similarly constructed as shown in FIG. 9 is a sectional view taken along line cc shown in FIG. 8, and FIG. 10 is a sectional view taken along line dd shown in FIG.

In the gate direction, that is, in the direction orthogonal to the drain line, the peripheral electrode 51 is insulated from the drain line DL via the gate insulating film 53, as shown in FIG. In the direction orthogonal to the line, as shown in FIG. 10, on both sides of the gate line GL on the interconnect electrode 54 formed integrally with the electrodes S and D by a metal made of the same material as the source electrode S and the drain electrode D. A contact groove 53A is provided in the corresponding gate insulating film 53, and the gate line G is made of a metal made of the same material as the gate line GL.
The gate metal GM formed together with L electrically connects the interconnect electrode 54 below the contact groove 53A and the peripheral electrode 51. Therefore, the peripheral electrode 51
Is insulated from the drain line DL and the gate line GL, and is connected across the gate line GL.

Further, as described above, the gate metal GM
Instead of directly using the
It may be embedded in A and connected to the interconnect electrode 54. Furthermore, in the above-described embodiment, one peripheral electrode is provided in the shape of a frame around one display area, but the present invention is not limited to this, and a single or a plurality of display areas may be provided between or around a plurality of display areas. Good. For example, as shown in FIG. 11, display regions P1, P2, and P3 are provided on the lower glass substrate 21, and peripheral electrodes 41, 42, 43, 44, 45, and 46 are provided around them as gate electrodes or source / drain electrodes. The same material is formed at once.

The display region P1 occupies the upper half of the lower glass substrate 21, and peripheral electrodes 41 surrounding the three sides and peripheral electrodes 42 and 43 are arranged on the sides connecting both ends of the peripheral electrode 41. The display area P2 includes the peripheral electrodes 42, 44, 46.
The display area P3 is surrounded by the peripheral electrodes 43, 45, 46.
It is surrounded by. Peripheral electrode terminals 41A, 42A, 44
A is gathered at the upper left of one side where each terminal of the drain line DL of the lower glass substrate 21 is extended, and the peripheral electrode terminal 4
3A, 45A, and 46A are gathered on the upper right side of one side surface of the lower glass substrate 21 where the terminals of the drain line DL are extended. From the viewpoint of electrical characteristics, it is preferable that the terminals of the peripheral electrodes be routed so as not to intersect the gate line and the drain line as much as possible.

Therefore, the peripheral electrodes 41 to 46 are connected to the signal drive circuit connected to the drain line DL. By dividing the peripheral electrode in this way,
The applied voltage can be reduced. In addition, when color display is performed depending on the orientation of the polarizing plate, the retardation plate, and the liquid crystal, the display color may be different due to a slight difference in applied voltage. Therefore, it is better to divide the peripheral electrodes for display. Color change is small. Further, in the above embodiment, since the peripheral electrode is divided according to the plurality of display regions,
Different colors can be displayed for each periphery of the display area.

In the above embodiment, since the display voltage can be applied to the peripheral electrodes at the timing of supplying the signal voltage to the drain electrodes for each row, each pixel electrode must hold the voltage for one frame period. On the other hand, since the peripheral electrodes may be held until the scanning voltage is applied to the next row or a plurality of rows, a large display area can be taken for the applied voltage. Therefore, since it is not necessary to increase the voltage applied to the peripheral electrodes at one time, it is not necessary to make the voltage generating circuit extremely large. Further, pixel electrodes may be provided in the peripheral electrodes in the portions parallel to the gate lines similarly to the display region, and the same signal voltage may be supplied from the drain lines DL only to that row for display.

Although the embodiment has been described above, the present invention is not limited to this, and various design changes accompanying the gist of the configuration can be made. For example, although the present invention is applied to the liquid crystal display device in which the liquid crystal is twist-aligned in the above embodiment, the DAP type, the super twisted nematic birefringence type,
A liquid crystal display element of light interference color type, homogeneous type, HAN type, color filter type, VAN type, CSH type, or color light source type may be used. Further, in the present embodiment, the reflective type in which the polarizing plates are provided on both outer sides of the liquid crystal is also possible, but the constitution may be such that the retardation plate or the lower polarizing plate is not used, and a backlight may be provided instead of the reflecting plate. . In addition to TN liquid crystal, ST
N-type, ferroelectric type, anti-ferroelectric type, and polymer dispersed type liquid crystals can be applied to the present invention. Furthermore, the display area and the peripheral portion may be in different liquid crystal modes. Further, although the thin film transistor is applied as the switching element in the above embodiment, the present invention is not limited to this, and it may be an MIM element or may be arranged on the upper glass substrate. Further, a simple matrix type liquid crystal display element can be applied to the present invention. When the simple matrix type liquid crystal display device is applied to the present invention as described above, the display electrode in the display region of one transparent substrate is a signal electrode, and the display electrode in the display region of the other transparent substrate is a scanning electrode. Further, in the above embodiment, segment display by static drive is also possible, and character display or blinking display may be used. Then, frame-shaped peripheral electrodes may be formed on the peripheral portions of the display regions of both transparent electrodes. The drive circuit of the liquid crystal display element may be directly provided on the glass substrate.

