JP2002162689A - Large screen display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a large screen display device of a high grade which is constituted by arraying a plurality of projection display devices and is capable of suppressing the generation of non-display parts between adjacent screens which are the cause for the deterioration of image quality and is capable of preventing curving of the large-size display screen in spite of a change in ambient temperature. SOLUTION: This large screen display device is arrayed with a plurality of the projection display devices 30 consisting of casings 20 housed and held with projectors 50 for forming optical images according to video signals and macroprojecting optical images and the screens 10 for displaying the optical images macroprojected by the projectors 50. The individual projection display devices 30 are constituted by abutting the peripheral parts of the screens 10 on the ends of the casings 20 and joining and fixing the screens 10 to the ends of the casings 20. The casings 20 and the screens 10 are composed of materials having nearly equal coefficients of thermal expansion and a plurality of the projection display devices are so arrayed that the adjacent screens come into tight contact with each other.

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 constituted by combining a plurality of projection display devices.

[0002]

2. Description of the Related Art FIG. 8 is a perspective view showing a schematic structure of a conventional large-screen display device constituted by combining a plurality of projection display devices. In the figure, 40 is a projection display device,
Reference numeral 10 denotes a screen of the projection display device 40, and reference numeral 41 denotes a gap between the screens of the adjacent projection display devices 40. As shown in FIG. 8, a conventional large-screen display device is configured by arranging a plurality of projection display devices 40 in a matrix so as to be stacked vertically and horizontally, and using a plurality of screens 10. Make up one large screen screen.

In FIG. 8, the projection display device 40 is vertically
One large display screen is constructed by arranging three rows horizontally and one row, and the video signal is enlarged three times vertically and horizontally, and each screen 10 of each projection display device 40 has one screen.
A corresponding part of the screen is enlarged and displayed. FIG. 9 is a configuration diagram showing a cross section when two projection display devices 40 in FIG. 8 are arranged side by side in the vertical direction.
In the drawing, reference numeral 50 denotes a projection device serving as a projection optical system;
1 is a light beam from the outermost periphery of the optical image emitted from the projection device 50, 10 is a screen, 20 is a housing for housing and holding the projection device 50 and the screen 10, and 60 is a housing for the peripheral portion of the screen 10. An opaque tape (for example, a black tape) having an adhesive property for abutting and fixing to an end of the tape 20.

[0004] The conventional large-screen display device, as described above,
A plurality of projection display devices are stacked and arranged in a matrix so that the plurality of screens 10 form one plane to form one large screen screen. However, when the ambient temperature rises during operation, distortion occurs due to the difference in the coefficient of thermal expansion between the housing 20 and the screen 10, and the display screen formed as one large screen may be curved. In order to avoid this, a gap 41 having a width of about 1 mm is provided in advance between the individual screens 10 as shown in FIG. The gaps 41 are similarly provided between the screens 10 as shown in FIG. 8 when the individual screens 10 are vertically stacked as shown in FIG. 9 or when they are arranged side by side.

FIG. 10 shows a screen 10 and a housing 2.
FIG. 10 is an enlarged view of a joint portion (portion A indicated by a broken-line circle in FIG. 9) with an end portion of the housing 20. A step H1 is formed in the outer peripheral portion, and the inner peripheral portion of the end portion of the housing 20 is arranged such that the light beam 51 from the outermost peripheral portion of the optical image emitted from the projection device 50 passes through the screen 10, A step H2 is formed in the inner peripheral portion of the outermost surface of the screen 10 (i.e., the outermost peripheral portion of the screen 10).

