JPH1026765A - Liquid crystal display element, projection type liquid crystal display device, and substrate therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal display element which reduces diffraction effect caused by a periodic pattern formed on substrates holding a liquid crystal layer therebetween and has brightness and high contrast. SOLUTION: On the flanks of counter substrates 101 holding the liquid crystal layer or array substrates holding the liquid crystal layer 102 plural stripe-shaped electrodes 104 composed of transparent conductive films having thickness (d) are provided. The electrodes 104 are formed by adjusting a refractive index or a film thickness (d) so that difference between a first phase difference occurring when beams are transmitted through the transparent conductive film and a second phase difference occurring when beams are transmitted through the liquid crystal layer by the substantially same thickness (d) as the transparent conductive film is equal to integral multiple of wavelength λ of the transmitted light.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly to a projection type liquid crystal display. Further, the present invention relates to a substrate used for a liquid crystal display device.

[0002]

2. Description of the Related Art At present, liquid crystal display devices and plasma light emitting display devices have been receiving attention as small and light flat display devices replacing CRT display devices. In particular, a liquid crystal display device is considered as a favorite of a next-generation display device, and its technical development is being advanced in various fields.

In general, these flat panel display devices are of a self-luminous type in which a display element itself emits light in a display operation, and a transmittance in which a display element controls the transmittance of light incident from an independent light source in a display operation. It can be classified into control type.

For example, a plasma light emitting display belongs to a self-luminous type, and a liquid crystal display belongs to a transmittance control type display.

[0005] Therefore, in order to obtain excellent display quality with high brightness and high contrast, there is a demand for a liquid crystal display device having high light transmittance.

One of the factors that lowers the transmittance of a liquid crystal display element is that a periodic pattern formed on a substrate that sandwiches a liquid crystal becomes a diffraction grating and diffracts transmitted light.

There are other factors that lower the transmittance. For example, a typical liquid crystal panel represented by a twisted nematic type uses a polarizing plate to convert linearly polarized light into birefringent light. The light is incident on a liquid crystal layer exhibiting optical rotation. However, such a liquid crystal panel has a problem that the amount of light obtained from the light source is reduced to half when passing through the polarizing plate.

Recently, a liquid crystal display element which does not require a polarizing plate has been developed. In this liquid crystal display element, a liquid crystal layer of a polymer dispersion type in which a liquid crystal material is contained in a polymer resin or a fine particle dispersion type in which fine particles are contained in a liquid crystal material is sandwiched between a pair of transparent electrode substrates, It functions as a scattering-type modulation element that modulates the spatial propagation direction of light incident on the liquid crystal layer. In this case, the utilization efficiency of the light source light is improved as compared with the device using the polarizing plate.

The polymer-dispersed liquid crystal is set in a milky white light scattering state in which the incident light is scattered in a pixel region between the electrodes to which no voltage is applied, and the incident light is dispersed in the pixel region between the electrodes to which the voltage is applied. It is set to a transparent light transmission state that is hard to scatter.

For this reason, the scattering of each pixel region is controlled so that the intensity of the transmitted light and the reflected light changes in accordance with the video signal. For example, in a projection type liquid crystal display device, any one of the transmitted light and the reflected light is used. One is guided to the screen by the projection optical system.

The polymer-dispersed liquid crystal has restrictions on the shape of the polymer and the mixing ratio between the polymer and the liquid crystal layer. Further, the voltage applied from the outside has a limitation on the mixing ratio between the polymer and the liquid crystal layer. Further, since the voltage applied from the outside is divided into the polymer and the liquid crystal, only a part of the applied voltage is applied to the liquid crystal. For this reason, there is a problem that it is not possible to obtain a sufficient light scattering characteristic when trying to satisfy a driving characteristic requiring a sufficiently low driving voltage and a high response speed.

Further, in these systems, since the molecular arrangement of the liquid crystal is significantly different between the light scattering state and the light transmission state, hysteresis occurs in the electro-optical characteristics.

On the other hand, for example, by mixing a polymer with a hydrophobic substance in order to control the arrangement of liquid crystal molecules on the inner surface of the capsule, the arrangement of liquid crystal molecules in the light scattering state can be controlled to some extent to reduce hysteresis. However, this has the disadvantage of simultaneously reducing light scattering.

As described above, the conventional liquid crystal display device has problems such as low transmittance, narrow viewing angle characteristics, high driving voltage, and low response speed.

In order to solve such a problem, a light transmission state is realized by effectively forming a uniform molecular arrangement in each pixel, and a refraction lens effect or a light transmission effect is obtained by using two or more kinds of electric field directions. A method of realizing a light scattering state by forming a diffraction grating effect has been proposed.

Here, the refraction lens effect refers to an effect of refracting incident light by continuously changing the tilt of liquid crystal molecules in the thickness direction of the liquid crystal layer and continuously changing the refractive index of the liquid crystal layer. Say.

[0017] The diffraction grating effect, in the planar direction of the extraordinary refractive index n _e and ordinary index n _o and the liquid crystal layer of the liquid crystal molecules, by appearing in regularly alternating, diffraction by the liquid crystal layer lattice Are formed, and as a result, the parallel light is scattered.

A novel liquid crystal display element based on such a principle is proposed in Japanese Patent Application No. 6-172935. Japanese Patent Application No. 6-298496 proposes to further improve the characteristics of the above proposal.

These liquid crystal display elements can be applied as a projection type liquid crystal display device by guiding any one of transmitted light and scattered light to a screen by a projection optical system.

Japanese Patent Application Nos. 6-172935 and 6-29
In the proposal of 8496, in order to generate two or more types of electric field directions, electrodes are formed in stripes from a conductor portion and a non-conductor portion in units of a fine region of 50 μm or less per pixel. I have.

The refractive index of the conductor portion of the electrode is, for example, IT
When a transparent conductive film such as O (Indium Tin Oxide) is used as the transparent electrode, the value is about 2.0. The non-conductive part is the area where the transparent electrode is not formed,
An alignment film is formed and the sandwiched liquid crystal layer is filled,
The refractive indexes of the alignment film and the liquid crystal layer are about 1.5.

Therefore, since the conductive portion and the non-conductive portion have different refractive indices, a diffraction grating is formed by the stripe-shaped electrodes and the liquid crystal layer filled between the electrodes. Therefore, when the light transmission state is realized by effectively forming a uniform molecular arrangement in the liquid crystal layer, light is diffracted by the diffraction grating formed by the conductive portion and the non-conductive portion of the electrode.
There is a problem that the transmittance is reduced.

Thus, there is a problem that the transmitted light is diffracted by the periodic pattern formed on the substrate and the transmittance is reduced.

[0024]

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem. That is, an object of the present invention is to provide a bright and high-contrast liquid crystal display element in which a diffraction effect caused by a periodic pattern formed on a substrate sandwiching a liquid crystal layer is reduced.

Another object of the present invention is to provide a bright and high-contrast projection type liquid crystal display device provided with a liquid crystal display element in which a diffraction effect caused by a periodic pattern formed on a substrate sandwiching a liquid crystal layer is reduced. And

Another object of the present invention is to provide a substrate having a high transmittance which reduces diffraction.

[0027]

According to a first aspect of the present invention, there is provided a liquid crystal display device according to the present invention, wherein the liquid crystal display element is disposed so as to face a first substrate while maintaining an interval D, and the liquid crystal layer is interposed between the first substrate and the first substrate. A second substrate sandwiching and forming a plurality of pixel regions;
And a stripe-shaped electrode having a refractive index n and a thickness d formed in the pixel region of the substrate and having slits periodically arranged and having a minimum width larger than 2 Dtan (π / 9). In the liquid crystal display element, the stripe-shaped electrode allows the light to pass through a first phase difference generated when light passes through the conductive film and a medium existing between stripes of the stripe-shaped electrode. The second that sometimes occurs
Are arranged so that the refractive index n or the thickness d is adjusted so that the difference from the phase difference R becomes an integral multiple of the wavelength of the light.

Further, the liquid crystal display element of the present invention according to the second aspect is arranged so as to face the liquid crystal layer and the first substrate while keeping a distance D therebetween, and the liquid crystal layer is interposed between the first substrate and the first substrate. A second substrate sandwiching and forming a plurality of pixel regions;
And a stripe-shaped electrode having a refractive index n and a thickness d formed in the pixel region of the substrate and having slits periodically arranged and having a minimum width larger than 2 Dtan (π / 9). a liquid crystal display device having the stripe-shaped electrodes, a first phase difference R _i that occurs when light of the conductive film is transmitted, the light medium lying between the stripes of the first electrode the difference between the second phase difference R _j generated when the transmission _{is, 440nm ≦ | R i -R j} | such that ≦ 640 nm, that is disposed to adjust the refractive index n or the thickness d Features. In particular, when the incident light is white light, the refractive index n or the thickness d is adjusted so that the difference between the first phase difference and the second phase difference becomes 550 nm, which is the maximum visibility wavelength. Is also good.

Further, the liquid crystal display element of the present invention according to claim 3 is disposed so as to face the liquid crystal layer and the first substrate while maintaining a distance D therebetween, and the liquid crystal layer is disposed between the first substrate and the first substrate. A second substrate sandwiching and forming a plurality of pixel regions;
And a stripe-shaped electrode having a refractive index n and a thickness d formed in the pixel region of the substrate and having slits periodically arranged and having a minimum width larger than 2 Dtan (π / 9). a liquid crystal display device having the stripe-shaped electrodes, a first phase difference R _i that occurs when light of the conductive film is transparent, the medium lying between the stripes of the stripe electrode is the light the difference between the second phase difference R _j generated when the transmission is, when the wavelength of transmitted light was set to _{λ i, 0.8 × λ i ≦} | R i -R j | ≦ 1.2 × λ i So that the refractive index n according to the wavelength λ _i of the transmitted light
Alternatively, it is characterized by being arranged with the thickness d adjusted.

Further, the liquid crystal display element of the present invention according to the present invention is arranged so as to face the liquid crystal layer and the first substrate while maintaining a distance D therebetween, and to interpose the liquid crystal layer between the first substrate and the first substrate. A second substrate sandwiching and forming a plurality of pixel regions;
And a stripe-shaped electrode having a refractive index n and a thickness d formed in the pixel region of the substrate and having slits periodically arranged and having a minimum width larger than 2 Dtan (π / 9). a liquid crystal display device having the stripe-shaped electrodes, a first phase difference R _i that occurs when light of the conductive film is transparent, the medium lying between the stripes of the stripe electrode is the light the difference between the second phase difference R _j generated when the transmission is, when the wavelength of transmitted light was set to _{λ i, 0.8 × λ i ≦} | R i -R j | ≦ 1.2 × λ i So that the refractive index n according to the wavelength λ _i of the transmitted light
Alternatively, it is characterized by being arranged with the thickness d adjusted.

According to a fifth aspect of the present invention, there is provided a liquid crystal display device according to the present invention, wherein a second substrate sandwiching the liquid crystal layer between a liquid crystal layer and a first substrate; A first phase difference formed when light passes through the conductive film, the first phase difference being formed of a conductive film on a side surface of the substrate that sandwiches the liquid crystal layer, and the light substantially causing the liquid crystal layer to be substantially different from the conductive film; And a plurality of striped electrodes formed by adjusting the refractive index or the film thickness so that the difference from the second phase difference generated when the light passes through the same thickness becomes an integral multiple of the wavelength of the transmitted light. It is characterized by having.

According to a sixth aspect of the present invention, there is provided a liquid crystal display device according to the present invention, wherein the second substrate sandwiching the liquid crystal layer between the liquid crystal layer and the first substrate; A first phase difference generated when light passes through the conductive film, the first phase difference comprising a conductive film having a refractive index of n and a thickness of d on a side surface sandwiching the liquid crystal layer of the second substrate; The refraction is performed so that the difference from the second phase difference R that occurs when the liquid crystal layer transmits through the liquid crystal layer by substantially the same thickness as the conductive film is 440 nm ≦ | (n × d) −R | ≦ 640 nm. A striped electrode formed by adjusting the ratio n or the thickness d.

In particular, when the incident light is white light, the difference between the first phase difference and the second phase difference is the maximum luminous sensitivity wavelength of 55.
The refractive index n or the thickness d may be adjusted to be 0 nm.

According to a seventh aspect of the present invention, there is provided a liquid crystal display device according to the present invention, wherein the second substrate sandwiches the liquid crystal layer between the liquid crystal layer and the first substrate; A first phase difference generated when light passes through the conductive film, the first phase difference comprising a conductive film having a refractive index of n and a thickness of d on a side surface sandwiching the liquid crystal layer of the second substrate; When the wavelength of the light is λ _i , the difference from the second phase difference R that occurs when the liquid crystal layer transmits through the liquid crystal layer by substantially the same thickness as the conductive film is 0.8 × λ _i ≦ | (n × d) -R | that the refractive index n or the thickness d such that ≦ 1.2 × λ _i and and a stripe-shaped electrode formed adjusted according to the wavelength lambda _i of the light It is characterized by.

In the liquid crystal display device according to the present invention, a liquid crystal layer, a first region through which a first light having a first center wavelength is transmitted, and a second region having a second center wavelength. A first substrate having a pixel region composed of a second region through which the second light is transmitted; and a pixel region corresponding to the first substrate having the liquid crystal layer sandwiched between the first substrate and the first substrate. A second substrate and a conductive film having a refractive index of n and a thickness of d are formed in the first and second regions of the pixel region on the side surface of the first substrate or the second substrate which sandwich the liquid crystal layer. A first phase difference generated when light passes through the conductor film, and a second phase difference R generated when the light passes through the liquid crystal layer by substantially the same thickness as the conductor film. the difference between the, when the center wavelength of transmitted light was set to _{λ i, 0.8 × λ i ≦} | (n × d) -R | ≦ 1.2 × λ i The refractive index n or the thickness d so characterized by comprising a stripe-like electrodes were formed by adjusting in accordance with the wavelength lambda _i of the light transmitted through the first and second regions.

According to a ninth aspect of the present invention, there is provided a liquid crystal display device according to the ninth aspect, wherein a second substrate forming a plurality of pixel regions by sandwiching the liquid crystal layer between the liquid crystal layer and the first substrate. Sandwiching a plurality of filters formed in the respective pixel regions of the first or second substrate so as to transmit a plurality of lights having different center wavelengths, and the liquid crystal layer of the first or second substrate. A conductive film having a refractive index of n and a thickness of d, and a first phase difference generated when light passes through the conductive film, substantially corresponding to the conductive film. When the wavelength of the transmitted light is λ _i , the difference from the second phase difference R generated when the light passes through the liquid crystal layer by the same thickness is 0.8 × λ _i ≦ | (n × d ) -R | ≦ 1.2 × λ _i become so transparent that the refractive index of the wavelength of light in accordance with the lambda _i n or thickness d And characterized by including a stripe-shaped electrode formed by adjusting.