[0024]

As is apparent from the above description, according to the present invention, it is possible to display the color or gradation according to the setting in the peripheral portion of the display area, and it is possible to make a frame pattern of your choice. This has the effect of realizing a liquid crystal display element that is easy to see. In addition, by forming the peripheral electrode with the same material as the display electrode formed in the display area of the transparent substrate, there is an effect that the peripheral electrode can be easily formed without increasing the manufacturing process.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part of an embodiment of the present invention.

FIG. 2 is a plan view of a glass substrate provided with a switching element according to an embodiment of the present invention.

FIG. 3 is an enlarged plan view of an essential part of a glass substrate provided with a switching element according to an embodiment of the present invention.

4 is a sectional view taken along line aa of FIG.

5 is a sectional view taken along line bb of FIG.

FIG. 6 is a cross-sectional view of a main part of a glass substrate according to an example of the present invention.

FIG. 7 is a diagram showing settings of a polarizing plate, a retardation plate, and a liquid crystal according to an embodiment of the present invention.

FIG. 8 is an enlarged plan view of an essential part of a glass substrate provided with a switching element according to another embodiment of the present invention.

9 is a sectional view taken along line cc of FIG.

10 is a sectional view taken along line d-d of FIG.

FIG. 11 is a plan view of a glass substrate provided with a switching element according to still another embodiment of the present invention.

FIG. 12 is a cross-sectional view of a main part showing a conventional example.

[Explanation of symbols]

 21, 22 Glass Substrate 24 TFT 25 Pixel Electrode 26 Peripheral Electrode 28 Common Electrode 28A Peripheral Electrode Part 30 Liquid Crystal 31 Lower Polarizing Plate 32 Reflecting Plate 33 Upper Polarizing Plate 35 Phase Difference Plate

Claims (9)

[Claims] 1. A liquid crystal display device comprising a liquid crystal cell in which liquid crystal is sealed between a pair of substrates each having a display electrode provided in a display region on a surface opposite to each other. A liquid crystal display device having a peripheral electrode formed by 2. The liquid crystal display according to claim 1, wherein the display electrodes provided on one of the pair of substrates are arranged in a matrix, and switching elements are connected to the display electrodes, respectively. element. 3. The switching element includes a gate insulating film, a semiconductor layer and a gate electrode arranged to face each other with the gate insulating film interposed therebetween, and a source electrode and a drain electrode respectively connected to the semiconductor layer. 3. A thin film transistor provided, wherein the gate electrode is connected to a gate line connected to a scan driving circuit, and the drain electrode is connected to a drain line connected to a signal driving circuit. The liquid crystal display element described. 4. The peripheral electrode is insulated from the gate line and the drain line via the gate insulating film, and on the opposite side of a surface of the gate insulating film facing one of the gate line and the drain line. 4. The liquid crystal display device according to claim 3, wherein the source electrode, the drain electrode, and the gate electrode are continuously connected to each other by a connection electrode formed of the same material. 5. The peripheral electrode of a substrate different from the substrate provided with the switching element of the pair of substrates is formed of the same material as the display electrode.
The liquid crystal display element described. 6. The terminal of the wiring connected to the peripheral electrode of the substrate on which the thin film transistor is provided extends to one side surface of the substrate on which the terminal of the drain line is provided. Liquid crystal display device. 7. A polarizing plate is provided on each of the outer surfaces of the pair of substrates, and the liquid crystal between the peripheral electrodes changes the retardation according to the voltage applied to the peripheral electrodes to form an ellipse of the liquid crystal. 2. The liquid crystal display device according to claim 1, wherein the polarization effect is changed to change the color of light transmitted through the polarizing plate. 8. The liquid crystal display device according to claim 7, wherein at least one retardation plate is provided between the polarizing plates on both outer surfaces of the pair of substrates. 9. The liquid crystal display device according to claim 1, further comprising a reflection plate provided below the pair of substrates.