JP6717051B2 - Screen, video display - Google Patents

Description

The present invention relates to a screen and a video display device including the screen.

Conventionally, various screens have been developed as a screen that reflects or transmits image light projected from an image source and displays the screen (for example, see Patent Document 1). Among them, a transparent screen can be fixed by attaching it to a highly translucent member such as a window glass, and reflecting or transmitting projected image light to display an image, and Since the scenery on the other side of the screen can be seen through when not in use, such as when it is not projected by light, demand is increasing due to its high designability.

JP-A-9-114003

However, when such a screen having transparency is provided with a diffusion layer containing diffusing particles and the like, the scenery on the other side of the screen is observed whitish and faint, which leads to a reduction in designability. Improvement was a challenge. Further, it is always required to reduce the thickness and display good images with high contrast on various screens.
Further, in the case of a screen having transparency, when the image light is projected obliquely to the screen, a part of the image light is emitted upward in the direction opposite to the image source side in the thickness direction of the screen. There is. When such image light (light passing through) is generated especially at the upper portion of the screen of the screen, there is a problem that the image is reflected on the ceiling or the like, and the design of the image display device is deteriorated.
In particular, with a reflective screen that is transparent and that reflects and displays image light, such light leakage causes the image to be reflected on the ceiling above the back side of the screen where it should not be displayed. Therefore, it is not preferable.

The above-mentioned Patent Document 1 proposes a projection screen that can be used for both the transmissive type and the reflective type, and can transmit light from the back side. However, Patent Document 1 does not disclose any measures for improving transparency and measures for reflecting an image on the ceiling.

An object of the present invention is to provide a screen having high transparency and capable of reducing the reflection of an image on the ceiling, and an image display device including the screen.

The present invention solves the above problems by the following means. It should be noted that, for ease of understanding, reference numerals corresponding to the embodiments of the present invention will be given and described, but the present invention is not limited thereto.
A first aspect of the present invention is a screen that reflects image light projected from an image source, displays an image toward an observer, and has transparency, and a surface on the back side in the thickness direction of the screen. A plurality of unit optical shapes ( 121 ) each having a first surface ( 121a ) on which image light is incident and a second surface ( 121b ) facing the first surface ( 121a ) are arrayed to form a light-transmitting optical shape. A layer ( 12 ) and a reflective layer ( 13 ) formed on at least a part of the first surface of the unit optical shape and having a function of reflecting at least a part of incident light and transmitting other light. A second optical shape layer (14) which is light-transmissive and is laminated so as to fill a valley between the unit optical shapes on the back side of the reflective layer in the thickness direction of the screen, Which does not include a light diffusing layer containing diffusing particles having a function of diffusing light, the unit optical shape has a fine and irregular uneven shape on its surface, at least the reflective layer The surface on the unit optical shape side has a concavo-convex shape corresponding to the concavo-convex shape, and a through-light suppression layer ( 15 ) that absorbs or diffuses at least a part of the image light transmitted through the reflective layer is formed on the screen thickness. Bei example on the rear side of the reflecting layer in the direction, the refractive index of the second optical shape layer, and the refractive index of the optical shape layer is equivalent, or have a small refractive index difference enough to be regarded as equivalent The light leakage suppression layer is a layer having a function of absorbing at least a part of the image light transmitted through the reflection layer, and includes a light transmission portion (153) that transmits light and a light absorption portion (153) that absorbs light. 154), and in the cross section parallel to the thickness direction of the screen, the light transmitting portions and the light absorbing portions are alternately arranged along the screen surface, and the cross sectional shape of the light absorbing portion in the cross section is rectangular. Alternatively , the screen ( 10 ) has a wedge shape and is a reflective screen that reflects projected image light to display an image .
A second aspect of the present invention is a screen that reflects image light projected from an image source and displays an image toward an observer side, and that is transparent, and has a rear surface in the thickness direction of the screen. A plurality of unit optical shapes (321) having a first surface (321a) on which the image light is incident and a second surface (321b) facing the first surface (321a) are arranged and formed, and an optical shape having optical transparency is formed. A layer (32) and a reflective layer (33) formed on at least a part of the first surface of the unit optical shape and having a function of reflecting at least a part of incident light and transmitting other light. A second optical shape layer (34) that is light-transmissive and is laminated so as to fill the valleys between the unit optical shapes on the back side of the reflective layer in the thickness direction of the screen, Which does not include a light diffusing layer containing diffusing particles having a function of diffusing light, the unit optical shape has a fine and irregular uneven shape on its surface, at least the reflective layer The surface on the unit optical shape side has a concave-convex shape corresponding to the concave-convex shape, and includes a light-through suppressing layer (15) that absorbs or diffuses at least a part of the image light transmitted through the reflective layer, and the thickness of the screen. Is provided on the back side of the reflective layer in the direction, and the refractive index of the second optical shape layer is equal to or smaller than the refractive index of the optical shape layer. The light escape suppression layer is a layer having a function of absorbing at least a part of the image light transmitted through the reflection layer, and has a light transmitting portion (153) that transmits light and a light absorbing portion (154) that absorbs light. ) And in a cross section parallel to the thickness direction of the screen, the light transmitting portions and the light absorbing portions are alternately arranged along the screen surface, and the cross sectional shape of the light absorbing portion in the cross section is rectangular or A screen (30) having a wedge shape, which is a transmissive screen that reflects projected image light and transmits the screen to display an image.
A third aspect of the present invention is a screen that reflects image light projected from an image source and displays an image toward an observer side, and that has transparency, and has a rear surface in a thickness direction of the screen. A plurality of unit optical shapes (121) having a first surface (121a) on which the image light is incident and a second surface (121b) facing the first surface (121a) are arranged and formed, and an optical shape having a light transmitting property is formed. A layer (12) and a reflective layer (13) formed on at least a part of the first surface of the unit optical shape and having a function of reflecting at least a part of incident light and transmitting other light. A second optical shape layer (14) which is light-transmissive and is laminated so as to fill a valley between the unit optical shapes on the back side of the reflective layer in the thickness direction of the screen, Which does not include a light diffusing layer containing diffusing particles having a function of diffusing light, the unit optical shape has a fine and irregular uneven shape on its surface, at least the reflective layer The surface on the unit optical shape side has a concave-convex shape corresponding to the concave-convex shape, and has a through-light suppression layer (25) that absorbs or diffuses at least a part of the image light transmitted through the reflective layer, the thickness of the screen. Is provided on the back side of the reflective layer in the direction, and the refractive index of the second optical shape layer is equal to or smaller than the refractive index of the optical shape layer. The light escape suppression layer is a layer having a function of diffusing at least a part of the image light transmitted through the reflection layer, and is incident on the light escape suppression layer within a first incident angle range (R1). The light incident at an angle is diffused, the light incident at an incident angle outside the first incident angle range is transmitted, the first incident angle range is larger than 0°, and the projected image light is reflected to form an image. A screen (20) characterized by being a reflective screen for displaying.
A fourth invention is, in the screen of the first invention or the second invention , when the refractive index of the light transmitting portion (153) is N1 and the refractive index of the light absorbing portion (154) is N2, N2. The screen (10, 30) is characterized by satisfying a relationship of ≧N1.
5th invention is the screen of 4th invention , Comprising: The said light transmission part (153) and the said light absorption part (154) are extended in the screen left-right direction in the use state of this screen, and are arranged in the screen up-down direction. The screen (10, 30) is characterized in that
A sixth invention is the screen (20) according to the third invention , characterized in that the first incident angle range (R1) is 25 to 75°.
7th invention is the screen in any one of 1st invention to 6th invention , Comprising: The said optical shape layer (12, 32) WHEREIN: The said unit optical shape (121, 321) is multiply arranged in concentric form. A screen (10, 20, 30) characterized by having a circular Fresnel lens shape.
An eighth invention is a video display device comprising the screen (10, 20, 30) according to any one of the first invention to the seventh invention, and a video source (LS) for projecting video light on the screen. It is (1).

