JPH11212083A - Liquid crystal device and electronic equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the reflection or semi-transmissible reflection liquid crystal device with more lightness and higher contrast by arranging the reflection axis of a reflection polarizer almost parallel to the longitudinal direction of a display screen of the liquid crystal device. SOLUTION: This liquid crystal device is provided with a liquid crystal panel holding liquid crystal between a pair of substrates and a polarizing board arranged on one side of the liquid crystal panel. Besides, this device is provided with the reflection polarizer arranged on the opposite side of the polarizing board to the liquid crystal panel and constituted by alternately laminating many first layers 101 having refraction factor anisotropy in a plane and second layers 102 having no refraction factor anisotropy in the plane and a light absorbing layer arranged on the opposite side of the liquid crystal panel to the reflection polarizer. Then, a reflection axis 103 of the reflection polarizer is arranged almost parallel to the longitudinal direction of the display screen of the liquid crystal device. Thus, by devising the arrangement of the reflection axis while utilizing the reflection polarizer, lightness and contrast ratio can be more improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal device, and more particularly, to a reflection type and a transflective type liquid crystal device, and further to an electronic apparatus equipped with the liquid crystal device.

[0002]

2. Description of the Related Art Reflective liquid crystal devices and transflective liquid crystal devices with low power consumption are suitable for use in information tools such as PDAs and portable electronic devices such as mobile phones and watches. However, conventional reflective liquid crystal devices and transflective liquid crystal devices have a problem that the display is dark.

[0003] As one means for solving such a problem,
A method using a reflective polarizer comprising a birefringent dielectric multilayer film is disclosed in Japanese Patent Application Laid-Open No. 9-506985, International Publication WO97 / 01788, Conference Recor.
d of the 1997 International Display Research Confe
rence, M-98, 1997 and the like.

The birefringent dielectric multilayer film has a function of reflecting a predetermined linearly polarized light component and transmitting other polarized light components. When such a reflective polarizer is used in a reflective liquid crystal device or a semi-transmissive reflective liquid crystal device, unlike a metal reflector that has been widely used in the past, it totally reflects light of a predetermined polarization component and absorbs light of an absorption type. Since it does not absorb light like a plate, it has a feature that a very bright display can be obtained.

[0005]

However, when such a conventional reflective polarizer using a birefringent dielectric multilayer film is used, there is a problem that the display contrast is reduced. The reason that such a problem occurs is that the degree of polarization of the reflective polarizer with respect to light incident obliquely is low.

Accordingly, an object of the present invention is to provide a reflective or transflective liquid crystal device which is bright and has high contrast by devising the arrangement of the reflective axes of the reflective polarizer.

[0007]

A liquid crystal device according to the present invention comprises: a liquid crystal panel having liquid crystal sandwiched between a pair of substrates; a polarizing plate disposed on one side of the liquid crystal panel; The polarizing plate is disposed on the opposite side, a first layer having an in-plane refractive index anisotropy and a second layer having no in-plane refractive index anisotropy are alternately laminated in large numbers. A liquid crystal device comprising a configured reflective polarizer and a light absorbing layer disposed on a side opposite to the liquid crystal panel with respect to the reflective polarizer, wherein a vertical direction of a display screen in the liquid crystal device, It is characterized in that the reflection axis of the reflection polarizer is arranged substantially in parallel.

A liquid crystal panel having liquid crystal interposed between a pair of substrates; a polarizing plate disposed on one side of the liquid crystal panel; and a polarizing plate disposed on a side of the liquid crystal panel opposite to the polarizing plate. The reflective polarizer, which is formed by alternately stacking a large number of first layers having in-plane refractive index anisotropy and second layers having no in-plane refractive index anisotropy, A lighting device disposed on a side opposite to the liquid crystal panel with respect to the liquid crystal device, wherein a vertical direction of a display screen of the liquid crystal device and a reflection axis of the reflective polarizer are substantially parallel to each other. It is characterized by having been done.