[0006]

Since the conventional large-screen display device is configured as described above, when a large number of individual projection-type display devices 40 are combined and arranged for projection, a gap 41 between the screens 10 is reduced. Since there is no light emission, vertical and horizontal stripe-shaped non-display portions are generated, and the ends of the screen 10 and the housing 20 are joined and fixed using an opaque tape 60 that does not reflect light. When the screen is viewed from an oblique direction, an unsightly black line appears on the non-display portion, and when an image is displayed as one large display screen, the image quality of the display screen is significantly deteriorated. In addition, when the ambient temperature rises during operation, distortion occurs due to the difference in the coefficient of thermal expansion between the housing 20 and the screen 10, and there is a problem that the screen formed as one large screen is curved.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-described problem. In a large-screen display device in which a plurality of projection-type display devices are arranged to form one large-screen display screen, the image quality is improved. A high-quality large-screen display device that can suppress the occurrence of non-display portions between screens that cause deterioration, and can prevent the curvature of a display screen configured as one large screen even when the ambient temperature changes. It is intended to provide.

[0008]

A large-screen display device according to the present invention forms an optical image in accordance with a video signal, and accommodates and holds a projection device for enlarging and projecting the optical image.
In a large-screen display device in which a plurality of projection display devices including a screen that displays an optical image enlarged and projected by the projection device are arranged, the individual projection display devices include:
The peripheral portion of the screen is brought into contact with the end of the housing, and the screen is joined and fixed to the end of the housing. The housing and the screen are made of materials having substantially equal thermal expansion coefficients, and the adjacent screen is A plurality of projection type display devices are arranged so that they are in close contact with each other.

Further, a large-screen display device according to the present invention comprises:
A projection-type display that forms an optical image according to a video signal and houses and holds a projection device that enlarges and projects the optical image, and a screen that displays the optical image enlarged and projected by the projection device. In a large-screen display device in which a plurality of devices are arranged, each projection display device is configured such that the peripheral portion of the screen is brought into contact with the edge of the housing, and the screen is attached to the edge of the housing using a transparent tape. And fixed to the
A plurality of projection display devices are arranged such that adjacent screens are in close contact with each other via the transparent tape.

Further, in the large-screen display device according to the present invention, the housing and the screen constituting the projection display device are made of a material having substantially the same thermal expansion coefficient.

Further, in the projection display device of the large screen display device according to the present invention, the transparent tape for joining and fixing the screen to the end of the housing is provided with irregularities on its outer surface. It is assumed that.

Further, in the projection type display device of the large screen display device according to the present invention, after the light rays from the outermost peripheral portion of the optical image emitted from the projector pass through the screen, the outermost peripheral surface of the screen is exposed. The end of the projection type display device is formed so that an image is formed at a portion.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the drawings. Note that the same reference numerals as those in the conventional drawings indicate that they are the same as or equivalent to the conventional ones. Embodiment 1 FIG. FIG. 1 is a perspective view of a projection type display device constituting a large screen display device according to an embodiment of the present invention.
FIG. 3 is a configuration diagram showing a cross-section when a table is stacked,
gital Light Processing) method.

In the drawing, 1 is a light source, 2 is a reflector having a parabolic shape, for example, which is disposed so as to surround the light source 1, 3 is a lens of an incident optical system, and 4 is disposed in front of a lens 3 of the incident optical system. DMD (Digital Micromirror Devi)
ce) 5 is a lens of the projection optical system,
Is composed. Reference numeral 10 denotes a screen, and 20 denotes a housing. The housing 20 is a projection device 5 including a light source 1, a reflector 2, an incident optical system 3, a DMD 4, and a projection optical system 5.
The screen 10 is fixed by an opaque tape 60 having an adhesive property at its end while accommodating the screen 10.

Reference numeral 30 denotes a substantially rectangular projection type display device comprising the screen 10, the housing 20, the projection device 50 and the like. The projection device 50 as a projection optical system
Forms an optical image in accordance with an input video signal, and enlarges and projects the optical image on a screen 10. Each screen 10
Are in contact with the ends of the corresponding housings 20, respectively, and are joined and fixed by an opaque tape 60 having an adhesive property. And adjacent individual screens 1
The zeros are arranged without gaps via an opaque tape 60, forming one large display screen.

