JP2022035209A - Screen and video display device - Google Patents

Abstract

To provide a screen which has transparency, and makes a boundary between a region outside the screen adjacent to the screen when viewed from a normal direction of a screen surface and the screen inconspicuous, and a video display device.SOLUTION: A screen 10 images video light L projected from a video source LS and displays a video, and has transparency. The screen 10 includes a display area 10A having a reflecting layer 13 being an imaging layer that transmits a part of incident light and has an imaging action for displaying the video, and a non-display area 10B that is provided on the outer periphery of the display area 10A when viewed from a normal direction of a screen surface, does not have the reflecting layer 13 and does not display the video, in which the reflecting layer 13 is provided between two resin layers (first optical shape layer 12 and second optical shape layer 14) having transparency while being brought into contact with the layers.SELECTED DRAWING: Figure 2

Description

The present invention relates to a screen having transparency and an image display device including the screen.

In recent years, various transparent reflective and transmissive screens have been developed and used (see, for example, Patent Document 1). Such a transparent screen is often used by being attached to or sandwiched by a transparent glass or resin support plate or the like.

Japanese Unexamined Patent Publication No. 2017-134195

However, in a screen having such transparency, the boundary between the screen and the region outside the screen (for example, the portion of only the support plate) adjacent to the screen when viewed from the normal direction of the screen surface is due to the transmittance difference. There was a problem that it was conspicuous.

An object of the present invention is to provide a screen and an image display device which have transparency and whose boundary with an area outside the screen adjacent to the screen when viewed from the normal direction of the screen surface is inconspicuous.

The present invention solves the above-mentioned problems by the following solution means. In addition, in order to facilitate understanding, the description will be given with reference numerals corresponding to the embodiments of the present invention, but the present invention is not limited thereto.
The first invention is a screen that forms an image of image light projected from an image source to display an image and has transparency, transmits a part of the incident light, and displays the image. A display area (10A, 30A) including an image layer (13, 33) having an image forming action for forming an image, and an image layer provided on the outer periphery of the display area when viewed from the normal direction of the screen surface. It is provided with a non-display area (10B, 30B) that does not display an image and is provided in contact with the two transparent layers (12, 14, 32, 34). It is a screen (10, 20, 30) characterized by the fact that it is.
The second invention is the unit according to claim 1, wherein the incident side of the image light has a first surface (121a, 321a) and a second surface (121b, 321b) intersecting the first surface (121a, 321a). The first optical shape layer (12, 32) having an optical shape in which the optical shapes (121, 321) are arranged along the screen surface is provided, and the imaging layer (13, 33) is at least the unit optical shape. A second surface formed on a part of the first surface, having an irregular uneven shape on the surface thereof, and formed so as to fill a valley portion of the unit optical shape on which the image forming layer is formed. A screen (10, 20, 30) comprising an optical shape layer (14, 34).
A third aspect of the invention is the screen according to claim 1 or 2, wherein the image layer (13) is formed of a metal or a dielectric. be.
According to a fourth aspect of the present invention, in the screen according to claim 1 or 2, the imaging layer (33) has transparency and two adjacent transparent layers (12, 14, 32, 34) The screen (30) is characterized by having a layer having a lower refractive index.
The fifth invention relates to the non-display area (10B) of the display area (10A) when viewed from the normal direction of the screen surface in the screen according to any one of claims 1 to 4. The adjacent region is a screen (20) characterized by being a change region (20C) in which the imaging action of the image light gradually becomes smaller toward the non-display region.
A sixth aspect of the invention is the screen according to claim 5, wherein the change region (20C) becomes thinner toward the non-display region (10B). It is a screen (20).
A seventh aspect of the invention is the screen of the fifth aspect, wherein the changed area occupies a smaller area as the area having the image forming action toward the non-display area. (20).
According to an eighth aspect of the invention, in the screen according to claim 5, in the change region (20C), the image layer is formed discretely, and as the image layer is directed toward the non-display area (10B), the image layer is formed. The screen (20) is characterized in that the area occupied by the area in which the is formed is small.
The ninth invention is a video display device including any screen (10, 20, 30) from the first invention to the eighth invention, and a video source (LS) for projecting video light onto the screen. (1,3).

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a screen and an image display device which have transparency and whose boundary with an area outside the screen adjacent to the screen when viewed from the normal direction of the screen surface is inconspicuous.

It is a figure which shows the image display device 1 of 1st Embodiment. It is a figure which shows the appearance which the screen 10 of 1st Embodiment was seen from the normal direction of a screen surface. It is a figure explaining the layer structure of the screen 10 of 1st Embodiment. It is a figure explaining the 1st optical shape layer 12 of 1st Embodiment. It is a figure which shows the state of the image light and the outside light in the display area 10A of the screen 10 of 1st Embodiment. It is a figure which shows the state of the image light and the outside light in the non-display area 10B of the screen 10 of 1st Embodiment. It is a figure which shows the state which the screen 20 of the 2nd Embodiment was seen from the normal direction of the screen surface. It is a figure explaining the change area 20C of the screen 20 of the 2nd Embodiment. It is a figure which shows the other embodiment of the change area 20C of the 2nd Embodiment. It is a figure which shows the image display device 3 of the 3rd Embodiment. It is a figure which shows the state which the screen 30 of the 3rd Embodiment was seen from the normal direction of the screen surface. It is a figure explaining the layer structure of the screen 30 of 3rd Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings and the like. In addition, each figure shown below including FIG. 1 is a diagram schematically shown, and the size and shape of each part are exaggerated as appropriate for easy understanding.
In the present specification, terms that specify a shape or a geometric condition, for example, terms such as parallel and orthogonal, have the same optical function in addition to their strict meanings and can be regarded as parallel or orthogonal. The state with the error of is also included.
Further, the numerical values such as the dimensions of each member and the material names described in the present specification are examples as an embodiment, and are not limited to these, and may be appropriately selected and used.

Further, in this specification, terms such as plate and sheet are used, but as a general usage, these are used in the order of thickness, plate, sheet, and film. It is used in the same way in the book. However, since there is no technical meaning in such proper use, these words can be replaced as appropriate.
Further, in the present specification, the screen surface means a surface in the plane direction of the screen when viewed as the entire screen.

(First Embodiment)
FIG. 1 is a diagram showing a video display device 1 of the first embodiment. FIG. 1A is a perspective view of the image display device 1, and FIG. 1B is a view of the image display device 1 as viewed from the side surface side (+ X side described later).
The image display device 1 has a screen 10, an image source LS, and the like, and the image source LS projects image light and displays an image on the screen of the screen 10.
The screen 10 of the present embodiment is a reflective screen that reflects the image light L projected from the image source LS and displays the image on the screen. The details of the screen 10 will be described later.

Here, in order to facilitate understanding, in each of the figures shown below including FIG. 1, an XYZ Cartesian coordinate system is appropriately provided and shown. In this coordinate system, the left-right direction of the screen 10 is the X direction, the vertical direction of the screen is the Y direction, and the thickness direction of the screen 10 is the Z direction. The screen of the screen 10 is parallel to the XY plane, and the thickness direction (Z direction) of the screen 10 is orthogonal to the screen of the screen 10.
Further, when viewed from the observer O1 located in the front direction of the image source side of the screen 10, the direction toward the right side in the left-right direction of the screen is the + X direction, the direction toward the upper side in the vertical direction of the screen is the + Y direction, and the back side in the thickness direction ( The direction from the back surface side to the image source side is the + Z direction.
Further, in the following description, the screen vertical direction, the screen horizontal direction, and the thickness direction are the screen vertical direction (vertical direction), the screen horizontal direction (horizontal direction), and the screen vertical direction in the usage state of the screen 10, unless otherwise specified. It is assumed that it is the thickness direction (depth direction) and is parallel to the Y direction, the X direction, and the Z direction, respectively. Further, the screen surface of the screen 10 is parallel to the screen (XY surface) of the screen 10.

The image source LS is an image projection device that projects the image light L onto the screen 10, and is, for example, a short focus type projector.
The image source LS of the present embodiment is in the left-right direction of the screen of the screen 10 when the screen (display area) of the screen 10 is viewed from the front direction (normal direction of the screen surface) in the state of use of the image display device 1. It is located in the center and on the lower side (−Y side) in the vertical direction from the screen of the screen 10.
The image source LS projects the image light L diagonally in the depth direction (Z direction) from a position where the distance from the surface of the screen 10 is significantly closer than that of a general-purpose projector located in the front direction of the screen of the conventional screen. can. Therefore, as compared with the conventional general-purpose projector, the image source LS has a shorter projection distance to the screen 10 and a larger incident angle at which the projected image light L is incident on the screen 10.

