JPH05210124A - Active matrix liquid crystal display element and projection type active matrix liquid crystal display device - Google Patents

Abstract

PURPOSE:To improve the transmissivity of light by using the liquid crystal display element constituted by clamping a liquid crystal resin composite which can electrically control a scattering state and a transmission state as a liquid crystal material. CONSTITUTION:This active matrix liquid crystal display element 21 is constituted by clamping the liquid crystal resin composite 27 which consists of a nematic liquid crystal having positive dielectric anisotropy dispersed and held in a resin matrix and with which the refractive index of the resin matrix coincides nearly with the refractive index of the liquid crystal to be used in either of the state at the time of impressing a voltage or not impressing the voltage, between an active matrix substrate 22 provided with active elements 24 for each of picture element electrodes 23 and a counter electrode substrate 25 provided with a counter electrode 26. The liquid crystal particles as the liquid crystal resin composite 27 of this liquid crystal display element 21 are aspherical and the aspect ratio thereof is specified to 1.3 to 2.3. The average particle size, specific dielectric constant anisotropy, elastic constant and viscosity of the liquid crystal are specified to prescribed ranges and color balance is obtd. in respective colors.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an active matrix liquid crystal display device in which an active element is arranged for each pixel electrode and a projection type active matrix liquid crystal display device.

[0002]

2. Description of the Related Art Liquid crystal displays have recently taken advantage of their features such as low power consumption and low voltage drive, and are used in personal word processors, handheld computers and pocket T's.
Widely used for V etc. Among them, an active matrix liquid crystal display element in which an active element is arranged for each pixel electrode is attracting attention and is being actively developed.

Initially, such a liquid crystal display device was manufactured by DSM.
A liquid crystal display element using a (dynamic scattering) type liquid crystal has also been proposed, but the DSM type has a drawback that the current consumption is large because the current value flowing in the liquid crystal is high.
The liquid crystal using (twisted nematic) type liquid crystal has become the mainstream, and has appeared in the market as a pocket TV. T
The N-type liquid crystal has an extremely small leakage current and consumes less power, and is therefore suitable for applications using a battery as a power source.

[0004]

When the active matrix liquid crystal display element is used in the DS mode, the leakage current of the liquid crystal itself is large. For this reason, there is a problem that a large storage capacitance must be provided in parallel with each pixel, and the power consumption of the liquid crystal display element itself increases.

In the TN mode, since the leakage current of the liquid crystal itself is extremely small, it is not necessary to add a large storage capacity, and the power consumption of the liquid crystal display element itself can be reduced. However, the TN mode requires two polarizing plates and thus has a problem that the light transmittance is small. In particular, when performing color display using a color filter, only a few percent of incident light can be used, and a strong light source is required, resulting in an increase in power consumption.

Further, when an image is projected, an extremely strong light source is required, and it is difficult to obtain a high contrast on the projection screen, and there is a problem that heat generation of the light source affects the liquid crystal display element. There is.

Therefore, in order to solve the problem of the TN mode,
A liquid crystal resin composite in which a nematic liquid crystal is dispersed and held in a resin matrix is used, and its scattering-transmission characteristics are utilized.
A mode that can be driven at a low voltage of 10 V or less has been proposed.

However, in the conventional liquid crystal resin composite, there is hysteresis in the voltage-transmittance characteristic,
That is, there is a problem that the transmittance is different between the step-up and the step-down, and therefore, a burn-in phenomenon (an afterimage of more than a second unit) that information of the previous screen remains when the display screen changes may occur. Had a problem.

Further, when a plurality of active matrix liquid crystal display elements having the same structure are used for colorization, the transmission characteristics and the like differ depending on the color, so that the color balance is not sufficient and a particular color is noticeable. However, there is a problem that it is difficult to obtain a clear color display.

[0010]

The present invention has been made to solve the above-mentioned problems and has a high luminance and a high contrast ratio, has no afterimage even in halftone display, and has a liquid crystal resin composite structure. The present invention provides an active matrix liquid crystal display device and a projection type active matrix liquid crystal display device in which a burning phenomenon due to hysteresis is reduced.

That is, the present invention has a plurality of color light sources, a plurality of active matrix liquid crystal display elements on which light from each color light source is incident, and a projection optical system for synthetically projecting the light emitted from the active matrix liquid crystal display elements. In a projection type active matrix liquid crystal display device, an active matrix liquid crystal display element is a nematic having a positive dielectric anisotropy between an active matrix substrate provided with an active element for each pixel electrode and a counter electrode substrate provided with a counter electrode. A liquid crystal resin composite in which liquid crystal is dispersed and held in a resin matrix, and the refractive index of the resin matrix is substantially the same as the refractive index of the liquid crystal used when a voltage is applied or not applied. It is an active matrix liquid crystal display element sandwiched between liquid crystal of each color that is dispersed and held in a resin matrix. Average particle diameter R _x (μm), aspect ratio A _x , relative dielectric anisotropy Δε _{x of} liquid crystal used, elastic constant K33 _x (10 ^-12 N), viscosity η _x (cSt), refractive index anisotropic Sex Δn _x ,
When the dominant wavelength λ _x (μm) of each color is 3 (K33 _x / η _x ) ^0.5 ＞ R _x / A _x ＞ 0.7 (K33 _x / Δε _x ) ^0.5 (1) 1.3 <A _x <2.3 (2) The relationship is satisfied, and Δn _i · R _i / (A _i · λ _i ) ≈Δn _j · R _j / (A _j · λ _j ) (3 ) And satisfy the relationship of d _i / R _i ≈d _j / R _j (4), or the relationship of Δn _i・ d _i ² / λ _i ≈Δn _j・ d _j ² / λ _j (5) The projection type active matrix liquid crystal, characterized in that the major axis direction of the liquid crystal particles is two-dimensionally almost random in the cut surface perpendicular to the electrode surface of the liquid crystal resin composite. A display device is provided.

Further, the color light source is a color light source of RGB three colors, and x satisfies the expressions (1) and (2) for all three RGB colors, and Δn _R · R _R / (A _R · λ _R ) ≈Δn _G · R _G / (A _G・ λ _G ) ≈Δn _B・ R _B / (A _B・ λ _B ) (3A) and d _R / R _R ≈d _G / R _G ≈d _B / R _B (4A) Characterized by satisfying the relation or satisfying the relation of Δn _R・ d _R ² / λ _R ≈ Δn _G・ d _G ² / λ _G ≈ Δn _G・ d _G ² / λ _G (5A) A projection type active matrix liquid crystal display device is provided.

Further, the refractive index anisotropy Δn _{x of} the liquid crystal used in these active matrix liquid crystal display elements is λ _i >.
When λ _j , a projection type active matrix liquid crystal display device characterized by satisfying the relationship of Δn _j ≦ Δn _{i and} a relationship of 0.2 <R _x · Δn _x <0.7 (6) A projection type active matrix liquid crystal display device, and a projection type active matrix liquid crystal display device characterized by satisfying the relationship of Δn _x ² _· Δε _x / (K33 _x · η _x )> 0.0011 (7). Is provided.

Furthermore, the maximum effective applied voltage V _x (V) applied to the liquid crystal resin composite is 4R _x <A _x · d _x <15R _x (8) 0.8R _x · V _x <A _x · d A projection type active matrix liquid crystal display device characterized by satisfying the relationship of _x <1.8R _x · V _x (9).

Further, a nematic liquid crystal having a positive dielectric anisotropy is provided between an active matrix substrate having color filters of RGB three colors, each pixel electrode having an active element, and a counter electrode substrate having a counter electrode. Is dispersed and held in the resin matrix, and the liquid crystal resin composite is sandwiched so that the refractive index of the resin matrix is substantially the same as the refractive index of the liquid crystal used when voltage is applied or not applied. In the active matrix liquid crystal display device formed as described above, the average particle diameter R (μm) of the liquid crystal dispersed and held in the resin matrix, its aspect ratio A, the interelectrode gap d _x (μm) of each color, and the relative permittivity of the liquid crystal Anisotropy Δε, elastic constant K3
3 (10 ^-12 N), viscosity η (cSt), refractive index anisotropy Δn, and dominant wavelength λ _x (μm) of each color are 3 (K33 / η) ^0.5 > R / A> 0.7 (K33 / Δε ) ^0.5 (1B) 1.3 <a <2.3 (2B) 0.2 <R · Δn <0.7 (6B) Δn 2 · Δε / (K33 · η)> 0.0011 (7B) 4R <a · d G <15R (8B) Satisfying the relationship, and satisfying the relationship of at least two colors of RGB, i ≠ j, and satisfying the relationship of d _i ² / λ _i ≈d _j ² / λ _j (5B), the electrode surface of the liquid crystal resin composite A projection-type active-matrix liquid crystal display element, characterized in that the major axis direction of liquid crystal particles is two-dimensionally substantially random in a cross section perpendicular to the A projection-type active matrix liquid crystal display device characterized by being combined with a projection optical system.

In the projection type active matrix liquid crystal display device of the present invention, the liquid crystal material sandwiched between the active matrix substrate and the counter electrode substrate is a liquid crystal resin composite capable of electrically controlling the scattering state and the transmitting state. Since the active matrix liquid crystal display element sandwiching the
No polarizing plate is required, and the light transmittance during transmission can be greatly improved. Furthermore, the average particle size R _x (μ
m) and the gap d _x (μm) between the two electrodes are set for each color, so that when the colors are mixed in the projection display, a color balance is good, a bright display with a good contrast ratio is obtained.

Further, the problems such as the alignment treatment essential for the TN type liquid crystal display element and the destruction of the active element due to the generated static electricity can be avoided, so that the manufacturing yield of the liquid crystal display element can be greatly improved.

Further, since this liquid crystal resin composite is in the form of a film after being cured, problems such as short circuit between substrates due to pressurization of substrates and breakage of active elements due to movement of spacers are unlikely to occur.

