JP2000171619A - Anisotropic light scattering film and liquid crystal display device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an anisotropic scattering body of which the color of display light does not change depending on an observer's position by generating light scattering with respect to the incident light along the angle of the inclined direction and functioning as a mere transparent film with respect to the incident light with the angle vertical to the inclined direction. SOLUTION: Light scattering occurs with respect to the incident light 2 on the anisotropic light scattering film with an incident angle θ along the inclined direction of laminatedly distributed parts with different refractive indices, and with respect to the incident light 3 on the film with the angle vertical to the inclined direction, the film functions as a mere transparent film so as to make the incident light exit without scattering. Thus, the light, scattering film 1 has the light scattering selectivity dependent on the incident angle, generating light scattering with respect to the incident light 2 on the light scattering film 1 with the specified angle θ, and on the contrary, functioning as the mere transparent film with respect to the vertical incident light 3. As a result, the light 2 which needs scattering property and the light 3 which does not need scattering property can be separated by using the incident angle on the light scattering film 1 so as to reduce blur of the.display image.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light-scattering film having different anisotropy in light-scattering properties while having different scattering properties (or having an incident-angle selectivity) depending on the incident angle of light, and a light-scattering film having the same. The present invention relates to a liquid crystal display device which can be applied to improve visibility (brightness, contrast, and the like) of a display image and reduce power consumption of the display device.

The above-mentioned liquid crystal display device does not require a special light source such as a backlight or an edge light, and uses a reflection type liquid crystal of a type in which reflected light from ambient light (sunlight, indoor illumination light, etc.) is used as display light. Display device "and a" transmission type liquid crystal display device "of the type having the above-mentioned special light source.

[0003]

2. Description of the Related Art In a liquid crystal display device, a viewing angle at the time of observation is secured (that is, a display image is brightly displayed on the front surface of the display device), and uniform brightness is provided over the entire display screen. In order to make a display image visible, a light scattering film is arranged on the front of the device.
As a conventional light scattering film, a resin film whose surface is processed into a mat shape, a resin film containing a diffusing material inside, and the like are used.

[0004] In the case of a conventional resin film processed into a mat shape or a film containing a diffusing material inside, it is difficult in principle to have a function of changing scattering properties depending on the incident angle of incident light. It does not have such a function.

[0005] In the case of a light-scattering film whose surface is processed into a mat shape, the film surface is physically processed like a sandblaster treatment to form a matte surface, or chemically treated by dissolution treatment with an acidic or alkaline solution. A mat surface is formed. Therefore, it is difficult to control the light scattering property, and it is not possible to change the vertical and horizontal scattering properties, so that the light scattering cannot be made anisotropic.

[0006] In a light-scattering film containing a diffusing material therein, attempts have been made to control the refractive index, size, shape, etc. of the diffusing material in order to control the scattering properties. At present, the difficulty is high and it cannot be said that it is practically sufficient.

Therefore, the above-mentioned light-scattering film has no incident angle dependence of light-scattering and has little or no anisotropy of light-scattering, so that when used in a display device, unnecessary scattered light is generated. As a result, there is a problem that the brightness and contrast of the display are reduced or the displayed image is blurred.

On the other hand, as a proposal relating to a reflection type liquid crystal display device using a scattering plate having anisotropic light scattering, Japanese Patent Application Laid-Open No.
No. 01802 is known. The scattering plate disclosed in the above publication is a scattering plate having almost no back-scattering property and strong forward-scattering property, and selectively emits either the incident light to the liquid crystal display device or the output display light from the liquid crystal display device. It has the property of scattering.

In the above publication, the structure of the scattering plate is not specifically described, but is merely described as "the transparent fine particles are solidified with a transparent polymerizable polymer". In such a scattering plate, even if the scattering characteristics are given anisotropy (forward or backward), as in the above-mentioned “light scattering film containing a diffusing material inside”, the vertical and horizontal scattering It is difficult to control even the characteristics.

As a proposal for a transmission type liquid crystal display device using a hologram as a scattering plate, Japanese Patent Application Laid-Open No. Hei 9-152
No. 602 is known. The above proposal scatters display light emitted from a liquid crystal display device having a backlight, and employs a hologram as a scattering plate. Although it is easy to control the lateral scattering characteristics as well, the spectrum (wavelength dispersion) is inevitably involved, so that the color of the display light changes and is visually perceived as the viewpoint to be observed is moved. Will be.

