JPH0829802A - Animation image projector - Google Patents

Abstract

PURPOSE:To make it possible to project animation images to be projected as bright images with high accuracy by making efficiency of utilizing luminous fluxes figher by composing the optical modulation material of an optical writing type spatial optical modulator of a monostable type ferroelectric liquid crystal. CONSTITUTION:This animation image projector has an optical writing type spatial optical modulator 1, the so-called light valve, an electric address type writing light source section 2 which executes optical writing to this optical writing type spatial optical modulator 1, a projecting light source section 3 and a projecting optical system 4. The optical modulation material of the optical writing type spatial optical modulator 1 is formed out of a monostable type ferroelectric liquid crystal and in addition, the modulator 1 is not formed in a X, Y electrode wiring structure, etc., but is formed to be of optical writing type spatial optical modulator constitution. The optical images corresponding to the projected animation from the electric address type writing light source section 2 is written into the optical writing type spatial optical modulator 1. The light from the projecting light source section 3 is optically modulated by such optical writing type spatial optical modulator 1 to obtain the projected animation images. These images are projected to a screen via the projecting optical system 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moving image projection apparatus.

[0002]

2. Description of the Related Art Various types of moving image projectors have been proposed. For example, as a moving image projection device for obtaining a projection screen having a diagonal size of 40 to 200 inches, a device for directly projecting a self-luminous image of a cathode ray tube on a screen, a light from a lamp is modulated by a spatial light modulator such as a liquid crystal display device. There are things to project.

However, it is difficult to obtain a bright and excellent projected image with a self-luminous image of the cathode ray tube in a moving image projection apparatus which directly projects the self-luminous image of the cathode ray tube onto the screen. Therefore, a moving image projection apparatus, in which light from a lamp as a projection light source is modulated by a spatial light modulator such as a liquid crystal display element and projected, is attracting attention.

By the way, as the liquid crystal display element, a matrix display of X and Y electrode wiring types orthogonal to each other or an active matrix display by a matrix arrangement of switching elements such as thin film transistors is generally used.

On the other hand, when a monostable ferroelectric liquid crystal is used as the liquid crystal material, this liquid crystal has a sufficiently thin liquid crystal layer and a sufficient optical rotation characteristic as compared with a normal TN (twist nematic) liquid crystal. Since it is possible to obtain high resolution, it is expected that a high-definition moving image projection apparatus can be configured, and since the degree of light modulation continuously changes according to the applied voltage, multi-gradation display is possible. Has the advantage that it can be performed easily.

However, even if the above-mentioned moving image projection apparatus is constructed using a liquid crystal device using such a monostable ferroelectric liquid crystal, the characteristics of the ferroelectric liquid crystal are not fully utilized. This is because in the case of the above-mentioned X, Y electrode wiring type matrix display or the active type matrix display by the matrix arrangement of switching elements such as thin film transistors, there is a problem of sufficient electrode due to the electrode wiring, the arrangement of the switching elements, and the occupied area. It is impossible to achieve high density, and therefore the high resolution characteristics of the ferroelectric liquid crystal cannot be fully utilized, which impedes high-definition moving image projection. Further, due to the above-described problems of the electrode wiring, the arrangement of the switching elements, and the occupied area, there is a problem that a sufficiently high effective display area, that is, high luminous flux utilization efficiency cannot be achieved.

[0007]

SUMMARY OF THE INVENTION The main object of the present invention is, for example, to project a projected moving image having a diagonal size of 50 inches or more,
(EN) Provided is a moving image projection device capable of projecting a bright image with high definition and high luminous flux utilization efficiency.

[0008]

The first aspect of the present invention, as shown in FIG. 1 for the schematic configuration of an example thereof, is an optical writing type spatial light modulator 1, a so-called light valve, and this optical writing type spatial light modulator. 1. An optical address type writing light source unit 2 for performing optical writing on the optical writing device 1, a projection light source unit 3, and a projection optical system 4, and the optical modulation material of the optical writing type spatial light modulator 1 is a monostable type. The structure is made of a ferroelectric liquid crystal.

