JP2943481B2 - Large screen display - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a large-screen display device.

[0002]

2. Description of the Related Art A conventional large-screen display device displays an image displayed on a CRT projection tube of about 7 inches in a single color of red, blue, and green.
A large-screen display device of about 40 inches has been realized by magnifying and projecting the image on a screen through a projection lens and displaying the combined image. However, in such a conventional large-screen display device, in order to perform a further large-screen display, it is necessary to increase the projection magnification, so that the brightness is reduced or a long projection distance is required. There was a problem that the depth became long.

Therefore, while maintaining the depth and brightness,
As a large screen display device capable of further displaying a large screen, the 1989 National Convention of the Institute of Television Engineers of Japan "3-10
As described in "Development of a 12-Screen Multi-Display System for Hi-Vision," there has been a display device having a large screen by arranging a plurality of projection display devices of about 40 inches in length and width.

FIG. 27 is a perspective view showing a multi-display device constructed by combining a number of such conventional projection display devices. In the figure, reference numeral 500 denotes a rear projection type display device. In this example, the projection type display device 500 is arranged in four rows and four columns to form one display screen, and the video signal is quadrupled in each of the vertical and horizontal directions. Each of the projection display devices 500 displays a corresponding part of one screen in an enlarged manner.

FIG. 28 is a configuration diagram showing a cross section of the projection display device 500 in FIG. 28, reference numeral 501 denotes a CRT projection tube; 502, a projection lens;
Reference numeral 3 denotes a projection screen; 504, a screen frame; and 505, a housing for housing and holding the CRT projection tube 501 and the projection lens 502.

The partial image enlarged and displayed on the CRT projection tube 501 shown in FIG. 28 is projected and displayed on a projection screen 503 through a projection lens 502. Here, the projection screen 503 is attached to a housing 505 with its peripheral portion sandwiched by a screen frame 504. In this way, the projection screen 503 sandwiched between the screen frames 504 is arranged on one plane of 4 × 4 to form one large screen screen, and a large screen display device as shown in FIG. 27 is realized. doing.

[0007]

Since the conventional large-screen display device is constructed as described above, when a large number of individual projection-type display devices are combined and arranged, the projection screen 5
Since the screen frame 504 sandwiching the image No. 03 appears on the display screen and non-display portions in the form of vertical and horizontal stripes are generated, there is a problem that image quality is deteriorated.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and it is possible to suppress the occurrence of a non-display portion and the distortion of an image which cause image quality deterioration, and to provide a high-quality large-screen display device. It is intended to provide.

It is another object of the present invention to provide a large-screen display device that can suppress heat generation even when a large number of projection display devices are arranged, and that is thin and capable of high-luminance display.

It is another object of the present invention to provide a large-screen display device capable of displaying a high-contrast display at low cost.

[0011]

According to a first aspect of the present invention, there is provided a large-screen display device, comprising: an optical image forming section for modulating a light emission intensity in a two-dimensional space according to a video signal to form an optical image; A projection type display device including a projection optical system for enlarging and projecting an image, a housing for housing and supporting the optical image forming unit and the projection optical system, and a screen unit for projecting and displaying the optical image enlarged by the projection optical system is provided by a matrix. In a large screen display device arranged in a plurality, the surface of the screen portion on the side of the projection optical system has a concave surface portion having a spherical shape centered on the intersection of the principal ray and the optical axis of the projection optical system, The screen unit and the housing are connected via a surface of the screen unit on the side of the projection optical system.

According to a second aspect of the present invention, there is provided a large-screen display device, comprising: an optical image forming section for modulating a light emission intensity in a two-dimensional space to form an optical image in accordance with a video signal; A plurality of projection display devices each comprising a projection optical system, a housing for housing and supporting the optical image forming unit and the projection optical system, and a screen unit for projecting and displaying the optical image enlarged by the projection optical system. In a large-screen display device arranged, a projection unit for projecting projection light onto the entire screen surface is provided on a surface of the screen unit on the side of the projection optical system, and a Fresnel surface is formed on the side opposite to the projection optical system side. A transparent plate, and the screen unit and the housing are connected via a surface of the screen unit on the side of the projection optical system.

According to a third aspect of the present invention, in the large-screen display device, the optical image forming unit emits light by the light valve on which an image is formed in accordance with a video signal, the electron beam generating means, and the electron beam excitation. A light source tube having a light emitting portion made of a phosphor layer is provided.

According to a fourth aspect of the present invention, there is provided a large-screen display device, wherein the light emitting unit area of the light source tube is smaller than the light valve area, and the side of the light source tube facing the light valve is a convex lens. It is a feature.

According to a fifth aspect of the present invention, there is provided a large-screen display device, wherein a plurality of light-emitting devices each comprising an electron beam generating means and a phosphor layer which emits light of different colors when excited by an electron beam. A light source tube having a portion is provided.

Further, according to a sixth aspect of the present invention, there is provided a large-screen display device, comprising: a front side of the Fresnel surface opposite to the projection optical system;
Lenticular panel with check stripe
And adjust the width of the lenticular panel to the above black strike.
Of the black strike at both ends.
It is noteworthy that the width of the rice
It is a sign.

Further, a large-screen display device according to claim 7 of the present invention is characterized in that the light valve is constituted by a passive liquid crystal panel.

Further, a large-screen display device according to an eighth aspect of the present invention is characterized in that a transparent elastic body is provided around a screen portion.

[0019]

According to the first aspect of the present invention, the screen unit and the housing are configured to be connected via a surface of the screen unit on the side of the projection optical system, and further, the optical image of the optical image forming unit is projected by the projection lens. When projected through the projection screen unit, the principal ray of the projection luminous flux of the optical image is perpendicularly incident on the projection screen unit on the concave surface of the area other than the connection between the projection screen and the housing on the back of the projection screen. for,
The principal ray goes straight as it is, and an optical image without distortion is displayed on the entire surface of the projection screen on the observation surface side. Therefore, even if a large number of projection display devices are combined, no non-display portion and distortion do not occur.

The large-screen display device according to the second aspect of the present invention has a projection means for projecting projection light on the entire surface of the screen, on a surface of the screen unit on the side of the projection optical system.
By providing a transparent plate having a Fresnel surface on the side opposite to the projection optical system side, a non-display portion does not occur even when a large number of projection display devices are combined.

Further, in the large-screen display device according to the third aspect of the invention, since a large number of projection-type display devices using light sources having a phosphor layer which emits light by electron beam excitation are arranged, there is no heat generation and many light sources are used. Even if they are arranged, no cooling device is required.

According to a fourth aspect of the present invention, there is provided a large-screen display device in which the area of the light-emitting portion is reduced, and high-luminance light is emitted by irradiating a fixed amount of an electron beam. Due to the refraction effect of the provided plano-convex lens, most of the light from the light emitting section that emits light with high luminance in a small area enters the light valve and the projection lens.

