JP2016109778A - Light-transmissive transparent screen, and system and method for displaying image - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-transmissive transparent screen which allows for seeing a scene on the other side of a screen that appears transparent to viewers and viewing images displayed on the screen transparent to viewers, and which minimizes transmission of infrared rays therethrough, and to provide a system and method for displaying images.SOLUTION: A light-transmissive transparent screen 1 includes a light scattering layer 34 and infrared shielding layer 36, and preferably features a total light transmittance of no less than 1%, haze of 4-50%, and total light reflectance at a wavelength of 800 nm that is greater than that at a wavelength of 589 nm.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a transmissive transparent screen that displays image light projected from a projector as an image to an observer on the opposite side of the projector, and an image display system and an image display method using the same.

Showcases for products, etc .; display cases for works of art, etc .; windows for buildings, showrooms, vehicles, etc .; glass doors;
Can see through the transparent member as seen from the observer side, and when transmitting information such as product descriptions, various equipment states, destination guidance, and transmission items to the observer On the other hand, when displaying operation screens of various devices, or when making it impossible to see through the scene behind the transparent member to the observer for privacy protection, security, etc., images projected from the projector An image display transparent member (so-called transparent screen) that displays light as a visual image to an observer.

  The transparent screen has a reflective transparent screen that displays the image light projected from the projector as an image to an observer on the same side as the projector; and the image light projected from the projector is opposite to the projector There is a transmissive transparent screen that is visibly displayed as an image to an observer on the side.

  As the transmissive transparent screen, for example, a transparent resin 132 and a light scattering material 133 (for example, hollow beads) are provided between a first transparent substrate 110 and a second transparent substrate 120 as shown in FIG. There has been proposed a transmissive transparent screen 101 having a light scattering layer 134 containing (see Patent Document 1).

  In the transmissive transparent screen 101, the image light L projected from the projector 200 and incident from the surface (first surface A) on the first transparent base material 110 side is scattered by the light scattering layer 134. The image is displayed so as to be visible to the observer X on the opposite side of the projector 200 as an image.

  In addition, in the transmissive transparent screen 101, the light of the scene on the first surface A side is incident on the transmissive transparent screen 101 from the first surface A, and then partially scattered in the light scattering layer 134, and the remaining light. Is transparent. As a result, when the image light L is not projected from the projector 200 onto the transmissive transparent screen 101, the observer X on the second surface B side can see through the scene on the first surface A side. Similarly, after the light of the scene on the second surface B side is incident on the transmissive transparent screen 101 from the second surface B, a part of the light is scattered in the light scattering layer 134 and the rest is transmitted. Thereby, when the image light L is not projected onto the transmissive transparent screen 101 from the projector 200, the observer on the first surface A side can see through the scene on the second surface B side.

  Incidentally, in the transmissive transparent screen 101, as shown in FIG. 6, the sunlight L1 incident on the transmissive transparent screen 101 is partially scattered in the light scattering layer 134, but the rest is transmitted. Therefore, the transmissive transparent screen 101 is used as, for example, a shop show window, and the image light L is projected from the projector 200 in the store onto the transmissive transparent screen 101 to an observer X (passerby etc.) outside the store. On the other hand, when the video is displayed, there is a problem that sunlight L1 passes through the transmissive transparent screen 101 and enters the store, and the store becomes hot.

Japanese Patent No. 4847329

  The present invention is a transmissive transparent screen capable of seeing through a scene beyond the transparent screen as viewed from the observer, visually recognizing an image displayed on the transparent screen as viewed from the observer, and suppressing infrared transmission, and A video display system and a video display method using the same are provided.

The present invention has the following configuration.
[1] A transmissive transparent screen having a light scattering layer and an infrared shielding layer.
[2] Transmission of [1], wherein the total light transmittance is 1% or more, the haze is 4 to 50%, and the total light reflectance at a wavelength of 800 nm is higher than the total light reflectance at a wavelength of 589 nm. Type transparent screen.
[3] The transmissive transparent screen according to [1] or [2], wherein the light scattering layer includes a transparent resin and a light scattering material.
[4] The transmissive transparent screen according to any one of [1] to [3], wherein the infrared shielding layer is at least one selected from the group consisting of a metal thin film, a semiconductor thin film, and a dielectric thin film.
[5] A video display system comprising: the transmissive transparent screen according to any one of [1] to [4]; and a projector installed at a position where video light can be projected onto the transmissive transparent screen.
[6] A video display method in which video light is projected from a projector onto the transmissive transparent screen of any one of [1] to [4] to display a video.

The transmission type transparent screen of the present invention can see through the transparent screen as seen from the observer, can see the image displayed on the transparent screen as seen from the observer, and can suppress infrared transmission. Is.
According to the video display system and the video display method of the present invention, it is possible to see through the transparent screen as viewed from the observer, to visually recognize the video displayed on the transparent screen as viewed from the observer, and to the transmission type. Infrared transmission through the transparent screen is suppressed.