Since the opaque tape 60 for bonding and fixing the casing 20 and the screen 10 is thin, there is no need to provide a step at the outer peripheral portion of the end of the casing 20. By providing a slight step corresponding to the thickness, the side surfaces of the adjacent projection display devices 30 (that is, the side surfaces of the housing 20) can be completely adhered without any gap. After the light beam 51 from the outermost peripheral portion of the optical image emitted from the projection device 50 passes through the screen 10,
A step H2 is formed at the inner peripheral portion of the outermost surface of the screen 10 so as to form an image at the outermost peripheral portion (that is, the outermost portion of the screen 10). The shape of the inner peripheral portion of the end of the housing 20 may be an inclined surface instead of a right-angled notch having a step H2.

FIG. 2 is a diagram showing components of the screen 10. The screen 10 includes a lenticular sheet 110 on the outermost surface, a Fresnel lens sheet 120 on the back side, and a reinforcing plate 130 on the back side as viewed from an observer. Although not shown, a front sheet made of an acrylic resin may be installed on the front surface of the lenticular sheet 110 of the screen 10 (that is, on the viewer side).

The lenticular sheet 110 is formed with a lenticular lens 111 having a vertical stripe shape and a black stripe 112. The Fresnel lens sheet 120, the lenticular sheet 110, and the reinforcing plate 130 constituting the screen 10 are mainly made of acrylic resin. The housing 20 of the large-screen display device according to the present embodiment shown in FIG. 1 is made of glass fiber reinforced plastic having a thermal expansion coefficient substantially equal to that of the acrylic resin forming the screen 10. It is installed closely so that there is no gap between matching housings.

Hereinafter, the operation of the projection display device constituting the large screen display device according to the first embodiment will be described with reference to FIGS. As shown in FIG. 1, the illumination light in which the direct light from the light source 1 and the reflected light from the reflector 2 are mixed passes through the lens 3 of the incident optical system and enters the DMD 4. DM
Video signals to be displayed on the screens of the individual projection display devices are input to D4. Light incident on the DMD 4 is reflected at a predetermined incident-reflection angle characteristic to correspond to the input video signals. The light enters the lens 5 of the projection optical system as projection light (optical image), and is enlarged and projected on the screen 10 by the lens 5 of the projection optical system. The light that has diverged and reached the back of the screen 10 first passes through the transparent reinforcing plate 130 shown in FIG.
20. The Fresnel lens sheet 120 functions equivalently to one convex lens, and converts divergent incident light into parallel outgoing light. The emitted light then enters the lenticular sheet 110. Vertically striped lenticular lens 111 formed on lenticular sheet 110
Spreads light microscopically in the horizontal direction, increasing the horizontal viewing angle.

Here, the light rays from the outermost peripheral portion of the optical image enter near the connection between the screen 10 and the housing 20.
As shown in FIG. 1, by providing a cutout portion having a step H <b> 2 on the inner peripheral side of the end of the housing 20, the light beam 51 from the outermost peripheral portion of the optical image is not blocked by the housing 20, 10 and is designed to form an image at the outermost peripheral portion of the outermost surface of the screen. Adjacent projection display devices 30 are arranged close to each other and arranged so that there is almost no gap between adjacent screens. Therefore,
In the large-screen display device according to the present embodiment, one large-screen display screen formed by synthesizing the individual screens 10 can eliminate the non-display portion caused by the gap between the individual screens 10. it can. In this embodiment, since the opaque tape 60 is used for bonding and fixing the screen 10 and the end of the housing 20, the opaque tape 60 becomes a black line when the screen is viewed from an oblique direction. There is a phenomenon that appears.