The second aspect of the present invention is similar to the above-mentioned aspect of the invention, and includes an optical writing type spatial light modulator 1, and an electric address type writing light source section 2 for performing optical writing on the optical writing type spatial light modulator 1. The projection address light source unit 3 and the projection optical system 4 are provided, and the electric address type writing light source unit 2 is constituted by an electronic address type thin film fluorescent surface type cathode ray tube which is electrically connected.

The thin-film fluorescent surface type cathode ray tube is usually formed by applying a so-called phosphor slurry, which is a mixture of phosphor powder in a conventional television picture tube and the like, to a binder on the inner surface of the face plate of the cathode ray tube. It does not have a direct-view type cathode ray tube structure, but refers to a cathode ray tube having a single crystal thin film or a dense polycrystalline thin film phosphor screen.

[0011]

In the configuration of the present invention, an optical image corresponding to the projected moving image from the electric address type writing light source unit 2 is written in the optical writing type spatial light modulator 1, and the projection light source unit 3 is used by the optical writing type spatial light modulator 1. Is modulated to obtain a projected moving image, which is projected onto a target screen via the projection optical system 4.

As described above, according to the present invention, the projection light source unit 3
And adopts a mode in which this is modulated by the optical modulator 1,
Since it is possible to perform a sufficiently bright projection display, and further, since the optical modulator 1 is not provided with the X, Y electrode wiring, the thin film transistor of the switching element, or the like,
A high luminous flux utilization efficiency can be achieved, and a sufficiently bright projected moving image can be secured.

In the first aspect of the present invention, the modulation material of the modulator 1 is a monostable ferroelectric liquid crystal, and the modulator 1 is not based on the X, Y electrode wiring structure or the like. Since the optical writing type spatial light modulator is used, the high-resolution characteristic described at the beginning of the monostable ferroelectric liquid crystal can be utilized, and the high-definition optical modulation can be achieved, and accordingly, the high quality of the projected moving image can be achieved. The definition can be improved.

Further, in the second aspect of the present invention, the electric address type writing light source section 2 for performing the optical writing to the optical writing type spatial light modulator 1 is constituted by a thin film fluorescent surface type cathode ray tube. In the case of this configuration, since the phosphor screen has a denseness, a high-definition image can be obtained, and writing in the optical writing type spatial light modulator 1 can be performed with high definition. .

If the above-described first and second aspects of the present invention are combined, a high-definition optical image is obtained by the high-definition optical image obtained by the electric address type writing light source unit 2 using the thin film fluorescent surface type cathode ray tube. The projected image is more surely made to have a higher definition by the light modulation by the light writing type spatial light modulator 1 using the monostable ferroelectric liquid crystal of the light modulating material capable of being modulated.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An example of the moving image projection apparatus according to the present invention will be described with reference to FIG. The device of the present invention comprises an optical writing type spatial light modulator, a so-called light valve 1, an electric address type writing light source unit 2 for performing optical writing on the optical writing type spatial light modulator 1, a projection light source unit 3, and a projection optical system. 4 and 4.

The optical address type write light source section 2 is optically coupled to the optical write type spatial light modulator 1 by an image fiber plate 5, for example.

The optical writing type spatial light modulator 1 is formed between an image fiber plate 5 and a transparent substrate, for example, a glass substrate 11 facing the image fiber plate 5. The optical writing type spatial light modulator 1 includes, for example, an image fiber plate 5
One transparent electrode 12 deposited on the photoconductive layer 13 and a photoconductive layer 13 made of a semiconductor such as hydrogenated amorphous silicon (a-Si) or cadmium selenide (CdSe) are deposited on the dielectric multilayer film. And a light reflection layer 14 made of a transparent material, and the other transparent electrode 15 is formed on the inner surface of one transparent substrate 11 between the transparent electrodes 12 and 15, that is, the image fiber plate 5 and the transparent substrate 11. A liquid-tight space is formed between them, and the liquid-tight space is filled with a liquid crystal, particularly a monostable ferroelectric liquid crystal 16.

The monostable ferroelectric liquid crystal 16 of the light modulating material of the optical writing type spatial light modulator 1 is disclosed in Japanese Patent Laid-Open No. 4-212.
A chiral liquid crystal in the liquid crystal display element of Japanese Patent No. 126,
A composition obtained by mixing a fluorine-substituted derivative of a tricyclic ester, a non-chiral liquid crystal such as a phenylpyrimidine type or a phenylbenzoate type can be used.