A liquid crystal display device according to the present invention as set forth in claim 10, wherein the second substrate sandwiching the liquid crystal layer between the liquid crystal layer and the first substrate; the first substrate or the second substrate. A first phase difference R _i generated when light passes through the first medium, the first phase difference R _i comprising a first medium and a second medium periodically arranged on a side surface sandwiching the liquid crystal layer; The refractive index or thickness of the first medium or the second medium is such that the difference between the light and the second phase difference _Rj generated when the light passes through the second medium is an integral multiple of the wavelength of the light. Characterized by having a diffraction grating formed by adjusting.

Further, in the liquid crystal display device according to the present invention, a second substrate sandwiching the liquid crystal layer between the liquid crystal layer and the first substrate; A first phase difference R _i generated when light passes through the first medium, comprising a first medium and a second medium periodically arranged on the side of the substrate that sandwiches the liquid crystal layer. , the difference between the second phase difference R _j wherein light is generated when passing through the second _{medium, 440nm ≦ | R i -R j} | such that ≦ 640 nm first medium or the second medium Characterized by having a diffraction grating formed by adjusting the refractive index or thickness.

In particular, when the incident light is white light, the difference between the first phase difference and the second phase difference is 55, which is the maximum luminous efficiency wavelength.
The refractive index n or the thickness d may be adjusted to be 0 nm.

According to a twelfth aspect of the present invention, there is provided a liquid crystal display element according to the present invention, wherein a second substrate sandwiching the liquid crystal layer between the liquid crystal layer and the first substrate; A first phase difference R _i generated when light passes through the first medium, comprising a first medium and a second medium periodically arranged on the side of the substrate that sandwiches the liquid crystal layer. The difference between the light and the second phase difference _Rj that occurs when the light passes through the second medium is:
When the wavelength of the light was _{λ i, 0.8 × λ i ≦} | R i -R j | such that ≦ 1.2 × λ _i, the first medium according to the wavelength lambda _i of the light Alternatively, a diffraction grating formed by adjusting a refractive index or a thickness of the second medium is provided.

According to a thirteenth aspect of the present invention, there is provided a liquid crystal display device having a liquid crystal layer, a first region through which first light having a first central wavelength is transmitted, and a second region having a second central wavelength. A first region having a pixel region composed of a second region through which the second light is transmitted;
And a second substrate having the pixel region corresponding to the first substrate and sandwiching the liquid crystal layer between the first substrate and the second substrate.
And a first medium and a second medium periodically arranged in a first region and a second region on a side surface of the first substrate or the second substrate that sandwiches the liquid crystal layer. , A first phase difference R _i generated when light passes through the first medium,
When the wavelength of the light is λ _i , the difference between the light and the second phase difference R _j generated when the light passes through the second medium is 0.8 × λ _i ≦ | R _i −R _j | ≦ 1.2 ×, characterized in that the refractive index or thickness of the first medium or the second medium according to the wavelength lambda _i of the light is formed by adjusting such that the lambda _i.

According to a fourteenth aspect of the present invention, one of the first medium and the second medium of the liquid crystal display element according to the tenth to thirteenth aspects of the present invention is made of a conductor. It is characterized by having. The conductor may be formed of, for example, ITO (Indium Tin Oxide).

Further, in the liquid crystal display device according to the present invention, the first medium of the liquid crystal display device according to the present invention is formed of ITO, and the second medium is sandwiched between the substrates. It is characterized by comprising a liquid crystal layer.

According to a sixteenth aspect of the present invention, the maximum width of the stripes and the maximum width of the slit of the stripe-shaped electrode constituting the liquid crystal display element according to the first to thirteenth aspects are 50 μm or less. It is characterized by.

According to a seventeenth aspect of the present invention, there is provided a liquid crystal display device according to any one of the first to thirteenth aspects, wherein the stripe region of the striped electrode formed on the first substrate constituting the liquid crystal display element is the first one. It is characterized by being arranged so as to face the slit region of the striped electrode formed on the second substrate.

That is, in the liquid crystal display element of the present invention, the diffraction effect caused by the periodic pattern of the transparent conductive film formed on the substrate holding the liquid crystal layer is determined by the refractive index or the thickness of the medium forming the diffraction grating. It is reduced by adjusting according to the wavelength of transmitted light.

The medium need not be formed of a single substance. For example, the first medium may be formed from ITO and an alignment film.

Further, for example, the second medium may be formed from a constituent material of the liquid crystal layer and an alignment film.

Further, the first medium may be a light-transmitting conductor, and the second medium may be formed of a light-transmitting non-conductor.

The same applies to the case where there is a medium constituting a diffraction grating in addition to the first medium and the second medium.

That is, in the present invention, the refractive index or the thickness of the medium forming the diffraction grating is adjusted so as to minimize the diffraction effect of the diffraction grating formed on the substrate of the liquid crystal display device.

In the liquid crystal display device of the present invention, the diffraction effect produced by the periodic pattern of the transparent conductive film formed on the substrate holding the liquid crystal layer is transmitted through the refractive index or the thickness of the transparent conductive film. It is reduced by adjusting according to the wavelength of light.

FIG. 1 is a diagram schematically showing an enlarged part of a counter substrate of the liquid crystal display device of the present invention.

The opposite substrate 101 of the liquid crystal display device 100
The liquid crystal layer 102 is sandwiched between an array substrate (not shown). As the counter substrate 101, a transparent conductive film 104 is formed on a transparent insulating substrate 103.
4 and the alignment film 1 so as to cover the entire surface of the transparent insulating substrate 103.
05 is formed. The transparent conductive film 104 is formed as a striped electrode having a striped pattern (see FIG. 3).

The stripe-shaped electrodes are not limited to those illustrated in FIG. 3, but may be any electrodes having a stripe-like pattern arranged periodically, such as the electrodes illustrated in FIGS.

In the liquid crystal display device having the transparent conductive film 104 arranged in such a periodic pattern, the first medium and the second medium having different refractive indexes, that is, the transparent conductive film 104 and the liquid crystal layer 102 form a diffraction grating.

Since the refractive index of the transparent conductive film is generally different from that of the liquid crystal layer, the phase difference generated when light passes through the A region 106 on which the first medium on which the transparent conductive film is formed is formed. (Retardation) is different from the phase difference generated when the light passes through the B region 107 where the transparent conductive film is not formed, that is, the liquid crystal layer having substantially the same thickness as the transparent conductive film as the second medium. It is.

In the liquid crystal display element of the present invention, the refractive index or the thickness of the medium forming the diffraction grating, such as the thickness of the transparent conductive film 104, is adjusted to reduce the retardation of each region and the diffraction intensity of transmitted light. It is formed so as to be optimized to be small.

That is, assuming the wavelength λ of the incident light and the intensity I ₀ ,
Assuming that the thickness of the transparent conductor film 104 is d, the refractive index is n ₁ , and the refractive index of the liquid crystal layer 102 is n ₂ , the diffraction intensity I by this diffraction grating is approximately I to sin ² (((n ₁ −n ₂ ) × d × π) / λ) × I
It becomes ₀ . Therefore, ((n ₁ −n ₂ ) × d × π) / λ
Is adjusted to be an integer.

Of course, the transparent conductive film 104 or the liquid crystal layer 102 having an appropriate refractive index may be appropriately selected and the refractive index may be adjusted to reduce the diffraction intensity.

Since the thickness of the orientation film 105 is much smaller than that of the transparent conductive film, the contribution to diffraction is very small.

When there is a substance (medium) that contributes to diffraction of incident light other than the transparent conductive film and the liquid crystal layer, the thickness and the refractive index of the substance may be adjusted accordingly.

That is, when the wavelength of the incident light is λ,
The retardation R _i in the A region 106 where the first medium is formed is represented by Σ (n _i × d _i ), where i = 1, 2,
.., K), and when the retardation R _j in the B region 107 in which the second medium is formed is Σ (n _j × d _j ) (where j = 1, 2,..., L), 0.8 × λ ≦ | R _i −R _j | ≦ 1.2 × λ, more preferably, | R _i −R _j | = λ, that is, the diffraction consisting of the A region 106 and the B region 107 The refractive index or thickness of the first medium and the second medium, that is, the refractive index or the thickness of the substance contributing to diffraction, is adjusted in accordance with the wavelength of the incident light so that the retardation of the incident light passing through the grating becomes substantially equal. I just need.

Here, 0.8 × λ ≦ | R _i −R _j | ≦
In the range of 1.2 × λ, a tolerance of 20% is set.

For example, the present invention can be applied to the case where the retardation due to a transparent insulating material or the like filling the slit portions of the alignment film and the stripe-shaped electrode is considered.

FIG. 35 is a diagram schematically showing an example of a liquid crystal display device in which a slit region of a striped electrode is filled with a transparent insulating material such as SiOx instead of a liquid crystal layer. A transparent electrode 3502 in the form of a stripe is provided on the surface of the transparent insulating substrate 3501 sandwiching the liquid crystal 3505, and a transparent insulating material 3 is provided in the slit region of the stripe-shaped electrode 3502.
503 are filled. Reference numeral 3504 denotes an alignment film.

Assuming that the stripe-shaped electrode is the first medium, the second medium is a transparent insulating material, and the refractive index or thickness of the second medium is such that the retardation of the incident light transmitted through the diffraction grating is reduced. The first medium and the second medium are adjusted according to the wavelength of the incident light so that they are substantially equal.

Although the orientation film may be considered as a medium, its contribution is generally very small.

In FIG. 1, the description has been made using the opposing substrate.
The same applies to the case where a transparent conductive film having a periodic pattern is formed on the array substrate side on which a thin film transistor (TFT) is formed.

Further, as described above, the transparent conductive film provided with the thickness or the refractive index adjusted so as to reduce the diffraction intensity of the incident light is formed on both the substrates sandwiching the liquid crystal. You may.

As described above, the liquid crystal display device having the transparent conductive film arranged so that the thickness or the refractive index is optimized so as to minimize the diffraction intensity is obtained by forming the transparent conductive film in a periodic pattern. In this case, the transmittance does not decrease due to diffraction.

When the wavelength transmitted through the liquid crystal display element is white light, | R _i -R _j |
The refractive index or the thickness of the transparent conductive film may be adjusted so as to be 50 nm. 440 nm ≦ | R _i -R
_{If j} | ≦ 640 nm, the diffraction intensity is sufficiently small.

The light transmitted through the liquid crystal display element has a wavelength λ.
_{In the case of i} monochromatic light, the refractive index or thickness of the transparent conductive film may be adjusted so that | R _i -R _j | becomes λ _i . 0.8 × λ ≦ | R _i −R _j | ≦ 1.
In the range of 2 × λ, the diffraction intensity is sufficiently small.

When the light transmitted through the liquid crystal display element is monochromatic light having a plurality of wavelengths λ _i , the light is transmitted so that | R _i −R _j | becomes λ _i in accordance with each wavelength. The refractive index or the thickness of the conductive film may be adjusted.
The diffraction intensity is sufficiently small in the range of 0.8 × λ ≦ | R _i −R _j | ≦ 1.2 × λ.

The plurality of monochromatic lights may adjust the refractive index or the thickness of the transparent conductive film in accordance with the wavelength λ _{i of} each of the three primary colors that enable color display.

In addition to the three primary colors red, green and blue, the refractive index or thickness of the transparent conductive film may be adjusted in accordance with the three primary colors of the absorbing medium, cyan, magenta and yellow.

Further, one pixel region of the liquid crystal display element has a wavelength λ.
_{When i} is composed of a plurality of regions through which a plurality of monochromatic lights different from each other are transmitted, the refractive index or the thickness of the periodic pattern of the transparent conductive film may be adjusted for each region. .

For example, when one pixel is composed of a plurality of regions each transmitting red, green and blue, ΔR (= | R _i −R _j |) is a red wavelength (for example, 700 nm) in the red transmission region. ) In the green transmission region.
Becomes a green wavelength (for example, 546.1 nm),
ΔR is a green wavelength (for example, 435.8) in the blue transmission region.
nm) may be formed by optimizing the refractive index or the thickness of each transparent conductive film.

The same applies to a case where a plurality of regions through which a plurality of monochromatic lights having different wavelengths λ _i are transmitted are formed by, for example, a color filter or a microlens array.

The substrate on which the transparent conductive film is formed by optimizing the refractive index or the thickness so as to minimize the diffraction intensity as described above should have an effective uniform molecular arrangement in each pixel. Realizes a light transmitting state, and realizes a light scattering state by obtaining a refraction lens effect and a diffraction grating effect with two or more types of electric field directions.
Japanese Patent Application No. 6-298, in which the liquid crystal display element proposed in 172935 and the values of the angle of the oblique electric field, the width of the conductor portion and the non-conductor portion of the electrode, the gap between the electrodes, Δnd, etc. are optimized.
496 may be applied to a liquid crystal display element or the like.

The liquid crystal display device of the present invention is suitable for a liquid crystal display device constituting a projection type liquid crystal display device.

A projection type liquid crystal display device according to the present invention, wherein: (a) a light source; (b) a liquid crystal layer; and a second substrate sandwiching the liquid crystal layer between the first substrate. And the first
A first phase difference generated when light passes through the conductive film, the first phase difference being formed of a conductive film on a side surface of the substrate or the second substrate that sandwiches the liquid crystal layer; A plurality of layers formed by adjusting the refractive index or the film thickness so that the difference from the second phase difference generated when the light is transmitted by substantially the same thickness as the conductor film is an integral multiple of the wavelength of the light. (C) a first optical system disposed between the light source and the liquid crystal display element and configured to collimate light from the light source and enter the liquid crystal display element; ,
(D) disposed between the liquid crystal display element and a projection surface;
A second optical system for projecting the light transmitted through the liquid crystal display element onto the projection surface.