Further, this liquid crystal resin composite has a specific resistance equivalent to that in the conventional TN mode, and it is not necessary to provide a large storage capacitor for each pixel electrode as in the DS mode, and the active element can be designed. It is easy and the power consumption of the liquid crystal display element can be kept low. Therefore, the manufacturing process is easy because the manufacturing process of the conventional liquid crystal display device of the TN mode can be performed only by removing the alignment film forming process.

The specific resistance of the liquid crystal resin composite is 5 × 10 5.
It is preferably ⁹ Ωcm or more. Furthermore, in order to minimize the voltage drop due to leakage current or the like, 10 ¹⁰ Ωcm or more is more preferable, and in this case, it is not necessary to give a large storage capacitance to each pixel electrode.

As the active element provided on the pixel electrode,
There are transistors, diodes, non-linear resistance elements, etc.
If necessary, two or more active elements may be arranged in one pixel. A liquid crystal display device is obtained by sandwiching the liquid crystal resin composite between an active matrix substrate having such an active element and a pixel electrode connected thereto and a counter electrode substrate having a counter electrode.

The liquid crystal display device of the present invention can be used as both a direct-view display device and a projection display device. When used as a direct-view display element, a display device may be configured by combining a backlight, a lens, a prism, a mirror, a diffusion plate, a light absorber, a color filter, etc., depending on the desired display characteristics.

The liquid crystal display device of the present invention is particularly suitable for a projection type display device, and can be combined with a light source for projection, a projection optical system and the like to form a projection type liquid crystal display device.
A plurality of color light sources and a projection optical system are used as the projection type active matrix liquid crystal display device of the present invention. As these color light sources and projection optical systems, conventionally known projection optical systems such as projection light sources and lenses can be used. Normally, the plurality of liquid crystal display elements are arranged corresponding to the respective color light sources, and an image is synthesized by these. It suffices if it is adapted to project.

As the color light source, a dedicated light source may be used for each color, or light from one light source may be dispersed and used. The light emitted from this color light source is made incident on the active matrix liquid crystal display element. In the present invention, these plural active matrix liquid crystal display elements are used with their characteristics matched for each color of the light source. Light emitted from these active matrix liquid crystal display elements is mixed and projected. As a result, a bright, well-balanced projection image with a high contrast ratio can be obtained.

As a result, in the present invention, as a liquid crystal display element, an active matrix substrate provided with an active element for each pixel electrode and a counter electrode substrate provided with a counter electrode are provided.
Nematic liquid crystals with positive dielectric anisotropy are dispersed and held in the resin matrix so that the refractive index of the resin matrix is almost the same as the refractive index of the liquid crystal used when voltage is applied or not applied. Since the liquid crystal display element in which the transmission-scattering type liquid crystal resin composite is sandwiched is used, it has a feature that bright and high contrast can be easily obtained.

Specifically, a liquid crystal resin composite comprising a resin matrix having a large number of fine pores formed therein and a nematic liquid crystal having a positive dielectric anisotropy filled in the pores is used. This liquid crystal resin composite is sandwiched between an active matrix substrate and a counter electrode substrate to form a liquid crystal display element. The applied state of voltage between the electrodes of the liquid crystal display element changes the refractive index of the liquid crystal, and the relationship between the refractive index of the resin matrix and the refractive index of the liquid crystal changes. The state becomes a scattering state when the refractive index is different.

In this case, it is preferable that the refractive index of the resin matrix substantially matches the ordinary refractive index (n _o ) of the liquid crystal used. Also, the refractive index anisotropy Δ of this liquid crystal
It is preferable to use a liquid crystal resin composite having n of 0.18 or more.

A liquid crystal resin composite comprising a resin matrix having a large number of fine pores and liquid crystals filled in the pores has a structure in which liquid crystals are contained in liquid bubbles such as microcapsules. However, the individual microcapsules do not have to be completely independent, and liquid bubbles of individual liquid crystals may communicate with each other through a slit like a porous body.

The liquid crystal resin composite used in the liquid crystal display device of the present invention is prepared by mixing the nematic liquid crystal and the curable compound constituting the resin matrix into a solution or a latex, which is then photocured and heat-cured. The cured product may be separated by curing, curing by removing the solvent, reaction curing, or the like so that the nematic liquid crystal is dispersed in the resin matrix.

This curable compound is preferably a photocurable or thermosetting type because it can be cured in a closed system. In particular, the use of a photocurable curable compound is preferable because it can be cured in a short time without being affected by heat.

As a specific manufacturing method, a cell is formed by using a sealing material as in the case of a conventional normal nematic liquid crystal, and an uncured mixture of a nematic liquid crystal and a curable compound is injected from an injection port, After sealing, the composition can be cured by irradiation with light or heating.

In the case of the liquid crystal display element of the present invention,
For example, an active matrix in which an uncured mixture of a nematic liquid crystal and a curable compound is supplied to a substrate provided with a transparent electrode as a counter electrode without using a sealing material, and then an active element is provided for each pixel electrode. It is also possible to stack the substrates and cure them by light irradiation or the like.

Of course, thereafter, a sealing material may be applied to the periphery to seal the periphery. According to this production method, the uncured mixture of the nematic liquid crystal and the curable compound may be simply supplied by roll coating, spin coating, printing, coating with a dispenser, etc., so that the injection step is simple and the productivity is high. Very good.

The uncured mixture of the nematic liquid crystal and the curable compound contains ceramic particles for controlling the substrate gap, plastic particles, spacers such as glass fibers, pigments, dyes, viscosity modifiers and the like. You may add the additive which does not have a bad influence on the performance of.

By curing an element that is in a scattering state when no voltage is applied in such a state that a sufficiently high voltage is applied only to a specific portion during this curing step, that portion can be kept in a light transmitting state at all times. Therefore, when there is something that is desired to be fixedly displayed, such a normal transmission portion may be formed. On the contrary, in the case of an element that is in the transmissive state when no voltage is applied, the ordinary scattering portion can be formed in the same manner.

The higher the transmittance of the liquid crystal display device using this liquid crystal resin composite in the transmissive state, the better, and the haze value in the scattering state is preferably 80% or more.

In the present invention, the refractive index of the resin matrix (after curing) is the same as the refractive index of the liquid crystal used when the voltage is applied or not applied, and in the opposite state, the refractive index of the resin matrix is the same. , Is not matched with the refractive index of the liquid crystal used.

As a result, when the refractive index of the resin matrix and the refractive index of the liquid crystal match, light is transmitted, and when they do not match, light is scattered (white turbidity). The scattering property of this element is higher than that of the conventional DS mode liquid crystal display element, and a display with a high contrast ratio can be obtained.

In the present invention, the refractive index of the resin matrix (after curing) is made to match the ordinary refractive index (n _o ) of the liquid crystal to be used, especially when a voltage is applied. preferable. As a result, since a transmissive state is achieved when a voltage is applied, the transmissivity during light transmission is high and the light is evenly transmitted, so that the display contrast ratio is improved.

An object of the present invention is to provide an optimum configuration of a projection type active matrix liquid crystal display device using an active matrix liquid crystal display element sandwiching this liquid crystal resin composite. That is, even in gradation display, a quick response, a display without image sticking (the rest of the image of a second or more) can be obtained, the color balance is good, the transmittance is high at the time of transmission, and the scattering property at the time of scattering is high. (Light-shielding), bright,
The present invention provides an active matrix liquid crystal display device having a large contrast ratio and a projection type active matrix liquid crystal display device.

The factors that determine the electro-optical characteristics of the active matrix liquid crystal display device using the above liquid crystal resin composite are the refractive index (ordinary light refractive index n _o , extraordinary light refractive index n _e ) and relative dielectric constant of the liquid crystal used. (Ε //, ε⊥, // and ⊥ are parallel and perpendicular to the liquid crystal molecular axis, respectively), viscosity η, elastic constant K33,
And the refractive index n _{p of the} resin used, the relative dielectric constant ε _p , the elastic modulus, and the average particle diameter R _{x of} the liquid crystal dispersed and held in the resin matrix, the volume fraction Φ, the gap between both electrode substrates (the liquid crystal resin composite). Thickness) d _x , the maximum effective applied voltage V _x applied to the liquid crystal resin composite in the pixel portion by the active element, and the like.

Here, the liquid crystal average particle diameter R _x means the maximum diameter of the particles when the liquid crystals are independent particles or particles in which some of them are in communication, and in the case of a structure in which most of the liquid crystals are in communication. Means the maximum diameter of the region where the orientations of the liquid crystal directors are correlated with each other.

The liquid crystal dispersed and held in the resin matrix is preferably independent particles or particles partially communicating with each other. This is effective in that it can be driven at a low voltage and has both high scattering ability and high transparency. Scattering is caused by the presence of the liquid crystal / resin interface. For this reason,
The larger the area of this interface, the higher the scattering property. In order to increase the area of this interface with a certain optimum liquid crystal particle diameter, the amount of liquid crystal separated from the resin is increased independently, that is,
It is important to increase the liquid crystal particle density.

However, when the amount of liquid crystal separated from the resin is increased, the respective liquid crystal particles come to communicate with each other,
Furthermore, all the liquid crystals come to have a structure in which they communicate with each other, which leads to the loss of the liquid crystal interface separated from the resin, leading to a decrease in the scattering ability.

In order to reduce the driving voltage, it is important that the liquid crystals held in the resin have substantially the same driving voltage. For this purpose, it is advantageous for the liquid crystal to have a clear interface with the resin, and loss of the interface leads to dispersion of the drive voltage, which tends to cause a decrease in contrast ratio and an increase in drive voltage. For this reason, it is preferable that the liquid crystal dispersed and held in the resin is independent particles that are present at a high density or particles that are partially connected.

The electro-optical characteristics of the active matrix liquid crystal display device using the liquid crystal resin composite of the present invention have a high scattering property when voltage is applied or not applied, and a high transmission property when the other is applied. That has a high display contrast ratio, has a high responsiveness even in gradation display, and is free from afterimages (remaining images in seconds or less) and burn-in (remaining images in seconds or more). Is desired to be obtained. When projection type display is performed using such a liquid crystal display element, high brightness and high contrast ratio display can be obtained. In order to obtain such a display, it is necessary that the above factors have an optimum relationship.