Here, the polarizing plate has a function of absorbing a predetermined linearly polarized light component and transmitting the remaining polarized light component, and the reflective polarizer has a function of reflecting the predetermined linearly polarized light component and transmitting the remaining polarized light component. .

It is to be noted that the term "substantially parallel" means that the vertical direction is approximately ± 3
It refers to a range of 0 degrees, but more preferably refers to a range of ± 15 degrees. Outside of this range, high contrast cannot be obtained under a normal lighting environment. This is because, in general, a reflective polarizer exhibits a high degree of polarization with respect to light oscillating in a plane including its reflection axis.

Also, of the three main refractive indices nx, ny, and nz of the first and second layers of the reflective polarizer, a direction perpendicular to the stretching direction in the plane with the refractive index nz in the film thickness direction. Refractive index n
The ratio of y is different between the two layers.

Although nx and ny exist in the in-plane principal refractive index, since this reflective polarizer is formed by stretching, the refractive index in the direction parallel to the principal stretching direction is represented by n.
x, the refractive index in the direction perpendicular to x is distinguished from ny.
Many substances are optically positive and therefore nx> ny, but optically negative substances such as polystyrene have nx <ny.
ny. Claim 2 indicates that nz / ny of the first layer is different from nz / ny of the second layer. With such a configuration, the reflection polarizer according to claim 2 has a poor polarization degree with respect to light obliquely incident particularly on the yz plane.
A high degree of polarization is maintained for light incident obliquely in the -z plane (that is, a plane including the reflection axis). This effect can be explained by matching the refractive indices of the two layers with respect to light incident obliquely.

[0013] Also, the electronic apparatus of the present invention is a liquid crystal panel having a liquid crystal sandwiched between a pair of substrates, a polarizing plate disposed on one side of the liquid crystal panel, and a polarizing plate with respect to the liquid crystal panel. A reflection layer which is disposed on the opposite side to the first layer having an in-plane refractive index anisotropy and the second layer having no in-plane refractive index anisotropy is alternately stacked. A polarizer,
An electronic apparatus including, as a display unit, a liquid crystal device including a light absorbing layer disposed on a side opposite to the liquid crystal panel with respect to the reflective polarizer, wherein a vertical direction of a display screen in the liquid crystal device, The reflection axis of the polarizer is arranged substantially in parallel.

A liquid crystal panel having liquid crystal sandwiched between a pair of substrates; a polarizing plate disposed on one side of the liquid crystal panel; and a polarizing plate disposed on a side of the liquid crystal panel opposite to the polarizing plate. The reflective polarizer, which is formed by alternately stacking a large number of first layers having in-plane refractive index anisotropy and second layers having no in-plane refractive index anisotropy, An electronic apparatus comprising, as a display unit, a liquid crystal device including a lighting device disposed on a side opposite to the liquid crystal panel with respect to the liquid crystal panel, wherein a vertical direction of a display screen of the liquid crystal device and a reflection polarizer are provided. It is characterized in that the reflection axis and the reflection axis are arranged substantially in parallel.

[0015] With this configuration, the electronic apparatus of the present invention can obtain high-quality display with low power consumption.

[0016]