The electric address type writing light source unit 2 is constituted by a thin film fluorescent surface type cathode ray tube by electronic address type writing, which mainly involves electricity. Then, the fluorescent screen 21 of the cathode ray tube and the photo-writing type spatial light modulator 1, for example, a light emission image obtained on the fluorescent screen 21 of the cathode ray tube by the image fiber plate 5 also serving as the face plate of the cathode ray tube The light is transmitted to the spatial light modulator 1.

The thin film fluorescent surface type cathode ray tube which serves as the electric address type writing light source section 2 is, for example, a cathode K, a grid 22 for leading out an electron beam b from this, and an anode 23 in a tube body maintained at a high degree of vacuum. And a thin film phosphor screen 24 is formed on the face plate of the tube, that is, the inner surface of the image fiber plate 5 in the illustrated example, facing the electron gun. The electron beam b is focused by the focusing electromagnetic coil 25 and is deflected by the deflecting electromagnetic coil 26.
Thus, the fluorescent screen 21 is horizontally and vertically scanned.

The thin-film fluorescent screen 21 is formed as a single-crystal thin film or a dense polycrystalline thin-film fluorescent screen, and the fluorescent screen 21 of the cathode ray tube does not cause penetration of the electron beam b and has a high light quantity. For example, 0.1 μm to 10 μm, which is a thickness of the obtained phosphor, which shows high luminous efficiency and at the same time does not interfere with the emission to the face plate (image fiber plate 5) by being absorbed or scattered by the phosphor screen itself. The thickness is preferably 0.5 μm to 3 μm, more preferably 1 μm to 2 μm.

The thin film phosphor screen 21 is composed of, for example, a polycrystalline phosphor film densely formed by vapor deposition, or a single crystal phosphor film to which a semiconductor technique is applied. This phosphor may be ZnSiO ₄ , AlGaAs, InGa.
It can be formed by, for example, epitaxy or vapor deposition of a compound semiconductor of P, ZnSe, ZnS, CdS or the like. Phosphor screen 2
1 is formed of a single crystal phosphor film, for example, by forming an epitaxial layer of the above phosphor on a single crystal substrate,
Peeling this epitaxial phosphor layer from the substrate,
The substrate is formed by removing it by chemical or mechanical / chemical polishing, and this is formed into a face plate of a cathode ray tube body, for example, the image fiber plate 5 described above.
It can be configured by bonding to.

The material of the light emitted from the fluorescent surface 21 is selected so that the photon energy larger than the energy gap of the photoconductive layer 13 of the above-described photo-writing type spatial light modulator 1 is emitted.

As described above, the phosphor screen 21 is a phosphor surface having a high degree of compactness. When it is composed of a polycrystalline film, the voids between crystal grains are 0.1 μm.
It becomes the following. By the way, the space between the phosphor particles on the phosphor surface formed by applying and baking a phosphor slurry in which a binder or the like is mixed together with a general phosphor powder is usually close to 1 μm or more. It is formed as a surface.

The projection light source section 3 includes, for example, a light source lamp 31.
And the spherical reflecting mirror 32 arranged on the back of the
2 and a collimator lens 33 that faces the lamp 2 with the lamp 31 interposed therebetween.

The parallel light from the projection light source unit 3 is introduced into the optical writing type spatial light modulator 1 via the deflecting beam splitter 6.

On the other hand, the light from the optical writing type spatial light modulator 1 is projected onto a screen (not shown) via the deflecting beam splitter 6 and the projection optical system 4, that is, the projection lens.

