JP5397989B2 - Liquid crystal display - Google Patents

Description

The present invention relates to a liquid crystal display device. More specifically, one electrode includes two electrodes for controlling the alignment of a liquid crystal having a transmissive portion for performing transmissive display and a reflective portion for performing reflective display. The present invention relates to a liquid crystal display device provided on a substrate.

As a wide viewing angle liquid crystal panel, for example, FFS (Fringe Field Switching) method or IPS
There is an (In-Plane Switching) type liquid crystal panel. In these methods, both the pixel electrode and the common electrode are provided on the element substrate, and the alignment state is controlled by rotating liquid crystal molecules by controlling the electric field generated between the two electrodes.

A liquid crystal panel has both a transmissive type that displays using backlight light, a reflective type that displays using reflected external light, and a transmissive type and a reflective type in one pixel. Roughly divided into semi-transmission type.

JP 2003-270627 A JP 2004-198922 A

Conventional TN and ECB transflective types have insufficient contrast and a narrow viewing angle. The VA transflective type has a high contrast and can widen the viewing angle, but has a problem that the color changes at a low viewing angle.

In contrast to the TN method and ECB method, the FFS method and IPS method transflective type have good viewing angle characteristics, and the color change at a low viewing angle as seen in the VA method is very high. Few. However, in order to achieve both transmissive display and reflective display, it is necessary to attach a phase difference film or a phase difference plate, thereby causing a problem that the contrast is lowered. Furthermore, there is a problem that the liquid crystal display device becomes thicker than the transmission type of the FFS method or the IPS method.

The present invention provides a good display for a liquid crystal display device which has a transmissive portion for performing transmissive display and a reflective portion for performing reflective display in one pixel and includes two electrodes for controlling the alignment of liquid crystal on one substrate. The purpose is to obtain.

The liquid crystal display device according to the present invention, a liquid crystal sandwiched between the first substrate and the second substrate, and a reflecting unit for performing reflective display and the transmissive portion for performing transmissive display in one pixel, the A liquid crystal display device having one electrode and a second electrode on a first substrate, comprising a first polarizing plate on a side opposite to the liquid crystal on the first substrate, and a second polarization on a side opposite to the liquid crystal on the second substrate. A second electrode is provided on the second substrate facing the first substrate through the liquid crystal, the first electrode is provided across the transmission portion and the reflection portion, and the second electrode is in one direction of the first substrate. A slit extending in the transmission portion, and disposed in the transmission portion so as to face the first electrode through the insulating film, and the third electrode is arranged in the reflection portion so as to face the first electrode via the liquid crystal. The major axis of the liquid crystal molecules in the transmission part and the reflection part is substantially parallel to the surface of the first electrode, and the slit of the second electrode The initial orientation is substantially parallel to the extending direction, the orientation is controlled by the electric field between the first electrode and the second electrode in the transmission portion, and the orientation is controlled by the electric field between the first electrode and the third electrode in the reflection portion, and the reflection is performed. The retardation layer disposed in the portion is a half-wave plate, and the transmission axis of the first polarizing plate is the first in the dark display of the transmission portion where the potential difference between the first electrode and the second electrode is an off-voltage . It arrange | positions so that the light which injected into 1 polarizing plate may enter into a liquid crystal as polarization | polarized-light substantially orthogonal with respect to the major axis of the liquid crystal molecule of a liquid crystal.

With the above configuration, the reflection part can be controlled by the first electrode and the third electrode provided on the first substrate and the second substrate, and the transmission part is a semi-transmission type such as an FFS system having a wide viewing angle. Type liquid crystal display device can be realized. At this time, since the retardation layer is not disposed in the transmissive portion, deterioration of the contrast of the transmissive portion due to the retardation layer can be suppressed.

Further , it is preferable that the transmission axis of the first polarizing plate and the transmission axis of the second polarizing plate are arranged substantially orthogonally .
Further, phase difference layer is provided on the liquid crystal side of the second substrate, it is preferable that the 45 ° rotation of the polarization direction of the linearly polarized light incident from the second polarizing plate.