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

(Embodiment 1) FIG. 1 is a view showing a main part of the structure of a reflective polarizer used in a liquid crystal device according to the first or second aspect of the present invention. The reflective polarizer is basically a birefringent dielectric multilayer film, and is formed by alternately stacking two types of polymer layers 101 and 102. The two types of polymers are selected from a material with a high photoelastic modulus and a material with a low photoelastic modulus, while taking care that the refractive indices of the ordinary rays of both are approximately equal. .
For example, PEN (2,6-
Polyethylene naphthalate) as a small material
Select oPEN (70-naphthalate / 30-terephthalate copolyester). When both films are alternately laminated and stretched about 5 times in the x-axis direction of the orthogonal coordinate system 103 in FIG. 1, the refractive index in the x-axis direction is about 1.
88, about 1.64 for the coPEN layer. The refractive index in the y-axis direction was about 1.64 in both the PEN layer and the coPEN layer. When light is incident on the laminated film from the normal direction, the light component vibrating in the y-axis direction passes through the film as it is. This is the transmission axis. On the other hand, the component of light that vibrates in the x-axis direction is that the PEN layer and the coPEN layer
Reflection occurs only when certain conditions are satisfied. This is the reflection axis. The condition is that the sum of the optical path length of the PEN layer (the product of the refractive index and the film thickness) and the optical path length of the coPEN layer (the product of the refractive index and the film thickness) is equal to one half of the light wavelength. is there. If such PEN layers and coPEN layers are laminated in several tens or more layers, preferably in more than one hundred layers, and in a thickness of about 30 μm, almost all of the components of light vibrating in the x-axis direction can be reflected.

The ideal reflection polarizer produced in this way produces a polarization ability only with light of a single designed wavelength. Of course, in practice, the thicknesses of the PEN layer and the coPEN layer vary, so that the polarization ability is generated with a certain wavelength width, but the width is still several tens of nm. Therefore, in order to provide a polarizing capability over a wide wavelength range of visible light, a plurality of reflective polarizers having different polarization reflection wavelength ranges are stacked with their axes aligned. The reflective polarizer thus configured is
It exhibited a high degree of polarization of 90% or more over almost the entire visible light range.

The above is a description of the behavior of light incident on the reflective polarizer from the normal direction. The main feature of the present invention lies in the behavior of light entering obliquely. FIG. 2 is a diagram showing the refractive index characteristics of two types of layers 101 and 102 constituting the reflective polarizer of the present invention. Reference numeral 201 denotes a refractive index ellipsoid of the first layer 101 formed by stretching a material having a large photoelastic coefficient, and reference numeral 202 denotes a refractive index ellipsoid of the second layer 102 formed by stretching a material having a small photoelastic coefficient. Let the three principal indices of each ellipsoid be nx, n
y and nz. However, the refractive indices 211 and 221 in a direction parallel to the main stretching direction in the plane of the layer (xy plane 231).
Is nx, the refractive indices 212 and 222 in the direction perpendicular to the main stretching direction in the plane of the layer are ny, and the refractive indices 213 and 2 in the film thickness direction are
23 is nz. However, the main stretching direction corresponds to the x-axis direction in FIG. 1 in the above description, and indicates a direction in which the stretching ratio is larger when biaxial stretching is performed.

Now, as a result of precisely measuring the refractive index of each layer of the reflective polarizer of Example 1, as for the layer 101, nx
= 1.877, ny = 1.641, and nz = 1.533. For the layer 102, nx = 1.64
2, ny = 1.640 and nz = 1.616, which were almost isotropic. However, this measurement was performed for layers 101 and 10
2 is a value obtained by measuring a film separately prepared and stretched similarly.

As described above, the layer 101 has in-plane refractive index anisotropy (nx-ny = 0.235), and the layer 102 has in-plane refractive index anisotropy (nx-ny = 0.002). ). Moreover, the ratio nz between nz and ny in the layer 101
/Ny=0.9242 means that nz and ny in the layer 102
Is significantly smaller than the ratio nz / ny = 0.9854.

Thus, nz / ny in the first layer
And nz / ny in the second layer are configured to be significantly different from each other, so that of the light 242 incident obliquely in the yz plane, the refractive index for the light oscillating in the yz plane is There is a gap between the first layer and the second layer. Therefore, there is no effect on the light oscillating in the x-axis direction, which is the reflection axis. However, as for the light oscillating in a direction perpendicular thereto, the reflected light increases as the incident angle increases, and the degree of polarization deteriorates. On the other hand, the light 241 obliquely incident on the xz plane has the same refractive index of the first layer and the second layer with respect to light vibrating in the y-axis direction, which is the transmission axis. The degree of polarization is small.

