JPH1068942A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an STN crystal display device low in visual angle dependency. SOLUTION: This device is provided with a liquid crystal cell 1 which is held by polarizing plates 4 to utilize the double refraction of the liquid crystals, a phase plate 3 which at least has a double refraction in the thickness direction of a liquid crystal layer 10 between the layer 10 and the plates 4 and a light diffusing means 3 which is laminated on the layer 10 so as to selectively diffuse the light beams in a prescribed direction. The layer 10 has liquid crystal molecules having spiral construction of more than 180 degrees and less than 360 degrees. Insertions are made for the plate 2 having a double refraction in the thickness direction of the layer 10 and the means 3, which selectively diffuses the light beams equivalent to approximately left and right directions with respect to a prescribed direction, between the plates 4 in which the polarizing axis is arranged in the direction that cross the adjacent oriented direction of the layer 10. Moreover, a light diffusing means 3 is provided so as to arrange the orientation center in the prescribed direction in the rear side of the cell 1 and to selectively diffuse the light beams which are equivalent to the direction slightly left and right directions of the front side.

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 in which the viewing angle dependence of a so-called STN liquid crystal display mode or the like is reduced.

[0002]

2. Description of the Related Art Conventionally, in a display device using a liquid crystal cell (Japanese Patent Application Laid-Open No. 60-107020), a viewing angle (observation direction) at which a certain level of contrast and brightness can be obtained.
Is limited. That is, even if the display can be clearly read by observing the display from the front side, when viewed from the oblique side or the back side, there is a disadvantage that the contrast is reduced or the contrast is inverted (negative / positive inversion).

[0003] Such viewing angle dependence is caused by a helical start position of the liquid crystal molecules determined by the rubbing direction of the liquid crystal molecules, a twist such as the direction of the helix, or a light passing direction to the liquid crystal layer. Due to differences in retardation due to light, characteristics due to the characteristics of the polarizing plate (such as the selectivity of the light oscillation direction), and characteristics resulting from the directivity of the light source that irradiates the liquid crystal with light. No.

In general, in a liquid crystal display device,
In consideration of the above viewing angle dependency, a design in which the position where the most display is easy to see falls within the normal viewing range of the user, for example, enhancing the contrast in the vertical direction of the center of the screen or slightly upward or downward (main observation direction) )).

[0005]

However, unlike a palmtop computer or a clock, a laptop computer, a monitor device, and the like do not always look at the display surface from the front / main observation direction. For example, there is a case where a user works while looking at a screen obliquely with a keyboard and materials at hand. Further, when the screen becomes large, for example, even if the display is observed from the front and the center part can be clearly read, the observation is made obliquely with respect to the display peripheral part. In such a case, there is a drawback that the contrast at the corner of the display surface is reduced or the contrast is inverted. Further, particularly in a so-called STN liquid crystal display, since the helical rotation angle of the liquid crystal molecules is large, the retardation to be corrected greatly changes depending on the azimuth, and it is difficult to correct. Further, since birefringence is used, coloring is caused due to excessive or insufficient correction.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and a liquid crystal cell sandwiched between polarizing plates so as to utilize the birefringence of liquid crystal, and the liquid crystal cell. A phase plate having birefringence at least in the thickness direction of the liquid crystal layer inserted between the liquid crystal layer and the polarizing plate; and a light diffusion layer laminated on the liquid crystal layer so as to selectively diffuse light in a predetermined direction. Means are provided.

