JP2003185997A - Liquid crystal display device and electronic appliance - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize a bright display and to provide a liquid crystal display device with excellent visibility by increasing reflected light quantity in a direction of user's visual line in a reflective or transflective liquid crystal display device. <P>SOLUTION: The liquid crystal display device comprises a liquid crystal layer 4 held between upper and lower substrates 3, 2 placed opposite to each other, an upper polarizing layer 13 and a lower reflection polarizing layer 6 respectively disposed on the upper and lower sides of the liquid crystal 4 wherein the lower reflection polarizing layer 6 is formed by laminating prism shaped dielectric interference films consisting of a plurality of pairs of continuously formed slope parts with wedge shaped cross sections and angles which the slope parts of the edge part side in a direction of distinct vision out of the two paired slope parts form with the lower substrate 2 vary in the direction of distinct vision. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device and an electronic device, and more particularly to a structure provided with a reflective polarizing layer having a triangular-wave prism shape, which can further improve the luminance in the direction of the line of sight of the user. The present invention relates to a liquid crystal display device that is made possible.

[0002]

2. Description of the Related Art Reflective liquid crystal display devices have low power consumption because they do not have a light source such as a backlight, and have been widely used in various portable electronic devices and auxiliary display parts of devices. However, there is a problem that it is difficult to visually recognize the display in a dark place because the display is performed by using external light such as natural light or illumination light. Therefore, there has been proposed a liquid crystal display device in which outside light is used in a bright place like a normal reflection type liquid crystal display device, but in a dark place the display can be visually recognized by an internal light source. In other words, this liquid crystal display device employs a display system that has both a reflective type and a transmissive type. In the meanwhile, it is possible to make a clear display even when the surroundings are dark. Hereinafter, in this specification, this type of liquid crystal display device is referred to as a “semi-transmissive reflective liquid crystal display device”.

As one form of the semi-transmissive reflection type liquid crystal display device, a liquid crystal display device having the structure shown in FIG. 12 has been proposed. The liquid crystal display device 200 shown in this figure has a liquid crystal layer 203 sandwiched between a pair of transparent substrates 201 and 202.
A reflective polarization layer 204 is provided on the lower substrate 201, a stripe-shaped scanning electrode 208 made of a transparent conductive film such as ITO is formed thereon, and an alignment film 207 is formed so as to cover the scanning electrode 208. On the other hand, a color filter 209 is formed on the upper substrate 202, a flattening film 211 is stacked thereon, and a signal electrode 212 made of a transparent conductive film such as ITO is formed on the flattening film 211 and a scanning electrode 208.
The alignment film 213 is formed in a stripe shape in a direction orthogonal to the signal electrode 212 and covers the signal electrode 212. Further, on the outside of the upper substrate 202, the front scattering plate 218, the retardation plate 219, and the upper polarizing plate 2 are arranged in this order from the upper substrate 202 side.
14 are arranged. Further, the backlight 217 is arranged on the lower surface side of the lower substrate 201. The X direction in the drawing indicates the clear viewing direction.

Here, FIG. 13 is a side sectional view partially showing the reflective polarizing layer 204 and the lower substrate 201 shown in FIG. As shown in this figure, the reflective polarization layer 204 has a structure in which dielectric interference films 204a having a prism shape with a triangular wave cross section are laminated, and for example, a layer made of Si and SiO.
Layers of ₂ are laminated alternately (three layers in the figure).

In the liquid crystal display device 200 having the above structure, when displaying in the reflection mode, the upper substrate 202 is used.
Light incident from above the liquid crystal layer 20 from the upper substrate 202.
3 to reach the reflective polarization layer 204, is reflected by the reflective polarization layer 204, returns to the upper substrate 202 side, and reflective display is performed. Further, in the case of performing display in the transmission mode, of the light emitted from the backlight 205 and transmitted through the lower substrate 201, the reflective polarization layer 20.
The light parallel to the transmission axis of No. 4 is transmitted and used for display. Thus, the liquid crystal display device 2 described above
According to No. 00, when the outside light or the light of the backlight 217 is used for display, conversion from circularly polarized light to linearly polarized light or conversion from linearly polarized light to circularly polarized light does not occur, and thus the light loss due to this conversion does not occur. However, a relatively bright display is possible.

[0006]

However, although the liquid crystal display device described above has a high light reflectance, it has been found that the display in the reflection mode is not so bright. Therefore, the present inventor has made detailed investigations on the reflection state of light on the reflective polarizing layer 204 in the liquid crystal display device 200, and has obtained the following findings. That is, in the example of FIG. 13, the reflective polarizing layer 204 has a triangular wave-shaped prism shape, and a plurality of pairs of slope portions 204A and 204B having a wedge-shaped cross section,
It is formed continuously along the clear view direction (X direction in the figure). The angle formed by the slopes 204A and 204B and the lower substrate 201, that is, the inclination angle is 4
It is set at 5 °. Therefore, a part (s wave) of the light Lp incident from the normal direction of the lower substrate 201 is reflected by the slope portion 204A and becomes light toward the slope portion 204B, and a part (p
Wave) is transmitted and becomes light toward the lower substrate 201. Then, the reflected light (s wave) is reflected by the slope portion 204B and becomes light directed in the direction normal to the lower substrate 201, which is used for display. Similarly, the light Ls incident from above the lower substrate 201 is also reflected in the order of the slope portions 204A and 204B, and is emitted in the opposite direction to the incident direction. Therefore, in order to emit a large amount of light in the line-of-sight direction of the user, the incident direction of light and the line-of-sight direction of the user need to coincide with each other. However, in such an arrangement, external light is incident from the back of the user, so the incident light is blocked by the user in some cases, and the display becomes darker.

The present invention has been made in view of the above circumstances, and increases the amount of reflected light in the direction of the user's line of sight in a liquid crystal display device provided with a reflective polarizing layer having a triangular-wave prism shape. One of the objects is to provide a liquid crystal display device which realizes bright display and has excellent visibility. Another object of the present invention is to provide an electronic apparatus including the liquid crystal display device having the above-mentioned excellent characteristics.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the inventors of the present invention, in the above-mentioned Japanese Patent Application No. 2001-279760, form a pair of inclined angles of the inclined surface portions of the lower reflective polarizing layer. We proposed different configurations for the two slopes. That is, by forming the reflective polarizing layer into an inclined prism shape, the incident direction of external light and the emitting direction of reflected light are made different, and the emitting direction of the reflected light is made to coincide with the line-of-sight direction of the user. Thus, the amount of light in the line of sight of the user is increased.