FIG. 3 is a diagram showing the dependence of the degree of polarization on the angle of incident light. (A) is the incident light angle dependence in the xz plane, and (b) is the incident light angle dependence in the yz plane. Curves 301 and 311 are the characteristics of the reflective polarizer used in Example 1. (B) is more dependent on the incident angle than (a), and the degree of polarization is more likely to be degraded, because the polarized light that should be transmitted is reflected.

For comparison, the first layer and the second layer have nz /
The properties of the carefully stretched reflective polarizer are shown at 302 and 312 so that ny is approximately equal. The refractive index of this reflective polarizer is nx = 1.874 and ny =
1.644, nz = 1.621, n for layer 102
x = 1.642, ny = 1.640, nz = 1.616
Met. Although it is technically difficult to produce such a reflective polarizer, the incident angle dependency tends to be larger in (b) than in (a). Therefore, the effect of the present invention can be obtained even in a liquid crystal device using such a reflective polarizer.

FIG. 4 is a diagram showing a main part of the structure of a liquid crystal device according to the first or second aspect of the present invention.
First, the configuration will be described. In FIG. 4, reference numeral 401 denotes a polarizing plate;
402 is a retardation film, 403 is an upper glass substrate, 4
04 is a liquid crystal layer, 405 is a lower glass substrate, 406 is a light scatterer, 407 is a reflective polarizer, 408 is a light absorber, 409
Is a scanning electrode made of ITO, and 410 is a signal electrode made of ITO. 401 and 402, 402 and 403, 40
5 and 406, 406 and 407, and 407 and 408 are bonded to each other with glue. Although the vertical substrates are drawn widely apart, this is for the sake of clarity of the drawing. In addition to the components shown in the figure, a liquid crystal alignment film, an insulating film, spacer balls, a driver I
Although elements such as C and a drive circuit are also indispensable, they are not particularly necessary for describing the present invention, and are omitted because they may rather complicate the drawing and make it difficult to understand.

Next, each component will be described in order. The polarizing plate 401 has a function of absorbing a predetermined linearly polarized light component and transmitting other polarized light components. This is the most commonly used type of polarizing plate at present, and is produced by adsorbing a halogen substance such as iodine or a dichroic dye onto a polymer film such as polyvinyl butyral.

The retardation film 402 is, for example, a uniaxially stretched film of a polycarbonate resin, and is used for compensating the coloring of the display of the STN type liquid crystal device. T
In the case of an N-type liquid crystal device, it is often omitted.

The liquid crystal layer 404 is composed of a STN nematic liquid crystal composition twisted from 180 degrees to 270 degrees. When the display capacity is small, a TN liquid crystal composition twisted by 90 ° may be used. The twist angle is determined by the direction of the alignment treatment on the surface of the vertical glass substrate and the amount of the chiral agent added to the liquid crystal.

As the light scatterer 406, a plastic film in which transparent beads are dispersed can be used. Beads are mixed in the adhesive to substitute for the light scatterer, and 405 is directly converted to 407
May be adhered to. Alternatively, a light control plate that scatters only light incident from a specific angle may be used. Such a light control board is available from Sumitomo Chemical Co., Ltd.
It has been released as. Note that the light scattering here refers to weak scattering that does not disturb the polarization. The light scattering plate is arranged for appropriately diffusing the reflected light of the reflective polarizer close to the mirror surface.

The reflective polarizer 407 has already been described in detail.

The light absorbing plate 408 is used by adhering a black vinyl sheet or black paper or by directly applying a black paint. In addition, if it is a relatively dark color other than black, it can be used depending on preference, such as blue, brown, and gray. This light absorbing plate is arranged for the purpose of absorbing unnecessary polarized light, but when this polarized light is used in a transflective liquid crystal device or the like,
A translucent light absorbing plate or polarizing plate may be used.