Further , it is preferable that the same potential is applied to the second electrode and the third electrode.

With the above configuration, 2 for controlling the orientation of the liquid crystal having a transmissive portion and a reflective portion in one pixel.
Good display can be obtained for a liquid crystal display device having one electrode on one substrate.

It is a schematic diagram explaining the liquid crystal display device which concerns on embodiment of this invention. It is a schematic diagram explaining the liquid crystal display device which concerns on embodiment of this invention. It is a schematic diagram explaining the other liquid crystal display device which concerns on embodiment of this invention.

  Embodiments according to the present invention will be described below in detail with reference to the drawings.

1 and 2 are schematic diagrams illustrating a liquid crystal display device 50 according to an embodiment of the present invention. The liquid crystal display device 50 includes a liquid crystal panel 60, a drive circuit 70 that drives the liquid crystal panel 60,
And a backlight device (not shown) disposed to face the liquid crystal panel 60. In FIG. 1 and the like, one pixel (also referred to as a dot, a subpixel, or the like) of the liquid crystal panel 60 is shown in a cross-sectional view, and only some elements are hatched to avoid complication of the drawing.

The liquid crystal panel 60 is a transflective liquid crystal panel including a transmissive portion 60T that performs transmissive display and a reflective portion 60R that performs reflective display in one pixel. The transmission part 60T and the reflection part 60
R is not only a two-dimensional region in a plan view of the pixel, but also the two-dimensional region of the liquid crystal panel 60 defined by projecting the two-dimensional region in the thickness direction of the liquid crystal panel 60, that is, the overlapping direction of substrates 100 and 200 described later. It shall also refer to a three-dimensional region.

Here, a case where the liquid crystal panel 60 performs transmissive display by an FFS (Fringe Field Switching) method and reflective display by an ECB (Electrically Controlled Birefringence) method is illustrated.

The liquid crystal panel 60 includes an element substrate 100, a counter substrate 200 facing the element substrate 100,
The liquid crystal (or liquid crystal layer) 300 provided between the substrates 100 and 200 is included. Note that liquid crystal molecules are schematically illustrated for the liquid crystal 300.

The element substrate 100 includes a light-transmitting substrate 112, and further includes a circuit layer 114, a planarizing film 116, on the inner side of the light-transmitting substrate 112, that is, on the liquid crystal layer 300 side with respect to the substrate 112. , The reflective film 118, the first electrode 120, the insulating film 122, the second electrode 124,
And an alignment film (not shown).

  The translucent substrate 112 is made of, for example, a transparent glass plate.

The circuit layer 114 is a layer in which various elements are formed and a circuit for driving a pixel is formed, and includes, for example, a pixel TFT (Thin Film Transistor) and various wirings.
Although details of the circuit are omitted here, various circuits are applicable. The circuit layer 114 is disposed on the translucent substrate 112 across the transmission part 60T and the reflection part 60R.

The planarization film 116 is made of, for example, an insulating and translucent resin, and is positioned on the circuit layer 114 so as to be closer to the liquid crystal layer 300 than the circuit layer 114. The planarizing film 116 is formed of the transmission part 6.
It extends over 0T and the reflective portion 60R. The surface of the planarizing film 116 on the counter substrate 200 side is flat in the transmissive portion 60T and is uneven in the reflective portion 60R. The uneven shape can be formed by various methods. For example, the planarization film 116 can be formed of a photoresist material, and can be formed by pattern exposure and development of the photoresist material.

The reflective film 118 is made of a material capable of reflecting external light (visible light) for reflective display, such as aluminum. The reflective film 118 is disposed on the reflective portion 60R and is disposed on the uneven surface of the planarizing film 116. The surface of the reflective film 118 on the counter substrate 200 side is the planarizing film 11.
6 has an uneven shape similar to the uneven surface.