FIG. 10 is an explanatory view showing a light path when a reflective polarizing layer having such a structure is provided on a lower substrate which constitutes a liquid crystal display device, and a lower reflective polarizing layer (reflective polarizing layer) 14 is shown.
4 is a diagram showing a partial cross section of the lower substrate (substrate) 140. FIG. As shown in this figure, the lower reflective polarization layer 144 is formed with a plurality of pairs of slope portions 144A and 144B having a wedge-shaped cross section, which are periodically and continuously formed along the clear viewing direction (X direction in the drawing). The two slope portions 14 having a wedge-shaped cross section
The inclination angles α and β of 4A and 144B are different from each other. According to this configuration, the incident direction of external light and the outgoing direction of the light reflected by the lower reflective polarization layer 144 can be made different, and therefore, as in the liquid crystal display device shown in FIGS. The incident direction and the outgoing direction of the reflected light do not match. Therefore, the display does not become dark due to the external light being blocked by the user. Further, by setting the inclination angles α and β to appropriate angles, the direction of emitted light with respect to the incident direction of external light can be controlled, and the amount of light visually recognized by the user can be increased. In FIG. 10, reference numerals 141 and 142 respectively denote different layers made of a dielectric interference film.

However, in the liquid crystal display device provided with such a tilted prism-shaped reflective polarizing layer,
The larger the display screen, the larger the variation in brightness in the clear viewing direction. For example, FIG. 11 shows the lower reflective polarizing layer (reflective polarizing layer) 1 shown in FIG.
FIG. 3 is a schematic configuration diagram schematically showing an overall liquid crystal display device including 44 on a lower substrate 140. In this liquid crystal display device, in the lower reflective polarization layer 144, a plurality of pairs of slope portions 144A and 144B having a wedge-shaped cross section are periodically formed along the clear view direction, and the clear view direction is the vertical direction of the display screen. It is arranged to match. The liquid crystal display device of this figure is different from the liquid crystal display device 200 shown in FIG. 12 only in the shape of the lower reflective polarization layer, and the other configurations are the same, but for convenience, the lower substrate 140 and the lower reflective polarization layer are used. Only the layer 144 and the upper substrate 150 are shown, and other members are not shown.

In the liquid crystal display device of this example, the inclination angles α and β of the inclined surface portions 144A and 144B in the lower reflective polarization layer 144 are 30 ° with respect to the normal direction of the upper substrate 150 from obliquely above the display screen. A part of the light L1 incident at the incident angle is reflected by the slope portions 144A and 144B,
The emitted light L2 is configured to be emitted in a direction substantially coincident with the normal line direction of the upper substrate 150. That is, the emission direction of the emitted light L2 reflected by the lower reflective polarization layer 144 and emitted from the upper substrate 150 is constant regardless of the upper side or the lower side of the display screen. However, the angle formed by the direction of the line of sight of the user and the direction of the normal to the upper substrate 150 is not necessarily constant over the entire area of the display screen. For example, as shown in FIG. 11, when the user looks at the screen, the eye position is below the center of the screen (right side in the drawing), and the line-of-sight direction is the upper substrate 150.
When it is almost the same as the normal direction of
A bright display can be obtained because the emission direction of the reflected light and the user's line-of-sight direction are substantially the same. The angle difference A between the and becomes large, and the display looks dark.

Therefore, the present invention adopts the following configuration in order to improve the nonuniformity of the brightness in the display screen. That is, the liquid crystal display device of the present invention is a liquid crystal display device in which a liquid crystal layer is sandwiched between an upper substrate and a lower substrate facing each other, and an upper polarizing layer and a lower reflective polarizing layer above and below the liquid crystal layer. The lower reflective polarization layer is formed by laminating prism-shaped dielectric interference films in which a plurality of pairs of inclined surface portions having a wedge-shaped cross section are continuously formed, and the lower reflection polarizing layer is formed of two prisms. The slope angle of the slope portion on the one end side in the clear view direction of the slope portion changes in the clear view direction.

According to the present invention, the reflection polarizing layer formed by laminating the dielectric interference films in the prism shape has the specific shape as described above, so that one end portion in the clear viewing direction (X direction) is formed. And the other end, the emission direction of the light reflected by the reflective polarizing layer can be different. As a result, the emission direction of the reflected light can be made to coincide with the line-of-sight direction of the user at both the upper side and the lower side of the display screen,
The angle difference A between the emission direction of the emission light L2 and the line-of-sight direction of the user, which has occurred in the configuration shown in FIG. 11, can be reduced. Therefore, the amount of reflected light in the direction of the user's line of sight is
Since it can be efficiently increased on the entire display screen,
It is possible to obtain a liquid crystal display which is bright and has good brightness uniformity in the display screen. In the present specification,
The inclination angle of the inclined surface portion is an angle formed by the inclined surface portion and a plane parallel to the display surface of the liquid crystal display device, and can be represented by, for example, an angle formed by the lower substrate and the inclined surface portion. The operation of the liquid crystal display device of the present invention will be described in detail below with reference to FIGS. 4 and 5.

FIG. 4 is a sectional view schematically showing an example of the liquid crystal display device of the present invention. Liquid crystal display device 16 of this figure
0 is different from the liquid crystal display device 200 shown in FIG. 12 only in the shape of the lower reflective polarizing layer 162, and the other configurations are the same, but for convenience, the lower substrate 161 and the lower reflective polarizing layer 16 are provided.
2, only the upper substrate 163 is shown, and other members are omitted. Further, FIG. 5 is an enlarged perspective view of the lower reflective polarization layer 162. The lower reflective polarization layer 162 has a plurality of pairs of slope portions 162A and 162B having a wedge-shaped cross section, which are continuously formed in the clear viewing direction (X direction in the drawing).
Then, the angles (tilt angles β1, β2 ...) Between the inclined surface portion 162B on the one end side in the clear view direction and the lower substrate 161 gradually increase from one end to the other end in the clear view direction. In addition, the slope portion 162A and the lower substrate 161 on the other end side in the clear view direction
The angle (tilt angle α) formed by and is constant.

In this example, the reflective polarizing layer 162 has a plurality of layers 171 and 172 made of a dielectric interference film alternately formed on a resin layer 173 formed on a flat substrate 161 in parallel triangular columns. It is a so-called three-dimensional photonic crystal layer formed by stacking. As described above, the photonic crystal having the structure in which the prism-shaped layers are laminated has anisotropy in light propagation characteristics, and when natural light is incident from the upper surface side in the drawing, the natural light The component Et perpendicular to the stripe-shaped groove of the reflective polarization layer 162 is transmitted through the reflective polarization layer 162, and the component Er parallel to the groove.
Is supposed to be reflected. That is, the reflective polarizing layer 162 shown in this figure has a reflection axis parallel to the groove direction and a transmission axis perpendicular to the groove direction. The light Et transmitted through the reflective polarizing layer 162 becomes polarized light perpendicular to the groove of the reflective polarizing layer 162, and the reflected light Er becomes polarized light parallel to the groove.