In the projection display device used in the large-screen display device according to the present embodiment, the screen 10 and the housing 20 are made of a material having substantially equal thermal expansion coefficients. Even when the temperature of the inside or the surroundings increases, the expansion rates of the screen 10 and the housing 20 are equal, and there is no possibility of distortion. Therefore, adjacent screens can be arranged in close contact with almost no gap. Therefore, when a large number of projection display devices are combined and displayed, the display screen configured as one large screen does not curve due to temperature rise, and
The area of the non-display portion generated between the individual screens is very small, and a high-quality large-screen display device can be realized. In the present embodiment, an example of a projection device using a DMD is described, but the present invention is not limited to this.
It goes without saying that any device that converts a video signal into an optical image (for example, liquid crystal) may be used.

Embodiment 2 FIG. FIG. 3 is a configuration diagram showing a horizontal cross section of a joint portion between the screen 10 and the housing 20 of the projection display device constituting the large screen display device according to the second embodiment. In the figure, reference numeral 20 denotes a housing, 110 denotes a lenticular sheet, 120 denotes a Fresnel lens sheet, and 130 denotes a transparent reinforcing plate, which are the same as those in the first embodiment shown in FIGS. It is. Reference numeral 140 denotes an acrylic resin front sheet. Screen 1
0 is front seat 140, lenticular sheet 1
10, Fresnel lens sheet 120 and reinforcing plate 130
It is composed of As in the first embodiment, the lenticular sheet 110 includes a lenticular lens 111 having a vertical stripe shape and a black stripe 11.
2 are formed.

Further, 61 is a front seat 140,
Lenticular sheet 110, Fresnel lens sheet 1
20 is a transparent tape having an adhesive property for abutting the peripheral portion of the screen 10 composed of the reinforcing plate 130 and the peripheral portion of the screen 10 to the end of the housing 20 and joining the same. It is wound around the outer periphery of the end of the body 20 and the side surface of the screen 10. The material of the transparent tape 61 is, for example, an industrial polyester tape and has a thickness of about 0.1 mm.

The behavior until the light from the light source 1 reaches the screen 10 is the same as in the first embodiment. The optical path of the light incident on the screen 10 will be described with reference to FIG. FIG. 4 is an enlarged horizontal sectional view of a part of the outer peripheral portion of the screen. The light reaching the outer peripheral portion of the screen passes through a reinforcing plate 130 (not shown) and enters the Fresnel lens sheet 120. Among them, the light ray a in FIG.
The light travels in a direction perpendicular to the screen surface by the Fresnel lens sheet 120, enters the center of the lenticular lens 111, passes through the lenticular sheet 110 and the front sheet 140 while maintaining this direction, and passes through the screen. Emitted from the surface. Therefore,
When the observer observes the screen, the light ray a is recognized as an image near the outer periphery of the screen.

In the light incident on the Fresnel lens sheet 120, the light ray b is incident on a position slightly shifted from the center of the lenticular lens 11, and travels slightly upward in the figure from a direction perpendicular to the screen surface. This ray b
Is incident on the transparent tape 61 through the end face of the front sheet 140. The refractive indices n ₁ of the front sheet 140 and the transparent tape 61 are substantially the same (n ₁ ≒ 1.
In contrast to 5), the refractive index n ₂ of the air layer on the outer peripheral surface of the transparent tape 61 is 1. Therefore, on the inner surface of the transparent tape 61, the light beam b incident at an angle θ larger than the critical angle θc is totally reflected and exits from the end face of the transparent tape 61 as shown in FIG. Note that the critical angle θc is s
in θc = n ₂ / n ₁

The light ray c of the light incident on the Fresnel lens sheet 120 is incident on the end of the lenticular lens 111 and travels upward in the figure from a direction perpendicular to the screen surface. The light beam c enters the transparent tape 61 through the end face of the front sheet 140 similarly to the light beam b, and is totally reflected on the surface of the transparent tape 61. The totally reflected light beam c is again reflected from the front sheet end face to the front sheet 1
The light enters the front sheet 40 and exits from the front sheet surface.