[0011]

SUMMARY OF THE INVENTION According to the present invention, it is possible to provide anisotropic scattering characteristics (depending on the forward or backward direction and the incident angle) and to control the scattering characteristics in the vertical and horizontal scattering ranges. An object of the present invention is to provide an anisotropic scatterer that is easy and does not change the color of display light depending on an observation position, and a liquid crystal display device using the same.

[0012]

According to the anisotropic light-scattering film of the present invention, a portion having a different refractive index is distributed in an irregular shape and thickness inside the film, so that a light and shade pattern having a high or low refractive index is formed. By optimizing the size, shape, and distribution of the parts with different refractive indexes along the vertical and horizontal directions on the film surface and along the thickness direction of the film,
In addition to changing the scattering characteristics depending on the incident angle of incident light, light scattering in unnecessary directions is eliminated, and light is scattered only in necessary directions (ranges).

By applying such an anisotropic light-scattering film, a liquid crystal display device having high definition, high brightness and high contrast, and capable of displaying an image with little blur is provided.

In the anisotropic light-scattering film according to the first aspect, a portion having a different refractive index is distributed in an irregular shape and thickness inside the film, thereby forming a light and shade pattern having a high and low refractive index. And a portion having a different refractive index is a light scattering film having a structure that is distributed in a layered manner inclining with respect to the thickness direction of the film. On the other hand, light scattering occurs, and for light incident at an angle perpendicular to the tilt direction, the light scattering property has an incident angle selectivity, such as functioning as a mere transparent film. .

The anisotropic light-scattering film according to the second aspect is characterized in that the distribution of the refractive index is uniform in the direction in which the portions having different refractive indices are inclined in layers.

The anisotropic light-scattering film according to the third aspect is characterized in that the distribution of the refractive index is irregular in the direction in which the portions having different refractive indices are inclined in layers.

In the anisotropic light-scattering film according to the fourth aspect, the portions having different refractive indices are irregular in size, and each shape is vertically long (or horizontally long). Is characterized in that the light scattering characteristics are anisotropic in that the light scattering characteristics are horizontal (or vertical).

In the liquid crystal display device according to the present invention, the display pattern is changed by modulating transmission / non-transmission in accordance with an applied voltage to change the display pattern on the front side (observer side) or the back side (observer side). 5) At any position on the opposite side).
A light scattering film according to any one of the above.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 1 shows that the portions having different refractive indexes have irregular shapes.
FIG. 2 is an explanatory diagram showing a light scattering film 1 in which a light and shade pattern having a high and low refractive index (expressed in black and white in the figure) is formed and distributed in a thickness, and a left is a plan view and a right is a cross section. FIG.

As can be seen from the plan view, the shape of the portion having a different refractive index is horizontally long. Further, as can be seen from the cross-sectional view, the portions having different refractive indexes have a structure in which the portions are distributed in a layered manner inclining with respect to the thickness direction of the film. In FIG. 1, the distribution of the refractive index is uniform (the color does not change in the inclined direction) in the direction in which the portions having different refractive indexes are inclined in layers.

FIG. 2 is an explanatory view showing a light scattering film 1 according to another embodiment, in which the left is a plan view and the right is a sectional view. In FIG. 2, the shape of the portion having a different refractive index is vertically elongated, and the distribution of the refractive index is irregular in the direction in which the portion having a different refractive index is inclined in a layered manner (the color changes even in the inclined direction). Is).

First, the optical characteristics of the light-scattering film shown in FIGS. Light scattering occurs for light incident at an angle along the tilt direction in which portions having different refractive indices are distributed in layers (an angle θ from the perpendicular to the film, the direction of arrow 2 in the drawing). .

An angle perpendicular to the inclination direction (arrow 3 in the figure)
), It functions as a mere transparent film, and the incident light exits without being scattered.

Next, considering a plan view, if the shape of the portion having a different refractive index is vertically long (or horizontally long), when light incident on the portion is scattered and emitted, the light emitted from each portion is emitted. It has anisotropy such that the light scattering characteristic of the emitted light is horizontally long (or vertically long). In FIG. 1, the emitted light is scattered vertically because the shape is horizontal, and in FIG. 2, the emitted light is scattered horizontally because the shape is vertical. This will be described later in the step of manufacturing the light scattering film.