Further, in the large-screen display device according to the fifth aspect of the present invention, since the light source tubes for emitting light of three colors are housed in one container, the light source tubes are reduced in size and the entire device is made thinner.

Further, the large-screen display device according to the invention of claim 6 is characterized in that a black screen is provided on the Fresnel surface on the side opposite to the projection optical system side.
Install a lenticular panel with a stripe
Adjust the width of the lenticular panel to the
Black strikes at both ends of the pitch
The width of the projection is half of that of other
Even if the display devices are arranged in a matrix,
The junctions of the connection parts are joined with high precision.

Further, in the large-screen display device according to the present invention, since the image quality of the non-display portion at the joint does not deteriorate, the size of one arrayed projection display device can be reduced, and the cost can be reduced. Since the liquid crystal panel can be used, the whole device is inexpensive.

Further, the transparent elastic body according to the invention of claim 8 is applied to the periphery of the projection screen portion of the projection type display device, and the joint portion of the projection screen portion when the projection type display device is arranged is Since the transparent elastic bodies are in close contact with each other, reflection at the end face of the projection screen is reduced.

[0027]

【Example】

Embodiment 1 FIG. FIG. 1 is a configuration diagram showing a cross section of a projection display device constituting a large screen display device according to an embodiment of the present invention, which is a liquid crystal three-plate light valve system.

In the figure, 201 is a halogen lamp light source, and 210 is a mirror. 211 is a blue reflecting dichroic mirror, 212 is a green reflecting dichroic mirror, and reflects only the color of the corresponding wavelength. 213
Is a liquid crystal light valve for blue, 214 is a liquid crystal light valve for green, 215 is a liquid crystal light valve for red, and is composed of an active matrix type liquid crystal cell sandwiched between two polarizing plates. Form an image. 2
Reference numeral 16 denotes a dichroic prism for synthesizing optical images of three colors. Reference numeral 502 denotes a projection lens, and reference numeral 505 denotes a housing. The housing 505 includes a light source 201, a mirror 210, dichroic mirrors 211 and 212, and light valves 213 and 21.
4, 215, the dichroic prism 216, and the projection lens 502 are stored and supported.

Reference numeral 218 denotes a liquid crystal light valve 213;
214, 215 are plano-convex lenses closely attached to the incident light side. Light beams emitted almost in parallel from the halogen lamp 201 are condensed by the projection lens 502, and the image of the light source (2 Next light source). 60
Reference numeral 0 denotes a projection screen, which is formed by laminating a diffusion surface 601 on the viewing surface side and a concave lens-like transparent plate 602 on the projection light incident surface side, which have the same outer shape. The projection screen 600 is attached so as to be connected to the housing 505 via the surface of the concave lens-shaped transparent plate 602 on the projection light incident surface side. Reference numeral 700 denotes a projection display device.

FIG. 2 shows the liquid crystal light valves 213 and 21.
It is a front view which shows the example of a structure of 4, 215. Reference numeral 122 denotes an upper glass substrate, and 123 denotes a lower glass substrate. Liquid crystal is subjected to an appropriate alignment treatment and sealed between the two glass substrates. The lower glass substrate 123 has the display signal line 1
24 and the scanning line 126 are arranged so as to be orthogonal to each other, and a pixel electrode 128 is connected to the intersection through a thin film transistor 129. Display signal line 124
A signal is applied from the outside to the display signal terminal 125 via the scanning signal terminal 127 to the scanning line 126. Further, on the inner surface of the upper glass substrate 122, a counter electrode composed of a transparent electrode is provided. Both glass substrates 122,
Polarizing plates (not shown) are provided on both sides of the 123.

FIGS. 3 and 4 relate to the specific shape of the concave lens-shaped transparent plate 602. FIG. 3 is a perspective view showing a projection screen 600 of the projection display device 700, and FIG. FIG. 3 is a cross-sectional view taken along line I-O-I. In FIG. 4, reference numeral 217 denotes liquid crystal light valves 213 and 21.
4 and 215 are optical images. The concave surface of the concave lens-shaped transparent plate 602 is a spherical surface centered on the projection lens 502. In the figure, A indicates the optical axis.

The operation will be described below. Light emitted from the halogen lamp 201 is separated into blue, green, and red primary color lights by a blue reflecting dichroic mirror 211 and a green reflecting dichroic mirror 212. Further, each color light is light intensity modulated by a blue liquid crystal light valve 213, a green liquid crystal light valve 214, and a red liquid crystal light valve 215, combined by a dichroic prism 216, and then projected by a projection lens 502 toward a projection screen 600. .

Here, in this embodiment, as shown in FIG. 1, an optical system for forming a secondary light source in the projection lens 502 is used. Therefore, as shown in FIG.
Principal rays emitted from each point of the optical image 217 formed on 13, 214, and 215 pass through the center of the projection lens 502, enter the concave surface of the concave lens-shaped transparent plate 602 perpendicularly, and go straight as it is. An image is formed on the diffusion surface 601. The principal ray from the outermost peripheral portion of the optical image 217 is incident on the concave lens-shaped transparent plate 602 near the connection with the housing,
Moving straight from this portion, an image is formed at the outermost peripheral portion of the diffusion surface 601. Therefore, when the projection screen 600 is viewed from the direction opposite to the projection direction, the various liquid crystal light valves 213 and 21
The composite image of the optical images formed on the projection screens 4 and 215 is projected and displayed on the entire surface of the projection screen 600 without distortion.

FIG. 5 is a perspective view showing a multi-type large-screen display device in which a large number of projection display devices 700 are arranged in a matrix. An image is projected and displayed on the entire surface of the projection screen 600 of each projection display device 700,
Since they are arranged tightly and seamlessly, a single large-screen display screen can be constructed without generating a non-display portion.

For example, the various liquid crystal light valves 21 shown in FIG.
If the specifications of 3, 214, and 215 are configured as shown in Table 1, and the projection magnification is 4 times, the display performance of each projection display device is as shown in Table 2.

[0036]

[Table 1]

[0037]

[Table 2]

Accordingly, the projection type display device 700 is
By arranging 27 pixels and 27 pixels horizontally, a large screen display device of a high definition class of 160 inches (about 1.9 m × 3.5 m) and 960 pixels × 1728 pixels can be realized.
Further, in this embodiment, since the projection magnification is set as low as 4 times, the projection distance can be shortened, so that a thin large-screen display device can be realized.

When the screen gain is set to 1,
Since the screen brightness is inversely proportional to the square of the projection magnification,
When the projection magnification is 3 times, the screen luminance is 1/9 of the luminance on the light valve, and when the projection magnification is 4 times, it is 1/16. In the conventional apparatus, the projection magnification is about 10 times, and the luminance is reduced to 1/100. However, when the projection magnification is set to be less than about 4 times, high screen luminance can be secured.