According to a nineteenth aspect of the present invention, there is provided a projection type liquid crystal display device comprising: (a) a light source; (b) a liquid crystal layer;
A first substrate having a pixel region including a first region through which a first light having a center wavelength of the first wavelength transmits and a second region through which a second light having a second center wavelength transmits; A second substrate having the pixel region corresponding to the first substrate sandwiching the liquid crystal layer between the first substrate and the second substrate; and a side surface sandwiching the liquid crystal layer of the first substrate or the second substrate. The first and second regions of the pixel region are formed of a conductive film having a refractive index of n and a thickness of d. When the center wavelength of the transmitted light is λ _i , the difference between the second phase difference R and the second phase difference R generated when the layer is transmitted by substantially the same thickness as the conductor film is 0.8 × λ _i ≦ | (n × d) -R | ≦ 1.2 × light transmitted through the first and second regions of the refractive index n or the thickness d such that the lambda _i The liquid crystal display device and, (c) above with the light source and the parallel light source light disposed between the liquid crystal display device liquid crystal having a striped electrode formed respectively adjusted according to the wavelength lambda _i A first optical system that enters the display element, and (d) a second optical system that projects light transmitted through the liquid crystal display element disposed between the liquid crystal display element and the projection plane onto the projection plane. And characterized in that:

According to a twentieth aspect of the present invention, there is provided a projection type liquid crystal display device comprising: (a) a light source; (b) a liquid crystal layer;
A second substrate that forms a plurality of pixel regions by sandwiching the liquid crystal layer between the first and second substrates; and a plurality of lights having different center wavelengths are transmitted through the respective pixel regions of the first or second substrate. And a conductive film having a refractive index of n and a thickness of d in a region corresponding to each of the filters on a side surface of the first substrate or the second substrate that sandwiches the liquid crystal layer. A difference between a first phase difference generated when light passes through the conductive film and a second phase difference R generated when light passes through the liquid crystal layer by substantially the same thickness as the conductive film. , when the wavelength of transmitted light was set to _{λ i, 0.8 × λ i ≦} | accordance with the wavelength of the transmitted light so as to ≦ 1.2 × λ _i to _{λ i | (n × d)} -R A liquid crystal display element having a stripe-shaped electrode formed by adjusting the refractive index n or the thickness d by using the liquid crystal display; (D) a first optical system, which is provided between the liquid crystal display element and the liquid crystal display element and which converts the light from the light source into parallel light and enters the liquid crystal display element; A second optical system for projecting light transmitted through the liquid crystal display element onto the projection surface.

According to a twenty-first aspect of the present invention, there is provided a projection type liquid crystal display device comprising: (a) a light source; (b) a liquid crystal layer;
A second substrate sandwiching the liquid crystal layer between the first substrate and the second substrate, and a conductive film having a refractive index of n and a thickness of d provided on a side surface of the first substrate or the second substrate that sandwiches the liquid crystal layer. A first phase difference that occurs when light passes through the conductor film, and a second phase difference that occurs when light passes through the liquid crystal layer by substantially the same thickness as the conductor film. the difference between the R is, when the wavelength of the light was _{λ i, 0.8 × λ i ≦} | a refractive index n or the thickness such that _{≦ 1.2 × λ i | (n} × d) -R a plurality of liquid crystal display device having a stripe-shaped electrode formed by adjusting according to d to the wavelength lambda _i of the light is, disposed between the liquid crystal display device (d) and the light source, the light source A first optical system that splits light into a plurality of parallel lights having different center wavelengths λ _i and enters the corresponding liquid crystal display elements, respectively; A second optical system disposed between the display element and the projection surface, for combining light transmitted through each of the plurality of liquid crystal display elements and projecting the combined light onto the projection surface.

According to a twenty-first aspect of the present invention, there is provided a projection type liquid crystal display device according to the present invention, wherein: (a) a light source; (b) a liquid crystal layer; and a second substrate sandwiching the liquid crystal layer between the first substrate. And a first medium and a second medium periodically arranged on a side of the first substrate or the second substrate sandwiching the liquid crystal layer, when light passes through the first medium. The resulting first phase difference R _i
And a refractive index of the first medium or the second medium such that a difference between the light and the second phase difference _Rj generated when the light passes through the second medium is an integral multiple of the wavelength of the light. A liquid crystal display element comprising a diffraction grating formed by adjusting the thickness; and (c) converting the light source light disposed between the light source and the liquid crystal display element into parallel light. A first optical system that enters the liquid crystal display element, and (d) a second optical system that is disposed between the liquid crystal display element and the projection plane and that projects light transmitted through the liquid crystal display element onto the projection plane. And the optical system of (1).

Further, the projection type liquid crystal display device of the present invention according to the twenty-third aspect provides (a) a light source, (b) a liquid crystal layer, and a first liquid crystal layer.
A first substrate having a pixel region including a first region through which a first light having a center wavelength of the first wavelength transmits and a second region through which a second light having a second center wavelength transmits; A second substrate having the pixel region corresponding to the first substrate that sandwiches the liquid crystal layer between the first substrate and the second substrate; and a second side of the first substrate or the second substrate that sandwiches the liquid crystal layer. A first phase difference R _i generated when light passes through the first medium, comprising a first medium and a second medium periodically arranged in the first region and the second region; When the wavelength of the light is λ _i , the difference between the light and the second phase difference R _j generated when the light passes through the second medium is 0.8 × λ _i ≦ | R _i −R _j | ≦ 1.2 × first medium or diffraction grating formed by adjusting the refractive index or thickness of the second medium according to the wavelength lambda _i of the light so that the lambda _i A liquid crystal display element characterized by comprising,
(C) a first light source, which is provided between the light source and the liquid crystal display element and is incident on the liquid crystal display element by converting the light into parallel light;
And (d) a second optical system disposed between the liquid crystal display element and the projection surface, for projecting light transmitted through the liquid crystal display element onto the projection surface. And

According to a twenty-fourth aspect of the present invention, there is provided a projection type liquid crystal display device comprising: (a) a light source; (b) a liquid crystal layer;
A second substrate sandwiching the liquid crystal layer between the first substrate and the second substrate, and a first medium periodically arranged on a side surface of the first substrate or the second substrate sandwiching the liquid crystal layer; consisting of a medium, first the phase difference R _i that occurs when light passes through the first medium, the light is a difference between the second phase difference R _j occurring when passing through the second medium , when the wavelength of the light was _{λ i, 0.8 × λ i ≦} | R i -R j | such that ≦ 1.2 × λ _i, first according to the wavelength lambda _i of the light A liquid crystal display device comprising a diffraction grating formed by adjusting the refractive index or the thickness of the medium or the second medium;
(D) a first light source disposed between the light source and the liquid crystal display element, which splits the light into a plurality of parallel lights having different center wavelengths λ _i and enters the corresponding liquid crystal display elements.
And (e) a second optical system arranged between the liquid crystal display element and the projection surface, for combining lights transmitted through the plurality of liquid crystal display elements and projecting the combined light on the projection surface. And characterized in that:

According to a twenty-fifth aspect of the present invention, there is provided a projection type liquid crystal display device according to any one of the eighteenth to twenty-fourth aspects. Maximum slit width is 50μ
m or less.

A liquid crystal display element according to a twenty-sixth aspect of the present invention provides a projection type liquid crystal display device according to any one of the eighteenth to twenty-fourth aspects, wherein the striped electrode is formed on a first substrate. Is formed so as to face the slit region of the striped electrode formed on the second substrate.

The substrate of the present invention according to claim 27 is a substrate for holding a liquid crystal layer, wherein a transparent insulating base material and a side surface of the transparent insulating base material for holding the liquid crystal layer are periodically arranged. Light composed of the arranged first medium and second medium,
The difference between the first phase difference R _i generated when the light passes through the medium and the second phase difference R _j generated when the light passes through the second medium is an integer of the wavelength of the transmitted light. A diffraction grating formed by adjusting the refractive index or the thickness of the first medium or the second medium so as to increase the magnification twice.

The substrate of the present invention according to claim 28 is a substrate for holding a liquid crystal layer, comprising a transparent insulating film and a conductive film on the side of the transparent insulating film for holding the liquid crystal layer. A difference between a first phase difference generated when light passes through the conductive film and a second phase difference generated when light passes through the liquid crystal layer by substantially the same thickness as the conductive film. And a stripe-shaped electrode formed by adjusting the refractive index or the film thickness so as to be an integral multiple of the wavelength of the light.

As described above, the present invention is formed so as to optimize the retardation in each region so as to minimize the diffraction intensity of the diffraction grating by the periodic pattern formed by the plurality of regions having different refractive indexes. ing.

Even when a light transmitting state is realized by effectively aligning the liquid crystal layer in the liquid crystal layer, the diffraction intensity of the transmitted light by the conductive portion and the non-conductive portion of the striped electrode is minimized. The transmittance does not decrease.

[0095]

Embodiments of the present invention will be described below.

FIG. 2 is a view schematically showing one example of the liquid crystal display element of the present invention, and schematically shows an enlarged part of an array substrate and a counter substrate.

The opposite substrate 201 of the liquid crystal display element 200
Has a liquid crystal layer 203 sandwiched between it and the array substrate 202. As the counter substrate 201, a transparent conductive film 205 is formed on a transparent insulating substrate 204, and the transparent conductive film 205 is further formed.
And the alignment film 20 so as to cover the entire surface of the transparent insulating substrate 204.
6 are formed.

In the liquid crystal display device illustrated in FIG. 2, an ITO (Indium) film is formed on a transparent insulating substrate 204 made of glass.
A transparent conductive film 205 made of Tin Oxide is formed. The transparent conductive film 205 is formed as a striped electrode having a striped pattern.

In the array substrate 202, the stripe-shaped electrodes are pixel electrodes.
T (see FIG. 3).

In the liquid crystal display device having such a transparent conductive film 205 which is periodically arranged, the transparent conductive film 205 having a different refractive index and the transparent conductive film formed in a stripe shape of the liquid crystal layer 203 are provided. Although a diffraction grating is formed by the portion filled between the layers, the liquid crystal display element 200 illustrated in FIG. 2 has an optimum thickness d of the transparent conductive film 205 so as to reduce the diffraction intensity of transmitted light. Formed.

That is, assuming that the wavelength of the incident light is λ and the intensity is I ₀ ,
Assuming that the thickness of the transparent conductor film 205 is d, the refractive index is n ₁ , and the refractive index of the liquid crystal layer 203 is n ₂ , the diffraction intensity I by this diffraction grating is approximately I to sin ² (((n ₁ −n ₂ ) × d × π) / λ) × I
It becomes ₀ . Therefore, ((n ₁ −n ₂ ) × d × π) / λ
Is adjusted to be an integer.

Of course, the diffraction intensity may be reduced by appropriately selecting and using the transparent conductive film 205 or the liquid crystal layer 204 having an appropriate refractive index.

Here, since the orientation film 206 is much thinner than the transparent conductive film, the contribution to diffraction is very small.

When there is a substance other than the transparent conductive film and the liquid crystal layer that contributes to diffraction of incident light, the thickness and the refractive index of the substance may be adjusted accordingly.

That is, when the wavelength of the incident light is λ, the retardation R _i in the A region 210 on which the transparent conductive film is formed is Σ (n _i × d _i ), (i = 1, 2,..., K), and the retardation R _j in the B region 211 in which a liquid crystal layer is filled not transparent conductive film is formed sigma (n _j ×
d _j ), (j = 1, 2,..., l), more preferably, 0.8 × λ ≦ | R _i −R _j | ≦ 1.2 × λ. Can be diffracted in accordance with the wavelength of the incident light so that | R _i −R _j | = λ, that is, so that the retardation of the incident light transmitted through the diffraction grating composed of the region A and the region B is substantially equal. The refractive index or thickness of the contributing substance may be adjusted. For example, the present invention can be similarly applied to a case where retardation by an alignment film is also considered. Where 0.8 ×
In the range of λ ≦ | R _i −R _j | ≦ 1.2 × λ, a tolerance of 20% is set.

In the liquid crystal display device having the transparent conductive film provided with the thickness or the refractive index adjusted as described above, the transmittance is reduced by diffraction even when the transparent conductive film is formed in a periodic pattern. Thus, the liquid crystal display device is bright and has high contrast. Here, for example, the structure and principle of a liquid crystal display element of the type illustrated in FIG. 2 will be described in detail with reference to the drawings.

This liquid crystal display element realizes a light transmitting state by effectively forming a uniform molecular arrangement in each pixel, and obtains a refraction lens effect and a diffraction grating effect by using two or more kinds of electric field directions. This realizes a light scattering state.

Here, the refraction lens effect refers to an effect of refracting incident light by continuously changing the tilt of liquid crystal molecules in the thickness direction of the liquid crystal layer and continuously changing the refractive index of the liquid crystal layer.

[0109] Further, the diffraction grating effect, the extraordinary refractive index n _e and ordinary index n _o and the liquid crystal plane of the liquid crystal molecules,
The effect of regularly appearing alternately forms a diffraction grating in the liquid crystal layer, thereby scattering parallel light.

Light scattering due to the refraction lens effect and the diffraction grating effect can be obtained by forming a wall-shaped molecular arrangement at two or more kinds of boundaries in the direction of the electric field.

FIG. 3A is a diagram schematically showing an example of the electrode structure of one pixel portion of the liquid crystal display device. FIG.
(B) is a diagram schematically showing an example of a molecular arrangement structure when a voltage is applied.

The molecular arrangement shown in FIG. 3B is a splay arrangement, and the pretilt angles of liquid crystal molecules on the upper and lower substrate surfaces are substantially equal in the upper and lower directions. That is, a plurality of stripe-shaped electrodes 33 and 34 are arranged in pixel units on the upper and lower substrates 31 and 32, respectively, and the conductor portions 33a and 34a and the non-conductor portions 33b and 34 of each electrode are arranged.
b are shifted from each other at equal intervals by １ ／ pitch. The alignment directions of the upper and lower alignment films 35 and 36 are set to the same direction, and the liquid crystal layer 40
Are arranged in a splay arrangement. Upper and lower electrodes 3
When a voltage is applied to 3, 34, an oblique electric field e is generated.

Next, the behavior of liquid crystal molecules when an oblique electric field is applied to such a splay arrangement will be described with reference to FIGS.

FIGS. 4A to 4F show the upper and lower substrates 31,
32 and the pretilt angle α of the liquid crystal molecules on the surface of No. 32
_{In the state where 0} is the same and the liquid crystal molecules are not twisted, it shows the influence on the molecular arrangement when the electrode shapes are different.

FIGS. 4A to 4C show the states when no voltage is applied, and FIGS. 4D to 4F show the states when voltage is applied.

FIGS. 4A and 4D show a state in which the upper and lower substrates have the same electrode shape and an electric field is applied only in the liquid crystal layer thickness direction. The liquid crystal molecules are parallel to the substrate at the position d ₀ which is the middle point of the liquid crystal layer thickness d.
As shown in the figure, even when the voltage V ₀ is applied from the power supply to the electrodes 33 and 34, the position parallel to the substrate does not change.