Next, specific conditions of the liquid crystal panel will be introduced. First, the retardation (product of birefringence and layer thickness) of the liquid crystal layer 404 in FIG. 4 was set to 1.00 μm, and the retardation of the retardation film 402 was set to 0.65 μm. FIG. 5 is a diagram showing the relationship between the axes, 501 is the polarization axis (transmission axis) of the polarizing plate 101, 502 is the slow axis (stretching axis) of the retardation film, 503 is the rubbing axis of the upper glass substrate, 504 Is the rubbing axis of the lower glass substrate, and 505 is the reflection axis of the reflective polarizer. Reference numeral 510 indicates the vertical direction of the liquid crystal panel. Here, an angle 511 between 501 and 502 is formed.
To the right 32 degrees, and the angle 512 between 502 and 503
At 7 degrees, the angle 504 forms an angle 503 with 503, that is, the twist angle 513 of the liquid crystal is set at 240 degrees to the left, and the angle
14 was set to 46 degrees to the left. Since the two rubbing axes 503 and 504 are bilaterally symmetric, the polarization axis 50 of the reflective polarizer is
The angle 515 between the liquid crystal panel 5 and the left-right direction 510 of the liquid crystal panel is 14 degrees to the right, which can be said to be substantially parallel to the vertical direction.

The liquid crystal device thus manufactured has a feature that it is 30% or more brighter than a liquid crystal device using two ordinary polarizing plates. There are two reasons. One is that while the reflectivity of metallic aluminum is only less than 90%, the reflective polarizer of the present invention reflects almost 100% of light parallel to the reflection axis. Another reason is that ordinary absorption-type polarizers use dichroic substances such as halogen substances such as iodine and dyes, and the dichroic ratio is not necessarily high, so that about 20% of light is wasted. That is what we do.

Further, this liquid crystal device has a feature that the display contrast is high particularly when light is incident from above (12 o'clock direction). This is because the degree of polarization of the reflective polarizer 407 is high when light is incident from above. Generally, in a reflection type liquid crystal device, since an observer is located in front of the panel or in a downward direction (6 o'clock direction), light incident from above is most likely to reach the observer. Therefore, it is very preferable that the contrast with respect to light incident from above is high.

The fact that the direction of the reflection axis of the reflective polarizer is substantially parallel to the longitudinal direction of the liquid crystal panel means that an expensive reflective polarizer can be efficiently obtained from its raw material, which is advantageous in terms of cost. .

(Embodiment 2) An example of another liquid crystal device according to the first or second aspect of the present invention will be described.
FIG. 6 is a diagram showing a main part of the structure. First, the configuration will be described. 6, 601 is a polarizing plate, 602 is a counter substrate, 603 is a liquid crystal composition, 604 is an element substrate, 605 is a light scattering plate, 606 is a reflective polarizer, 607 is a light absorbing plate, 6
08 is a light guide plate of a backlight, 609 is a light reflection plate, 61
Reference numeral 0 denotes a backlight light source, on which a color filter 611 and a counter electrode (scanning line) 612 are provided on a counter substrate 602, and a signal line 613 and a pixel electrode 6 are provided on an element substrate 604.
14. An MIM element 615 was provided. Where 601 and 60
2, 604 and 605, 605 and 606, 606 and 607
Are drawn apart from each other for the sake of clarity of the figure, and are actually glued together. Further, the space between the opposing substrate 602 and the element substrate 604 is drawn widely apart, but for the same reason, there is actually only a gap of about several μm to about several tens μm. FIG. 6 shows a part of the liquid crystal device, so that a 3 × 3 matrix formed by three scanning lines 612 and three signal lines 616 intersect with each other.
That is, although only nine dots are shown, actually, it has more dots.