FIG. 2 is a diagram showing a state in which the screen 10 of the first embodiment is viewed from the normal direction of the screen surface.
FIG. 3 is a diagram illustrating a layer structure of the screen 10 of the first embodiment. In FIG. 3, a part of a cross section that passes through a point A (see FIG. 1) that is the center of the screen (geometric center of the screen) of the screen 10 and is parallel to the arrangement direction of the unit optical shape 121 and the normal direction of the screen surface. Is enlarged and shown. FIG. 3A is an enlarged view of a part of the cross section of the screen 10 in the display area 10A. FIG. 3B is an enlarged view of a part of the cross section of the screen 10 in the non-display area 10B. In FIG. 3, the support plate 50 and the like are omitted for ease of understanding.
The screen 10 of the present embodiment has transparency, and reflects the image light L projected by the image source LS toward the observer O1 side located in the front direction of the image source side (+ Z side), and the observer. It is a reflective screen that displays an image on O1.

The screen 10 is a sheet-like member whose both sides are flat, and is a display area 10A for displaying an image and a non-display area 10B for not displaying an image when viewed from the normal direction (Z direction) of the screen surface. Has. The non-display area 10B is located on the outer periphery of the display area 10A and is adjacent to the display area 10A in the present embodiment.
The display area 10A of the screen 10 has a substantially rectangular shape in which the long side direction is the left-right direction of the screen when viewed from the observer O1 side in the used state, and a band-shaped non-display area 10B is provided along the four sides thereof. .. The display area 10A of the screen 10 has a screen size of about 40 to 100 inches diagonally and a screen aspect ratio of 16: 9.

Further, the width of the non-display area 10B located at both ends of the screen 10 in the left-right direction (X direction) and extending in the up-down direction (Y direction) of the screen is W1, and the width of the portion extending in the up-down direction (Y direction) of the screen is W1. The width of the portions located at both ends (Y direction) and extending in the left-right direction (X direction) of the screen is W2. In the present embodiment, the non-display area 10B has the same width and will be described with reference to an example in which W1 = W2, but may be appropriately changed depending on the usage environment and the like.
Not limited to this, the screen 10 may have another shape, for example, the shape seen from the observer O1 side, or the screen size may be 40 inches or less, such as the purpose of use and the environment of use. The size and shape thereof can be appropriately selected according to the above.

In general, the screen 10 is a laminate of thin layers made of resin or the like, and often does not have sufficient rigidity to maintain flatness by itself. Therefore, as shown in FIG. 1 and the like, the screen 10 of the present embodiment is integrally joined (or partially fixed) to the support plate 50 via the joining layer 51 on the back surface side (−Z side), and the flatness of the screen is obtained. Is maintained.
The support plate 50 is a flat plate-shaped member having transparency and high rigidity, and a plate-shaped member made of a resin such as acrylic resin or PC (polycarbonate) resin or made of glass can be used. Further, the bonding layer 51 is also formed by a transparent adhesive, an adhesive, or the like. In FIG. 1 and the like, the screen 10 and the support plate 50 are shown to have the same size for easy understanding, but in the present embodiment, the support plate 50 is larger than the screen 10 and the normal of the screen surface. When viewed from the direction (Z direction), the area outside the screen adjacent to the screen 10 is the area of only the support plate 50.

The plate surface of the support plate 50 (the surface of the support plate 50 in the plane direction when viewed as a whole) is parallel to the screen surface.
If the screen 10 has sufficient rigidity, it is not attached to the support plate 50, and the lower (-Y side) end or upper side (+ Y side) of the screen 10 in the vertical direction (Y direction) of the screen 10 is not attached. ) Only the end portion may be supported by a support member (not shown), and the screen 10 may be arranged upright in the vertical direction (Y direction).

As shown in FIG. 3A, the display area 10A of the screen 10 has the base material layer 11, the first optical shape layer 12, and the reflection in order from the image source side (+ Z side) in the thickness direction (Z direction). It includes a layer 13, a second optical shape layer 14, and a protective layer 15.
On the other hand, as shown in FIG. 3B, the non-display region 10B of the screen 10 has the base material layer 11, the first optical shape layer 12, and the second optical shape layer 14 in this order from the image source side (+ Z side). It has a protective layer 15, but does not have a reflective layer 13. In FIG. 3B, the boundary between the first optical shape layer 12 and the second optical shape layer 14 is shown by a two-dot chain line for ease of understanding.
Hereinafter, first, each layer of the display area 10A will be described.

The base material layer 11 is a sheet-like member having light transmission, and the first optical shape layer 12 is integrally formed on the back surface side (−Z side) thereof. The base material layer 11 is a layer that serves as a base material (base) that forms the first optical shape layer 12.
The base material layer 11 is, for example, a polyester resin such as PET (polyethylene terephthalate) having high light transmittance, an acrylic resin, a styrene resin, an acrylic / styrene resin, a PC (polycarbonate) resin, an alicyclic polyolefin resin, and a TAC (tri). Acrylic cellulose) Formed from resin or the like.

FIG. 4 is a diagram illustrating the first optical shape layer 12 of the first embodiment. FIG. 4 shows a state in which the first optical shape layer 12 is viewed from the back surface side (−Z side). In order to facilitate understanding, the reflective layer 13 and the like are omitted, and only the first optical shape layer 12 is shown. Is shown.
The first optical shape layer 12 is a light-transmitting layer formed on the back surface side (−Z side) of the base material layer 11. A plurality of unit optical shapes (unit lenses) 121 are arranged and provided on the back surface (−Z side) surface of the first optical shape layer 12.
As shown in FIG. 4, the unit optical shape 121 is a partial shape (arc shape) of a perfect circle, and a plurality of unit optical shapes 121 are arranged concentrically around a point C located outside the screen (display area) of the screen 10. ing. That is, the first optical shape layer 12 has a circular Fresnel lens shape having a so-called offset structure centered on the point C (Fresnel center) on the surface on the back surface side thereof.

In the present embodiment, as shown in FIG. 4, when the first optical shape layer 12 is viewed from the back surface side (-Z side) along the normal direction of the screen surface, the point C is the screen left-right direction (X). It is located in the center of the screen (direction) and below the outside of the screen (-Y side), and the points C and A are located on the same straight line extending in the vertical direction (Y direction) of the screen.

As shown in FIG. 3A, the unit optical shape 121 is parallel to the direction orthogonal to the screen surface (Z direction), and the cross-sectional shape in the cross section parallel to the arrangement direction of the unit optical shape 121 is substantially triangular. The shape.
The unit optical shape 121 is convex toward the back surface side (-Z side), and has a first slope (lens surface) 121a on which image light is incident and a second slope (non-lens surface) 121b intersecting the first slope (lens surface) 121a. ing. In one unit optical shape 121, the first slope 121a is located on the upper side (+ Y side) of the second slope 121b with the apex t interposed therebetween.

The first slope 121a and the second slope 121b of the unit optical shape 121 are rough surfaces having fine and irregular uneven shapes. The fine uneven shape is formed by irregularly arranging the convex shape and the concave shape in the two-dimensional direction, and the convex shape and the concave shape have irregular sizes, shapes, heights, and the like.

The arrangement pitch of the unit optical shape 121 is P, and the height of the unit optical shape 121 (the dimension from the apex t in the thickness direction of the screen 10 to the point v which is the valley bottom between the unit optical shapes 121) is h. be.
Further, the angle formed by the first slope 121a with the plane parallel to the screen plane (XY plane) is θ1. The angle formed by the second slope 121b with the surface parallel to the screen surface is θ2. The angles θ1 and θ2 satisfy the relationship θ2> θ1.

In the present embodiment, the arrangement pitch P is preferably 50 μm or more and 500 μm or less. When the arrangement pitch P is less than 50 μm, it becomes difficult to manufacture the unit optical shape 121 that realizes the desired optical performance, and the production cost increases, which is not preferable. Further, when the arrangement pitch P is larger than 500 μm, the unit optical shape 121 may be visually recognized in a streak pattern when the observer O1 or the like observes the screen 10, which is not preferable. Therefore, the arrangement pitch P is preferably in the above range.

Further, the angle θ1 is preferably 5 ° or more and 30 ° or less. When the angle θ1 is less than 5 ° or larger than 30 °, the observer O1 is good due to the reflective layer 13 formed in the unit optical shape 121, although it depends on the refractive index of the first optical shape layer 12. It is not preferable because it becomes difficult to reflect the image light in a direction in which the image can be visually recognized. Therefore, the angle θ1 is preferably in the above range.
The numerical range of the angle θ1 and the arrangement pitch P1 is preferably the above range, but can be appropriately changed depending on the environment in which the screen 10 is installed and the like.

For ease of understanding, FIG. 3 and the like show an example in which the arrangement pitch P and the angles θ1 and θ2 of the unit optical shape 121 are constant in the arrangement direction of the unit optical shape 121. However, in the unit optical shape 121 of the present embodiment, the arrangement pitch P is actually constant, but the angle θ1 gradually increases as the angle θ1 moves away from the point C which becomes the Fresnel center in the arrangement direction of the unit optical shape 121. ..
Not limited to this, the angle θ1 may be constant, or the arrangement pitch P may gradually change along the arrangement direction of the unit optical shape 121. Further, the arrangement pitch P, the angle θ1 and the like may be changed stepwise along the arrangement direction of the unit optical shape 121.
The angles θ1 and θ2, the arrangement pitch P, and the like are the projection angle of the image light from the image source LS (angle of the image light incident on the screen 10), the size of the pixels of the image source LS, and the screen of the screen 10. It may be appropriately set according to the size, the refractive index of each layer, and the like.

In the present embodiment, an example in which a circular Fresnel lens shape is formed on the back surface (−Z side) of the first optical shape layer 12 is shown, but the present invention is not limited to this, and the first optical shape layer is not limited to this. A form in which a unit optical shape (unit lens) 121 extends in the left-right direction (X direction) of the screen and a linear Fresnel lens shape arranged in the vertical direction (Y direction) of the screen is formed on the surface on the back side of the twelve. May be. Further, the unit prism having a substantially triangular cross-sectional shape and extending in the left-right direction (X direction) of the screen as the ridge line direction may be arranged in the vertical direction (Y direction) of the screen as the unit optical shape.

The first optical shape layer 12 is formed of an ultraviolet curable resin such as urethane acrylate-based, polyester acrylate-based, epoxy acrylate-based, polyether acrylate-based, polythiol-based, and butadiene acrylate-based resin having high light transmittance.
In the present embodiment, the ultraviolet curable resin will be described as an example of the resin forming the first optical shape layer 12, but the present invention is not limited to this, and for example, other ionizing radiation such as an electron beam curable resin is used. It may be formed of a curable resin.

The reflective layer 13 is an image forming layer that forms an image of image light. The reflective layer 13 is a so-called semi-transmissive reflective layer that reflects a part of the incident light and transmits a part of the incident light, and is a so-called half mirror. The reflective layer 13 is formed on at least a part of the first slope 121a.
In the present embodiment, as shown in FIG. 3A, the reflective layer 13 is formed on the first slope 121a and the second slope 121b, but is not limited to this, and is formed only on the first slope 121a. The form may not be formed on the second slope 121b.

As described above, the first slope 121a and the second slope 121b are rough surfaces on which fine and regular uneven shapes are formed, and the reflective layer 13 is formed following the fine uneven shapes. The film is formed while maintaining the uneven shape of the first slope 121a and the second slope 121b. Therefore, the surface of the reflective layer 13 on the image source side (+ Z side) (the surface on the first optical shape layer 12 side) and the surface on the back surface side (−Z side) (the surface on the second optical shape layer 14 side) are It is a matte surface (rough surface) having a fine and irregular uneven shape.
The reflective layer 13 has a function of diffusing and reflecting a part of the incident light due to the fine and irregular uneven shape of the surface thereof, and transmitting at least a part of the incident light without diffusing. There is.

The ratio of the reflectance and the transmittance of the reflective layer 13 can be appropriately set, but the image light is reflected well and the light other than the image light (for example, the light from the outside such as the background light) is satisfactorily transmitted. From the viewpoint, the light transmittance of the reflective layer 13 alone (the total light transmittance of the light incident on the reflective layer 13 at an incident angle of 0 °) is 30% or more and 80% or less, and the light transmittance of the reflective layer 13 alone. (That is, it is desirable that the transmittance of the light incident on the screen surface of the screen 10 at an incident angle of 0 ° only by the reflective layer 13) is in the range of 3% or more and 60% or less.
The reflective layer 13 is made of a metal having high light reflectivity, for example, aluminum, silver, nickel, or the like, and its thickness is, for example, about several tens of Å. Not limited to this, the reflective layer 13 may be formed, for example, by sputtering a metal having high light reflectivity, transferring a metal foil, applying a paint containing a metal thin film, or the like.

The reflective layer 13 of the present embodiment is formed by depositing aluminum on the first slope 121a and the second slope 121b of the unit optical shape 121. The transmittance of the reflective layer 13 of the present embodiment alone is about 50%, and the reflectance is about 5%.
Further, the reflective layer 13 may be formed by depositing a dielectric multilayer film or a dielectric single layer film which has high transparency, has a small light absorption loss, and can realize a high reflectance.

The second optical shape layer 14 is a layer having light transmittance provided on the back surface side (−Z side) of the reflection layer 13. The second optical shape layer 14 is formed so as to fill the valley portion between the unit optical shapes 121, and the surface on the back surface side (−Z side) thereof is planar. Therefore, the surface of the second optical shape layer 14 on the image source side (+ Z side) is formed by arranging a plurality of substantially inverted unit optical shapes of the unit optical shape 121 of the first optical shape layer 12.
By providing such a second optical shape layer 14, the reflective layer 13 can be protected, the protective layer 15 and the like can be easily laminated on the back surface (−Z side) surface of the screen 10, and the support layer 15 and the like can be easily laminated. It also facilitates joining to the plate 50 and the like.

The refractive index of the second optical shape layer 14 is equal to or substantially the same as that of the first optical shape layer 12 (the difference in refractive index is small enough to be regarded as equivalent) from the viewpoint of enhancing the transparency of the screen 10. preferable.
Further, the second optical shape layer 14 can be formed of the same material as the first optical shape layer 12 described above.
The second optical shape layer 14 of the present embodiment is formed by using the same ultraviolet curable resin as the first optical shape layer 12, and the first optical shape layer 12 and the second optical shape layer 14 have a refractive index. Are equal.

The protective layer 15 is a layer formed on the back surface side (−Z side) of the second optical shape layer 14, and has a function of protecting the back surface side of the screen 10.
As the protective layer 15, a resin sheet-like member having high light transmission is used. As the protective layer 15, for example, a sheet-shaped member formed by using the same material as the above-mentioned base material layer 11 may be used.

As described above, in the present embodiment, the screen 10 does not contain a diffusing material such as particles having an action of diffusing light (diffusing action).
Further, in the display area 10A of the screen 10 of the present embodiment, the image light is diffusely reflected by the fine and irregular uneven shape of the reflective surface of the reflective layer 13 and directed toward the observer O1 side. On the other hand, the light transmitted through the reflective layer 13 is not diffused and is transmitted through the display area 10A of the screen 10 to the back surface side (−Z side).

Next, the non-display area 10B of the screen 10 will be described.
As shown in FIG. 3B, the non-display region 10B includes a base material layer 11, a first optical shape layer 12, a second optical shape layer 14, and a protective layer 15 in this order from the image source side (+ Z side). ing.
In the non-display region 10B, the reflective layer 13 is not formed, and the first optical shape layer 12 and the second optical shape layer 14 are in contact with each other and are integrally laminated.
In the present embodiment, the first optical shape layer 12 and the second optical shape layer 14 are formed by using the same ultraviolet curable resin, and as described above, in FIG. 3B, two layers are formed by a two-dot chain line. However, in reality, the boundary between the first optical shape layer 12 and the second optical shape layer 14 cannot be visually recognized. In FIG. 3B, the fine and irregular uneven shapes of the first slope 121a and the second slope 121b of the unit optical shape 121 are omitted for ease of understanding.

The screen 10 of the present embodiment is formed by, for example, the following manufacturing method.
By a UV molding method, a base material layer 11 is prepared, laminated on one surface of a molding mold having a unit optical shape 121 filled with an ultraviolet curable resin, and irradiated with ultraviolet rays to cure the resin. The first optical shape layer 12 is formed. At this time, fine and irregular uneven shapes are formed on the surfaces forming the first slope 121a and the second slope 121b of the molding die that shape the unit optical shape 121. This fine and irregular uneven shape is formed by repeating plating under different conditions two or more times or performing an etching process on the surface forming the first slope 121a and the second slope 121b of the molding die. can.
After the first optical shape layer 12 is formed on one surface of the base material layer 11, the reflective layer 13 is formed on the first slope 121a and the second slope 121b in the region corresponding to the display region 10A by vapor deposition or the like. At this time, the region corresponding to the non-display region 10B is protected by masking tape or the like so that the reflective layer 13 is not formed.

After that, the ultraviolet curable resin is applied from above the low refractive index layer 33 so as to fill the valley portion between the unit optical shapes 121 so as to be flat, and the protective layer 15 is laminated to form the ultraviolet curable resin. It is cured to integrally form the second optical shape layer 14 and the protective layer 15. After that, the screen 10 is completed by cutting it to a predetermined size or the like.
The base material layer 11 and the protective layer 15 may be in the form of a single leaf or in the form of a web.

As described above, the display region 10A has the reflective layer 13, but the non-display region 10B does not have the reflective layer 13. Therefore, among the light that is incident from the normal direction of the screen surface (incident with respect to the screen surface at an incident angle of 0 °) and transmitted through the screen 10, the light emitted at an emission angle of 0 ° (that is, the screen 10 without being diffused). The ratio of the light transmitted through the display area 10B is larger in the non-display area 10B than in the display area 10A. The larger the ratio of the light emitted at the emission angle of 0 °, the higher the transparency.

In the display region 10A, the ratio of the light having an emission angle of 0 ° to the light incident on the screen surface at an incident angle of 0 ° and transmitted through the display region 10A is 75% or less. On the other hand, in the non-display region 10B, the ratio of the light having an emission angle of 0 ° to the light incident on the screen surface at an incident angle of 0 ° and transmitted through the non-display region 10B is 85% or more. be.
Therefore, since the non-display area 10B has a higher transmittance of external light or the like than the display area 10A, the transparency when observing the other side through the screen 10 is high.

Further, depending on the presence or absence of the reflective layer 13, the light reflectance (total light reflectance) of the display region 10A is higher than that of the non-display region 10B, and in particular, the light incident on the screen surface at an incident angle of 45 °. The reflectance (total light reflectance) is large. The difference in reflectance of light incident on the screen surface at an incident angle of 45 ° is 5% or more in the display area 10A and larger than that in the non-display area 10B. The light incident on the screen surface at an incident angle of 45 ° is light incident on the screen surface from the image source side along the arrangement direction of the unit optical shape 121 in the direction formed by 45 ° in the normal direction of the screen surface. It is assumed that the light is based on the above, and the same applies to the following specification.
Therefore, since the reflectance of light in the non-display area 10B is smaller than that in the display area 10A, the contrast of the transmitted image when observing the other side through the screen 10 is also high.
Therefore, the transmitted image when observing the other side through the screen 10 is better in the non-display area 10B than in the display area 10A.

Further, in the region outside the screen adjacent to the screen 10 (in the present embodiment, the region of only the support plate 50), since the screen 10 itself is not present, the screen surface is compared with the display region 10A and the non-display region 10B. The proportion of light that is incident at an incident angle of 0 ° and is transmitted through the support plate 50 and emitted at an emission angle of 0 ° is high, and the reflectance of light is low regardless of the incident angle on the plate surface. .. When the region outside the screen adjacent to the outer edge of the screen 10 when viewed from the normal direction of the screen surface is an air layer, the transmitted light or the reflected light itself does not exist.
As a result, the display area 10A to the non-display area 10B of the screen 10 joined to the support plate 50, and the area outside the screen 10 adjacent to the screen 10 when viewed from the normal direction of the screen surface (in the present embodiment, the support plate 50). The transmittance gradually increases toward the region of only), and the reflectance of light gradually decreases regardless of the angle of incidence, so that the boundary between the screen 10 and the region outside the screen becomes less noticeable. be able to.

FIG. 5 is a diagram showing the state of video light and external light in the display area 10A of the screen 10 of the first embodiment.
FIG. 6 is a diagram showing the state of video light and external light in the non-display area 10B of the screen 10 of the first embodiment.
In FIGS. 5 and 6, a part of the cross section in the cross section parallel to the arrangement direction of the unit optical shape 121 and the thickness direction (Z direction) of the screen, passing through the point A at the center of the screen, is shown schematically in an enlarged manner. ing. Further, in FIGS. 5 and 6, in order to facilitate understanding, the support plate 50 and the like are omitted, and further, it is shown that there is no difference in the refractive index at the interface of each layer in the screen 10. Further, in FIG. 6, for ease of understanding, the fine and irregular uneven shapes of the first slope 121a and the second slope 121b of the unit optical shape 121 are omitted.

First, the video light incident on the display area 10A of the screen 10 will be described.
As shown in FIG. 5, in the display area 10A, a part of the image light L2 of the image light L1 projected from the image source LS (see FIG. 1) located below the screen 10 and incident on the screen 10 is. It is incident on the first slope 121a of the unit optical shape 121, diffusely reflected by the reflection layer 13, formed into an image, and emitted to the observer O1 side.

Of the video light incident on the first slope 121a, the other video light L3 that has not been reflected passes through the reflection layer 13 and is emitted from the back surface side (−Z side) of the display area 10A of the screen 10. At this time, the image light L3 emits light toward the upper side (+ Y side) of the screen 10 and does not reach the observer O2 located in the front direction on the back side of the screen 10.
Further, of the video light L1 projected from the video source LS, a part of the video light L4 is reflected on the surface of the screen 10 of the display area 10A, but is directed toward the upper side (+ Y side) of the screen 10, so that the observer O1 can see it. It does not interfere with the visibility of the image.

In the present embodiment, the image light L1 is projected from below the screen 10, and the angle θ2 (see FIG. 3) is larger than the incident angle of the image light at each point in the vertical direction of the screen of the screen 10. The light does not directly enter the second slope 121b, and the second slope 121b has almost no effect on the reflection of the image light.

Next, regarding light from the outside world (hereinafter referred to as external light) such as background light other than the image light incident on the display area 10A of the screen 10 from above the back side (-Z side) or the image source side (+ Z side). explain.
As shown in FIG. 5, of the external light G1 and G5 incident on the display area 10A of the screen 10 from above, some of the external light G2 and G6 are reflected by the surface of the screen 10 and head toward the lower side of the screen. Further, of the external light G1, a part of the external light G3 is reflected by the reflection layer 13, and a part of the external light G1 is emitted downward to the screen 10 or totally reflected on the surface of the screen 10 on the image source side (+ Z side). Then, it goes downward in the screen 10 and attenuates. Of the external light G5, a part of the external light G7 is reflected by the reflective layer 13 and emitted to the upper side of the screen 10 on the back side (−Z side). Further, the other external light G4 and G8 transmitted through the reflective layer 13 pass through the reflective layer 13 and are emitted to the lower side of the back surface side and the lower side of the image source side of the screen 10, respectively. At this time, since the external light G2, G8, etc. heading downward on the image source side do not reach the observer O1, the contrast decrease of the image due to the external light can be suppressed.

Although not shown, a part of the external light incident on the display area 10A of the screen 10 from the image source side (+ Z side) and the back side (−Z side) is the back side of the display area 10A of the screen 10 and the image source. Total internal reflection on the side surface, downwards in the screen and decaying.
Further, other external light G9 and G10 incident on the display region 10A of the screen 10 at a small incident angle are partially (not shown) reflected at the interface between the screen 10 and air and the reflective layer 13, but most of them are reflected. It passes through the reflective layer 13 and emits light to the back surface side (−Z side) and the image source side (+ Z side), respectively.

In the present embodiment, since the reflective layer 13 does not diffuse the transmitted light, the external light G9 and G10 transmitted through the display area 10A of the screen 10 are not diffused. Therefore, when observing the scenery on the other side of the screen 10 through the display area 10A of the screen 10, the scenery on the other side of the screen 10 is observed with high transparency without blurring or bleeding white. be able to.

The screen 10 of the present embodiment has no diffusing action except that the surface of the reflective layer 13 has a fine and irregular uneven shape, and the image light is diffused only when reflected by the reflective layer 13. Further, in the screen 10 of the present embodiment, only the light reflected by the reflective layer 13 is diffused, and the transmitted light is not diffused.
Therefore, the screen 10 of the present embodiment can display an image having a good viewing angle and resolution in the display area 10A, and the scenery on the other side of the screen 10 is observed without blurring or blurring. It is well visible to the person O1 and high transparency can be realized.

Further, in the screen 10 of the present embodiment, the observer O1 can partially see the scenery on the other side (back side) of the screen 10 even when the image light is projected on the screen 10.
Further, in the screen 10, the observer O2 located on the back side has high transparency in the scenery on the image source side (+ Z side) through the display area 10A of the screen 10 regardless of the presence or absence of projection of the image light. It can be visually recognized well.

Next, the non-display area 10B of the screen 10 will be described.
The non-display region 10B does not have the reflective layer 13. Further, the first optical shape layer 12 and the second optical shape layer 14 are formed of the same material and have the same refractive index, and are integrally laminated in contact with each other in the non-display region 10B. Therefore, as shown in FIG. 6, the external light G21, G24 and the image light L21 incident on the non-display region 10B of the screen 10 are partially reflected at the interface between the screen 10 and the air (external light G23, G26). , Image light L23), most of which pass through the screen 10 (external light G22, G25, image light L22).
At this time, the external light G22, G25 and the image light L22 transmitted through the non-display area 10B go downward or upward of the screen 10 and do not reach the observers O1 and O2. In the non-display area 10B, the image light is not formed and the image is not displayed.

Further, other external light G27 and G28 incident on the non-display area 10B of the screen 10 at a small incident angle are partially (not shown) reflected at the interface between the screen 10 and air, but most of them are in the non-display area. It passes through 10B and emits light to the back surface side (-Z side) and the image source side (+ Z side), respectively.
Therefore, when the scenery on the other side of the screen 10 is observed through the non-display area 10B of the screen 10, it can be observed with high transparency.

As described above, since the non-display region 10B does not have the reflective layer 13 as compared with the display region 10A, the light transmittance is high. On the other hand, the non-display region 10B has a plurality of resin layers (base material layer 11, first optical shape layer 12, and second optical shape layer) as compared with the region outside the screen (only the support plate 50 in this embodiment). Since 14 and the protective layer 15) are provided, the transmittance is lowered due to reflection loss between layers, absorption by the resin, and the like.
Therefore, for example, in a state where the image light is not projected, the display area 10A and the non-display area 10B of the screen 10 have transparency, and the scenery on the other side of the screen 10 and the support plate 50 can be visually recognized. However, the light transmittance (incident angle 0 ° with respect to the screen surface is incident on the screen 10 in this order) of the display area 10A, the non-display area 10B, and the area outside the screen (only the support plate 50 in this embodiment) is applied to the screen 10. Since the proportion of the transmitted light that is emitted at an emission angle of 0 °) is high, the boundary between the screen 10 and the area outside the screen adjacent to the screen 10 when viewed from the normal direction of the screen surface. The change in the light transmittance of the portion becomes gradual, and the boundary between the screen 10 and the area outside the screen becomes inconspicuous.

Further, the reflectance for external light and video light decreases in the order of the display area 10A, the non-display area 10B, and the area outside the screen (only the support plate 50 in this embodiment). The change in the amount of reflected light at the boundary portion of the screen becomes gradual, and the boundary between the screen 10 and the region outside the screen becomes inconspicuous.

On the other hand, in the conventional screen having no non-display area 10B, since the display area 10A extends to the outer edge portion of the screen, the screen (display area 10A) and the outside of the screen (only the support plate 50 in this embodiment). The difference in light transmittance from the region is large, and the change is steep.
Further, in the conventional screen, since the display area 10A extends to the outer edge portion of the screen, the reflectance of light between the screen (display area 10A) and the area outside the screen (only the support plate 50 in this embodiment). The difference is also large, and the change is steep.
Therefore, in the conventional screen, the boundary between the screen and the area outside the screen becomes conspicuous.

Therefore, since the screen 10 of the present embodiment has the non-display area 10B, the screen 10 and the outside of the screen 10 (in the present embodiment, the support plate 50) are compared with the conventional screen having no non-display area 10B. Only) The boundary with the area is inconspicuous.

Further, in general, the reflective layer 13 is made of a different material from the first optical shape layer 12 and the second optical shape layer 14, so that there is a possibility that peeling may occur between the layers. For example, in the present embodiment, the reflective layer 13 is aluminum, and the first optical shape layer 12 and the second optical shape layer 14 are ultraviolet curable resins. Such peeling between layers made of different materials is particularly likely to occur at the outer edge of the screen 10, leading to a significant deterioration in screen quality, which is not preferred.
However, in the present embodiment, the non-display region 10B is provided in the portion serving as the outer edge portion of the screen 10, and in the non-display region 10B, the first optical shape layer 12 and the second optical shape layer 14 are laminated. Since they are integrated together, damage to the reflective layer 13 and deterioration of the quality of the screen 10 due to such peeling and the like can be significantly reduced.
Even when the reflective layer 13 is formed of a dielectric multilayer film, a dielectric single-layer film, or the like, it is possible to suppress deterioration of the quality of the screen 10 due to peeling or peeling as described above.

From the above, according to the present embodiment, the boundary between the screen 10 and the outside of the screen becomes inconspicuous while maintaining the transparency, so that the screen 10 and the image display device 1 having higher design can be obtained. ..
Further, according to the present embodiment, the screen 10 has a non-display region 10B in which the first optical shape layer 12 and the second optical shape layer 14, which are resins, are integrally laminated on the outer periphery of the display region 10A. Since the reflective layer 13 is not exposed on the end surface of the screen 10, peeling between the reflective layer 13 and the first optical shape layer 12 and the second optical shape layer 14 and the reflective layer 13 are likely to occur on the end surface of the screen 10. Peeling between the screens can be significantly suppressed, and damage to the reflective layer 13 and deterioration of the quality of the screen 10 can be suppressed.

(Second Embodiment)
FIG. 7 is a diagram showing a state in which the screen 20 of the second embodiment is viewed from the normal direction of the screen surface.
FIG. 8 is a diagram illustrating a change region 20C of the screen 20 of the second embodiment. In FIG. 8, as an example, the change region 20C passing through the point A and parallel to the arrangement direction of the unit optical shape 121 and the normal direction of the screen surface (change region 20C located on the upper side of the display region 10A in the vertical direction of the screen). ) Is shown. Further, in FIG. 8, layers other than the first optical shape layer 12, the reflection layer 13, and the second optical shape layer 14 are omitted for ease of understanding.
The screen 20 of the second embodiment is different from the screen 10 of the first embodiment in that the area adjacent to the non-display area 10B of the display area 10A is the change area 20C. It has the same form as 10.
Therefore, the same reference numerals or the same reference numerals are given to the portions that perform the same functions as those of the first embodiment described above, and duplicate description will be omitted as appropriate.

The screen 20 has a change region 20C in a region adjacent to a non-display region 10B which is an outer edge of the display region 10A when viewed from the normal direction (Z direction) of the screen surface. This screen 20 can be applied to the image display device 1 shown in the first embodiment described above.
The layer structure of the display area 10A and the non-display area 10B of the screen 20 is the same as that of the first embodiment described above.
The change region 20C is a region in which the ratio of the light emitted at an emission angle of 0 ° to the light incident at an incident angle of 0 ° and transmitted through the screen 20 increases toward the non-display region 10B side along the screen surface. Is.

The change region 20C has a band shape and is provided at a position adjacent to the non-display region 10B on the outer edge of the display region 10A. In the present embodiment, as shown in FIG. 7, the outer edge portion of the display area 10A is the change area 20C, and the non-display area 10B is located on the outer periphery thereof. Therefore, the outer circumference of the change region 20C is in contact with the non-display region 10B.
The width of the change region 20C located near both ends of the screen 20 in the horizontal direction (X direction) and extending in the vertical direction (Y direction) of the screen is W3, and is near both ends of the screen 20 in the vertical direction (Y direction). The width of the change region 20C that is located and extends in the left-right direction (X direction) of the screen is W4. In the present embodiment, the change region 20C has the same width and will be described with reference to an example in which W3 = W4, but the present invention is not limited thereto.
In the present embodiment, as shown in FIG. 8, an example in which the thickness of the reflective layer 13 gradually becomes thinner in the changing region 20C toward the non-display region 10B side will be described.

The reflective layer 13 of the present embodiment is the same as the reflective layer 13 of the first embodiment, and is formed by depositing aluminum. Further, the reflective layer 13 adjusts the thickness of the vapor-deposited film to the region corresponding to the change region 20C by using a shielding plate or the like when the vapor deposition is performed on the unit optical shape 121, and the reflective layer 13 has the reflective layer of the change region 20C. 13 is formed so as to become thinner toward the non-display region 10B side.
As a result, the reflectance of the light reflected by the reflective layer 13 in the changing region 20C gradually decreases toward the non-display region 10B along the screen surface. Further, as the direction from the display area 10A to the non-display area 10B via the change area 20C, the proportion of the light that is incident at the incident angle of 0 ° and passes through the screen 10 and is emitted at the emission angle of 0 ° increases. ..

From the above, according to the present embodiment, in addition to achieving the same effect as that of the first embodiment, the display area 20C is further provided in the area adjacent to the non-display area 10B of the display area 10A. The boundary between the 10A and the non-display area 10B is also less noticeable, and the boundary between the screen 20 and the outside of the screen is less noticeable.

(Other embodiments of the second embodiment)
FIG. 9 is a diagram showing another embodiment of the change region 20C of the second embodiment. 9 (a) and 9 (c) show an enlarged part of a cross section parallel to the arrangement direction of the unit optical shape 121 and the thickness direction of the screen 20 in the change region 20C, and FIG. 9 (b) shows the screen. The first optical shape layer 12 and the reflective layer 13 seen from the back surface side (−Z side) of 20 are shown.
As shown in FIG. 9, in the change region 20C, the area occupied by the region where the reflective layer 13 is formed discretely and the reflective layer 13 is formed becomes smaller toward the non-display region 10B. It may be in the form.

That is, as shown in FIGS. 9A and 9B, in the changing region 20C, the reflective layer 13 is formed in, for example, a circular shape, and the formed area becomes smaller toward the non-display region 10B. May be. 9 (a) and 9 (b) show an example in which the reflective layer 13 of the change region 20C has a circular shape, but the present invention is not limited to this, and may be a polygonal shape such as a rectangular shape, or may be a streak or the like. It may be good, and it is not particularly limited. The circular shape of the reflective layer 13 may be small in area, may be formed in a small number, or may be a combination of these. Further, the positions of the reflective layers 13 may be arranged with regularity or may be irregular.
When forming such a reflective layer 13, for example, a method of masking or the like with a masking material or the like having a plurality of holes formed in the region corresponding to the change region 20C to perform vapor deposition or the like can be mentioned.

Further, as shown in FIG. 9 (c), in the change region 20C, after the reflective layer 13 is formed in the same manner as in the display region 10A, the reflective layer 13 and a part of the unit optical shape 121 are partially formed, for example, streaks. The area occupied by the reflective layer 13 may be reduced. At this time, it is preferable to delete only the reflective layer 13, but a part of the unit optical shape 121 may also be scraped together with the reflective layer 13. The shape to be deleted is not limited to the streak shape, and may be appropriately selected.

(Third Embodiment)
FIG. 10 is a diagram showing a video display device 3 according to a third embodiment. FIG. 10 shows a state in which the image display device is viewed from the side surface side (+ X side).
FIG. 11 is a diagram showing a state in which the screen 30 of the third embodiment is viewed from the normal direction of the screen surface.
FIG. 12 is a diagram illustrating a layer structure of the screen 30 of the third embodiment. In FIG. 12, a part of the cross section of the display area 30A of the screen 30 is enlarged and shown, and the cross section of the display area 30A of the screen 30 shown in FIG. 12 is the cross section of the screen 10 of the first embodiment shown in FIG. It corresponds to the cross section of the display area 10A.
The screen 30 of the third embodiment is different from the screen 10 of the first embodiment described above in that it is a transmissive screen having transparency. Therefore, the same reference numerals or common reference numerals are given to the portions that perform the same functions as those of the above-described first embodiment, and duplicate description will be omitted.

The video display device 3 of the third embodiment includes a screen 30 and a video source LS. The video source LS is the same as the video source LS of the first embodiment described above. The screen 30 is a transmissive screen that forms an image of the image light L projected from the image source LS and transmits the image through the screen 30 to display the image.
In the present embodiment, in the thickness direction (Z direction) of the screen 30, the image source LS is located on one side of the screen 30 and the observer O3 is located on the other side. In the present embodiment, the image source side where the image source LS is located is the + Z side with respect to the screen 30, and the observer O3 is located on the −Z side which is the back side.

The screen 30 is a transmissive screen having transparency, both sides thereof are flat, and the screen 30 is joined to the support plate 50 via the bonding layer 51 on the back surface side (−Z side) surface. The screen 30 has a band-shaped non-display area 30B adjacent to the display area 30A on the outer periphery of the display area 30A when viewed from the normal direction (Z direction) of the screen surface.
The screen size and the shape of the display area 30A in a plan view are the same as those of the display area 10A of the first embodiment. Further, the width of the non-display area 30B located at both ends of the screen 30 in the left-right direction (X direction) of the screen and extending in the up-down direction (Y direction) of the screen is W5, and both ends of the screen 30 in the up-down direction (Y direction) of the screen 30. The width of the non-display area 30B that is located and extends in the left-right direction (X direction) of the screen is W6. In the present embodiment, the non-display area 30B has the same width and will be described with reference to an example in which W5 = W6, but the present invention is not limited thereto.
Further, also in the present embodiment, the support plate 50 is larger than the screen 30 when viewed from the normal direction (Z direction) of the screen surface, and the region outside the screen adjacent to the screen 30 is the region of only the support plate 50. ..

The display region 30A includes a base material layer 11, a first optical shape layer 32, a low refractive index layer 33, a second optical shape layer 34, and a protective layer 15 in this order from the image source side (+ Z side). Further, the non-display region 30B includes a base material layer 11, a first optical shape layer 32, a second optical shape layer 34, and a protective layer 15 in this order from the image source side (+ Z side). That is, the non-display region 30B does not have the low refractive index layer 33 as the image forming layer.
The first optical shape layer 32 and the second optical shape layer 34 are layers substantially the same as the first optical shape layer 12 and the second optical shape layer 14 of the first embodiment described above, but the unit optical shape 321 is the first layer. The angles θ3 and θ4 formed by the first slope 321a and the second slope 321b with the plane parallel to the screen surface are different from the above-mentioned angles θ1 and θ2. Further, the angles θ3 and θ4 satisfy the relationship of θ4> θ3.

The low refractive index layer 33 is an image forming layer that forms an image of image light, diffusely reflects at least a part of the image light incident on the screen 30, and faces the observer O3 side on the back side (−Z side). Dodge. In the present embodiment, the low refractive index layer 33 is made of a resin having transparency and having a lower refractive index than the adjacent first optical shape layer 32 and second optical shape layer 34.

The low refractive index layer 33 of the present embodiment is formed on the unit optical shape 321 (on the first slope 321a and the second slope 321b), and the first low refractive index portion 331 formed on the first slope 321a. And a second low refractive index portion 332 formed on the second slope 321b.
The interface K between the second low refractive index portion 332 and the adjacent second optical shape layer 34 becomes a total reflection surface that totally reflects at least a part of the image light.

The low refractive index layer 33 is formed following the fine and irregular uneven shape formed on the first slope 321a and the second slope 321b of the unit optical shape 321 and is opposite to the unit optical shape 321 side. The surface of the surface is also formed in a state where this fine and irregular uneven shape is maintained. Therefore, the low refractive index layer 33 has fine and irregular uneven shapes on both sides thereof.
Light incident on the low refractive index layer 33 at an incident angle equal to or higher than the critical angle is diffused during total reflection due to this fine and irregular uneven shape. Further, light incident on the low refractive index layer 33 at an incident angle less than the critical angle is transmitted without being diffused.

The low refractive index layer 33 is made of a material having high light transmittance and a lower refractive index than the adjacent first optical shape layer 32 and second optical shape layer 34. As the low refractive index layer 33, for example, metal fluoride such as magnesium fluoride (MgF ₂ ) and aluminum fluoride (AlF ₃ ), silicon oxide (SiO ₂ ), and a silicon-based resin are suitable.
The low refractive index layer 33 is formed by depositing or sputtering the above-mentioned material.
The refractive index of the low refractive index layer 33 is preferably about 1.35 or more and 1.45 or less from the viewpoint of efficiently totally reflecting the image light at the interface K with the second optical shape layer 34.

The low refractive index layer 33 preferably has a thickness of 1 μm or more and 10 μm or less.
If the thickness of the low refractive index layer 33 is 1 μm or less, the total reflection of the image light at the interface K becomes insufficient, or interference occurs when the image light is totally reflected and the image is deteriorated. , Not preferable. Further, when the thickness of the low refractive index layer 33 becomes larger than 10 μm, it becomes difficult to form the low refractive index layer 33 by vapor deposition or the like, or the fine and irregular uneven shape on the surface of the unit optical shape 321 is filled. It is not preferable because it is flattened and the surface on the side opposite to the unit optical shape 321 side becomes flat.

As described above, the screen 30 of the present embodiment does not have a light diffusing layer containing a diffusing material such as particles having a diffusing action, and the image light is fine and irregular on the surface of the low refractive index layer 33. It is diffused only when it is totally reflected due to its uneven shape.

Here, the state of the image light incident on the unit optical shape 321 of the display area 30A of the present embodiment will be described.
As shown in FIG. 12, the image light L31 projected from the image source LS (see FIG. 10) and incident on the screen 10 from the image source side (+ Z side) is incident on the first slope 321a of the unit optical shape 321. At this time, since the angle of incidence of the image light L31 on the first slope 321a is less than the critical angle, many image lights L31 pass through the first low refractive index unit 331. A part of the image light L33 is reflected at the interface between the first optical shape layer 32 and the first low refractive index unit 331, but the amount of light is small and the observer O4 located on the image source side visually recognizes the image. There is no such thing.

At least a part of the image light L31 that is incident on the region B near the point v that becomes the valley bottom of the first slope 321a, passes through the first low refraction rate portion 331, and is incident on the second optical shape layer 34 is an adjacent unit. It is incident on the interface K between the second low refraction rate portion 332 and the second optical shape layer 34 formed on the second slope 321b of the optical shape 321 at an incident angle equal to or higher than the critical angle, and is totally reflected to the back surface of the screen 10. The observer O3 located in the front direction of the side (−Z side) emits an image in a visible direction (image light L32). At this time, most of the totally reflected light is diffused by the fine and irregular uneven shape of the surface of the low refractive index layer 33. As a result, the screen 30 can display an image having a good viewing angle on the observer O3 located in the front direction on the back side (−Z side).

Also in this embodiment, the video light is projected from below the screen 30, and the angle θ4 of the second slope 321b is larger than the incident angle of the video light at each point in the vertical direction of the screen 30. Light does not directly enter the second slope 321b.

Further, the external light G31 incident on the screen 10 from the back surface side (−Z side) and the external light G32 incident on the image source side (+ Z side) are both the low refractive index layer 33 and the first optical shape layer 32. Since it is incident at an angle less than the critical angle with respect to the interface of the low refractive index layer 33 and the interface between the low refractive index layer 33 and the second optical shape layer 34, the screen passes through the low refractive index layer 33 without total internal reflection at these interfaces. Head to the lower side of 10. Further, although not particularly shown, a part of the external light G31 and G32 is reflected at the interface between the screen 30 and the air, but none of them goes downward to the screen 30 and does not reach the observers O3 and O4.
Therefore, these external lights do not reach the observers O3 and O4 located in the front direction of the image source side and the back side, and the contrast decrease of the image due to the external light can be suppressed.

Further, among the external light incident on the screen surface at a small incident angle, some of the external light G33 and G34 are incident on the first low refractive index portion 331 at an angle less than the critical angle, and most of them are diffused. It passes through the display area 30A of the screen 30 without any problem. Further, some external light (not shown) incident on the screen surface at a small incident angle is incident on the second low refractive index portion 332 at an angle equal to or higher than the critical angle and is totally reflected, but is below the screen 30. Since the light is emitted to the side or the upper side, it does not prevent the observers O3 and O4 from observing the image or the transmitted image through the screen 30. Further, a part of the external light (not shown) incident on the screen surface at a small incident angle is reflected at the interface between the screen 30 and the air, but the amount of the light is small.
Therefore, when the observers O3 and O4 observe the scenery on the other side of the screen 30 through the screen 30 from the back side (-Z side) and the image source side (+ Z side), the scenery on the other side of the screen 30 is displayed. It can be observed with high transparency without blurring or bleeding white.

From the above, in the display region 30A of the screen 30 of the present embodiment, the image light is diffused only when it is totally reflected at the interface K between the low refractive index layer 33 and the second optical shape layer 34, and the low refractive index layer is formed. The light transmitted through 33 is not diffused. Therefore, according to the present embodiment, the screen 30 can display an image having a good viewing angle, brightness, and resolution on the observer O3 on the back side (−Z side), and can realize high transparency.

On the other hand, the non-display region 30B does not have the low refractive index layer 33, and the first optical shape layer 32 and the second optical shape layer 34 are formed of the same material and have the same refractive index, and are not. In the display area 30B, they are in contact with each other and are integrally laminated.
Therefore, the video light incident on the non-display region 30B and the external light incident on the non-display region 30B are the same as the video light and the external light incident on the non-display region 10B of the first embodiment described above, and a part of them is a screen. It reflects at the interface between 10 and air, most of which passes through the screen 10. Further, the external light and the image light transmitted through the non-display area 30B go downward and upward of the screen 30 and do not reach the observers O3 and O4. In the non-display area 30B, the image light is not formed and the image is not displayed.
Further, the external light incident on the non-display region 30B at a small incident angle is partially reflected at the interface between the screen 30 and the air, but most of the external light is transmitted through the non-display region 30B.

Also in this embodiment, the display region 30A has a higher light reflectance than the non-display region 30B, and among the light that is incident on the screen surface at an incident angle of 0 ° and passes through the screen 30. The proportion of light emitted at an emission angle of 0 ° is high.
Therefore, when viewed from the normal direction of the screen surface, the transmission goes from the display area 30A to the non-display area 30B and the area outside the screen adjacent to the screen 30 (in this embodiment, the area of only the support plate 50). Since the ratio of light with an emission angle of 0 ° to the light gradually increases and the light reflectance gradually decreases, the boundary between the screen 30 and the region outside the screen (support plate 50 only) becomes inconspicuous. be able to.

Therefore, according to the present embodiment, since the non-display area 30B is provided on the outer periphery of the display area 30A, the screen 30 which is a transmissive screen also has transparency, and the screen 30 and the outside of the screen ( In the present embodiment, the boundary with the region of the support plate 50) can be made inconspicuous, and a high degree of design can be achieved.
Further, according to the present embodiment, the non-display region 30B is provided on the outer periphery of the display region 30A, and the low refractive index layer 33 is not exposed on the end face of the screen 30, so that the low refractive index layer 33 and the first optical shape layer 32 are not exposed. It is possible to suppress the peeling between the layers between the low refractive index layer 33 and the second optical shape layer 34, and it is possible to improve the quality of the screen 30.
Even when silicon oxide (SiO ₂ ) or a silicon-based resin is used as the low refractive index layer 33, the peeling is likely to occur, but especially when a fluorine compound is used, the peeling is likely to occur. However, in the present embodiment, since the non-display region 30B is provided on the outer periphery of the display region 30A as described above, peeling can be effectively suppressed.

(Other embodiments of the third embodiment)
In the third embodiment, the screen 30 includes a display area 30A and a non-display area 30B, but the screen 30 is not limited to this, and is a transmissive screen as shown in the second embodiment described above. Even in a certain screen 30, a change area 30C may be provided between the display area 30A and the non-display area 30B.
For example, as shown in FIG. 9 and the like described above, the low refractive index layer 33 is discretely present in a circular shape or the like, and the region where the low refractive index layer 33 is formed toward the non-display region 30B side is formed. It may be provided so that the area occupied is small.

Further, in the change region 30C, the shape of the unit optical shape 321 may become smaller as it approaches the non-display region 30B. With such a shape, it is possible to reduce the image light toward the observer O3 side.
Further, for example, in the changing region 30C, the height of the unit optical shape 321 becomes smaller toward the non-display region 30B side, the top thereof becomes flat, and the cross-sectional shape of the unit optical shape 321 gradually becomes trapezoidal. The area of the second slope 321b that contributes to the diffused reflection of the image light may be reduced. At this time, the low refractive index layer 33 may be formed on the entire back surface side of the unit optical shape 121.

(Deformed form)
Not limited to each of the embodiments described above, various modifications and changes are possible, and these are also within the scope of the present invention.
(1) In the first embodiment and the second embodiment, the reflective layer 13 has been shown as an example of being formed along the unit optical shape 121, but the present invention is not limited to this, and the reflective layer 13 has a planar shape parallel to the screen surface. It may be a half mirror-like reflective layer in which a fine and irregular uneven shape is formed on the surface on the image source side.

(2) In the third embodiment, the screen 30 shows an example having a unit optical shape 321. However, the screen 30 is not limited to this, and for example, the image forming layer comprises a light diffusing layer containing a diffusing material that diffuses an image. It may be formed in a layered form parallel to the screen surface inside the screen.
At this time, when the changing region is provided, the light diffusion layer may be gradually or gradually thinned as it approaches the non-display region. The diffusing material used is preferably light-transmitting and preferably has a refractive index difference from the resin used as the base material containing the diffusing material.

Further, the screen may be a single light diffusing layer, and the thickness in the display region may be the largest, the thickness may be reduced toward the non-display region in the changing region, and the thickness may be the thinnest in the non-display region.
The light diffusing layer used in such a form contains a diffusing material having a large diffusing action, and it is preferable that the volume ratio of the diffusing material in the base material is small. By forming such a light diffusing layer, a part of the incident light is diffused by the diffusing material to form an image, but most of the incident light is not diffused and passes through the light diffusing layer.

(3) In the third embodiment, the low refractive index layer 33 has been described as the image forming layer, but the present invention is not limited to this, and for example, a reflective layer that reflects a part of the incident light and transmits a part of the incident light. May be used. In this case, as the reflective layer, a metal film having high light reflectivity such as silver, chromium, or aluminum, a dielectric multilayer film, or a dielectric single layer film can be used. At this time, in the changing region 30C, the thickness of the image layer may be gradually or gradually reduced toward the non-display region 30B from the display region 30A, or as in each of the above-described embodiments, the formation may be performed. The image layers may be provided so as to be discretely present in a circular shape or the like, and the area occupied by the area where the image layer is formed becomes smaller toward the non-display area 30B side. You can do it.

(4) In each embodiment, a hard coat layer for the purpose of preventing scratches may be provided on the surface of the screens 10, 20 and 30 on the image source side and the back surface side depending on the usage environment and the like. The hard coat layer is formed, for example, by applying an ultraviolet curable resin (for example, urethane acrylate or the like) having a hard coat function to the surface of the screens 10, 20, and 30 on the image source side and the back surface side. The hard coat layer is preferably formed on an exposed surface that is not covered with the support plate 50.
Further, not limited to the hard coat layer, depending on the usage environment and purpose of use of the screens 10, 20 and 30, for example, an antireflection function and ultraviolet rays may be applied to the surface of the screens 10, 20 and 30 on the image source side and the back surface side. One or a plurality of layers having necessary functions such as an absorption function, an antifouling function, and an antistatic function may be selected and provided. Further, a touch panel layer or the like may be provided on the outermost layer on the side where the observers O1 and O3 who want to provide the image are located.
In particular, in the screens 10 and 20 of the first embodiment and the second embodiment, when the antireflection layer is provided on the surface on the image source side, a part of the image light reflected by the reflection layer 13 is on the image source side. It is possible to prevent the image from being reflected at the interface with the air and emitted from the back side so that the image is displayed as if it leaked to the back side.

(5) In each embodiment, an example is shown in which the area of the support plate 50 is larger than that of the screens 10, 20, and 30, and the area outside the screen adjacent to the screens 10, 20, and 30 is only the support plate 50. Not limited to this, the screens 10, 20, 30 and the support plate 50 have the same size, and the area outside the screen adjacent to the screens 10, 20, 30 when viewed from the normal direction of the screen surface is an air layer or the like. It may be in a certain form.

(6) In each embodiment, the screens 10, 20, and 30 may be in a form that does not include the protective layer 15. At this time, for example, the screens 10, 20, and 30 may have a bonding layer in a portion corresponding to the second unit optical shape layer, which may be bonded to the support plate.

(7) In each embodiment, the screens 10, 20, and 30 may not include the base material layer 11 if the first optical shape layer 12 has sufficient thickness, rigidity, and the like. Similarly, if the second optical shape layer 14 has a sufficient thickness and composition, the protective layer 15 may not be provided.
Further, in the screens 10, 20 and 30, the base material layer 11 may be a plate-shaped member having light transmittance such as a glass plate. At this time, the portion from the first optical shape layer 12 to the protective layer 15 may be bonded to a glass plate or the like via a bonding layer or the like having light transmission (not shown). The protective layer 15 is a plate-shaped member having light transmission such as a glass plate, and the portion from the base material layer 11 to the second optical shape layer 14 is provided via a bonding layer having light transmission (not shown). May be in the form of being joined to the glass plate or the like, or the base material layer 11 and the protective layer 15 may be a glass plate or the like.

(8) In each embodiment, the image source LS has been described by giving an example of being located below the screens 10, 20, and 30, but is not limited to this, and is, for example, located above the screens 10, 20, and 30. You may. In this case, the screens 10, 20, and 30 are in the form of inverting the vertical direction (Y direction) thereof. It may also be located on the left side (or right side) of the screens 10, 20, and 30. In this case, the screens 10, 20, and 30 are rotated 90 ° to the right (or 90 ° to the left) with the point A at the center of the screen as the axis of rotation.

(9) In each embodiment, the first slopes 121a, 321a and the second slopes 121b, 321b of the unit optical shapes 121, 321 may be, for example, a combination of a curved surface and a flat surface, or may be formed as a folded surface. May be good.
Further, in each embodiment, the unit optical shapes 121 and 321 may be formed by a plurality of three or more surfaces.

(10) In the first embodiment and the second embodiment, a polarization absorbing layer that absorbs a specific polarization is provided on the back side of the reflection layer 13, and the polarization is in a polarized state different from the polarization absorbed by the polarization absorption layer. May be projected as image light. With such a form, in a transparent reflective screen, it is possible to prevent the image light transmitted through the reflective layer 13 from being reflected on an object, a person, a ceiling, or the like on the back side.

(11) In each embodiment, the screens 10, 20, and 30 show a form in which the surface on the back surface side is joined to the support plate 50, but the present invention is not limited to this, and the screens are sandwiched between two support plates 50. The screens 10, 20, and 30 may be located inside the so-called laminated glass.

(12) In each embodiment, the non-display areas 10B and 30B are provided in the entire outer peripheral area of the display areas 10A and 30A, but the present invention is not limited to this, and the non-display areas 10B and 30B are limited to only a part of the outer peripheral area of the display areas 10A and 30A. It may be formed as a form. Similarly, the change region 20C shown in the second embodiment and the change region 30C shown in another embodiment of the third embodiment may be similarly formed only on a part of the outer periphery of the display regions 10A and 30A. Alternatively, it may be arranged discretely on the outer periphery of the display areas 10A and 30A at predetermined intervals.
Further, for example, the change areas 20C and 30C are not limited to the form formed between the display areas 10A and 30A and the non-display areas 10B and 30B, and for example, the non-display areas 10B and 30C are formed on the outer periphery of the change areas 20C and 30C. It may be in the form of having a portion where 30B is not formed. For example, the change areas 20C and 30C are provided on the entire outer periphery of the display areas 10A and 30A, but the non-display areas 10B and 30B may be formed only on a part of the outer periphery of the change areas 20C and 30C. ..

(13) In the first and second embodiments, in the non-display regions 10B and 30B, as shown in FIG. 3B, the first optical shape layer 12 has an optical shape in which unit optical shapes 121 are arranged. Although the example of having the optical shape is shown, the present invention is not limited to this, and the unit optical shape 121 may not have an optical shape in which the unit optical shape 121 is arranged, and the surface on the back surface side thereof may be a flat surface. The same applies to the first optical shape layer 32 of the third embodiment.

(14) In each embodiment, the video display devices 1 and 3 show an example of being applied to a show window of a store or the like, but the present invention is not limited to this, and for example, an indoor partition or a video at an exhibition or the like is shown. It can also be applied to displays.

Although the present embodiment and the modified form can be used in combination as appropriate, detailed description thereof will be omitted. Further, the present invention is not limited to each of the embodiments described above.

1,3 Display device 10, 20, 30 Screen 11 Base material layer 12, 32 First optical shape layer 121, 321 Unit optical shape 121a, 321a First slope 121b, 321b Second slope 13 Reflective layer 14, 34 Second optical Shape layer 15 Protective layer 33 Low refractive index layer LS Image source

Claims (9)

A screen that displays an image by forming an image of the image light projected from the image source and has transparency.
A display area including an imaging layer that transmits a part of incident light and has an imaging function for displaying an image.
A non-display area provided on the outer periphery of the display area when viewed from the normal direction of the screen surface, which does not have an image layer and does not display an image, and a non-display area.
Equipped with
The image layer is provided between the two transparent layers in contact with them.
A screen featuring. In the screen according to claim 1,
A first optical shape layer having an optical shape in which unit optical shapes having a first surface and a second surface intersecting the first surface are arranged along a screen surface is provided.
The image layer is formed on at least a part of the first surface of the unit optical shape, and has an irregular uneven shape on the surface thereof.
Provided with a second optical shape layer formed so as to fill the valley portion of the unit optical shape on which the image forming layer is formed.
A screen featuring. In the screen according to claim 1 or 2.
The image layer is made of metal or a dielectric.
A screen featuring. In the screen according to claim 1 or 2.
The image layer has transparency and has a lower refractive index than the two adjacent transparent layers.
A screen featuring. In the screen according to any one of claims 1 to 4.
When viewed from the normal direction of the screen surface, the region adjacent to the non-display region of the display region is a changing region in which the imaging action of the image light gradually decreases toward the non-display region. ,
A screen featuring. In the screen according to claim 5,
In the change region, the thickness of the image layer becomes thinner toward the non-display region.
A screen featuring. In the screen according to claim 5,
The area occupied by the region having an imaging effect becomes smaller as the changing region moves toward the non-display region.
A screen featuring. In the screen according to claim 5,
In the change area, the image layer is formed discretely and the area occupied by the area where the image layer is formed becomes smaller toward the non-display area.
A screen featuring. The screen according to any one of claims 1 to 8.
An image source that projects image light on the screen and
A video display device equipped with.

Images