Further, according to the present invention, the liquid crystal molecules are sandwiched by the alignment-treated substrate 11 and have a helical structure having a predetermined angle of 180 ° or more and 360 ° or less when no electric field is applied, and the center of the alignment direction is set to the predetermined direction. A liquid crystal layer 10, a polarizing plate 4 laminated on the liquid crystal layer 10 having a polarization axis or an absorption axis in a direction intersecting the alignment direction close to the liquid crystal layer, and inserted between the polarizing plate and the liquid crystal cell layer. A phase plate 2 having birefringence at least in the thickness direction of the liquid crystal layer, and a light diffusing means 3 laminated on the liquid crystal layer and selectively diffusing light corresponding to a substantially right and left direction with respect to the predetermined direction. In the STN display mode, preferably, the center of the alignment direction of the helical structure of the liquid crystal molecules is set in a predetermined direction on the back side (for example, φ =
−5 degrees, θ = 180 degrees), and the polarizing plate 4 and the liquid crystal layer 10
A phase plate 2 having birefringence (preferably nz = 0.2 to 0.8) at least in the thickness direction of the liquid crystal layer interposed between the liquid crystal layer and the liquid crystal layer, (E.g., ± θ1, 2 = ± 45 degrees) Light corresponding to a direction (eg, α central angle φ = 50 degrees) is selectively (0 degrees <α1, <
(90 degrees).

The present invention also provides a phase plate 2 having a birefringence (nz ≠ 0) at least in a thickness direction of a liquid crystal layer inserted between the polarizing plate and the liquid crystal layer in a so-called STN display mode. A light diffusing means 3 (preferably a view control in which an additive is mixed in a sheet material), which is laminated with the phase plate 2 between the liquid crystal layer 4 and the liquid crystal layer 10 and selectively diffuses light corresponding to a substantially right and left direction with respect to the main observation direction. Or a phase plate 2 having birefringence at least in the thickness direction of the liquid crystal layer inserted between the observation-side polarizing plate 4 and the liquid crystal layer 10 and the observation-side polarizing plate 4. A light diffusing means for selectively diffusing light corresponding to a substantially horizontal direction with respect to the main observation direction (preferably, a view control film in which a sheet material is stressed)
Is arranged.

[0009] Further features of the present invention will become more apparent in the following embodiments.

[0010]

FIG. 1 is a sectional view of a main part of a liquid crystal display device according to an embodiment of the present invention. Reference numeral 1 denotes a liquid crystal cell in which a liquid crystal layer is sandwiched between substrates so as to utilize birefringence. The phase plate 2, the light diffusing means 3, and the polarizing plate 4 are laminated on the (front) surface, and the phase plate 5, the polarizing plate 4, and the illuminating means 6 are arranged on the back surface as necessary. Have been. Among them, the phase plate 2 has birefringence at least in the thickness direction of the liquid crystal layer, and the light diffusing means 3 is a viewing angle control film, which selectively diffuses light in a predetermined direction, and is particularly preferably. It diffuses light substantially in the horizontal direction with respect to the viewing angle center direction, which is the main observation direction. Hereinafter, this will be described in more detail.

First, the liquid crystal cell 1 utilizes the birefringence of liquid crystal. In a typical so-called STN display mode, nematic liquid crystal molecules sandwiched between substrates subjected to alignment treatment have an angle of 180.degree. The liquid crystal layer 10 is formed in a spiral structure having a predetermined angle of 360 degrees or less.
The liquid crystal layer 10 is supported by a substrate 11 provided with an electrode 12 for applying an electric field for each pixel so as to be orthogonal to the inner surface, and has a polarization axis or an absorption axis in a direction intersecting with the close alignment direction of the liquid crystal layer 10. And polarizing plates 4 and 4 laminated on the liquid crystal layer 10. Thus, for example, a blue mode with a twist angle of 270 degrees (a so-called negative display of transmitted light on a dark blue background)
Is obtained. However, the present invention is not limited to the STN, and the polarization axis and the helical structure are not limited to such an angle, and any configuration may be used as long as the configuration utilizes birefringence interference of liquid crystal. Also, substrate 1
In 1, an alignment film 13 for forming a predetermined alignment in liquid crystal molecules is formed so as to sandwich the liquid crystal layer 10. However, when the substrate 11 is directly rubbed for alignment, the alignment film 13 may be omitted. it can. Further, a color filter layer (not shown) may be provided on the inner surface of the substrate 11 for performing color display.