The first electrode 120 is made of a light-transmitting conductive material such as ITO (Indium Tin Oxide). The first electrode 120 is disposed on the planarizing film 116 so as to cover the reflective film 118.
The first electrode 120 extends over the transmission part 60T and the reflection part 60R, that is, the transmission part 60.
It is an electrode common to T and the reflection part 60R. The surface of the first electrode 120 on the counter substrate 200 side is
It is flat in the transmission part 60T, and in the reflection part 60R, the reflection film 118 and the planarization film 116 are used.
The uneven surface is the same as the uneven surface.

Note that when the reflective film 118 has conductivity, the first electrode 120 may not cover the entire reflective film 118 as long as it is connected to the reflective film 118. That is, the first electrode 12
It is also possible to configure the part in the reflection part 60R of 0 by the reflection film 118.

In FIG. 1 and the like, the connection between the first electrode 120 and the drive circuit 70 is schematically illustrated for the sake of explanation. However, the application of a potential to the first electrode 120 is, for example, the pixel TFT in the circuit layer 114. Etc.

The insulating film 122 is made of, for example, silicon oxide, nitrogen silicon, or the like. Insulating film 12
2 is disposed on the flat surface of the first electrode 120 in the transmission part 60T. The surface of the insulating film 122 on the counter substrate 200 side is flat.

The second electrode 124 is made of a translucent conductive material such as ITO. Second electrode 12
4 is disposed on the insulating film 122 in the transmissive portion 60T and faces the first electrode 120 with the insulating film 122 interposed therebetween. That is, the first electrode 120, the insulating film 122, and the second electrode 1
24 are stacked in this order. Since both electrodes 124 and 120 are provided on the element substrate 100, they are located on the same side with respect to the liquid crystal layer 300. The second electrode 124 is provided with a slit 126 at a portion facing the first electrode 120. Here, the case where the slit 126 extends in a substantially vertical direction in the drawing is illustrated. An electric field ET caused by a potential difference between the first electrode 120 and the second electrode 124 is generated through the slit 126 and the insulating film 122 (FIG. 2).
reference). The alignment state in the transmission part 60T of the liquid crystal 300 is controlled by the electric field ET.

Note that in FIG. 1 and the like, the connection between the second electrode 124 and the drive circuit 70 is schematically illustrated for the sake of explanation, but the application of a potential to the second electrode 124 is performed by, for example, wiring in the circuit layer 114. Done through.

An alignment film (not shown) is disposed so as to cover the second electrode 124, the insulating film 122, and the first electrode 120, and is in contact with the liquid crystal 300.

The counter substrate 200 includes a light-transmitting substrate 212, and further, a color filter 214 on the inner side of the light-transmitting substrate 212, that is, on the liquid crystal 300 side with respect to the substrate 212,
The phase difference layer 216, the third electrode 218, and an alignment film (not shown) are included.

  The translucent substrate 212 is made of, for example, a transparent glass plate.

The color filter 214 is made of, for example, a dyed resin, and includes a transmission part 60T and a reflection part 6.
It is arranged on the translucent substrate 212 over 0R. The color filter 214 colors the backlight light incident from the element substrate 100 side and the external light incident from the counter substrate 200 side, and the pixels are lit in a predetermined color. The color of the color filter 214 is set according to the display color (single color) of each pixel. Note that one unit composed of adjacent pixels of a plurality of colors is called a pixel or the like, and the one unit may be called a pixel.

Here, the phase difference layer 216 exemplifies a case corresponding to a half-wave plate (or a half-wave plate (half wavelength) plate). In this case, the polarization direction of the linearly polarized light can be rotated 45 ° clockwise (or counterclockwise) by the retardation layer 216. The retardation layer 216 is located closer to the liquid crystal layer 300 than the color filter 214, and the color filter 2 is formed in the reflection unit 60R.
14 is arranged. In this case, the retardation layer 216 is built in the liquid crystal panel 60. Here, the term “built-in” refers to an arrangement form arranged between the translucent substrates 112 and 212. At this time, for example, it is considered that the above-described pixel TFT and the like are also incorporated in the liquid crystal panel 60.

