JP2751257B2 - Multi-screen display device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a multi-screen display device.

[Related Art] In a conventional multi-screen display device, a plurality of rear-projection display devices are stacked to constitute one screen.

[Problem to be Solved by the Invention] However, the conventional multi-screen type display device has a problem that a boundary formed by a wall surface of a housing for supporting a screen is visually recognized. In view of the above, an object of the present invention is to form a boundary supporting a screen with a light guide, thereby transmitting projection information also to the boundary, thereby obtaining a continuous and integrated display.

Means for Solving the Problems According to the present invention, in a multi-screen display device including a plurality of rear projection units, the rear projection unit includes a projection display device and light emitted from the projection display device. Is projected, and a light guide for transmitting an image of a boundary portion to a boundary portion of the screen is arranged in a peripheral portion of the screen.

 Hereinafter, the present invention will be described in detail with reference to examples.

Embodiment 1 FIG. 1 is a cutaway sectional view of a multi-screen display device of the present invention. One rear projection unit 103
Is composed of a rear projection display device 105 (hereinafter abbreviated as PJ) and a rear projection screen 102. Then, the unit can project a part of the whole image to form one image as a whole. Reference numeral 104 denotes a housing for the entire unit and a structure for supporting a rear projection screen (hereinafter abbreviated as a screen). On the screen side of the structure, a light guide 101 for transmitting an image of a boundary portion is installed, and supports the screen. In this embodiment, an LCD-PJ using a liquid crystal electro-optical device (hereinafter abbreviated as LCD) as disclosed in JP-A-61-99118 for an image forming apparatus, and a transparent acrylic resin as a light guide were used.

FIG. 2 is a sectional view of a unit of a multi-screen display device employing an LCD-PJ. Since this LCD-PJ201 has no glass tube and is lightweight, the design strength of the housing can be reduced, and the weight of the unit can be reduced. Also like CRT-PJ
If RGB has separate optical axes, the light guide needs to be optimally designed for these three axes. LCD-PJ is RGB
Since the optical axes of the light guides are aligned, there is an advantage that the light guide needs to be optically designed for only one axis. FIG. 3 is a sectional view of a boundary portion of the unit as viewed from above. Actually, a light guide is installed on the screen side of the four walls. Reference numeral 303 denotes a wall, on which a light guide 301 is installed, and further, a screen 302 is supported. After all, the screen is integrated into the unit.

The PJ overlaps and projects video information up to the edge of an adjacent unit. The light beam indicated by the oblique line 304 is the projection light of the boundary portion transmitted by the light guide. in this way
By adding the overlap of the boundary portion to the PJ projection signal, discontinuity between units is reduced, and a more natural image is obtained.

As shown in FIG. 3, the light guide is shaped so that the incident angle is substantially vertical so as not to refract the light beam from the PJ, and furthermore, is provided with an anti-reflection coating. In addition, the boundary 305 between adjacent units is filled with a silicon resin having a refractive index substantially equal to that of the acrylic resin, so that reflection at the interface is avoided as much as possible.

The light guide may be formed integrally with the screen. FIG. 4 is a sectional view of the integrally molded light guide screen. The basic structure and operation are the same as those of the separated type shown in FIG. In the case of FIG. 4, a light guide was formed when the convex Fresnel lens 401 installed on the PJ side of the screen was formed. A lenticular lens 402 is arranged outside the convex Fresnel lens 401.

In the case of FIG. 1, the light guide is installed on the four wall surfaces of the unit. However, it is possible to correct the projected image only on one of the upper and lower surfaces and the left and right surfaces (for example, upper and right sides). In this case, one of the adjacent units compensates for the image at the boundary.

In addition, as shown in FIG. 5, since the LCD-PJ503 can employ a projection system with an off-axis, the optical path can be folded within a limited space. A light guide 501 supports the screen 502 on one side. Reference numeral 504 denotes a return reflection mirror. At this time, the light guide has been designed for one optical axis.

Embodiment 2 Embodiment 2 uses an integrated body of plastic optical fibers as a light guide. The basic operation of transmitting the boundary projection light from the PJ to the edge of the screen is the same as in the first embodiment. Therefore, the entire configuration except for the screen and the light guide is the same.