Among these factors, the particularly important factor that determines the electro-optical characteristics of the active matrix liquid crystal display element is the refractive index of the liquid crystal used (refractive index anisotropy Δn = n _e −
n _o ), relative dielectric anisotropy Δε, viscosity η, elastic constant K33, average particle size R of liquid crystal, aspect ratio A, particle size distribution, gap between both electrode substrates, d, depending on the dominant wavelength λ of the color light source. , The average particle diameter R 1 of the liquid crystal and the gap d between the electrode substrates are determined and optimized for each liquid crystal display element.

Refractive index anisotropy of liquid crystal used Δn (= n _e −
n _o ) contributes to the scattering property of the liquid crystal, and is preferably a certain value or more in order to obtain high scattering property.
n> 0.18 is preferable, and Δn> 0.22 is particularly preferable. Further, it is preferable that the ordinary refractive index n _o of the liquid crystal used is substantially equal to the refractive index n _p of the resin matrix, and at this time, high transparency can be obtained when a voltage is applied. More specifically, n _o -0.03 <n _p <
It is preferable to satisfy the relationship of n _o +0.05.

The greatest object of the present invention is to provide an active matrix liquid crystal display device using this liquid crystal resin composite, and an active matrix liquid crystal display device and a projection type active matrix liquid crystal display device in which the phenomenon of burning due to histteria is reduced. That is.

Since the liquid crystal resin composite is driven in an off state and a sufficiently high on state (above the saturation voltage) when it is statically driven, it has a responsivity of several tens of milliseconds or less and is generally suitable for high-speed display. It is suitable. However, in gradation display, a voltage lower than the saturation voltage is also used to display halftone, and there is a state in which the response is slower than in static drive. The response in gradation display tends to be slower as the display on the low voltage side (dark display) is slower. Especially, the change from the OFF state to the low transmittance state is the slowest, and the number of responses during static drive It may be more than ten times slower.

The average particle size R of the liquid crystal dispersed and held in the resin matrix is a very important factor and contributes to the scattering property of the liquid crystal and the operating characteristics of the liquid crystal when a voltage is applied. The important factors that determine the response during gradation display are the average particle size R of the liquid crystal retained in the resin, its shape, the relative dielectric anisotropy Δε of the liquid crystal used, the elastic constant K33, and the viscosity. η, etc.

A display with less image sticking can be obtained even in gradation display because the average particle size R (μm) and aspect ratio A of the liquid crystal dispersed and held in the resin matrix and the relative dielectric constant of the liquid crystal used are different. Isotropic Δε, viscosity η (cSt), elastic constant K33 (10
^-12 N) uses one type of liquid crystal, that is, multicolor display with one element, 3 (K33 / η) ^0.5 > R / A> 0.7 (K33 / Δε) ^0.5 ( 1B) 1.3 <A <2.3 (2B).

When a plurality of liquid crystals are used by using a plurality of elements, 3 (K33 _x / η _x ) ^0.5 > R _x / A _x > 0.7 (K33 _x / Δε _x ) for each color. It is when the relationship ^0.5 (1) 1.3 <A _x <2.3 (2) is satisfied.

Further, a display without an afterimage can be obtained even in gradation display, when one kind of liquid crystal is used, the relationship of Δn ² _· Δε / (K33 · η)> 0.0011 (7B) is satisfied. It is time to satisfy, and when a plurality of liquid crystals are used, it is time to satisfy the relationship of Δn _x ² _· Δε _x / (K33 _x · η _x )> 0.0011 (7).

In the range of the equation (1) or (1B),
The torque acting on the liquid crystal at each voltage during gradation display can be balanced, display with less afterimage can be obtained, and the voltage required for driving the liquid crystal can be suppressed low. Further, the effect is large by satisfying the range of the expression (7) or (7B). Particularly, if the value of the equation (7) or (7B) is 0.0014 or more, this effect is large and preferable. The physical properties of the liquid crystal used here are values at room temperature.

In the conventional liquid crystal resin composite,
There is a hysteresis in the voltage-transmittance characteristic, which has been a problem in gradation display. Hysteresis is a phenomenon in which the transmittance is different in the process of increasing the voltage and the process of decreasing the voltage. If there is hysteresis, the information on the previous screen will remain for a relatively long time (in seconds or more) at the time of gradation display, that is, the phenomenon of image sticking easily occurs, which deteriorates the image quality.

One of the causes of the existence of hysteresis in the liquid crystal resin composite is due to the structure in which the liquid crystal is dispersed and held in the resin matrix in the liquid crystal resin composite. That is, it is considered that hysteresis exists due to the interaction between the liquid crystal particles that are separated and are present in the resin matrix. The size of this hysteresis is determined by the elastic energy stored in the liquid crystal held in the resin matrix, the electrical energy due to the voltage applied from the outside, and the interaction energy between the liquid crystals separated in the resin matrix. Is done.

Therefore, the hysteresis can be reduced by optimizing this energy balance,
An excellent display without image sticking can be obtained even in gradation display.

An object of the present invention is to obtain a liquid crystal display device having a high contrast ratio, a high brightness, an excellent responsiveness, and a reduced hysteresis.
It is to obtain an active matrix liquid crystal display device and a projection type active matrix liquid crystal display device that can be driven by an active element or a driving circuit for use.

The important factors that determine the above energy balance are the average particle size R of the liquid crystal dispersed and held in the resin matrix, the shape of the liquid crystal particles, the relative permittivity of the liquid crystal and its anisotropy Δε, viscosity η, The elastic constant K 33, the dielectric constant ε _p of the resin matrix, and the like. When optimizing for the above purpose, the optimization should be performed considering that this energy balance is closely related to the voltage-transmittance characteristic of the device and the dynamic characteristic (responsiveness) of the liquid crystal. is important.

The average particle diameter R of the liquid crystal is an important factor,
It is closely related to scattering characteristics, responsiveness, operating electric field, etc. R
Becomes larger, the electric field required for driving becomes smaller, but the response becomes slower. When R is small, elastic energy accumulated per unit liquid crystal amount is large and the response speed is high, but a high electric field is required for driving.

The viscosity η of the liquid crystal and the relative dielectric constant anisotropy Δε are also factors that are deeply related to the response. The smaller the viscosity and the larger the relative dielectric constant anisotropy, the faster the response speed. Also, Δ
ε is also related to the electric field required for driving, and the larger Δε, the smaller the required electric field.

The elastic constant of the liquid crystal determines the elastic energy accumulated in the liquid crystal, but in the liquid crystal resin composite, the bend energy due to K33 plays a large role,
It is deeply involved in response characteristics and drive characteristics, that is, elastic torque acting on the liquid crystal. To reduce the hysteresis, the elastic constant
Larger K33 is more advantageous, and in this case, improved responsiveness is also expected. But when K33 gets too big,
Since this leads to an increase in the driving electric field, it can be selected depending on the balance with other liquid crystal physical properties (for example, Δn, Δε, η, etc.).

The shape of the liquid crystal is an important factor for reducing the hysteresis. That is, because the strain of the liquid crystal particles held in the resin matrix can change the elastic energy accumulated per unit liquid crystal amount,
As a result, the energy balance can be controlled.

As the shape of the liquid crystal, it is not preferable that the liquid crystal has a very complicated unevenness, but a very high driving voltage is required, but a spheroidal shape is preferable. At this time, the average particle size is the average of the diameter a on the major axis (that is, the maximum diameter) weighted by volume, and the aspect ratio A is the diameter a on the major axis divided by the diameter b on the minor axis. / b.

When the aspect ratio A is small (A <1.3
), The increase in elastic energy due to the shape of the liquid crystal particles is small, and the contribution to the overall energy balance is not large. Therefore, although the drive voltage is small, the hysteresis is difficult to reduce. As the aspect ratio A increases, the amount of increase in elastic energy increases, which reduces hysteresis and further increases the response speed.

However, as the aspect ratio A becomes larger, the voltage required for driving becomes higher, and the aspect ratio A becomes higher.
When becomes larger, the contrast ratio may decrease due to the decrease in scattering ability. Therefore, the optimum range of the aspect ratio A can be obtained in consideration of the response characteristics and the driving characteristics.

The conditions obtained from the above viewpoints are shown below. When using one type of liquid crystal, that is, when displaying multicolored color with one element, 3 (K33 / η) ^0.5 > R / A> 0.7 (K33 / Δε) ^0.5 (1B) 1.3 <A < 2.3 (2B) Further, when using a plurality of liquid crystals using a plurality of elements, for each color, 3 (K33 _x / η _x ) ^0.5 ＞ R _x / A _x ＞ 0.7 (K33 _x / Δε _x ) ^0.5 (1) 1.3 <A _x <2.3 (2). In the range represented by the formulas (1B), (2B) or (1), (2), a liquid crystal display device having a well-balanced response characteristic and driving characteristic and reduced hysteresis can be obtained.

In the present invention, the liquid crystal particles have an aspect ratio and are non-spherical, and at the same time, the distribution of the non-spherical liquid crystal particles in the direction of the major axis is important. That is, in the present invention, the long axis of the liquid crystal particles is oriented in a two-dimensional almost random direction in the cut surface of the liquid crystal resin composite in the direction perpendicular to the electrode surface.

FIG. 4 is a perspective view for explaining the state, and FIG. 5 is a sectional view thereof. In FIG. 4, 31 and 32 are substrates, 33 and 34 are electrodes, and 35 is a liquid crystal resin composite,
Reference numeral 36 indicates a cross section perpendicular to the electrode surface. Figure 5
It is a cross-sectional view showing a cut surface 36 in a direction perpendicular to the electrode surface,
43 and 44 are electrodes, 45 is a liquid crystal resin composite, 47 is one liquid crystal particle, 48 is the major axis direction of the particle, and 49 is a direction perpendicular to the electrode. θ represents the angle formed by the long-axis direction 48 of the liquid crystal particles and the direction 49 perpendicular to the electrodes.