FIG. 3 is a graph showing an example of the incident angle dependency of the light scattering film 1 of the present invention. Solid line 4 in the figure
As shown in the figure, the haze value is 80% or more for light within a specific incident angle range (0 ° to 60 ° in the figure), and conversely, the incident angle is symmetrical (−60 ° to 0 ° in the figure). )
Has a haze value of 20% or less, which indicates the scattering angle dependency in the present specification.

Further, as described above, when the shape of the portion having a different refractive index is vertically long (or horizontally long), when light incident on that portion is scattered and emitted, the light emitted from each portion is Light scattering property is horizontal (or vertical)
It has anisotropy such that For example, when the shape is horizontally long as shown in FIG. 1, the scattered light emitted from the light scattering film is
As shown in FIG. 4, the distribution has a vertically long elliptical shape.

Next, the structure of the light scattering film 1 of the present invention will be described in detail. As described above, the light-scattering film 1 of the present invention has a light and shade pattern having a high or low refractive index by distributing portions having different refractive indexes in irregular shapes and thicknesses.

If the difference in the refractive index is too small, the scattering property deteriorates. On the other hand, if the difference is too large, light scattering occurs regardless of the incident angle of the light. It becomes difficult to have dependencies. For this reason, light scattering does not occur only by the refractive index difference on the surface, and the film needs to have an optimum refractive index difference that has sufficient scattering properties due to the thickness of the film.

In the present invention, the refractive index difference is appropriately selected from the range of 0.001 to 0.2 so that the above condition is satisfied. Similarly, the film thickness is set to 100 in accordance with the refractive index difference.
It is appropriately selected in the range of 0 μm to 1 μm.

As an example, a portion having a refractive index of 1.56 (refractive index difference 0.04) is distributed in a film having an average refractive index of 1.52 and a thickness of 20 μm to form a light and shade pattern. As a result, a light scattering film having sufficient scattering properties and incident angle selectivity could be obtained.

Since the refractive index difference that can be recorded is limited by the preparation method and the recording material, the thickness of the film is reduced when the refractive index difference is large, and the thickness is increased when the refractive index difference is small. Can be realized.

The size of the portions having different refractive indices is random and non-regular in order to cause light scattering, but the average size is 0.1 mm in diameter in order to have the required scattering.
It is appropriately selected from the range of 1 μm to 300 μm according to the scattering property required for each application.

As an example, by forming a light and shade pattern having an average size of 12 μm and having a high and low refractive index, about ± 4
A scattering property having a scattering spread of about 0 degree was obtained.

The distribution of portions having different refractive indices on the film surface is random and irregular in order to cause light scattering, but in order to have necessary scattering properties, the average refractive index of the entire film is required. Is assumed to be <n>, the probability distribution exhibits a normal distribution centered on <n>. Alternatively, the distribution may be such that the maximum value is obtained at the minimum value n _min of the refractive index n and the probability distribution monotonically decreases to the maximum value n _max of the refractive index, or the probability distribution monotonically increases.

<Embodiment 1> FIG. 5 is a sectional view conceptually showing a main part of a reflection type liquid crystal display device using the light scattering film of the present invention. It comprises a liquid crystal panel 5, a specular or scattering reflector 6 disposed on the back side (non-observer side), and a light scattering film 1 disposed on the front side (observer side) of the liquid crystal panel 5. Have been.

The reflection plate 6 is not provided separately from the liquid crystal panel 2 as shown in the figure, but may be provided inside the liquid crystal panel 2 as a reflection electrode serving also as an electrode for driving liquid crystal. Although the light scattering film 1, the liquid crystal panel 5, and the reflection plate 6 are illustrated as being separated from each other for convenience of explanation, they are actually stacked. In addition, depending on the type of liquid crystal, a polarizing plate, a retardation plate, or another optical film may be used, but is omitted.

The liquid crystal panel 5 has a general structure, modulates incident light according to the presence or absence of an applied voltage, and performs switching display between white / black (transmission / non-transmission).

On the other hand, as shown in the figure, the light scattering film 1 causes light scattering when the incident light 7 enters the light scattering film 1 from the front side of the liquid crystal panel 5, and the scattered light 8 The light is reflected by the reflecting plate 6 on the back side of the light-transmitting film, passes through the light scattering film 1, and is emitted to the front. At this time, the light scattering film 1 transmits the scattered light 9 to be emitted as it is without secondary light diffusion.

