JPH05203943A - Liquid crystal panel and liquid crystal projector using this panel - Google Patents

Abstract

PURPOSE:To provide the liquid crystal panel of a high-brightness and high- contrast display and the liquid crystal projector. CONSTITUTION:A layer 15 having rugged sectional shapes is formed on the surfaces of at least either of picture element electrodes 14 and counter electrodes 22 of the liquid crystal panel facing a liquid crystal layer and high-polymer dispersed liquid crystals 23 are used for the liquid crystals. The layer 15 having the rugged sectional shapes acts as a diffraction grating if the recessed parts and projecting parts of the layer 15 having the rugged sectional shapes are formed to have regular periodicity. The scattering performance of the liquid crystal layer is improved even if the recessed parts and projecting parts of the layer 15 having the rugged sectional shapes are so formed as not to have the regular periodicity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal projection device for mainly enlarging and projecting an image displayed on a small liquid crystal panel on a screen, and a liquid crystal panel mainly used for the liquid crystal projection device.

[0002]

2. Description of the Related Art Since a liquid crystal display device has many features such as light weight and thin shape, research and development are actively conducted. However, there are many problems such as difficulty in increasing the screen size. So in recent years
A liquid crystal projection television, which obtains a large-screen display image by enlarging and projecting a display image on a small liquid crystal panel using a projection lens or the like, has suddenly attracted attention. At present, twisted nematic (hereinafter referred to as TN) liquid crystal panels that utilize the optical rotation property of liquid crystals are used in commercialized liquid crystal projection televisions.

First, a general liquid crystal panel will be described. FIG. 25 is a plan view of the liquid crystal panel. (Fig. 2
In 5), 251 is a glass substrate (hereinafter referred to as an array substrate) on which a thin film transistor (hereinafter referred to as a TFT) as a switching element is formed, and 252 is an IT substrate.
A substrate on which a transparent electrode made of O or the like is formed (hereinafter, referred to as a counter substrate) 256 is a drive IC (hereinafter, referred to as a drive IC) for applying a signal for controlling ON / OFF of a TFT connected to a gate signal line on the array substrate 251. , A gate drive IC), 255 is a drive IC for applying a data signal to a source signal line on the array substrate 251 (hereinafter referred to as a source drive IC), 253 is a polarizing film, 254
Is a sealing resin for sealing the liquid crystal. After that,
Those denoted by the same reference numerals have the same contents, the same configurations, or similar ones.

FIG. 26 (a) is a plan view of one pixel portion of a conventional liquid crystal panel. Further, (FIG. 26 (b)) is a cross-sectional view taken along line DD ′ of (FIG. 26 (a)). However,
In the drawings, portions unnecessary for description are omitted for ease of description, and the drawings are drawn as models. The above also applies to the following drawings.

In FIGS. 26A and 26B, reference numeral 12 is a source signal line, one end of which is the source drive IC 2
Connected to 55. Reference numeral 11 is a gate signal line, one end of which is connected to the gate drive IC 256.
16 is a first electrode, that is, a pixel electrode 14 made of ITO
Is an array substrate on which is formed. In (Fig. 27),
21 is a counter substrate, 271 is a layer made of TN liquid crystal (hereinafter,
It is called a TN liquid crystal layer), and its film thickness is around 5 μm. 32 is a black matrix. An alignment film (not shown) made of an organic material such as polyimide resin is formed on the counter electrode 22 and the pixel electrode 14. The size of one pixel is about 500 μm to 30 μm.

FIG. 29 shows a conventional liquid crystal panel, TN.
The explanatory view of operation of a liquid crystal panel is shown. In FIG. 29, 291 is a polarizing plate, 292 is a polarization direction, 293 is a transparent electrode, 294 is a liquid crystal molecule, 295 is a signal source, and 296 is a switch. As shown in FIG. 29, the incident light rotates 90 degrees in the off state, and transmits without rotating in the on state. Therefore, if the polarization directions of the two polarizing plates 291 are orthogonal to each other, light is transmitted in the off state and is shielded in the on state. However, if the polarization directions are parallel to each other, the opposite is true. As described above, the TN liquid crystal panel modulates light to display an image.

A conventional liquid crystal projection device will be described below with reference to the drawings. FIG. 28 is a configuration diagram of a conventional liquid crystal projection device. In FIG. 28, 281 is a condensing optical system, 282 is an infrared cut mirror that transmits infrared rays, 283a is a blue light reflection dichroic mirror (hereinafter referred to as BDM), and 283b is a green light reflection dichroic mirror (hereinafter referred to as GDM). 283c is a red light reflecting dichroic mirror (hereinafter referred to as RDM), 2
84a, 284b, 284c, 286a, 286b, 2
86c is a polarizing plate, 285a, 285b and 285c are transmissive conventional TN liquid crystal panels, 287a, 287b and 28.
7c is a projection lens system. It should be noted that components unnecessary for the description, such as a field lens, are omitted from the drawings.

The operation of the conventional liquid crystal projector will be described below with reference to FIG. 28. First, the white light emitted from the condensing optical system 281 is reflected by the BDM 283a as blue light (hereinafter referred to as B light), and this B light is incident on the polarizing plate 284a. The light transmitted through the BDM 283a is reflected by the GDM 283b as green light (hereinafter referred to as G light), is reflected by the polarizing plate 284b, and is reflected by the RDM 283c as red light (hereinafter referred to as R light).
It is incident on 84c. The polarizing plate transmits only one of the longitudinal wave component and the transverse wave component of each color light, aligns the polarization direction of the light, and irradiates each liquid crystal panel. At this time, 50% or more of the light is absorbed by the polarizing plate, and the brightness of the transmitted light becomes half or less at the maximum.

Each liquid crystal panel modulates the transmitted light according to a video signal. The modulated light passes through the polarizing plates 286a, 286b, 286c according to the degree of modulation, enters the projection lens systems 287a, 287b, 287c, and is enlarged and projected on a screen (not shown) by the lens system. It

[0010]

As is clear from the above description, in a liquid crystal panel using TN liquid crystal, it is necessary to make linearly polarized light incident on the liquid crystal panel. Therefore, it is necessary to dispose polarizing plates before and after the liquid crystal panel. The above-mentioned polarizing plate theoretically absorbs 50% or more of light. Therefore, as a conventional problem, there is a problem that only a low-luminance screen can be obtained when enlarged projection is performed on the screen.

As a prior art of a liquid crystal panel and a liquid crystal projection device which does not use a polarizing plate, an element in which a nematic liquid crystal and a diffraction grating are combined has been proposed in Japanese Patent Publication No. 53-3928 and the like. It is difficult to orient the liquid crystal molecules if the pitch is fine and the height is uneven.

In order to solve the above problems, the present invention uses a polymer dispersed liquid crystal. A liquid crystal panel using polymer-dispersed liquid crystal does not use a polarizing plate, and thus the light utilization efficiency can be made very high. Further, since orientation control is unnecessary, even if the substrate surface has irregularities such as a diffraction grating, there is no problem at all.

The polymer dispersed liquid crystal will be briefly described below. Polymer dispersed liquid crystals are roughly classified into two types depending on the dispersion state of liquid crystals and polymers. One is a type in which liquid crystals in the form of water droplets are dispersed in a polymer. The liquid crystal exists in the polymer in a discontinuous state. Hereinafter, such a liquid crystal will be referred to as a PDLC, and a liquid crystal panel using the liquid crystal will be referred to as a PD liquid crystal panel. The other is a type that has a structure in which a polymer network is stretched around the liquid crystal layer. It looks like a sponge containing liquid crystal. The liquid crystal does not form a water drop but continuously exists. Hereinafter, such a liquid crystal will be referred to as a PNLC, and a liquid crystal panel using the liquid crystal will be referred to as a PN liquid crystal panel. In order to display an image with the above-mentioned two types of liquid crystal panels, light scattering and transmission are controlled.

The PD liquid crystal panel utilizes the property that the refractive index is different in the direction in which the liquid crystal is aligned. When no voltage is applied, each water droplet liquid crystal is oriented in an irregular direction. In this state, a difference in refractive index occurs between the polymer and the liquid crystal, and incident light is scattered. When a voltage is applied here, the alignment directions of the liquid crystal are aligned. If the refractive index when the liquid crystal is oriented in a certain direction is matched with the refractive index of the polymer in advance, incident light is transmitted without being scattered.

On the other hand, the PN liquid crystal panel uses the irregularity itself of the alignment of liquid crystal molecules. Irregular orientation,
That is, the incident light is scattered when no voltage is applied. On the other hand, when a voltage is applied and the arrangement state is made regular, light is transmitted. The above description of the movement of the liquid crystal of the PD liquid crystal panel and the PN liquid crystal panel is merely a model idea. Although the present invention is not limited to one of the PD liquid crystal panel and the PN liquid crystal panel, the PD liquid crystal panel will be described as an example for ease of explanation.
Further, the PD liquid crystal panel and the PN liquid crystal panel are collectively called a polymer dispersed liquid crystal panel. Further, the liquid containing the liquid crystal to be injected into the polymer dispersed liquid crystal panel is generically called a liquid crystal solution or a resin, and the state in which the resin component in the liquid crystal solution is polymerized and cured is called a polymer.

The polymer matrix in the polymer-dispersed liquid crystal layer which becomes the liquid crystal layer of such a dispersion type liquid crystal display device may be either thermoplastic resin or thermosetting resin as long as it is basically transparent. However, UV curable resins are the most convenient and have good performance and are often used in general. The reason is that the conventional manufacturing method of the TN mode liquid crystal panel can be directly applied. As a conventional liquid crystal panel manufacturing method, first, a predetermined electrode pattern is formed in advance on the upper and lower substrates, and the two substrates are stacked so that the electrodes face each other. At this time, two substrates are fixed with an epoxy resin sealant in a state where a spacer having a predetermined size and a uniform particle size is sandwiched between the substrates so that the gap between the two substrates can be maintained. Next, a manufacturing method in which a liquid crystal is injected into the empty cell thus obtained is often used.