The stacking pitch D of the layers 171 and 172 is
It is appropriately adjusted to an optimum value according to the desired characteristics of the reflective polarizing layer 162. That is, the reflective polarizing layer 162 can control its transmittance (reflectance) by the number of layers of the layers 171 and 172, and by reducing the number of layers, the reflective axis (direction of the groove of the reflective polarizing layer 162) can be adjusted. It is possible to increase the transmittance of light of parallel components and reduce the reflectance. However, when a predetermined number of stacked layers or more are stacked, the component parallel to the reflection axis is totally reflected. In the present invention, in order for the reflective polarizing layer 162 to satisfy the required optical characteristics, the shape of the resin layer 173 formed on the lower substrate 161 is such that the allowable range of height change is within ± 10%, Is designed to satisfy the condition that the allowable range of change in the pitch P is within ± 20%.

In FIG. 5, a resin layer 173 having a triangular cross section made of a photocurable or thermosetting resin is provided on the surface of a flat substrate 161, and the dielectric layer 173 is formed on the resin layer 173. The case where the body interference films 171 and 172 are laminated to form the reflective polarization layer 162 has been described. However, the dielectric interference film may be laminated to form a reflective polarization layer on a substrate in which grooves are periodically formed on the surface. You can also

As shown in FIG. 4, for example, on the upper side of the display screen (left side of the figure), the light incident on the upper substrate 163 at the incident angle θ _i is incident on the inclined surface portion 162A having the inclination angle α. Incident at θ ₁ and a part (s wave) thereof is reflected by the inclined surface portion 162A, and an inclined surface portion 162B having an inclination angle β1.
The light is directed toward the lower substrate 161 and is partly transmitted through the inclined surface 162A to be directed toward the lower substrate 161 (p wave). Next, the light incident on the inclined surface portion 162B at the incident angle θ ₂ is also partially reflected and partially transmitted. Then, the light reflected by the inclined surface portion 162B is emitted above the lower reflective polarization layer 162 as emitted light. On the other hand, on the lower side (right side of the figure) of the display screen, the light incident on the upper substrate 163 at the incident angle θ _i is incident on the inclined surface portion 162A having the inclination angle α at the incident angle θ ₁ , and the inclined surface Part (s wave) is reflected by the portion 162A, and the slope portion 162 having the inclination angle β3.
Go to B. This light enters the inclined surface portion 162B at an incident angle θ ₃ , a part of the light is reflected, and the light is emitted above the lower reflection polarization layer 162 as emission light. In this way, the upper substrate 16
Even the incident angle theta _i are the same for the 3, the inclined surface portion inclination angle β1 of 162B that reflects light upwardly of the lower reflective polarization layer 162, .beta.2, for .beta.3 ... are different, to the inclined surface portion 162B Are different from each other (for example, θ ₂ and θ ₃ ), and as a result, the angle formed between the upper substrate 163 and the emission direction of the light that is reflected by the inclined surfaces 162B and emitted from the liquid crystal display device 160 is: Each is different.

Therefore, of the two slope portions 162A, 162B forming a pair in a wedge-shaped cross section, the slope angle α of the slope portion 162A on the side where light is incident is set to an appropriate angle, and this incidence is performed. By setting the inclination angles β1, β2, β3, ... Of the inclined surface portion 162B that reflects the light reflected by the inclined surface portion 162A on the side toward the upper side of the lower reflective polarization layer 162 to an appropriate angle individually, The emission direction of the reflected light with respect to the incident direction can be controlled for each individual sloped portion 162B. This makes it possible to match the emission direction of the light emitted from the liquid crystal display device with the line-of-sight direction of the user in the entire area of the display screen, thereby increasing the amount of light visually recognized by the user and maintaining the same reflectance. Even if there is, a brighter display can be obtained and the in-plane uniformity is improved.

By the way, as described above, the lower reflective polarizing layer 1
When the light incident on 62 is reflected by the inclined surfaces 162A and 162B, a part of the light is transmitted, so that the light is reflected in order to improve the display brightness in the reflection mode. It is preferable to increase the amount of light as much as possible. Specifically, the inclination angle α is set so that the incident angle θ ₁ on the inclined surface portion 162A on which the external light is incident becomes the Brewster's angle (polarization angle), and the incident angle θ ₁ is directed to the upper side of the lower reflective polarizing layer 162. By setting the inclination angles β1, β2, β3 ... so that the incident angles (for example, θ ₂ and θ ₃ ) on the inclined surface portion 162B that are reflected by the reflected light have a Brewster angle (polarization angle) or a value close thereto, Slope 162A incident on slope 162A
Since the polarized light component parallel to and the polarized light component incident on the inclined surface portion 162B and parallel to the inclined surface portion 162B can be efficiently reflected, the amount of light that can contribute to display can be efficiently increased, and the brightness of the reflective display can be increased. Can be improved. The inclination angles α, β1, β2, β3, ... Of the slopes 162A, 162B are set to optimum values depending on the incident angle θ _{i of} external light and the direction of the line of sight of the user.

In the above description, only the function of reflecting light by the reflective polarization layer 162 has been described in detail, but the reflective polarization layer 162 has the transmission axis orthogonal to the reflection axis as described above, and is semi-transmissive. It can be used as a reflective film. That is, when the illumination device is provided on the outer surface side of the lower substrate 161, a transflective liquid crystal display device can be configured. In the above description, the lower reflective polarization layer 1
62, a plurality of pairs of slope portions 16 having a wedge-shaped cross section
2A and 162B, the slope angle α of the slope portion 162A located on the upper side (left side in the figure) of the display screen of each pair is constant, and the slope portion located on the lower side (right side in the figure) of the display screen of each pair. The tilt angles β1, β2, β3, ... Of 162B are changed in the clear view direction, but conversely, the tilt angle α of the slope portion 162A located on the upper side of the display screen is changed in the clear view direction. The inclination angles β1, β2, β3 ... Of the inclined surface portion 162B located below may be constant, or the inclination angles α, β1, β of both inclined surface portions 162A, 162B.
It is good also as a structure which changes both 2 and (beta) 3 ... in a clear vision direction.