FIG. 4B shows that the electrode 34 of the lower substrate 32 is formed in the left half in the figure, the right half is an electrodeless region, and the upper substrate 3
The other electrode 33 of one is formed in the right half in the figure, and the left half is an electrodeless region, and the mutual electrodes 33 and 34 face the electrodeless region. When the voltage V ₀ is applied, an electric field having a horizontal electric field component of the liquid crystal layer is applied due to the mutual displacement of the electrodes, and the molecules M have a steeply upward-sloping molecular arrangement as shown in FIG. . On the other hand, in FIG. 4C, the electrode 34 of the lower substrate 32 is formed in the right half in the figure, the left half is an electrodeless area, the other electrode 33 of the upper substrate 31 is formed in the left half of the figure, and the right half is formed. Is a non-electrode area, and the mutual electrodes 3
Reference numerals 3 and 34 face the electrodeless region. As shown in FIG. 4 (f), by applying a voltage V _0, for mutual displacement of the electrode, it applied electric field having a transverse electric field component in the liquid crystal layer, electric with arrow E _L component of left-side up in the illustrated Since the force lines e are generated, the directions of the liquid crystal molecules M are steeply ascending to the left. That is, the arrangement of the liquid crystal molecules at the time of applying a voltage depends on the formation of an oblique electric field having a horizontal electric field component.

In such a molecular arrangement, the tilt direction of the molecule becomes two directions as shown in the figure, depending on how the electric field is applied. This is because the arrangement of the liquid crystal molecules in the state where no voltage is applied is symmetrical between the upper half and the lower half of the liquid crystal layer. That is, the tilt direction of the liquid crystal molecules has two or more degrees of freedom.

Therefore, as exemplified in FIG. 3A, the upper electrode 33 is an electrode pattern in which a plurality of stripe-shaped conductor portions 33a are arranged at equal intervals via non-conductor portions 33b. When the pattern 34 is a pattern in which a plurality of stripe-shaped conductor portions 34a are arranged at equal intervals via a non-conductor portion 34b, when these electrodes are opposed to each other, the conductor portion 33a or 34a of one electrode is Are overlapped so as to form a gap between the substrates so as to face the non-conductive portions 34b or 33b of the electrodes.

In this case, the alignment film is subjected to a rubbing treatment so that the liquid crystal alignment directions of the upper and lower substrates are in the same direction. As a result, when no voltage is applied, the liquid crystal maintains the splay alignment state neatly. At the time of application, since the conductor portion is shifted between the upper and lower electrodes, an oblique electric field having a horizontal electric field component is generated between the electrodes, and electric lines of force e in which the inclination direction is alternately changed as shown in FIG. I do.

Since the liquid crystal molecules M rise and align along the lines of electric force, the liquid crystal alignment becomes discontinuous at the boundary between the oblique electric field rising to the right and the oblique electric field rising to the left, and the boundary in the tilt direction of the molecules (DL in the figure) ), A wall line (referred to as “wall” in this embodiment to distinguish it from disclination in a general sense that has a strong memory property and is generated when an electric field is applied). Therefore, when a voltage is applied, as shown in FIG.
L), a wall line can be generated, and a function of scattering incident light can be obtained.

As described above, in order to have two or more degrees of freedom in the tilt direction of the liquid crystal molecules, for example, the liquid crystal composition has a negative dielectric anisotropy in addition to the molecular alignment structure shown in FIG. The same effect can be obtained by using a nematic liquid crystal composition and setting the liquid crystal molecule alignment to a perfect vertical alignment in which the pretilt angle of the upper and lower substrates is 90 °. In this case, the degree of freedom of the liquid crystal molecules in the tilt-down direction is 2 degrees. That is all.

That is, when no voltage is applied to the liquid crystal molecules, the liquid crystal molecules have a substantially uniform molecular arrangement, and the liquid crystal molecules have a degree of freedom in the tilt-up direction or the tilt-down direction of 2 or more. On the other hand, if the electrode is designed so that the oblique electric field is applied in two or more opposite directions for each fine region, excellent display performance that solves the above-described problem can be obtained.

Specifically, the degree of freedom in the tilt down direction is 2
Examples of the molecular sequence include a splay sequence, a splay twist sequence, and a vertical sequence.

The electrode structure is such that a conductor portion and a non-conductor portion are formed in a minute region of the electrode, and the conductor portion of one electrode and the other portion oppose each other across the liquid crystal layer between the substrates. The electrode structure may have any structure in which the non-conductive portions of the electrodes face each other, and may include a large number of portions that significantly change the tilt direction of molecules.

By forming a large number of the above-described electrode structures in one pixel, the direction in which liquid crystal molecules occur can be finely divided, so that many wall lines can be generated in one pixel. Can cause light scattering.

An LCD based on such a principle does not require a medium other than a liquid crystal as a means for scattering light, and has no significant difference in the molecular arrangement of the liquid crystal between the light transmitting state and the light scattering state. Since it can be realized without a continuous liquid crystal molecule arrangement, it is possible to obtain a very good light scattering state with a small applied voltage and no hysteresis. In addition, the LCD can be manufactured without using a complicated manufacturing process. Further, an oblique electric field is generated in two or more directions, and the liquid crystal molecules tilt up or down according to the oblique electric field in each direction, and a wall is formed at a boundary between two or more electric field directions.
A molecular arrangement is formed, and a periodic refractive index distribution is formed. By forming a periodic refractive index distribution by liquid crystal molecules, a sufficient scattering state can be obtained by a refraction effect and a diffraction grating effect.

When scattering non-polarized light, a periodic refractive index distribution must be formed in two or more directions. Here, it is desirable that the refractive index distributions formed in each direction have the same period and the same intensity.

The formation of such a periodic refractive index distribution is as follows.
It largely depends on the angle and strength of the oblique electric field. In other words, if the angle of the oblique electric field is small, only the electric field component in the normal direction becomes too strong, an electric field close to the normal electric field is applied to the non-conductive portion of the electrode, and the liquid crystal molecules in the non-conductive portion become conductive. And the refractive index becomes uniform in the cell plane, and a periodic refractive index distribution is not formed.

On the other hand, when the angle of the oblique electric field is large, the electric field component is only a horizontal component, and no electric field is applied in the thickness direction of the liquid crystal layer in the non-conductive portion, so that the liquid crystal molecules hardly change. Therefore, it is important to optimize the angle of the oblique electric field in order to form a periodic refractive index distribution and obtain better scattering.

Here, in order to optimally apply the oblique electric field, according to the experiments of the present inventors, the tilt direction of the liquid crystal molecules has a liquid crystal molecule arrangement having two or more degrees of freedom, and the liquid crystal molecules are arranged in opposite directions. The conductive portion and the non-conductive portion are opposed to each other in at least a partial area of the pixel for each pixel between the two substrates, and the width of the narrowest portion of the non-conductive portion is S. It has been found that when the distance between the two substrates disposed opposite to each other is D, it is necessary that the relationship of S / 2D ≧ tan (π / 9) is satisfied. If the above conditions are satisfied, a liquid crystal display device having sufficient scattering characteristics can be obtained.

Further, the present inventors have conducted various experiments to
It has been found that various characteristics can be further improved by satisfying the following conditions in addition to the above conditions. This will be described below.

The light scattering effect of the diffraction grating depends on ΔNd and is expressed by the following equation.

T〜cos ² ((ΔNd · π) / λ) where T is the scattering intensity (intensity with respect to incident light).
Here, the symbol (〜) indicates that they are almost equal, ΔN is the difference between the maximum value and the minimum value of the refractive index distribution, d is the thickness of the liquid crystal layer, and λ is the wavelength of the incident light.

From this equation, the light scattering effect of the diffraction grating is ΔN
It can be seen that it has an extreme value for ΔNd depending on d.
Therefore, when the value of ΔNd is extremely large, an extreme value occurs in the electro-optical characteristics of the liquid crystal cell. This makes it difficult to express gradations using analog signals. Also, ΔNd
Is too small, a sufficient scattering effect cannot be obtained.

The present inventors have conducted various experiments in order to find a liquid crystal molecule arrangement which is more likely to cause a light scattering effect. As a result, the liquid crystal molecule arrangement shown in FIG. The effect was confirmed to be high.

In the arrangement shown in FIG. 5, 90
も の The liquid crystal molecules have a rotated arrangement, and continuously change between the liquid crystal molecules M ₁ and M ₂ . In the case of this arrangement, a refractive index distribution is formed in each of two directions, and the refractive index distributions in the two directions have the same refractive index distribution shifted by a half cycle. When the liquid crystal molecules are arranged so as to have the same periodic refractive index distribution in two directions, a high scattering effect is exhibited by the refraction effect and the diffraction grating effect.

This embodiment is characterized in that an LCD having a higher scattering effect is obtained by arranging the liquid crystal molecules as shown in FIG. 5 by using an oblique electric field. It was found that the appropriate values of the angle of the oblique electric field and ΔNd depended on the width of the conductive portion and the non-conductive portion of the electrode, the thickness of the liquid crystal layer between the substrates, and the like. I found it. These will be described below.

In the electrode structure of the first type of liquid crystal display element, one side of each pixel is a stripe and the other side is a continuous electrode. A specific example is the electrode structure shown in FIG. In FIG. 6 showing a part of one pixel, electrodes 33 forming a plurality of stripes composed of a conductor portion 33a and a non-conductor portion 33b are arranged on the upper substrate in pixel units. Conductor part 33a of this electrode 33
33a <33b
The configuration is as follows. The electrode 34 disposed on the lower substrate is a conductor portion over the entire surface. Also, the conductor portion 33
a is electrically connected to each other within one pixel.

FIGS. 7A and 7B are diagrams showing the relationship between the arrangement of the electrodes and the liquid crystal molecules. When the sectional shape in the normal direction of the liquid crystal display element is viewed, the arrangement of the electrodes is as follows. The two substrates have a cross-sectional shape in which a width EE having a conductor portion and a width RS having a non-conductor portion are alternately arranged.

When looking at the cross-sectional shape in the normal direction of the LCD, the cross-sectional shape in which the EE region and the RS region are alternately arranged may be a combination as shown in FIGS. Although the effects of the present invention can be obtained also by these electrode structures, the first type of liquid crystal display element used in this embodiment is such that the electrode of one substrate has a conductor portion for each pixel within one pixel. And the non-conductive portion, and the electrodes of the other substrate are formed of a continuous conductive portion.

According to experiments by the present inventors, in the case of the electrode structure illustrated in FIGS. 6 and 7, an electrode satisfying the relationship of tan (π / 9) ≦ RS / 2D ≦ tan (7π / 18) is satisfied. It has been found that more excellent characteristics can be obtained by adopting the structure. RS / 2D is ta
If n (π / 9) is less than n, only the electric field component in the normal direction becomes too strong, an electric field close to the normal electric field is applied to the non-conductive portion of the electrode, and the liquid crystal molecules in the non-conductive portion become In the same manner as the liquid crystal molecules, the refractive index becomes uniform in the cell plane, and a periodic refractive index distribution is not formed.

On the other hand, RS / 2D is tan (7π / 18)
It was confirmed by experiments that the electric field component was only in the horizontal direction when the ratio exceeded, and that the liquid crystal molecules in the thickness direction of the liquid crystal layer in the non-conductive portion hardly changed.

In addition, tan (π / 6) ≦ RS / 2D ≦ t
an (7π / 18), preferably tan (π /
6) ≦ RS / 2D ≦ tan (π / 3), more preferably tan (π / 4) <RS / 2D ≦ tan (7π /
18), and more preferably tan (π / 4) <
Within the range of RS / 2D ≦ tan (π / 3), a periodic refractive index distribution is formed, and a high scattering effect due to the refractive lens effect and the diffraction grating effect is obtained. Using this region, the intended refractive index distribution can be easily realized.

For example, in the case of the configuration shown in FIG. 10, by forming a portion where the molecular arrangement does not change in one pixel, a periodic refractive index distribution can be realized.

In the range of (RS / 2D)> tan (7π / 18), the required minimum oblique electric field cannot be obtained.
Since the refractive lens effect and the diffraction grating effect, which are features of this type of liquid crystal display element, are weakened, it is difficult to obtain a high scattering effect.

Regarding the width EE of the conductor portion, the following was found as a result of the experiment. For example, if EE is larger than 3D, an electric field is strongly applied to the non-conductive portion in the normal direction, and an electric field close to the normal electric field is applied, resulting in the same molecular arrangement as the liquid crystal molecules in the conductive portion, resulting in refraction. The refractive index becomes uniform in the cell plane, and no periodic refractive index distribution is formed. On the other hand, if EE is smaller than D / 2, a diagonal electric field sufficient to change the arrangement of liquid crystal molecules will not be applied.

The relationship between the width EE of the conductor portion and the width RS of the non-conductor portion is such that when the liquid crystal composition has a negative dielectric anisotropy, RS / 3 ≦ EE ≦ 1.1 × RS. 0 ≦ EE ≦ RS when the material has a positive dielectric anisotropy.

The reason will be described below with reference to FIGS.
2 will be described.

The diffraction grating effect occurs when the refractive indices n ₁ and n ₂ are alternately arranged. It is known that the ratio of n ₁ and n _{2 at} which the scattering state becomes the strongest due to the diffraction grating effect is 1: 1 (M. Born E. Wolff: Principles of Optics II, 637, Tokai University Press) , 1975). Therefore, in order to enhance the diffraction grating effect, it is only necessary that the width of the portion having a large refractive index and the width of the portion having a small refractive index be substantially the same in a plan view.

A liquid crystal display element of the first type suitable for application of the present invention has an electrode structure in which one side is a conductor portion entirely and only the other electrode is a conductor portion and a non-conductor portion. When a liquid crystal material having a negative dielectric anisotropy is sandwiched therebetween, the refractive index becomes a uniform value n ₁ when no voltage is applied, as shown in FIG. 11C. However, when voltage is applied, E
A normal electric field is applied to the portion E, and as shown in FIG.
An oblique electric field is applied to the S portion. Further, in the EE portion, the liquid crystal molecules are uniformly tilted down by the normal electric field, so that the refractive index in the direction of the stripe electrode has a uniform value n ₂ .

On the other hand, in the RS section, the liquid crystal molecules are tilted down in the direction of the oblique electric field, and the refractive index distribution becomes a continuously changed distribution. Therefore, the refractive index distribution for the component of the stripe electrode orientation is as shown in FIG. Therefore, the width Wn ₂ the refractive index at the time of Von is n ₂ is equal to EE, the width Wn ₁ in which the refractive index is an n ₁ is smaller than RS.

Here, the EE portion has a uniform refractive index, and R
Since the refractive index of the S portion changes continuously, if the widths of the EE portion and the RS portion are equal, the refractive index distribution is W
n ₁ <Wn ₂ . Therefore, Wn ₁ : Wn ₂ = 1: 1
Therefore, the width of the EE section needs to be smaller than the width of the RS section. The condition of Wn ₁ : Wn ₂ = 1: 1 is a necessary and sufficient condition for an optimum configuration, and is a range in which a practical effect can be obtained. That is, when the width of the EE portion is smaller than the width of the RS portion, the condition of Wn ₁ : Wn ₂ = 1: l can be realized by adjusting the intensity and angle of the oblique electric field.