In order to manufacture a dispersion type liquid crystal panel by applying this manufacturing method, if an ultraviolet curable resin, especially an acrylic resin as an example thereof, is used as the material of the polymer matrix, before injection. Is monomer or
It exists as a precursor having a relatively low viscosity such as an oligomer and an oligomer, and the blend with the liquid crystal has sufficient fluidity to be injected at room temperature. Therefore, a dispersion type liquid crystal panel can be easily prepared by applying a conventional liquid crystal panel manufacturing method and using a method of irradiating light after injection and proceeding a curing reaction to form a polymer dispersed liquid crystal layer.

When the panel is irradiated with ultraviolet rays after the injection, only the resin undergoes a polymerization reaction to become a polymer, and only the liquid crystal undergoes phase separation. When the amount of liquid crystal is smaller than that of the resin component, independent particle-shaped liquid crystal droplets are formed. On the other hand, when the amount of liquid crystal is large, the polymer matrix is present in the liquid crystal material in the form of particles or networks, and the liquid crystal is formed so as to form a continuous layer. At this time, if the particle diameter of the liquid crystal droplets or the pore diameter of the polymer network is uniform to some extent and the size is not in the range of 0.1 μm to several μm, the light scattering performance is poor and the contrast ratio cannot be increased. For this purpose, the material must be one that can be cured in a relatively short time, and an ultraviolet curable resin is desirable.

The operation of the polymer dispersed liquid crystal panel will be briefly described with reference to FIGS. 30 (a) and 30 (b). (Fig. 30
(A) (b) is explanatory drawing of operation | movement of a polymer dispersion liquid crystal panel. In FIGS. 30A and 30B, 301 is an array substrate, 302 is a pixel electrode, 303 is a counter electrode, 30
Reference numeral 4 is a water droplet liquid crystal, 305 is a polymer, and 306 is a counter substrate. A TFT or the like is connected to the pixel electrode 302, and TF
When T is turned on / off, a voltage is applied to the pixel electrode, the liquid crystal alignment direction on the pixel electrode is changed, and light is modulated.
As shown in FIG. 30A, when no voltage is applied, the water droplet liquid crystals 304 are oriented in irregular directions. In this state, a difference in refractive index occurs between the polymer 305 and the liquid crystal, and incident light is scattered. Here (Fig. 30
As shown in (b), when a voltage is applied to the pixel electrode, the liquid crystal is aligned. If the refractive index when the liquid crystal is aligned in a certain direction is matched with the refractive index of the polymer in advance, the incident light is emitted from the array substrate 301 without being scattered.

As described above, since the polymer-dispersed liquid crystal panel does not require a polarizing plate, the light utilization efficiency is high and a display image with extremely high brightness can be obtained. However, if the above liquid crystal is used for a liquid crystal panel, there are the following problems.

One is peeling of the polymer dispersed liquid crystal layer from the counter electrode or the pixel electrode. This occurs because the degree of adhesion between the electrode made of ITO or the like and the polymer dispersed liquid crystal layer is low. In a liquid crystal projection television, a temperature of 50 to 60 degrees is applied to a liquid crystal panel when a lamp as a light source is turned on,
On the contrary, when the lamp is turned off, the temperature is 10 to 30 degrees at room temperature. Therefore, when the power of the liquid crystal projection television is turned on and off, the liquid crystal panel is exposed to the severe condition as in the heat shock test. The above-mentioned peeling occurs due to this heat shock state or the like.

The other one is that the scattering characteristics are poor. In order to put this polymer-dispersed liquid crystal panel into practical use as a device, it must be driven at a low voltage and have a sufficient contrast ratio. To obtain a particularly good display, the contrast ratio should be 3
0: 1 or more, preferably 100: 1 or more for projection type. In order to increase the contrast ratio, it is necessary to improve the light scattering characteristics. Although perfect diffusion can be considered as one target of the scattering action, the contrast ratio CR in perfect diffusion can be calculated by CR = 1 / sin ² σ (Dew
ey. Proc. ofSID. P138.1977).
However, σ is a converging angle (half angle). In order to increase the contrast ratio, it is necessary to improve the light scattering characteristics.
Increasing the thickness of the polymer-dispersed liquid crystal layer improves the light scattering performance, but raises the driving voltage and makes it difficult to drive the TFT. At present, the light-scattering characteristics of polymer-dispersed liquid crystal panels have not reached the perfect scattering state, which is an ideal scattering state.

In particular, when used as a projection type display, the F-number of a concave mirror condensing optical system using a metal halide lamp which is generally used at present and a projection optical system matching with this is 4 to 5, which is a high level at present. The contrast ratio when using the molecular dispersion liquid crystal panel is insufficient at about 50: 1.

An object of the present invention is to provide a liquid crystal panel and a liquid crystal projection device with high brightness display and high contrast.

[0025]

In order to achieve the above object, according to the present invention, at least one of a first substrate and a second substrate facing each other having a light transmitting property, and the first and second substrates. An electrode layer formed on opposite surfaces of the
And a polymer-dispersed liquid crystal layer sandwiched between a second substrate and a layer having an uneven cross-sectional shape formed on the surface of at least one of the first and second substrates on which the electrodes are formed. The liquid crystal panel is constructed from the and.

The liquid crystal panel, the light generating means, and the light generated by the light generating means are guided to the liquid crystal panel.
A liquid crystal projection device is constituted by the optical element parts and the second optical element parts that project the light modulated by the liquid crystal panel.

More specifically, a layer having an uneven cross-sectional shape is formed of a light transmissive material having a refractive index that is the same as or near the refractive index n _{p of the} polymer. The refractive index of the light transmissive material is n _t
And Further, the ordinary light refractive index of the liquid crystal is n _o and the extraordinary light refractive index is n _e, and n _p = n _o . In the off state, the refractive index n _x of the liquid crystal layer as a whole is a refractive index obtained by macroscopically combining the polymer refractive index n _p and the liquid crystal refractive indices n _o and n _e . Since the refractive indexes n _t and n _x of the layer having the uneven cross-sectional shape are different, a difference in refractive index occurs between the two. When the concave portions and the convex portions of the layer having the uneven cross-sectional shape are formed with regular periodicity, the light incident on the liquid crystal panel is diffracted, and the component that goes straight is reduced. In other words, the layer having the uneven cross-sectional shape acts as a diffraction grating. This means that if the polymer-dispersed liquid crystal layer is in the scattering state, the apparent scattering performance will be high. If the polymer-dispersed liquid crystal layer is not in the scattering state or the scattering performance is extremely weak, only the diffraction effect is used. In the ON state, the liquid crystal molecules are aligned in a fixed direction, and n _p = n _o = n _x . Therefore, n _p = n _t = n _x . This means that there is no difference between the refractive index n _x of the liquid crystal layer and the refractive index n _t of the layer having the uneven cross-sectional shape. Therefore, since the diffraction grating is extinguished, the incident light goes straight on. The larger the difference in refractive index between the liquid crystal layer and the polymer, and the difference between the liquid crystal layer and the diffraction grating, the greater the scattering performance and diffraction efficiency.

On the other hand, even when the concave and convex portions of the layer having the uneven cross-sectional shape do not have regular periodicity,
For example, even in the case of a structure having only convex portions or only concave portions such as microlenses, it is possible to reduce straight traveling light by the effect of refraction and to apparently improve scattering performance.

If the dielectric constant of the layer having an uneven cross-sectional shape is different from that of the polymer-dispersed liquid crystal layer, the lines of electric force in the liquid crystal panel bend, and the refractive index of the liquid crystal layer temporarily increases. Become. This increases the difference in the refractive index between the liquid crystal and the polymer and enhances the scattering performance.

[0030]

The diffraction grating is formed of a light transmissive material having a refractive index equal to or near the refractive index n _{p of the} polymer. The refractive index of the light transmissive material is n _t . Further, the ordinary light refractive index of the liquid crystal is n _o and the extraordinary light refractive index is n _e, and n _p = n _o . (Fig. 3
0 (a)), in the off state, the refractive index n _x of the liquid crystal layer as a whole is a refractive index obtained by macroscopically combining the refractive index n _{p of the} polymer and the refractive index n _o · n _{e of the} liquid crystal. Show. Since the refractive indexes n _t and n _x of the diffraction grating are different, a difference in refractive index occurs between them. The light that has entered the liquid crystal panel is diffracted by the diffraction grating, and the amount of components that go straight is reduced. In other words, the diffraction grating acts as a diffraction grating. When the ON state as shown in (FIG. 30 (b)), the liquid crystal molecules are aligned in a certain direction, and _{n p = n o = n a} . Thus, the _{n p = n t = n a} . This means that there is no difference between the refractive index n _a of the liquid crystal layer and the refractive index n _t of the diffraction grating. Therefore, the same state as when the diffraction grating is not formed is obtained, and the incident light goes straight on. Further, the formation of the diffraction grating means that unevenness is formed on the counter electrode or the pixel electrode. This enhances the adhesion between the liquid crystal layer and the electrodes.
If a light transmissive material is selected as the material of the diffraction grating, the aperture ratio of the pixel does not decrease.