According to the present invention, it is possible to provide a screen having high transparency and capable of reducing the reflection of an image on the ceiling, and an image display device including the screen.

It is a figure which shows the video display apparatus 1 of 1st Embodiment. It is a figure which shows 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 explaining the light leakage suppression layer 15 of 1st Embodiment. It is a figure which shows the mode of the image light and external light on the screen 10 of 1st Embodiment. It is a figure which shows another form of the through-light suppression layer 15 of 1st Embodiment. It is a figure which shows the layer structure of the screen 20 of 2nd Embodiment. It is a figure explaining the light leakage suppression layer 25 of 2nd Embodiment. It is a figure which shows 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. It should be noted that each of the following drawings including FIG. 1 is a schematic view, and the size and shape of each portion are exaggerated as appropriate for easy understanding.
In the present specification, numerical values such as dimensions of respective members and material names described in the present specification are merely examples of the embodiment, and the present invention is not limited thereto and may be appropriately selected and used.
In the present specification, terms that specify a shape or a geometric condition, for example, terms such as parallel and orthogonal, have a strict meaning, and have a similar optical function, and can be regarded as parallel and orthogonal. It also includes the state with the error of.

In this specification, the terms plate, sheet, film, etc. are used, but as a general usage, these are used in the order of thickness, plate, sheet, film, in order. In the specification, it is used in a similar manner. However, since there is no technical meaning in such proper use, these words can be appropriately replaced.
In the present specification, the sheet surface refers to the surface of each sheet in the plane direction of the sheet when viewed as the entire sheet. The same applies to the plate surface and the film surface.

(First embodiment)
FIG. 1 is a diagram showing a video display device 1 of the first embodiment. 1A is a perspective view of the video display device 1, and FIG. 1B is a view of the video display device 1 as viewed from the side.
The image display device 1 has a screen 10, an image source LS, and the like. 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 an image on the screen. Details of the screen 10 will be described later.
In the present embodiment, as an example, the image display device 1 is applied to a partition using a transparent plate for indoor use, and an example in which the screen 10 is fixed to the transparent plate will be described. As such a transparent plate, a highly transparent plate-shaped member such as glass or resin is used.

Here, in order to facilitate understanding, in each of the following drawings including FIG. 1, an XYZ orthogonal coordinate system is appropriately provided and shown. In this coordinate system, the horizontal direction (horizontal direction) of the screen 10 is the X direction, the vertical direction (vertical direction) 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.
In addition, the direction toward the right side in the horizontal direction when viewed from the observer O1 located in the front direction on the image source side of the screen 10 is +X direction, the direction toward the upper side in the vertical direction is +Y direction, and the rear side (back side) in the thickness direction. ) Is the +Z direction.
Further, in the following description, the screen up-down direction, the screen left-right direction, and the thickness direction, unless otherwise specified, the screen up-down direction (vertical direction), the screen left-right direction (horizontal direction) in the usage state of the screen 10. It is a thickness direction (depth direction), and is assumed to be parallel to the Y direction, the X direction, and the Z direction, respectively.

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 is the center of the screen 10 in the left-right direction when the screen (display area) of the screen 10 is viewed from the front direction (the normal direction of the screen surface) when the image display device 1 is in use. Thus, the screen 10 is located vertically below the screen.
The image source LS can project the image light L obliquely from the position where the distance from the surface of the screen 10 in the depth direction (Z direction) is much closer than that of a general-purpose projector located in the screen front direction of the conventional screen. .. Therefore, as compared with the conventional general-purpose projector, the image source LS has a short projection distance to the screen 10, a large incident angle at which the projected image light L is incident on the screen 10, and a change amount of the incident angle (from the minimum value). The amount of change up to the maximum value) is also large.

The screen 10 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 can display the image on the observer O1. It is a reflective screen having transparency so that the scenery on the other side of 10 can be observed.
The screen (display area) of the screen 10 has a substantially rectangular shape in which the long side direction is the horizontal direction of the screen when viewed from the observer O1 side in the use state. Further, the screen 10 has a screen size of about 40 to 100 inches diagonally and a screen aspect ratio of 16:9.
Not limited to this, the screen 10 may have, for example, a shape viewed from the observer O1 side, or the screen size may be 40 inches or less. The size and shape can be appropriately selected according to the above.

Generally, the screen 10 is a laminated body of thin layers made of resin, etc., and often does not have sufficient rigidity to maintain flatness by itself. Therefore, as shown in FIG. 1, the screen 10 of the present embodiment is integrally bonded (or partially fixed) to the support plate 50 through the bonding layer 51 having a light-transmitting property on the back surface side, and the flatness of the screen is obtained. Is maintained.
The support plate 50 is a flat plate-shaped member having optical transparency and high rigidity, and a plate-shaped member made of resin such as acrylic resin or PC (polycarbonate) resin or glass can be used. The support plate 50 of this embodiment is a glass transparent plate for an indoor partition.
The screen 10 is not limited to this, and the screen 10 may have a configuration in which the four sides thereof are supported by a frame member or the like (not shown) and the planarity thereof is maintained.

FIG. 2 is a diagram showing a layer structure of the screen 10 of the first embodiment. In FIG. 2, a point A (see FIG. 1), which is the center of the screen of the screen 10 (the geometric center of the screen), passes through, is parallel to the vertical direction of the screen (Y direction), and is orthogonal to the screen surface (in the Z direction). A part of the cross section (parallel) is enlarged and shown. Note that, in FIG. 2, only the screen 10 is shown, and the support plate 50 and the like are omitted.
FIG. 3 is a diagram illustrating the first optical shape layer 12 of the first embodiment. FIG. 3A is a view of the first optical shape layer 12 viewed from the back surface side (−Z side), and the reflective layer 13 and the like are omitted for easy understanding. FIG. 3B is a view for explaining the unit optical shape 121 of the first optical shape layer 12, and shows an enlarged part of the cross section of the screen 10 shown in FIG. 2. In FIG. 3B, the base material layer 11 and the light leakage suppression layer 15 are omitted for easy understanding.
As shown in FIG. 2, the screen 10 includes a base material layer 11, a first optical shape layer 12, a reflective layer 13, and a second optical shape in this order from the image source side (+Z side) in the thickness direction (Z direction). The layer 14 and the light leakage suppression layer 15 are provided.

The base material layer 11 is a light-transmissive sheet-like member, 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 base material (base) for forming the first optical shape layer 12.
The base material layer 11 is made of, 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, or a TAC (triester). Acetyl cellulose) resin or the like.
The thickness of the base material layer 11 may be appropriately set depending on the screen size of the screen 10.

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 side (−Z side) of the first optical shape layer 12.
As shown in FIG. 3A, the unit optical shape 121 is a partial shape of a perfect circle (arc shape), and is concentric with the point C located outside the screen (display area) of the screen 10 as the center. There are multiple arrangements. That is, the first optical shape layer 12 has a circular Fresnel lens shape having a so-called offset structure with the point C as the center (Fresnel center) on the back side thereof.
In the present embodiment, as shown in FIG. 3A, when the first optical shape layer 12 is viewed from the rear side in the normal direction of the screen surface, the point C is at the center in the left-right direction of the screen and outside the screen. It is located below, and points C and A are located on the same straight line.