Here, the viewing direction will be described.
As shown in FIG. 2, it is assumed that the line of sight C is at an angle inclined in a certain direction from a perpendicular line B of the surface A of the liquid crystal cell 1. As a method of expressing the line of sight C, an angle (reference) inclined from a perpendicular line B of the surface A of the liquid crystal cell is indicated, and is represented by φ. How much the projection direction of the line of sight C onto the surface A of the liquid crystal cell 1 is rotated from the front of the liquid crystal cell 1 is referred to clockwise as θ (or ± θ). Therefore, the line of sight C is expressed by the angle φ inclined from the perpendicular B and the rotation angle θ of the projection direction, but for convenience, 270 ° <= θ <= 90 ° and φ> = 0,
90 degrees <θ <270 degrees and φ <0 may be indicated.

In the liquid crystal display device shown in FIG.
In the case of a 0-degree helix, the orientation direction is crossed in an X-shape (± θ = ± 45 degrees) toward the display surface, and the helix direction is located on the back side (the front side is the rotationally open portion of the liquid crystal molecule helix). If you choose the polarization axis for optimal contrast,
The angle φ at which the central visual field is inclined from the perpendicular B is 0-3
The selected angle of 0 degree and the rotation angle θ of the projection direction are 170
It may be a selected predetermined direction of で き る 190 degrees. The liquid crystal molecules sandwiched between the substrates treated in this manner have a helical structure with a predetermined angle of 180 ° or more and 360 ° or less when no electric field is applied, and the center of the alignment direction is defined in a predetermined direction on the back side. By using the layer and the polarizing plate, the main observation direction, that is, the central visual field is set in a predetermined direction, the characteristic of the dependence of the viewing angle is determined, and the range of high contrast is specified.

The phase plate 2 is made of polycarbonate, polymethyl methacrylate, or the like. In this example, the phase plate 2 has a retardation in the film surface and shows a retardation in the thickness direction. A typical phase plate is shown in FIG.
As shown in the figure, the surface has in-plane birefringent refractive indices nx and ny, and with respect to the refractive index nz in the thickness direction, nx> ny.
= Nz, the film is uniaxially stretched. On the other hand, having birefringence also in the thickness direction means that the resin component is oriented in the thickness direction by, for example, devising a stretching method, so that nx> n as shown in FIG.
z> ny. In this way, the phase plate 2 having birefringence in the thickness direction is laminated so that the thickness direction and the thickness direction of the liquid crystal layer substantially coincide with each other, and is attached to the substrate 11 if necessary. When two phase plates 2 and 5 are used, both phase plates may be phase plates having birefringence in the thickness direction.
The use of a material having birefringence only in the thickness direction has a sufficient effect.

The liquid crystal cell 1 preferably has an illuminating means 6 on the back, and for example, a light guide plate 6 such as an acrylic resin flat plate.
1 and a linear light source 62 such as a cold cathode tube provided on the side surface of the light guide plate 61. Also, if necessary, the light guide plate 6
1 includes a front light diffusion sheet 63 and a back reflection sheet 64
In addition, a cylindrical reflection sheet (can also be used as the back reflection sheet 64) that covers the linear light source 62 can be added. Among them, the surface light diffusion sheet 63 is, for example,
It is composed of a plastic lens sheet such as polycarbonate, in which minute prisms having an apex angle of about 90 to 100 degrees are formed at a pitch of 10 to several hundreds of micrometers, and collects light incident from a substantially flat back surface. It is preferable to have a function of making the light with enhanced directivity. This is made of silicone or epoxy resin in a transparent plate such as acrylic resin, optical glass,
A microlens may be formed by a transparent material having a different refractive index such as silver chloride, or may be formed of a flat convex lens array, a laminate of a convex lens array and a concave lens array, or a laminate of a plurality of convex lens arrays or a concave lens array. You may comprise. As described above, it is more preferable that the illumination means 6 has directivity of the emitted light as a whole.