FIG. 6 is a sectional view of a boundary portion of the unit as viewed from above. The light guide 601 is provided on the screen 602 side of the wall 603. The PJ projects the image information of the edge of the unit onto the entrance surface of the light guide, and is transmitted to the screen by the light guide. The light flux shown by the oblique line 604 is the projection light of the boundary portion transmitted by the light guide, and hits the wall body and is not projected conventionally.

If the light guide made of the fiber integrated body of this embodiment is used, the image can be transmitted one-to-one as long as the light enters the NA, and the degree of freedom in designing the light guide is increased. This is CRT-PJ
This is effective when the number of optical axes is not one as shown in FIG. In addition, there is an advantage that the resolution is less deteriorated because it is not affected by reflection and scattering in the light guide.

However, if the length of the fiber is long, there is a problem that the image forming position of the projection light changes because the optical path length of the fiber incident surface and the screen are different. Also, the strength for supporting the screen is reduced. Therefore, in this embodiment, as shown in FIG. 6, a fiber optical system having a trapezoidal cross section is used. Table 1 shows details of the present embodiment.

Also, by using a so-called tapered fiber in which the diameter of the fiber is increased at the incident portion, it is possible to compensate for a decrease in projection light in the peripheral portion. In this case, a signal corrected on the PJ side may be inserted. In other words, the compensation for the transmission loss and the decrease in the peripheral light amount is corrected by the area of the light guide light-entering portion, and at this time, the projection light is expanded in the peripheral portion.

Further, in the case of FIG. 6, the light guide is installed on the four wall surfaces of the unit, but the projected image can be corrected only on one of the upper and lower surfaces and the left and right surfaces (for example, the upper and right sides). In this case, one of the adjacent units compensates for the image at the boundary.

Further, a nested light guide structure in which adjacent units are intricate and both compensating for the image of the boundary portion may be adopted. FIG. 7 is an enlarged sectional view of the nesting state between the units. Reference numeral 702 denotes a screen boundary, and a hatched portion 701
Indicates a light guide on the right side as viewed from the front. At this time, the PJ projection signal is added with an overlap of about the boundary between the units. Due to the overlap, discontinuity between units is reduced, and there is an advantage that a natural image can be obtained.

Although the embodiments have been described above, the present invention can adopt not only the above embodiments but also various projection apparatuses, and can be applied to any display apparatus that performs multi-projection.

[Effects of the Invention] As described above, according to the present invention, it is difficult to visually recognize the boundary, and it has an effect of obtaining a continuous image, and a display with a sense of unity can be obtained.

Furthermore, the adoption of the fiber light guide has increased the degree of freedom in design, and also has the effect of reducing the reduction in resolution.

In addition, since the weight can be reduced by adopting the LCD-PJ, a large number of units can be combined in terms of structural strength, and a large-scale display device can be easily manufactured. Further, the possibility of cost reduction and plasticization of the structure supporting this is increased, and the total cost can be reduced.

Further, since the degree of freedom of the optical system is increased, the space can be saved, particularly the depth can be reduced, and a thin device can be realized.

[Brief description of the drawings]

FIG. 1 is a cutaway sectional view of a multi-screen display device of the present invention. FIG. 2 is a sectional view of one unit viewed from above. FIG. 3 is an enlarged view of a boundary portion of the unit. FIG. 4 is a sectional view of the integrally molded light guide screen. FIG. 5 is a sectional view of a unit employing a non-optical axis projection system. FIG. 6 is a sectional view of a unit using the fiber light guide as viewed from above. FIG. 7 is an enlarged sectional view of the nesting state between the units. 101, 301, 601 Light guides 102, 302, 502, 602 Rear projection screen 103 Rear projection unit 104 Structure 105 Rear projection display 201, 503 LCD-PJ 303, 603 Wall

Claims (4)

(57) [Claims] 1. A multi-screen display device having a plurality of rear projection units, wherein the rear projection unit includes a projection display device and a screen on which light emitted from the projection display device is projected. A multi-screen display device, wherein a light guide for transmitting an image of a boundary portion to a boundary portion of the screen is arranged in a peripheral portion of the screen. 2. The multi-screen display device according to claim 1, wherein the projection type display device projects image information up to the edge of the adjacent rear projection unit. 3. The multi-screen display device according to claim 1, wherein the light guide is provided with an anti-reflection coating. 4. A multi-screen display device according to claim 1, wherein said light guide is an integrated optical fiber.