From the viewpoint of ease of in-plane film design (inclination angle design), one of the inclined surfaces 162A and 162B of each pair has a constant inclination angle in the clear viewing direction. Preferably, especially on the upper side of the display screen (left side in the figure)
If the inclination angle α of the slope portion 162A located at is constant,
This is more preferable in that the polarization separation can be made constant on the surface on which the incident light first strikes. Further, each pair of slope portions 162A, 16A
In the configuration in which one or both of the inclination angles of 2B are changed in the clear viewing direction, in particular, if the inclination angle is gradually changed, the light emitted from the liquid crystal display device can efficiently go to one point in the entire area of the display screen. Moreover, the emission direction can be controlled.

Next, in the liquid crystal display device of the present invention,
The angle (tilt angle) between one of the slopes of each pair and the lower substrate is within a range of 20 degrees to 60 degrees, and the angle between the other slope and the lower substrate ( Inclination angle)
Is preferably in the range of 45 degrees or more and 80 degrees or less. More preferably, the inclination angle of one slope portion is within the range of 40 degrees or more and 55 degrees or less, and the inclination angle of the other slope portion is 5 degrees.
By setting the angle to 0 degrees or more and 60 degrees or less, when reflective display is performed on the display unit of an electronic device such as a mobile phone using the liquid crystal display device of the present invention, the line of sight of the user who uses this electronic device The amount of light can be increased and a substantially bright display can be obtained.

In addition, for example, the incident angle of external light during use is usually about 20 to 45 degrees, and when the user is placed in front of the lower part of the center of the display screen, the constituent material of the liquid crystal display device. Since the refractive index is about 1.5, if the incident angle to the liquid crystal display device is 20 to 45 degrees, the incident angle to the inclined surface portion of the reflective polarizing layer is 15 to 30 degrees. For example, there is a liquid crystal display device having a length of 100 mm in the clear viewing direction, and in order to direct the reflection direction of light having an incident angle of 30 degrees to the liquid crystal display device to the user, two pairs are formed. Of the two slopes, the slope of the slope 162A located on the upper side of the display screen is constant within the range of 54 degrees to 56 degrees, and the slope of the slope 162B located on the lower side of the display screen is 45 degrees. It is preferable to change within the range of 51 degrees or more. If the length of the liquid crystal display device is increased, the sloped portion 162
The range of the tilt angle of B becomes wide.

Next, in the liquid crystal display device of the present invention, the lower reflective polarizing layer has a transmission axis and a reflection axis orthogonal to the transmission axis, and a part of a component of incident light parallel to the reflection axis. Is a semi-transmissive reflection type reflective polarization layer that reflects
A lower polarizing layer may be provided below the lower reflective polarizing layer. According to this structure, by providing the illuminating device below the lower polarizing layer, it is possible to obtain a transflective liquid crystal display device capable of switching between a transmissive mode and a reflective mode for display. This configuration will be described in detail below with reference to FIG.

The principle of operation of the liquid crystal display device having this structure will be described below. 6A and 6B are explanatory diagrams for explaining the operation principle when the present invention is applied to a semi-transmissive liquid crystal display device. FIG. 6A is a transmissive mode, and FIG. 6B is a reflective mode light. Shows the route. In these drawings, among the constituent elements of the liquid crystal display device of the present invention, only constituent elements necessary for explanation are shown, and an upper polarizing plate 54 and a lower reflective polarizing layer 51 are provided above and below with a liquid crystal layer 53 interposed therebetween. The lower substrate 50 is disposed outside the lower reflective polarizing layer 51, and the lower polarizing layer 55 is formed on the outer surface side of the lower substrate 50. An illumination device 58 is provided on the outer side (lower surface side in the drawing) of the lower polarizing layer 55, and a reflection plate 59 is provided on the outer surface side of the illumination device 58.

In this example, the upper polarizing plate 54 has a transmission axis in the direction perpendicular to the paper surface, and the lower polarizing layer 55 has a transmission axis parallel to the paper surface. The lower reflective polarization layer 51 is a semi-transmissive reflection type reflective polarization layer, and has a transmission axis in a direction perpendicular to the paper surface and a reflection axis orthogonal to this transmission axis. Almost all polarized light parallel to the transmission axis is transmitted, but part of polarized light parallel to the reflection axis is reflected,
Part of it is transparent. That is, the lower reflective polarizing layer 51 is of a semi-transmissive reflective type even for polarized light parallel to its reflection axis. The lower reflective polarization layer 51 has the same structure as the reflective polarization layer 162 shown in FIGS. 4 and 5, and is arranged so that the transmission axis is perpendicular to the paper surface of FIG. That is, the grooves of the reflective polarizing layer 162 shown in FIGS. 4 and 5 are arranged so as to be parallel to the paper surface of FIG.

The case of displaying in the transmissive mode shown in FIG. 6A will be described below. In the liquid crystal display device of the present invention, the transmission mode display is performed using the light emitted from the illumination device 58. The light emitted from the illumination device 58 has a lower polarization layer 5 having a transmission axis parallel to the paper surface.
5 converts it into polarized light parallel to the paper surface, and then lower substrate 5
The light passes through 0 and enters the lower reflective polarization layer 51. The lower reflective polarization layer 51 has a transmission axis perpendicular to the paper surface (a reflection axis parallel to the paper surface) as described above, and a part of the light polarized by the lower polarization layer 55 is parallel to the paper surface. The reflected light 61 is reflected and returned to the lighting device 58 side, and a part of it is transmitted and becomes transmitted light 60 that enters the liquid crystal layer 53.

Next, when the transmitted light 60 incident on the liquid crystal layer 53 is in a state where a voltage is applied to the liquid crystal layer 53 (ON state), the transmitted light 60 is hardly affected by the liquid crystal layer 53 and is transmitted to the upper polarizing plate 54. After reaching, it is absorbed by the upper polarizing plate 54 having a transmission axis perpendicular to the plane of the drawing, and the pixel is displayed dark. on the other hand,
When no voltage is applied to the liquid crystal layer 53 (off state), the transmitted light 60 incident on the liquid crystal layer 53 is converted into polarized light perpendicular to the paper surface by the optical rotation of the liquid crystal layer 53,
It reaches the upper polarizing plate 54. This light, which is polarized light parallel to the transmission axis of the upper polarizing plate 54, is transmitted through the upper polarizing plate 54 and the pixels are displayed brightly.

Here, paying attention to the reflected light 61 reflected on the back surface side (lower substrate 50 side) of the lower reflective polarization layer 51, this reflected light 61 passes through the lower substrate 50 and the lower polarization layer 55 and is illuminated. The light returns to the device 58, is reflected by the reflection plate 59 provided on the outer surface side of the illumination device 58, and is reused as light traveling toward the lower polarization layer 55 again. Then, this light again reaches the lower reflection polarization layer 51, part of which is transmitted and enters the liquid crystal layer 53, and part of it is reflected and returned to the lighting device 58 side. The light reflected by the lower reflective polarization layer 51 in this manner is transmitted through the lower reflective polarization layer 51 while being repeatedly reflected between the lower reflective polarization layer 51 and the reflection plate 59, and is used as light contributing to display. . Therefore, in the liquid crystal display device of the present invention, of the light emitted from the illumination device 58, the light transmitted through the lower polarization layer 55 can be utilized to the maximum extent, and a bright display can be obtained.