As shown in FIG. 2 and FIG. 3B, the unit optical shape 121 has a cross-sectional shape parallel to a direction (Z direction) orthogonal to the screen surface and in a cross section parallel to the arrangement direction of the unit optical shapes 121. , Has a substantially triangular shape.
The unit optical shape 121 is convex on the back side (−Z side), and has a first slope (lens surface) 121a on which the image light is incident and a second slope (non-lens surface) 121b facing the first slope. ing. In one unit optical shape 121, the first slope 121a is located above the second slope 121b (+Y side) with the vertex t interposed therebetween.

The angle formed by the first inclined surface 121a and the surface parallel to the screen surface is θ1. The angle formed by the second inclined surface 121b and the surface parallel to the screen surface is θ2. The angles θ1 and θ2 satisfy the relationship of θ2>θ1.
The first inclined surface 121a and the second inclined surface 121b of the unit optical shape 121 have fine irregular irregular shapes. The fine concavo-convex shape is formed by arranging convex shapes and concave shapes irregularly in a two-dimensional direction, and the convex shapes and concave shapes have irregular sizes, shapes, heights, and the like.

The arrangement pitch of the unit optical shapes 121 is P1, and the height of the unit optical shapes 121 (the dimension from the vertex t in the thickness direction to the point v that is the valley bottom between the unit optical shapes 121) is h1.
To facilitate understanding, FIGS. 2 and 3B show an example in which the arrangement pitch P1 of the unit optical shapes 121 and the angles θ1 and θ2 are constant in the arrangement direction of the unit optical shapes 121. However, in the unit optical shape 121 of the present embodiment, the arrangement pitch P1 is actually constant, but the angle θ1 gradually increases as the distance from the point C, which is the Fresnel center, in the arrangement direction of the unit optical shape 121. ..
The angles θ1 and θ2, the array pitch P1, and the like are the projection angle of the image light from the image source LS (the incident angle of the image light to the screen 10), the size of the pixels of the image source LS, and the screen 10. It may be appropriately set according to the screen size, the refractive index of each layer, and the like. For example, the arrangement pitch P1 and the angle θ1 may be changed along the arrangement direction of the unit optical shapes 121.

In the present embodiment, the example in which the circular Fresnel lens shape is formed on the back surface of the first optical shape layer 12 is shown, but the present invention is not limited to this, and the back surface side of the first optical shape layer 12 is not limited to this. A linear Fresnel lens shape may be formed on the surface in which the unit optical shapes 121 are arranged in the screen vertical direction (Y direction) with the screen horizontal direction (X direction) as the longitudinal direction. Further, a plurality of columnar unit prisms may be provided in the vertical direction (Y direction) of the screen with the horizontal direction of the screen (X direction) as the longitudinal direction.

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

The reflective layer 13 is formed on the unit optical shape 121 (on the first slope 121a and the second slope 121b). The reflective layer 13 is a semi-transmissive reflective layer that reflects a part of incident light and transmits the other, that is, a so-called half mirror.
As described above, the fine sloped shapes are formed on the first slope 121a and the second slope 121b (the surface of the unit optical shape 121), and the reflective layer 13 is formed following these fine sloped shapes. The film is also formed on the surface opposite to the unit optical shape 121 side while maintaining the fine and irregular uneven shape. Therefore, the surface on the image source side (the surface on the first optical shape layer 12 side) and the surface on the rear surface side (the surface on the second optical shape layer 14 side) of the reflective layer 13 have fine and irregular uneven shapes. It has a matte surface (rough surface).
The reflective layer 13 has a function of diffusing and reflecting a part of the incident light by the fine unevenness of the reflecting surface and transmitting other light that is not reflected without diffusing.

Further, the reflectance and the transmittance of the reflective layer 13 can be appropriately set according to the desired optical performance. From the viewpoint of satisfactorily reflecting the image light and satisfactorily transmitting light other than the image light (for example, light from the outside world such as sunlight), the reflectance and the transmittance of the reflective layer 13 are 30 to 30%. It is desirable that the reflectance is about 80% and the reflectance is about 5 to 60%.

The reflective layer 13 is formed of a metal having a high light reflectivity, such as aluminum, silver, nickel or the like, and has a thickness of about several tens of liters. The reflective layer 13 of this embodiment is formed by depositing aluminum.
The reflective layer 13 is not limited to this, and may be formed by sputtering a metal having high light reflectivity as described above, or may be formed by depositing a dielectric multilayer film or by sputtering. May be.
The reflective layer 13 of the present embodiment is formed by vapor-depositing aluminum, and has a half mirror shape in which the reflectance of only the reflective layer 13 is about 15% and the transmittance is about 50%.

The second optical shape layer 14 is a layer having optical transparency provided on the back surface side (−Z side) of the first optical shape layer 12.
The second optical shape layer 14 is filled so as to fill the valleys between the unit optical shapes 121, and the back surface side (−Z side) of the first optical shape layer 12 is flattened. The image source side (+Z side) surface of the second optical shape layer 14 is formed by arranging a plurality of substantially reverse shapes of the unit optical shapes 121 of the first optical shape layer 12.
By providing such a second optical shape layer 14, the reflection layer 13 can be protected. Further, by providing such a second optical shape layer 14, it becomes easy to stack the light escape suppression layer 15 and the like on the back side of the screen 10, and also it becomes easy to bond the screen 10 to the support plate 50 and the like. ..

The refractive index of the second optical shape layer 14 is preferably substantially the same as that of the first optical shape layer 12 (a state in which the refractive index difference is small enough to be considered equivalent), and is preferably the same. Further, the second optical shape layer 14 may be formed by using the same resin as the above-mentioned first optical shape layer 12 or may be formed by using a different resin.
The second optical shape layer 14 of the present embodiment is formed of the same ultraviolet curable resin as the first optical shape layer 12.

FIG. 4 is a diagram illustrating the light leakage suppression layer 15 of the first embodiment. In FIG. 4A, of the cross section of the screen 10 shown in FIG. 2, only the light leakage suppression layer 15 is shown in an enlarged manner. In FIG. 4B, a part of the light escape suppression layer 15 viewed from the front side on the back side (−Z side) is shown in an enlarged manner.
The light escape suppression layer 15 is a layer provided on the back surface side (−Z side) of the second optical shape layer 14. As shown in FIGS. 2 and 4, the light leakage suppressing layer 15 has a base material portion 151 and a light control portion 152.

The base material portion 151 is a member serving as a base (base material) of the light leakage suppression layer 15. The base material portion 151 is a resin-made sheet-shaped member having light transmittance.
The base material portion 151 is formed of, for example, a polyester resin such as PET having high light transmittance, an acrylic resin, a styrene resin, an acrylic/styrene resin, a PC resin, an alicyclic polyolefin resin, or a TAC resin.