Therefore, the scattering property of the light-scattering film 1 does not cause unnecessary scattering when the display light is emitted, and the so-called 2
Since a superimposed image does not occur, blurring of the displayed image can be reduced. In addition, unnecessary scattering can be reduced by the scattering anisotropy, and the brightness and contrast of display can be improved.

<Embodiment 2> FIG. 6 is a sectional view conceptually showing a main part of a transmission type liquid crystal display device using the light scattering film of the present invention. It is composed of a liquid crystal panel 5, a backlight 10 arranged on the back side (non-observer side), and a light scattering film 1 arranged between the liquid crystal panel 5 and the backlight 10.

The light scattering film 1 scatters illumination light within a predetermined angle range of the light from the backlight 10 into a desired shape and makes the light enter the liquid crystal panel 5. By setting the predetermined angle range within an optimum incident angle (about ± 30 degrees) for retardation in the liquid crystal panel, display contrast can be improved.

On the other hand, the light outside the predetermined angle tends to transmit without being scattered by the light scattering film 1, but most of the light is totally reflected by the surface of the light scattering film 1 on the liquid crystal panel 5 side. Returning to the backlight 10 side, the scattered reflection is repeated again in the backlight 10, and as a result, most of the light from the backlight 10 becomes a component scattered and emitted by the light scattering film 1. Is not reduced.

<Embodiment 3> FIG. 7 is a sectional view conceptually showing a main part of another embodiment of a transmission type liquid crystal display device using the light scattering film of the present invention. LCD panel 5
And a backlight 10 disposed on the back (non-observer side) thereof, and a light scattering film 1 disposed on the front surface (observer side) of the liquid crystal panel 5.

The light scattering film 1 scatters outgoing light 13 within a predetermined angle range of display light from the liquid crystal panel 5 into a desired shape and emits it. By setting the predetermined angle range to be within the emission angle range (approximately ± 30 degrees) of the light that has undergone the optimal retardation in the liquid crystal panel, the display contrast can be improved.

On the other hand, the light 14 outside the predetermined angle is transmitted through the light scattering film 1 without being scattered, but the emitted light is directly transmitted without being scattered. The low-contrast image is not recognized by the observer.

Since the viewing angle at this time is specified by the anisotropy of light scattering of the light-scattering film 1, the viewing angle is not narrowed by the light-scattering film, but rather, the display light falls within an optimum range. Can be expanded.

Liquid crystal display panel 5 of liquid crystal display device of the present invention
, Any of a color display panel or a monochrome display panel equipped with color filters corresponding to the R, G, and B pixels may be used.

The liquid crystal display device of the present invention is not particularly limited to a liquid crystal driving method such as a TN method, an STN method, a guest host method, and a polymer dispersion type.

Hereinafter, the means for producing the light scattering film of the present invention will be described. The light scattering film of the present invention can be produced by an optical exposure means.

<Production Means 1> FIG. 8 is an explanatory view showing an example of an optical system for producing the light scattering film having the structure shown in FIG. 1 using a random mask pattern. UV light source 1
The ultraviolet light emitted from 5 is converted into parallel light 17 by a collimating optical system 16 and irradiated on a mask original 18. Mask original plate 18
Consists of a glass substrate 20 and a chromium pattern which is a random pattern.

A photosensitive material 19 is arranged in close contact with the surface of the mask original 18 opposite to the UV irradiation side, and the pattern of the mask original 18 is exposed and irradiated on the photosensitive material 19. At this time, since the UV parallel light 17 and the mask original plate 18 are arranged at a predetermined angle α as shown in the figure, the pattern exposure is performed at a predetermined angle in the photosensitive material 19. Since this angle corresponds to the inclination angle of the portion having a different refractive index in the light scattering film (that is, the scattering peak angle θ depending on the incident angle), the angle is 0 to 60 degrees depending on the application. It is appropriately selected within the range of the degree.

The photosensitive material 19 used here is U
A photosensitive material that can be recorded in the form of a change in the refractive index between an exposed portion and an unexposed portion of V light, and a material that has a higher resolving power than the density pattern to be recorded and can record a pattern in the thickness direction. Needs to be

As such a recording material, a photosensitive material for a volume hologram can be used, and a silver salt photosensitive material 8E56 for hologram manufactured by Agfa, a hologram photosensitive material HRF film manufactured by DuPont or gelatin dichromate, Polaroid Co., Ltd. DMP-128 recording material can be used.