Next, the case of displaying in the reflection mode shown in FIG. 6B will be described. As shown in FIG. 6B, light incident from above the upper polarizing plate 54 is first converted into polarized light perpendicular to the paper surface by the upper polarizing plate 54 having a transmission axis perpendicular to the paper surface, and then converted into a liquid crystal layer 53. Incident. Next, when the liquid crystal is in the ON state, the incident light reaches the lower reflective polarization layer 51 with almost no effect of the liquid crystal layer 53.
Since the lower reflective polarization layer 51 has a transmission axis perpendicular to the paper surface and a reflection axis parallel to the paper surface, the light reaching the lower reflective polarization layer 51 is transmitted through the lower reflective polarization layer 51. After that, the light is transmitted through the lower substrate 50 and absorbed by the lower polarizing layer 55 having a transmission axis parallel to the paper surface, so that pixels are displayed dark.

On the other hand, when the liquid crystal layer 53 is in the off state, the light incident on the liquid crystal layer 53 is converted into polarized light parallel to the paper surface by the optical rotation effect of the liquid crystal layer 53 and reaches the lower reflection polarizing layer 51. Then, a part of the light is reflected by the lower reflection polarization layer 51 having a reflection axis parallel to the paper surface to be reflected light 63,
Part of the light is transmitted to be transmitted light 62. Liquid crystal layer 53 again
The reflected light 63 incident on is converted into polarized light perpendicular to the paper surface again by the optical rotation effect of the liquid crystal layer 53 and transmitted through the upper polarizing plate 54, and the pixel is displayed brightly. In addition, the lower reflective polarization layer 51
The transmitted light 62 that has transmitted through the lower substrate 50 and the lower polarizing layer 55.
And is emitted to the illumination device 58. Since the illumination device 58 is provided with the reflection plate 59, a part of the transmitted light 62 is reflected by the reflection plate 59 and returns to the lower substrate 50 side.
When this light enters the liquid layer 53, the brightly displayed pixels become brighter, so that the light transmitted through the lower reflective polarization layer 51 does not adversely affect the display.

Further, as shown in FIG. 6, in the liquid crystal display device of the present invention, the liquid crystal layer 53 is turned off in both the transmissive mode and the reflective mode in the bright display, and is turned on in the dark display. It is in a state. In this way, the voltage applied state of the liquid crystal to the bright and dark display is the same in the transmissive mode and the reflective mode, so that it is possible to prevent the deterioration of the contrast due to the incidence of external light during the transmissive mode display and obtain a display with excellent visibility. You can This is due to the following reasons. If the voltage application state of the liquid crystal for the bright and dark display is different between the two modes, the voltage application state of the liquid crystal of the dark display pixel in the transmissive mode is the same as the voltage application state of the bright display pixel in the reflective mode. . Therefore, when external light enters the liquid crystal display device during operation in the transmissive mode, in the dark display pixels, the light reflected by the lower reflective polarization layer 51 is emitted to the outside, and the originally dark displayed pixels are displayed brightly. It This reduces the contrast of the liquid crystal display device.

The lower reflective polarizing layer 16 shown in FIGS.
In the same manner as in 2, by changing the inclination angle of the slanted surface portion of the plurality of pairs of slanted surface portions constituting the lower reflection polarizing layer 51 on the one end side in the clear viewing direction in the clear viewing direction (the direction perpendicular to the paper in the figure). The incident direction of external light and the outgoing direction of reflected light can be matched with the direction of the line of sight of the user, and the brightness of the display can be substantially improved. The order of stacking the lower polarizing layer 55 and the lower substrate 50 may be the reverse of that shown in FIG.

Next, in the liquid crystal display device of the present invention, the lower reflective polarizing layer is partially provided on the inner surface side of the lower substrate,
A lower polarizing layer may be provided below the lower reflective polarizing layer. Even with such a configuration, a transflective liquid crystal display device can be realized. The operation of the liquid crystal display device in this case will be described below with reference to FIG.

FIG. 7 is an explanatory diagram for explaining the operation principle of the transflective liquid crystal display device according to the present invention. The liquid crystal display device shown in this figure has upper and lower polarizing plates above and below a liquid crystal layer 53. 54 and the lower reflective polarization layer 51, the lower reflective polarization layer 51
The lower polarizing layer 55 and the lower substrate 50 are disposed on the lower side of the lower substrate 50, and the illuminating device 58 and the reflecting plate 59 are provided on the outer surface side of the lower substrate 50. And, in the liquid crystal display device of this configuration,
The lower reflection polarization layer 51 is provided with an opening 57 for transmitting the light emitted from the illumination device 58, and otherwise has the same configuration as that shown in FIGS. Incidentally, FIG.
6 are the same as those in FIG. 6, and the detailed description thereof will be omitted. The transmission characteristics of the lower reflective polarization layer 51 with respect to light incident from a certain direction are characteristics in which almost all polarized light parallel to the transmission axis is transmitted and almost all polarized light parallel to the reflection axis is reflected. FIG. 7 shows a state in which the component parallel to the reflection axis of the lower reflective polarization layer 51 is totally reflected.

In the liquid crystal display device shown in FIG. 7, when displaying in the transmissive mode, as shown in FIG.
The light emitted from the illuminating device 58, after passing through the lower substrate 50, is converted into polarized light parallel to the paper surface by the lower polarizing layer 55,
Then, a part of the light passes through the opening 57, enters the liquid crystal layer 53, and is used for display. Liquid crystal layer 5
When the liquid crystal layer 53 is in the ON state, the light incident on the light beam 3 reaches the upper polarizing plate 54 with almost no effect of the liquid crystal layer 53, and is absorbed by the upper polarizing plate 54 having a transmission axis perpendicular to the plane of the drawing. , The pixels are darkly displayed. On the other hand, when the liquid crystal layer 53 is in the off state, the polarized light parallel to the paper surface is converted to the polarized light perpendicular to the paper surface by the optical rotation of the liquid crystal, and the pixel is displayed brightly through the upper polarizing plate 54. There is.