[0031]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The liquid crystal panel of the present invention will be described below with reference to the drawings. (FIG. 1A) is a plan view of one pixel of the liquid crystal panel of the present invention. However, in order to make the drawing easy to see (FIG. 1A), the counter electrode substrate and the like are omitted. In FIGS. 1A and 1B, reference numeral 15 is a layer formed on the array substrate 16 in a stripe shape and having an uneven cross-sectional shape. (Fig. 1 (b))
It is sectional drawing in the AA 'line of (a)). In addition, (FIG. 2) is a structure in which the counter substrate 2 is formed on the array substrate 16 of (FIG. 1A).
1 is a cross-sectional view when 1 is attached and a polymer dispersed liquid crystal 23 is injected between the substrates. The layer having the uneven cross-sectional shape may be formed on the counter substrate 21. In FIG. 2, the gate signal line 11, the source signal line 12 and the TFT 13 are
Although the black matrix 32 for shielding the above is omitted, it may be provided on the counter substrate 21. In the first embodiment of the present invention, the protrusions and recesses of the layer 15 having an uneven cross-sectional shape are formed with regular periodicity. That is, the layer 15 having an uneven cross-sectional shape functions as a diffraction grating. (Hereinafter referred to as a diffraction grating) The drawings are drawn as models. For example, the number, width, and shape of the diffraction gratings also correspond to this. That is, it is not limited to the number and width.
Specifically, the pixel size is 200 to 30 μm, and the pitch P of the diffraction grating is 15 to 1 μm. Therefore, the number of diffraction gratings is larger than that normally shown (FIG. 1).

In (FIG. 1) and (FIG. 2), the diffraction grating 15 is formed only in the convex portion, and the pixel electrode 14 is exposed in the concave portion. When a layer is also formed in the concave portion of the diffraction grating 15 as shown in (FIG. 3), a voltage drop occurs in this portion and it becomes difficult to apply a voltage to the liquid crystal, but the desired effect is the same. .. Usually, the pixel electrode 14 and the counter electrode 22 are formed of ITO, which is an oxide of indium and tin and has good transparency.

The counter electrode 22 may be a reflective electrode 42 made of a metal having a high reflectance such as Al or Cr. (Figure 4)
A cross-sectional view of a reflective liquid crystal panel is shown in FIG. The diffraction grating 15 may be formed on the pixel electrode 14, but is preferably formed on the reflective electrode 42 as shown in FIG.
In the case of a reflection type liquid crystal panel, the incident light ray is the liquid crystal layer 23.
Is reflected by the reflection electrode 42, passes through the liquid crystal layer 23 again, and is emitted. Therefore, the light path is twice the thickness of the liquid crystal layer, and if the liquid crystal layer thickness is the same, the scattering characteristic is improved as compared with the transmissive liquid crystal panel. In other words, in order to obtain the same scattering characteristics, the liquid crystal layer thickness of about half is enough. Similarly, the height d of the diffraction grating 15 is half the height of the transmissive liquid crystal panel, and the same diffraction efficiency can be obtained. Although the counter electrode is the reflective electrode in (FIG. 4), the same effect can be obtained by using the pixel electrode 14 as the reflective electrode. Further, as shown in FIG. 5, a structure in which the reflective electrode 42 is formed on the upper layer of the pixel electrode 14 via the insulating layer 51 improves the aperture ratio, which is still more preferable.

The material of the diffraction grating has optical transparency,
Further, it is preferably optically isotropic. Examples of such materials include inorganic substances such as SiOx, SiNx, TaOx, glass-based substances, and organic substances such as polyimide and acrylic resins. The material is selected according to the refractive index of the polymer dispersed liquid crystal layer 23. Regarding the refractive index of each material, the ordinary refractive index n _o of the liquid crystal is 1.45 to 1.55, the extraordinary refractive index n _e of the liquid crystal is 1.65 to 1.80, and the refractive index n _{p of the} polymer is 1.45. The one of 1.55 is often used. In many cases, n _p = n _o is set.

The dielectric constant of the diffraction grating is preferably larger than that in the direction perpendicular to the alignment vector of the liquid crystal used and smaller than that in the parallel direction. It is preferably matched with the dielectric constant in the direction parallel to the alignment vector of the liquid crystal used.
By doing so, a sufficient electric field and electric field direction can be applied to the liquid crystal layer above the diffraction grating.

The liquid crystal material used in the liquid crystal panel of the present invention is preferably a nematic liquid crystal, a smectic liquid crystal or a cholesteric liquid crystal, and may be a single or two or more kinds of liquid crystal compounds or a mixture containing a substance other than the liquid crystal compounds. Good. Among the liquid crystal materials described above, a cyanobiphenyl nematic liquid crystal having a relatively large difference between the extraordinary refractive index n _e and the ordinary optical refractive index n _o is most preferable. A transparent polymer is preferable as the polymer matrix material, and the polymer may be any of a thermoplastic resin, a thermosetting resin, and a photocurable resin, but the ease of the manufacturing process, the separation from the liquid crystal phase, etc. From this point, it is preferable to use an ultraviolet curable resin. As a specific example, an ultraviolet-curable acrylic resin is exemplified, and a resin containing an acrylic monomer or an acrylic oligomer that is polymerized and cured by ultraviolet irradiation is particularly preferable.

As such a polymer-forming monomer,
2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, neopentyl glycol acrylate, hexanediol diacrylate, diethylene glycol diacrylate, tripropylene glycol diacrylate, polyethylene glycol diacrylate, trimethylolpropane triacrylate, pentaerythritol acrylate and the like.

Examples of the oligomer or prepolymer include polyester acrylate, epoxy acrylate and polyurethane acrylate.

A polymerization initiator may be used to accelerate the polymerization, and as an example, 2-hydroxy-2-
Methyl-1-phenylpropan-1-one (“Darocur 1173” manufactured by Merck & Co., Inc.), 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-
On (Merck's "Darocur 1116"), 1-vidroxycyclohexyl phenyl ketone (Ciba-Geigy's "Irgacure 184"), benzyl methyl ketal (Ciba-Geigy's "Irgacure 651"), etc. are mentioned.

In addition, a chain transfer agent, a photosensitizer, a dye, a cross-linking agent and the like can be appropriately used in combination as optional components.

After injecting a liquid or viscous material in which a liquid crystal material is uniformly dissolved in this ultraviolet curable compound between two substrates, ultraviolet irradiation is carried out to cure only the ultraviolet curable compound. At this time, only the liquid crystal material is phase separated to form a polymer dispersed liquid crystal layer.

The proportion of the liquid crystal material in the polymer dispersed liquid crystal layer is not specified here, but is generally 20% by weight to 90% by weight.
The degree is good, preferably about 50 to 70% by weight. If it is 20% by weight or less, the amount of liquid crystal droplets is small and the scattering effect is poor. On the other hand, when it is 90% by weight or more, the proportion of the interface becomes small and the light scattering decreases. The structure of the polymer-dispersed liquid crystal layer changes depending on the liquid crystal fraction. When the content is about 50% by weight or less, the liquid crystal droplets exist as independent droplets, and when the content is 50% by weight or more, the polymer and the liquid crystal are in a continuous phase. ..

Refractive index of the liquid crystal layer 23 when the liquid crystal is in the off state
n_xIs generally (2n_o+ N_e) / 3. Positive invitation
When a liquid crystal with electric anisotropy is used, the liquid in the ON state
The refractive index of the crystal layer 23 is n_oBecomes Therefore, the liquid crystal is off.
Diffraction grating appears when in ON state and diffraction grating when in ON state
In order to eliminate the_t= N_o= N _p
Alternatively, it may be set to a value in the vicinity thereof. Tsuma
Therefore, when the liquid crystal is in the off state, the refractive index n of the liquid crystal layer_xIs (2n_o
+ N_e) / 3, so n_t≠ n_xAnd the diffraction grating 15
Then, a refractive index difference Δn occurs in the liquid crystal layer 23. LCD is on
When, the refractive index of the liquid crystal layer is n_oTherefore, n_o= N_pTosu
When n_t= N_pBecomes That is, the diffraction grating 15 and the liquid crystal layer 2
There is no difference in refractive index in 3. Refractive index n of diffraction grating_tAnd poly
Refractive index n of Mar_pRefractive index difference should be within 0.1
Desirable, furthermore, the material within 0.1 should be selected.
It Conversely, when the liquid crystal is in the on state, a diffraction grating appears,
In order to eliminate the diffraction grating in the full state, the diffraction grating 15
Refractive index n of_tIs (2n_o+ N _e) / 3 if it matches
Good. When a liquid crystal having a negative dielectric anisotropy is used,
The refractive index of the liquid crystal layer 23 in the ON state is n_eTherefore,
When the liquid crystal is in the off state, a diffraction grating appears,
At this time, in order to extinguish the diffraction grating, the refractive index n of the diffraction grating is
_t= N_e= N_pAnd need to.

From the above examination, it is considered that as the material for forming the diffraction grating, SiO ₂ is suitable as the current inorganic material because it is easy to form and process in the process. The refractive index of SiO ₂ is usually about 1.45 to 1.50. As a forming method, SiO ₂ may be vapor-deposited, a pattern mask may be formed, and etching may be performed. Further, it is optimal to use the same transparent polymer as that used for the liquid crystal layer 23 as the organic material. As a method of forming a diffraction grating using the above materials, it is possible to apply it on a substrate with a roll quarter, a spinner or the like, and polymerize only a necessary portion using a pattern mask. In addition, spin coating a photosensitive resin consisting of polymer + dopant on the substrate,
There is also a method of performing dry development by exposing through a pattern mask and then sublimating the dopant by heating under reduced pressure.

The pitch p and height d of the diffraction grating 15 differ considerably depending on the wavelength λ of the light to be modulated, the refractive index of the liquid crystal layer 23, the light directivity of the optical system and the required diffraction efficiency. In the state where no voltage is applied, the emitted light beam is affected by scattering and diffraction. For example, as shown in FIG. 1, the diffraction grating 15
Is a rectangular cross-section, the diffraction angle θ and the efficiency η ₀ of the _0th- order diffracted light are given as follows.