The retardation layer 216 can be formed using, for example, UV (ultraviolet) curable liquid crystal (liquid crystal curable with ultraviolet). More specifically, an alignment film (not shown) is formed on the color filter 214, and a liquid UV curable liquid crystal is applied on the alignment film.
) To cure, the retardation layer 216 can be formed. In this case, the retardation layer 216 includes a UV curable liquid crystal, or further includes the alignment film. The alignment film controls the alignment of the UV curable liquid crystal and does not regulate the alignment of the liquid crystal 300. Various alignment films can be used as the alignment film for the UV curable liquid crystal. For example, a photo-alignment film that generates liquid crystal alignment ability by light irradiation can be used, and rubbing is not necessary according to the photo-alignment film. The UV curable liquid crystal functions as a retardation plate by applying UV curing (irradiating with UV and curing). The phase difference can be adjusted by changing the thickness of the UV curable liquid crystal.

The third electrode 218 is made of a light-transmitting conductive material such as ITO. Third electrode 21
8 is located on the liquid crystal layer 300 side of the phase difference layer 216, is disposed on the phase difference layer 216 in the reflective portion 60 </ b> R, and faces the first electrode 120 through the liquid crystal layer 300. That is,
The third electrode 218 is located on the opposite side of the liquid crystal 300 from the first electrode 120. Third
The alignment state in the reflective portion 60R of the liquid crystal 300 is controlled by the electric field ER caused by the potential difference between the electrode 218 and the first electrode 120 (see FIG. 2).

The same potential as that of the second electrode 124 is applied to the third electrode 218. This form of potential application is schematically illustrated in FIG. 1 and the like in the case where the wiring from the drive circuit 70 branches to reach both electrodes 218 and 124. In place of this example, a branch is provided in the liquid crystal panel 60 so that both electrodes 124,
You may comprise in the state which can apply the same electric potential to 218. For example, the electrodes 218 and 124 may be connected in the liquid crystal panel 60 using conductive particles or the like, and the potential from the drive circuit 70 may be applied to one of the electrodes 124 and 218. Further, wiring from the driving circuit 70 may be provided for both electrodes 218 and 124, respectively, and the same potential may be output from the driving circuit 70 to each wiring.

An alignment film (not shown) is disposed so as to cover the third electrode 218, the retardation layer 216, and the color filter 214, and is in contact with the liquid crystal 300.

The liquid crystal panel 60 further includes polarizing plates 128 and 220. Polarizing plate 12
8 is arranged outside the element substrate 100, that is, on the side opposite to the liquid crystal layer 300 with respect to the translucent substrate 112. The polarizing plate 220 is disposed outside the counter substrate 200, that is, on the side opposite to the liquid crystal layer 300 with respect to the translucent substrate 212.

The drive circuit 70 is connected to the electrodes 120, 124, 218 and connected to the electrodes 120, 124, 21.
8 includes various elements for generating, transmitting, and the like, the potential applied to 8. The various elements are externally attached to, built in, or mounted on the liquid crystal panel 60, and include, for example, pixel TFTs in the circuit layer 114. The drive circuit 70 generates the applied potential and applies it to the electrodes 120, 124, and 218 at a predetermined timing.

Next, an example of the operation of the liquid crystal display device 50 will be described with reference to FIGS. 1 and 2. Here, a case where the transmissive display is performed by the FFS method and the reflective display is performed by the ECB method as described above is illustrated. The liquid crystal 300 has, for example, positive dielectric anisotropy and refractive index anisotropy (
Δn (also called birefringence) is 0.1.