In addition, the opening 57 of the lower reflective polarization layer 51.
The light reflected on the lower surface side of the lower reflection polarization layer 51 is returned to the lighting device 58 side, is reflected by the reflection plate 59 on the outer surface side of the lighting device 58, and enters the lower reflection polarization layer 51 again. Become light. While reflection is repeated between the lower reflective polarization layer 51 and the reflection plate 59 in this manner, the light is incident on the opening 57 and is used for display. Therefore, according to this configuration, a bright display can be obtained especially in the transmission mode, and a liquid crystal display device having excellent visibility can be provided.

When displaying in the reflection mode in the liquid crystal display device shown in FIG. 7, external light incident from above the upper polarizing plate 54 is reflected by the upper polarizing plate 54 on the paper surface as shown in FIG. 7B. It is converted into polarized light which is perpendicular to, and enters the liquid crystal layer 53. Here, when the liquid crystal layer 53 is in the ON state, the incident light reaches the lower reflection polarization layer 51 with almost no effect of the liquid crystal layer 53, and the incident light is transmitted through the lower reflection polarization layer 51 having a transmission axis perpendicular to the paper surface. The light is transmitted and reaches the lower polarizing layer 55. Then, it is absorbed by the lower polarizing layer 55 having a transmission axis parallel to the paper surface. In this way, the pixels are darkly displayed. On the other hand, when the liquid crystal layer 53 is in the off state, incident light is incident on the liquid crystal layer 53.
Is converted into polarized light parallel to the paper surface by the optical rotation effect of ## EQU1 ## to reach the lower reflective polarization layer 51, and is reflected by the lower reflective polarization layer 51 having a transmission axis (reflection axis parallel to the paper surface) perpendicular to this paper surface to be reflected by the liquid crystal layer. The light is directed toward the 53 side, converted again into polarized light perpendicular to the paper surface by the optical rotation effect of the liquid crystal layer 53, transmitted through the upper polarizing plate 54 having a transmission axis perpendicular to the paper surface, and emitted upward. In this way, the pixels are displayed brightly.

The lower reflective polarizing layer 16 shown in FIGS.
In the lower reflective polarizing layer 51, as in the case of 2, the inclination angle of the slope portion of the two slope portions forming a wedge-shaped cross section on the side of one end in the clear view direction is the clear view direction (direction perpendicular to the paper surface in the figure). ), The direction of incidence of external light and the direction of emission of reflected light can be matched with the direction of the user's line of sight, and the brightness of the actual display can be improved. In addition,
The order of stacking the lower polarizing layer 55 and the lower substrate 50 may be the reverse of the configuration shown in FIG. 7.

Next, in the liquid crystal display device of the present invention,
The angle formed by the transmission axis of the lower reflective polarizing layer and the transmission axis of the lower polarizing layer is preferably in the range of 60 degrees or more and 120 degrees or less. Within the above range, it can be practically used. If the angle at which they intersect exceeds the above range,
It is not preferable because the contrast is lowered in the reflection mode.

In particular, it is preferable that the transmission axis of the lower reflective polarizing layer and the transmission axis of the lower polarizing layer are arranged substantially orthogonal to each other. In the liquid crystal display device shown in FIGS. 6 and 7, when the display in the reflection mode is performed, the light transmitted through the lower reflective polarization layer 51 is absorbed by the lower polarization layer 55 and the pixel is darkly displayed. When the transmission axis of the reflective polarizing layer 51 and the transmission axis of the lower polarizing layer 55 are orthogonal to each other, almost all the light transmitted through the lower reflective polarizing layer 51 is absorbed by the lower polarizing layer 55, which makes dark display darker. Therefore, the contrast of the reflection mode can be improved and a clear display can be obtained.

Next, the liquid crystal display device of the present invention preferably has a structure in which a scattering layer for scattering the light reflected by the lower reflective polarizing layer is provided above the lower reflective polarizing layer. . With such a configuration, it is possible to prevent the intensity of the light reflected by the lower reflective polarizing layer from becoming locally strong, thereby preventing the visibility of the display in the reflective mode from decreasing. This scattering layer may be provided at least above the lower reflective polarizing layer, and may be configured by providing a front scattering plate as a scattering layer on the outside of the upper substrate, or formed on the inner surface side of the upper and lower substrates. You may.

Next, the liquid crystal display device of the present invention may have a structure in which a color filter is provided on the inner surface side of the upper substrate or the lower substrate. With this configuration,
A reflective or transflective color liquid crystal display device can be obtained. This color filter can be formed on the inner surface side of the upper substrate, but is preferably formed directly on the lower reflective polarizing layer. By disposing a color filter directly above the lower reflective polarizing layer, it is possible to suppress color misregistration and parallax and obtain a clearer color display.

Next, an electronic apparatus of the present invention is characterized by including any one of the above liquid crystal display devices. According to this configuration, it is possible to realize an electronic device including an excellent display unit that can obtain a substantially bright display in the reflection mode and that has good brightness uniformity in the display screen. FIG. 8 is an explanatory diagram for explaining the operation of the electronic device according to the present invention. Here, the operation of the mobile phone will be described as an example of the electronic device. A mobile phone 70 shown in FIG. 8 is configured by including a display unit 72 and an operation unit 73 in a housing 71, and the display unit 72 is configured by the liquid crystal display device of the present invention. Further, the liquid crystal display device is arranged so that the clear viewing direction (X direction in the drawing) matches the vertical direction of the display unit 72. With this mobile phone 70,
Incident light entering from diagonally above the display unit 72 is reflected in the direction of the user U on the front side below the center of the display unit 72 in the entire display unit, and is bright in the direction of the user. As a result, it is possible to obtain a display with little variation in brightness within the display unit.

[0046]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) FIG. 1 shows a first embodiment of the present invention.
FIG. 3 is a partial cross-sectional view of the reflective liquid crystal display device which is the embodiment of In addition, in the following drawings, in order to make the drawings easy to see, the film thicknesses and the dimensional ratios of the respective components are appropriately changed.

As shown in FIG. 1, the liquid crystal display device 1 of the present embodiment has an STN (Super Twiste) in a space between a lower substrate 2 and an upper substrate 3 which are arranged so as to face each other.
The liquid crystal layer 4 made of d. On the inner surface side of the lower substrate 2 made of glass or resin, a lower reflective polarizing layer 6 having the same structure as the lower reflective polarizing layer 162 shown in FIGS. 4 and 5 is formed, and ITO is formed on the lower reflective polarizing layer 6. A stripe-shaped scanning electrode 8 made of a transparent conductive film such as that extends in the lateral direction in the drawing, and an alignment film 9 made of polyimide or the like is laminated so as to cover the scanning electrode 8. Further, a light absorbing layer 20 made of a light absorbing material is provided on the outer surface side of the lower substrate 2.