The light control unit 152 has a light transmitting unit 153 and a light absorbing unit 154, and has a so-called louver shape in which these are alternately arranged.
As shown in FIG. 4B, the light transmitting portion 153 has a substantially columnar shape whose longitudinal direction is the left-right direction of the screen (X direction), and the back surface (−Z side) of the base material part 151 has a screen. A plurality of them are arranged in the vertical direction of the screen along the surface.
A cross-sectional shape of the light transmitting portion 153, which is parallel to the arrangement direction (Y direction) and parallel to the thickness direction (Z direction) of the screen 10, is a substantially trapezoidal shape as shown in FIG. The dimension W2 on the image source side (+Z side) is larger than the dimension W1 on the back surface side (−Z side), and the image source side end is continuous in the XY directions.
The light transmitting portion 153 of the present embodiment has an isosceles trapezoidal cross-sectional shape, and is symmetrical in the vertical direction (Y direction) of the screen, which is the arrangement direction.

The light transmitting portion 153 has a light transmitting property and is formed by molding an ultraviolet curable resin such as urethane acrylate by an ultraviolet molding method. However, not limited to this, the light transmitting portion 153 may be formed of another ionizing radiation curable resin such as an electron beam curable resin.
The light transmitting portion 153 is not limited to the ultraviolet curable resin as described above, but may be formed by hot melt extrusion molding using a thermoplastic resin such as PET resin. At this time, if the continuous portion of the light transmitting portion 153 on the image source side has sufficient thickness, rigidity, etc., the base material portion 151 may not be provided.

The light absorbing portion 154 is a portion having a function of absorbing light, and is formed in a valley-shaped portion between adjacent light transmitting portions 153, as shown in FIG.
As shown in FIG. 4B, the light absorbing parts 154 extend in the left-right direction of the screen (X direction), and are alternately arranged in the light-transmitting parts 153 along the screen surface in the up-down direction of the screen (Y direction). ing.
As shown in FIG. 4B, the back surface of the escaped light suppression layer 15 is formed by the back surface of the light transmitting portion 153 and the back surface of the light absorbing portion 154.

The light absorbing portion 154 has a wedge-shaped cross section in a cross section parallel to the array direction (Y direction) and parallel to the thickness direction (Z direction) of the screen 10. Here, the wedge shape means a shape in which one end is wide and becomes gradually narrower toward the other end, and includes a triangular shape and a trapezoidal shape.
As shown in FIG. 4A, the light absorbing portion 154 of the present embodiment is an isosceles trapezoid in which the dimension W4 on the image source side (+Z side) is smaller than the dimension W3 on the back side (−Z side), The shape is symmetrical in the vertical direction (Y direction) of the screen, which is the arrangement direction.

When the refractive index of the light transmitting portion 153 is N1 and the refractive index of the light absorbing portion 154 is N2, it is preferable that N1≦N2 is satisfied from the viewpoint of absorbing the image light transmitted through the reflective layer 13. When the difference in the refractive index between the two is sufficiently small, the refractive index N2 of the light absorbing portion 154 may be smaller than the refractive index N1 of the light transmitting portion 153.
In the present embodiment, the refractive index N2 of the light absorbing portion 154 is larger than the refractive index N1 of the light transmitting portion 153, and N2≧N1 is satisfied.

The light absorption portion 154 is formed by wiping (squeezing) and filling a valley portion between the light transmission portions 153 with a resin containing a light absorbing material having a function of absorbing light, and curing the resin. ..
The resin serving as the base material of the light absorbing portion 154 is preferably an ionizing radiation curable resin such as an ultraviolet curable resin such as urethane acrylate or epoxy acrylate, or an electron beam curable resin. As described above, when the refractive index of the light absorbing portion 154 is set to be higher than the refractive index of the light transmitting portion 153, the resin serving as the base material of the light absorbing portion 154 is higher than the resin forming the light transmitting portion 153. Also, it is preferable that the refractive index is large.

The light absorbing material used for the light absorbing portion 154 is a particulate member having a function of absorbing light in the visible light region, and examples thereof include metal salts such as carbon black, graphite, black iron oxide, pigments and dyes, Resin particles colored with a pigment or a dye are suitable. When resin particles colored with a pigment or a dye are used, those resin particles made of acrylic resin, PC resin, PE resin, PS resin, MBS resin, MS resin, or the like should be used. Can be used.

As shown in FIG. 4A, the arrangement pitch of the light transmitting portions 153 (light absorbing portions 154) is P2, and the thickness of the light control portion 152 is D1. Further, in the arrangement direction of the light transmitting portions 153, the dimension of the light transmitting portions 153 on the image source side (+Z side) is W2, the dimension of the rear surface side (−Z side) is W1, and the dimension of the light absorbing portion 154 on the image source side is. W4, the size of the back side is W3.
The dimension of the light absorbing portion 154 in the thickness direction (Z direction) of the screen 10 is h2, and the angle formed by the interface between the light transmitting portion 153 and the light absorbing portion 154 with the thickness direction of the screen 10 is θ3. is there.
The angle θ3, the dimension h2, the pitch P2, and the like can be appropriately set according to the incident angle of the image light, the refractive index of the light transmitting portion 153, and the like.

In the present embodiment, the screen 10 has a mode in which the light leakage suppression layer 15 is located on the most back side of the screen, and the support plate 50 is integrated with the rear surface of the light leakage suppression layer 15 via the bonding layer 51. It has a form of being laminated. However, the present invention is not limited to this, and the screen 10 may further include a protective layer (not shown) that protects the rear surface of the screen 10 on the rear surface side of the light leakage suppression layer 15.

As described above, the screen 10 of the present embodiment does not include the light diffusing layer containing the diffusing material such as diffusing particles having the action of diffusing light, and the diffusing action is caused by the surface of the reflective layer 13. Only the fine concavo-convex shape of.

FIG. 5 is a diagram showing a state of image light and external light on the screen 10 of the first embodiment. In FIG. 5, a part of a cross section similar to the cross section shown in FIG. 2 (a cross section parallel to the arrangement direction of the unit optical shapes 121 (Y direction) and the thickness direction of the screen 10 (Z direction)) is enlarged. .. Further, in FIG. 5, in order to facilitate understanding, an interface between the base material layer 11 and the first optical shape layer 12, an interface between the first optical shape layer 12 and the reflection layer 13, a reflection layer 13 and the second optical shape layer 13 are shown. It is shown that there is no difference in refractive index between the interface with the shaping layer 14, the interface between the second optical shaping layer 14 and the base material portion 151, and the interface between the base material portion 151 and the light transmitting portion 153.
Of the image light L1 projected from the image source LS located below the screen 10 and incident on the screen 10, a part of the image light L2 is incident on the first inclined surface 121a of the unit optical shape 121, and the reflection layer 13 is formed. Is diffusely reflected by and emitted to the observer O1 side.

Of the image light incident on the first inclined surface 121a, the other image light L4 that has not been reflected by the reflective layer 13 passes through the reflective layer 13 and most of it is absorbed by the light absorbing portion 154 of the light leakage suppressing layer 15. It Therefore, the amount of image light that passes through the reflective layer 13 and is emitted upward from the back side of the screen 10 is significantly reduced.
Therefore, it is possible to significantly suppress the reflection of the image that is generated when the image light transmitted through the reflective layer 13 and emitted to the back side (−Z side) of the screen 10 reaches the ceiling or the like near the screen 10 on the back side. ..

Further, a part of the image light L3 projected from the image source LS is reflected on the surface of the screen 10 and goes upward to the image source side (+Z side) of the screen 10, so that the image of the observer O1. Does not hinder the visibility of the.
In the present embodiment, the image light L1 is projected from below the screen 10, and the angle θ2 (see FIG. 2) is larger than the incident angle of the image light at each point of the screen 10 in the vertical direction of the screen. The light does not directly enter the second slope 121b, and the second slope 121b has almost no influence on the reflection of the image light.