The mask original 18 having a random pattern used in FIG. 8 is obtained by converting black-and-white pattern data generated by random number calculation using a computer into a metal chrome pattern 21 on a glass substrate 20 by a so-called photolithography technique.
What was etched was used. Of course, the method of producing the mask master is not limited to the above-described method, and it is well known that a similar mask can be produced by a lithography method using a squirrel plate.

<Production Means 2> FIG. 9 is an explanatory view showing an example of an optical system for producing a light-scattering film having the structure shown in FIG. 2 using a speckle pattern. Laser light source 2
The ground glass 25 is irradiated with the laser beam 24 emitted from 3. The photosensitive material 19 is disposed on the surface of the frosted glass 25 opposite to the laser irradiation side at a predetermined distance F, and a speckle pattern, which is a complex interference pattern generated by the laser light transmitted and scattered by the frosted glass 25, is applied to the photosensitive material 19. Is exposed to light.

At this time, the frosted glass 25 and the photosensitive material 19 are arranged at a predetermined angle α as shown in the figure, so that the speckle pattern is exposed at a predetermined angle in the photosensitive material. Since this angle corresponds to the inclination of a portion having a different refractive index in the light scattering film (that is, the scattering peak angle θ depending on the incident angle), the angle is about 0 to 60 degrees depending on the application. Is appropriately selected within the range.

The laser light source used for recording was an argon ion laser 514.5 nm, 488 nm or 45 nm.
Among the wavelengths of 7.9 nm, it can be appropriately selected and used according to the sensitivity of the photosensitive material. In addition, other than the argon ion laser, any laser light source having good coherence can be used. For example, a helium neon laser or a krypton ion laser can be used.

The speckle pattern is a bright and dark spot pattern generated when light having good coherence is scattered and reflected or transmitted on a rough surface, and light scattered by minute irregularities on the rough surface interferes in an irregular phase relationship. It is caused by

Description of “Light Measurement Handbook, Asakura Shoten, written by Toshiharu Tada et al., Issued on November 25, 1994” (p.266-p.26)
According to 8), in a speckle pattern in which the density and the phase show random values depending on the position, the size of the pattern is inversely proportional to the angle at which the diffusion plate is viewed from the photosensitive material, and the average diameter of the pattern is determined. Is done. Therefore, when the size of the diffusion plate is made larger in the vertical direction than in the horizontal direction,
The pattern recorded on the photosensitive material is finer in the vertical direction than in the horizontal direction.

In the speckle pattern by the manufacturing method using the optical system shown in FIG. 9, the wavelength λ of the laser beam to be used, the size D of the ground glass, and the distance F between the ground glass and the photosensitive material
Determines the average size d of the speckle pattern to be recorded. Generally, d is represented by the following equation. d = 1.2λF / D

The average length t of the speckle pattern in the depth direction is represented by t = 4.0λ (F / D) ² .

As described above, a light scattering film having a desired three-dimensional refractive index distribution can be obtained by optimizing the values of λ and F / D so as to have an optimum scattering property.

As an example, when λ = 0.5 μm, F / D =
Assuming that 2, d = 1.2 μm and t = 8 μm, the light and shade pattern on the film surface is distributed at an average of 1.2 μm, and the thickness direction of the film has an average of 8 μm in a direction according to the inclination angle. Will be distributed.

However, these sizes are merely average sizes. Actually, the sizes are variously large and small, and the portions having different refractive indices are inclined on the surface and in the depth direction. Thus, the light scattering film of the present invention as shown in FIG. 2 is obtained.

<Fabrication means 3> The light scattering film of the present invention described in claim 4 is fabricated using the optical system shown in FIG. 9 by changing the size of the frosted glass 25 in the vertical and horizontal directions to have a rectangular or elliptical shape. it can.

As an example, the size D of the frosted glass 25 differs between the vertical (y) direction and the horizontal (x) direction, and
Assuming that (Dx) = 2, (F / Dy) = 20 and other conditions are the same as above, the average size dx in the horizontal direction of the speckle pattern is 1.2 μm, and the average size dy = 1 in the vertical direction.
The speckle pattern has an average size of 2 μm and an aspect ratio of 1:10. By exposing this to light in the same manner as in <Production means 2>, a light-scattering film of the present invention having scattering anisotropy having different scattering properties in the vertical and horizontal directions is obtained.