Next, how the observer looks at the outer peripheral portion of each screen will be described with reference to FIG.
Light rays b and c in the figure are the same as the light rays shown in FIG. 4, and are totally reflected on the surface of the transparent tape 61 and emitted from the end face of the transparent tape and the front sheet 140 surface. When the observer observes the outer peripheral portion of each screen, that is, the vicinity of the portion where the transparent tape 61 is wound, the tape thickness is very thin, so when the screens are arranged vertically, the tape position is slightly above or below the tape position. From the side, when the screens are side by side, you will see from the slightly left or right side of the tape position.

That is, the light rays b and c emitted from the screen surface shown in FIG. 5 are seen. Since the light beam b and the light beam c are totally reflected on the inner peripheral surface of the transparent tape 61, the same effect as when a plane mirror is installed at the surface position of the transparent tape 61 has the same effect. A virtual image 200 is observed on the line. Therefore, when viewing the outer peripheral portion of each screen 10, light does not reach the observer's eyes at all only when the tape end face of the transparent tape 61 is viewed from the normal direction, and it is configured as one large screen. When the entire display screen is observed, a non-display portion between the screens 10 is hardly recognized.

For comparison, instead of the transparent tape 61,
When using opaque tape (black tape),
This will be described with reference to FIG. In the figure, reference numeral 60 denotes an opaque tape (black tape) that does not transmit light. Of the light that has entered the Fresnel lens sheet 120, the light ray a enters the center of the lenticular lens, and the lenticular sheet 11
0, the light passes through the front sheet 140 and exits from the screen surface.
It reaches the end face and is absorbed by the black tape 160. Therefore, when the observer observes the outer peripheral portion of each screen, not only when the tape end face is viewed from the normal direction, but also when viewing the vicinity of the tape from a slightly upper side or a lower side (or a left side or a right side), there is no light. Are not visible and are recognized as black lines. That is, when an image is displayed on the entire screen, a black linear non-display portion occurs between the screens.

However, in the present embodiment,
An end of each screen 10 and the housing 20 is a transparent tape 61.
The light incident on the transparent tape 61 from the side of the screen is not absorbed by the transparent tape 61 but is specularly reflected on the inner peripheral surface of the transparent tape. For this reason, when the observer observes the boundary between the adjacent screens 10, the brightness near the boundary looks uniform, and the presence of a non-display part such as a black line is not recognized. A screen display device can be realized. The difference in appearance between the present invention and the conventional structure is particularly remarkable when uniform white display or the like is performed between adjacent screens.

Embodiment 3 FIG. 7 is an enlarged horizontal cross-sectional view of a part of the outer peripheral portion of the screens 10 of the projection display devices adjacent to each other (that is, the adjacent portions of the screens 10) in the large screen display device according to the third embodiment. . In the figure, 110 is a lenticular sheet, 12
Reference numeral 0 denotes a Fresnel lens sheet, and 140 denotes an acrylic resin front sheet, which are the same as those in the first embodiment shown in FIGS. Note that, similarly to the first or second embodiment, the lenticular sheet 110 is formed with a lenticular lens 111 having a vertical stripe shape and a black stripe 112. Reference numeral 62 denotes an adhesive transparent wrapped around each projection display device in order to join and fix the screen 10 and an end portion (not shown) of the housing 20 so as not to shift. This tape has an irregular surface 62a formed by embossing on the outer surface.

The light beam d is a light beam that is transmitted from the light source and incident on the Fresnel lens sheet 120, passes through the lenticular sheet 110, is incident on the front sheet 140, and reaches the end face of the front sheet 140.
The behavior of the light beam d will be described below. The light beam that has reached the end face of the front sheet 140 enters the transparent tape 62 and propagates through the tape. Then, the transparent tape 62
The light reaching the unevenness 62a is scattered in all directions by the unevenness 62a. Among them, a part of the light scattered and reflected is emitted from the end face of the tape or the surface of the front sheet 140 similarly to the light rays b and c shown in the second embodiment.