Embodiment 2 FIG. Another embodiment of the projection screen 600 will be described with reference to FIGS. 6, 7, and 8. FIG. FIG. 6 is a perspective view showing a projection screen 600 according to another embodiment of the projection type display device 700, and FIG.
It is an O-II line sectional view. FIG. 8 is a configuration diagram showing an end of the projection screen 600 of FIG. 7 in an enlarged manner. In the figure, reference numeral 606 denotes a Fresnel concave lens-shaped transparent plate having a central portion hollowed out and a Fresnel surface having a concave lens effect formed at the periphery thereof, and the outermost peripheral portion 607 thereof is formed flat.

As shown in FIG. 8, the Fresnel surface around the Fresnel concave lens-shaped transparent plate 606 has surfaces BC, DE,
FG, HI, JK, and planes AB, CD, EF, GH, I
J and KL are formed. Also, as shown in FIG.
The shape of the concave surface at the center of the Fresnel concave lens-shaped transparent plate 606 forms a spherical surface centered on the projection lens 502, and the peripheral Fresnel surfaces BC, DE, FG, and H around it.
Each of I and JK is formed by a part of a spherical surface centered on the projection lens 502. Furthermore, planes AB, CD,
EF, GH, IJ, KL are projection lenses 50
It is formed in a shape such that it becomes the center of 2.

The projection screen 600 is connected to and held by a housing (not shown) via a flat outermost portion 607 of a Fresnel concave lens-shaped transparent plate 606.

Here, in this embodiment, as in Embodiment 1, if an optical system for forming a secondary light source in the projection lens 502 is used, as shown in FIG.
Principal rays emitted from each point of the optical image 217 formed on the 214 and 215 pass through the center of the projection lens 502.
After that, a part of the chief ray is incident vertically on the concave portion at the center of the Fresnel concave lens-shaped transparent plate 606, goes straight as it is, and forms an image on the diffusion surface 601. In addition, since the chief ray incident on the Fresnel surface at the periphery of the concave portion also enters perpendicularly at each incident point, it similarly proceeds straight and forms an image on the diffusion surface 601. The principal ray from the outermost peripheral portion of the optical image 217 is incident near a flat outermost peripheral portion 607 which is a connection portion of the Fresnel concave lens-shaped transparent plate 602 with the housing. An image is formed at the outer peripheral portion. Therefore, when the projection screen 600 is viewed from the direction opposite to the projection direction, the composite image of the optical images formed on the various liquid crystal light valves is projected and displayed on the entire surface of the projection screen 600 without distortion.

As described above, when the concave lens-shaped transparent plate 606 having a Fresnel surface is used as the projection screen section 600, the projection screen section can be made thinner in addition to the same effects as in the first embodiment, and the projection type A large-screen display device with a reduced display device can be provided.

Embodiment 3 FIG. In the projection optical system according to the first embodiment, the plano-convex lens 218 is connected to the liquid crystal light valve 21.
3, 214, and 215, which are closely attached to the incident light side, light beams emitted almost in parallel from the halogen lamp 201 are condensed on the projection lens 502, and the image of the light source (secondary light source) is incident on the entrance pupil of the projection lens 502. Examples of what to make are given. However, when the light emitted from the halogen lamp 201 almost in parallel and transmitted through the liquid crystal light valves 213, 214, and 215 is incident on the projection lens 502 as parallel light, in a so-called telecentric projection optical system, a concave lens-shaped transparent plate 602 is used. Is as shown in FIG. FIG. 9 is a cross-sectional view taken along the line I-O-I in FIG. 3. In this embodiment, the shape of the concave surface of the concave lens-shaped transparent plate 602 is a spherical surface centered on the rear focal point F ′ of the projection lens 502. .

In FIG. 9, various liquid crystal light valves 213, 2
Principal rays emitted from the respective points of the optical image 217 formed on the optical lenses 14 and 215 enter the projection lens 502 as parallel rays. Thereafter, the light is refracted, passes through the rear focal point F ′ of the projection lens 502, enters vertically at the concave surface of the concave lens-shaped transparent plate 602, advances straight as it is, and forms an image on the diffusion surface 601.
The principal ray from the outermost peripheral portion of the optical image 217 is incident on the concave lens-like transparent plate 602 near the connection with the housing,
Moving straight from this portion, an image is formed at the outermost peripheral portion of the diffusion surface 601. Therefore, when the projection screen 600 is viewed from the direction opposite to the projection direction, the composite image of the optical images formed on the various liquid crystal light valves is projected and displayed on the entire surface of the projection screen 600 without distortion.

As described above, the shape of the concave surface of the concave lens-like transparent plate 602 is determined by the optical axis even when the principal ray is incident on the projection lens in parallel or when the principal ray is inclined inward and passes through the center of the projection lens. It is needless to say that the principal ray enters the concave portion perpendicularly and has the same effect as in the above embodiment if the spherical surface has a center at the point of intersection.

Embodiment 4 FIG. In the first embodiment, an example in which the liquid crystal light valves 213, 214, and 215 of the optical image forming unit are of an active matrix type is shown, but a passive liquid crystal panel shown in FIG. 10 may be used. FIG.
In FIG. 5, reference numeral 131 denotes a lower glass substrate, 132 denotes an upper glass substrate, and 133 denotes a seal provided between the lower glass substrate 131 and the upper glass substrate 132 for sealing liquid crystal. Reference numeral 135 denotes a scanning transparent electrode provided in a stripe shape on the inner surface of the lower glass substrate 131, and reference numeral 136 denotes a display transparent electrode provided in a stripe shape orthogonal to the scanning transparent electrode 135 on the inner surface of the upper substrate 132. The display transparent electrode 136 is divided vertically by the upper substrate 132, and a display signal is applied from both upper and lower ends of the upper substrate 132.

Lower glass substrate 131, upper glass substrate 1
Polarizers (not shown) are provided on both sides of the base plate 32 so that the polarization axes are parallel to each other. Further, a retardation film (see FIG. (Not shown). A super-twisted nematic liquid crystal layer having a twist angle of 270 degrees is formed in a portion surrounded by the lower glass substrate 131, the upper glass substrate 132, and the seals 133.

For example, with such a configuration, a liquid crystal cell having the specifications shown in Table 1 and manufactured by Optrex Co., Ltd.
There is MF50124-NF-T (trade name), but DMF
When 50124-NF-T (trade name) is driven at a duty ratio of 1/32 by the voltage averaging driving method, and the amplitude voltage of the scan electrode driving waveform is changed, the change in the transmittance of the ON part and the OFF part is as follows. As shown in the characteristic diagram of FIG. FIG.
Reference numeral 1 denotes transmittance (%) on the vertical axis and applied amplitude voltage (V) on the horizontal axis. The ON portion is indicated by a solid line, and the OFF portion is indicated by a dotted line. As can be seen from the figure, when the applied amplitude voltage was about 10 V, a contrast ratio almost equivalent to that of the static drive was obtained, and the contrast ratio was 50.