The lower reflective polarizing layer 6 is made of, for example, Ta ₂ O.
₅ and SiO ₂ can be formed by stacking at a stacking pitch of about 0.1 μm. Further, the material forming the lower reflective polarizing layer 6 is not limited to the above, Si, TiO ₂ or the like can be used, and the stacking pitch thereof can be appropriately changed according to the constituent material.

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

The liquid crystal display device of the present embodiment having the above-mentioned basic structure is formed by forming the lower reflective polarization layer 6 inside the lower substrate 2 having a flat surface.
Has a shape in which a plurality of pairs of slopes having a wedge-shaped cross section are continuously formed in the clear direction. The lower reflective polarization layer 6 has a constant height of 1.75 μm from the lower substrate 2 to the apex of the inclined surface portion in the clear viewing direction. Further, the inclination angle of the slope portion on the one end side (right side in the figure) in the clear view direction is from 45 degrees to 51 degrees from one end to the other end in the clear view direction (from the right side to the left side in the figure). It gradually increases, and the slope portion 162A on the other end side (the left side in the drawing) in the clear view direction.
The inclination angle of is constant at 55 degrees. The groove pitch P is 2.
It continuously changes in the range of 9 μm to 3.2 μm.

Therefore, according to the reflective liquid crystal display device of the present embodiment, the outgoing direction of the reflected light with respect to the incident light can be designed to be an arbitrary direction, and in the entire area of the display screen, the viewing direction of the user can be set. It is possible to match the emission directions of the reflected light. Therefore, it is possible to obtain a display that is substantially bright and has little variation in brightness on the display screen. Further, the light absorption layer 20 provided on the outer surface side of the lower substrate 2 absorbs the light transmitted through the lower reflective polarization layer 6 and does not return to the liquid crystal 4 side, so that the dark display can be made darker. , Which enables reflective display with excellent contrast.

(Second Embodiment) FIG. 2 shows a second embodiment of the present invention.
FIG. 3 is a partial cross-sectional view of a transflective liquid crystal display device that is an embodiment of the present invention. The liquid crystal display device shown in FIG. 2 is different from the reflection type liquid crystal display device shown in FIG. 1 in that the lower polarizing plate (lower polarizing plate) is formed on the outer surface side of the lower substrate 2 having the lower reflective deflection layer 6 formed on the inner surface. (Layer) 21 and a reflective polarizing plate 22 are laminated in this order, and a backlight (illuminating device) 5 is provided outside the reflective polarizing plate 22 and a reflective surface disposed on the outer surface side of the backlight 5. The plate 18 is provided, and other configurations are common to the liquid crystal display device shown in FIG. Therefore, of the constituent elements shown in FIG. 2, those common to FIG. 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

The liquid crystal display device of the present embodiment is a semi-transmissive reflection type liquid crystal display device which can be used while switching between a reflection mode utilizing external light and a transmission mode using the backlight 5 as a light source. However, the operating principle thereof is almost the same as that of the liquid crystal display device shown in FIG. Then, in the reflective display using external light, as in the liquid crystal display device of the first embodiment, one side of the lower reflective polarizing layer 6 having a wedge-shaped cross section, which is closer to the one end portion in the clear viewing direction, of the pair of inclined surface portions. (X in the figure
By changing the inclination angle of the slope portion (on the right side of the direction) in the clear viewing direction, it is possible to set the emission direction of the reflected light with respect to the incident light to be an appropriate direction in the entire area of the display screen. The amount of reflected light in the line-of-sight direction is efficiently increased, and a display that is substantially bright and has little variation in brightness is possible.

The reflective polarizing plate 22 may be provided without this, but by providing the reflective polarizing plate 22 between the lower polarizing plate 21 and the backlight 5, the backlight 5 serves as a light source. In the transparent mode used,
The light reflected on the lower surface side of the reflective polarizing layer 22 can be reused, the utilization efficiency of the light source can be improved, and a bright display can be realized. That is, the reflective polarizing plate 22 provided on the outer surface side of the lower polarizing plate 21 is arranged such that the transmission axis thereof is substantially parallel to the transmission axis of the lower polarizing plate 21, whereby the light is emitted from the backlight 5. The converted light is converted into polarized light parallel to the transmission axis of the reflective polarizing plate 22, and almost all of the light is transmitted through the lower polarizing plate 21. The light reflected by the reflective polarizing plate 22 is repeatedly reflected between the reflective plate 18 and the reflective polarizing plate 22 of the backlight 5, and the polarization state thereof is changed so that the light can be transmitted through the reflective polarizing plate 22. This light can also be used as light that contributes to display.

Further, in the transflective liquid crystal display device of this embodiment, the bright and dark display and the voltage application state of the liquid crystal are the same in the transmissive mode and the reflective mode. Does not lower the contrast of the liquid crystal display device. As described above, the liquid crystal display device of the present embodiment has excellent visibility in both the transmissive mode and the reflective mode.

(Third Embodiment) FIG. 3 shows the third embodiment of the present invention.
FIG. 3 is a partial cross-sectional view of a transflective liquid crystal display device that is an embodiment of the present invention. The liquid crystal display device shown in FIG. 3 is different from the transflective liquid crystal display device shown in FIG. 2 in that the lower reflective polarizing layer 6 has an opening 10 for transmitting light emitted from the backlight 5. Only the points are provided, and other configurations are common to the liquid crystal display device shown in FIG. Therefore, of the components shown in FIG. 3, those common to those in FIG. 2 are designated by the same reference numerals, and detailed description thereof will be omitted.

The operation principle of the liquid crystal display device of this embodiment shown in FIG. 3 is almost the same as that of the liquid crystal display device shown in FIG.
Then, similarly to the liquid crystal display device of the second embodiment,
In the reflective mode, by adjusting the outgoing direction of the reflected light in the entire area of the display screen to the user's line-of-sight direction, the brightness of the display visually recognized by the user is efficiently improved, and in the transmissive mode, Bright display can be realized by improving the light utilization efficiency of the backlight 5.

(Electronic Device) An example of an electronic device equipped with the liquid crystal display device of each of the above embodiments will be described.

FIG. 9A is a perspective view showing an example of a mobile phone. In this figure, reference numeral 1000 indicates a mobile phone main body, and reference numeral 1001 indicates a liquid crystal display unit using the above liquid crystal display device.

FIG. 9B is a perspective view showing an example of a wrist watch type electronic device. In this figure, reference numeral 1100 indicates a watch body, and reference numeral 1101 indicates a liquid crystal display unit using the above liquid crystal display device.

FIG. 9C is a perspective view showing an example of a portable information processing device such as a word processor and a personal computer. Figure 9
In (c), reference numeral 1200 is an information processing device, reference numeral 1
Reference numeral 202 denotes an input unit such as a keyboard, reference numeral 1204 denotes an information processing apparatus main body, and reference numeral 1206 denotes a liquid crystal display unit using the above liquid crystal display device.