Sin θ = mλ / p (where m is the diffraction order) η ₀ = 0.5 * (1 + cos δ) where δ = 2πΔnd / λ Therefore, the pitch p and the height d are the directivity of the optical system and the diffraction. It should be determined by the angle θ and the wavelength λ. However, it often depends on process conditions for forming the diffraction grating. The pitch t is approximately 2 μm to 60 μm, among which 4 μm to 20 μm is optimal. In the process, the shape of the diffraction grating is a sine curve like that shown in FIG.
Alternatively, it is often a triangular wave shape as shown in (FIG. 7) or a sawtooth shape as shown in (FIG. 8), but it may be designed according to a desired diffraction grating and diffraction direction. There is no problem in its effect.

The height d largely depends on the diffraction efficiency. The difference between the refractive index n _t of the diffraction grating and the refractive index n _x of the liquid crystal layer, that is, Δ
When n is 0.1, the height d is 3 to 5 μm when the 0th order light is set to 0 when the diffraction grating has a rectangular cross section.
is necessary. However, normally, it is not necessary to completely set the 0th-order light to 0, and the height d may be 2 to 3 μm if the diffraction efficiency is 40 to 70%. Even if the diffraction efficiency is 40 to 70%, a sufficiently practical value can be obtained for the contrast when the projection television is constructed.

The height d and the pitch p of the diffraction grating are limited because they are shown below. (FIG. 9) is a diffraction grating 1
The lines of electric force in the vicinity of 5 are shown as a model. Now, for ease of explanation, it is assumed that the lines of electric force originate from the counter electrode 22 and end at the pixel electrode 14. A line of electric force A emitted from the counter electrode 22 between the diffraction gratings 15 is the counter electrode substrate 2
It extends in the direction perpendicular to 1, that is, the normal direction. However, the electric force line B near the diffraction grating 15 extends along the convex portion of the diffraction grating 15, that is, the slope, and an angle of θ with the normal direction is generated. This is due to the dielectric constant ε _e of the liquid crystal 23 and the dielectric constant ε _{k of the} diffraction grating 15.
It happens because there is a big difference. Dielectric constant ε of normal liquid crystal 23
_e is different depending on whether the voltage is applied or not, but is about 1
5 to 25. On the other hand, the dielectric constant of the diffraction grating 15 is 4 to 6
Is. That is, the lines of electric force are easily transmitted through the liquid crystal and are less likely to be transmitted through the diffraction grating 15.

The liquid crystal molecules are aligned along the lines of electric force when an electric field above a certain level is applied. Further, the liquid crystal has a different refractive index depending on the orientation direction. Liquid crystal parallel to the normal of the counter electrode substrate 21, i.e. the liquid crystal refractive index ordinary refractive index when θ = 0 n _o
Becomes On the other hand, when θ is 90 degrees, the refractive index is theoretically (n _o + n _e ) / 2. When θ is in the range of 0 to 90 degrees, the refractive index in the intermediate state is shown. Therefore, the liquid crystal molecules 91
a refractive index from a theta = 0 becomes n _o. Liquid crystal molecule 9
The refractive index of 1b is an intermediate value between n _o and (n _o + n _e ) / 2.

In the liquid crystal panel of the present invention, when the voltage is applied
Sometimes the refractive index of the liquid crystal 23 between the diffraction grating 15 and the diffraction grating 1
The refractive index of 5 is made to match and the diffraction effect is eliminated.
It Diffraction occurs when the liquid crystal molecules 71b are oriented at an angle of θ.
The liquid crystal 23 between the gratings 15 and the diffraction grating 15 have the same refractive index.
Absent. However, when θ is small, the refractive index of the liquid crystal molecules 91b
Is almost n_oCan be regarded as The amount of polymer is the refraction of the liquid crystal layer 23
Assuming that it does not contribute to the refractive index, the refractive index of liquid crystal molecules is θ = 0.
When n_o, Θ = 90 degrees (n_o+ N_e) / 2
However, the refractive index between them is a non-linear curve with respect to θ.
Changes. Specifically, it has a sine curve shape.
That is, when θ is 0 to 20 degrees, the refractive index of liquid crystal molecules is n._oTomi
The refractive index of liquid crystal molecules is 70-90 degrees.
(N_o+ N _e) / 2 value. Because
And when θ can be regarded as small n_oCan be regarded as therefore,
The tilt angle of the diffraction grating 15 is at least 45 degrees, that is, θ =
45 degrees, preferably 60 degrees or more, that is, θ = 3
0 degree, more preferably the inclination angle is 70 degrees or more, that is, θ
= 20 degrees or less is recommended.

From this fact, the height of the diffraction grating and the pitch p
The ratio d / p is preferably 1/3 or more. Further, d / p is preferably 1/2 or more. As a specific design value, when d = 3 to 4 μm, the diffraction grating is formed in the range of p = 5 to 8 μm. At this time, the diffraction angle θ becomes 5 to 7 degrees, and when the liquid crystal projection device is configured, a projection lens having a value of around F4.0 can be used.

The thickness of the liquid crystal layer is preferably in the range of 5 μm to 25 μm, and more preferably in the range of 8 μm to 15 μm. This means that when the film thickness is 20 μm or more, the light incident on the liquid crystal panel is in a completely diffused state and the scattering characteristics are good, but a high voltage is required for driving. On the other hand, the film thickness is 8 μm
If the voltage is less than the above value, it can be driven at a low voltage, but the scattering characteristics will be poor.

Although the diffraction grating 15 described above is formed in a stripe shape, as shown in (FIG. 10) and (FIG. 11), the diffraction grating 15 is fixed on the pixel electrode 14 in a block shape or a column shape. It may be a so-called two-dimensional diffraction grating formed at intervals. (Fig. 1
0) shows a plan view of one pixel of the liquid crystal panel of the present invention. In the embodiments described so far, since the diffraction grating 15 is formed in a stripe shape, the incident light diffracts only in one dimension. If the diffraction grating is formed as in the present invention,
The incident light is two-dimensionally diffracted. (Figure 11) is (Figure 1
It is sectional drawing of the panel comprised using the board | substrate shown in 0).

The liquid crystal projection apparatus of the present invention will be described below with reference to the drawings. FIG. 12 is a configuration diagram of an embodiment of the liquid crystal projection device of the present invention. However, components that are unnecessary for the description are omitted. In FIG. 12, 12
A condenser optical system 1 has a concave mirror and a metal halide lamp of 250 W as a light generating means inside.
Moreover, the concave mirror is configured to reflect only visible light. Further, an ultraviolet cut filter is arranged at the emission end of the condensing optical system 121. Reference numeral 122 is an infrared cut mirror that transmits infrared light and reflects only visible light.
However, the infrared cut mirror 122 is the condensing optical system 121.
It goes without saying that it may be placed inside the. Also,
123a is BDM, 123b is GDM, and 123c is RD.
It is M. It is needless to say that the arrangement of the BDM 123a to the RDM 123c is not limited to the above order, and the last RDM 123c may be replaced with a total reflection mirror.

Reference numerals 124a, 124b and 124c are the liquid crystal panels of the present invention. It should be noted that the height d of the diffraction grating formed in the liquid crystal panel 124c that modulates the R light in the liquid crystal panel is less than the height d of the diffraction grating of the other liquid crystal panels.
It is formed 2 μm to 1.0 μm higher. This is because the degree of diffraction depends on the wavelength of the light to be modulated. Further, if necessary, the height of the diffraction grating of the blue light modulating liquid crystal panel 124a is also formed to be 0.2 μm to 1.0 μm lower than that for green. The liquid crystal panel 124c that modulates the R light is configured to have a larger diameter of water-drop-shaped liquid crystal particles or a larger liquid crystal film thickness than other liquid crystal panels. This is because the longer the wavelength of light, the lower the scattering characteristics. The particle size of the water-drop liquid crystal can be controlled by controlling the ultraviolet light during polymerization or by changing the material used. The liquid crystal film thickness can be adjusted by changing the bead diameter in the liquid crystal layer. 125a, 125b, 125c, 1
27a, 127b and 127c are lenses, 126a,
Reference numerals 126b and 126c are apertures as diaphragms. Note that 125, 126, and 127 form a projection lens system. Further, the aperture 126 is an FNo. Obviously it is not necessary when is large.

Regarding the drive circuit of the liquid crystal panel (see FIG.
2 (b)). The video signal is driven by a drive circuit for driving signals Sa for the red (R), green (G) and blue (B) panels,
Converted to Sb and Sc. The drive signal Sa is the liquid crystal panel 1
The drive signal Sb is applied to the gate signal line and the source signal line of the liquid crystal panel 124b, the drive signal Sb is applied to the gate signal line and the source signal line of the liquid crystal panel 124b, and the drive signal Sc is applied to the gate signal line and the source signal line of the liquid crystal panel 124c. Hereinafter, although the same figure is used for (FIG. 17 (b)) and FIG. 20 (b), the operation is the same, and thus the description thereof is omitted.

The operation of the liquid crystal projection device of the present invention will be described below. Since the modulation systems for red (R), green (G), and blue (B) light have almost the same operation, the modulation system for B light will be described as an example. First, white light is emitted from the condensing optical system 121, and the B light component of the white light is reflected by the BDM 123a. This B light is incident on the polymer dispersed liquid crystal panel 124a. The scattered light is blocked by the aperture 126a, and conversely, parallel light or light within a predetermined angle passes through the aperture 126a. The modulated light is projected onto a screen (not shown) by the projection lens 127a.
Is enlarged and projected. As described above, the B light component of the image is uniformly displayed on the screen. Similarly, the polymer dispersed liquid crystal panel 124b modulates the G light component light, and the polymer dispersed liquid crystal panel 124c modulates the R light component light so that a color image is displayed on the screen.