In the above embodiment, the display transparent electrode 1 was used.
36 is divided vertically by the upper substrate 132
2 shows a configuration in which a display signal is applied from both upper and lower ends. However, the display transparent electrode is not divided vertically and may be driven at a duty ratio of 1/64. In this case, the number of external driver circuits can be reduced.

An inexpensive passive type liquid crystal cell as described above is
The projection display device 700 is configured by using the liquid crystal light valve in the first embodiment, and even if a large number of the
A large-screen display device having high luminance and high contrast can be configured at low cost.

Embodiment 5 FIG. In the above embodiment, the liquid crystal 3
Although the description has been made using the example of the plate light valve system, the same effect can be obtained by a single plate light valve system in which a color filter is provided in one liquid crystal cell. Further, as shown in FIG. 12, if the CRT projection tube 501 is used for the optical image forming unit and the other parts are configured in the same manner as in the first embodiment, the projection screen 60 can be used.
0 has an effect that an image can be projected and displayed on the entire surface without distortion.

Embodiment 6 FIG. FIG. 13 is a configuration diagram showing a cross section of a projection display device constituting a large screen display device according to still another embodiment of the present invention. The same or corresponding parts as in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. Reference numeral 301 denotes a red light source tube for emitting red light;
02 is a green light source tube for emitting green light, 303 is a blue light source tube for emitting blue light, and each color light source tube is a CRT type light source tube capable of emitting a single color. A plano-convex optical lens 304 is provided between each color light source tube 301, 302, 303 and each color light valve 213, 214, 215. The concave lens-shaped transparent plate 602 is the same as that shown in the third embodiment, and has a concave surface having a spherical surface centered on the rear focal point F ′ of the projection lens 502.

FIG. 14 is an enlarged view of the configuration around the light source tube of FIG. This figure shows, for example, a green light source tube 302 of a CRT system,
The blue light source tube 303 has the same configuration. 14, a front panel 306, a cylindrical side plate 307, and a rear plate 308 are shown.
Constitute a green light source tube 302, and the inside thereof is kept at a vacuum. The front panel 306 has a fluorescent screen 3
41 is applied, the surface thereof is coated with an aluminum back 351 as a high voltage electrode for acceleration, and the back plate 308 is provided with an electron gun 340 for forming an over-focused electron beam 347. Here, the fluorescent screen 341 is provided with the blue light source tube 30.
1, ZnS: Ag, Cl is used, and the green light source tube 30 is used.
In No. 2, ZnS: Au, Cu, Al is used, and in the red light source tube 303, Y ₂ O ₂ S: Eu ³⁺ is used. 3
Reference numeral 09 denotes a plano-convex lens formed by acrylic molding, and the fluorescent screen 341 is positioned near the focal length of the lens. 310 is a transparent adhesive, which is a plano-convex lens 3
09 and the front panel 306 are bonded together without an air layer.

An image corresponding to a video signal is formed on the liquid crystal light valve 214. Here, the area of the fluorescent screen 341 as a light emitting section is provided so as to be smaller than the area of the image forming section 217 of the liquid crystal light valve 214, and the electron beam 347 from the electron gun 340 receives the fluorescent screen 341. Is applied to the entire surface of the substrate. When all of the electron beam 347 is irradiated on the entire phosphor screen 341, if the current value of the over-focused electron beam 347 is constant, the smaller the area of the phosphor screen 341, the higher the electron density incident on the phosphor screen 341. As a result, the emission luminance of the phosphor screen 341 increases.
In this way, the fluorescent screen 341 having a small area located at the focal length of the plano-convex lens 309 emits light with extremely high luminance.

Here, when viewed microscopically, there is a space having a refractive index of 1 between the phosphor screen 341 and the entire panel 306.
Therefore, the light emitted from the central portion of the fluorescent screen 341 emitted with high luminance is emitted to the entire half space of the space between the entire panel 306 and the fluorescent screen 341 immediately after the emission of the fluorescent screen 341.
Immediately incident on the entire panel 306. These light fluxes have a half apex angle φ ｛φ = sin ⁻¹ (1 / n): n travels in a cone of refractive index の of the entire panel 306.

Of the total light beam traveling inside the cone having the half vertex angle φ, the light beam traveling within the cone having the half vertex angle θ is the front panel 30.
6. Since the transparent adhesive 310 and the plano-convex lens 309 have almost the same refractive index, the straight-advancing
After the light is emitted, the light becomes closer to parallel light,
4 enters the image forming unit 217. Thereafter, as shown in FIG. 13, most of the light enters the combining prism 216 and the projection lens 502. The principal ray incident on the projection lens 502 as a parallel ray is then refracted, passes through the rear focal point F ′ of the projection lens 502, enters the concave lens portion of the concave lens-shaped transparent plate 602 at right angles, and proceeds straight as it is to the diffusion surface 601. Image. The principal ray from the outermost peripheral portion of the optical image 217 enters the vicinity of the portion where the concave lens-shaped transparent plate 602 is connected to the housing.
The image is formed at the outermost peripheral portion of. Therefore, the projection screen 60
When 0 is viewed from the opposite direction of the projection direction, the composite image of the optical images formed on the various liquid crystal light valves is projected and displayed on the entire surface of the projection screen 600 without distortion.

As described above, according to this embodiment, all the light beams emitted from the phosphor screen to the half space are condensed in a cone having a half apex angle φ. The ratio of light reaching from 217 to the projection screen increases, and the light use efficiency becomes very high.

Here, the luminous efficiency of the phosphor by electron beam excitation is 500 lm / W with ZnS: Au, Cu, Al of the green light source tube, and 3 luminous efficiency of the halogen lamp.
It is at least 10 times higher than 0 lm / W.

As described above, the optical image forming section is constituted by the light valve on which an image is formed in accordance with a video signal, and the light source tube having the phosphor layer which emits light by electron beam excitation. Of the light emitted from the phosphor that emits light with low power consumption and high brightness to the entire half space with a lens, and the light valve and projection By guiding the light to the lens, the light use efficiency can be increased.

Therefore, if a large-screen display device is constructed by arranging a large number of the above-mentioned projection display devices, the amount of heat generated from the light source section is extremely small, a heat-radiating fan is not required, the power consumption is small, the thickness is small and the height is high. A large-screen display device capable of displaying luminance can be realized.

Embodiment 7 FIG. FIG. 15 shows that in the sixth embodiment,
FIG. 9 is a configuration diagram illustrating a CRT type light source tube according to still another embodiment. Reference numeral 312 denotes a plano-convex lens-shaped front panel, which is manufactured by glass cutting or molding such that molten glass is poured into a carbon mold having a desired shape. The plano-convex lens-shaped front panel 312, cylindrical side plate 307, and back plate 308 constitute a CRT type light source tube 313 whose inside is kept vacuum. In FIG. 15, FIG.
The same or corresponding parts are denoted by the same reference numerals and description thereof is omitted.