In the present invention, this angle θ is oriented in a substantially random direction within this cross section. In addition,
Random here means one pixel, usually 50 μm to 300
It may be macroscopically random in the order of μm square. A more preferable state is that the angle θ of the major axis of the particles is random within a range of several μm or less in the pixel, that is, a range of about 10 times or less of the wavelength used. Furthermore, when the liquid crystal resin composite has a plurality of layers, the first layer is inclined by 30 ° in the major axis direction of the liquid crystal particles, and the second layer is inclined by 90 °. It is also possible to use those having different inclination angles for several layers. That is, it suffices that the major axis direction of the liquid crystal particles is substantially random when viewed in the vertical direction.

However, it is extremely difficult to obtain such a controlled inclination angle in manufacturing, and it is preferable that the inclination angle is not 30 degrees and is random at various angles. Since the effect of is large, it is preferable that it is made truly random. In this way, by making the cut surface perpendicular to the electrode surface two-dimensionally almost random, the burn-in phenomenon due to hysteresis can be significantly reduced.

Further, in the present invention, it is more preferable to make the three-dimensional almost random, including the depth direction of FIG. This is preferable because the amount of transmitted light can be accurately controlled when the incident light is randomly polarized light. This is also important in order to take advantage of a bright display that does not use a polarizing plate, which is the greatest merit when the liquid crystal display element of the present invention is used as a projection type display device. If there is polarized light,
In order to be most sensitive to the polarization direction, it is preferable to make the cut surface perpendicular to the electrode surface two-dimensionally almost random.

The optimum R / A region is determined by the balance of the electrostatic energy of the liquid crystal, the elastic energy, and the torque acting on the liquid crystal, so that a response that does not hinder the display can be obtained.
The upper limit of R / A is 3 (K33 / η) ^0.5 and the lower limit is 0.7 (K33 / Δε) ^0.5.
It is represented by.

The elastic constant of the liquid crystal determines the elastic energy accumulated in the liquid crystal, and in the liquid crystal resin composite, the bend energy due to the elastic constant K33 plays a large role, and acts on the response characteristic, the driving characteristic, that is, the liquid crystal. Deeply involved with elastic torque. The relative dielectric constant anisotropy is related to the electric torque acting on the liquid crystal, that is, the electric field required for driving, and the viscosity is related to the viscous torque acting on the liquid crystal. It is the above-described relationship that the balance of these torques is optimized. Within this range, response characteristics suitable for displaying a moving image in gradation display can be obtained with a relatively low electric field.

In order to achieve a high contrast ratio, it is necessary that the off-time scattering power is large. The scattering power per unit operating liquid crystal amount of the liquid crystal resin composite is R · Δn / λ (λ =
(Wavelength of light of each color). Therefore, when one liquid crystal is used, the relationship of 0.2 <R · Δn <0.7 (6B) is satisfied, and when a plurality of liquid crystals are used, 0.2 <R _x · Δn _x <0.7 (6) is satisfied. Try to satisfy the relationship.

The average particle size R of the liquid crystal display device is (6) or
When it is smaller than the range of the formula (6B), the response speed becomes faster, but the scattering ability per unit liquid crystal becomes lower and the voltage required for driving becomes higher. Conversely, if the average particle size R is (6) or
When it is larger than the range of the formula (6B), it can be driven at a low voltage, but the scattering ability per unit liquid crystal amount is lowered and the response speed becomes slow.

The particle size of this liquid crystal is preferably uniform. When the particle diameters are distributed, large liquid crystal particles lead to a decrease in scattering ability, and small liquid crystal particles lead to an increase in driving electric field, resulting in an increase in driving voltage and a decrease in contrast. The dispersion σ of the particle diameter is preferably within 0.25 times the average particle diameter, more preferably within 0.15 times. The average particle size and the dispersion are the weighted average and dispersion.

The electrode substrate gap d is also an important factor. Increasing d improves the scattering property. However, if d is too large, it becomes difficult to achieve sufficient transparency during transmission, a high voltage is required for driving, power consumption increases, and conventional active elements for TN and driving ICs are used. The problem arises that it cannot be used. Also, if d is made small, it can be driven at a low voltage, but the scattering property will decrease.

Therefore, in order to achieve both the scattering property and the drivability, when the product A · d of the d (μm) aspect ratio A is one liquid crystal, the electrode substrate in the intermediate wavelength region is used. In the gap, satisfy the relation of 4R <A · d <15R (8C). In the case of three colors of RGB, since the intermediate region is green, the relationship of 4R <A · d _G <15R (8B) is satisfied (d _G is the electrode substrate gap in the green part), and when using multiple liquid crystals , 4R _x <A _x · d _x <15R _x (8).

In the case of three colors of RGB, when the average particle size R _G of the liquid crystal display element with respect to the green light source is smaller than the range of the above formula, the scattering property is stronger on the short wavelength side. It also becomes dependent, and since a high electric field is required for the operation of the liquid crystal, there arises a problem that power consumption increases. On the contrary, when the average particle size R _G is larger than the range of the above formula, although the wavelength dependence of the scattering property is small, the scattering property becomes weak over the entire visible light region, the contrast ratio decreases, and the scattering from the time of transmission. There is also a problem that the response to time becomes slow. Therefore, the above range is set.

In this case, the electrode substrate gap d _G of the liquid crystal display element with respect to the green light source is also an important factor. Increasing d _G improves the scattering property. However, if d _G is too large, a high voltage is required for driving, which causes problems such as increased power consumption and the inability to use conventional active elements for TN and driving ICs. Also, if d _G is made small, it can be driven at a low voltage, but the scattering property will decrease. For this reason,
In order to achieve both diffusivity and drivability, d _G (μm) is
The above formula is satisfied.

Further, in order to make the characteristics of each color uniform, in the target liquid crystal display element, Δn · R / λ and Δn · d ² /
Make λ approximately the same. Specifically, the following is done. Δn _i・ R _i / (A _i・ λ _i ) ≈Δn _j・ R _j / (A _j・ λ _j ) (3) and satisfy the relationship of d _i / R _i ≈d _j / R _j (4) Or satisfy the relationship of Δn _i · d _i ² / λ _i ≈Δn _j · d _j ² / λ _j (5).

Under the conditions of the expressions (3) and (4), by adjusting the phase condition of light, the scattering intensity by the liquid crystal particles can be made almost uniform with respect to the color, and in the off state or the halftone display state. It is possible to obtain a display having a good color balance by substantially equalizing the voltage transmittance characteristics. At the time of actual color display, a color display with a better color balance can be obtained by combining with a fine adjustment by a driving circuit. The characteristics for each color can also be made uniform by making the average particle diameter of the liquid crystal for each color constant and matching Δn _x · d _x ² / λ _x as in formula (5).

Therefore, in the set of liquid crystal display elements whose characteristics are desired to be uniform, color correction can be performed by either of the relationships of the equations (3) and (4) or the equation (5). When three or more liquid crystal display elements are used for three or more colors, some of them satisfy the relations of formulas (3) and (4), and some of them satisfy the relation of formula (5). You may do it. If there is little difference to be corrected among some of these colors, color correction should be performed using equations (3), (4), or (5) only for some of the most influential colors. You can also

Specifically, even in the case of RGB three colors, the best correction can be made by performing color correction between all three liquid crystal display elements by the formulas (3), (4) or (5). Among the three liquid crystal display elements, between a pair of liquid crystal display elements,
The color correction may be performed using the formulas (3), (4), or (5).

Specifically, they are as follows, respectively. Δn _R・ R _R / (A _R・ λ _R ) ≈Δn _G・ R _G / (A _G・ λ _G ), and d _R / R _R ≈
d _G / R _G , Δn _R・ R _R / (A _R・ λ _R ) ≒ Δn _B・ R _B / (A _B・ λ _B ), and d _R / R _R ≒
d _B / R _B , Δn _G・ R _G / (A _G・ λ _G ) ≒ Δn _B・ R _B / (A _B・ λ _B ), and d _G / R _G ≒
d _B / R _B , satisfies at least one of the three relationships,
Or Δn _R・ d _R ² / λ _R ≈ Δn _G・ d _G ² / λ _G , Δn _R・ d _R ² / λ _R ≈ Δn _B・ d _B ² / λ _B , Δn _G・ d _G ² / λ _At least one of the three relations of _G ≈ Δn _B · d _B ² / λ _B is satisfied.

When performing color correction for all three RGB colors,
Equations (3), (4), and (5) are as follows, respectively. Δn _R・ R _R / (A _R・ λ _R ) ≒ Δn _G・ R _G / (A _G・ λ _G ) ≒ Δn _B・ R _B / (A _B・ λ _B ) (3A) and d _R / R Satisfies the relationship of _R ≒ d _G / R _G ≈d _B / R _B (4A), or Δn _R・ d _R ² / λ _R ≈ Δn _G・ d _G ² / λ _G ≈ Δn _B・ d _B The relation of ² / λ _B (5A) is satisfied.

Even if all are color-corrected, the condition between equations (3) and (4) is applied between RGs, and in this case between GBs, (5)
You may make it perform on condition of a formula.

Particularly, regarding the color correction among the three colors of RGB,
In general, the optical characteristics of red (R) are greatly different from the optical characteristics of green (G) and blue (B), so correction between R and G, B is most important. Therefore, for example, although the load on the drive circuit side increases, the same liquid crystal display element is used for G and B, and the correction between G and B is performed by the drive circuit.
For the correction between R and G and B, the above equations (3), (4) or
It is also possible to do so in relation to equation (5). In this case, two types of liquid crystal display elements may be produced instead of three types of liquid crystal display elements as RGB liquid crystal display elements, which is an advantage in production.

Under the condition of the expression (5), although it is slightly disadvantageous in terms of contrast ratio and the like in the cases of the expressions (3) and (4), the scattering characteristics in each color can be almost equalized and the color balance can be maintained. It is possible to obtain a good display. In this case, when the liquid crystal used for each color is the same, the characteristics for each color can be almost equalized only by the gap between the electrodes, the manufacturing is easy, and by combining with the color filter,
It is possible to display a plurality of colors with well-balanced colors by using one liquid crystal display element.