The arrangement and the like of the projection lens system are as follows. First, the polymer dispersed liquid crystal panel 12 of the liquid crystal display device.
4 is arranged so that the distance L between the lens 125 and the lens 125 and the distance between the lens 125 and the aperture 126 are substantially equal. The projection lens system as described above plays a role of transmitting parallel rays that have passed through each liquid crystal panel and blocking light that has been scattered by each liquid crystal panel. As a result, high-contrast full-color display can be realized on the screen. The contrast is improved by reducing the aperture diameter D of the aperture. However, the image brightness on the screen is reduced. (Figure 12)
Can be thought of as a simple Schlieren optical system.

The film thickness of the liquid crystal layer of the liquid crystal panel of the present invention is 1
In the case of 0 μm to 15 μm, the converging angle θ of the lens needs to be 8 degrees or less in all angles. Of these, about 6 degrees is optimal, and at that time, the contrast is 100: 1 at the center of the screen, and when projected on a 40-inch screen by a rear system TV, the screen gain is 200 ft or more, and C
It was possible to obtain a screen brightness equal to or higher than that of the RT projection television. A short arc lamp is used. More specifically, the configuration diagram of (FIG. 12) is shown as an example (FIG. 1).
3) is shown in a perspective view and the like. In FIG. 13, 121 is a condensing optical system, 123 is a dichroic mirror,
Reference numeral 124 is the liquid crystal panel of the present invention, 131 and 132 are lenses, 133 is a mirror, and 134a, 134b and 134.
Reference numeral c is a projection lens system having a projection lens or an aperture.

In the liquid crystal panel of the present invention, incident light is scattered, diffracted and emitted. However, as shown in (FIG. 1) to (FIG. 9), when the diffraction grating 15 is formed in a stripe shape, the intensity distribution of the light on the wavefront in the direction parallel to the diffraction grating 15 does not diffract at all and scatters. Is only affected by. In this way, there is a difference in the scattering (diffraction) effect depending on the vibration direction of each light. Therefore, we placed an anamorphic lens before the light enters the panel,
By making a difference in the spread angle of the light in advance and then making the light incident on the panel, the different direction of the scattering performance is corrected. Alternatively / and apertures 126a, 126b,
The correction can also be performed by opening the aperture ratio of 126c into a shape that is different depending on the direction of the scattering characteristics of the panel.

In addition to the optical system shown in FIG. 12, the optical system may be of a reflective type as shown in FIG. In FIG. 14, 124 is a liquid crystal panel of the present invention. Light emitted from a light emitting source 121 such as xenon is condensed on a mirror 142 by a lens 141. The condensed light enters the lens 143, and the light illuminates the liquid crystal panel 124. The liquid crystal panel 124 modulates the light, scatters the light in the portion for displaying black, and reflects the incident light as it is in the portion for displaying white. The scattered or reflected light enters the lens 143 again. The scattered light is reflected by the mirror 142.
The light is blocked by the light blocking plate 126. The straight traveling light is transmitted between the light shielding plate 126 and the mirror 142 and projected on a screen (not shown) to display an image. In addition, in the drawing, as in the case of the above-described configuration diagram and the like, components unnecessary for the description are omitted. Therefore, in actual construction, a field lens and a projection lens suitable for the projection distance and the projection angle should be arranged.

Note that the projection lens system is not limited to this in (FIG. 12) and (FIG. 14), and for example, a central shield type optical system in which parallel light components are shielded by a light shield and scattered light is projected on the screen. It goes without saying that a system may be used.

The structure of the liquid crystal panel of the present invention is TFT.
However, the present invention is not limited to this, and is also effective in a liquid crystal display device that uses a two-terminal element such as a diode as a switching element.

Further, in FIG. 12 or FIG. 14, the light is made incident from the counter substrate side, but the invention is not limited to this, and the same effect can be obtained by making the light incident from the array substrate. Is clear. As mentioned above,
The liquid crystal panel and the liquid crystal projection device of the present invention do not depend on the incident direction of light.

Although the liquid crystal projection apparatus according to the present invention is described as a rear type liquid crystal projection type television, the present invention is not limited to this, and a front type liquid crystal projection type television for projecting an image on a reflection type screen. But needless to say. Further, in the liquid crystal projection device of the present embodiment, the color separation is performed by the dichroic mirror, but the invention is not limited to this. For example, an absorption type color filter may be used to perform the color separation.

Further, in the liquid crystal projection device of the present embodiment, one projection lens system is provided for each of the R, G and B light modulation systems, but the invention is not limited to this, and, for example, a mirror or the like may be provided. It goes without saying that the display images modulated by the liquid crystal panel may be combined into one and then made incident on one projection lens system for projection. Furthermore, although the liquid crystal panel that modulates each of R, G, and B lights is provided, the present invention is not limited to this. For example, it may be a single panel projection device in which a mosaic color filter is attached to one liquid crystal panel and the pixels of the panel are projected.

The second embodiment of the liquid crystal panel and the liquid crystal projection apparatus using the same according to the present invention will be described below, but the description will be limited to the difference from the first embodiment. Therefore, matters not described are the same as those in the first embodiment. The above also applies to the other embodiments described below. In the second embodiment of the present invention, the scattering effect of the polymer dispersed liquid crystal layer is made as small as possible, and the diffraction effect is mainly used.

In order to minimize the scattering performance of the polymer-dispersed liquid crystal layer, the film thickness d of the liquid crystal layer should be reduced, or the average particle size of the liquid crystal droplets or the average voids of the polymer dispersed and held by the polymer should be reduced. The distance r may be reduced or the ratio of the liquid crystal material in the polymer dispersed liquid crystal layer may be increased. As preferable conditions, the thickness of the liquid crystal layer is preferably 5 μm or less, r is preferably 1 μm or less, and the liquid crystal ratio is preferably 90% by weight or more, and at least one of these conditions may be satisfied. If the scattering performance is high, the effect of diffraction will be alleviated. The particle size of the water-drop liquid crystal can be controlled by controlling the ultraviolet light during polymerization or by changing the material used. The liquid crystal film thickness can be adjusted by changing the bead diameter in the liquid crystal layer. When the film thickness becomes thin, it becomes possible to drive the liquid crystal panel at a low voltage.

Therefore, it can be considered that the structure of the liquid crystal panel in the second embodiment of the present invention is almost the same as the panel structure shown in the first embodiment. However, the liquid crystal layer 23 satisfies at least one of the above three conditions. The diffraction efficiency can be changed by changing the refractive index of the liquid crystal layer by applying an electric field between the pixel electrode 16 and the counter electrode 22. This is as described in the first embodiment. When the thickness of the liquid crystal layer is thin, the cross-sectional view of the liquid crystal panel in the second embodiment of the present invention can have the structure shown in FIG.

In the embodiment shown in FIG. 15, the diffraction grating 1
The height of 5 and the height of the liquid crystal layer 23 are substantially the same. Others are the same as those in the first embodiment. According to the present invention, the counter electrode 22 and the pixel electrode 14 can be arranged under the diffraction grating 15 even if the material forming the diffraction grating 15 has a low dielectric constant. This is because there is no liquid crystal layer 23 in the diffraction grating 15 and it is not necessary to drive it. In addition, since the diffraction grating is arranged on the electrodes in the first embodiment, the direction of the lines of electric force in the liquid crystal layer 23 in which a voltage drop occurs becomes extremely complicated. However, if the liquid crystal layer is formed only in the concave portion of the diffraction grating as in the present invention, the above problem does not occur, and in the off state, a difference in refractive index occurs between the diffraction grating 51 and the liquid crystal layer 23, and the diffraction is caused. When the effect occurs, there is no difference in the ON state, and the diffraction effect disappears and display is possible.

Also, in the second embodiment, all the applications of the other configurations described in the first embodiment are applicable.

A liquid crystal projection device according to a second embodiment of the present invention will be described below with reference to the drawings. (FIG. 16) is a schematic view conceptually showing the principle structure of a liquid crystal projection device of the present invention using a schlieren optical system. In FIG. 16, the liquid crystal panel 124 of the present invention is used as a light valve, and the schlieren input mask 1 having a large number of openings.
Schlieren lens 16 between 61 and output mask 162
3 is installed and the image of the input mask 161 is output to the output mask 16
A schlieren optical system having a structure for forming an image on the screen 2 is constructed, and the liquid crystal panel 124 is arranged in the schlieren optical system. In the present invention, the schlieren lens 163
Although it is placed between the input mask 161 and the liquid crystal panel 124, it may be placed between the liquid crystal panel 124 and the output mask 162. The concave mirror 166 is not used because it is used to increase the light utilization efficiency. Light from the light source 164 is passed through the input mask 161 and the schlieren lens 163 of the schlieren optical system to the liquid crystal panel 124.
The image is projected onto the screen 165 via the projection lens 127 as light that is incident on the screen 165 and leaks from the opening pattern of the output mask 162 due to the diffraction of light according to the projection image on the liquid crystal panel 124.

FIG. 17 is a block diagram of an embodiment of the liquid crystal projection device of the present invention. However, components that are unnecessary for the description are omitted. In FIG. 17, reference numeral 121 denotes a condensing optical system, which has a concave mirror inside and a light generating means 250.
It has a W metal halide lamp. Moreover, the concave mirror is configured to reflect only visible light. Further, an ultraviolet cut filter is arranged at the emission end of the condensing optical system 121. Reference numeral 122 is an infrared cut mirror that transmits infrared light and reflects only visible light. However, it goes without saying that the infrared cut mirror 122 may be arranged inside the condensing optical system 121. Also, 123a is B
DM, 123b is GDM, and 123c is RDM. The arrangement of the BDM 123a to the RDM 123c is not limited to the above order, and the last RDM 12
It goes without saying that 3c may be replaced by a total reflection mirror.