This embodiment operates in the same manner as the sixth embodiment and has the same effects. Further, in the seventh embodiment, since the front panel portion is formed integrally with the lens, the adhesive layer as in the sixth embodiment becomes unnecessary, and the reflection at each interface is completely eliminated, so that light loss can be prevented. Become. Also,
In the manufacturing process, the step of bonding the front panel and the acrylic lens as in the sixth embodiment is not required, so that the process is simplified and there is no possibility of misalignment when bonding the acrylic lens.

Embodiment 8 FIG. FIG. 16 shows the individual light source tubes 301, 302, 3 for red, blue, and green in FIG.
FIG. 3 is a perspective view showing an example in which the liquid crystal light valves 03 and liquid crystal light valves 213, 214, and 215 are integrated. In FIG. 16, reference numeral 216 denotes a dichroic prism that combines red light, green light, and blue light; 400, a three-color light source tube that emits red light, green light, and blue light; and 420, an active matrix liquid crystal light valve that modulates light. , A red image display unit 421R, a green image display unit 421G, and a blue image display unit 421B. Reference numeral 435 is a mirror that reflects light, and 502 is a projection lens that projects synthesized light. The liquid crystal light valve 420 and the three-color light source tube 400 are closely adhered by a transparent adhesive 436 without an air layer.

FIG. 17 is a pattern diagram showing the liquid crystal light valve 420. Reference numeral 422 denotes an upper glass substrate, and 423 denotes a lower glass substrate. A liquid crystal is applied between the two glass substrates and sealed therein. The lower glass substrate 423 includes a display signal line 424 and a scanning line 42.
6 are arranged so as to be orthogonal to each other, and a pixel electrode 428 is connected to the intersection through a thin film transistor (not shown). An external signal is applied to the display signal line 424 via the display signal terminal 425, and an external signal is applied to the scan line 426 via the scan signal terminal 427. Further, on the inner surface of the upper glass substrate 422, a counter electrode composed of a transparent electrode is provided.

A red image display portion 421R, a green image display portion 421G, and a blue image display portion 421B are formed by a set of pixel electrodes 428. As in the sixth embodiment, the three image display portions are formed by a projection screen (not shown). )) To combine one image. Corresponding pixel electrode 4 of each of three image display units constituting each point synthesized on the projection screen
28 is located at an equal distance from point 0 as shown in FIG. That is, the pixels corresponding to the corners on the screen correspond to the pixel electrodes Qr in the red image display unit 421R, the pixel electrodes Qg in the green image display unit 421G, and the pixel electrodes Qb in the blue image display unit 421B. Pixels corresponding to some points of the character on the screen are the pixel electrode Pr and the green image display 421 in the red image display 421R.
G corresponds to the pixel electrode Pg, and the blue image display portion 421B corresponds to the pixel electrode Pb, and the pixel electrodes Qr, Qg, Qb have the point 0.
Located equal distance from, the pixel electrode Pr, Pg, Pb is also located at an equal distance from the point 0. In other words, each point of the three image forming units constituting an arbitrary point of the optical image synthesized and displayed on the projection screen is located on the circumference around the point 0. Further, the center point of the light synthesis of the dichroic prism 216 in FIG. 16 is arranged so as to be located directly above the point 0.

FIG. 18 is a perspective view showing the outer shape of the three-color light source tube 400. FIG. 19 is a perspective view of the three-color light source tube 400 shown in FIG.
FIG. 3 is a sectional view taken along line I-III. In FIG. 18, a three-color light source tube 400 includes a front panel 402, a rear panel 403, and a side panel 4.
The front panel 402 is formed of a vacuum vessel as a glass tube which is hermetically sealed with a fluorescent material layer 04. On the inner surface of the front panel 402, a phosphor layer 406 illuminating in each of red (R), green (G), and blue (B) colors is provided. Light emitting units 405R and 405 composed of
G, 405B. Here, as shown in FIG. 16, when the liquid crystal light valve 420 is overlaid on the front panel 402 of the three-color light source tube 400, the three light emitting units 405R, 405G, and 405B
Red image display unit 421R, green image display unit 421G,
The blue image display unit 421B is provided so that light of a corresponding color is entirely incident on the blue image display unit 421B.

As shown in FIG. 19, the light-emitting portions 405R, 405G, 40
5B, three electron guns 408 for irradiating the entire surface of the phosphor layer 406 with the unfocused electron beam 407, respectively.
(Two not shown) are provided. 409, 41
Reference numerals 0 and 411 denote a heater, a cathode, and a grid which constitute the electron gun 408, respectively. Also, the phosphor layer 406
Is ZnS: Ag, Cl in blue, and ZnS:
Au, Cu, and Al are used in red, and Y ₂ O ₂ S: Eu ³⁺ is used in red. An aluminum back 412 as an anode for applying a high voltage is applied to the surface of each phosphor layer 406.

Hereinafter, the operation will be described. First, FIG.
At 9, a high voltage of more than ten kilovolts is applied to the aluminum back 412, and a negative voltage is applied to the grid 411 with respect to the cathode 410. At the same time, a predetermined current is applied to the heater 409 to heat the cathode 410 and to apply the voltage of the grid 411 to the cathode 410.
When the potential is approached, the electron beam 407
Is emitted toward the phosphor layer 406. The electron beam 407 has an unfocused beam 407 having a predetermined spread (θ) depending on various conditions such as the diameter of a hole provided in the center of the grid 411, the distance between the grid 411 and the cathode 410, and the anode voltage of the aluminum back 412. Phosphor layer 4
06 is accelerated. Here, the phosphor layer 406 emits high-luminance light of a color corresponding to the phosphor of each of the light emitting units 405R, 405G, and 405B.

Thereafter, the red light emitting section 4 of the three-color light source tube 400
The red light emitted from 05R, as shown in FIG.
After being modulated by passing through the red image display portion 421R on which the image of the red component of the liquid crystal light valve 420 placed in close contact is displayed, the light is reflected by the mirror 435 in the right angle direction, and further reflected by the dichroic prism 216 in the right angle direction. Is reflected. The green light emitted from the green light emitting unit 405G is similarly transmitted through the green image display unit 421G on which the image of the green component is displayed, modulated, and then reflected by the mirror 435 in the right-angle direction, and is reflected by the dichroic prism 216. It is transmitted as it is. The blue light emitted from the blue light emitting unit 405B is transmitted through the blue image display unit 421B on which the image of the blue component is displayed and modulated, and then reflected by the mirror 435 in the right angle direction, and also by the dichroic prism 216 in the right angle direction. Is reflected by In this way, the three color images synthesized by the dichroic prism 216 are enlarged and projected by the projection lens 502 and displayed on the screen. In this embodiment, an example in which the electron gun 408 is based on thermionic emission is shown, but it goes without saying that the electron gun 408 may be based on field emission or photoelectron emission.