When the same liquid crystal is used and when it is used together with a color filter, the equation (5) is set as d _i ² / λ _i ≈d _j ² / λ _j (5B) with i ≠ j. When a color filter is used, it is possible to obtain a display with good color balance by aligning the gaps between the electrodes according to the formula (5B) in the color filter portion of each color.

Also in this case, when the three colors of RGB are used, the equation (5B) is as follows. d _R ² / λ _R ≈d _G ² / λ _G ≈d _B ² / λ _B (5C) However, also in this case, for example, between G and B, the gap between the electrodes is not corrected, and R, G and Correct only between B,
It is also possible to perform color correction between G and B by a drive circuit. In this case d _R ² / λ _R ≈d _G ² / λ _G or d _R ² / λ _R ≈
It becomes d _B ² / λ _B.

The liquid crystal particle diameter that maximizes the scattering intensity at the time of off is deeply involved in λ and Δn, and as described above, ΔnR / λ
The scattering intensity per unit operation liquid crystal is determined by. Therefore, when trying to match the characteristics for each color using equations (4) and (5),
If the same liquid crystal is used for each color, it is necessary to increase the average particle diameter of the liquid crystal used on the longer wavelength side. Considering the characteristic that the response time increases as the average particle size increases,
In particular, a liquid crystal used on the longer wavelength side preferably has a larger Δn.

The liquid crystal to be used can be selected in consideration of the relationship between the viscosity, the elastic constant, the relative dielectric constant anisotropy and the average particle size shown in the equations (1) and (7). With respect to the liquid crystal, it is possible to obtain a moving image display in which the characteristics for each color are uniform according to the desired response characteristics, drive voltage, contrast ratio, and the like. The refractive index anisotropy Δn of the liquid crystal used is preferably Δn> 0.18 as described above. When the liquid crystal is changed for each color, the above formula is satisfied for each liquid crystal. Preferably.

When the color balance is corrected under the condition of (3), (4) or (5), the refractive index anisotropy of each color is
It can be set within the above range, and λ _i > λ _j
In this case, it is preferable that the relationship of Δn _j ≦ Δn _i is satisfied. Specifically, when three colors of RGB are used as the color light source, it is preferable that Δn _B ≦ Δn _G ≦ Δn _R.

The condition of Δn _B ≈Δn _G ≈Δn _R substantially equalizes Δn in the liquid crystal display elements of respective colors, and has an advantage that the same liquid crystal can be used for each element. In this case, the characteristics for each color can be corrected by the average particle diameter of the liquid crystal and the interelectrode gap by the equations (3) and (4), or by the interelectrode gap by the equation (5) or (5C).

Under the condition of Δn _B <Δn _G <Δn _R , the liquid crystal of the liquid crystal display element used in the long wavelength region has a larger Δn, so that the structure of the liquid crystal resin composite and the gap between the electrodes are different for each color. It has the advantage that it does not need to be changed significantly. In particular, when Δn / λ is substantially the same for each color, it is possible to achieve color balance by using a liquid crystal resin composite having substantially the same structure and using substantially the same interelectrode gap.

Δn _B ≈Δn _G <Δn _R or Δn _B <Δn _G ≈Δn _R
The condition of 3 is that the characteristics of 3 colors are almost equalized by 2 kinds of liquid crystal, and the characteristics of each color are as follows: (3), (4) The average particle diameter of liquid crystal and the gap between electrodes, or (5) both the inter-electrode gap d _X may be corrected by the inter-electrode gap by the formula
The absolute value of may be selected according to the applied voltage used so that the display brightness and the contrast ratio are optimized. The maximum applied voltage and the gap between both electrodes are preferably in the following ranges. 0.8R _x・ V _x <A _x・ d _x <1.8R _x・ V _x (9)

Within this range, a display having a high contrast ratio can be achieved by using the conventional active element for TN and the driving IC. The setting of d _x within the range of equation (9) is
It can be set appropriately depending on the relationship between the relative dielectric constant anisotropy Δε (= ε // − ε⊥) of the liquid crystal used and the elastic constant. Generally, a liquid crystal with a large Δε (Δε> 5) is used,
It is preferable to maximize d _x within a range where sufficient transparency is obtained at the maximum effective applied voltage.

As described above, in the active matrix liquid crystal display device using the liquid crystal resin composite which is in a transparent state when a voltage is applied and is in a scattering state when no electric field is applied, the formulas (1) to (4) and (6) to (8 ), Or (1), (2) and (5) to (8)
The liquid crystal display element satisfying all the conditions of (9) is a projection type with a high contrast ratio, a bright, and color-balanced by using the voltage range of formula (9), that is, the conventional active element for TN and the driving IC. It is possible to display a color video. Specifically, the contrast ratio is 100 or more and the transmittance when an electric field is applied is 70
% Or more, and the response time in gradation display of 100 msec or less is possible.

When the above-mentioned element is used as a reflection type, since light passes twice through the liquid crystal resin composite, the scattering property at the time of scattering increases. Therefore, within the range of the formula (8), d _x can be made thin and the maximum drive voltage determined by the formula (9) can be reduced.

Further, in order to improve the scattering property, it is effective to increase the volume fraction Φ of the operable liquid crystal of the liquid crystal resin composite, and Φ> 20% is preferable, and the higher scattering property is obtained. Is preferably Φ> 35%, more preferably Φ> 45%. On the other hand, if Φ is too large, the structural stability of the liquid crystal resin composite deteriorates, so Φ <70% is preferable.

In the liquid crystal display device of the present invention, in order to give the liquid crystal particles a specific aspect ratio, external pressure may be applied during or after the production of the liquid crystal resin composite. In addition, the shape of the liquid crystal particles can be changed by controlling the surface energy of the resin matrix, the elastic constant, the internal stress due to the contraction of the resin matrix during curing, and the like. Specifically, it is sufficient to control the uncured curable compound composition for the resin matrix, the curing temperature, the curing speed, etc., and experimentally determined so that the desired average particle size and its distribution, aspect ratio, etc. can be obtained. Just do it.

In the present invention, as described above, the major axis of the liquid crystal particles is oriented in a two-dimensional almost random direction on the cut surface in the direction perpendicular to the electrode surface of the liquid crystal resin composite. Needs to be done. Therefore, a manufacturing method in which the film is simply stretched in one axial direction is not preferable because the directions of the major axes are aligned in one direction.

In the liquid crystal display element of the present invention, the liquid crystal display element in which the refractive index of the resin matrix is made to match the ordinary refractive index (n _o ) of the liquid crystal used, when no voltage is applied, Due to the difference in the refractive index between the liquid crystal that is not aligned in parallel in a certain direction and the resin matrix, a scattering state (that is, a cloudy state) is exhibited.

Therefore, when used as a projection type display device as in the present invention, light is scattered in a portion without electrodes, and light is projected onto a projection screen without providing a light shielding film in a portion other than a pixel portion. It does not reach, so it looks black. As a result, in order to prevent light from leaking from the portion other than the pixel electrode, it is not necessary to shield the portion other than the pixel electrode with a light shielding film or the like, and there is also an advantage that the step of forming the light shielding film is unnecessary. Have.

A voltage is applied to a desired pixel. In the pixel portion to which this voltage is applied, the liquid crystal is aligned, and the ordinary state refractive index (n _o ) of the liquid crystal and the refractive index (n _p ) of the resin matrix match each other, thereby indicating a transmissive state. The light is transmitted, and it is displayed brightly on the projection screen.

By curing the device in such a state that a sufficiently high voltage is applied only to a specific portion during this curing step, that portion can be kept in a light transmitting state at all. If desired, such a normally permeable portion may be formed.

Further, the active matrix liquid crystal display device of the present invention can perform color display by providing a color filter. This color filter is
Three colors may be provided in one liquid crystal display element, one color may be provided in one liquid crystal display element, or three of these may be combined. This color filter may be provided on the electrode surface side of the substrate or may be provided on the outside. Further, color display may be performed by mixing a dye, a pigment or the like in the liquid crystal resin composite.

FIG. 1 is a schematic view of an example using a dichroic prism of a projection type active matrix liquid crystal display device of the present invention. In FIG. 1, 1 is a light source, 2 is a concave mirror, 3 is a condenser lens, 4 is a spectroscopic dichroic prism, and 5A, 5B, 5C and 5D are mirrors, and 1 to 5D constitute a color light source. 6A, 6B, 6C are active matrix liquid crystal display elements sandwiching a liquid crystal resin composite corresponding to each color, 7
Is a dichroic prism for synthesis, 8 is a projection lens, 9
Is an aperture for removing light other than the straight light, and 10 is a projection screen for projection. The projection optical system is composed of 7-9.

FIG. 2 is a schematic view of an example of the projection type active matrix liquid crystal display device of the present invention without using a dichroic prism. In FIG. 2, 11 is a light source, 12 is a concave mirror, 13 is a condenser lens, and 15A, 15B and 15C are dichroic mirrors, and 11 to 15C form a color light source. 16
A, 16B, 16C are active matrix liquid crystal display elements sandwiching a liquid crystal resin composite corresponding to each color, 18A, 18B,
18C is a projection lens for each color, 19A, 19B, 19
C is an aperture that is provided for each color and removes light other than the straight light, and 20 is a screen for projection. 18A ~ 19
C forms the projection optical system.

FIG. 3 is a sectional view of an active matrix liquid crystal display element used in the projection type active matrix liquid crystal display device of the present invention. In FIG. 3, 21 is an active matrix liquid crystal display element, 22 is a glass or plastic substrate for an active matrix substrate, and 23 is an ITO (In
₂ O ₃ -SnO ₂ ), a pixel electrode such as SnO ₂ , 24 is an active element such as a transistor, a diode, or a non-linear resistance element, 25 is glass for a counter electrode substrate, a substrate such as plastic, 26 is ITO,
A counter electrode made of SnO ₂ or the like, and 27 indicates a liquid crystal resin composite sandwiched between both substrates.

When a three-terminal element such as a TFT (thin film transistor) is used as the active element of the present invention, the counter electrode substrate may be provided with a solid electrode common to all pixels, but a two-terminal element such as an MIM element or a PIN diode. In the case of using, the counter electrode substrate is patterned in a stripe shape.