The width of the EE portion is RS due to a manufacturing margin or the like.
Even when the width is larger than the width of the portion, the diffraction grating effect is not completely suppressed, and as a result of experiments, it has been found that there is no practical problem up to a width of 1.1 times RS. But R
If the width of S is too large, a range in which an electric field is not applied occurs, and even if an oblique electric field is adjusted, n ₂ cannot be formed in the RS region. Therefore, Wn ₁
> Wn ₂ and the diffraction grating effect cannot be obtained. As a result of the experiment, the lower limit for obtaining the diffraction grating effect is RS
It was found that / 3 ≦ EE.

In the above description, the example of the refractive index distribution for the polarization component in the stripe electrode direction has been described, but the refractive index distribution for the polarization component in the direction perpendicular to the stripe electrode direction is inverted.

When a liquid crystal composition having a positive dielectric anisotropy is used, a normal electric field is applied to the EE portion, and the refractive index becomes n ₁ for any polarized light component. The periods of the refractive index distributions of the respective polarization components are not equal. Therefore, the smaller the width of EE, the better. Therefore, in the case of a liquid crystal composition having a positive dielectric anisotropy, if 0 ≦ EE ≦ RS, the diffraction grating effect and the refraction lens effect are equal to RS and E.
It does not depend on the ratio of E. As described above, by setting the EE range to the above-mentioned value due to the difference in the dielectric anisotropy of the liquid crystal composition, an optimal oblique electric field can be applied, and a good diffraction grating effect can be obtained. .

By setting the values to satisfy the above relation,
A sufficient oblique electric field is applied to this type of liquid crystal display device.

The behavior of the liquid crystal molecules in the liquid crystal display device having such an electrode structure is shown in FIGS.
This will be described with reference to FIG.

FIG. 7A is a plan view schematically showing the behavior of liquid crystal molecules when no voltage is applied, and FIG. 7B is a cross-sectional view schematically showing the behavior of liquid crystal molecules when a voltage is applied. is there.

The upper alignment film 35 and the lower alignment film 36 are oriented so that the rubbing direction on the upper substrate surface is parallel to the electrodes, and the orientation direction is shifted by 180 ° between the upper and lower substrates. This is an alignment treatment. as a result,
The liquid crystal molecules M of the liquid crystal layer 20 have a homeotropic arrangement.

When a voltage is applied to the upper electrode 33 and the lower electrode 34, an oblique electric field e as shown in FIG. 7B is generated. The liquid crystal molecules M tilt down due to the normal component of the oblique electric field. At the same time, since an electric field of a horizontal component of the oblique electric field is applied in the thickness direction of the liquid crystal layer, the liquid crystal molecules cause a twist phenomenon in the liquid crystal layer.

That is, the liquid crystal molecules are tilted down while being twisted, and have a molecular arrangement inclined obliquely to the stripe direction. The normal electric field is applied to the EE portion, which is a conductor portion for both substrates, and only the tilt-down occurs, and the twist phenomenon does not occur. Therefore, the arrangement of the liquid crystal has a shape as shown in FIG.

The arrangement of the liquid crystal molecules shown in FIG.
It was confirmed by experiments that the molecular arrangement was close to the ideal molecular arrangement shown in FIG.

Next, a second type of liquid crystal display device suitable for the present invention will be described.

The electrode structure of the liquid crystal display device of the second type suitable for the liquid crystal display device of the present invention comprises a conductive portion and a non-conductive portion for each pixel. As a specific example,
An electrode structure shown in FIG. 13 can be given.

FIG. 13 shows one pixel portion. The electrode structure is such that electrodes 33 and 34 forming a plurality of stripes for each pixel are arranged on an upper substrate and a lower substrate, respectively.
Comparing the width of the conductor portions 33a and 34a of each electrode with the width of the non-conductor portions 33b and 34b, 33a <33
b, 34a <34b. Non-conductive part 33b, 34b
Of the conductor portions 34a and 33a
Are arranged.

The conductor portions 33a or 34a are electrically connected within one pixel.

FIGS. 14A and 14B are diagrams showing the relationship between the arrangement of electrodes and liquid crystal molecules. When the cross-sectional shape in the normal direction of the liquid crystal display element is viewed, the arrangement of the electrodes is the same as the width RE having the conductor portion on only one electrode-attached substrate with the width SS being the non-conductor portion on both substrates. It has a cross-sectional shape that is alternately arranged with the width FF having the conductor portion only on the other one of the substrates with electrodes.

The inventors of the present invention have conducted experiments to confirm that in such an electrode structure, by satisfying the relationship of tan (π / 9) ≦ SS / D ≦ tan (7π / 18), more excellent characteristics can be obtained. I found the result. SS / D is tan (π /
If it is less than 9), only the electric field component in the normal direction becomes too strong, an electric field close to the normal electric field is applied to the non-conductive portion of the electrode, and the liquid crystal molecules of the non-conductive portion become liquid crystal molecules of the conductive portion. And the periodic refractive index distribution is not formed.

On the other hand, when SS / D exceeds tan (7π / 18), it was confirmed by experiments that the electric field component was only in the horizontal direction and the liquid crystal molecules in the thickness direction of the liquid crystal layer in the non-conductive portion hardly changed. Was done.

Also, tan (π / 6) ≦ SS / D ≦ ta
n (7π / 18), preferably tan (π /
6) Within the range of ≦ SS / D ≦ tan (π / 3), more preferably tan (π / 4) <SS / D ≦ tan (7π / 1)
8), more preferably tan (π / 4) <S
Within the range of S / D ≦ tan (π / 3), a periodic refractive index distribution is formed, and a high scattering effect by the refractive lens effect and the diffraction grating effect can be obtained.

In this second type of liquid crystal display device, the region SS, which is a non-conductive portion, is always included between the regions RE and FE in both substrates because a horizontal electric field is always generated. This is to make it easier. If the width of the region SS is too large, the electric field intensity will be weakened and the liquid crystal molecules will not change. Therefore, the width of the region SS is set within the above range.

It is desirable that the width of the region SS is uniformly formed to the same width in the substrate on which the pixels are formed.
However, it is conceivable that the width of the SS varies due to a problem such as a margin generated when a liquid crystal display element is manufactured. In that case, the adjacent conductor portions F in one pixel
It is preferable to have an electrode structure which can be set to different potentials without electrically connecting E to one. With such an electrode structure, a potential difference corresponding to a shift in the width of the region SS can be generated, and variation in electric field strength can be suppressed.

In the liquid crystal display device having such a configuration,
By setting the width of the conductor portion of the upper and lower substrates to D / 2 or more and 3D or less, excellent characteristics can be obtained.

This is because, for example, if the FE or RE is 3D
Is exceeded, an electric field is strongly applied to the non-conductor portion in the normal direction, and an electric field close to the normal electric field is applied, so that a molecular row similar to the liquid crystal molecules of the conductor portion is formed, and no wall is formed.

Further, it has been confirmed by experiments that if it is smaller than D / 2, a diagonal electric field sufficient to change the arrangement of liquid crystal molecules will not be applied.

By setting the value to satisfy the above relation,
A sufficient oblique electric field is applied to the liquid crystal display device of the second type used in the liquid crystal display device of the present invention.

The behavior of the liquid crystal molecules in the liquid crystal display device having such an electrode structure is shown in FIGS.
This will be described with reference to FIG.

FIG. 14A is a plan view and a sectional view showing the behavior of liquid crystal molecules when no voltage is applied.
(B) is the top view and sectional drawing which show the behavior of the liquid crystal molecule at the time of voltage application.

The alignment directions of the upper alignment film 35 and the lower alignment film 36 are shifted by 180 °, and the liquid crystal molecules M of the liquid crystal layer 40 have a uniform arrangement.

When a voltage is applied to the upper and lower electrodes 33 and 34,
An oblique electric field e as shown in FIG. 14B is generated. Liquid crystal molecules depend on the normal component of the oblique electric field. Tilt up. At the same time, since an electric field of a horizontal component of the oblique electric field is applied in the in-plane direction of the liquid crystal layer, the liquid crystal molecules cause a twist phenomenon in the in-plane direction of the liquid crystal layer. Here, the liquid crystal molecules are initially arranged in parallel with the electrode direction, and are in a direction perpendicular to the oblique electric field.

Therefore, the direction of obtaining the twist is clockwise,
Both counterclockwise are possible. Tilt-up × (clockwise twist or counterclockwise twist) is obtained, and as a result, tilt-up in two opposite directions is obtained. That is, the degree of freedom of the tilt direction is 2. That is, the liquid crystal molecules are tilted up while being twisted, and have a molecular arrangement obliquely inclined with respect to the stripe direction.

Since the opposing portions of the conductor portions 33a and 34a are located at the center of the non-conductor portion, they are hardly affected by the oblique electric field. Therefore, the liquid crystal molecules in this portion do not change. Therefore, the arrangement of the liquid crystal is as shown in FIG.
The shape is as shown in FIG. The arrangement of the liquid crystal molecules shown in FIG. 14B is close to the ideal molecular arrangement shown in FIG. 5, and a refractive index distribution having substantially the same period and the same intensity in the two polarization directions is formed. Therefore, a high scattering effect can be obtained in non-polarized light.

As described above, in the liquid crystal display element of the type particularly suitable for the present invention, the refractive index distribution having substantially the same period and the same intensity in the two polarization directions is formed closer to the ideal molecular arrangement. The scattering effect of non-polarized light can be further enhanced as compared with the already proposed liquid crystal display element.

[0185] Incidentally, the diffraction grating effect takes place when the refractive indexes n _1, n ₂ as described above are alternately arranged, the ratio of the scattering state becomes strongest n _1, n ₂ by the diffraction grating effect 1 : 1 is known. We have:
Through various experiments, it was confirmed that the electrode configuration most likely to be n ₁ : n ₂ = 1: 1 is when the width of RE or FF is equal to the width of SS, and the allowable value of the width of RE or FF is confirmed. Was determined by experiment. As a result, it was recognized that when the width of RE or FF was less than 0.9 times or more than 1.1 times the width of SS, it was difficult to form n ₁ : n ₂ = 1: 1.

Therefore, 0.9 × SS ≦ RE ≦ 1.1
It is preferable to set x SS and 0.9 x SS? FF? 1.1 x SS.

However, since the intensity of the oblique electric field changes depending on other parameters such as the gap between the electrodes, in this case, the other parameters are optimally set to form n ₁ : n ₂ = 1: 1. You may make it.

In the LCD used in the liquid crystal display device of the present invention, the period of the refractive index distribution only needs to be such that the same period of the refractive index distribution can be obtained in the negative region. Even if the rate distribution exists within one pixel,
A diffraction grating effect and a refractive lens effect can also be obtained.

Next, the arrangement of liquid crystal molecules will be described.

The substrate of the present invention is suitable for a liquid crystal display device having a higher scattering effect by arranging the liquid crystal molecules as shown in FIG. 5 using an oblique electric field.

In this type of liquid crystal display device, the liquid crystal molecules tilt down or tilt up while causing a twist phenomenon due to an oblique electric field. Uniform arrangement,
Not limited to homeotropic alignment, liquid crystal molecules have a uniform molecular alignment in the state where no voltage is applied, and molecular alignment in which a twist phenomenon and tilt-up or tilt-down occur simultaneously when a voltage is applied, such as a spray alignment. However, the same effect can be obtained.

The molecular arrangement of this type of liquid crystal display device is as follows.
Ideally, the degree of freedom is two. It is more desirable to use a uniform arrangement and a homeotropic arrangement.

Here, in the case of the uniform arrangement, the electrode configuration is a combination of two substrates having electrodes composed of a conductive portion and a non-conductive portion, and in the case of the homeotropic arrangement, the entire surface of the electrode is a conductive substrate. It is desirable that the electrode configuration has a combination of a substrate having electrodes composed of a conductor portion and a non-conductor portion.

For example, in a uniform arrangement, when a substrate having an entire surface of a conductor and a substrate having electrodes composed of a conductor portion and a non-conductor portion is combined, the omnidirectional refractive index of the conductor portion is n ₁ . Therefore, a scattering effect can be obtained in each polarization direction, but the scattering effect is lower than that of the liquid crystal display element illustrated in FIG. 10 because the refractive index distribution in each direction is different. The same can be said for a case where two substrates having electrodes composed of a conductor portion and a non-conductor portion are combined in a homeotropic arrangement.

Therefore, when the liquid crystal molecule arrangement is a uniform arrangement, it is desirable to use the electrode configuration shown in FIG. 13 and when the liquid crystal molecule arrangement is a homeotropic arrangement, it is desirable to use the electrode configuration shown in FIG.

As described above, the light scattering effect of the diffraction grating depends on ΔNd. Here, [Delta] nd is the difference between the maximum value and the minimum value of the refractive index distribution, depending on the refractive index anisotropy Δn of the liquid crystal composition (= n _e -n _0), ideal as shown in FIG. 5 If it is a molecular sequence, Δn and ΔN are equal and n ₂
= N _e , n ₁ = n ₀ . However, a liquid crystal display element of a type suitable for the present invention twists while tilting up or down, so that ΔN tends to be smaller than the value of Δn. Therefore, it is necessary to set Δn of the liquid crystal composition to a value larger than an arbitrary ΔN.

Since the light rectilinear rate in such a liquid crystal display element is expressed by the above-mentioned equation, Tｃｏcos ² (ΔNd · π / λ), when ΔNd / λ = １ ／, the light rectilinear rate is 0
And the largest diffraction grating effect is obtained. ΔNd /
Experiments have confirmed that Δnd at which λ = 1/2 can be set within the following range by changing various Δnd and measuring electro-optical characteristics.

When light having a total visible light region of 400 nm to 700 nm is incident, the liquid crystal composition has a refractive index anisotropy Δ
The product of n and the liquid crystal layer thickness d is 350 nm ≦ Δnd ≦ 1050
It may be set within the range of nm. 350 nm
If it is smaller, a sufficient scattering effect cannot be obtained and 1050
If it is larger than nm, the electro-optical characteristics have two or more extreme values. This was confirmed by experiments.

Alternatively, the spectral characteristic bandwidth is 100 n
When monochromatic light of m or less is incident, when the central wavelength of the incident monochromatic light is λ, Δnd is (λ−50)
/ 2 nm ≦ Δnd ≦ 2 (λ + 50) nm.

In the same manner as in the range of the visible light region described above, Δnd
Is large, a plurality of extreme values occur in the electro-optical characteristics of the liquid crystal cell, and when Δnd is smaller than the above range,
Experiments have shown that the scattering effect is low.