Here, the red image and the blue image are
35 is reflected twice by the dichroic prism 216, but the green image is reflected only once by the mirror 435, so that the image on the green image display unit 421G becomes the image on the red image display unit 421R and the image on the blue image display unit 421B. On the other hand, the liquid crystal light valve 420
An image is displayed on each of them.

As described above, in this embodiment, since the light source tubes for emitting the three colors of light are housed in one container, the projection display device is reduced in size, and the large-screen display device in which these are arranged is reduced in thickness. You. Also, by adjusting the potential of the grid 411 of each color, it is possible to independently adjust the luminance of each of the red, green, and blue color components of the image on the projection screen, so that chromaticity adjustment such as white balance can be easily performed. Can be done. Further, since the three color light emitting units and the image forming unit are integrally arranged on the same plane, optical alignment can be achieved with an adjustment mechanism that can adjust only one light source tube. An inexpensive, small and highly reliable projection display device and a large-screen display device in which these are arranged can be realized.

Further, the three color image display sections 421R, 421R,
Since the optical distances from 21G and 421B to the image combining point of the dichroic prism 216 are configured to be equal, the optical distances to the projection lens 502 are also equal, and the magnification and the imaging distance between the projection lens 502 and the projection screen are also equal. Thus, high-quality display becomes possible.

Embodiment 9 FIG. FIG. 20 is a partial sectional view showing a large screen display device according to Embodiment 9 of the present invention. In this example, a condenser lens is provided between the light source tube and the liquid crystal light valve in Example 8 to increase the light use efficiency.
It has a configuration in which projection display devices are stacked.

In FIG. 20, the concave lens-shaped transparent plate 60 is used.
2. The diffusion surface 601 is the same as that in the first embodiment. Also, a projection lens 502, a mirror 435, a dichroic prism 216, a liquid crystal light valve 420
Is similar to that of the eighth embodiment, and is provided at the center of the housing 505 so that the optical axis of the projection lens 502 matches the center of the projection screen 600. Reference numeral 431 denotes a three-color light source tube whose structure is similar to that of FIG. FIG.
FIG. 4 is a perspective view showing a color light source tube 431. A light emitting unit 405R,
405G and 405B are smaller than the size of the image forming portion of the liquid crystal light valve 420 (the dotted line portion in the figure), and are configured to increase the electron beam irradiation density. Further, the three-color light source tube 431 is provided at an upper portion of the housing 505. 433 is a plano-convex lens,
5, the convex portions of which are located at each image forming portion of the liquid crystal light valve 420. Reference numeral 434 denotes a transparent elastic body, which is applied to the front panel 402 having the light emitting surface of the three-color light source tube 431. This transparent elastic body 43
As No. 4, for example, a two-liquid addition reaction type silicone RTV resin (trade name KE1603A / B, manufactured by Shin-Etsu Chemical Co., Ltd.)
Is used.

Reference numeral 432 denotes a three-color light source tube of the lower projection display device, and reference numeral 437 denotes a transparent elastic member provided on the surface of the three-color light source tube 432. Also, the three-color light source tube 431 of the housing 505
A hole is provided in the upper part where the lens is located and the lower part where the plano-convex lens 433 is located. Similarly, the lower surface of the housing 505 and the plane portion of the plano-convex lens 433 are provided so as to be substantially coplanar. Thus, when the projection display devices are stacked, the three-color light source tube 432 of the lower projection display device
The front panel 402 and the plane portion of the plano-convex lens 433 of the upper projection display device are in close contact with each other with a transparent elastic body 437 almost without an air layer.

In this embodiment, the minute light-emitting portions 405R, 405G, and 4 of the three-color light source tube 432 of the lower projection display device
05B emits light with high luminance by an electron beam having a high current density. Most of the emitted light of each color is converted into substantially parallel light by the plano-convex lens 433 of the upper projection display device, and most of the light is converted to the liquid crystal light valve 420 and the mirror 43.
5, dichroic prism 216, projection lens 502
Incident on. The principal ray incident on the projection lens 502 as a parallel ray is refracted thereafter, and the projection lens 502
After passing through the rear focal point F ′, the light is vertically incident on the concave surface of the concave lens-shaped transparent plate 602, goes straight as it is, and forms an image on the diffusion surface 601. The principal ray from the outermost peripheral portion of the optical image is incident near the portion where the concave lens-shaped transparent plate 602 is connected to the housing, but goes straight from this portion and forms an image at the outermost peripheral portion of the diffusion surface 601. Therefore, when the projection screen 600 is viewed from the opposite direction of the projection direction, the composite image of the optical image formed on the liquid crystal light valve 420 is projected and displayed on the entire surface of the projection screen 600 without distortion.

As described above, in this embodiment, the projection lens 502 and the synthetic optical system are arranged at the center of the housing 505 of the projection display apparatus, and the three-color CRT light source tubes 431 are arranged above and below them.
And a plano-convex lens 433 for condensing light, the light use efficiency can be improved and the device can be downsized.

In the above embodiment, an example was described in which the light from the light source of the lower projection display device was incident on the light valve of the upper projection display device. Needless to say, the same effect can be obtained even when a projection optical path is formed between the projection display devices adjacent to each other on the left and right.

Embodiment 10 FIG. FIG. 22 shows Embodiment 1 of the present invention.
FIG. 3 is a configuration diagram illustrating a cross section of a projection screen unit according to a first embodiment.
Reference numeral 505 denotes a housing; 600, a projection screen; a concave lens-shaped transparent plate 603 having a Fresnel surface 701 having a convex lens effect formed on the surface;
02. Reference numeral 704 denotes a transparent elastic layer, which is thinly applied around the projection screen 600 part. In this embodiment, the transparent elastic layer 704 is made of, for example, a two-liquid addition reaction type silicone RTV resin (trade name K, manufactured by Shin-Etsu Chemical Co., Ltd.).
E1603A / B). FIG. 23 is a front view showing the lenticular panel 702. The lenticular panel 702 is a sheet in which the semi-cylindrical lenses 703 and the black stripes 714 are alternately continuous, and an appropriate diffusing agent is mixed in the semi-cylindrical lenses 703. Further, the width of the lenticular panel 702 is a positive multiple of the pitch of the black stripes 714, and the width of the black stripes 714 is half that of the other two at both ends.

In this embodiment, as shown in FIG. 22, light having a spread from a projection lens (not shown) is perpendicularly incident on the concave surface of the concave lens-shaped transparent plate 603, and is refracted by the Fresnel surface 701 to be substantially refracted. After becoming parallel light, the light enters the lenticular panel 702 and is spread in the horizontal direction. As a result, when the projection screen surface is viewed, the brightness of the front surface becomes uniform, and the viewing angle in the horizontal direction is expanded. Although a conventional projection display apparatus uses a Fresnel lens panel and a lenticular panel for these purposes, as in this embodiment, a concave lens-shaped transparent plate 6 is used.
By forming the surface of No. 03 directly on the Fresnel surface, the concave lens-shaped transparent plate 603 and the Fresnel surface 701 are not displaced from each other. The portions are joined with high precision, and the image quality of the array joining portion does not deteriorate.