Next, light (hereinafter, referred to as “external light”) from the outside world such as sunlight other than the image light incident on the screen 10 from the back side (−Z side) or the image source side (+Z side) will be described.
As shown in FIG. 5, a part of the external light G2 that is incident on the screen 10 from above the image source side is reflected by the surface of the screen 10 and travels toward the lower side of the screen to the observer O1. Not reach. Further, a part of the external light G3 of the external light G1 is reflected by the reflective layer 13, a part of the external light G3 is emitted to the lower side of the screen 10, and a part of the external light G3 is entirely on the image source side (+Z side) surface of the screen 10. It reflects and travels downward in the screen 10 and is attenuated.
In addition, external light G4 that is incident on the screen 10 from above the image source side and that is transmitted through the reflective layer 13 is incident on the light absorbing portion 154 of the escaped light suppressing layer 15 and most of it is efficiently absorbed, and is emitted from the back side. The amount of light emitted is significantly reduced.

Of the external light G5 that enters the screen 10 from above the back side, a part of the external light G6 is reflected on the surface of the screen 10, goes to the lower side of the screen, and does not reach the observer O2. Also, of the external light G5, most of the external light G7 that has entered the screen 10 is incident on the light absorbing portion 154 and is absorbed.
In addition, external light that has entered the screen 10 from above the back surface side and has passed through the escaped light suppression layer 15 is reflected by the reflective layer 13 as external light G8 and enters the light absorbing portion 154 to be absorbed. Although not shown, the light may pass through the reflective layer 13 and be emitted downward to the image source side of the screen 10, or may be totally reflected by the surface of the image source side, and may be attenuated toward the lower inside of the screen.
Therefore, the external light that enters the screen 10 from above the rear surface side is efficiently absorbed by the light absorbing portion 154 of the escaped light suppressing layer 15, and the amount of light emitted from the image source side is significantly reduced.
From the above, it is possible to remarkably reduce that the external light that enters the screen 10 from the image source side or the back side reaches the observer O1 and the contrast of the image is lowered.

Further, external light G9, G10 having a small incident angle on the screen 10 passes through the reflective layer 13 and is emitted to the back side and the image source side, respectively. Since the screen 10 does not contain a diffusing material or the like containing diffusing particles, the external light G9, G10 that passes through the screen 10 is not diffused.
Therefore, when the observers O1 and O2 observe the scenery on the other side of the screen 10 through the screen 10, the scenery on the other side of the screen 10 does not become blurred or bleeds white and has high transparency. Can be observed.

In a conventional semi-transmissive reflective screen having a light diffusing layer containing diffusing particles having a function of diffusing light, the image light is diffused twice before and after being reflected by the reflecting layer, resulting in a good viewing angle. However, there is a problem that the resolution of the image is reduced. In addition, since the external light is also diffused by the diffusing particles, the scenery on the other side of the screen is obscured or bleeding white is observed.

However, the screen 10 of the present embodiment does not have a diffusing effect except that the surface of the reflective layer 13 has fine irregular irregular shapes, and the image light is diffused only when reflected. Further, in the screen 10 of the present embodiment, only the light reflected by the reflective layer 13 is diffused, and the light transmitted through the reflective layer 13 is not diffused. Therefore, the screen 10 of the present embodiment can display an image having a good viewing angle and resolution, and the view on the other side of the screen 10 is not visually blurred or blurred to the observer O1. Therefore, high transparency can be realized.
Further, in the screen 10 of the present embodiment, the observer O1 can partially view the scenery on the other side (back side, -Z side) of the screen 10 even when the image light is projected on the screen 10. It is possible. Further, on the screen 10, the observer O2 located on the back side can satisfactorily view the view on the image source side (+Z side) through the screen 10 with high transparency regardless of whether or not the image light is projected. can do.

Further, if the screen 10 does not include the light escape suppression layer 15, part of the image light transmitted through the reflective layer 13 is emitted above the screen 10 from the back side (−Z side) of the screen 10. At this time, when the image light (light passing through) that has passed through the reflective layer 13 is emitted from the area corresponding to the upper screen portion on the back side of the screen 10, such light passing reaches the ceiling on the back side of the screen 10. Then, there is a problem that the image is reflected and the designability of the image display device is deteriorated. Such image reflection on the ceiling is particularly likely to occur when the screen 10 is a large screen.

However, in the screen 10 of the present embodiment, the image light (light passing) that has passed through the reflective layer 13 can be efficiently absorbed by the light absorbing portion 154 of the light passing suppressing layer 15, and such image reflection on the ceiling is prevented. Can be greatly improved.
In addition, in the screen 10 of the present embodiment, the escaped light suppression layer 15 transmits light that enters the screen 10 at a small incident angle such as an incident angle of 0° (for example, external light G9 and G10 shown in FIG. 5). When the viewers O1 and O2 visually recognize the scenery or the like on the other side of the screen through the screen 10, sufficient transparency can be maintained.
Further, in the screen 10 of the present embodiment, unnecessary external light such as sunlight and illumination light incident from above the back side of the screen 10 is absorbed, so that the contrast of the image can be improved and a good image can be displayed.

(Another form of the light escape suppression layer 15 of the first embodiment)
FIG. 6 is a diagram showing another form of the light leakage suppression layer 15 of the first embodiment. FIG. 6 shows a cross section corresponding to the cross section shown in FIG. 4 described above in another form of the light leakage suppression layer 15.
As shown in FIG. 6A, the light absorption portion 154 of the light leakage suppression layer 15 has a rectangular cross-sectional shape in a cross section parallel to the arrangement direction (Y direction) and the thickness direction (Z direction) of the screen 10. Alternatively, as shown in FIG. 6B, the shape may be triangular. In addition, the cross-sectional shape of the light absorbing portion 154 may be not only a strict rectangular shape and a wedge shape, but also a substantially rectangular shape or a substantially wedge shape having a slight difference that can be regarded as the shape.
Further, as shown in FIG. 6C, the light absorption portion 154 of the light leakage suppression layer 15 has a cross-sectional shape in a cross section parallel to the array direction (Y direction) and the thickness direction (Z direction) of the screen 10. The size W4 on the image source side (+Z side) may be larger than the size W3 on the back side (−Z side), or when the cross-sectional shape of the light absorbing section 154 is triangular, the back side. It is also possible to adopt a form in which the apex is located at. In this case, the base material portion 151 is located on the back side of the light control portion 152.

Further, as shown in FIG. 6C, the light leakage suppression layer 15 is in a form in which the base material portion 151 is located on the back side of the light control section 152, and the support plate 50 and the like are provided on the back side of the screen 10. In the case where it does not exist, a function such as a hard coat function, an antireflection function, an antistatic function, an antifouling function, or an ultraviolet absorbing function may be appropriately selected and added to the base material portion 151.
The light absorbing portion 154 may have a cross-sectional shape other than an isosceles trapezoidal shape such as a trapezoidal shape, an isosceles triangular shape, an isosceles triangular shape, a parallelogram shape, and a pentagonal shape. At least one of the interfaces with the light transmissive portion 153 may have a bent surface shape or a part thereof may be formed by a curved surface.