The liquid crystal panel 60 is configured such that when the potential difference between the first electrode 120 and the second electrode 124 is an OFF voltage, the transmissive display is a dark display having the lowest luminance, and the first When the potential difference between the electrode 120 and the third electrode 218 is an off voltage, the reflective display is configured to be a dark display (see FIG. 1). Note that the luminance for the transmissive display corresponds to the transmittance, and the luminance for the reflective display corresponds to the reflectance. The dark display is also called a dark state, black display, or the like. The state with the highest luminance is called bright display. The bright display is also called a bright state, white display, or the like. A voltage that realizes dark display or bright display and that hardly generates the electric fields ET and ER is called an off voltage. On the other hand, it is a voltage that realizes dark display or bright display and is compared to when the off voltage is applied. Turn on the voltage that generates large electric fields ET and ER (O
N) Let's call it voltage.

For this reason, here, both the transmission part 60T and the reflection part 60R are configured in a normally black system, and the entire pixel is also configured in a normally black system. Such a configuration includes the material of the liquid crystal 300, the alignment state of the liquid crystal 300 when applying an off voltage (so-called initial alignment state), the rubbing direction of the alignment film, the characteristics and arrangement of the polarizing plates 128 and 220, and the retardation layer 216, and the like. It is possible by adjusting.

In the liquid crystal display device 50, since the same potential is applied to the second electrode 124 and the third electrode 218, the transmissive portion 60T and the reflective portion 60R are simultaneously darkly displayed by applying the off voltage. That is, the entire pixel is darkly displayed. On the other hand, the transmissive part 60T and the reflective part 60R can be simultaneously brightly displayed by applying the ON voltage, and at this time, the entire pixel is brightly displayed (FIG. 2).
reference).

  A more specific example will be described below.

For example, when the off voltage is applied, the liquid crystal 300 is formed in the transmissive part 60T and the reflective part 60R.
Are initially aligned so that the major axis of the liquid crystal molecules is substantially parallel to the surfaces of the electrodes 120, 124, and 218 and substantially parallel to the extending direction of the slit 126 (and therefore aligned in the substantially vertical direction of the drawing). Note that the rubbing direction is set to be the same between the transmission portion 60T and the reflection portion 60R. Further, the polarizing plate 128 is arranged so that the transmission axis is substantially orthogonal to the long axis of the liquid crystal molecules in the initial alignment state. In addition, the polarizing plate 220 is disposed so that the transmission axis of the polarizing plate 128 and the transmission axis are substantially orthogonal (so-called orthogonal arrangement).

In this case, in the transmissive display, the backlight light incident from the element substrate 100 side becomes linearly polarized light substantially orthogonal to the major axis of the liquid crystal molecules by the polarizing plate 128. According to the relationship between the polarization direction of the linearly polarized light and the alignment direction of the liquid crystal molecules, the birefringence effect of the liquid crystal 300 is hardly received. Therefore, the linearly polarized light reaches the polarizing plate 220 while maintaining the polarization state. However, since the linearly polarized light is polarized in a direction substantially orthogonal to the transmission axis of the polarizing plate 220, it cannot be transmitted through the polarizing plate 220, and as a result, the transmissive display becomes a dark display.

For reflective display, external light incident from the counter substrate 200 side becomes linearly polarized light substantially parallel to the long axis of the liquid crystal molecules by the polarizing plate 220, and the polarization direction is rotated by 45 ° by the above action of the retardation layer 216. It enters the liquid crystal layer 300 in the polarization state. The liquid crystal layer 300 of the reflective portion 60R is adjusted so as to act in the same manner as a quarter wavelength (quarter wavelength) plate by utilizing its birefringence. In this case, the liquid crystal layer 300 converts the linearly polarized light into clockwise (or counterclockwise) substantially circularly polarized light. The external light that is substantially circularly polarized by the liquid crystal layer 300 is reflected by the reflective film 118,
For linearly polarized light that has passed through the liquid crystal layer 300 and entered the liquid crystal layer 300 from the retardation layer 216, 9
The light is linearly polarized light rotated by 0 °, and the polarization direction is rotated by −45 ° by the retardation layer 216 to reach the polarizing plate 220. However, the linearly polarized light returning to the polarizing plate 220 is polarized in a direction substantially orthogonal to the transmission axis of the polarizing plate 220. Therefore, it cannot pass through the polarizing plate 220, and as a result, the reflective display becomes a dark display.