The operation of the moving image projection apparatus having the above-described structure will be described. The transparent electrode 1 of the optical writing type spatial light modulator 1 is described.
A predetermined voltage is applied between 2 and 15. In this state, by scanning the fluorescent screen 21 with the electric address type writing light source unit 2, that is, the electron beam b whose density is modulated by the cathode ray tube according to the projection image in the above-mentioned configuration,
The phosphor screen 21 emits light to emit a desired projected moving image optical image. This light emission optical image is faithfully introduced into the photoconductive layer 13 of the optical writing type spatial light modulator 1 by the image fiber plate 5, and the conductivity of this photoconductive layer 13 is changed into a pattern according to the incident optical image. That is, the conductivity of each part varies depending on the magnitude of the light input. Therefore, the voltage between the transparent electrodes 12 and 15 is applied to the liquid crystal 16 in this portion according to its magnitude in the portion where the light is input, and the optical rotation characteristic of the liquid crystal 16 is modulated in this portion.

At this time, since polarized light having a predetermined polarization plane is introduced from the projection light source unit 3 into the optical writing type spatial light modulator 1 by the polarization beam splitter 6, this polarized light is converted into this optical writing type spatial light modulation. Due to the modulated optical activity of the liquid crystal 16 in the container 1, its polarization angle is modulated according to the above-mentioned optical image.

In this way, the optical image whose polarization angle is modulated is reflected by the light reflection layer 14, and only the light whose polarization angle is modulated goes to the projection optical system 4 through the polarization beam splitter 6. As a result, a moving image is projected. Therefore, this projection image eventually projects an optical image corresponding to the light emission moving image of the electric address type writing light source unit 2, that is, the cathode ray tube.

In this case, the optical writing type spatial light modulator 1 uses the light modulation material as a monostable ferroelectric liquid crystal 16.
Since this liquid crystal can obtain sufficient optical rotation characteristics with a sufficiently thin liquid crystal layer thickness as described above, it has a high resolution (for example, about 100 [line pair / m
m]), it is possible to obtain a moving image projection image by being able to perform high-definition light modulation, and furthermore, since the light modulation degree continuously changes according to the applied voltage, a multi-gradation projection image can be obtained. It can be carried out.

Further, this optical writing type spatial light modulator 1
A writing light source for writing the projection optical image,
That is, since the electric address type writing light source unit 2 is composed of a thin film fluorescent surface type cathode ray tube whose fluorescent surface 21 is rich in denseness, that is, a high resolution and therefore a high definition optical image can be obtained. A high-definition optical image is written in the optical modulator 1. Therefore, in this optical modulator 1, it is possible to obtain a high-definition light modulation, and thus a high-definition projected image. In this case, in particular, as described above, the optical writing type spatial light modulator 1 can be obtained. When a monostable ferroelectric liquid crystal is used for the above, the effect of high-definition light modulation can be sufficiently exhibited.

In the above-mentioned configuration, the optical address type writing light source section 2 is optically coupled to the optical writing type spatial light modulator 1 by the image fiber plate 5. In this case, Since the optical coupling can avoid the interposition of the lens and the space, the configuration is simple and compact.

To explain this, when the above-mentioned cathode ray tube type configuration is adopted in the electric address type writing light source unit 2 described above, the spread width of the electron beam b due to the design of the electron gun and electron lens system is 1 μm. ~ 5 μm
When irradiating the fluorescent surface 21 with the following spot diameter, the emission spot diameter on the fluorescent surface 21 is about the square root of the sum of squares of the spot diameter of the electron beam and the diffusion length of charges (particularly holes) in the phosphor. That is, the range is 1 μm to 5 μm, and the emission spot diameter can be 10 μm or less. The image fiber plate 5 has a core diameter of 3 μm to 6 μm.
Since the one having a thickness of μm has been put to practical use, the spread of light in the image fiber plate 5 can be effectively suppressed by using this.

Then, until the light generated in the phosphor is incident on the image fiber plate 5 and is emitted from the image fiber plate 5 and is absorbed by the photoconductive film 13 of the optical writing type spatial light modulator 1. Although the resolution of the written image lowers due to the spread of the light, the spread can be suppressed to 10 μm or less by using the phosphor as a thin film phosphor having a high density as described above.