When a TFT is used as the active element, silicon is suitable as the semiconductor material.
In particular, since polycrystalline silicon is not photosensitive like amorphous silicon, it does not malfunction even if the light from the light source is not shielded by the light shielding film, which is preferable. When this polycrystalline silicon is used as a projection type liquid crystal display device as in the present invention, a strong light source for projection can be used and a bright display can be obtained.

Further, in the case of the conventional TN type liquid crystal display element, a light shielding film is often formed between the pixels in order to suppress the leakage of light from between the pixels, and at the same time, the light shielding film is formed on the active element portion at the same time. The light-shielding film can be formed, and forming the light-shielding film on the active element portion does not significantly affect the entire process. That is, even if polycrystalline silicon is used as the active element and the light shielding film is not formed in the active element portion,
If it is necessary to form a light-shielding film between pixels, the number of steps cannot be reduced.

On the other hand, in the present invention, a voltage is applied by using a liquid crystal resin composite in which the refractive index of the resin matrix is made to substantially match the ordinary refractive index (n _o ) of the liquid crystal used. Since light is scattered and black on the projection screen where the light is projected in the non-exposed portion, it is not necessary to form a light shielding film between pixels.

Therefore, when polycrystalline silicon is used as the active element, it is not necessary to form a light-shielding film on the active element portion or its light-shielding property may be weak, so that the step of forming the light-shielding film can be omitted. The strictness of the formed light-shielding film can be relaxed, and the productivity is improved.

Even when amorphous silicon is used,
If a light shielding film is formed on the semiconductor portion, it can be used. The electrodes are usually transparent electrodes, but when used as a reflective liquid crystal display device, they may be reflective electrodes of chromium, aluminum, or the like.

In the liquid crystal display device and the liquid crystal display device of the present invention, an infrared cut filter, an ultraviolet cut filter or the like may be laminated, characters or figures may be printed, or a plurality of liquid crystal display devices may be used. May be used.

Further, in the present invention, a protective plate such as a glass plate or a plastic plate may be laminated on the outside of the liquid crystal display element. As a result, even if the surface is pressed, the risk of damage is reduced, and safety is improved.

In the present invention, when a photocurable compound is used as the uncured curable compound which constitutes the above-mentioned liquid crystal resin composite, it is preferable to use a photocurable vinyl compound. Specifically, a photocurable acrylic compound is exemplified, and a compound containing an acrylic oligomer that is polymerized and cured by light irradiation is particularly preferable.

The liquid crystal used in the present invention is a nematic liquid crystal having a positive dielectric anisotropy, and the refractive index of the resin matrix is the same as that of the liquid crystal when voltage is applied or not applied. Such a liquid crystal may be used alone or as a composition, but it can be said that the use of the composition is advantageous for satisfying various performance requirements such as operating temperature range and operating voltage. In particular, the refractive index of the resin matrix, the use of liquid crystal, such as to match the ordinary refractive index of the liquid crystal (n _o) is preferred.

When the liquid crystal used in the liquid crystal resin composite is a photocurable compound, it is preferable that the photocurable compound is uniformly dissolved, and the cured product after photoexposure is not dissolved. Alternatively, it is considered to be difficult to dissolve, and when the composition is used, it is desirable that the solubility of each liquid crystal be as close as possible.

In the case of producing a liquid crystal resin composite, the active matrix substrate and the counter electrode substrate are arranged so that their electrode surfaces face each other like a conventional ordinary liquid crystal display element, and the periphery is sealed with a sealing material. Alternatively, the liquid mixture for uncured liquid crystal resin composite may be injected from the injection port to seal the injection port, or the uncured mixture of the curable compound and the liquid crystal may be supplied onto one of the substrates, The other substrate may be manufactured by stacking them so that the electrode surfaces face each other.

In the liquid crystal display device of the present invention, a dichroic dye, a simple dye or a pigment may be added to the liquid crystal, or a curable compound colored may be used.

In the present invention, liquid crystal is used as a solvent in the liquid crystal resin composite, and the photocurable compound is cured by photoexposure, so that it is not necessary to evaporate a simple solvent or water which is unnecessary at the time of curing. Therefore, since it can be cured in a closed system, the conventional manufacturing method of injecting into cells can be adopted as it is, it is highly reliable, and it has the effect of adhering two substrates with a photocurable compound. Will be more likely.

By using the liquid crystal resin composite as described above, there is a low risk of the upper and lower transparent electrodes being short-circuited, and it is necessary to strictly control the alignment and the substrate gap as in a normal TN type display element. In addition, a liquid crystal display element capable of controlling the transmission state and the scattering state can be manufactured with extremely high productivity.

When the substrate of this liquid crystal display element is plastic or thin glass, it is preferable to laminate a protective plate of plastic or glass on the outside for protection.

In the liquid crystal display device of the present invention, when a voltage is applied for driving, the liquid crystal resin composite material between the electrodes of the pixels is equal to or less than the maximum effective voltage of the above formula (9), and usually the above maximum effective voltage. It may be driven so as to be applied to.

The conventional light source, projection optical system, and projection screen can be used as the color light source, projection optical system, projection screen, etc. of the present invention. The active matrix liquid crystal of the present invention is provided between the color light source and the projection optical system. It suffices to dispose display elements to form a projection type active matrix liquid crystal display device. In this case, the projection optical system may combine the images of a plurality of active matrix liquid crystal display elements using the optical system as shown in FIG. 1 and then project the images. Alternatively, as shown in FIG. The images of the display elements may be individually projected on the projection screen and combined on the projection screen.

Further, although the color light source is also used by being dispersed from one light source in the above-mentioned example, it is also possible to separately provide light sources of a plurality of colors and make them incident on the active matrix liquid crystal display element. Light sources used for these color light sources include halogen lamps, metal halide lamps, xenon lamps, and the like, and a concave mirror, a condenser lens, and the like can be combined to improve light utilization efficiency. Further, a cooling system may be added to this, an infrared cut filter or an ultraviolet cut filter may be used in combination, or a channel display such as an LED may be added.

In particular, in the case of this projection type display, a device for reducing diffused light on the optical path, for example, 9 or 19 in FIGS.
Display contrast can be increased by installing apertures or spots as shown in A, 19B, and 19C.

That is, as a device for reducing diffused light, out of the light that has passed through the liquid crystal display element, the light that goes straight on with respect to the incident light (the light that passes through the portion where the pixel portion is in the transmission state) is extracted and the light that does not go straight ( It is preferable to use a liquid crystal resin composite that reduces the light scattered in the scattered state, because it improves the contrast ratio. In particular, it is preferable to reduce the diffused light, which is the light that does not travel straight, without reducing the light that travels straight.

The device for reducing the diffused light may be provided between the projection optical system and the projection screen as shown in FIGS. 1 and 2, or a plurality of projection optical systems may be included in the projection optical system. When the lens is formed of the above lens, it may be arranged between the lenses. The device for reducing the diffused light is not limited to the aperture and the spot as described above, and may be, for example, a small-area mirror arranged on the optical path.
Further, the focal length and aperture of the projection lens may be selected so as to remove diffused light without using a special aperture or the like.

A microlens system or the like can also be used. Specifically, by disposing a microlens array and a spot array in which fine holes are arrayed on the projection optical system side of the liquid crystal display element, unnecessary diffused light can be removed. In this case, the optical path length required for removing the diffused light can be extremely shortened, which has the advantage that the entire projection display device can be made compact. In order to shorten the optical path length, it is effective to incorporate a device for reducing diffused light in the projection optical system. In this case, the optical system becomes simpler and the size can be kept smaller than the case where the projection optical system and the device for reducing the diffused light are installed independently.

These optical systems can be combined with mirrors, dichroic mirrors, prisms, dichroic prisms, lenses, etc. to synthesize and color images, and also to color images by combining them with color filters.

The ratio of the straight-ahead component and the diffusive component reaching the projection screen can be controlled by the diameter of the spot, the mirror, etc. and the focal length of the lens, and can be set so that a desired display contrast and display brightness can be obtained. good.

When a device for reducing diffused light such as an aperture is used, in order to increase the display brightness, it is preferable that the light incident on the liquid crystal display element from the projection light source be more parallel, and for that purpose, the It is preferable to construct a projection light source by combining a light source having a brightness and as close as possible to a point light source, a concave mirror, a condenser lens, and the like.

Further, in the above description, the description has been made mainly of the transmission type, but even in the case of a reflection type projection type display device in which an electrode on one surface is used as a reflection electrode, for example, a small mirror is arranged instead of the spot. It is possible to extract only the necessary light.

[0141]

According to the present invention, a display having a high contrast ratio can be obtained, and when used in a projection display, light is transmitted in a transmissive-scattering liquid crystal display element in a transmissive state, and a projection screen is obtained. Is displayed brightly, light is scattered in the scattered state, and the projection screen is displayed darkly, so that a display with desired high brightness and high contrast ratio can be obtained.

In particular, according to the present invention, since it has the above-mentioned structure, the maximum effective applied voltage V applied to the liquid crystal resin composite can be set to 10 V or less, and high speed is achieved even in the halftone display. Responsiveness is obtained. Furthermore, the mystery is reduced and the image burn-in is reduced. By using the active elements and driving ICs used in the conventional active matrix liquid crystal display element for TN, it is possible to display moving images with fine gradation. You can easily.

Further, each color is well balanced, and beautiful gradation display of colors is possible without incorporating a special correction circuit in the drive circuit.

[0144]

EXAMPLES The present invention will be specifically described below with reference to examples. Example 1 60% chromium was applied onto a glass substrate (Corning 7059 substrate).
nm was evaporated and patterned to form a gate electrode. Subsequently, a silicon oxynitride film and an amorphous silicon film were deposited by a plasma CVD device. This was annealed using a laser and then patterned to obtain polycrystalline silicon.