The counter electrode 612 and the pixel electrode 614 were formed of transparent ITO. The signal line 613 was formed of metal Ta. In the MIM element, the insulating film Ta2O5 is made of metal Ta and metal C.
r. The liquid crystal composition 603 is a nematic liquid crystal twisted by 90 degrees. Reference numeral 611 denotes red (indicated by "R" in the figure) and green ("G" in the figure) which are three primary colors of additive color mixture.
) And blue (indicated by “B” in the figure) and arranged in a mosaic pattern.

Although the MIM active matrix type liquid crystal device has been described as an example here, the effect of the present invention is not changed even if a simple matrix type liquid crystal device is adopted. In such a case, connect the signal line to a rectangular IT
O is formed, and the MIM element and the pixel electrode are not provided. Also, instead of the TN mode, an STN mode similar to that of the first embodiment is employed.

As the polarizing plate 601 and the reflective polarizer 606, the same ones as in the first embodiment were used.

As the semi-light absorbing plate 607, a gray translucent film can be used. As a gray translucent film, 10% or more and 80% with respect to light in the entire wavelength range of visible light
A scattering film having a transmittance of 50% or more and 70% or less is suitable. Such a film is marketed, for example, by Tsujimoto Electric Manufacturing Co., Ltd. under the name of light diffusion film D202 (trade name). Further, a partially transparent light absorbing film, that is, a black film having a large number of fine holes having a diameter of several μm, which cannot be observed with the naked eye, can also be used. In addition, the absorption type polarizing plate is replaced with a reflective polarizer 6.
06 and the axis may be shifted.

As the light guide 608 of the backlight, a flat plate of acrylic resin having good transparency was used, and a white paint was printed on the surface thereof. A white light reflecting plate 609 is disposed on the back of the light guide to return light leaking backward to the front.

Next, specific conditions of the liquid crystal panel will be introduced. First, the retardation (the product of the birefringence and the layer thickness) of the liquid crystal layer 603 in FIG. 6 was set to 0.42 μm. FIG. 7 is a diagram showing the relationship between the respective axes.
702 is a rubbing axis of the upper glass substrate, 703 is a rubbing axis of the lower glass substrate, and 704 is a reflection axis of the reflective polarizer 606. Reference numeral 710 denotes the vertical direction (horizontal direction) of the liquid crystal panel. Here, 701 and 7
03, 702 and 704 are parallel to each other, and the angle 711 formed between them is set to 90 degrees. At this time,
The angle between the reflection axis 704 of the reflection polarizer 606 and the vertical direction 710 of the liquid crystal panel is 0 degree.

When the angle formed by the reflection axis and the vertical direction of the liquid crystal panel deviated from 0 °, how the characteristics changed was confirmed as follows. First, the light source is fixed at a tilt angle of 45 degrees from the 12 o'clock direction and the normal direction. Then, the liquid crystal panel was rotated right and left by 90 degrees around the normal line direction, and the contrast ratio was measured. That is, in FIG. 7, 710 is fixed, and 701, 702, 703,
And the contrast ratio was measured. FIG. 8 shows the result. The horizontal axis is the rotation angle of the liquid crystal panel, which is equal to the angle that the reflection axis makes with the vertical direction of the liquid crystal panel.
When this angle is 0 degree, the contrast ratio has a maximum value of 6.2.
I take the. Up to ± 15 degrees, almost the same contrast is maintained, but beyond ± 30 degrees, the contrast ratio sharply decreases. Therefore, the reflection axis of the reflective polarizer is preferably in the range of ± 30 degrees in the direction parallel to the longitudinal direction of the liquid crystal panel, and more preferably in the range of ± 15 degrees. Outside of this range, high contrast cannot be maintained under a general lighting environment. Within this range, the reflection axis direction may be determined in consideration of other various factors, for example, the clear viewing direction of the liquid crystal.