(Second embodiment)
FIG. 7 is a diagram showing a layer structure of the screen 20 of the second embodiment. FIG. 7 shows a cross section of the screen 20 corresponding to the cross section of the screen 10 shown in FIG.
The screen 20 according to the second embodiment is different from the screen 20 according to the first embodiment except that the screen 20 according to the second embodiment includes a light leakage suppression layer 25 having a characteristic different from that of the light leakage suppression layer 15 according to the first embodiment. It has the same form as 10. Therefore, the portions having the same functions as those of the above-described first embodiment are designated by the same reference numerals or the same reference numerals at the end, and redundant description will be appropriately omitted.
The screen 20 of the present embodiment includes a base material layer 11, a first optical shape layer 12, a reflection layer 13, a second optical shape layer 14, and a light leakage suppression layer 25. The screen 20 is applicable to the video display device 1 shown in the first embodiment.

FIG. 8 is a diagram illustrating the light leakage suppression layer 25 of the second embodiment. In order to facilitate understanding, FIG. 8 shows only the light leakage suppression layer 25 in the cross section of the screen 20 shown in FIG. 7, and the straight line H is orthogonal to the surface of the light leakage suppression layer 25 on the image source side. It is a straight line.
The light escape suppression layer 25 is a layer provided on the back surface side of the second optical shape layer 14. The light escape suppression layer 25 diffuses the light incident on the light escape suppression layer 25 from the image source side (+Z side) at an incident angle within the first incident angle range R1 and emits the light to the back surface side (−Z side). However, it has a function of transmitting light incident at an incident angle within the second incident angle range R2 other than the first incident angle range R1 to the back side without diffusing.
The surface on the image source side (+Z side) and the surface on the back surface side (−Z side) of the light escape suppression layer 25 are parallel to the screen surface (YX surface).

The first incident angle range R1 includes an angle range in which the image light projected from the image source LS and incident on the screen 20 and transmitted through the screen is mainly incident on the escaped light suppression layer 25.
The first incident angle range R1 is about 25 to 75°. The light escape suppression layer 25 diffuses the light incident at an incident angle of 25° or more and 75° or less from the lower side in the vertical direction of the screen to an arbitrary point on the surface on the image source side, and diffuses the light to the rear side (-Z Side).

The second incident angle range R2 is an angle other than the first incident angle range R1. As shown in FIG. 8, the light escape suppression layer 25 has an incident angle of 0° or more and 90° or less on the upper side in the vertical direction of the screen, and an incident angle on the lower side of the vertical direction of the screen with respect to an arbitrary point on the surface on the image source side. Light incident on the lower side in the vertical direction of the screen at 0° or more and less than 25° and an incident angle of more than 75° and 90° or less is transmitted without being diffused and is emitted from the rear surface.

In the present embodiment, the first incident angle range R1 is 25 to 55°, and the light escape suppression layer 25 is incident on the arbitrary point on the image source side (+Z side) from the lower side in the vertical direction of the screen. The incident light is diffused at 25° or more and 55° or less. In addition, the light escape suppression layer 25 transmits light that is incident at an incident angle in the second incident angle range R2 other than the first incident angle range R1.
Further, the light leakage suppression layer 25 of the present embodiment transmits the light incident from the back surface side (−Z side) to the image source side.
As such a light leakage suppressing layer 25, a visibility control film formed by laminating a plurality of transparent resin layers having different refractive indexes in a predetermined direction with a predetermined thickness (for example, Lumisty manufactured by Sumitomo Chemical Co., Ltd. ) Is preferred.

In the present embodiment, since the light leakage suppressing layer 25 as described above is provided, a part of the image light obliquely projected from the lower side of the image source side passes through the reflective layer 13 toward the rear surface side and escapes. When the light is incident on the light suppressing layer 25, the image light can be diffused and emitted.
Therefore, according to the present embodiment, it is possible to suppress the reflection of the image on the ceiling and maintain the transparency.

The first incident angle range R1 and the second incident angle range R2 are used environment, desired optical performance of the image display device 1, projection angle of image light from the image source LS (incident angle of image light to the screen 20). It can be appropriately set according to the above.
For example, the first incident angle range R1 is set to the upper and lower sides of the screen in the vertical direction of 25 to 55°, and the light escape suppression layer 25 is a straight line H orthogonal to the surface of the light escape suppression layer 25 on the image source side. With respect to the vertical direction of the screen, the light incident at an incident angle of 25 to 55° on the upper side and 25 to 55° on the lower side is diffused, and the light incident at an incident angle within a predetermined incident angle range from the back side is also diffused. It may be in the form.

(Third Embodiment)
FIG. 9 is a diagram showing a layer structure of the screen 30 of the third embodiment. FIG. 9 shows a cross section of the screen 30 corresponding to the cross section of the screen 10 shown in FIG.
The screen 30 of the third embodiment is the same as the screen 10 of the first embodiment except that a low refractive index layer 33 is provided instead of the reflective layer 13 shown in the first embodiment. It is a form. Therefore, the portions having the same functions as those of the above-described first embodiment are designated by the same reference numerals or the same reference numerals at the end, and redundant description will be appropriately omitted.
The screen 30 of the present embodiment 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 light leakage suppression layer 15. The screen 30 can be applied to the video display device 1 shown in the first embodiment, instead of the screen 10.

In the screen 10 of the above-described first embodiment, at least a part of the light projected from the image source side (+Z side) is reflected toward the image source side by the reflection layer 13 in the thickness direction of the screen, and is positioned on the image source side. The screen was for displaying an image to the observer O1.
On the other hand, in the screen 30 of the present embodiment, at least a part of the light projected from the image source side is reflected to the back side (−Z side) by the low refractive index layer 33, and the viewer positioned on the back side. It is a screen for displaying an image on O2.

The first optical shape layer 32 and the second optical shape layer 34 have the same shapes as the first optical shape layer 12 and the second optical shape layer 14 of the above-described first embodiment, but the materials thereof are It is different from the first optical shape layer 12 and the second optical shape layer 14 of the first embodiment.
The first optical shape layer 32 and the second optical shape layer 34 have a high light transmittance and a UV curable resin having a higher refractive index than a general UV curable resin (for example, epoxy acrylate-based UV curable resin or , A UV-curable resin such as a urethane-based resin having a high refractive index added with a metal oxide, and a UV-curable resin having a high refractive index added with titanium oxide (TiO ₂ ). There is.
The first optical shape layer 32 and the second optical shape layer 34 may be formed of another ionizing radiation curable resin such as an electron beam curable resin.
The first optical shape layer 32 and the second optical shape layer 34 preferably have a refractive index of about 1.56 to 1.7.

The low-refractive index layer 33 is a layer that is light-transmissive and has a lower refractive index than the adjacent first optical shape layer 32 and second optical shape layer 34.
The low refractive index layer 33 is formed on the unit optical shape 321 (on the first inclined surface 321a and the second inclined surface 321b), and includes the first low refractive index portion 331 formed on the first inclined surface 321a and the second low refractive index portion 331. The second low refractive index portion 332 is formed on the inclined surface 321b. The interface K between the second low refractive index portion 332 and the 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 so as to follow the fine and irregular asperity shape formed on the unit optical shape 321, and has fine and irregular asperity shapes on both surfaces thereof. The low-refractive index layer 33 has such a thickness that the image light can be fully totally reflected at the interface K and no interference occurs when the image light is totally reflected.

Light incident on the low-refractive index layer 33 at an incident angle equal to or greater than the critical angle is diffused at the time of total reflection due to the 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 has a high light transmittance and a material having a lower refractive index than the adjacent first optical shape layer 32 and second optical shape layer 34 (for example, a metal fluoride such as magnesium fluoride or aluminum fluoride). , Silicon oxide, silicon-based resin) by vapor deposition or sputtering.
The refractive index of the low-refractive index layer 33 is about 1.35 to 1.45, so that the image light can be efficiently totally reflected at the interface K between the second optical shape layer 14 and the second low-refractive index portion 332. It is preferable from the viewpoint.