As shown in FIG. 23, both ends of the lenticular panel 702 are black stripe portions, and the width thereof is half that of the other portions. When the projection screens are arranged in the same manner, the arrangement joining portion of the projection screen portion becomes a black stripe portion, and even if there is a slight gap at the joining portion of the projection screen, it is inconspicuous and image quality does not deteriorate.

Further, as shown in FIG. 22, since the transparent elastic layer 704 is thinly applied around the projection screen 600, when the projection type display devices are arranged in a matrix, the arrangement joining portion of the projection screen is transparent. The elastic layers 704 are closely bonded to each other without an air layer, and the discontinuous surface of the refractive index is eliminated. Therefore, there is no reflection of external light or projection light at the arrangement joining portion of the projection screen portion, and the image quality does not deteriorate.

Embodiment 11 Embodiment 10 describes the case where the concave lens-shaped transparent plate 603 is used as a means for projecting and displaying the optical rubber of the optical image forming section on the entire surface of the projection screen.
4 may be adopted. That is, a lenticular panel 702 on the viewing surface side is used as the projection stalline 600.
A Fresnel panel 604 having a concave lens effect is formed on the surface of the Fresnel panel 604, and a Fresnel surface 701 having a convex lens effect is formed on the surface of the Fresnel panel 604. It has something. The above-described embodiment the same way also be configured in this manner
Has the effect of

Embodiment 12 FIG. Further, as shown in FIG. 25, the projection screen 600 may be configured by laminating a lenticular panel 702 on the viewing surface side and a transparent plate 605 having a Fresnel surface 701 having a convex lens effect on the surface. However, in this case, the thickness of the housing 505 is d, the incident angle of the principal ray corresponding to the outermost peripheral portion of the optical image of the optical image forming unit (light valve) to the transparent plate 605 is θ, and the refractive index of the transparent plate 605 is When np
The thickness t of the transparent plate 605 needs to satisfy t = d (np ² / sin ² θ−1) ^1/2 .

Embodiment 13 FIG. Further, as shown in FIG. 26, a projection screen 600 is formed by distributing a lenticular panel 702 on the viewing surface side and a distributed refractive index plate 608 having a Fresnel surface 701 having a convex lens effect on the surface.
May be bonded together. In other words, as shown in FIG. 26, the distributed refractive index plate 608 has the lowest refractive index at the center, and increases in proportion to the square of the distance (x) from the center to the periphery. It is a flat plate and is manufactured by a diffusion polymerization method of plastics having different refractive indexes. This produces the same effect as the concave lens-shaped transparent plate.

[0088]

As described above, according to the first aspect of the present invention, the optical image forming unit for forming the optical image by modulating the light emission intensity in the two-dimensional space according to the video signal, and enlarging the optical image. A projection display system comprising a projection optical system for projecting, a housing for housing and supporting the optical image forming unit and the projection optical system, and a screen unit for projecting and displaying an optical image enlarged by the projection optical system,
In a large screen display device arranged in a matrix, a surface of the screen portion on the side of the projection optical system has a concave portion having a spherical shape centered on an intersection of a principal ray and an optical axis of the projection optical system, and The screen and the housing are connected via the surface of the screen unit on the side of the projection optical system, so that the optical image of the optical image forming unit is projected and displayed on the entire surface of the screen on the observation surface without distortion. Even if many projection display devices are combined, there is an effect that a large-screen display device which can prevent non-display portions and distortion from occurring can be obtained.

Further, according to the second aspect of the present invention, an optical image forming unit for forming an optical image by modulating the light emission intensity in a two-dimensional space according to a video signal, and a projection optical system for enlarging and projecting the optical image. A plurality of projection display devices comprising a system, a housing for housing and supporting the optical image forming unit and the projection optical system, and a screen unit for projecting and displaying an optical image enlarged by the projection optical system. In the large-screen display device arranged, a projection unit for projecting projection light onto the entire screen surface is provided on the surface of the screen unit on the side of the projection optical system, and a Fresnel surface is formed on the side opposite to the projection optical system side. Observes the optical image of the optical image forming unit by providing a transparent plate and connecting the screen unit and the housing via the surface of the screen unit on the side of the projection optical system
Projection display without distortion on the entire screen surface on the front side
Can be combined with many projection display devices
Also, it is possible to prevent non-display portions and distortion from occurring.

According to the third aspect of the present invention, the optical image forming section comprises a light valve on which an image is formed in accordance with a video signal, an electron beam generating means, and a phosphor layer which emits light by electron beam excitation. By providing a light source tube having a light-emitting portion, a thin large-screen display device capable of high-brightness display with low heat generation from the light source portion, no heat-radiating fan, low power consumption, in addition to the above effects can be obtained. effective.

According to the fourth aspect of the present invention, the light emitting portion area of the light source tube is made smaller than the light valve area, and the side of the light source tube facing the light valve is formed as a convex lens. In addition, there is an effect that a thin large-screen display device capable of high-luminance display with low power consumption can be obtained.

Further, according to the fifth aspect of the present invention, in one container, a light source having an electron beam generating means and a plurality of light emitting portions each composed of a phosphor layer which emits a different color when excited by an electron beam. The provision of the tubes has the effect of reducing the size of the projection display devices and obtaining a large-screen display device that can be arranged and thinned.

According to the sixth aspect of the present invention, the frame
Black stripe on the side opposite to the projection optical system side of the
Install a lenticular panel with
The width of the black panel
Integer multiples, and the width of the upper black stripe is
The projection type table is constructed by halving the others.
When the display devices are arranged in a matrix, the projection screen
Black stripes at the junction of the
This has the effect of preventing the formation.

According to the seventh aspect of the present invention, since the light valve is formed of a passive liquid crystal panel, in addition to the above-mentioned effects, there is an effect that a large-screen display device which can be manufactured at a lower cost than the conventional device can be obtained. is there.

According to the eighth aspect of the present invention, since the transparent elastic body applied to the peripheral part of the screen part is provided, the joint part of the screen part when the projection display device is arranged is a transparent elastic body. There is an effect that a large-screen display device can be obtained in which the surfaces are in close contact with each other, the discontinuous surface of the refractive index is eliminated, and the reflection of external light and projection light at the joints of the screen array is eliminated, thereby preventing the deterioration of image quality.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a cross section of a projection display device constituting a large-screen display device according to Embodiment 1 of the present invention.

FIG. 2 is a front view showing a liquid crystal light valve of the projection display apparatus according to Embodiment 1 of the present invention.

FIG. 3 is a perspective view showing a projection screen unit of the projection display device according to the first embodiment of the present invention.