The light diffusing means 3 selectively diffuses light emitted from the liquid crystal cell 1 and has a central visual field (main observation direction).
The light in a direction substantially shifted left and right with respect to a predetermined direction set as is selectively diffused. It preferably consists of a visibility control film. Here, the direction shifted to the left and right means, for example, that a predetermined direction of the central visual field is (φ <0, θ = 18).
0) means that ± θ is approximately ± 90 degrees.
As shown in FIG. 4, the light diffusing means 2 has substantially the same quadrangular planar shape as the liquid crystal cell 1 and is used here by overlapping two sheets to select a predetermined range of incident light from incident light. It is composed of a polymer thin film having a special structure that is set so as to diffuse diffusely.

Here, the central viewing direction when the liquid crystal cell 1 is observed is such that the line of sight is located on the far side (φ <0) with respect to the perpendicular (φ = 0 degree) of the display surface (from the upper side to the lower side). ) Is set. The first light diffusing means 3A arranged above the liquid crystal cell 1 is provided with a perpendicular (φ =
0 degree), light incident in a predetermined angle range in the left (right) direction (for example, a range from a perpendicular (φ = 0 degree) to approximately left to α1 = about 30 degrees) is selectively diffused. The second light diffusing means 3B disposed on the upper surface of the first light diffusing means 3A includes:
Light incident in a right angle (left direction) direction with respect to a perpendicular line (preferably in a range from a perpendicular line (φ = 0 degree) to approximately rightward α2 = about 30 degrees) is selectively diffused. ing. α1 and α2 are centered at 30 degrees, preferably 90 degrees or less, and more preferably 20 to 70 degrees with respect to α central angle φ = 30 to 80 degrees. That is, the first light diffusion means 3
A incident direction θ1 of the light diffused by A and the second light diffusing means 3
The direction of incidence θ2 of the light diffused by B is different from each other, and preferably a direction rotated by 180 degrees or more (direction φ of the central visual field < When θ1> θ2 at 0, θ1−θ2> = 180
Degree), and this condition is suitable for widening the viewing angle to the left and right.

In a liquid crystal display device, the liquid crystal molecules are sandwiched between substrates subjected to alignment treatment, and have a helical structure having a predetermined angle of 180 ° or more and 360 ° or less when no electric field is applied, and the center of the alignment direction is set to a predetermined direction. If the polarizing plate is laminated on a liquid crystal layer having a polarization axis or an absorption axis in a direction that intersects the adjacent alignment direction of the liquid crystal layer, at least in the thickness direction of the liquid crystal layer inserted between the polarizing plate and the liquid crystal layer. By providing a phase plate having birefringence and a light diffusing means laminated on the liquid crystal layer and selectively diffusing light corresponding to a substantially right and left direction with respect to a predetermined direction, the viewing angle dependency is reduced.

Generally, in order to cancel the birefringent component of the optically anisotropic object, it is necessary to bring another optically anisotropic object having the same birefringent component to be projected, and this depends on the viewing angle direction in the on and off states. That is, it is only necessary to obtain a constant contrast difference without using the same. Therefore, in the present invention, the liquid crystal layer utilizing the birefringence or STN mode display, without considering the alignment of the liquid crystal molecules, the entire liquid crystal layer is regarded as one optically anisotropic, Considering the two states at the time of OFF, the path of light for selecting this birefringent component, another optically anisotropic body having the same birefringent component projected along the path, and diffusing light not along the path By a combination of means to
They are stacked with the idea that they have a wide viewing angle, high contrast, and can basically display in black and white.

Although the light diffusing means 3 is arranged inside the polarizing plate 4 in FIG. 1, it may be arranged outside the polarizing plate 4.
This arrangement also depends on the optical characteristics of the light selecting means 3. For example, if a polycarbonate sheet is significantly stressed to partially provide a physical optical crack, the viewing angle selectivity is increased. In this case, light coming from a specific direction is selectively diffused. However, at the same time, since this sheet has a large retardation, if the sheet is sandwiched between polarizing plates, the liquid crystal optical system is likely to collapse. Conversely, since a fine lens effect is provided, it is preferable to apply an anti-glare treatment to the surface and affix it to the outside of the polarizing plate, since the viewing angle scattering effect is combined and the viewing angle is further increased. On the other hand, a blind structure can be formed inside the sheet by adding chromium or the like to the sheet material (described later). In this case, since the retardation is another parameter, even if the light selecting means is sandwiched between the polarizing plates, the liquid crystal optical system is not broken, and the viewing angle limitation caused by the polarizing plates can be reduced.