On the other hand, when the off voltage is changed to the on voltage, the transmissive display is removed from the dark display, and the reflective display is also removed from the dark display (see FIG. 2). Note that the luminance of the transmissive display and the reflective display increases as the applied voltage increases.

In the transmissive portion 60T, the liquid crystal molecules in the vicinity of the element substrate 100 are aligned in a direction substantially parallel to the surfaces of the electrodes 120 and 124 and substantially perpendicular to the extending direction of the slit 126 by applying the on voltage. On the other hand, the liquid crystal molecules near the counter substrate 200 remain in the initial alignment state. For this reason, the liquid crystal molecules in the transmission part 60T are aligned in a state twisted by 90 ° around the normal line of the electrodes 124 and 120 as a whole. In this case, the backlight light that has been linearly polarized by the polarizing plate 128 is polarized in a direction substantially parallel to the major axis of the liquid crystal molecules in the vicinity of the element substrate 100, and is rotated (rotated) according to the twisted alignment state of the liquid crystal molecules. When the light reaches the polarizing plate 220, the light becomes linearly polarized light substantially parallel to the major axis of the liquid crystal molecules near the counter substrate 200. Since the linearly polarized light is polarized substantially parallel to the transmission axis of the polarizing plate 220, the transmissive display becomes bright.

In the reflection portion 60R, the liquid crystal molecules are aligned in a direction substantially orthogonal to the surfaces of the electrodes 120 and 218 by applying the on-voltage. External light incident from the counter substrate 200 side returns to the polarizing plate 220 through the same path (optical path) as in dark display, but is almost affected by the birefringence effect of the liquid crystal 300 according to the alignment state. Absent. For this reason, the external light that has returned to the polarizing plate 220 is subjected to a rotation operation in the polarization direction in the retardation layer 216 twice in total, resulting in linearly polarized light that is substantially parallel to the transmission axis of the polarizing plate 220. . Therefore, the light passes through the polarizing plate 220, and as a result, the reflective display becomes a bright display.

The case of dark display and bright display has been described above, but it is also possible to perform so-called halftone display at a level between dark display and bright display by controlling the magnitude of the applied voltage.

According to the above configuration, since the transmissive part 60T is an FFS system and the reflective part 60R is an ECB system, good display can be obtained in both reflective display and transmissive display. Moreover, when it is set as the structure which forms a phase difference layer in the reflection part of an inner surface, it is not necessary to stick a phase difference plate on an outer surface,
The liquid crystal panel can be made thinner than other transflective types. Furthermore, since the retardation layer 216 also serves as a layer for narrowing the cell gap of the reflective portion 60R than the cell gap of the transmissive portion 60T, the manufacturing process can be reduced.

In addition, since the reflection part 60R is configured by the ECB method having a higher reflectance than the FFS method,
Compared with the case where both the transmissive part 60T and the reflective part 60R are configured by the FFS method, a reflective display with high luminance can be obtained.

Further, since the FFS method is not adopted for the reflecting portion 60R, even when the uneven surface is formed on the planarizing film 116, it is not necessary to form the electrode 124 having the slit 126 on the uneven surface. . For this reason, there is no problem of slit patterning on the uneven surface, and a good reflective display can be obtained. For transmissive display, wide viewing angle by FFS method,
High contrast and the like are realized.