As shown in FIG. 9, the image light La projected from the image source LS and incident on the screen 30 from the light incident side (−Z side) is incident on the first slope 321 a of the unit optical shape 321.
At this time, since the incident angle of the image light La on the first slope 321a is less than the critical angle, a large amount of the image light La passes through the first low refractive index portion 331. Although part of the image light Lc is reflected, the amount of light is small, and the observer O1 located on the image source side does not visually recognize the image.
Further, at least a part of the image light La that is incident on the region B near the point v that is the valley bottom of the first slope 321a, is transmitted through the first low refractive index portion 331 and is incident on the second optical shape layer 34, is 2 At the interface K between the low refractive index portion 332 and the second optical shape layer 34, the light is incident on the interface K at an incident angle equal to or greater than the critical angle and is totally reflected, and an image is displayed by an observer O2 located in the front direction on the back side of the screen 30. Emit in a visible direction. At this time, most of the totally reflected light is diffused due to the fine and irregular irregularities on the surface of the low refractive index layer 33 (see the image light Lb in FIG. 9). Thereby, the observer O2 can visually recognize an image having a good viewing angle.

In order that the image light La that has entered the region B and transmitted through the first low refractive index portion 331 is reflected at the interface K and is emitted to the observer O2 side, the second inclined surface 321b (second low refractive index) is used. The angle Φ formed by the portion 332) with respect to the direction orthogonal to the screen surface is preferably 0°<φ<2×(θ1), and φ is substantially equal to θ1 (having an error that can be regarded as equal). (State) is more preferable, and φ is more preferably equal to θ1.
The angle θ2 gradually decreases and the angle φ gradually increases as the distance from the point C increases along the arrangement direction of the unit optical shapes 321.

When the angle φ is 0°, the incident angle of the image light incident on the interface K is less than the critical angle and the image light is not totally reflected on the interface K, so that the image light cannot be directed to the back side.
Further, when the angle φ is 2×(θ1) or more, the image light totally reflected at the interface K2 goes upward to the back side of the screen 10 and reaches the observer O2 located in the front direction on the back side of the screen 10. Absent. Therefore, the angle φ is preferably in the above range.
Further, as the angle φ approaches the angle θ1, the apex angle θ3 of the unit optical shape 121 approaches 90°, and when the angle φ equals the angle θ1, the apex angle θ3 equals 90°. When the apex angle θ3=90°, the region B is a region having the dimension S1=Psin(θ1)tan(θ1) from the point v toward the apex t along the first slope 321a.

Part of the image light Ld passes through the first low refractive index portion 331 and travels upward in the screen toward the rear side without being totally reflected at the interface K. Then, such image light Ld is emitted from the screen 30 to the upper rear side when the light leakage suppression layer 15 is not provided, and causes the image to be reflected on the ceiling. This reflection of the image on the ceiling is uncomfortable for the observer O2 located on the back side, and also hinders good visual recognition of the image.
However, according to the present embodiment, the screen 30 can effectively suppress the reflection of the image on the ceiling by absorbing the image light Ld by the light absorbing portion 154 of the light leakage suppression layer 15, and thus the design is improved. In addition to improving the performance, the effect that the observer can visually recognize the image comfortably is exhibited.
Further, according to the present embodiment, since the low refractive index layer 33 has a light transmitting property, it is possible to display an image while having a high transparency.

(Variation)
The present invention is not limited to the embodiments described above, and various modifications and changes can be made, which are also within the scope of the present invention.
(1) In each embodiment, a hard coat layer for the purpose of preventing scratches may be provided on the surface of the screen 10, 20, 30 on the image source side (+Z side). The hard coat layer is formed, for example, by applying an ultraviolet curable resin (for example, urethane acrylate) having a hard coat function to the surface of the screen 10, 20, 30 on the image source side.
In addition to the hard coat layer, the surface of the screen 10, 20, 30 on the image source side may have, for example, an antireflection function, an ultraviolet absorption function, or the like depending on the use environment or purpose of use of the screen 10, 20, 30. One or more layers having appropriate functions such as 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 image source side of the base material layer 11.

In particular, when an antireflection layer is provided on the surface of the screen 10, 20, 30 on the image source side, the image light reflected by the reflective layer 13 is reflected at the interface with the air on the image source side, and the rear side It is possible to prevent the image from being emitted from and displayed on the back side as if it were leaked.
It should be noted that not only the image source side (+Z side) surface of the screens 10, 20, 30 but also a back side (−Z side) surface may be provided with a layer having a hard coat function or an antireflection function.

(2) In each of the embodiments, the screens 10, 20, 30 are configured such that the light leakage suppressing layers 15, 25 located on the back surface side (−Z side) are integrally bonded to the support plate 50 via the bonding layer 51. However, the present invention is not limited to this, and the base layer 11 located on the image source side (+Z side) may be joined to the support plate 50 via the joining layer 51.
In this way, when the back side of the screens 10, 20, 30 is exposed, a hard coat function, an antireflection function, an ultraviolet absorbing function, an antifouling function, and a charging function are provided on the back side of the light leakage suppressing layers 15, 25. One or a plurality of layers having a necessary function such as a prevention function may be provided.

(3) In each of the embodiments, the screens 10, 20, 30 may not have the base material layer 11 when the first optical shape layer 12 has a sufficient thickness, rigidity and the like.
Further, in the screens 10, 20 and 30, the base material layer 11 may be a plate-like member having a light-transmitting property such as a glass plate. At this time, the first optical shape layer 12 and the like may be bonded to the glass plate and the like via the adhesive layer and the like.

(4) In the first embodiment and the second embodiment, the fine irregularities on the surface of the reflection layer 13 (the surface of the unit optical shape 121) have irregular sizes, shapes, arrangements, and the like. However, any of the size, shape, and arrangement may have regularity.
The same applies to the uneven shape of the surface of the low refractive index layer 33 of the third embodiment.

(5) In each of the embodiments, the image source LS has been described by taking an example in which it is located at the center of the screens 10, 20, and 30 in the left-right direction of the screen and below the outside of the screen. A configuration may be employed in which the screen light is arranged obliquely below the screens 10, 20, 30 and the image light is projected from the oblique light in the left-right direction of the screen with respect to the screens 10, 20, 30.
In this case, the arrangement direction of the unit optical shapes 121 and 321 is tilted according to the position of the image source LS. With such a form, the position of the image source LS and the like can be freely set.

(6) In each of the embodiments, the unit optical shapes 121 and 321 have been described by way of example in which the first slopes 121a and 321a and the second slopes 121b and 321b are formed by flat surfaces. The shape may be a combination of flat surfaces or a bent surface.
Moreover, the unit optical shapes 121 and 321 may be polygonal shapes formed by three or more surfaces.
The example in which the reflective layer 13 is formed on the first inclined surface 121a and the second inclined surface 121b of the unit optical shape 121 is shown, but the present invention is not limited to this, and is formed on at least a part of the first inclined surface 121a, for example. It may be in the form.
Further, although the first slopes 121a, 321a and the second slopes 121b, 321b have shown an example in which fine and irregular uneven shapes are formed, the present invention is not limited to this, and only the first slopes 121a, 321a are fine and It is also possible to adopt a form in which irregular irregular shapes are formed.