The scattered image of this type of liquid crystal display element is a point-like scattered image in which light is diffracted at a certain angle because it utilizes the refraction effect and the diffraction grating effect. For example,
As shown in FIGS. 15A and 15B, the scattered image of the LCD configuration shown in FIG. 16 shows that the light from the light source 25 is point-scattered on a straight line in a direction orthogonal to the LCD 47 having the stripe electrodes. Can be confirmed. FIG. 15A shows a state when no voltage is applied, and FIG. 15B shows a state when a voltage is applied. FIG.
The first-order diffraction angle θ of the scattered image shown in FIG. 5B is expressed by the following equation.

Here, P is a period of the refractive index distribution formed by the liquid crystal molecules. In this type of liquid crystal display element, the first-order diffraction angle θ needs to be 1 deg or more. If it is 1 deg or less, the distance between the 0th-order diffracted light and the 1st-order diffracted light becomes too short,
The diffracted lights overlap, and a sufficient scattering effect cannot be obtained. Also, the scattering angle increases as the first-order diffraction angle increases. To increase the diffraction angle, the period of the refractive index distribution may be reduced.

However, the present inventors have confirmed that the period of the refractive index distribution is substantially equal to the sum of the non-conductive portion and the conductive portion of the electrode, and the width of the non-conductive portion and the width of the conductive portion has been confirmed. Has various restrictions as described above, and cannot be narrowed much.

The present inventors set the first-order diffraction angle to 10 deg.
That is, the sum of the widths of the non-conductive portion and the conductive portion is 2.5 μm (λ
= 440 nm) was the limit. Also, 1
When the next diffraction angle is 1 deg, the sum of the widths of the non-conductive portion and the conductive portion is 36 μm (λ = 640 nm).

Therefore, in the substrate with electrodes, a first type of liquid crystal display in which a substrate having an electrode composed of one conductor portion and a non-conductor portion is opposed to a substrate having the entire surface of the other electrode being a conductor. In the case of an element, 2.5 μm ≦ EE + RS ≦
It is advisable to set it within the range of 36 μm.

In the case of a liquid crystal display device of the second type in which two substrates having electrodes composed of a conductor portion and a non-conductor portion are combined, 2.5 μm ≦ RE + SS ≦ 36 μm and 2.5 μm ≦ FE + SS ≦ It may be set within the range of 36 μm.

By setting such various conditions, in the liquid crystal display element of the type suitable for the present invention, it is possible to obtain a high scattering effect with a large scattering angle due to the refractive lens effect and the diffraction grating effect. .

Also, a liquid crystal display element of a type suitable for the present invention is manufactured with a twist angle of 0 deg, and is combined between two orthogonal polarizing plates such that the rubbing directions are parallel to the absorption axis of one of the polarizing plates. Thus, even when a scattering light source is used, a transmission type display can be obtained.

In this case, an optical mode utilizing the birefringence effect is provided, and the above-described transmittance is reduced. However, since the light transmission state is realized by the light scattering state of the liquid crystal layer, the effect that the viewing angle dependency is small is obtained. In particular, since a phenomenon that the display is inverted when a gradation display is performed does not occur, a display characteristic superior to a conventional TN-LCD or the like can be obtained as a direct-view display.

Since the liquid crystal display device of the present invention has a function of scattering light, the light source for irradiating the liquid crystal display device is preferably parallel light having an angle perpendicular to the plane of the liquid crystal display device. . Specifically, it was confirmed by an experiment that there was no problem as a light source if light having an angle of less than 10 deg with respect to the normal direction of the liquid crystal display element plane could be incident. As means for collimating light, for example, a schlieren optical system or the like can be used.

FIG. 16 is a configuration diagram of a generally used schlieren optical device. The Schlieren optical device includes a parallel light source 45 composed of a reflecting mirror 58 and a lamp 59.
And a liquid crystal display element 47, a condenser lens 48, an aperture 49 for removing unnecessary light, and a projection lens 50 for enlarging and projecting a display image.
It comprises a screen 51.

Next, the operation will be described. The illumination light beam emitted as a parallel light beam from the light source is applied to the liquid crystal display element 47. As the lamp of the light source 59, for example, a discharge lamp such as a metal halide lamp or a xenon lamp, or a halogen lamp is used in combination with the reflecting mirror 58. An image is displayed on the surface of the liquid crystal display element 47, and a light beam incident on the surface is transmitted or scattered according to the density of the displayed image. The light beam L ₀ emitted perpendicularly to the display surface of the liquid crystal display element 47 is condensed on the stop by the condenser lens 48, passes through the stop 49, and then enters the projection lens 50. Scattered by the liquid crystal display device 48, the light beam L _e transmitted through the condensing lens 48 is blocked by the stop 49 can not be incident on the projection lens 50. That is, the diaphragm 49 functions to selectively block unnecessary light (scattered light) and selectively transmit only a light flux emitted almost perpendicularly from the liquid crystal display element 47 to the projection lens, thereby improving the contrast. The light beam transmitted through the projection lens 50 is enlarged and formed on the screen 51.

A projection type liquid crystal display device using a first type or a second type of liquid crystal display element suitable for the present invention will be described with reference to FIGS.

In the projection type liquid crystal display device shown in FIG. 17, the light from the light source 45 becomes almost parallel light by the schlieren lens 46 and is projected on the screen 51 by the projection lens 50 through the liquid crystal display element 47 and the condenser lens 48 of the present invention. It is a structure that is performed. An aperture 49 is provided at the focal point of the condensing lens 48 to project only the straight light out of the parallel light incident on the liquid crystal display element, and the light scattered by the liquid crystal display element 47 is blocked. I have.

The projection type liquid crystal display device shown in FIG. 18 uses two or more liquid crystal display elements of the present invention, and includes a white light source 57 having the same function as the light source used in FIG. And disperse it to an arbitrary wavelength. Examples of the means for separating light include a dichroic mirror and a color filter. The split light is incident on the liquid crystal display elements 47a, 47b, and 47c, respectively.

With this configuration, it is possible to control the optical path for each wavelength. Therefore, color display can be realized.

When a liquid crystal display element suitable for the present invention is used for matrix display, there arises a problem that the overall transmittance is reduced depending on the pixel area of the modulation section, that is, the value of the opening. In particular, a liquid crystal display element used for a projection type liquid crystal display device requires simplification of the element in terms of configuration. In the case of a simple matrix, the proportion of the non-modulation portion including the insulating region increases, and in the case of the switching element, the proportion of the non-modulation portion including the switching element and the wiring region increases. In order to ensure contrast, it is desirable to shield these non-modulation portions from light. Therefore, these liquid crystal display elements have practically low transmittance.

Such a problem can be solved by providing a layer having the same function as an optically convex lens in the light transmission path of the liquid crystal display element. Such examples are shown in FIGS. In FIG. 19, a layer 60 having the same function as an optically convex lens is provided between substrates on the rear surface of the outer surface on the incident light side, and light traveling to the light shielding layer is condensed on the modulation section in the aperture of the pixel. In the liquid crystal display element suitable for the present invention, it is desirable that light incident on and passing through the liquid crystal layer take an optical path parallel to the normal direction of the substrate. Therefore, FIG.
As shown in (1), when the traveling direction of the light condensed on the opening is substantially the same as the normal direction of the substrate, it is possible to improve the transmittance and maintain the contrast. In order to obtain such an effect, as shown in FIG. 20, an optical element is provided between the electrode of the incident light side substrate of the liquid crystal display element suitable for the present invention and the layer having the same function as the above-mentioned optically convex lens. May be provided with a layer 60 having the same function as a convex lens or a concave lens. The angle between the light transmitted through the layer having the same function as the optically convex lens and the layer having the same function as the optically convex lens or the concave lens with respect to the normal direction in the surface of the liquid crystal display element is equal to the angle of the incident light. If the function equivalent to the above-mentioned optically convex lens is controlled so as to be 0.9 to 1.1 times the angle formed with the normal direction in the plane of the display element, the light incident on the liquid crystal layer has a parallelism. The contrast can be maintained along with the transmittance.

Next, an example in which the present invention is applied to a liquid crystal display element of a type suitable for the present invention described above will be described in detail.

FIG. 21 is an enlarged perspective view schematically showing a pair of striped electrodes formed on the counter substrate and the array substrate of the liquid crystal display device of the present invention.

FIG. 22A is a plan view and a cross-sectional view of the liquid crystal display element 2100 of FIG. 21 in which electrodes are applied when no voltage is applied, and FIG. 22B is a diagram in which electrodes are applied when voltage is applied. FIG. 22 is a plan view and a cross-sectional view of the liquid crystal display element 2100 of FIG. 21.

This liquid crystal display element 2100 is formed by
The opposing substrate 2101 in which the liquid crystal layer 2120 is sandwiched between the substrate 101 and the array substrate 2102 has a plurality of stripe-like common electrodes made of, for example, ITO on the entire side surface of the transparent insulating substrate 2111 such as glass, which sandwiches the liquid crystal layer. 2113 is formed, and an upper alignment film of polyimide (AL-3046, manufactured by Japan Synthetic Rubber) 211 is formed thereon.
5 are stacked.

In the array substrate 2102, a TFT, a gate line, and a signal line are formed on a transparent insulating substrate 2112 made of, for example, glass, and a stripe-shaped pixel electrode 2114 made of, for example, ITO is formed in connection with the TFT. I have. Then, from above, a polyimide lower alignment film (AL-
3046, manufactured by Japan Synthetic Rubber Co.) 2116. The stripe-shaped pixel electrode 2114 has a size of 96 μm.
It is m × 96 μm, and is arranged in a mosaic in pixel units. The pretilt angle of the upper and lower alignment films 2115 and 2116 is 3
゜.

The stripe-shaped common electrode 2113 has a width of 16 μm.
m to have a plurality of slit areas 2113b
This is a pattern in which μm transparent conductive films 2113a are arranged in stripes at a pitch of 24 μm, and four stripes are formed within a width of 96 μm per pixel.

Similarly, the striped pixel electrode 2114 facing the striped common electrode 2113 has a pattern having a transparent conductive film 2114a having a width of 8 μm and a plurality of slits 2114b having a width of 16 μm.
Book stripes 2114a are formed.

The stripe portions of these stripe-shaped electrodes are arranged so as to be shifted from each other by 12 μm in a state where the array substrate and the counter substrate are opposed to each other. 21
14a is a slit portion 2114b or 2 between electrode stripes formed on the other substrate.
It is provided so as to face the central portion of 113b.

The pixel electrodes 2114 are connected to the TFT switching elements 2119, respectively, and are connected to the gate lines 212.
The voltage applied to the signal line 2124 is applied to the liquid crystal according to the voltage applied from 3.

The orientation directions F of the orientation films 2115 and 2116,
R is set so as to be parallel to the stripe portion of the stripe-shaped electrode and to have a direction different by 180 °.

The gap between the array substrate and the counter substrate is 5 μm.
m and a liquid crystal cell is formed. A nematic liquid crystal having a negative dielectric anisotropy (E320, manufactured by Merck Japan) is filled between these substrates to form a liquid crystal layer 2120. This liquid crystal has a birefringence (Δn) of 0.143 and a Δnd of 715 nm.

Here, the refractive index of the transparent conductive film forming the stripe-shaped electrode was 2.0, and the film thickness was 1.1 μm. The refractive index in the thickness direction of the slit-shaped region formed between the stripes is 1.5, which is the same value as the refractive index of the alignment film and the liquid crystal layer.

A voltage was applied to the thus obtained liquid crystal display device of the present invention via the TFT 2119, and the electro-optical characteristics (transmittance-applied voltage curve) were measured.

The application of a voltage generates an electric field having a horizontal electric field component between the electrodes, and changes the direction of the horizontal electric field component within a minute range of one pixel. Therefore, the liquid crystal molecules M of the liquid crystal layer 2120 respond to the electric field. Change the array. Therefore, a refractive index distribution is formed.

In order to obtain a transmittance-applied voltage curve, He-Ne laser light (λ = 550 nm) was incident on the liquid crystal display element, and the transmittance was measured. FIG. 23 is a diagram showing the measurement results and a comparative example.

The spot diameter of the laser light was 1 mm, and the transmitted laser light was detected by a photodiode provided at a distance of 20 cm from the liquid crystal display element. The applied voltage is gradually increased from 0 V to 5 V, and then 5 V
From 0 to 0V.

When no voltage was applied, the light transmittance of the pixel region was 85%, which was a bright transmittance characteristic. At a voltage of 2.8 V, a minimum transmittance of 0.4% and good scattering characteristics were obtained. No hysteresis was observed in the electro-optical characteristics. The response speed was measured with the applied voltages set to 2.8 V and 0 V.
An extremely fast response speed of 0 msec and falling of 20 msec was obtained.

For comparison, the thickness of the transparent conductive film of the striped electrode of the liquid crystal display element illustrated in FIG.
A liquid crystal display device similar to that used in the measurement of FIG.

The transmittance-applied voltage characteristic of the comparative example was measured by the same method. As a result, the maximum transmittance was about 5% lower than that of the liquid crystal display device of the present invention.

This is because when the thickness of the transparent conductive film is 3000 angstroms, ΔR does not become an integral multiple of 550 nm, and the transmittance is reduced due to diffraction by the striped electrodes.

FIG. 24 is a diagram schematically showing one pixel portion of another example of the liquid crystal display device of the present invention.

The liquid crystal display element 2400 illustrated in FIG.
Is a red transmission area 2402 through which red, green, and blue colors are transmitted in one pixel area using a color filter 2401.
a, green transmission area 2402b, blue transmission area 2402c
Are formed on the side surfaces of the array substrate 2403 and the counter substrate 2404 sandwiching the liquid crystal layer, in the regions corresponding to the transmission regions of the respective colors, by the stripe-shaped electrodes 2 made of a transparent conductive film.
405a, 2405b and 2405c were formed. The stripe-shaped electrodes 2405 provided in the respective color transmission regions were formed by optimizing according to the wavelength λ _i of light passing through each region. That is, in the red transmission region 2402a, the thickness of the stripe-shaped electrode is set to 1.28 μm,
At 402b, the thickness of the stripe-shaped electrode is reduced to 1.1 μm.
In the blue transmission region 2402c, the thickness of the stripe-shaped electrode was set to 0.88 μm.

Here, an alignment film, not shown, is formed on the array substrate 2403 and the counter substrate 2404 from above the respective stripe-shaped electrodes 2405.

Accordingly, in each color transmission area 2402,
The diffraction intensity of the transmitted light by the striped electrodes is minimized, and the liquid crystal display device is bright and has high contrast.

Parallel light was incident on the liquid crystal display element 2400 thus obtained, and only the straight light was enlarged and projected. As a result, a bright and uniform display was obtained.

The same applies to the case where color display is performed using a microlens array instead of a color filter.

Instead of RGB, a region where each color of cyan, magenta and yellow is transmitted is formed in one pixel region, and a striped electrode made of a transparent conductive film is formed in a transmission region of each color. You may.