The above-described electronic devices shown in FIGS. 9A to 9C are provided with the liquid crystal display section using the liquid crystal display device according to the above-mentioned embodiment, so that the user's line of sight can be seen in the entire area of the display screen. The amount of light reflected in the direction can be increased, and the brightness of the display in the reflection mode can be efficiently improved and the in-plane uniformity can be improved.

[0064]

As described above in detail, in the liquid crystal display device of the present invention, the liquid crystal layer is sandwiched between the upper substrate and the lower substrate facing each other, and the upper polarizing layer is provided above and below the liquid crystal. And a lower reflective polarizing layer, wherein the lower reflective polarizing layer is formed by laminating prismatic dielectric interference films in which a plurality of pairs of slanted surfaces having a wedge-shaped cross section are continuously formed, and the pair is formed. Of the two inclined surfaces, the inclination angle of the inclined surface on the one end side in the clear view direction is changed in the clear view direction, so that the incident direction of external light and the reflected light By making the emitting direction different, the emitting direction of the reflected light can be matched with the direction of the line of sight of the user in the entire area of the display screen. Therefore, according to the size of the display screen and the position of the user's viewpoint, the inclination angle of the slope portion on the one end side in the clear vision direction is set for each slope portion, so that It is possible to increase the amount of light in the line-of-sight direction with good in-plane uniformity,
The display brightness in the reflection mode can be efficiently improved.

Further, according to the electronic apparatus of the present invention, since the liquid crystal display unit using the liquid crystal display device of the above embodiment is provided, the amount of reflected light in the direction of the line of sight of the user is increased in the entire area of the display screen. However, the brightness of the display in the reflection mode can be efficiently improved and the in-plane uniformity can be improved.

[Brief description of drawings]

FIG. 1 is a diagram showing a partial cross-sectional structure of a reflective liquid crystal display device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a partial cross-sectional structure of a transflective liquid crystal display device according to a second embodiment of the present invention.

FIG. 3 is a diagram showing a partial cross-sectional structure of a transflective liquid crystal display device according to a third embodiment of the present invention.

FIG. 4 is an explanatory diagram for explaining the operation principle of the liquid crystal display device according to the present invention.

5 is a perspective view showing the structure of the lower reflective polarizing layer shown in FIG. 4. FIG.

6A and 6B are explanatory diagrams for explaining the operation principle of the liquid crystal display device according to the present invention, FIG. 6A shows a transmission mode, and FIG. 6B shows a reflection mode.

7A and 7B are explanatory views for explaining the operation principle of the liquid crystal display device according to the present invention, FIG. 7A shows a transmission mode, and FIG. 7B shows a reflection mode.

FIG. 8 is an explanatory diagram for explaining the operation of the electronic device according to the invention.

9A to 9C are perspective views showing an example of an electronic device of the present invention.

FIG. 10 is a partial cross-sectional view showing an example of the previously proposed liquid crystal display device.

FIG. 11 is an explanatory diagram for explaining the operation principle of the liquid crystal display device proposed previously.

FIG. 12 is a partial cross-sectional view showing an example of a conventional liquid crystal display device.

FIG. 13 is an explanatory diagram showing an optical path in the vicinity of the lower reflective polarizing layer shown in FIG.

[Explanation of symbols]

1,160 Liquid crystal display device 2,161 Lower substrate 3,163 Upper substrate 4 Liquid crystal layer 5 Backlight (illumination device) 6,162 Bottom reflective polarizing layer 11 color filters 13 Upper polarizing plate (upper polarizing layer) 16 Forward scattering plate (scattering layer) 21 Lower polarizing plate (lower polarizing layer) 22 Reflective polarizing plate

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 2H049 BA02 BA43 BB03 BB62 BB63                       BC22                 2H091 FA08 FA14Z FA21Z FB13                       FC01 FD04 FD07 GA01 LA03                       LA11 LA12 LA13 LA18                 5C094 AA12 BA43 ED01 ED03 ED14                       FA04 JA09

Claims (11)

[Claims] 1. A liquid crystal display device in which a liquid crystal layer is sandwiched between an upper substrate and a lower substrate facing each other, the liquid crystal display device comprising an upper polarizing layer and a lower reflective polarizing layer above and below the liquid crystal layer. The lower reflective polarization layer is formed by laminating prism-shaped dielectric interference films in which a plurality of pairs of slanted surface portions having a wedge-shaped cross section are continuously formed, and among the two slanted surface portions forming the pair. A liquid crystal display device, wherein an inclination angle of a slope portion on one end side in the clear viewing direction is changed in the clear viewing direction. 2. The inclination angle of one of the two slopes forming the pair on the one end side in the clear view direction is gradually changed in the clear view direction. Item 3. The liquid crystal display device according to item 1. 3. The inclination angle of the slope portion on the other end side in the clear view direction of the two slope portions forming the pair is constant. The liquid crystal display device according to item 1. 4. Of the two slopes forming the pair, one slope has an inclination angle of 20 degrees or more and 60 degrees or less, and the other slope has an inclination angle of 45 degrees or more and 80 degrees or less. The liquid crystal display device according to claim 1, wherein the liquid crystal display device is provided. 5. The lower reflective polarizing layer has a transmission axis and a reflection axis orthogonal to the transmission axis, reflects a part of a component of incident light parallel to the reflection axis, and transmits a part of the component. 5. The liquid crystal display device according to claim 1, wherein the liquid crystal display device is a transflective reflective polarizing layer, and a lower polarizing layer is provided below the lower reflective polarizing layer. 6. The lower reflective polarizing layer is partially provided on the inner surface side of the lower substrate, and the lower polarizing layer is provided below the lower reflective polarizing layer. Through 5
The liquid crystal display device according to any one of 1. 7. The angle between the transmission axis of the lower reflective polarizing layer and the transmission axis of the lower polarizing layer is 60 degrees or more and 120 degrees or less, according to claim 5 or 6. The liquid crystal display device according to item. 8. The liquid crystal display device according to claim 7, wherein a transmission axis of the lower reflective polarizing layer and a transmission axis of the lower polarizing layer are arranged substantially orthogonal to each other. 9. The scattering layer for scattering the light reflected by the lower reflective polarizing layer is provided above the lower reflective polarizing layer. The liquid crystal display device according to item 1. 10. The inner surface of the upper substrate or the lower substrate,
The liquid crystal display device according to claim 1, further comprising a color filter. 11. An electronic apparatus comprising the liquid crystal display device according to claim 1. Description: