JP2008225300A - Image display device and image screen device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable an observer to easily view an image which should be displayed by an image display device on a front side of a transparent wall. <P>SOLUTION: The image display device has a dispersion plate 10 which is incorporated in a portion of the transparent wall 101 of a water tank 100 and can disperse light arriving from the reverse side of the transparent wall 101 to the top side of the transparent wall 101, and a projector 20 which projects, as the arriving light, projection light from the reverse side of the transparent wall 101 so that the light is imaged on the dispersion plate 10. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a technical field of an image display device and an image screen device capable of displaying an image on a wall surface of a water tank or a show window, for example.

  Regarding an example of this type of video display device or video screen device, a technology that can project a video on a transparent wall of a water tank while enabling observation of a landscape inside the water tank that is a structure, for example, from the outside of the water tank is a patent document. 1 is disclosed. More specifically, the projection light is irradiated from a projector disposed on the back side of the transparent wall (for example, the inside of the aquarium), passes through the transparent wall, and is on the front side opposite to the back side of the wall (for example, the aquarium) To the outside). Thereby, the observer located on the front side of the transparent wall can visually recognize the image by the emitted projection light.

JP 2001-290217 A

  However, in the state where the processing for controlling the optical function is not performed on the transparent wall, the following problems occur. That is, on the front side of the transparent wall, when the observer observes from the predetermined position with respect to the position of the projector on the back side, the image that should be originally displayed can be visually recognized with the projection light of the projector. Observing from a position out of position may result in an image that is different from the image that should be originally displayed, more specifically, an image that does not satisfy the desired level of contrast, making it difficult to view or display. A situation occurs in which the video to be displayed cannot be seen at all.

  The present invention has been made in view of the above-described problems. For example, a video display device and a video screen device that allow an observer to easily view a video to be displayed on the front side of a transparent wall are provided. The issue is to provide.

  In order to solve the above problems, a first video display device according to the present invention is built in a part of a transparent wall of a structure, and directs light coming from the back side of the transparent wall toward the front side of the transparent wall. And a projection means for irradiating projection light as the incoming light so as to form an image on the scattering plate from the back side.

  In the first image display device of the present invention, a scattering plate is formed integrally with the transparent wall as a part of the transparent wall of the structure, or the scattering plate is attached to a part of the transparent wall. Arranged. Here, the “transparent wall” according to the present invention means a transparent glass wall, a transparent acrylic wall, a glass wall of a building, a window glass or a show window glass for an aquarium or ornamental water tank as a structure. And if it can see the back side from the front side of a transparent wall, it means that it is transparent, and it is not required that it is completely transparent or the transmittance | permeability is almost 100%. Even so-called translucent is included in the transparency here as long as the back side can be seen.

  Projection means such as a projector is arranged behind the transparent wall so that the projection light forms an image on the scattering plate. Therefore, the projection light irradiated from the projection means arrives and enters the scattering plate from the back side of the transparent wall. The incident light incident on the scattering plate is scattered on the surface on the back side of the scattering plate located on the back side of the transparent wall, or on the surface on the front side of the scattering plate located on the front side of the transparent wall in addition to or instead of this. The The scattered projection light is emitted from the scattering plate toward the front side of the transparent wall.

  Here, when the scattering plate is not arranged with respect to a part of the transparent wall, even if the projection light is irradiated to the part of the transparent wall by the projection means, the projection light is in contact with the transparent wall. The light is refracted according to the difference in refractive index from the light medium, and is transmitted through the transparent wall. In this case, if the observer does not stand on the back side of the transparent wall according to the traveling direction of the light from the irradiation position of the projection light toward the transparent wall, the observer easily visually recognizes the image to be displayed by the projection light. I can't do that. That is, if the observer observes from a position other than the fixed position according to the position of the projection means that is the irradiation position of the projection light, it is difficult to visually recognize the video to be displayed.

  On the other hand, in the present invention, by projecting the projection light by the scattering plate, the traveling direction of the projection light toward the transparent wall from the irradiation position on the back side of the transparent wall is directed from the scattering plate to the front side of the transparent wall. It becomes possible to change to advance in all directions. Therefore, with respect to a part of the transparent wall where the scattering plate is located, on the front side of this part, the image can be easily visually recognized by the scattered projection light regardless of the position of the observer.

  In one aspect of the first image display device of the present invention, the scattering plate includes a transparent or translucent portion and a scattering portion that scatters the incoming light.

  According to this aspect, in the scattering plate, the transparent or translucent portion and the scattering portion are mixed on at least one of the back side and the front side of the scattering plate. The transparent or translucent portion does not need to be completely transparent or have a transmittance of almost 100%, like the above-mentioned “transparent wall”, and may be transparent or translucent.

  Here, the light coming from the back side of the transparent wall includes not only the projection light irradiated by the projection means but also the light that makes it possible to visually recognize the scenery behind the transparent wall, for example, the scenery in the aquarium or the show window on the front side. included. The light that makes it possible to visually recognize the scenery on the back side of the transparent wall is originally external light (for example, natural light) incident from the front side of the transparent wall, in addition to or in place of illumination other than the projection means from the back side of the transparent wall. Light scattered in all directions by each object in the landscape behind the transparent wall (for example, decorations in the show window and animals and plants in the aquarium) and emitted from the back side of the transparent wall toward the front side . Therefore, unlike the projection light, even if the light is transmitted through the transparent wall, the observer can easily observe the scenery behind the transparent wall on the front side.

  In this aspect, light incident on the transparent or translucent portion of the light arriving from the back side of the transparent wall is transmitted through the transparent or translucent portion and emitted toward the front side of the transparent wall. On the other hand, among the light coming from the back side of the transparent wall, the light incident on the scattering portion is scattered and emitted toward the front side of the transparent wall.

  Therefore, in this aspect, in a part of the transparent wall on which the scattering plate is arranged, in the transparent or translucent part, while ensuring a large transmittance of light coming from the back side, the projection light coming from the back side in the scattering part Can be scattered and emitted to the front side. Therefore, the observer on the front side of the transparent wall can easily view the image together with the scenery behind the transparent wall, for example, the scenery in the water tank or the show window, regardless of the observation position.

  In the aspect in which the scattering plate includes the transparent or translucent portion and the scattering portion, the scattering portion has at least one of a stripe shape, a check shape, a block shape, an island shape, and a circular shape, and the transparent or semi-transparent shape. You may comprise so that it may be scattered in a transparent part.

  If comprised in this way, it will become possible to emit scattered light corresponding to the arrangement | positioning shape of a scattering part.

  More specifically, for example, when scattering portions are scattered in a transparent or semi-transparent portion in a stripe shape, the scattering portions are arranged in a vertical stripe shape, a horizontal stripe shape, or an oblique stripe shape in the transparent or semi-transparent portion. Therefore, the light scattered in each scattering portion is emitted along each scattering portion extending in the vertical direction, the horizontal direction, or the oblique direction in the transparent or translucent portion. Therefore, it is possible to emit the projection light as a bundle of light traveling along the vertical direction, the horizontal direction, or the oblique direction from each scattering portion.

  Further, when the scattering portions are scattered in the transparent or translucent portion in a check state, the scattering portions are alternately arranged with the transparent or translucent portions, for example, along the vertical and horizontal directions. In this case, the projection light scattered at each scattering portion is emitted along the vertical direction and the horizontal direction, and proceeds toward the front side of the transparent wall.

  Alternatively, when the scattering portions are scattered in the transparent or semi-transparent portion in the form of blocks, islands, and circles, the scattering portions and the transparent or semi-transparent portions are alternately arranged in the vertical direction and the horizontal direction, or the vertical direction The scattering portions are scattered in the lateral direction and the oblique direction. Therefore, the projection light is scattered from each scattering portion and proceeds to the front side of the transparent wall. In this case, it is not emitted as a bundle of light along any one of the vertical direction, the horizontal direction, and the oblique direction, but the light scattered in each scattering portion enters each other and is emitted to the front side of the transparent wall. . Therefore, a finer and clearer image can be visually recognized by the scattered light.

  In another aspect of the first image display device of the present invention, the scattering plate has an uneven surface.

  According to this aspect, at least one surface of the back side and the front side of the scattering plate has an uneven shape. On the uneven surface, the light incident on the scattering plate is scattered in at least one of the concave and convex portions due to a difference between the refractive index and the refractive index of the medium that propagates light in contact therewith, such as air or water. It becomes possible to do.

  In an aspect in which the scattering plate has an uneven surface, at least one of the concave portion and the convex portion may be configured to have a predetermined type of optical shape on the uneven surface.

  According to this structure, at least one of the concave portion and the convex portion is formed into a predetermined type of optical shape such as a prism shape or a lens curved surface, so that the concave portion and the convex portion are formed. Light scattering can be controlled for each part. Therefore, it is possible to prevent the loss of the projection light emitted to the front side from increasing with respect to the projection light coming from the back side due to light scattering in the scattering plate.

  In another aspect of the first image display device of the present invention, the projection means irradiates the projection light obliquely from the back side, and the scattering plate has an optical path of the projection light along a normal line of the scattering plate. It is configured to scatter toward the front side while bending toward the side approaching the direction.

  According to this aspect, the projection light is projected obliquely from the back side of the scattering plate by the projection means. In this case, of the projection light that arrives on the surface of the scattering plate, the proportion of light that enters at a relatively large incident angle, that is, an angle that is greater than the critical angle with respect to the normal direction of the scattering plate, increases. Therefore, the ratio of the light incident on the scattering plate is reduced by being reflected on the surface of the scattering plate in the incoming projection light, that is, the loss of light due to reflection may be increased.

  In this aspect, on the back side of the scattering plate, the incident light irradiated from the projection means is changed, the light path of the light traveling in the direction incident at a relatively large incident angle with respect to the surface of the scattering plate is changed and scattered. It is possible to make the light incident on the scattering plate at a relatively small incident angle, that is, at an angle smaller than the critical angle with respect to the normal direction of the scattering plate.

  Therefore, it is possible to reduce the loss of light due to reflection with respect to the projection light arriving at the scattering plate, enter the scattering plate, and scatter the light so that the projection light can travel to the front side of the scattering plate.

  Therefore, in this aspect, the degree of freedom of the arrangement position of the projection unit can be set to be large corresponding to the configuration of the structure. That is, for example, on the back side (in the aquarium) of the transparent wall of the aquarium that is a structure, avoid the eyes of the observer who observes the water that is the light medium in the aquarium and the scenery in the aquarium. Even if the projector is arranged and the projection light is irradiated from the oblique direction toward the transparent wall, the observer can easily view the image by the projection light. Alternatively, for example, on the back side of the show window (inside the show window), which is an example of a transparent wall of the structure, avoiding the line of sight of the observer observing the scenery in the show window, for example, a projector is arranged as a projecting means, and transparent Even if the projection light is irradiated from the oblique direction toward the wall, the observer can easily visually recognize the image by the projection light.

  In order to solve the above-described problem, the second image display device of the present invention projects a scattering plate that can scatter light coming from the back side toward the front side, and forms an image on the scattering plate obliquely from the back side. Projection means for irradiating light as the incoming light, and the scattering plate is configured to scatter toward the front side while bending the optical path of the projection light toward the side closer to the normal direction of the scattering plate Has been.

  The second image display device of the present invention reduces the loss of light due to reflection and makes it incident on the scattering plate for the projection light arriving at the scattering plate, similarly to the other aspects of the first image display device described above. It becomes possible to advance to the front side of the scattering plate by scattering. Therefore, in the second video display device of the present invention, the degree of freedom of the arrangement position of the projection means can be set large corresponding to the structure of the structure.

  In one aspect of the first or second image display device of the present invention, the scattering plate includes a first portion that defines a light passage space that is open in a direction in which the projection light arrives, and the light. And a second portion that scatters the projection light coming through the passage space toward the front side.

  According to this aspect, the first portion is formed by, for example, the prism or the mirror on the back side of the scattering plate. The projection light arrives in the light passage space defined by the first portion. Then, in the light passage space, the light path is changed so that the projection light is refracted or reflected by the first portion and is incident on the scattering plate at a relatively small incident angle.

  Thereafter, the projection light whose optical path has been changed by the first part is incident on the scattering plate and arrives at the second part. Then, the incoming projection light is scattered by the second portion and travels to the front side of the scattering plate.

  Therefore, in this aspect, the light loss of the incoming projection light is reduced and the proportion of the light emitted to the front side is increased by a relatively simple configuration using the two optical elements of the first and second portions. It becomes possible.

  In an aspect in which the scattering plate has a first part and a second part, the first part has a light reflecting film that borders the periphery of the light passage space, and the second part has the light reflecting film. You may comprise so that the said unevenness | corrugated surface which scatters the said projection light which comes in by being reflected by the above may be scattered toward the said front side.

  If comprised in this way, it will become possible to form the 1st part with a mirror, reflect the projection light which arrived in the space for light passage on the surface, and to change the optical path.

  Further, in the second portion, a refractive index difference is generated between the uneven surface and a light medium filled in a light passage space in contact with the uneven surface, for example, air or water. On the other hand, it becomes possible to scatter the projection light coming through the light passage space.

  Therefore, in the first part, the change of the optical path by the first part is controlled by adjusting the inclination angle made with respect to the normal direction of the scattering plate on the surface, and in addition to or instead of this, the concave part In addition, by forming at least one of the convex portions into a predetermined type of optical shape such as a prism or a lens, it is possible to control light scattering for each concave portion and convex portion.

  Therefore, in this aspect, the loss of the projection light emitted to the front side of the projection light arriving from the back side of the scattering plate is prevented from increasing due to the reflection and scattering in the first and second portions. Can do.

  Alternatively, in an aspect in which the scattering plate has a first portion and a second portion, the first portion has a light guide material filled in the light passage space, and the second portion has the light guide material. It may be configured to have an uneven surface that scatters the projection light that arrives by being guided in the direction toward the front side.

  If comprised in this way, it will become possible to prevent the situation where the loss of light becomes large because the projection light which arrives in the space for light passage advances again from this space toward the back side of the scattering plate. . That is, after the optical path of the projection light arriving in the light passage space is changed by the first portion, the light is guided so as to be incident on the second portion by the light guide material filled in the space. Can do.

  Furthermore, in the aspect in which the scattering plate has the first portion and the second portion, the projection means irradiates the projection light from obliquely above, and the first portion extends in the horizontal direction as the light passage space. A stripe-shaped gap may be defined.

  If comprised in this way, it will become possible to prevent that the loss of light becomes large because the projection light irradiated from a projection means is interrupted | blocked by the 1st part. That is, in this aspect, the first portion defines a light passage space in the scattering plate in common with the second portion arranged in the horizontal direction. That is, in the scattering plate, the first portion is provided as a blind so as to define a gap with respect to the second portion, so that it is difficult for the projection light to pass through the shadow portion of the first portion.

  In this aspect, the arrangement area of the first part is minimized on the back side of the scattering plate, and the first part is used to open the light passage space upward, which is the irradiation direction of the projection light from the projection means. Can be defined as

  In order to solve the above-described problem, a first video screen device of the present invention is a video screen device that projects an image when irradiated with projection light, and is built in a part of a transparent wall of a structure. And a scattering plate capable of scattering light coming from the back side of the transparent wall toward the front side of the transparent wall.

  The first video screen device of the present invention is similar to the first video display device of the present invention described above, and a part of the transparent wall on which the scattering plate is located is located at the viewer's position on the front side of this part. Regardless, the video can be easily viewed.

  In order to solve the above-mentioned problem, the second video screen device of the present invention is a video screen device in which an image is projected by irradiation with projection light, and can scatter light coming from the back side toward the front side. The scattering plate is configured to scatter toward the front side while bending the optical path of the projection light coming obliquely from the back side to the side approaching the normal direction of the scattering plate. Yes.

  The second video screen device of the present invention, like the above-described second video display device of the present invention, reduces the light loss due to reflection with respect to the projection light arriving at the scattering plate and makes it incident on the scattering plate. It becomes possible to advance to the front side of the scattering plate by scattering. Therefore, the degree of freedom of the arrangement position of the projection means can be set to be large corresponding to the structure of the structure.

  The operation and other advantages of the present invention will become apparent from the best mode for carrying out the invention described below.

  Hereinafter, embodiments of the video display device and the video screen device of the present invention will be described with reference to the drawings.

<First Embodiment>
A first embodiment of the present invention will be described with reference to FIGS. In the present embodiment, the video screen device is included in the video display device. First, the configuration of the video display device in the present embodiment will be schematically described with reference to FIG. FIG. 1 is a diagram showing a schematic overall configuration of a video display apparatus according to the present embodiment.

  FIG. 1 shows a configuration of a video display device when video is displayed on a transparent wall such as a transparent glass wall or transparent acrylic wall of an aquarium or ornamental water tank as a structure. In this example, the description of the fish in the aquarium is projected on the transparent wall as an image, as in “This fish is OO”. In addition, as a typical example, in addition to such a case, it is also possible to display an image on a glass wall of a building, a window glass, a show window glass, or the like by using an image display device.

  In FIG. 1, the video display device includes a scattering plate 10 formed as a part of the transparent wall 101 of the water tank 100, in other words, formed integrally with the transparent wall 101. Alternatively, the scattering plate 10 is attached to a part of the transparent wall 101 of the water tank 100.

  The transparent wall 101 is formed to be transparent or translucent, and an observer A on the front side, which is the opposite side to the back side of the transparent wall 101 on which the projector 20 which is an example of the “projection unit” according to the present invention is arranged, is provided. A landscape in the water tank 100 from the front side to the back side, for example, water filled in the water tank 100, animals and plants in the water, etc. can be observed.

  More specifically, the transparent wall 101 is formed so that illumination provided outside the projector 20 on the back side of the transparent wall 101 and external light such as natural light incident from the front side of the transparent wall 101 can be transmitted. . And the illumination and external light irradiated from the back side of the transparent wall 101 are scattered or reflected in all directions by the animals and plants in the water tank 100, and are emitted toward the front side from the back side of the transparent wall 101. The transparent wall 101 is formed so as to be able to transmit the light scattered or reflected in this way, and on the front side of the transparent wall 101, the viewer A uses the scattered light transmitted through the transparent wall 101 and emitted from the water tank. The scenery in 100 can be visually recognized.

  The projector 20 is disposed in the aquarium 100 on the back side of the transparent wall 101, for example, on the water avoiding the line of sight of the observer A who observes the water including the fish in the aquarium 100 and the scenery in the aquarium 100. . In this case, as indicated by a broken line in FIG. 1, the projector 20 irradiates the transparent wall 101 with projection light from an obliquely upper side on the back side. In FIG. 1, the broken line schematically shows the state of irradiation of the projection light by the projector 20. Further, the projector 20 may be intentionally disposed in the field of view of the viewer A depending on the effect of displaying the image, or may be disposed in water, and irradiates the transparent wall 101 with projection light obliquely from below. You may do it. Furthermore, when the structure includes the aquarium 100, for example, configured as an aquarium exhibition room, the projector 20 may be disposed outside the aquarium 100 and irradiate the transparent wall 101 with projection light.

  Next, a specific configuration of the scattering plate 10 will be described with reference to FIGS. 2 (a) and 2 (b). FIG. 2A is a plan view schematically showing a configuration of the scattering plate, and FIG. 2B schematically shows a configuration of a cross-sectional portion taken along line X0-X0 ′ in FIG. It is sectional drawing.

  The scattering plate 10 includes a transparent or translucent portion 12 and a scattering portion 14 in a mixed manner on at least one of the front side located on the front side of the transparent wall 101 and the back side located on the back side of the transparent wall 101. FIG. 2B shows a configuration in which the transparent or translucent portion 12 and the scattering portion 14 are formed on the back side of the scattering plate 10.

  In FIG. 2A, the scattering portions 14 are scattered in, for example, a stripe shape and a horizontal stripe shape along the horizontal direction (lateral direction) in the transparent or translucent portion 12. Accordingly, in the direction along the vertical direction (longitudinal direction) intersecting the horizontal direction along the X0-X0 ′ line in the drawing, the transparent or translucent portions 12 and the scattering portions 14 are alternately arranged and adjacent scattering is performed. The portions 14 are arranged with an interval d0 having a value of 5 mm or less, for example. By adjusting the value of the distance d0 in this way, even when the scattering plate 10 is arranged in the field of view of the observer A, the presence of the scattering plate 10 is not hindered by the function of the scattering plate 10 described below. The observer A can also observe the display image by the projection light of the projector 20 while observing the scenery in the water tank 100 easily.

  Note that the presence of the scattering plate 10 obstructs the view of the observer A for observing the scenery in the water tank 101, and if it is difficult to observe the scenery in the water tank 101, the observation is made on the transparent wall 101. The scattering plate 10 may be arranged at a position that avoids the field of view for the person A to observe the scenery in the water tank 101. Thereby, in the transparent wall 101, the area | region which can display an image | video with respect to the scattering plate 10 other than the area | region where the observer A can observe the scenery in the water tank 101 is arrange | positioned.

  Further, as shown in FIG. 2B, in the scattering plate 10, the scattering portion 14 is formed as a convex portion whose surface located on the back side of the scattering plate 10 protrudes in a convex shape, for example. Accordingly, the surface of the transparent or translucent portion 12 is formed to be substantially flat, and the scattering portion 14 is formed as a convex portion, whereby the scattering plate 10 has an uneven surface on the back side. Here, the scattering portion, that is, the convex portion 14 is formed so that the surface located on the back side of the scattering plate 10 has, for example, a predetermined type of optical shape, for example, a lens curved surface or a prism shape. The term “lens curved surface” as used herein means that the surface shape of the convex portion 14 is formed in the shape of the lens curved surface of a convex lens or a concave lens, and the “prism shape” refers to the surface shape of the prism. It means that a surface shape is formed. Therefore, in the convex part 14, the light which comes from the back side of the scattering plate 10 can be scattered by the refractive index difference with the light medium which contacts this (for example, water in the water tank 100 shown in FIG. 1).

  Next, video display performed by the video display device will be described with reference to FIGS. 3 and 4 in addition to FIGS. 1 and 2. FIG. 3A is a cross-sectional view showing the light arriving at the scattering plate in the cross-sectional portion shown in FIG. 2B, and FIG. 3B is a comparative example in which the scattering plate is arranged. It is sectional drawing which shows the appearance of the light which arrives in a part of power transparent wall. FIG. 4 is a perspective view showing the appearance of light arriving at the scattering plate.

  In FIG. 1, the projector 20 is disposed on the back side of the transparent wall 101 so that the projection light forms an image on the scattering plate 10. Therefore, as schematically shown by a broken line in FIG. 1, the projection light emitted from the projector 20 arrives and enters the scattering plate 10 from the back side of the transparent wall 101. As shown in FIG. 1, the light arriving at the scattering plate 10 from the back side is propagated by, for example, water in the water tank 100 or a medium such as air in addition to the water, and arrives at the scattering plate 10 in the transparent wall 101.

  In FIG. 3A, an example of the traveling direction of the light incident on the scattering portion 14 from the back side of the scattering plate 10 is indicated by an arrow P4, and the light incident on the transparent or translucent portion 12 from the back side of the scattering plate 10 is shown. An example of the direction of travel is indicated by arrow P2.

  As described above, the scattering portion 14 is formed as a convex portion, and incident light can be scattered by a difference in refractive index from, for example, water, which is a medium in contact with the scattering portion 14. Therefore, the projection light incident on the scattering portion 14 in accordance with the traveling direction indicated by the arrow P4 is scattered by the scattering portion 14 and emitted toward the front side. Here, since the convex portion 14 has a predetermined type of optical shape, it is possible to control light scattering for each convex portion 14. More specifically, by forming the surface of the convex portion 14 into a lens curved surface or a prism shape, the proportion of the light that travels again toward the back side of the scattering plate 10 among the projection light scattered by the convex portion 14 is determined. It is possible to control so that the ratio of light emitted to the front side is increased and the ratio is increased. Therefore, it is possible to prevent the loss of the projection light emitted to the front side from increasing due to the light scattering in the scattering plate 10 with respect to the projection light coming from the back side.

  Here, as described with reference to FIG. 2A, in the configuration in which the scattering portions 14 are scattered in a horizontal stripe shape, as shown in FIG. 4, for example, according to the traveling direction indicated by the arrow P4in, The projected light that is incident and scattered from the back side into the scattering portion 14 may be emitted as a bundle of light that generally travels along the extending direction of the scattering portion 14, that is, the horizontal direction, as indicated by an arrow P 4 out in FIG. It becomes possible.

  On the other hand, in the scattering plate 10, of the light arriving from the back side of the transparent wall 101, the light incident on the transparent or translucent portion 12 according to the traveling direction indicated by the arrow P2 in FIG. The light passes through the transparent portion 12 and is emitted toward the front side.

  Next, only differences from the present embodiment will be described with reference to FIG. As for the comparative example, it is assumed that the scattering plate 10 is not disposed on a part of the transparent wall 101 and other predetermined types of optical processing are not performed. In this case, in a part 10 of the transparent wall 101 that is located at a place where an image should be displayed by the projection light of the projector 20, for example, light coming from the back side of the transparent wall 101 follows the traveling direction indicated by the arrow P <b> 2. Transmitted and emitted to the front side.

  Therefore, on the front side of the transparent wall 101, the observer A stands on the back side of the transparent wall 101 at a position A1 that follows the light traveling direction indicated by the arrow P2 from the irradiation position of the projection light toward the transparent wall 101, for example. Otherwise, the video to be displayed by the projection light cannot be easily viewed. Therefore, when the observer A observes from the positions A2 and A3 other than the fixed position A1 according to the position of the projector 20 that is the irradiation position of the projection light, it is difficult to visually recognize the image to be displayed.

  On the other hand, in the present embodiment, the scattering direction of the projection light indicated by the arrow P4 in FIG. It becomes possible to change so that it may progress in all directions toward the front side of the transparent wall 101. Therefore, the observer A can easily visually recognize the video to be displayed even when observing from the positions A2 and A3 other than the fixed position A1 according to the position of the projector 20 that is the irradiation position of the projection light.

  Moreover, in this embodiment, as demonstrated with reference to Fig.3 (a), in the scattering plate 10, in the transparent or translucent part 12, securing the transmittance | permeability of the light which comes from the back side is large, and from the back side. Incoming projection light can be scattered and emitted to the front side. Here, with respect to the light coming from the back side of the transparent wall 101 with respect to the scattering plate 10, in addition to the projection light from the projector 20, the scenery on the back side 101 of the transparent wall, for example, the scenery in the aquarium 100 is visually recognized on the front side. Also included is the light that enables it. As already described, since such light is scattered in the water tank 100, even if it is transmitted through the scattering plate 10, the viewer A can easily observe the scenery behind the transparent wall 101 on the front side. Can do.

  Therefore, in the present embodiment as described above, the observer A on the front side of the transparent wall 101 can easily project with the scenery on the back side of the transparent wall 101, for example, the scenery in the water tank 100, regardless of the observation position. It is possible to visually recognize a video image.

  Next, a modified example of the present embodiment described above will be described with reference to FIGS. FIG. 5 is a cross-sectional view schematically showing a configuration of a cross-sectional portion of one configuration of the scattering plate in the present modification. FIGS. 6A and 6B are plan views schematically showing another configuration of the scattering plate in the present modification. Further, FIGS. 7A to 7D are plan views schematically showing other configurations of the scattering plate in the present modification.

  As shown in FIG. 5, in the scattering plate 10, the scattering portion 14 may be formed, for example, as a concave portion in which the surface located on the back side of the scattering plate 10 is recessed in a concave shape, for example. Alternatively, some of the plurality of scattering portions 14 arranged on the scattering plate 10 may be formed as convex portions and the other portions may be formed as concave portions. Even in this case, light scattering can be controlled for each concave or convex portion.

  Further, the scattering portions 14 may be scattered, for example, in the form of stripes in the transparent or translucent portion 12 in the form of vertical stripes along the vertical direction as shown in FIG. 6A, or as shown in FIG. Thus, it may be scattered in the form of diagonal stripes along the diagonal direction. Also in this case, similarly to the case described with reference to FIG. 4, it is possible to emit the projection light as a bundle of light traveling along the vertical direction or the oblique direction from the scattering portion 14.

  Alternatively, as shown in FIG. 7A, the scattering portions 14 may be scattered in a transparent or translucent portion 12 in a check shape, for example. In this case, for example, the scattering portions 14 are alternately arranged with the transparent or translucent portions 12 along the vertical and horizontal directions. In this case, the projection light scattered by each scattering portion 14 is emitted along the vertical direction and the horizontal direction, and proceeds toward the front side of the transparent wall 101.

  Alternatively, the scattering portion 14 in the transparent or translucent portion 12 is, for example, a block shape as shown in FIG. 7B, an island shape as shown in FIG. 7C, and as shown in FIG. For example, it may be scattered in a circle. In this case, the scattering portions 14 and the transparent or translucent portions 12 are alternately arranged in the vertical direction and the horizontal direction, or the scattering portions 14 are scattered in the vertical direction, the horizontal direction, and the oblique direction. Therefore, the projection light is scattered from each scattering portion 14 and travels to the front side of the transparent wall 101. In this case, instead of being emitted as a bundle of light along any one of the vertical direction, the horizontal direction, and the oblique direction, the light scattered by each scattering portion 14 enters and mixes and is emitted to the front side of the transparent wall 101. Is done. Therefore, a finer and clearer image can be visually recognized by the scattered light.

Second Embodiment
Next, a second embodiment of the present invention will be described with reference to FIG. The second embodiment is different from the first embodiment in that the scattering portion of the scattering plate is formed so as not to be mixed with the transparent or translucent portion. Therefore, only the points different from the first embodiment will be described below with reference to FIG. 8, and the same configuration as the first embodiment will be described with reference to FIGS. Sometimes omitted.

  Fig.8 (a) is a top view shown about arrangement | positioning of the scattering part of the scattering plate in 2nd Embodiment, FIG.8 (b) is schematic about the structure of the cross-sectional part of a scattering plate about 2nd Embodiment. FIG.

  As shown in FIG. 8A, in the second embodiment, in the scattering plate 10, at least part of the scattering portion 14 is formed without being mixed with the transparent or translucent portion. As shown in FIG. 8A or FIG. 8B, for example, each scattering portion 14 is formed as a convex portion on the back side of the scattering plate 10, and the surface of the convex portion 14 is, for example, on the back side of the scattering plate 10. It forms so that it may contact with the adjacent convex part 14, or it may intersect. For example, when the surface of the convex portion 14 has a lens curved surface as a predetermined type of optical shape, the lens curved surface of the convex portion 14 is in contact with the lens curved surface of the adjacent convex portion 14 on the back side of the scattering plate 10. Or formed to intersect. In addition, in FIG. 8A, in the case where the curved surface has a lens curved surface by the circular lines in the convex portion 14, each of the positions arranged at the same height in the curved surface of the lens is shown as a contour line. Thus, an example of the shape of the lens curved surface is schematically shown.

  The projection light irradiated by the projector 20 is incident on each scattering portion 14 from the back side of the scattering plate 10 in accordance with the traveling direction indicated by, for example, the arrow P4 in FIG. 8B, and is scattered and emitted toward the front side. Is done. Here, as described above, the lens curved surfaces of the adjacent scattering portions 14 are formed so as to contact or intersect with each other, so that the surface on which the scattering portions 14 are arranged on the back side of the scattering plate 10 is uniformly formed. It becomes possible to scatter light arriving at the surface toward the front side.

  Accordingly, also in the second embodiment, as in the first embodiment, the viewer A can more easily visually recognize the image to be displayed by the projector 20 regardless of the position on the front side of the transparent wall 101 shown in FIG. It becomes possible.

<Third Embodiment>
Next, a third embodiment of the present invention will be described with reference to FIGS. The third embodiment is different from the first or second embodiment in that in the scattering plate, a space for passing light of incoming light is defined with respect to the scattering portion. Therefore, hereinafter, only differences from the first or second embodiment will be described with reference to FIGS. 9 and 10, and configurations similar to those of the first or second embodiment will be described with reference to FIGS. The description will be made with reference to FIG.

  FIG. 9 is a diagram showing the positional relationship between the light passage space on the scattering plate and the projector. FIG. 10A is a cross-sectional view schematically showing the configuration of the cross-sectional portion of the scattering plate in the third embodiment, and FIG. 10B shows the light arriving at the scattering plate of the third embodiment. It is sectional drawing which shows the appearance.

  9 and 10A, the scattering plate 10 has a first portion 14a and a second portion 14b. The second portion 14b corresponds to the scattering portion shown in FIG. 1 to FIG. 4 or FIG. 8, and is formed so that incoming light can be scattered by convex portions and concave portions formed on the front side or the back side of the scattering plate 10. Is done. 10 (a) or 10 (b) shows the configuration of the second portion 14b formed as a recess on the back side of the scattering plate 10.

  Here, for example, in FIG. 9, as described with reference to FIG. 1, the projector 20 in the water tank 100 is diagonally above the back side of the transparent wall 101 as indicated by the broken line in FIG. 9. To the position where the projection light is irradiated. In FIG. 9, as in FIG. 1, the broken line schematically shows how the projection light is irradiated by the projector 20.

  The first portion 14a is provided as a blind so as to define a light passage space with respect to the second portion 14b. More specifically, the first portion 14a preferably defines a space for light passage in the scattering plate 10 as a gap 14h common to the second portion 14b arranged in the horizontal direction. Therefore, the gaps 14h are arranged in stripes on the scattering plate 10.

  Moreover, as shown in FIG. 9, the projection light irradiated from diagonally upward on the back side of the scattering plate 10 travels toward the first portion 14a, for example, according to the traveling direction indicated by the arrow P4 in FIG. In this case, the first portion 14a preferably defines a light passage space obliquely upward where light arrives. Accordingly, the gap 14h is provided as a space that opens toward the light traveling direction indicated by the arrow P4.

  10A and 10B, the projection light emitted from the projector 20 travels according to, for example, the arrow P4 and arrives at the gap 14h. The projection light that has arrived at the gap 14h is refracted or reflected by the first portion 14a and arrives at the second portion 14b.

  Here, in FIG. 10B, the first portion 14a is formed as a mirror having a light reflecting film 14aa formed of a metal material such as aluminum (Al) so as to border the gap 14h. Therefore, the light arriving at the gap 14h is incident on and reflected by the light reflecting film 14aa of the first portion 14a, and its optical path is changed.

  Projection light that is irradiated obliquely from the projector 20 and arrives at the scattering plate 10 has a relatively large incident angle, that is, a ratio of light incident at an angle greater than a critical angle with respect to the normal direction of the scattering plate 10. There is a tendency to grow. Therefore, the ratio of the light incident on the scattering plate 10 is reduced by being reflected on the surface of the scattering plate 10 in the incoming projection light, that is, the loss of light due to reflection may be increased.

  In the third embodiment, as shown in FIG. 10B, the direction of the incident light incident on the surface of the scattering plate 10 at a relatively large incident angle by changing the optical path of the projection light that has arrived by the first portion 14a. Even the light traveling in the direction toward the second portion 14b has a relatively small incident angle with respect to the surface of the second portion 14b, that is, the normal direction of the scattering plate 10 (the direction along the normal H0 in FIG. 10B). ) With a smaller angle than the critical angle.

  Thus, the projection light coming through the gap 14h is scattered and emitted to the front side of the scattering plate 10 by the second portion 14b.

  Therefore, in the third embodiment, it is possible to prevent the incident light that is incident on the scattering plate 10 from being reflected when the light is incident at a relatively large angle that is equal to or greater than the critical angle, and the loss of light increases. It becomes. In addition, by a relatively simple configuration using the two optical elements of the first and second portions 14a and 14b, the loss of light is reduced for the incoming projection light, and the proportion of light emitted to the front side is increased. Is possible.

  Here, with respect to the first portion 14a formed as a mirror as described above, the change of the optical path by the first portion 14a is controlled by adjusting the inclination angle formed with respect to the normal direction of the scattering plate 10 on the surface. Further, in addition to or instead of this, for the second portion 14b, the concave portion is formed in a predetermined type of optical shape such as a lens or a prism, thereby controlling light scattering for each concave portion. It becomes possible. Therefore, it is possible to prevent the loss of the projection light emitted to the front side from increasing with respect to the projection light arriving from the back side of the scattering plate 10 due to reflection and scattering at the first and second portions 14a and 14b. Can do.

  Moreover, when the 1st part 14a is formed with a mirror as demonstrated above, it becomes difficult for projection light to pass through the part which becomes a shadow of the 1st part 14a in the scattering plate 10. FIG. As described above, the gap 14h is formed in a stripe shape by the first portion 14a, thereby minimizing the arrangement area of the first portion 14a, and the incident light emitted from the projector 20 is received by the first portion 14a. By being blocked, it becomes possible to prevent an increase in light loss.

  Next, a modification of the third embodiment will be described with reference to FIG. FIG. 11 is a cross-sectional view schematically showing a configuration of a cross-sectional portion of the scattering plate in a modification of the third embodiment.