In this case, the stripe-shaped electrode provided in each color transmission region has a wavelength λ of the strongest light transmitted through the film thickness.
_It may be formed by optimizing according to _i .

For example, the thickness of the stripe-shaped electrode is set to 0.88 μm in the cyan transmission region, the thickness of the stripe-shaped electrode is set to 1.1 μm in the magenta transmission region, and the thickness of the stripe-shaped electrode is set in the yellow transmission region. 0.88μ
m may be set. FIG. 25 is a diagram illustrating a projection type color liquid crystal display device manufactured using a liquid crystal display element 2400 similar to the liquid crystal display element illustrated in FIG.

The light source light from the metal halide 45 is converted into parallel light by the schlieren lens 46, and the stripe-shaped electrode made of a transparent conductive film illustrated in FIG. 24 is formed by optimizing according to the wavelength of transmitted light. The projection lens unit 5 passes through the liquid crystal display element 2400 and the condenser lens 48.
0 is projected on the screen 51.

Drive device 52 and video signal output device 5
The image input to the liquid crystal display element 2400 by 3 is enlarged and displayed on the screen 51.

The liquid crystal display device of the present invention is capable of controlling the straight traveling or scattering of the parallel light path by an electric field. Therefore, an arbitrary image can be displayed on the screen 51 by using the schlieren optical system as illustrated in FIG.

In this example, in order to project only the straight light out of the parallel light incident on the liquid crystal display element 2400, an aperture 49 having a diameter of 5 mm was provided at the focal position of the condenser lens 48, and the light was scattered by the liquid crystal display element 47. The light is blocked.

When a video signal was projected about 30 times using the projection type liquid crystal display device having such a configuration, a contrast of 400: 1 was obtained. In addition, it was extremely bright and had high display quality.

FIG. 26 is a diagram showing a projection type color liquid crystal display device formed by employing three liquid crystal display elements 2100 similar to the liquid crystal display element exemplified in FIG.

The three liquid crystal display elements 2100a and 2100
b and 2100c are configured to transmit each color of RGB, and the thickness of the striped electrode is 1.28 μm in the red transmission liquid crystal display element 2100a, 1.1 μm in the green transmission liquid crystal display element 2100b, and blue. The transmission liquid crystal display element 2100c is formed to be 0.88 μm, which is optimized so as to reduce the diffraction intensity.

In this example, a white light source 57 including three wavelengths of RGB is used as a light source, and this is separated into red, green, and blue wavelengths using dichroic mirrors 54 and 55 and a total reflection mirror 56, respectively. Then, the light is incident on three liquid crystal display elements 2100a, 2100b, and 2100c.

By adopting such a configuration, it is possible to control the optical path for each wavelength, and a color display can be realized. The dichroic mirror 54 transmits red wavelengths and totally reflects green and blue wavelengths, and the dichroic mirror 55 transmits green wavelengths and totally reflects blue and red wavelengths.

Using this projection type liquid crystal display device, a full-color video signal image was projected about 30 times to obtain a contrast ratio of 200: 1. In addition, an extremely bright high-quality display was obtained.

FIGS. 27 to 34 are diagrams schematically showing examples of slit-shaped electrodes which can be used in the liquid crystal display device, the projection type liquid crystal display device, and the substrate of the present invention. For example, the present invention may be applied to the electrode structures illustrated in FIGS. 27 to 34 in addition to the slit-shaped electrodes illustrated in FIGS. 3, 6, 13, and 21.

[0259]

As described above, in the liquid crystal display device of the present invention, the diffraction effect produced by the stripe-shaped electrode formed of the transparent conductive film having the periodic pattern formed on the substrate sandwiching the liquid crystal layer is reduced by the region. Can be reduced by optimizing the refractive index or the thickness of the substance present in accordance with the wavelength of transmitted light. Therefore, a reduction in light transmittance due to diffraction is effectively suppressed, and a bright and high-contrast liquid crystal display device is obtained.

In the projection type liquid crystal display device of the present invention, the diffraction effect of transmitted light generated by the stripe-shaped electrode formed of a transparent conductive film having a periodic pattern formed on the substrate sandwiching the liquid crystal layer is applied to the region. By employing a liquid crystal display element formed by optimizing the refractive index or thickness of an existing substance in accordance with the wavelength of transmitted light, the thickness can be reduced. Therefore, a reduction in light transmittance due to diffraction is effectively suppressed, and a bright and high-contrast projection type liquid crystal display device is obtained.

Further, the substrate of the present invention can provide a diffraction effect caused by a stripe-shaped electrode formed of a transparent conductive film having a periodic pattern formed on a substrate sandwiching a liquid crystal layer, by using a refractive index of a substance existing in the region or This is a substrate whose thickness can be reduced by optimizing the thickness in accordance with the wavelength of transmitted light.

[Brief description of the drawings]

FIG. 1 is a diagram schematically showing a partial cross section of a counter substrate of a liquid crystal display element of the present invention.

FIG. 2 is a diagram schematically showing a partial cross section of a liquid crystal display device of the present invention.

FIG. 3 is a diagram illustrating a previously proposed liquid crystal display device.
(A) is a perspective view showing a stripe-shaped electrode facing each other across a liquid crystal, and (b) is a cross-sectional view of the liquid crystal display element when voltage is applied.

FIGS. 4A to 4C are diagrams schematically showing the behavior of liquid crystal molecules in a splay arrangement, wherein FIGS.
(D)-(f) is a figure which shows the time at the time of voltage application.

FIG. 5 is a diagram schematically showing an ideal liquid crystal molecule arrangement.

FIG. 6 is a perspective view showing stripe electrodes facing each other across a liquid crystal of a first type of liquid crystal display element suitable for the present invention.

7A and 7B are diagrams schematically illustrating a first type of liquid crystal display device suitable for the present invention, wherein FIG. 7A is a diagram illustrating a plane and a cross section of the liquid crystal display device when no voltage is applied, and FIG. 3A and 3B are a plan view and a cross-sectional view of a liquid crystal display element when a voltage is applied.

FIG. 8 is a diagram schematically showing a cross section of a liquid crystal display element in which EE regions and RS regions are alternately arranged.

FIG. 9 is a diagram schematically showing a cross section of another example of a liquid crystal display element in which EE regions and RS regions are alternately arranged.

FIG. 10 is a diagram schematically showing a liquid crystal molecular arrangement.

FIG. 11 is a diagram schematically showing a relationship between an EE region and an RS region when no voltage is applied.

FIG. 12 is a diagram schematically showing a relationship between an EE region and an RS region when a voltage is applied.

FIG. 13 is a perspective view showing stripe electrodes facing each other across a liquid crystal of a second type of liquid crystal display element suitable for the present invention.

14A and 14B are diagrams schematically illustrating a second type of liquid crystal display device suitable for the present invention, wherein FIG. 14A is a diagram illustrating a plane and a cross section of the liquid crystal display device when no voltage is applied, and FIG. 3A and 3B are a plan view and a cross-sectional view of a liquid crystal display element when a voltage is applied.

FIG. 15 is a view schematically showing a scattered image of a second type liquid crystal display element.

FIG. 16 is a diagram illustrating a configuration of a schlieren optical device.

FIG. 17 is a diagram showing a configuration of a projection type liquid crystal display device suitable for the present invention.

FIG. 18 is a diagram showing a configuration of another projection type liquid crystal display device suitable for the present invention.

FIG. 19 shows an arrangement of a liquid crystal display element and a micro lens.
Sectional drawing which shows an example schematically.

FIG. 20 is a sectional view schematically showing another example of the arrangement of the liquid crystal display element and the microlenses.

FIG. 21 is a perspective view showing stripe-shaped electrodes which are arranged to face each other across a liquid crystal layer of the liquid crystal display element of the present invention.

22A is a diagram illustrating a plane and a cross section of a liquid crystal display element when no voltage is applied, and FIG. 22B is a diagram illustrating a plane and a cross section of the liquid crystal display element when a voltage is applied.

FIG. 23 is a diagram showing the relationship between the transmittance and the applied voltage of the liquid crystal display device of the present invention and the conventional liquid crystal display device.

FIG. 24 is a diagram schematically showing another liquid crystal display element of the present invention.

FIG. 25 is a diagram showing a configuration of an example of a projection type liquid crystal display device of the present invention.

FIG. 26 is a diagram showing a configuration of another example of the projection type liquid crystal display device of the present invention.

FIG. 27 is a view schematically showing another example of a striped electrode.

FIG. 28 is a view schematically showing another example of a striped electrode.

FIG. 29 is a view schematically showing another example of a striped electrode.

FIG. 30 is a view schematically showing another example of a striped electrode.

FIG. 31 is a view schematically showing another example of a striped electrode.

FIG. 32 is a view schematically showing another example of a striped electrode.

FIG. 33 is a view schematically showing another example of a striped electrode.

FIG. 34 is a view schematically showing another example of a striped electrode.

FIG. 35 is a diagram schematically showing one example of a liquid crystal display element in which a transparent insulating substance is filled in a slit region of a striped electrode with a transparent insulating substance.

[Explanation of symbols]

31 upper substrate, 32 lower substrate, 33 upper electrode, 3
3a Upper electrode conductive portion 33b Upper electrode non-conductive portion, 34 Lower electrode, 34a
... lower electrode conductive part 34b ... lower electrode non-conductive part, 35 ... upper alignment film, 36 ...
... Lower alignment film 39 Switching element 40 Liquid crystal layer 43
Gate line 44 ... Signal line 45 ... Light source 46 ... Schlieren lens 47 ... Liquid crystal display element 48 ... Condenser lens 49 ...
Aperture 50 Projection lens 51 Screen 52 Driving device 53 Video signal output device 54 55 Dichroic mirror 56 Total reflection mirror 57 White light source 100 Liquid crystal display device , 101... Counter substrate, 102
... a liquid crystal layer 103 ... a transparent insulating substrate, 104 ... a transparent conductive film,
Reference numeral 105: Alignment film 106: A region, 107: B region 200: Liquid crystal display element, 201: Counter substrate, 202
... Array substrate 203 Liquid crystal layer 204 Transparent insulating substrate 205
...... transparent conductive film 206 ... alignment film 2100 ... liquid crystal display element, 2101 ... counter substrate, 2
102 Array substrate 2111, 2112 Transparent insulating substrate, 2113 Striped common electrode 2113b Slit region, 2114 Striped pixel electrode 2115, 2116 Alignment film, 2119 Switching element 2120 Liquid crystal Layer, 2123 ... Gate line, 2124
... Signal line 2400 ... Liquid crystal display element, color filter ... 240
1 2402a red transmission region, 2402b green transmission region 2402c blue transmission region, 2403 array substrate 2405 stripe electrode 3501 transparent insulating substrate, 3502 stripe electrode 3503 transparent Insulating substance, 3504: Alignment film

Claims (28)