The liquid crystal device thus manufactured is 30% or more brighter than a liquid crystal device using two ordinary polarizing plates. In addition, there is a feature that display contrast is high particularly when light is incident from above (12 o'clock direction). Further, the fact that the direction of the reflection axis of the reflective polarizer is substantially parallel to the longitudinal direction of the liquid crystal panel means that an expensive reflective polarizer can be efficiently obtained from its raw material, which is advantageous in cost.

(Embodiment 3) Three examples of the electronic apparatus according to the third aspect of the present invention will be described.

The liquid crystal device of the present invention is suitable for portable equipment used in various environments and requiring low power consumption.

FIG. 9A shows a mobile phone, and a main body 901 is shown.
A display unit 902 is provided at an upper part of the front surface of the display. Mobile phones are used in all environments, both indoors and outdoors. Especially, it is often used in cars, but the inside of cars at night is very dark. Therefore, it is desirable that the display device used in the mobile phone is a transflective liquid crystal device capable of performing transmissive display using auxiliary light as needed, mainly reflective display with low power consumption. The liquid crystal device of the present invention is brighter than conventional liquid crystal devices and has a higher contrast ratio in both reflective display and transmissive display.

FIG. 9B shows a watch, which is a main body 903.
The display unit 904 is provided at the center of the display. An important aspect in watch applications is luxury. The liquid crystal device of the present invention is not only bright and has a high contrast, but also has a small coloring due to a small change in characteristics due to the wavelength of light. Therefore, a very high-quality display can be obtained as compared with the conventional liquid crystal device.

FIG. 9C shows a portable information device.
A display unit 906 is provided on the upper side of the display unit 05, and an input unit 907 is provided on the lower side. In addition, touch keys are often provided on the front of the display unit. Normal touch keys have many surface reflections,
The display is hard to see. Therefore, conventionally, a transmissive liquid crystal device has often been used even though it is portable. However, since the transmissive liquid crystal device always uses the backlight, the power consumption is large and the battery life is short. Even in such a case, the liquid crystal device of the present invention can be used for a portable information device because the display is bright and vivid both in the reflective type and the transflective type.

[0050]

As described above, according to the present invention, a reflective or transflective liquid crystal device having a bright and high contrast can be obtained by utilizing a reflective polarizer and devising the arrangement of the reflective axes. Can be provided.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a main part of a structure of a reflective polarizer used in a liquid crystal device according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating refractive index characteristics of two types of layers constituting a reflective polarizer used in the liquid crystal device according to the first embodiment of the present invention.

FIG. 3 is a diagram showing the incident angle dependence of the degree of polarization of the reflective polarizer used in the liquid crystal device according to the first embodiment of the present invention.

FIG. 4 is a diagram illustrating a main part of a structure of the liquid crystal device according to the first embodiment of the present invention.

FIG. 5 is a diagram illustrating a relationship between axes of the liquid crystal device according to the first embodiment of the present invention.

FIG. 6 is a diagram illustrating a main part of a structure of a liquid crystal device according to a second embodiment of the present invention.

FIG. 7 is a diagram illustrating a relationship between axes of a liquid crystal device according to a second embodiment of the present invention.

FIG. 8 illustrates a liquid crystal device according to a second embodiment of the present invention.
FIG. 11 is a diagram illustrating a change in contrast ratio when the liquid crystal panel is rotated with the light source fixed at a tilt angle of 45 degrees in the 12 o'clock direction.

FIG. 9 is a diagram illustrating an appearance of an electronic device according to a third embodiment of the present invention. (A) mobile phone, (b) watch,
(C) portable information devices.