  In FIG. 11, the first portion 14a has a light guide material 14ac filled in the gap 14h. In this case, for example, according to the traveling direction indicated by the arrow P4 in FIG. 11, the projection light irradiated from the projector 20 and arriving at the gap 14h is guided to and incident on the first portion 14a by the light guide material 14ac. Then, after the optical path is changed by the first portion 14a, the light is guided by the light guide material 14ac so as to be incident on the second portion 14b. Therefore, for the projection light arriving at the gap 14h, the ratio of the light incident on the first portion 14a is made larger than in the case where the light guide material 14ac is not provided, and the optical path is changed by the first portion 14a. The projected light that has traveled again travels toward the back side of the scattering plate 10 from the gap 14h, thereby preventing a situation where the loss of light increases.

  In FIG. 11, the first portion 14 a may be provided as an optical element separated from the second portion 14 b by being attached to the scattering plate 100. Moreover, the recessed part or convex part of the 2nd part 14b may be formed in the shadow in the arrangement position of the 1st part 14a. In this case, the concave portion or the convex portion arranged in the shadow of the first portion 14a is a portion that does not function as the second portion 14b.

  The present invention is not limited to the above-described embodiments, and can be appropriately changed without departing from the scope or spirit of the invention that can be read from the claims and the entire specification. A video screen device is also included in the technical scope of the present invention.

It is a figure which shows the schematic whole structure of the video display apparatus of this embodiment. FIG. 2A is a plan view schematically showing a configuration of the scattering plate, and FIG. 2B schematically shows a configuration of a cross-sectional portion taken along line X0-X0 ′ in FIG. It is sectional drawing. FIG. 3A is a cross-sectional view showing the light arriving at the scattering plate in the cross-sectional portion shown in FIG. 2B, and FIG. 3B is a comparative example in which the scattering plate is arranged. It is sectional drawing which shows the appearance of the light which arrives in a part of power transparent wall. It is a perspective view which shows the appearance of the light which arrives at a scattering plate. It is sectional drawing which shows roughly the structure of the cross-sectional part about one structure of the scattering plate in this modification. FIG. 6A and FIG. 6B are plan views schematically showing another configuration of the scattering plate in this modification. FIGS. 7A to 7D are plan views schematically showing other configurations of the scattering plate in the present modification. Fig.8 (a) is a top view shown about arrangement | positioning of the scattering part of the scattering plate in 2nd Embodiment, FIG.8 (b) is schematic about the structure of the cross-sectional part of a scattering plate about 2nd Embodiment. FIG. It is a figure which shows the arrangement | positioning relationship between the space for light passage in a scattering plate, and a projector. FIG. 10A is a cross-sectional view schematically showing the configuration of the cross-sectional portion of the scattering plate in the third embodiment, and FIG. 10B shows the light arriving at the scattering plate of the third embodiment. FIG. It is sectional drawing which shows roughly the structure of the cross-sectional part of the scattering plate in the modification of 3rd Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Scattering plate, 20 ... Projector, 100 ... Water tank, 101 ... Transparent wall

Claims (13)

A scattering plate that is built in a part of the transparent wall of the structure and capable of scattering light coming from the back side of the transparent wall toward the front side of the transparent wall;
An image display device comprising: a projection unit that irradiates projection light as the incoming light so as to form an image on the scattering plate from the back side.   The video display device according to claim 1, wherein the scattering plate includes a transparent or translucent portion and a scattering portion that scatters the incoming light.   The image display according to claim 2, wherein the scattering portion has at least one of a stripe shape, a check shape, a block shape, an island shape, and a circular shape, and is scattered in the transparent or translucent portion. apparatus.   The video display device according to claim 1, wherein the scattering plate has an uneven surface.   The image display device according to claim 4, wherein at least one of the concave portion and the convex portion has a predetermined type of optical shape on the uneven surface of the scattering plate. The projection means irradiates the projection light obliquely from the back side,
The said scattering plate is comprised so that it may scatter toward the said front side, bending the optical path of the said projection light to the side which approaches the normal line direction of the said scattering plate. The video display device according to one item. A scattering plate capable of scattering light coming from the back side toward the front side;
A projection means for irradiating projection light as the incoming light so as to form an image on the scattering plate obliquely from the back side;
The image display device, wherein the scattering plate is configured to scatter toward the front side while bending the optical path of the projection light toward the side closer to the normal direction of the scattering plate.   The scattering plate has a first portion that defines a light passage space that opens in a direction in which the projection light arrives, and directs the projection light that comes through the light passage space to the front side. The video display device according to claim 6, further comprising: a second portion that scatters. The first part has a light reflecting film that borders the periphery of the light passage space,
The video display device according to claim 8, wherein the second portion has an uneven surface that scatters the projection light that arrives by being reflected by the light reflecting film toward the front side. The first portion has a light guide material filled in the light passage space;
The video display device according to claim 8, wherein the second portion has an uneven surface that scatters the projection light that arrives by being guided by the light guide material toward the front side. The projection means irradiates the projection light from obliquely above,
The image display device according to claim 8, wherein the first portion defines a stripe-shaped gap extending in a horizontal direction as the light passage space. An image screen device in which an image is projected by irradiation with projection light,
An image screen device comprising a scattering plate which is built in a part of a transparent wall of a structure and capable of scattering light coming from the back side of the transparent wall toward the front side of the transparent wall. An image screen device in which an image is projected by irradiation with projection light,
With a scattering plate that can scatter light coming from the back side toward the front side,
The scattering plate is configured to scatter toward the front side while bending the optical path of the projection light coming obliquely from the back side toward the side approaching the normal direction of the scattering plate. Video screen device.

Images