That is, in the so-called STN display mode, the phase plate 2 having birefringence (nz ≠ 0) at least in the thickness direction of the liquid crystal layer inserted between the polarizing plate and the liquid crystal layer.
And a light diffusing means 3 (preferably, an additive is added to the sheet material), which is laminated with the phase plate 2 between the polarizing plate 4 and the liquid crystal layer 10 and selectively diffuses light corresponding to a substantially right and left direction with respect to the main observation direction. Or a phase plate 2 having birefringence in at least the thickness direction of the liquid crystal layer inserted between the observation-side polarizing plate 4 and the liquid crystal layer 10; Light diffusion means (preferably, a view control film (not shown) that stresses the sheet material) that selectively disperses light corresponding to a substantially left-right direction with respect to the main observation direction and is disposed on It is preferable.

As shown in FIG. 4, when each of the light diffusing means 3 observes the object through one of the light diffusing means 3A and 3B, for example, the light diffusing means 3 is at 0 to 30 degrees in one direction from the viewpoint. The range has an opaque state, and the other ranges have a function of selectively diffusing incident light so as to appear transparent. In the transparent state, each of the light diffusing means 2 has little reflection and absorption (for example, a total transmittance of 88%, of which a linear transmittance is 85%), and in the opaque state, the same light transmission as the transparent state. (E.g., 88% overall, of which 22% is a linear transmittance) and diffuses most of the transmitted light (e.g., 74% of incident light by combining transmitted and reflected scattering).
Is scattered) to form a ground glass-like appearance.

The polymer thin film constituting the light diffusing means 3 can be an acrylic resin molded product having, for example, a blind phase structure inside. When the internal structure of this molded article is observed with an optical microscope, a phase of a certain length is formed although it is cut in a folded shape in the surface observation, and about 50 μm from the film surface in the longitudinal section.
A phase structure having shades of light and shade is formed from a depth of m. The interval of such a phase structure is about 2 μm at the upper part of the film, and 3 to 4 μm at a depth of about 300 μm from the irradiation surface.
The distance gradually increases along the depth direction, but these may be set in accordance with the desired light diffusion direction and light diffusion degree. Also, by changing the direction of the phase structure and changing the inclination of the phase structure with respect to the light irradiation surface, the angle of expression of the opaque state can be freely set.
The incident angle range of the light to be diffused can be set as needed. Furthermore, there is a large difference in the composition distribution between the phase structures, and the refractive index is, for example, 1.55 for one phase,
In the other phase, the refractive index difference between the phases could be set as large as 1.51, and the difference between the phases was set as large as 0.04. These values can be formed so as to show the same value at any position in the depth direction of the film. The above-mentioned light scattering having a viewing angle dependence generated in the polymer thin film can be controlled largely due to the refractive index difference between the phase structures. If a polymer thin film constituting the light diffusing means 3 is to be obtained as a commercial product, an optical control film (product name "Lumisty") manufactured by Sumitomo Chemical Co., Ltd. It can be used by specifying its characteristics.

Each of the light diffusing means 3 is attached to the surface of the liquid crystal cell 1 (a phase plate may be attached and further attached to the phase plate) using an adhesive. The positioning of the two is performed so that the means 3 is adjusted in the direction in which the viewing angle of the liquid crystal cell 1 is to be improved. In the present embodiment, for example, a case in which the viewing angle when viewing the liquid crystal cell 1 from the lower side to the upper side is illustrated, and as shown in FIG. 4, the line of sight is fixed and the first light diffusing unit 3A is used. When observing, the range of the line of sight in which the object looks opaque is in the range of 0 to 30 degrees from the normal direction to the left (right) (when one point of the first light diffusing unit 3A is viewed from a different viewpoint, The first light diffusing means 3A is positioned and affixed to the liquid crystal cell 1 so that the range of the viewpoint which looks opaque is in the range of 0 to 30 degrees rightward from the normal direction.