In the FFS method, an ITO film or the like is generally formed on the outer surface of the counter substrate to shield an electric field from the outside. However, according to the above configuration, it is not necessary to provide a shield structure outside. This is because the third electrode 218 of the counter substrate 200 has a shielding action. Even if the counter substrate 200 is not provided over the entire surface, it is possible to obtain a shielding action by the third electrode 218.

In addition, since the retardation layer 216 is not provided in the transmissive portion 60T, unlike the case where the transmissive portion 60T and the reflective portion 60R are externally attached without being distinguished from each other, F
A wide viewing angle, high contrast, etc. are ensured by the FS method.

Moreover, the cell gap in the reflection part 60R is narrowed by the retardation layer 216 more than the cell gap in the transmission part 60T (so-called multigap structure). For example, the transmission part 60T
The cell gap of the reflection part 60R is 1.4 μm.
Therefore, the cell gap can be adjusted between the transmission part 60T and the reflection part 60R without using a separate top coat layer. For example, the cell gap of the reflection part 60R can be adjusted to a value suitable for the ECB method.

In addition, although the case where the transmissive display is performed by the FFS method is illustrated above, the transmissive display is IP
It is also possible to adopt a configuration that is performed by an S (In-Plane Switching) method. In the case of the IPS method, as shown in FIG. 3, the first electrode 120 and the second electrode 124 are arranged on the planarizing film 116, that is, in the same layer in the transmission part 60T. FIG. 3 illustrates a state in which the entire pixel is in bright display.

Also, it is possible to configure a normally white type by arranging the polarizing plates 128 and 220 so that their transmission axes are substantially parallel to each other.

50 ... Liquid crystal display device, 60T ... Transmission part, 60R ... Reflection part, 100 ... Element substrate, 120 ...
1st electrode, 124 ... 2nd electrode, 200 ... Counter substrate, 216 ... Retardation layer, 218 ... 3rd electrode, 300 ... Liquid crystal, ET, ER ... Electric field.

Claims (4)

The liquid crystal sandwiched between the first substrate and the second substrate has a transmissive portion for performing transmissive display in one pixel and a reflective portion for performing reflective display, the a first electrode and a second electrode A liquid crystal display device provided on the first substrate,
A first polarizing plate on the opposite side of the first substrate from the liquid crystal;
A second polarizing plate on the opposite side of the second substrate from the liquid crystal;
A third electrode on the second substrate facing the first substrate via the liquid crystal;
The first electrode is provided across the transmissive part and the reflective part, and the second electrode has a slit extending in one direction of the first substrate, and the insulating film is interposed in the transmissive part via an insulating film. Arranged to face the first electrode, the third electrode is arranged to face the first electrode via the liquid crystal in the reflection portion,
The liquid crystal is initially aligned so that the major axis of the liquid crystal molecules in the transmissive part and the reflective part is substantially parallel to the surface of the first electrode and substantially parallel to the extending direction of the slit of the second electrode. And the orientation is controlled by the electric field between the first electrode and the second electrode in the transmission part, and the orientation is controlled by the electric field between the first electrode and the third electrode in the reflection part.
The retardation layer disposed in the reflecting portion is a half-wave plate,
The transmission axis of the first polarizing plate is such that light incident on the first polarizing plate is a liquid crystal molecule of the liquid crystal in the dark display of the transmissive portion where the potential difference between the first electrode and the second electrode is an off voltage. A liquid crystal display device disposed so as to be incident on the liquid crystal as polarized light substantially perpendicular to the major axis. The liquid crystal display device according to claim 1,
A liquid crystal display device , wherein a transmission axis of the first polarizing plate and a transmission axis of the second polarizing plate are arranged substantially orthogonal to each other . The liquid crystal display device according to claim 1 or 2,
  The liquid crystal display device, wherein the retardation layer is provided on the liquid crystal side of the second substrate and rotates the polarization direction of linearly polarized light incident from the second polarizing plate by 45 °. The liquid crystal display device according to any one of claims 1 to 3,
A liquid crystal display device, wherein the same potential is applied to the second electrode and the third electrode.

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