(7) In each embodiment, the image source LS may project, for example, image light having a P-wave polarization component.
At this time, the position and angle of the image source LS are set so that the image light is projected onto the screens 10, 20, 30 at the incident angle φ. This incident angle φ is (φb-10), where φb(°) is the incident angle (Brewster angle) at which the reflectance of the image light (P wave) projected on the screens 10, 20, 30 becomes zero. It is set in the range of ° to 85°. For example, when the incident angle φb at which the reflectance of the image light projected on the screen 10 is zero is 60°, the incident angle φ of the image light is set in the range of 50 to 85°.

In this way, by using the image source LS that projects the image light having the polarization component of the P wave, even when the incident angle φ on the screens 10, 20, 30 is large, the surface of the screens 10, 20, 30 is Specular reflection can be suppressed, and the degree of freedom in designing the projection system such as the installation position of the image source LS can be increased. Further, by using such an image source LS, it is possible to reduce reflection of image light on the surface of the screen when entering the screen 10, 20, 30 and improve brightness and sharpness of the image. ..
The angle φb (Brewster angle) differs depending on the material of the surface of the screen 10 onto which the image light is projected.
In the case of such a form, as the base material layer 11, a sheet-shaped member made of TAC is suitable.

(8) In each of the embodiments, the example in which the image display device 1 is arranged in an indoor partition has been shown, but the present invention is not limited to this. Can also be applied. Also, the screens 10, 20, 30 may be attached to the windshield, and the image display device 1 may be applied to a head-up display (HUD: HEAD-Up Display) of an automobile, or to a vehicle other than an automobile. May be.

It should be noted that the present embodiment and the modified embodiments may be appropriately combined and used, but detailed description thereof will be omitted. Further, the present invention is not limited to the embodiments described above.

1 Video 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 Light-through suppression layer 151 Base material 152 Light control part 153 Light transmission part 154 Light absorption part 25 Light-through suppression layer 33 Low refractive index layer

Claims (8)

A screen that reflects the image light projected from the image source and displays the image toward the viewer side, and that has transparency.
On the rear surface of the screen in the thickness direction, a plurality of unit optical shapes each having a first surface on which image light is incident and a second surface opposite thereto are arranged and formed, and an optical element having optical transparency is formed. A shape layer,
A reflection layer formed on at least a part of the first surface of the unit optical shape and having a function of reflecting at least a part of incident light and transmitting other light;
A second optical shape layer that is light-transmissive on the back side of the reflective layer in the thickness direction of the screen and is laminated so as to fill the valleys between the unit optical shapes;
Equipped with
Does not have a light diffusion layer containing diffusion particles having the function of diffusing light,
The unit optical shape has a fine and irregular uneven shape on its surface,
At least the surface of the reflection layer on the unit optical shape side has an uneven shape corresponding to the uneven shape,
The missing light suppression layer that absorbs or diffuses at least a part of the image light transmitted through the reflective layer, Bei example on the rear side of the reflecting layer in the thickness direction of the screen,
The refractive index of the second optical shape layer is the same as the refractive index of the optical shape layer, or has a small refractive index difference that can be regarded as equivalent.
The light escape suppression layer,
A layer having a function of absorbing at least a part of image light transmitted through the reflective layer,
A light transmitting portion that transmits light and a light absorbing portion that absorbs light, in a cross section parallel to the thickness direction of the screen, the light transmitting portions and the light absorbing portions are arranged alternately along the screen surface, The cross-sectional shape of the light absorbing portion in the cross section is a rectangular shape or a wedge shape,
It is a reflective screen that reflects the projected image light and displays the image.
Screen characterized by. A screen that reflects the image light projected from the image source and displays the image toward the viewer side, and that has transparency.
On the rear surface of the screen in the thickness direction, a plurality of unit optical shapes each having a first surface on which image light is incident and a second surface opposite thereto are arranged and formed, and an optical element having optical transparency is formed. A shape layer,
A reflection layer formed on at least a part of the first surface of the unit optical shape and having a function of reflecting at least a part of incident light and transmitting other light;
A second optical shape layer that is light-transmissive on the back side of the reflective layer in the thickness direction of the screen and is laminated so as to fill the valleys between the unit optical shapes;
Equipped with
Does not have a light diffusion layer containing diffusion particles having the function of diffusing light,
The unit optical shape has a fine and irregular uneven shape on its surface,
At least the surface of the reflection layer on the unit optical shape side has an uneven shape corresponding to the uneven shape,
A through-light suppressing layer that absorbs or diffuses at least a part of the image light transmitted through the reflective layer is provided on the back side of the reflective layer in the thickness direction of the screen,
The refractive index of the second optical shape layer is the same as the refractive index of the optical shape layer, or has a small refractive index difference that can be regarded as equivalent.
The light escape suppression layer,
A layer having a function of absorbing at least a part of image light transmitted through the reflective layer,
A light transmitting portion that transmits light and a light absorbing portion that absorbs light, in a cross section parallel to the thickness direction of the screen, the light transmitting portions and the light absorbing portions are arranged alternately along the screen surface, The cross-sectional shape of the light absorbing portion in the cross section is a rectangular shape or a wedge shape,
A transmissive screen that reflects projected image light and transmits the screen to display an image.
Screen characterized by. A screen that reflects the image light projected from the image source and displays the image toward the viewer side, and that has transparency.
On the rear surface of the screen in the thickness direction, a plurality of unit optical shapes each having a first surface on which image light is incident and a second surface opposite thereto are arranged and formed, and an optical element having optical transparency is formed. A shape layer,
A reflection layer formed on at least a part of the first surface of the unit optical shape and having a function of reflecting at least a part of incident light and transmitting other light;
A second optical shape layer that is light-transmissive on the back side of the reflective layer in the thickness direction of the screen and is laminated so as to fill the valleys between the unit optical shapes;
Equipped with
Does not have a light diffusion layer containing diffusion particles having the function of diffusing light,
The unit optical shape has a fine and irregular uneven shape on its surface,
At least the surface of the reflection layer on the unit optical shape side has an uneven shape corresponding to the uneven shape,
A through-light suppressing layer that absorbs or diffuses at least a part of the image light transmitted through the reflective layer is provided on the back side of the reflective layer in the thickness direction of the screen,
The refractive index of the second optical shape layer is the same as the refractive index of the optical shape layer, or has a small refractive index difference that can be regarded as equivalent.
The light escape suppression layer,
A layer having a function of diffusing at least a part of image light transmitted through the reflection layer,
The incident light suppressing layer diffuses light incident at an incident angle within the first incident angle range and transmits light incident at an incident angle outside the first incident angle range,
The first incident angle range is greater than 0°,
It is a reflective screen that reflects the projected image light and displays the image.
Screen characterized by. The screen according to claim 1 or 2 ,
When the refractive index of the light transmitting portion is N1 and the refractive index of the light absorbing portion is N2, the relationship of N2≧N1 is satisfied,
Screen characterized by. The screen according to claim 4 ,
The light transmitting portion and the light absorbing portion extend in the horizontal direction of the screen when the screen is in use, and are arranged in the vertical direction of the screen.
Screen characterized by. The screen according to claim 3 ,
The first incident angle range is 25 to 75°,
Screen characterized by. The screen according to any one of claims 1 to 6 ,
The optical shape layer has a circular Fresnel lens shape in which the plurality of unit optical shapes are concentrically arranged.
Screen characterized by. A screen according to any one of claims 1 to 7 ,
An image source for projecting image light on the screen,
A video display device.

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