Next, as shown in FIG. 4, the second light diffusing means 3B is positioned so that the left and right directions are reversed.
Is attached to the upper surface of the light diffusing means 3A. That is, light traveling from the liquid crystal cell 1 in the viewing angle direction to be improved is diffused by the first light diffusing means 3A, and of the diffused light, the light in the right (left) direction is converted into the second light diffusing light. The diffusion is performed again by the means 3B. Here, since the first and second light diffusing means 3A and 3B are both made of a thin film, it is possible to reduce the thickness of the display device, and to simplify the liquid crystal cell 1 using an adhesive or the like. Can be affixed to the device, so that the structure can be simplified.

Thus, the light diffusing means 3 is connected to the liquid crystal cell 1
As a result, data as shown in FIGS. 5 and 6 were obtained in the vertical direction of the liquid crystal cell 1. In the figure, four straight lines and seven concentric circles intersecting at the center are coordinate axes and scales. In this data measurement, the back side of the light introducing means 2 is illuminated by the surface illuminating means 4 having a predetermined luminance, and the illuminating means 6 makes the main direction of the light guided to the liquid crystal cell 1 relative to the liquid crystal cell 1. It is assumed that the directivity is substantially vertical (normal direction). 5 and 6
Is an isocontrast characteristic diagram showing the viewing angle dependency, but has trajectories E1 and E2 of the angle φ at which the contrast is inverted (negative / positive inversion) depending on the observation azimuth, and in FIG. STN contrast characteristics of uniaxial phase plate correction (contrast inversion (negative / positive inversion) angle φ
In the case of FIG. 6, it is superimposed on the contrast characteristic (trajectory C2 of the contrast inversion (negative / positive inversion) angle φ) of the STN having the phase plate 2 having birefringence in the thickness direction. It is displayed. Therefore, with the characteristic curves C1, C2, E1, and E2 as boundaries, the blue mode (negative) is displayed inside the characteristic curve (center of the circle).
Outside the characteristic curves C1, C2, E1, and E2, the data is inverted to positive and not read. A portion where the characteristic curve is interrupted and is not a closed curve (for example, a lexical direction at θ = 90 degrees) means that the contrast is not inverted even at φ = 70 degrees at that angle θ.

In the embodiment E1 shown in FIG. 5, the characteristic of the phase plate 2 is n
z = ((nx−nz) / (nx−ny)) = 0.45,
θ1 = 90 degrees, θ2 = 270 degrees, α1 = α2 = 50 degrees,
In the case of the embodiment E2 in FIG. 6, the characteristics of the phase plate 2 are nz = 0.45, θ1 = 45 degrees, and θ2 =
315 degrees, α1 = α2 = 50 degrees, and α center angle of 45 degrees. When a phase plate having birefringence in the thickness direction of the liquid crystal layer and a light diffusing means for selectively diffusing light corresponding to a direction substantially in the left-right direction are provided, it is shown that the good viewing angle region is widened. However, in particular, a phase having a birefringence in at least the thickness direction of the liquid crystal layer inserted between the polarizing plate and the liquid crystal layer is determined by setting the center of the orientation direction of the helical structure of the liquid crystal molecules in a predetermined direction on the back side. Light diffusing means laminated on the plate and the liquid crystal layer and selectively diffusing light corresponding to a direction facing left and right (ie, ± θ is not exactly ± 90 degrees, but a value smaller than ± 90 degrees). Is provided, the visual field range is further widened. In the normal contrast range of 5 or more (φ), for example, the vertical direction is 35 degrees to −15 degrees and the horizontal direction is 35 degrees to −40 degrees, but in the present invention, the vertical direction is 60 degrees to −35 degrees. It spread in the horizontal direction 55 degrees to -50 degrees.