A part of the light scattered and transmitted by the irregularities 62a of the transparent tape 62 reaches the surface of the transparent tape 62 wound around the projection display devices arranged adjacent to each other and is similarly scattered. Some light that does not reach the surface of the adjacent tape passes through the gap 41 between the transparent tapes 62 and exits from the screen surface. As described above, in the present embodiment, even when a slight gap 41 exists between the screens of the adjacent projection display devices, light is emitted from the end face of the transparent tape and the gap 41 between the transparent tapes. Therefore, when the observer views the entire display screen configured as one large screen, the non-display portion between the screens 10 is hardly recognized.

Although the case where the surface of the transparent tape is embossed has been described above, for example, a tape having bead coating applied to the surface of the tape to have a diffusive property, or a design in which light is emitted from the screen surface. What formed the formed fine prism on the tape surface can also be used.

[0035]

A large-screen display device according to the present invention forms an optical image in accordance with a video signal and accommodates and holds a projection device for enlarging and projecting the optical image, and enlarges the image by the projection device. In a large screen display device in which a plurality of projection display devices each including a screen for displaying a projected optical image are arranged, each projection display device abuts a peripheral portion of the screen at an end of a housing. The screen and the screen are joined to the end of the housing and fixed, and the housing and the screen are made of a material having substantially the same thermal expansion coefficient, and a plurality of screens are provided so that adjacent screens are in close contact with each other. Since the projection type display devices are arranged, even if the temperature around the device changes, the expansion rates of the screens of the individual projection type display devices and the casing are equal, and the screens of a plurality of projection type display devices are brought into close contact with no gaps. It is composed of one large-screen display screen by reducing the area of the non-display portion generated between over emissions,
This large screen display screen does not curve. That is, according to the present invention, it is possible to realize a high-quality large-screen display device in which an unsightly non-display portion between the screens is small and the display screen is not curved even by a temperature change.

Further, the large screen display device according to the present invention
A projection-type display that forms an optical image according to a video signal and houses and holds a projection device that enlarges and projects the optical image, and a screen that displays the optical image enlarged and projected by the projection device. In a large-screen display device in which a plurality of devices are arranged, each projection display device is configured such that the peripheral portion of the screen is brought into contact with the end of the housing, and the screen is attached to the housing using a transparent tape. Since a plurality of projection display devices are arranged so that the adjacent screens are in close contact with each other via the transparent tape while being fixed to the end portion, light incident on the transparent tape from the side of the screen. Is specularly reflected on the tape surface without being absorbed by the tape. Therefore, when an observer observes the boundary between adjacent screens, a high-quality large-screen display device in which the brightness near the screen boundary looks uniform and the presence of an unsightly non-display portion between the screens is not recognized. Can be realized.

In the large-screen display device according to the present invention, the housing and the screen constituting the projection display device are characterized by being made of a material having substantially the same thermal expansion coefficient. A large-screen display screen in which the screens of a projection display device are closely adhered to each other without gaps does not bend even when the temperature changes, and when an observer observes the boundary between adjacent screens, It is possible to realize a very high-quality large-screen display device in which the brightness near the boundary looks uniform and the presence of an unsightly non-display portion between the screens is not considered.

Further, in the projection display device of the large screen display device according to the present invention, the transparent tape for joining and fixing the screen to the end of the housing is provided with irregularities on its outer surface. Therefore, part of the light incident on the transparent tape is scattered and reflected by the irregularities on the outer surface of the tape, and even if there is a slight gap between adjacent screens, some light is transmitted from the gap to the observation side surface. The light is emitted, and the non-display portion caused by the gap hardly occurs, so that a high-quality large-screen display device can be realized.

Further, in the projection type display device of the large screen display device according to the present invention, after the light from the outermost peripheral portion of the optical image emitted from the projector passes through the screen, the outermost peripheral surface of the screen becomes Since the end of the projection display device is shaped so that an image is formed at a portion, the synthesized video signal displayed on one large-screen display screen is continuous at a joint between the screens. , And a high-quality large-screen display device can be realized.