[Explanation of symbols]

Reference Signs List 101 Layer stretched with material having high photoelastic modulus 102 Layer stretched with material having low photoelasticity 103 Orthogonal coordinate system, x-axis direction is stretch direction, reflection axis 201 Index ellipsoid of layer 101 202 Refraction of layer 102 Index ellipsoid 211 Refractive index nx in a direction parallel to the main stretching direction in the plane of layer 101 nx 212 Refractive index ny 213 in a direction perpendicular to the main stretching direction in the plane of layer 101 Refractive index nz in the thickness direction of layer 101 221 Refractive index nx in the direction parallel to the main stretching direction in the plane of the layer 102 222 Refractive index ny 223 in the direction perpendicular to the main stretching direction in the plane of the layer 102 Refractive index nz 231 x− in the film thickness direction of the layer 102 y plane (plane parallel to the reflective polarizer surface) 232 xz plane (plane including both the extending direction and the thickness direction of the reflective polarizer) 233 yz plane (direction perpendicular to the extending direction of the reflective polarizer) Light incident from obliquely in the optical 242 y-z plane obliquely incident film thickness direction in both comprise plane) in 241 x-z plane

Claims (5)

[Claims] A liquid crystal panel having a liquid crystal sandwiched between a pair of substrates; a polarizing plate disposed on one side of the liquid crystal panel; and a polarizing plate disposed on a side of the liquid crystal panel opposite to the polarizing plate. A reflective polarizer configured by alternately laminating a large number of first layers having in-plane refractive index anisotropy and second layers having no in-plane refractive index anisotropy; A light absorbing layer disposed on the side opposite to the liquid crystal panel with respect to the element, wherein a vertical direction of a display screen in the liquid crystal device and a reflection axis of the reflective polarizer are substantially parallel to each other. A liquid crystal device, which is disposed. 2. A liquid crystal panel in which liquid crystal is sandwiched between a pair of substrates; a polarizing plate disposed on one side of the liquid crystal panel; and a polarizing plate disposed on a side of the liquid crystal panel opposite to the polarizing plate. A reflective polarizer configured by alternately laminating a large number of first layers having in-plane refractive index anisotropy and second layers having no in-plane refractive index anisotropy; A lighting device arranged on the side opposite to the liquid crystal panel with respect to the liquid crystal panel, wherein a vertical direction of a display screen in the liquid crystal device and a reflection axis of the reflective polarizer are substantially parallel to each other. A liquid crystal device characterized by being performed. 3. The liquid crystal device according to claim 1, wherein the three main refractive indices nx, ny, and nz of the first layer and the second layer of the reflective polarizer are in a thickness direction. Wherein the ratio of the refractive index nz to the refractive index ny in the direction perpendicular to the stretching direction in the plane is different between the two layers. 4. A liquid crystal panel having liquid crystal sandwiched between a pair of substrates; a polarizing plate disposed on one side of the liquid crystal panel; and a polarizing plate disposed on a side of the liquid crystal panel opposite to the polarizing plate. A reflective polarizer configured by alternately laminating a large number of first layers having in-plane refractive index anisotropy and second layers having no in-plane refractive index anisotropy; An electronic apparatus comprising, as a display unit, a liquid crystal device including a light absorbing layer disposed on a side opposite to the liquid crystal panel with respect to a liquid crystal panel, wherein a vertical direction of a display screen in the liquid crystal device and a reflection polarizer are provided. An electronic device, wherein a reflection axis and a reflection axis are arranged substantially in parallel. 5. A liquid crystal panel having liquid crystal sandwiched between a pair of substrates; a polarizing plate disposed on one side of the liquid crystal panel; and a polarizing plate disposed on a side of the liquid crystal panel opposite to the polarizing plate. A reflective polarizer configured by alternately laminating a large number of first layers having in-plane refractive index anisotropy and second layers having no in-plane refractive index anisotropy; An electronic apparatus comprising, as a display unit, a liquid crystal device including a lighting device disposed on a side opposite to the liquid crystal panel with respect to the liquid crystal panel, wherein a vertical direction of a display screen in the liquid crystal device and a reflection polarizer are provided. An electronic device, wherein a reflection axis and a reflection axis are arranged substantially in parallel.