[Claims] 1. A second substrate, which is disposed to face a liquid crystal layer and a first substrate while maintaining a distance D therebetween, and forms a plurality of pixel regions with the liquid crystal layer interposed between the first substrate and the first substrate. A conductive film having a refractive index of n and a thickness of d formed in the pixel region of the first or second substrate, and having a minimum width of 2Dtan.
A stripe-shaped electrode having slits that are periodically arranged and larger than (π / 9), wherein the stripe-shaped electrode is a first electrode that is formed when light passes through the conductive film. And a second phase difference R generated when the light passes through the medium existing between the stripes of the stripe-shaped electrode, so that the difference between the phase difference is an integral multiple of the wavelength of the light. Alternatively, a liquid crystal display device characterized in that the thickness d is adjusted. 2. A second substrate, which is arranged to face a liquid crystal layer and a first substrate while maintaining a distance D therebetween, and forms a plurality of pixel regions with the liquid crystal layer interposed between the first substrate and the second substrate. A conductive film having a refractive index of n and a thickness of d formed in the pixel region of the first or second substrate, and having a minimum width of 2Dtan.
A stripe-shaped electrode having slits that are periodically arranged and larger than (π / 9), wherein the stripe-shaped electrode is a first electrode that is formed when light passes through the conductive film. a phase difference R _i of the difference between the second phase difference R _j generated when the medium the light that exists between the stripes of the first electrode is transmitted _{is, 440nm ≦ | R i -R j} | ≦ 640nm A liquid crystal display device characterized in that the refractive index n or the thickness d is adjusted so that 3. A second substrate, which is disposed opposite to the liquid crystal layer while maintaining a distance D from the first substrate, and forms a plurality of pixel regions with the liquid crystal layer interposed between the first substrate and the liquid crystal layer. A conductive film having a refractive index of n and a thickness of d formed in the pixel region of the first or second substrate, and having a minimum width of 2Dtan.
A stripe-shaped electrode having slits that are periodically arranged and larger than (π / 9), wherein the stripe-shaped electrode is a first electrode that is formed when light passes through the conductive film. a phase difference R _i of the difference between the second phase difference R _j that occurs when the medium lying between the stripes of the stripe-shaped electrode and the light passes is, when the wavelength of transmitted light was set to lambda _i , 0.8 × λ _i ≦ | R _i −R _j | ≦ 1.2 × λ _i , the refractive index n according to the wavelength λ _i of the transmitted light.
Alternatively, a liquid crystal display device characterized in that the thickness d is adjusted. 4. A second substrate, which is disposed to face a liquid crystal layer and a first substrate while maintaining an interval D, and forms a plurality of pixel regions with the liquid crystal layer interposed between the first substrate and the liquid crystal layer. A conductive film having a refractive index of n and a thickness of d formed in the pixel region of the first or second substrate, and having a minimum width of 2Dtan.
A stripe-shaped electrode having slits that are periodically arranged and larger than (π / 9), wherein the stripe-shaped electrode is a first electrode that is formed when light passes through the conductive film. a phase difference R _i of the difference between the second phase difference R _j that occurs when the medium lying between the stripes of the stripe-shaped electrode and the light passes is, when the wavelength of transmitted light was set to lambda _i , 0.8 × λ _i ≦ | R _i −R _j | ≦ 1.2 × λ _i , the refractive index n according to the wavelength λ _i of the transmitted light.
Alternatively, a liquid crystal display device characterized in that the thickness d is adjusted. 5. A second substrate for sandwiching the liquid crystal layer between a liquid crystal layer and a first substrate, and a side surface of the first substrate or the second substrate for sandwiching the liquid crystal layer, wherein a conductive material is provided. A first phase difference generated when light passes through the conductor film, and a second phase difference generated when the light passes through the liquid crystal layer by substantially the same thickness as the conductor film. A liquid crystal display device comprising: a plurality of stripe-shaped electrodes formed by adjusting the refractive index or the film thickness so that the difference from the phase difference is an integral multiple of the wavelength of transmitted light. 6. A second substrate sandwiching the liquid crystal layer between a liquid crystal layer and a first substrate, and a side surface of the first substrate or the second substrate sandwiching the liquid crystal layer between the first substrate and the second substrate. A first phase difference generated when light passes through the conductor film, comprising a conductor film having a ratio n and a thickness d;
The difference from the second phase difference R generated when the light transmits through the liquid crystal layer by substantially the same thickness as the conductive film is 440 nm ≦ | (nxd) −R | ≦ 640 nm. And a striped electrode formed by adjusting the refractive index n or the thickness d as described above. 7. A second substrate sandwiching the liquid crystal layer between a liquid crystal layer and a first substrate, and a side surface of the first substrate or the second substrate sandwiching the liquid crystal layer has a refraction. A first phase difference generated when light passes through the conductor film, comprising a conductor film having a ratio n and a thickness d;
When the light is a difference between the second phase difference R caused when transmitting only the conductive film substantially the same thickness as the liquid crystal layer, where the wavelength of the light and lambda _i, 0.8 × a ≦ 1.2 × striped electrode formed by adjusting in accordance with the refractive index n or the thickness d such that the lambda _i to the wavelength lambda _i of the light _{| λ i ≦ | (n ×} d) -R A liquid crystal display device comprising: 8. A pixel region comprising a liquid crystal layer, a first region through which first light having a first center wavelength is transmitted, and a second region through which second light having a second center wavelength is transmitted. And a first substrate having the liquid crystal layer interposed between the first substrate and the first substrate.
A second substrate having the pixel region corresponding to the first substrate and a first substrate and a second substrate having a refractive index n on a side surface of the first substrate or the second substrate on which a liquid crystal layer is sandwiched. ,
A first phase difference generated when light passes through the conductor film, and the light passes through the liquid crystal layer by substantially the same thickness as the conductor film, which is made of a conductor film having a thickness d. When the center wavelength of transmitted light is λ _i , the difference between the second phase difference R and the generated second phase difference R is 0.8 × λ _i ≦ | (n × d) −R | ≦ 1.2 × λ _i And a stripe-shaped electrode formed by adjusting the refractive index n or the thickness d according to the wavelength λ _i of light passing through the first and second regions so that Liquid crystal display element. 9. A second substrate that forms a plurality of pixel regions by sandwiching the liquid crystal layer between a liquid crystal layer and a first substrate; and each of the pixel regions of the first or second substrate. A plurality of filters formed so as to respectively transmit a plurality of lights having different center wavelengths; and a region corresponding to each of the filters on a side surface of the first substrate or the second substrate that sandwiches the liquid crystal layer. n,
A conductive film having a thickness of d, and a first phase difference generated when light passes through the conductive film and a first phase difference generated when light passes through the liquid crystal layer by substantially the same thickness as the conductive film. difference between the phase difference R of 2, when the wavelength of transmitted light was set to _{λ i, 0.8 × λ i ≦} | (n × d) -R | transmissive such that ≦ 1.2 × λ _i A striped electrode formed by adjusting the refractive index n or the thickness d according to the wavelength of the light to be emitted according to λ _i . 10. A liquid crystal layer, a second substrate interposing the liquid crystal layer between the first substrate, and a first substrate or a second substrate having a side surface interposing the liquid crystal layer periodically. consisting of a first medium and the second medium are arranged, the first and the phase difference R _i that occurs when light passes through the first medium, occurs when the light passes through the second medium A diffraction grating formed by adjusting the refractive index or the thickness of the first medium or the second medium so that the difference from the second phase difference _Rj is an integral multiple of the wavelength of the light. A liquid crystal display device characterized by the above-mentioned. 11. A second substrate that sandwiches the liquid crystal layer between a liquid crystal layer and a first substrate, and a second substrate that periodically sandwiches a side surface of the first or second substrate that sandwiches the liquid crystal layer. consisting of a first medium and the second medium are arranged, the first and the phase difference R _i that occurs when light passes through the first medium, occurs when the light passes through the second medium the difference between the second phase difference R _{j is, 440nm ≦ | R i -R j} | ≦ 640nm become as first medium or grating which is formed by adjusting the refractive index or thickness of the second medium A liquid crystal display device comprising: 12. A liquid crystal layer, a second substrate sandwiching the liquid crystal layer between the first substrate, and a first substrate or a side surface of the second substrate sandwiching the liquid crystal layer periodically. consisting of a first medium and the second medium are arranged, the first and the phase difference R _i that occurs when light passes through the first medium, occurs when the light passes through the second medium the difference between the second phase difference R _j is, when the wavelength of the light was _{λ i, 0.8 × λ i ≦} | R i -R j | such that ≦ 1.2 × λ _i, wherein A liquid crystal display device comprising: a diffraction grating formed by adjusting a refractive index or a thickness of a first medium or a second medium according to a wavelength λ _i of light. 13. A pixel region comprising a liquid crystal layer, a first region through which first light having a first central wavelength passes, and a second region through which second light having a second central wavelength passes. And a first substrate having the liquid crystal layer interposed between the first substrate and the first substrate.
A second substrate having the pixel region corresponding to the first substrate; and a first substrate or a second substrate, which is periodically arranged in a first region and a second region on a side surface sandwiching the liquid crystal layer. consisting of a first medium and the second medium, the first and the phase difference R _i that occurs when light passes through the first medium, the light of the second occurring when passing through the second medium difference between the phase difference R _j is, when the wavelength of the light was _{λ i, 0.8 × λ i ≦} | R i -R j | wavelength of the such that ≦ 1.2 × λ _i light lambda A liquid crystal display device comprising a diffraction grating formed by adjusting the refractive index or thickness of the first medium or the second medium according to _i . 14. The liquid crystal display device according to claim 1, wherein one of the first medium and the second medium is a conductor. 15. The first medium is a transparent conductor film and the second medium
The liquid crystal display device according to claim 1, wherein the medium is liquid crystal constituting the liquid crystal layer. 16. The liquid crystal display device according to claim 1, wherein the maximum width of the stripe and the maximum width of the slit of the stripe electrode are 50 μm or less. 17. The method according to claim 17, wherein a stripe region of the stripe-shaped electrode formed on the first substrate is formed to face a slit region of the stripe-shaped electrode formed on the second substrate. A liquid crystal display device according to claim 1. 18. A light source, (b) a liquid crystal layer, a second substrate sandwiching the liquid crystal layer between first substrates, and the first substrate or the second substrate. A first phase difference generated when light passes through the conductive film, the first phase difference being made of a conductive film on the side surface sandwiching the liquid crystal layer, and the light having the liquid crystal layer having substantially the same thickness as the conductive film; A liquid crystal display element having a plurality of stripe-shaped electrodes formed by adjusting the refractive index or the film thickness so that the difference from the second phase difference generated when the light is transmitted through the light source is an integral multiple of the wavelength of the light. (C) a first optical system disposed between the light source and the liquid crystal display element, the light source light being made into parallel light and incident on the liquid crystal display element; and (d) the liquid crystal display element. Disposed between the projection surface,
A second optical system for projecting light transmitted through the liquid crystal display element onto the projection surface. 19. A light source, (b) a liquid crystal layer, and a first region through which first light having a first center wavelength is transmitted, and a second light having a second center wavelength are transmitted. A first substrate having a pixel region consisting of a second region, and the first substrate sandwiching the liquid crystal layer between the first substrate and the first substrate.
A second substrate having the pixel region corresponding to the first substrate and a first substrate and a second substrate having a refractive index n on a side surface of the first substrate or the second substrate on which a liquid crystal layer is sandwiched. ,
A first phase difference generated when light passes through the conductor film, and the light passes through the liquid crystal layer by substantially the same thickness as the conductor film, which is made of a conductor film having a thickness d. When the center wavelength of transmitted light is λ _i , the difference between the second phase difference R and the generated second phase difference R is 0.8 × λ _i ≦ | (n × d) −R | ≦ 1.2 × λ _i A liquid crystal display element having a stripe-shaped electrode formed by adjusting the refractive index n or the thickness d according to the wavelength λ _i of light passing through the first and second regions so that c) a first light source which is provided between the light source and the liquid crystal display element and is incident on the liquid crystal display element as parallel light;
And (d) a second optical system disposed between the liquid crystal display element and the projection surface and projecting light transmitted through the liquid crystal display element onto the projection surface. Projection type liquid crystal display device. 20. (a) a light source, (b) a liquid crystal layer, and a second substrate forming a plurality of pixel regions by sandwiching the liquid crystal layer between the first substrate and the first or the second substrate. A plurality of filters formed in each of the pixel regions of the second substrate so as to transmit a plurality of lights having different center wavelengths, respectively, and each of the side surfaces sandwiching the liquid crystal layer of the first substrate or the second substrate. In the area corresponding to the filter, the refractive index n,
A conductive film having a thickness of d, and a first phase difference generated when light passes through the conductive film and a first phase difference generated when light passes through the liquid crystal layer by substantially the same thickness as the conductive film. difference between the phase difference R of 2, when the wavelength of transmitted light was set to _{λ i, 0.8 × λ i ≦} | (n × d) -R | transmissive such that ≦ 1.2 × λ _i A liquid crystal display element having a stripe-shaped electrode formed by adjusting the refractive index n or the thickness d according to the wavelength of light to be emitted according to λ _i ; and (c) disposing between the light source and the liquid crystal display element. (D) a first optical system for converting the light source light into parallel light and entering the liquid crystal display element; and (d) disposed between the liquid crystal display element and a projection surface.
A second optical system for projecting light transmitted through the liquid crystal display element onto the projection surface. 21. (a) a light source; (b) a liquid crystal layer; a second substrate sandwiching the liquid crystal layer between the first substrate; and the first substrate or the second substrate. A first phase difference generated when light passes through the conductive film, which is formed of a conductive film having a refractive index of n and a thickness of d on a side surface sandwiching the liquid crystal layer;
When the light is a difference between the second phase difference R caused when transmitting only the conductive film substantially the same thickness as the liquid crystal layer, where the wavelength of the light and lambda _i, 0.8 × a ≦ 1.2 × striped electrode formed by adjusting in accordance with the refractive index n or the thickness d such that the lambda _i to the wavelength lambda _i of the light _{| λ i ≦ | (n ×} d) -R And (d) the liquid crystal disposed between the light source and the liquid crystal display element, wherein the liquid crystal is separated into a plurality of parallel lights having different center wavelengths λ _i and corresponds to the liquid crystal, respectively. First incident on the display element
(E) disposed between the liquid crystal display element and a projection surface;
A second optical system that combines light transmitted through the plurality of liquid crystal display elements and projects the combined light on the projection surface. 22. (a) a light source; (b) a liquid crystal layer; a second substrate sandwiching the liquid crystal layer between first substrates; and the liquid crystal of the first substrate or the second substrate. A first phase difference R _i generated when light passes through the first medium, the first phase difference R _{i including a} first medium and a second medium periodically arranged on a side surface sandwiching the layer; The refractive index or the thickness of the first medium or the second medium is adjusted so that the difference from the second phase difference _Rj generated when the light passes through the second medium is an integral multiple of the wavelength of the light. A liquid crystal display element comprising: a diffraction grating formed by: (c) a light source light, which is disposed between the light source and the liquid crystal display element, is incident on the liquid crystal display element as parallel light. (D) disposed between the liquid crystal display element and a projection surface;
A second optical system for projecting light transmitted through the liquid crystal display element onto the projection surface. 23. (a) a light source; (b) a liquid crystal layer; and a first region through which a first light having a first central wavelength is transmitted and a second light having a second central wavelength. A first substrate having a pixel region consisting of a second region, and the first substrate sandwiching the liquid crystal layer between the first substrate and the first substrate.
A second substrate having the pixel region corresponding to the first substrate; and a first substrate or a second substrate, which is periodically arranged in a first region and a second region on a side surface sandwiching the liquid crystal layer. consisting of a first medium and the second medium, the first and the phase difference R _i that occurs when light passes through the first medium, the light of the second occurring when passing through the second medium difference between the phase difference R _j is, when the wavelength of the light was _{λ i, 0.8 × λ i ≦} | R i -R j | wavelength of the such that ≦ 1.2 × λ _i light lambda a liquid crystal display element comprising a diffraction grating formed by adjusting the refractive index or the thickness of the first medium or the second medium according to _i ; (c) the light source and the liquid crystal display A first light source, which is collimated from a light source disposed between the first and second elements and is incident on the liquid crystal display element;
And (d) a second optical system disposed between the liquid crystal display element and the projection surface and projecting light transmitted through the liquid crystal display element onto the projection surface. Projection type liquid crystal display device. 24. (a) a light source; (b) a liquid crystal layer; a second substrate sandwiching the liquid crystal layer between first substrates; and the liquid crystal of the first substrate or the second substrate. A first phase difference R _i generated when light passes through the first medium, the first phase difference R _{i including a} first medium and a second medium periodically arranged on a side surface sandwiching the layer; the difference between the second phase difference R _j occurring when passing through the second medium, when the wavelength of the light was _{λ i, 0.8 × λ i ≦} | R i -R j | ≦ 1.2 × such that lambda _i, a liquid crystal display characterized by comprising a diffraction grating formed by adjusting the refractive index or thickness of the first medium or the second medium according to the wavelength lambda _i of the light element and, (d) the light source and the disposed between the liquid crystal display device, the liquid each split into a plurality of parallel light beams having different center wavelengths lambda _i source light corresponding First incident on the display device
(E) disposed between the liquid crystal display element and a projection surface;
A second optical system that combines light transmitted through the plurality of liquid crystal display elements and projects the combined light on the projection surface. 25. The projection type liquid crystal display device according to claim 8, wherein a maximum width of a stripe and a maximum width of a slit of the stripe-shaped electrode are 50 μm or less. 26. The method according to claim 26, wherein a stripe region of the stripe-shaped electrode formed on the first substrate is formed to face a slit region of the stripe-shaped electrode formed on the second substrate. A projection type liquid crystal display device according to claim 8. 27. A substrate holding a liquid crystal layer, comprising: a transparent insulating base material; a first medium periodically arranged on a side surface of the transparent insulating base material holding the liquid crystal layer; And a first phase difference R _i generated when light passes through the first medium.
And a refractive index of the first medium or the second medium such that a difference between the light and the second phase difference _Rj generated when the light passes through the second medium is an integral multiple of the wavelength of the light. Alternatively, a substrate comprising a diffraction grating formed by adjusting the thickness. 28. A substrate sandwiching a liquid crystal layer, comprising: a transparent insulating film; and a conductor film on a side surface of the transparent insulating film sandwiching the liquid crystal layer, wherein light passes through the conductor film. And a second phase difference that occurs when the liquid crystal layer passes through the liquid crystal layer by substantially the same thickness as the conductive film, is an integer multiple of the wavelength of the light. A substrate having a stripe-shaped electrode formed by adjusting a refractive index or a film thickness so as to be as small as possible.