Phosphorus-doped amorphous silicon and chromium were deposited on each of them by plasma CVD and a vapor deposition apparatus, and patterned so as to cover the polycrystalline silicon to form a first-layer source electrode and drain electrode. Furthermore, after depositing ITO, patterning was performed to form pixel electrodes. Then, chromium and aluminum were continuously vapor-deposited and patterned so as to connect the pixel electrode and the first-layer source and drain electrodes to obtain a second-layer source and drain electrodes. After that, again, a silicon oxynitride film was deposited by a plasma CVD apparatus as a protective film to prepare an active matrix substrate.

A counter electrode substrate made of the same glass substrate on which a solid ITO electrode is formed and an active matrix substrate manufactured previously are arranged so that their electrode surfaces face each other, and a spacer having a diameter of about 11.0 μm is internally provided. After spraying, the periphery of the cell was removed except for the injection port, and the cell was sealed with an epoxy-based sealing material to manufacture an empty cell with a substrate gap d _G of 11.0 μm.

Δn is about 0.24, Δε is about 16, and K33 is about 15.
(× 10 ^-12 N), viscosity of about 37 cSt nematic liquid crystal is dissolved in acrylate monomer, bifunctional urethane acrylate oligomer and photo-curing initiator, and the solution is injected into the cell, and the liquid crystal resin composite is cured by UV exposure. Then, an active matrix liquid crystal display device was prepared. Liquid crystal amount is 68
wt%, the interelectrode gap d _G is about 11 μm, the average particle size R _G of the liquid crystal is about 1.6 μm, the average aspect ratio A _G is 1.5, and the major axis direction of the liquid crystal particles is three-dimensionally random. there were.

Similarly, for red, d _R = 13.5 μm,
_{R R = 1.9μm, A R =} 1.5, d B = 9.5μm for the blue,
A cell with R _B = 1.5 μm and A _B = 1.5 was manufactured.

Using these elements, a projection type liquid crystal display device was prepared by combining a projection light source and a projection optical system as shown in FIG. When the drive voltage was driven by a video signal with a maximum value of 7 V and the image was projected on the screen, even in halftone display, a moving image display with good color balance without afterimage was obtained, and the contrast ratio on the screen was About 120
The burn-in was hardly seen when the image changed.

The response time (change in transmittance of 90% in black and white while operating RGB simultaneously) is 7 m → 0 V, 10 msec, 0 V →
It is 15msec at 7V, and 0V → saturated transmittance x 0.2 (about 16
%) Was 80 msec.

Comparative Example 1 Three liquid crystal display elements for green of Example 1 were prepared, and R
A projection type display device similar to that in Example 1 was configured by combining with a GB three-color light source.

The display obtained by this projection type display device is a reddish image as a whole, and this tendency is particularly remarkable in the display of halftones. When no voltage was applied to all three liquid crystal display elements, the projection screen became dark red instead of black. This is considered to be caused by the difference in the threshold voltage characteristics of the liquid crystal depending on RGB. Examining the applied voltage-transmittance characteristics for each RGB, R is the most transparent at the same applied voltage in the halftone region. The rate was high and B was the lowest.

Comparative Example 2 A projection type active matrix liquid crystal display device was produced as a TN type liquid crystal display device by injecting a normal nematic liquid crystal instead of the liquid crystal resin composite of Example 1.

This liquid crystal display element was combined with the projection light source and the projection optical system of Example 1 to form a projection type liquid crystal display device, and when driven in the same manner as in Example 1, the display brightness on the projection screen was As dark as about 1/3 of the case of Example 1,
A contrast ratio of about 100 was obtained. The response time is 25 msec from 5 V to 0 V, 30 msec from 0 V to 5 V,
At 0 V → saturated transmittance × 0.2 (about 6%), it was 160 msec.

Example 2, Comparative Examples 3 to 4 In the same manner as in Example 1, using the same liquid crystal, the average particle diameter R of the liquid crystal and the substrate gap d were changed to manufacture an active matrix liquid crystal display element.

The transmittance T _{8V of} the liquid crystal display element when a voltage of 8 V was applied, the contrast ratio CR on the screen when projected using the projection optical system, 0 V → saturated transmittance ×
The response time τ at 0.2 (about 16%) was measured. The average particle diameter R _X of the liquid crystal of the liquid crystal display element for each color and the substrate gap d _X
Was as follows.

In Example 2 for red, R _R = 1.8 μm, d _R = 10.5
μm, A _R = 1.8, R _G = 1.8 μm for green, d _G = 9.5 μm,
A _G = 1.6, the blue is _{R B = 1.8μm, d B =} 9.0μm, A B = 1.
It was 5.

For the red color of Comparative Example 3, R _R = 3.0 μm, d _R = 12.5
μm, A _R = 1.4, R _G = 2.6 μm for green, d _G = 11.0 μm,
A _G = 1.4, for blue R _B = 2.3 μm, d _B = 10.0 μm, A _B = 1.
It was 4.

R _R = 2.1 μm and d _R = 11.5 for the red color of Comparative Example 4.
μm, A _R = 1.2, for green R _G = 1.8 μm, d _G = 10.0 μm,
A _G = 1.2, the blue is _{R B = 1.6μm, d B =} 9.0μm, A B = 1.
It was 2.

The results are shown in Table 1. The color balance of each of Example 2 and Comparative Examples 3 and 4 was good.

[0161]

[Table 1]

Example 3 A projection type active matrix liquid crystal display device was prepared in substantially the same manner as in Example 1. However, the liquid crystal used for the liquid crystal display element of each color, the average particle diameter and the electrode substrate gap were set as follows.

For red, the liquid crystal Δn _R = about 0.29, Δε _R = about 1
6, K33 _R = about 16 (× 10 ^-12 N), viscosity η = about 52 cSt, R _R =
About 1.6 μm, d _R = 10.0 μm, A _R = about 1.5. The liquid crystal for green is Δn _G = about 0.24, Δε _G = about 16, K33 _G = about 15
(× 10 ^-12 N), viscosity η = approx. 37 cSt, R _G = approx. 1.6 μm, d _G
= 10.0 μm, A _G = about 1.4. The liquid crystal for blue is Δn _B = about 0.22, Δε _B = about 15, K33 _B = about 15
(× 10 ^-12 N), viscosity eta = about 34cSt, R _B = about 1.6 [mu] m, d _B
= 10.0 μm, A _B = about 1.4.

Using these elements, a projection type liquid crystal display device was prepared by combining a projection light source and a projection optical system as shown in FIG. When the maximum drive voltage was set to 8V in rms and it was driven by a video signal and an image was projected on the screen,
Even in the halftone display, a moving image display with good color balance without image sticking was obtained, and the contrast ratio on the screen was about 140. Response time is 20msec from 7V to 0V,
20 msec at 0 V → 7 V, 0 V → saturated transmittance × 0.2
(About 16%), it was 100 msec.

Example 4 A projection type active matrix liquid crystal display device was prepared in substantially the same manner as in Example 2. However, the liquid crystal used for the liquid crystal display element of each color, the average particle diameter and the electrode substrate gap were set as follows.

For red, the liquid crystal has Δn _R = about 0.29 and Δε _R = about 1.
6, K33 _R = about 15 (× 10 ^-12 N), viscosity η = about 52 cSt, R _R =
About 1.6 μm, d _R = 10.5 μm, A _R = about 1.8. The liquid crystal for green is Δn _G = about 0.24, Δε _G = about 16, K33 _G = about 15
(× 10 ^-12 N), viscosity η = approx. 37 cSt, R _G = approx. 1.6 μm, d _G
= 10.5 μm, A _G = about 1.8. The liquid crystal for blue is Δn _B = about 0.24, Δε _B = about 16, K33 _B = about 15
(× 10 ^-12 N), viscosity eta = about 37cSt, R _B = about 1.6 [mu] m, d _B
= 9.5 μm, A _B = about 1.8.

Using these elements, a projection type liquid crystal display device was obtained by combining a projection light source and a projection optical system as shown in FIG. When the maximum drive voltage was set to 8V in rms and it was driven by a video signal and an image was projected on the screen,
Even in the halftone display, a moving image display with good color balance without image sticking was obtained, and the contrast ratio on the screen was about 120. Response time is 20msec from 7V to 0V,
20 msec at 0 V → 7 V, 0 V → saturated transmittance × 0.2
(About 16%), it was 100 msec.

Example 5 The counter electrode was made of aluminum to be a reflection type element, and the electrode substrate gap was d _R = 6.0 μm for red and d _G for green.
= 5.0 .mu.m, outside which a d _B = 4.5 [mu] m for blue, in much the same way as in Example 1 to prepare a active matrix liquid crystal display device. However, the reflectance of the surface of the liquid crystal display element is about
It was set to 0.3%. Using these, a projection type active matrix liquid crystal display device was created.

The maximum drive voltage is set to an effective value of 5 V,
When it was driven by a video signal and an image was projected on the screen, even in halftone display, a moving image display with good color balance without afterimages and burn-in was obtained, and the contrast ratio on the screen was about 100. Response time is 5V → 0
It was 8 msec at V, 12 msec at 0 V → 5 V, and 80 msec at 0 V → saturated transmittance × 0.2 (about 16%).

Example 7 An empty cell having color filters of RGB three colors formed on the inner surface was formed. At this time, the gap of the red color filter portion was set to d _R = 11.5 μm, the gap of the green color filter portion was set to d _G = 10.5 μm, and the gap of the blue color filter portion was set to d _B = 10.0 μm.

A solution in which nematic liquid crystal was uniformly dissolved with an acrylate monomer, a urethane acrylate oligomer, and a photo-curing initiator was injected into this empty cell, and the liquid crystal resin composite was cured by exposure to ultraviolet rays to form an active matrix liquid crystal display device. Created. The used liquid crystal had Δn of about 0.24, Δε of about 16, K33 of about 15 (× 10 ^-12 N), and a viscosity of about 37 cSt. The average particle size of the liquid crystal is about 1.6μ.
m, and the average aspect ratio was about 1.6.

When a black absorber was placed on the background and this liquid crystal display device was driven by a video signal, fine color display with gradation without image sticking or image sticking was obtained. The contrast ratio of the liquid crystal display device was about 120. When this liquid crystal display element, a light source for projection, and a projection optical system are combined to form a projection type display device, and an image is projected on the screen,
A fine color display with no gradations and afterimages was obtained, and the contrast ratio on the screen was about 100.