As described above, with respect to the light emitted from the liquid crystal cell 1, the projected birefringence in the traveling direction is also compensated, and the light in a certain direction is selectively diffused to the object. In addition, the brightness and contrast in the good viewing direction (viewing angle improvement direction) were increased, and the brightness and contrast were flattened to expand the maximum value range. Stable display can be performed with a simple configuration.

[0029]

As described above, according to the present invention, since the compensation of the birefringence and the dispersion of the viewing angle can be performed at the same time, the viewing angle dependency can be reduced by making the brightness and contrast uniform.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a liquid crystal display device according to an embodiment of the present invention.

FIG. 2 is a perspective view illustrating the orientation of a liquid crystal cell.

FIG. 3 is an explanatory diagram of a refractive index ellipsoid for explaining a birefringence of a phase plate.

FIG. 4 is a perspective view showing an arrangement of a liquid crystal cell / phase plate and light diffusing means according to an embodiment of the present invention.

FIG. 5 is a characteristic diagram of a change in contrast according to an example of the present invention.

FIG. 6 is a graph showing contrast change characteristics according to the example of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 liquid crystal cell 2 phase plate 3 light diffusing means 3A first light diffusing means 3B second light diffusing means 4 polarizing plate 6 lighting means 10 liquid crystal layer

Claims (4)

[Claims] 1. A liquid crystal cell sandwiched between polarizing plates so as to utilize the birefringence of a liquid crystal, and at least a birefringence in a thickness direction of a liquid crystal layer inserted between the liquid crystal layer and the polarizing plate of the liquid crystal cell. A liquid crystal display device comprising: a phase plate having a property; and a light diffusing unit laminated on a liquid crystal layer so as to selectively diffuse light in a predetermined direction. 2. The liquid crystal molecules are sandwiched between substrates subjected to an alignment treatment, and have a helical structure having a predetermined angle of 180 ° or more and 360 ° or less when no electric field is applied, and the center of the alignment direction is set to a predetermined direction on the back side. A liquid crystal layer, a polarizing plate laminated on the liquid crystal layer having a polarization axis or an absorption axis in a direction intersecting the adjacent alignment direction of the liquid crystal layer, and at least a liquid crystal layer inserted between the polarizing plate and the liquid crystal layer. A liquid crystal comprising: a phase plate having birefringence in a thickness direction; and a light diffusing means laminated on the liquid crystal layer and selectively diffusing light corresponding to a direction toward the left and right in the near side. Display device. 3. A liquid crystal layer sandwiched between aligned substrates and having a helical structure having a predetermined angle of 180 ° or more and 360 ° or less when no electric field is applied to a liquid crystal layer, and a direction intersecting an adjacent alignment direction of the liquid crystal layer. A polarizing plate having a polarizing axis or an absorption axis and laminated on a liquid crystal layer, a phase plate having birefringence in at least the thickness direction of the liquid crystal layer inserted between the polarizing plate and the liquid crystal layer, and a polarizing plate. A liquid crystal display device comprising: a light diffusing unit that is laminated with the phase plate between liquid crystal layers and selectively diffuses light corresponding to a substantially right and left direction with respect to a main observation direction. 4. A liquid crystal layer sandwiched between aligned substrates and having a helical structure having a predetermined angle of 180 ° or more and 360 ° or less when no electric field is applied, and a liquid crystal layer in a direction intersecting an adjacent alignment direction. A polarizing plate laminated on a liquid crystal layer having a polarization axis or an absorption axis, a phase plate having birefringence at least in the thickness direction of the liquid crystal layer inserted between the observation side polarizing plate and the liquid crystal layer, 1. A liquid crystal display device comprising: a light diffusing means disposed on a polarizing plate for selectively diffusing light corresponding to a direction substantially right and left with respect to a main observation direction.