Reference numerals 124a, 124b and 124c are the liquid crystal panels of the present invention. It should be noted that the height d of the diffraction grating formed in the liquid crystal panel 124c that modulates the R light in the liquid crystal panel is less than the height d of the diffraction grating of the other liquid crystal panels.
It is formed 2 μm to 1.0 μm higher. This is because the degree of diffraction depends on the wavelength of the light to be modulated. Further, if necessary, the height of the diffraction grating of the liquid crystal panel 96a for blue light modulation is 0.2 μm to 1.0 μm lower than that for green. 161a, 161b and 161c are input masks, 1
62a, 162b and 162c are output masks, 163
Reference numerals a, 163b and 163c are Schlieren lenses. Note that 161, 162 and 163 form a Schlieren optical system. Also 127a, 127b, 12
Reference numeral 7c is a projection lens.

The thickness of the liquid crystal layer of the liquid crystal panel of the present invention is 3
When the pitch and height of the diffraction grating are 4 to 5 μm and 3 to 6 μm, respectively, the converging angle θ of the lens needs to be 8 degrees or less in all angles. Around 6 degrees is the most suitable, and the contrast ratio is 1 at the center of the screen.
It was 00: 1, and when the image was projected on a 40-inch screen by the rear type liquid crystal projection device, an image quality comparable to that of the CRT projection device could be obtained. The lamp used was a metal halide lamp with a short arc length, but a xenon lamp may also be used.

The operation of the liquid crystal projection device of the present invention will be described below. Since the modulation systems for red (R), green (G), and blue (B) light have almost the same operation, the modulation system for B light will be described as an example. First, white light is emitted from the condensing optical system 121, and the B light component of the white light is reflected by the BDM 123a. The B light passes through the input mask 161a and the schlieren lens 163a and enters the diffraction grating polymer dispersed liquid crystal panel 124a.
The diffraction grating polymer dispersed liquid crystal panel controls the refractive index of the liquid crystal layer by a signal applied to the pixel electrode and modulates light. When the refractive index difference between the liquid crystal layer and the diffraction grating disappears, the incident light goes straight, and the straight light is blocked by the output mask 162a,
On the contrary, if there is a difference in refractive index between the liquid crystal layer and the diffraction grating, the incident light is diffracted and passes through the output mask 162a. The modulated light is enlarged and projected on a screen (not shown) by the projection lens 127a. As described above, the B light component of the image is displayed on the screen. Similarly, the polymer dispersed liquid crystal panel 124b modulates the light of the G light component, and the polymer dispersed liquid crystal panel 124c modulates the light of the R light component,
A color image is displayed on the screen.

FIG. 18 shows a liquid crystal projection device having another structure of the second embodiment of the present invention. Light source 164 and input mask 1
The fly-eye lens 181 is arranged between the 61. The fly-eye lens 181 is designed and arranged so that a light source image is formed in the opening of the input mask 161, and serves to form a minute light source array. Further, it is desirable to provide a field lens array (not shown) near the input mask. The other structure is the second embodiment of the present invention shown in FIG.
Is the same as Liquid crystal panel 124 as a light valve
Is the diffraction grating polymer-dispersed liquid crystal panel used in Example 2. FIG. 19 shows a plan view of the fly-eye lens 181. The fly-eye lens 181 is an aggregate of an array of minute lenses, and each minute lens 191 is configured to correspond to each one of the openings of the input mask 161. As a result, the light emitted from the light source 164 that passes through one minute lens 191 passes through one opening of the input mask 161, passes through the schlieren lens 163, the liquid crystal panel 124, and the output mask 162, and the projection lens 12
Projected by 7. Considering this optical path as one optical system, the F number is large and the contrast is high, and since it is regarded as one system in which a large number of this optical system are assembled, the brightness is not lowered. In other words, the entire surface of the pupil is used when the liquid crystal panel 124 is in the transmissive state, and the pupil area is effectively reduced by the output mask 162 during diffraction.

The liquid crystal projection apparatus of the present invention will be described below with reference to the drawings. FIG. 20 is a configuration diagram of an embodiment of the liquid crystal projection device of the present invention. However, components that are unnecessary for the description are omitted. In FIG. 20, 12
A condenser optical system 1 has a concave mirror and a metal halide lamp of 250 W as a light generating means inside.
Moreover, the concave mirror is configured to reflect only visible light. Further, an ultraviolet cut filter is arranged at the emission end of the condensing optical system 121. Reference numeral 122 is an infrared cut mirror that transmits infrared light and reflects only visible light.
However, the infrared cut mirror 122 is the condensing optical system 121.
It goes without saying that it may be placed inside the. Also,
123a is BDM, 123b is GDM, and 123c is RD.
It is M. It is needless to say that the arrangement of the BDM 123a to the RDM 123c is not limited to the above order, and the last RDM 123c may be replaced with a total reflection mirror.

Reference numerals 124a, 124b and 124c are liquid crystal panels. The height d of the diffraction grating formed in the liquid crystal panel 124c that modulates the R light in the liquid crystal panel is 0.2 μm or more than the height d of the diffraction grating of the other liquid crystal panel.
It is formed 1.0 μm higher. This is because the degree of diffraction depends on the wavelength of the modulated light. Further, if necessary, the height of the diffraction grating of the blue light modulating liquid crystal panel 124a is also formed to be 0.2 μm to 1.0 μm lower than that for green.
161a, 161b and 161c are input masks, 162
a, 162b and 162c are output masks, 163a,
163b and 163c are Schlieren lenses.
181a, 181b and 181c are fly-eye lenses and 127a, 127b and 127c are projection lenses.

Fly-eye lens 181 and input mask 1
61 may be integrated into one and installed between the condensing optical system 121 and the dichroic mirror 123a. In addition, the schlieren lens 163 includes the liquid crystal panel 124 and the output mask 16.
It may be installed between the two.

In the liquid crystal projection device of the present invention, when the thickness of the liquid crystal layer of the liquid crystal panel is 10 μm to 15 μm, the contrast ratio is 100 at the center of the screen even if the converging angle θ of the projection lens is about 6 degrees in all angles. 1 or more, 40 on rear TV
When projected on an inch screen, the image quality was comparable to that of a CRT projection TV. The lamp was a 250 W metal halide lamp with an arc length of 7 mm, and sufficient characteristics were obtained without using a short arc lamp.

The operation of the liquid crystal projection device of the present invention will be described below. Since the respective modulation systems for red (R), green (G), and blue (B) light have almost the same operation, the B light modulation system will be described as an example. First, white light is emitted from the condensing optical system 121, and the B light component of the white light is reflected by the BDM 123a. The B light passes through the fly-eye lens 181a, the input mask 161a, and the schlieren lens 163a and enters the liquid crystal panel 124a. The liquid crystal panel controls the diffracted state of the incident light by the signal applied to the pixel electrode and modulates the light. The diffracted light is blocked by the output mask 162a, and conversely, parallel light or light within a predetermined angle passes through the output mask 162a. The modulated light is enlarged and projected on a screen (not shown) by the projection lens 127a. As described above, the B light component of the image is displayed on the screen. Similarly, the polymer dispersed liquid crystal panel 124b modulates the light of the G light component, and
The polymer dispersed liquid crystal panel 124c modulates the light of the R light component, and a color image is displayed on the screen.

The third aspect of the present invention will now be described with reference to the drawings.
The liquid crystal panel of the embodiment will be described. (Fig. 21
21A is a plan view of a counter substrate which constitutes the liquid crystal panel of the present invention, and FIG. 21B shows A of FIG. 21A.
It is a sectional view taken along the line A '. (Figure 22) is (Figure 21)
The array substrate 16 is attached to the counter substrate 21 of (a),
FIG. 3 is a diagram showing a state in which a polymer dispersed liquid crystal layer 23 is sandwiched between both substrates. A transparent electrode 22 made of ITO is formed on the counter substrate 21, and the source signal line 1 is formed on the counter electrode 22.
2. A black matrix 32 is formed on the gate signal line (not shown) and the TFT (not shown). Examples of the material for forming the black matrix 32 include a metal material such as aluminum, chromium, and chromium oxide, or a material in which carbon is mixed in an acrylic resin, and it is preferable to form chromium matrix 32 in terms of patterning accuracy and processability. The black matrix 32 need not be formed when it does not affect the image quality. On the other hand, a convex protrusion (microlens) 211 made of a transparent material is formed on the counter electrode 22. The constituent material of the protrusion is SiO 2 as the inorganic substance.
Examples of the organic substance include x, SiNx, TaOx, and glass substances, and examples of the organic substance include polyimide and ultraviolet curing resin.

As with the first and second embodiments, it is preferable to select the material in accordance with the refractive index np of the polymer of the polymer dispersed liquid crystal layer 23. The refractive index na of the liquid crystal layer 26 when the liquid crystal is in the off state is generally represented by about (2no + ne) / 3. N when on
a = no. Therefore, in order to cause the microlens 211 to appear when the liquid crystal is in the off state and to disappear the microlens when the liquid crystal is in the on state, the microlens 211 is set to have a refractive index n.
It suffices that d = np or a value near it. That is, when the liquid crystal is off, the refractive index na of the liquid crystal layer is
Is (2no + ne) / 3, nd ≠ na, and a difference in refractive index occurs between the microlens 211 and the liquid crystal layer 26.
On the contrary, when the liquid crystal is in the ON state, the refractive index na of the liquid crystal layer is no, so that if no = np, then nd = np. That is, there is no difference in refractive index between the microlens 211 and the liquid crystal layer 23. The refractive index difference between the refractive index nd in the microlens and the refractive index np of the polymer is preferably within 0.2,
Furthermore, materials within 0.1 should be selected.