[Brief description of the drawings]

FIG. 1 is a diagram showing a cross section when two projection display devices constituting a large screen display device according to a first embodiment of the present invention are closely arranged.

FIG. 2 is a perspective view showing components of a screen of the projection display device.

FIG. 3 is a horizontal cross-sectional view showing a joint between a screen and a housing of a projection display device that constitutes a large screen display device according to a second embodiment.

FIG. 4 is a diagram for explaining an optical path of an incident light beam on a screen in a projection display device constituting a large-screen display device according to a second embodiment.

FIG. 5 is a diagram for explaining how a screen is viewed by an observer in a projection display device included in the large-screen display device according to the second embodiment.

FIG. 6 is a diagram for explaining how a screen is viewed by an observer when an opaque tape is used in the projection display device according to the second embodiment.

FIG. 7 is a diagram for explaining an optical path of an incident light beam on a screen in a projection display device included in the large screen display device according to the third embodiment.

FIG. 8 is a perspective view showing a schematic structure of a conventional large-screen display device.

FIG. 9 is a configuration diagram showing a cross section when two projection display devices constituting a conventional large-screen display device are closely arranged.

FIG. 10 is an enlarged view of a portion A in FIG. 9;

[Explanation of symbols]

REFERENCE SIGNS LIST 1 light source 2 reflector 3 lens of incident optical system 4 DMD 5 lens of projection optical system 10 screen 20 housing 30, 40 projection display device 41 gap 50 projection device 51 light beam from outermost peripheral portion of optical image 60 opaque tape 61 Transparent tape 62 Transparent tape having irregularities on its surface 62a Irregularities on embossed surface 110 Lenticular sheet 111 Lenticular lens 112 Black stripe 120 Fresnel lens sheet 130 Reinforcement plate 140 Front sheet 200 Virtual image

Continuing from the front page (72) Inventor Kohei Teramoto 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Electric Corporation F-term (reference) 2H021 AA05 BA24 5C058 AB06 AB08 BA23 EA01 EA03 EA11 EA12 EA13 EA32 EA36 EA38 5C094 AA14 AA34 DA01 FB03 FB20 HA10 5G435 AA01 AA12 BB17 DD02 DD07 EE02 GG46 HH18

Claims (5)

[Claims] 1. A housing for storing and holding a projection device for forming an optical image according to a video signal and enlarging and projecting the optical image, and a screen for displaying the optical image enlarged and projected by the projection device. A large-screen display device comprising a plurality of projection display devices, wherein each projection display device abuts a peripheral portion of a screen on an edge of a housing, and the screen is connected to an edge of the housing. The housing and the screen are made of a material having substantially the same coefficient of thermal expansion, and a plurality of projection display devices are arranged so that adjacent screens are in close contact with each other. Large screen display device. 2. A housing which forms and forms an optical image in accordance with a video signal and stores and holds a projection device for enlarging and projecting the optical image, and a screen for displaying the optical image enlarged and projected by the projection device. A large-screen display device comprising a plurality of projection-type display devices, wherein each projection-type display device abuts the peripheral portion of the screen at an end of a housing, and uses a transparent tape to form the screen using a transparent tape. A large-screen display characterized by arranging a plurality of projection display devices such that adjacent screens are in close contact with each other via the transparent tape while being fixed to an end of the housing. apparatus. 3. The large-screen display device according to claim 2, wherein the housing and the screen constituting the projection display device are made of materials having substantially equal thermal expansion coefficients. 4. The large-screen display device according to claim 2, wherein irregularities are provided on an outer surface of the transparent tape. 5. An end portion of the projection display device so that light rays from the outermost periphery of the optical image emitted from the projection device pass through the screen and form an image at the outermost periphery of the outermost surface of the screen. 5. The molding according to claim 1, wherein the molding is performed.
The large-screen display device according to any one of claims 1 to 7.