[0173]

In the projection type active matrix liquid crystal display device of the present invention, as the liquid crystal material sandwiched between the active matrix substrate and the counter electrode substrate, a liquid crystal resin capable of electrically controlling the scattering state and the transmitting state. Since the liquid crystal display element sandwiching the composite is used, no polarizing plate is required, the light transmittance at the time of transmission can be significantly improved, and a bright projected image can be obtained.

Since the liquid crystal display element used in the liquid crystal display device of the present invention is excellent in transparency and scattering property, it is possible to use the conventional T
Even in the case where the driving IC for the N-type liquid crystal display element is used for driving, a display having a high contrast ratio and high brightness can be realized. In particular, by making the refractive index of the resin matrix approximately match the ordinary refractive index (n _o ) of the liquid crystal used, it has a high scattering property when no voltage is applied and a voltage is applied by an active element. It is possible to obtain high transparency, and it becomes possible to display a higher contrast ratio and higher brightness in the driving using the conventional driving IC for the TN type liquid crystal display element.

Further, in the present invention, since the characteristics of the liquid crystal display element are optimized for each color light source, a display having a good color balance can be obtained even in a halftone. Furthermore, the image sticking phenomenon based on hysteresis can be reduced even when gradation driving is performed.

Further, since it is not necessary to use a polarizing plate, there is an advantage that optical characteristics have little wavelength dependence and color correction of the light source is almost unnecessary. In addition, the liquid crystal display element used in the liquid crystal display device of the present invention can avoid the problems such as alignment treatment such as rubbing necessary for the TN type liquid crystal display element and the destruction of the active element due to the generation of static electricity. The manufacturing yield of can be greatly improved.

Further, since this liquid crystal resin composite is in the form of a film after being cured, problems such as short circuit between substrates due to pressurization of substrates and breakage of active elements due to movement of spacers are unlikely to occur.

Further, this liquid crystal resin composite has a specific resistance equivalent to that in the conventional TN mode, and it is not necessary to provide a large storage capacity for each pixel electrode as in the conventional DS mode, and the active element The design is easy, the ratio of the effective pixel electrode area can be easily increased, and the power consumption of the liquid crystal display element can be kept low.

Further, the manufacturing process is easy because the manufacturing process of the conventional liquid crystal display device of the TN mode can be carried out only by removing the alignment film forming process.

Further, the liquid crystal display element using this liquid crystal resin composite has a feature that the response time is short, and it is easy to display a moving image. Further, since the electro-optical characteristic (voltage-transmittance) of this liquid crystal display element is a comparatively gentle characteristic as compared with the TN mode liquid crystal display element,
It is also easy to apply to gradation display.

Further, in the liquid crystal display element of the present invention, the refractive index of the resin matrix is made to substantially match the ordinary refractive index (n _o ) of the liquid crystal used, so that light is scattered in the portion where no voltage is applied. Therefore, even if the portion other than the pixel is not shielded by the light shielding film, light does not leak at the time of projection and it is not necessary to shield the gap between the adjacent pixels.

Therefore, in particular, by using an active element made of polycrystalline silicon as the active element, it is possible to use a high-luminance projection light source without a light-shielding film in the active element portion or with a light-shielding film with low strictness. A high-brightness projection type liquid crystal display device can be easily obtained. Further, in this case, the light-shielding film may not be provided at all, or the light-shielding film having low strictness may be used, and the production process can be simplified.

In addition to the above, the present invention can be applied in various ways within the range of not impairing the effects of the present invention.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a basic configuration of a projection type active matrix liquid crystal display device of the present invention.

FIG. 2 is a schematic diagram showing a basic configuration of another projection type active matrix liquid crystal display device of the present invention.

FIG. 3 is a sectional view showing a basic configuration of an active matrix liquid crystal display element of the present invention.

FIG. 4 is a perspective view illustrating the randomness of the liquid crystal particles of the present invention in the direction of the major axis.

FIG. 5 is a cross-sectional view illustrating randomness in the direction of the long axis of the liquid crystal particles of the present invention.

[Explanation of symbols]

1, 11: Light source 2, 12: Concave mirror 6A, 6B, 6C, 16A, 16B, 16C: Active matrix liquid crystal display element 8, 18A, 18B, 18C: Projection lens 10, 20: Projection screen 21: Liquid crystal display element 22, 25: Substrate 23: Pixel electrode 24: Active element 26: Counter electrode 27: Liquid crystal resin composite

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Satoshi Niiyama 1150 Hazawa-machi, Kanagawa-ku, Yokohama, Kanagawa Prefecture Asahi Glass Co., Ltd. Central Research Laboratory (72) Inventor Yoshiharu Oi 1150, Hazawa-machi, Kanagawa-ku, Yokohama Kanagawa Company Central Research Institute

Claims (8)

[Claims] 1. A projection type active system having a plurality of color light sources, a plurality of active matrix liquid crystal display elements on which light from the respective color light sources is incident, and a projection optical system for synthetically projecting light emitted from the active matrix liquid crystal display elements. In a matrix liquid crystal display device, a nematic liquid crystal having a positive dielectric anisotropy is a resin between an active matrix substrate in which an active matrix liquid crystal display element has an active element for each pixel electrode and a counter electrode substrate having a counter electrode. By sandwiching a liquid crystal resin composite, which is dispersed and held in the matrix, and the refractive index of the resin matrix is almost the same as the refractive index of the liquid crystal used when the voltage is applied or not applied. an active matrix liquid crystal display device comprising, an average of each color liquid crystal which is dispersed and held in a resin matrix particle diameter R _x ( m), the aspect ratio A _x, each color of the inter-electrode gap d _x (μm), the dielectric anisotropy [Delta] [epsilon] _x of the liquid crystal used, the elastic constant K33 _x (10 ^-12 N), viscosity eta _x (cSt), The refractive index anisotropy Δn _x and the dominant wavelength λ _x (μm) of each color are 3 (K33 _x / η _x ) ^0.5 > R _x / A _x > 0.7 (K33 _x / Δε _x ) ^0.5 (1) 1.3 < If the relationship of A _x <2.3 (2) is satisfied and at least one set of active matrix liquid crystal display elements is i ≠ j, Δn _i · R _i / (A _i · λ _i ) ≈Δn _j · R _j / ( A _j・ λ _j ) (3) and satisfy the relationship of d _i / R _i ≈d _j / R _j (4), or Δn _i・ d _i ² / λ _i ≈Δn _j・ d _j ² / λ _j (5) is satisfied, and the direction of the major axis of the liquid crystal particles is two-dimensionally almost random in the cross section perpendicular to the electrode surface of the liquid crystal resin composite. Characteristic projection type active matrix liquid crystal display device. 2. The color light source according to claim 1, which is a color light source of RGB three colors, wherein x satisfies the expressions (1) and (2) for all three RGB colors, and Δn _R · R _R / (A _R · λ _R ) ≈Δn _G・ R _G / (A _G・ λ _G ) ≈Δn _B・ R _B / (A _B・ λ _B ) (3A) and d _R / R _R ≈d _G / R _G ≈d _B / R Satisfy the relationship of _B (4A) or satisfy the relationship of Δn _R・ d _R ² / λ _R ≈ Δn _G・ d _G ² / λ _G ≈ Δn _G・ d _G ² / λ _G (5A) A projection type active matrix liquid crystal display device characterized by the above. 3. The refractive index anisotropy Δ of the liquid crystal used in the active matrix liquid crystal display device according to claim 1 or 2.
A projection type active matrix liquid crystal display device, characterized in that when n _x is λ _i > λ _j , the relationship of Δn _j ≦ Δn _i is satisfied. In any one of claims 4] claims 1-3, 0.2 <a projection type active matrix liquid crystal display device which satisfies the relationship of _{R x · Δn x <0.7 (} 6). 5. A projection type active matrix liquid crystal display according to any one of claims 1 to 4, which satisfies a relationship of Δn _x ² _· Δε _x / (K33 _x · η _x )> 0.0011 (7). apparatus. 6. The liquid crystal resin composite according to claim 1, wherein the maximum effective applied voltage V _x (V) is 4R _x <A _x · d _x <15R _x (8) 0.8R. A projection type active matrix liquid crystal display device characterized by satisfying a relationship of _x · V _x <A _x · d _x <1.8R _x · V _x (9). 7. A nematic liquid crystal having a positive dielectric anisotropy between an active matrix substrate having color filters of three colors of RGB, each pixel electrode having an active element, and a counter electrode substrate having a counter electrode. Is dispersed and held in the resin matrix, and the liquid crystal resin composite is sandwiched so that the refractive index of the resin matrix substantially matches the refractive index of the liquid crystal used when voltage is applied or not applied. In an active matrix liquid crystal display device formed by
Average particle size R of liquid crystal dispersed and held in resin matrix
(μm), its aspect ratio A, the gap between electrodes of each color d _x (
μm), relative permittivity anisotropy of liquid crystal Δε, elastic constant K33 (10
^-12 N), viscosity η (cSt), refractive index anisotropy Δn, and dominant wavelength λ _x (μm) of each color are 3 (K33 / η) ^0.5 > R / A> 0.7 (K33 / Δε) ^0.5 ( 1B) 1.3 <a <2.3 ( 2B) 0.2 < satisfy the relationship of R · Δn <0.7 (6B) Δn 2 · Δε / (K33 · η)> 0.0011 (7B) 4R <a · d G <15R (8B) However, in the relationship with at least two colors of RGB, i ≠ j, the relationship of d _i ² / λ _i ≈d _j ² / λ _j (5B) is satisfied, and the direction perpendicular to the electrode surface of the liquid crystal resin composite is satisfied. The projection type active matrix liquid crystal display device, wherein the major axis direction of the liquid crystal particles is two-dimensionally substantially random on the cut surface. 8. A projection type active matrix liquid crystal display device comprising the active matrix liquid crystal display device according to claim 7 in combination with a projection light source and a projection optical system.