Next, an example of the method of manufacturing the liquid crystal panel of the present invention will be briefly described. It is assumed that SiO2 is used as the material for forming the microlens 211. First, a transparent substance such as SiO2 is deposited on the counter substrate 21. The film thickness to be vapor-deposited is set by the height of the microlens 211 to be formed. Next, a metal substance such as chromium is deposited, and the metal substance is patterned into a circular shape. Next, the substrate is dipped in an etching solution, and the etching solution is infiltrated between the circular patterns made of a metal substance to dissolve SiO2. The formed microlens 211 does not need to be arcuate and may be trapezoidal. Finally, the substrate is immersed in an etching solution of a metal substance to remove the metal substance. As described above, the protrusions as the microlenses made of the transparent material are formed.

In the off state, the refractive index of the liquid crystal 23 is about 1.6. For example, when the microlens 211 is made of SiO2, the refractive index is about 1.45 to 1.50, so that the incident light is refracted at the interface between the microlens 211 and the liquid crystal 23 according to Snell's law. Further, since the microlens 211 has a pattern which is regularly manipulated, the light is bent due to the influence of the diffraction effect. The ratio and efficiency of refraction and diffraction change depending on the wavelength λ of the light to be modulated. When the length of 10 times the wavelength λ is larger than the pitch of the microlenses, the diffraction effect becomes larger. The bent light is scattered while passing through the liquid crystal 23. Now
If a condenser lens is arranged so that only light within a predetermined angle θ is condensed on the light output side, it means that the light refracted by the microlens has its principal ray angle changed, Compared to the case without a micro lens,
It becomes difficult for light to be condensed by the condenser lens. Therefore, the transmitted light of the light when the liquid crystal is in the off state becomes small.

In the ON state, the refractive index of the liquid crystal is about 1.5 of the ordinary light refractive index. Therefore, it is considerably close to the refractive index of SiO2. Therefore, most of the light at the interface between the microlens 211 and the liquid crystal 23 goes straight without refracting or diffracting. From the above, the contrast becomes large. The above description is for the case where SiO2 is used as the material for forming the microlens. If the polymer used for the liquid crystal layer is used as the material of the lens, the ordinary refractive index no of the liquid crystal and the refractive index nd of the microlens can be matched. Therefore, it goes without saying that the linearity of the incident light when the liquid crystal is in the on state is further improved.

A liquid crystal panel having another structure of the third embodiment is shown in FIGS. 23 (a) and 23 (b). (FIG. 23 (b)) is a cross-sectional view taken along the line CC ′ of FIG. 23 (a). This is an example in which the center of the microlens 211c is formed in a concave shape instead of a convex shape. Even if formed in this way, it is apparent that there is no change in the effect of reducing the transmitted light in the off state of the liquid crystal.

Although the microlens 211 is shown as one independent lens in FIGS. 21 and 23, it may have a stripe shape. Other configurations such as those described in the first embodiment are also conceivable, but the description is omitted here.

The liquid crystal projection device using the liquid crystal panel of the third embodiment has the same structure as that shown in (FIG. 12) in the first embodiment, and the description thereof will be omitted.

The liquid crystal panel of the fourth embodiment of the present invention will be described below. The structure of the liquid crystal panel is almost the same as the structure shown in the first embodiment. However, the dielectric constant of the layer 15 having an uneven cross section needs to be different from that of the polymer-dispersed liquid crystal layer 23, and a low dielectric constant is preferable.
The refractive index of the layer 15 having an uneven cross section does not have to match the refractive index of the polymer-dispersed liquid crystal layer 23, and it is effective even if the convex portions or the concave portions are not formed at regular intervals. .. The operation of the liquid crystal panel of the present invention will be described below with reference to (FIG. 24).

FIG. 24 is an explanatory diagram for explaining the operation of the liquid crystal panel of the present invention. 24 in (FIG. 24)
1a and 241b are liquid crystal molecules, and 242a and 242b are lines of electric force. FIG. 24 shows the case where a voltage at which the liquid crystal starts to be aligned (hereinafter referred to as alignment start voltage) is applied to the counter electrode. The alignment start voltage depends on the film thickness of the liquid crystal 15, the film thickness and pitch of the low dielectric constant film 17, etc.
It is 3V. When a voltage is applied, lines of electric force are generated in the liquid crystal layer. Note that, for ease of explanation, the lines of electric force are assumed to reach the pixel electrode 14 from the counter electrode 22. Since a voltage drop occurs in the low dielectric constant film 15, the number of lines of electric force passing through the film 15 is small. The lines of electric force are well transmitted through the liquid crystal layer due to the relative permittivity. Therefore, the line of electric force from the counter electrode 22 extends from between the low dielectric constant films 15 toward the pixel electrode. The liquid crystal molecules are aligned in the vector direction of the lines of electric force. Liquid crystal molecules 2 in the central portion between the low dielectric constant films 15
41b is vertically oriented and its refractive index is n ₀ . Since the lines of electric force 242a are bent, the liquid crystal molecules 241a are also oriented with an inclination with respect to the normal axis of the electrode substrate. Therefore,
Its refractive index is an intermediate refractive index between n _x and n _a . From the above, when the alignment start voltage is applied, the refractive index of the liquid crystal as a whole becomes high, and the refractive index difference Δn with the polymer becomes large. From this, the scattering performance is improved.

The liquid crystal panel is driven by applying a voltage in the range of the alignment start voltage and the transmission voltage to the pixel electrode. By applying the orientation start voltage, the scattering characteristics are improved as compared to when no voltage is applied, and therefore the contrast is increased.

The liquid crystal projection device using the liquid crystal panel of the fourth embodiment has the same structure as that shown in (FIG. 12) in the first embodiment, and the description thereof will be omitted.

[0095]

As described above, since the liquid crystal panel of the present invention uses the polymer-dispersed liquid crystal, it is possible to obtain a high-brightness screen which is more than twice as bright as the liquid crystal panel using the TN liquid crystal. Further, the following three cases are effective due to the layer having the uneven cross-sectional shape formed in the liquid crystal panel.

First, when the concave portions and the convex portions of the layer having the uneven cross-sectional shape are formed with regular periodicity, the layer having the uneven cross-sectional shape acts as a diffraction grating. When the liquid crystal is in the off state, a difference in refractive index occurs between the liquid crystal layer and the diffraction grating, and the diffraction grating functions. Therefore, the light incident on the liquid crystal panel is diffracted. This means that the amount of light going straight is reduced, and the apparent scattering power is increased. Due to the above diffraction effect, the contrast of the liquid crystal panel is significantly improved. At this time, when the scattering power of the polymer dispersed liquid crystal layer is small, the liquid crystal panel can control only the diffraction effect by the voltage. In this case, since the scattering effect is unnecessary, the thickness of the polymer dispersed liquid crystal layer can be made thinner than that of the conventional polymer dispersed liquid crystal panel. Therefore, the drive voltage can be lowered and the response speed can be increased.
Conversely, when the liquid crystal is in the on state, there is almost no difference in the refractive index from the liquid crystal layer, and the diffraction grating is not formed. Therefore, the light incident on the liquid crystal panel goes straight without being diffracted.

Next, even when the concave portions and the convex portions of the layer having the uneven cross-sectional shape are not formed with regular periodicity, the light beam is bent due to the refractive index difference between the uneven cross-sectional shape layer and the liquid crystal layer. This improves the apparent scattering power.

Thirdly, when the dielectric constants of the layer having an uneven cross-sectional shape and the liquid crystal layer are different, the lines of electric force of the electric field applied to the liquid crystal are bent, and the apparent refractive index of the liquid crystal aligned along this line. Will be higher. Therefore, the difference in refractive index between the liquid crystal and the polymer is increased, and the scattering performance is improved.

Since polymer-dispersed liquid crystal is used as the liquid crystal, the alignment treatment is unnecessary, so that there is no problem even if the substrate has irregularities. Further, since the layer having the uneven cross-sectional shape is formed of the light transmissive substance, the aperture ratio of the pixel is not lowered. Conventionally, since the adhesion between the liquid crystal layer and the counter electrode and the pixel electrode was poor, the problem of peeling occurred, but in the present invention, unevenness is formed on at least one of the counter electrode and the pixel electrode of the liquid crystal panel. It is possible to eliminate this problem.

When the above-mentioned liquid crystal panel of the present invention is used in the liquid crystal projection device of the present invention, its effect is remarkable. The contrast of the image can be significantly improved by improving the diffraction effect and / or the scattering effect of light, and the problem of peeling caused by the heat shock when the power is turned on / off does not occur.
Further, according to the present invention, the contrast of the entire image can be significantly improved by changing the height and pitch of the diffraction grating of the liquid crystal panel for R mainly with other panels.

[Brief description of drawings]

FIG. 1 is a plan view of one pixel of a liquid crystal panel of the present invention.

FIG. 2 is a sectional view of a liquid crystal panel according to a first embodiment of the present invention.

FIG. 3 is a cross-sectional view of a liquid crystal panel having another configuration example of the present invention.

FIG. 4 is a sectional view of an embodiment of a reflective liquid crystal panel of the present invention.

FIG. 5 is a cross-sectional view of a reflective liquid crystal panel having another configuration example of the present invention.

FIG. 6 is a cross-sectional view of a liquid crystal panel having another configuration example of the present invention.

FIG. 7 is a cross-sectional view of a liquid crystal panel having another configuration example of the present invention.

FIG. 8 is a cross-sectional view of a liquid crystal panel having another configuration example of the present invention.

FIG. 9 is a model diagram of lines of electric force in the liquid crystal panel of the present invention.

FIG. 10 is a plan view of one pixel of a liquid crystal panel of another configuration example of the present invention.

FIG. 11 is a cross-sectional view of a liquid crystal panel having another configuration example of the present invention.

FIG. 12 is a configuration diagram of an embodiment of a liquid crystal projection device of the present invention.