The above-mentioned <Preparation means 1 to 3> are merely examples, and the present invention is not limited to this, or the light scattering film of the present invention can be realized by a production method other than optical exposure means. there is a possibility.

[0068]

According to the present invention, light incident on a light-scattering film at a predetermined angle causes light scattering, while light perpendicular to the light-scattering film functions as a transparent film. Therefore, light that requires scattering properties and light that does not require scattering properties can be separated by the angle of incidence on the film, and as a result, unnecessary scattering occurs when used in a display device or the like. This has the effect of improving the brightness, fineness, and contrast of the display without causing such a problem, and reducing the blur of the display image.

Further, when light is incident at an incident angle at which light scattering occurs, it is possible to have a scattering anisotropy in which the spread of the scattered light differs vertically and horizontally. for that reason,
The scattered light can be emitted only in a necessary direction, and as a result, when used in a display device, there is an effect of improving display brightness and contrast without generating unnecessary scattering.

[0070]

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a light scattering film of the present invention,
The left is a plan view and the right is a cross-sectional view.

FIG. 2 is an explanatory view showing a light scattering film of the present invention;
The left is a plan view and the right is a cross-sectional view.

FIG. 3 is a graph showing an example of the incident angle dependency of the light scattering film 1 of the present invention.

FIG. 4 is a diagram illustrating anisotropic light scattering of the light scattering film of the present invention.

FIG. 5 is a sectional view conceptually showing a main part of a reflection type liquid crystal display device using the light scattering film of the present invention.

FIG. 6 is a sectional view conceptually showing a main part of a transmission type liquid crystal display device using the light scattering film of the present invention.

FIG. 7 is a sectional view conceptually showing a main part of a transmission type liquid crystal display device using the light scattering film of the present invention.

FIG. 8 is an explanatory view showing an example of an optical system for producing a light scattering film having the structure shown in FIG. 1 using a mask pattern.

FIG. 9 is an explanatory view showing an example of an optical system for producing a light scattering film having the structure shown in FIG. 2 using a speckle pattern.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Light scattering film 2 ... Illumination light incident from a scattering direction 3 ... Illumination light incident from a transmission direction 4 ... Plot of measured haze value 5 ... Liquid crystal panel 6 ... Reflector 7 ... Peripheral illumination light 8 ... Scattered light 9 ... Emitted scattered light 10 Backlight 11 Illumination light within a predetermined angle range 12 Illumination light outside a predetermined angle range 13 Emitted light within a predetermined angle range 14 Emitted light outside a predetermined angle range 15 UV light source 16 Collimator Optical system 17 ... Parallel light 18 ... Mask original plate 19 ... Photosensitive material 20 ... Glass substrate 21 ... Chrome pattern 22 ... Optical fiber 23 ... Laser light source 24 ... Laser light 25 ... Glass glass 26 ... Beam expander 27 ... Collimator

Claims (5)

[Claims] 1. A light and shade pattern having a high and low refractive index is formed by distributing portions having different refractive indexes in an irregular shape and thickness inside the film. A light scattering film having a structure that is distributed in a layered manner with respect to the thickness direction of the film, and for light incident at an angle along the inclined direction, light scattering occurs; For light incident at an angle perpendicular to the tilt direction,
An anisotropic light-scattering film characterized by having a light-scattering property and an incident-angle selectivity, which functions as a simple transparent film. 2. The anisotropic light-scattering film according to claim 1, wherein the distribution of the refractive index is uniform in the direction in which the portions having different refractive indices are inclined in layers. 3. The anisotropic light-scattering film according to claim 1, wherein the distribution of the refractive index is irregular in the direction in which the portions having different refractive indices are inclined in layers. 4. The portions having different refractive indices are irregular in size, each shape is vertically elongated (or horizontally elongated), and the light scattering characteristic of each portion is horizontally elongated (or horizontally elongated).
The light-scattering film according to any one of claims 1 to 3, wherein the light-scattering film has anisotropy in light-scattering characteristics by being (vertically elongated). 5. A liquid crystal panel in which a display pattern is changed by modulating transmission / non-transmission in accordance with an applied voltage, at a position on the front side (observer side) or the back side (opposite side of the viewer). A liquid crystal display device having a configuration in which the light scattering film according to claim 1 is arranged.