FIG. 4 is a cross-sectional view illustrating a projection screen of the projection display device according to the first embodiment of the present invention.

FIG. 5 is a perspective view showing a multi-type large-screen display device in which the projection display devices according to the first embodiment of the present invention are arranged in a matrix of many rows and columns.

FIG. 6 is a perspective view showing a projection screen of a projection display apparatus according to Embodiment 2 of the present invention.

FIG. 7 is a cross-sectional view illustrating a projection screen section of a projection display apparatus according to Embodiment 2 of the present invention.

FIG. 8 is an enlarged configuration diagram showing an end of a projection screen of a projection display apparatus according to a second embodiment of the present invention.

FIG. 9 is a cross-sectional view illustrating a projection screen of a projection display apparatus according to Embodiment 3 of the present invention.

FIG. 10 is a front view showing a liquid crystal light valve of a projection display apparatus according to Embodiment 4 of the present invention.

FIG. 11 is a characteristic diagram illustrating a relationship between an applied amplitude voltage and a transmittance of a liquid crystal light valve of the projection display apparatus according to the fourth embodiment of the present invention.

FIG. 12 is a configuration diagram showing a cross section of a projection display apparatus according to Embodiment 5 of the present invention.

FIG. 13 is a configuration diagram showing a cross section of a projection display apparatus according to Embodiment 6 of the present invention.

FIG. 14 is a configuration diagram showing a cross section around a light source tube of a projection display apparatus according to Embodiment 6 of the present invention.

FIG. 15 is a configuration diagram showing a cross section around a light source tube of a projection display apparatus according to Embodiment 7 of the present invention.

FIG. 16 is a perspective view showing a projection optical system of a projection display apparatus according to Embodiment 8 of the present invention.

FIG. 17 is a pattern diagram showing a liquid crystal light valve of a projection display apparatus according to Embodiment 8 of the present invention.

FIG. 18 is a perspective view showing a three-color light source tube of a projection display apparatus according to Embodiment 8 of the present invention.

FIG. 19 is a configuration diagram showing a cross section of a three-color light source tube of a projection display apparatus according to Embodiment 8 of the present invention.

FIG. 20 is a partial sectional view of a large-screen display device on which projection-type display devices according to Embodiment 9 of the present invention are stacked.

FIG. 21 is a perspective view showing a three-color light source tube of a projection display according to Embodiment 9 of the present invention.

FIG. 22 is a configuration diagram showing a cross section of a projection screen of a projection display apparatus according to Embodiment 10 of the present invention.

FIG. 23 is a front view showing a lenticular panel of a projection display apparatus according to Embodiment 10 of the present invention.

FIG. 24 is a configuration diagram showing a cross section of a projection screen of a projection display apparatus according to Embodiment 11 of the present invention.

FIG. 25 is a configuration diagram showing a cross section of a projection screen of a projection display apparatus according to Embodiment 12 of the present invention.

FIG. 26 is an explanatory diagram showing a cross section of a projection screen portion of a projection display apparatus according to Embodiment 13 of the present invention, together with a refractive index distribution.

FIG. 27 is a perspective view showing a multi-type large-screen display device in which projection-type display devices according to a conventional example are arranged in a matrix of many rows and columns.

FIG. 28 is a configuration diagram showing a cross section of a projection display device constituting a large-screen display device according to a conventional example.

[Explanation of symbols]

 213 liquid crystal light valve 214 liquid crystal light valve 215 liquid crystal light valve 216 dichroic prism 301 red light source tube 302 green light source tube 303 blue light source tube 309 plano-convex lens 312 plano-convex lens shaped front panel 400 three-color light source tube 406 phosphor layer 407 electron beam 408 electron Gun 420 Liquid crystal light valve 431 Three-color light source tube 432 Three-color light source tube 433 Plano-convex lens 434 Transparent elastic body 435 Mirror 502 Projection lens 505 Housing 600 Projection screen 601 Diffusion surface 602 Concave lens transparent plate 606 Fresnel concave lens transparent plate 700 Projection display Device 704 Transparent elastic layer

────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Shuji Iwata 8-1-1, Tsukaguchi-Honmachi, Amagasaki-shi, Materials and Materials Research Laboratory, Mitsubishi Electric Corporation (56) References JP-A-3-41429 (JP, A) JP-A-2-134677 (JP, A) JP-A-3-249633 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G03B 21/10 G03B 21/58

Claims (8)

(57) [Claims] An optical image forming unit configured to form an optical image by modulating light emission intensity in a two-dimensional space in accordance with a video signal; a projection optical system configured to project the optical image in an enlarged manner; A large-screen display device in which a plurality of projection display devices each including a housing for housing and supporting a projection optical system and a screen unit for projecting and displaying an optical image enlarged by the projection optical system are arranged in a matrix. A surface of the screen unit on the side of the projection optical system, having a concave surface portion having a spherical shape centered on the intersection of the principal ray and the optical axis of the projection optical system, and a surface of the screen unit on the side of the projection optical system A large-screen display device, wherein the screen unit and the housing are connected via a surface unit. 2. An optical image forming unit for forming an optical image by modulating light emission intensity in a two-dimensional space in accordance with a video signal, a projection optical system for enlarging and projecting the optical image, the optical image forming unit, In a large screen display device in which a plurality of projection display devices each including a housing for housing and supporting a projection optical system and a screen unit for projecting and displaying an optical image enlarged by the projection optical system are arranged in a matrix. A projection unit for projecting projection light onto the entire surface of the screen, on a surface of the screen unit on the side of the projection optical system;
A transparent plate having a Fresnel surface formed on the opposite side is provided, and the screen unit and the housing are configured to be connected via a surface portion of the screen unit on the projection optical system side. Large screen display device. 3. The optical image forming section includes a light valve having a light valve on which an image is formed in accordance with a video signal, an electron beam generating means, and a light source tube having a light emitting section including a phosphor layer which emits light by electron beam excitation. 3. The large-screen display device according to claim 1, wherein: 4. The large screen according to claim 3, wherein the light emitting tube has a light emitting portion area smaller than a light valve area, and a side of the light source tube facing the light valve is a convex lens. Display device. 5. An electron beam generating means in one container,
5. The large-screen display device according to claim 3, further comprising a light source tube having a plurality of light-emitting portions each formed of a phosphor layer that emits a different color when excited by an electron beam. 6. On the opposite side of the Fresnel surface from the projection optical system side,
Lenticular panel with black stripes
Install and adjust the width of the lenticular panel to the blacks
Make it an integral multiple of the pitch of the tripe, and
The width of the stripe is half that of the others.
3. The large-screen display device according to claim 2, wherein: 7. The large-screen display device according to claim 1, wherein the light valve is constituted by a passive liquid crystal panel. 8. The large-screen display device according to claim 1, wherein a transparent elastic body is provided in a peripheral portion of the screen portion.