Therefore, in the case of the above configuration, the optical writing type spatial light modulator 1 has a high resolution (50 to 100).
[Line pair / mm]) image writing is possible. By the way, when the cathode ray tube type electric address type writing light source unit 2 having a so-called powder phosphor screen of a normal phosphor slurry is used, the phosphor powder has a large particle size of several tens of μm and is dense. Therefore, the resolution is 10 because of the reason that the light generated on the fluorescent screen is diffusely reflected before it goes out from the fluorescent screen.
It is difficult to exceed [line pair / mm]. Therefore, in order to write a high-definition image (1000 TV lines or more), it is necessary to set the screen size of the cathode ray tube to, for example, a diagonal of 4 inches or more. When using the small optical writing type spatial light modulator 1, It is necessary to combine images from the cathode ray tube of the address-type writing light source unit 2 through the reduction projection optical system, which hinders downsizing of the entire apparatus.
On the other hand, when the above-described thin-film phosphor screen type cathode ray tube configuration is adopted, such inconvenience is avoided and a compact and simple configuration can be adopted.

In the above example, a single color projection image is obtained, but a color projection image can be obtained by the configuration of the present invention. That is, in this case, for example, white light from the projection light source unit 3 is separated into three primary colors of red, green, and blue by a color-selective half mirror, and the polarization beam splitter 6 and the optical writing type spatial light described above for each color light are separated. It is also possible to project the color projected image by providing the modulator 1 and the electric address type writing light source unit 2 for the modulator 1 and obtaining the projected images of the respective colors, superimposing them and synthesizing them on the screen.

In the second aspect of the present invention, the electric address type writing light source unit 2 has an electron address type cathode ray tube structure in which the fluorescent surface 21 is excited by an electron beam. As the light emitting diode configuration, it is possible to adopt an electric address type configuration with various configurations, such as a configuration in which each pixel is driven and emitted by the X and Y wirings in directions orthogonal to each other.

Needless to say, the configurations of the projection light source unit 3 and the projection optical system 4 are not limited to the above examples.

[0041]

As described above, according to the present invention, since the projection light source unit 3 is used and is modulated by the light modulator 1, a sufficiently bright projection display can be performed. The modulator 1 has an X,
Since the Y electrode wiring and the thin film transistor of the switching element and the like are not arranged, it is possible to achieve high luminous flux utilization efficiency and secure a sufficiently bright projected image.

In the first aspect of the present invention, the modulation material of the modulator 1 is a monostable ferroelectric liquid crystal, and the modulator 1 has an optical writing type spatial light modulator structure. Therefore, the high-resolution characteristic described at the beginning of the monostable ferroelectric liquid crystal can be utilized, and a high-definition projection image can be obtained according to the high-definition light modulation.

Further, in the second aspect of the present invention, the electric address type writing light source section 2 for performing the optical writing to the optical writing type spatial light modulator 1 is constituted by a thin film fluorescent surface type cathode ray tube. In this case, since the fluorescent screen has a high density, a high-definition optical image can be obtained, and therefore, the writing to the optical writing type spatial light modulator 1 can be performed with a high definition. In addition, as described above, the small and simple structure can be achieved.

In particular, in the case of adopting the structure having both the first and second aspects of the present invention, as described above, the electric address type writing light source unit 2 is used to move the optical writing type spatial light modulator 1 with high precision. Can write the
Further, this optical writing type spatial light modulator 1 carries out high-definition light modulation, so that a projection optical image with higher definition can be obtained.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an example of a moving image projection apparatus according to the present invention.

[Explanation of symbols]

 1 Optical Writing Type Spatial Light Modulator 2 Electric Addressing Writing Light Source Unit 3 Projection Light Source Unit 4 Projection Optical System 5 Image Fiber Plate 6 Polarizing Beam Splitter 16 Monostable Ferroelectric Liquid Crystal 21 Fluorescent Surface

Claims (2)

[Claims] 1. An optical writing type spatial light modulator, an electric address type writing light source section for performing optical writing to the optical writing type spatial light modulator, a projection light source section, and a projection optical system. A moving image projection apparatus, wherein the light modulating material of the writing type spatial light modulator is composed of a monostable ferroelectric liquid crystal. 2. An optical writing type spatial light modulator, an electric address type writing light source section for performing optical writing to the optical writing type spatial light modulator, a projection light source section, and a projection optical system. A moving-image projection device, wherein the address-type writing light source unit comprises a thin-film phosphor screen type cathode ray tube.