FIG. 13 is another configuration diagram of the liquid crystal projection device of the present invention.

FIG. 14 is another configuration diagram of the liquid crystal projection device of the present invention.

FIG. 15 is a sectional view of a liquid crystal panel of another embodiment of the present invention.

FIG. 16 is a schematic diagram showing a principle configuration of a liquid crystal projection device according to an embodiment of the present invention.

FIG. 17 is a configuration diagram of a liquid crystal projection device according to another embodiment of the present invention.

FIG. 18 is a schematic diagram showing a principle configuration of a liquid crystal projection device having another configuration of the present invention.

FIG. 19 is a plan view of a fly-eye lens.

FIG. 20 is a configuration diagram of a liquid crystal projection device having another configuration of the present invention.

FIG. 21 is a plan view of one pixel of a liquid crystal panel of another embodiment of the present invention.

FIG. 22 is a sectional view of a liquid crystal panel according to an embodiment of the present invention.

FIG. 23 is a plan view of one pixel of a liquid crystal panel having another structure of the present invention.

FIG. 24 is a model diagram of lines of electric force in a liquid crystal panel of another embodiment of the present invention.

FIG. 25 is a plan view of a conventional liquid crystal panel.

FIG. 26 is a plan view and a sectional view of a conventional liquid crystal panel.

FIG. 27 is a sectional view of a conventional liquid crystal panel.

FIG. 28 is a configuration diagram of a conventional liquid crystal projection device.

FIG. 29 is an explanatory diagram of the operation of the TN liquid crystal panel.

FIG. 30 is an explanatory diagram of the operation of the polymer dispersed liquid crystal panel.

[Explanation of symbols]

11 Gate Signal Line 12 Source Signal Line 13 TFT 14 Pixel Electrode 15 Concavo-Convex Cross Section Layer 16 Array Substrate 21 Counter Substrate 22 Counter Electrode 23 Polymer Dispersed Liquid Crystal Layer 32 Black Matrix 42 Reflective Electrode 91, 241 Liquid Crystal Molecule 121 Condensing Optical System 122 Infrared cut mirror 123a, 123b, 123c Dichroic mirror 124a, 124b, 124c Polymer dispersed liquid crystal panel 125a, 125b, 125c, 127a, 127b,
127c lens 126a, 126b, 126c aperture 161 input mask 162 output mask 163 Schlieren lens 164 light source 165 screen 166 concave mirror 211 microlens 300 drive circuit

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location H04N 9/12 B 8943-5C 9/31 C 8943-5C

Claims (33)

[Claims] 1. A first substrate and a second substrate facing each other, at least one of which has a light-transmitting property, an electrode layer formed on surfaces of the first and second substrates facing each other, and the first substrate and the second substrate. A polymer-dispersed liquid crystal layer sandwiched between a first substrate and a second substrate; and an uneven cross-sectional shape formed on a surface of at least one of the first and second substrates on which electrodes are formed. A liquid crystal panel comprising a layer. 2. The liquid crystal panel according to claim 1, wherein the layer having an uneven cross-sectional shape is formed of a medium having a light transmitting property. 3. The liquid crystal panel according to claim 1, wherein the layer having an uneven cross-sectional shape is formed of an optically isotropic medium. Wherein irregularities refractive index layer having a sectional shape of, either substantially match either the ordinary refractive index n _o or the extraordinary refractive index n _e of the liquid crystal material used, or the liquid crystal material is in random The liquid crystal panel according to claim 1, wherein the refractive index n _{x in} the aligned state is substantially the same. 5. The liquid crystal panel according to claim 1, wherein a layer having an uneven cross-sectional shape is formed by using a polymer material forming a polymer dispersed liquid crystal layer. 6. The liquid crystal panel according to claim 1, wherein the uneven cross section has a rectangular cross section. 7. The film thickness of the polymer-dispersed liquid crystal is 5 μm or more and 25 μm or more.
The liquid crystal panel according to claim 1, wherein the liquid crystal panel has a thickness of m or less. 8. The liquid crystal panel according to claim 1, wherein the layer having an uneven cross-sectional shape has a stripe shape. 9. The liquid crystal panel according to claim 1, wherein the layer having an uneven cross-sectional shape is a protrusion having a columnar convex portion. 10. The liquid crystal panel according to claim 1, wherein the electrode is exposed in the concave portion of the layer having the uneven cross-sectional shape, and the layer is formed only in the convex portion. 11. A liquid crystal panel according to claim 1, a light generating means, a first optical element part for guiding the light generated by the light generating means to the liquid crystal panel, and a light modulated by the liquid crystal panel. A liquid crystal projection device comprising: a second optical element component for projecting. 12. The light generated by the light generating means is separated by a color filter into light having three predetermined wavelengths of blue light, green light and red light, and the liquid crystal panel has light having wavelengths of the three predetermined ranges. 12. The liquid crystal projection device according to claim 11, wherein the liquid crystal projection device is arranged for at least one of the above. 13. The liquid crystal projection device according to claim 12, wherein the color filter is a dichroic mirror. 14. An optical image of a liquid crystal panel that modulates blue light, an optical image of a liquid crystal panel that modulates green light, and an optical image of a liquid crystal panel that modulates red light are at the same position on the screen by optical element parts. 13. The liquid crystal projection device according to claim 12, wherein the liquid crystal projection device is projected on the screen. 15. A first substrate and a second substrate facing each other, at least one of which has a light-transmitting property, an electrode layer formed on surfaces of the first and second substrates facing each other, and the first substrate and the second substrate. 1
And a polymer-dispersed liquid crystal layer sandwiched between a second substrate and a layer having an uneven cross-sectional shape formed on the surface of at least one of the first and second substrates on which the electrodes are formed. And a concave portion and a convex portion of the layer having the uneven cross-sectional shape are diffraction gratings. 16. The liquid crystal panel according to claim 15, wherein the electrode formed on the second substrate is a reflective electrode. 17. The liquid crystal panel according to claim 16, wherein the layer having an uneven cross-sectional shape is formed on the reflective electrode formed on the second substrate. 18. The liquid crystal panel according to claim 15, wherein a material forming a layer having a concave-convex cross-sectional shape has a dielectric constant equal to that of liquid crystal. 19. The repeating pitch of concave and convex portions is 1.
The liquid crystal panel according to claim 15, wherein the liquid crystal panel has a thickness of 5 μm or less. 20. The liquid crystal panel according to claim 15, wherein the height of the convex portion is 1 μm or more and 10 μm or less. 21. The liquid crystal panel according to claim 15, wherein the maximum inclination angle of the convex portion is 0 degree or more and 45 degrees or less with respect to the normal line of the electrode substrate. 22. The thickness of the polymer dispersed liquid crystal layer is less than 5 μm,
The average particle diameter of the liquid crystal droplets held by the polymer of the polymer dispersed liquid crystal layer or the average void spacing of the polymer is less than 1 μm,
The ratio of the liquid crystal material of the polymer dispersed liquid crystal layer is 90% by weight or more,
The liquid crystal panel according to claim 15, wherein at least one of the conditions is satisfied. 23. The liquid crystal panel according to claim 22, wherein the height of the convex portion of the layer having the uneven cross-sectional shape and the thickness of the polymer dispersed liquid crystal layer are substantially the same. 24. A liquid crystal panel according to claim 15, a light generating means, a first optical element part for guiding the light generated by the light generating means to the liquid crystal panel, and a light modulated by the liquid crystal panel. A liquid crystal projection device comprising: a second optical element component for projecting. 25. A Schlieren optical system is provided in the optical path,
25. The liquid crystal projection device according to claim 24, wherein an image formed by the liquid crystal panel is enlarged and projected through the schlieren optical system. 26. In a liquid crystal panel arranged for light of each wavelength, at least one of height and pitch of layers having an uneven sectional shape formed in one or more liquid crystal panels of the liquid crystal panels. 25. The liquid crystal projection device according to claim 24, which is different from other liquid crystal panels. 27. A first substrate and a second substrate, at least one of which has a light-transmitting property, facing each other; an electrode layer formed on the surfaces of the first and second substrates facing each other; 1
And a polymer-dispersed liquid crystal layer sandwiched between the second substrate and at least one of a convex shape and a concave shape formed on the surface on which the electrode is formed on at least one of the first and second substrates. A liquid crystal panel comprising a layer having a cross-sectional shape of one shape. 28. The liquid crystal panel according to claim 27, wherein the concave sectional shape is a concave lens sectional shape. 29. The liquid crystal panel according to claim 27, wherein the convex sectional shape is a convex lens sectional shape. 30. A first substrate and a second substrate, at least one of which is transparent to light, facing each other; an electrode layer formed on the surfaces of the first and second substrates facing each other; 1
And a polymer-dispersed liquid crystal layer sandwiched between a second substrate and a layer having an uneven cross-sectional shape formed on the surface of at least one of the first and second substrates on which the electrodes are formed. The liquid crystal panel, wherein the layer having the uneven cross-sectional shape has a dielectric constant different from that of the polymer-dispersed liquid crystal layer. 31. A layer having a concavo-convex cross-sectional shape is provided on a second substrate above the signal line of a first substrate on which a pixel electrode and a signal line and a switching element for controlling a signal to the pixel electrode are formed. 31. The liquid crystal panel according to claim 30, which is formed on at least an electrode substrate. 32. The liquid crystal panel according to claim 30, wherein the maximum inclination angle of the convex portion is 45 degrees or more with respect to the normal line of the electrode substrate. 33. A liquid crystal panel according to claim 27 or 30, a light generating means, a first optical element part for guiding the light generated by the light generating means to the liquid crystal panel, and the light modulated by the liquid crystal panel. A liquid crystal projection device comprising: a second optical element component that projects light.