It is a schematic block diagram which shows an example of the video display system of this invention, and a layer block diagram which shows an example of the transmission type transparent screen of this invention. It is a layer block diagram which shows the other example of the transmission type transparent screen of this invention. It is a layer block diagram which shows the other example of the transmission type transparent screen of this invention. It is a layer block diagram which shows the other example of the transmission type transparent screen of this invention. 3 is a transmission spectrum of a transmission type transparent screen of Example 1 and Example 2. It is the schematic block diagram which shows an example of the conventional video display system, and the layer block diagram which shows an example of the conventional transmission type transparent screen.

The following definitions of terms apply throughout this specification and the claims.
The “first surface” means the outermost surface of the transmissive transparent screen and the surface on the side where image light is projected from the projector.
The “second surface” means the outermost surface of the transmissive transparent screen and the surface opposite to the first surface.
“The scene on the first surface side (second surface side)” means the other side of the transmissive transparent screen as viewed from the observer on the second surface side (first surface side) of the transmissive transparent screen. It means an image (a main object (a product, a work of art, a person, etc.) and its background, a landscape, etc.) that is visible to the side. The scene does not include an image in which the image light projected from the projector is imaged and displayed on the transmissive transparent screen.
The “sheet” may be a sheet or a continuous belt.
“Arithmetic average roughness (Ra)” is an arithmetic average roughness measured based on JIS B 0601: 2013 (ISO 4287: 1997, Amd. 1: 2009). The reference length lr (cut-off value λc) for the roughness curve was 0.8 mm.
“Haze” is the front of the transmitted light that is incident from the first surface side (or the second surface side) of the transmissive transparent screen and is transmitted to the second surface side (or the first surface side). By scattering, it means the percentage of transmitted light that deviates 0.044 rad (2.5 °) or more from incident light. That is, it is a normal haze measured by the method described in JIS K 7136: 2000 (ISO 14782: 1999).
The “total light transmittance” is the second surface side (or first surface side) with respect to incident light incident at an incident angle of 0 ° from the first surface side (or second surface side) of the transmissive transparent screen. ) Means the ratio (percentage) of the total transmitted light transmitted. That is, it is a normal total light transmittance measured by the method described in JIS K 7361: 1997 (ISO 13468-1: 1996).
The “total light reflectance” is the first surface side (or second surface side) with respect to incident light incident at an incident angle of 0 ° from the first surface side (or second surface side) of the transmissive transparent screen. ) Is the ratio (percentage) of the total reflected light reflected. When measuring the total light reflectance, a transmissive transparent screen from the second surface side (or first surface side) opposite to the first surface side (or second surface side) to be measured. The opposite surface is covered with a black curtain or the like so that light does not enter the.
The haze, total light transmittance, and refractive index are values measured at room temperature using d-line (wavelength 589 nm) of a sodium lamp. The total light reflectance is a value measured at room temperature using d-line (wavelength 589 nm) of a sodium lamp or infrared light having a wavelength of 800 nm.

<Transparent transparent screen>
The transmission-type transparent screen of the present invention has a first surface and a second surface opposite to the first surface, and either one or both of a scene on the first surface side and a scene on the second surface side. Transmission-type transparency that allows the viewer on the side opposite to the surface to be seen through and displays the image light projected from the first side as a video to the viewer on the second side. A screen having a light scattering layer and an infrared shielding layer.

FIG. 1 is a layer configuration diagram showing an example of a transmissive transparent screen of the present invention.
In the transmissive transparent screen 1, a light scattering sheet 30 is disposed between a first transparent substrate 10 and a second transparent substrate 20.
The first transparent substrate 10 and the light scattering sheet 30 are bonded by the adhesive layer 12, and the second transparent substrate 20 and the light scattering sheet 30 are bonded by the adhesive layer 22.

(Transparent substrate)
Examples of the material of the first transparent substrate 10 and the second transparent substrate 20 (hereinafter collectively referred to as a transparent substrate) include glass and transparent resin. The material of each transparent substrate may be the same or different.

  Examples of the glass constituting the transparent substrate include soda lime glass, alkali-free glass, borosilicate glass, and aluminosilicate glass. The transparent substrate made of glass may be subjected to chemical strengthening, physical strengthening, hard coating or the like in order to improve durability.

  As the transparent resin constituting the transparent substrate, polycarbonate, polyester (polyethylene terephthalate, polyethylene naphthalate, etc.), triacetyl cellulose, cycloolefin polymer, polymethyl methacrylate, ethylene-tetrafluoroethylene copolymer (hereinafter referred to as ETFE) In view of weather resistance and transparency, polycarbonate, polyester, and cycloolefin polymer are preferable.

As the transparent substrate, those having no birefringence are preferable.
The thickness of a transparent base material should just be the thickness by which durability as a base material is maintained. The thickness of the transparent substrate may be, for example, 0.01 mm or more, 0.05 mm or more, and 0.1 mm or more. Further, the thickness of the transparent substrate may be, for example, 10 mm or less, 5 mm or less, 0.5 mm or less, 0.3 mm or less, and 0.15 mm or less. It's okay.

(Adhesive layer)
Examples of materials for the adhesive layer 12 and the adhesive layer 22 (hereinafter collectively referred to as an adhesive layer) include ethylene-vinyl acetate copolymer, polyvinyl butyral, pressure-sensitive adhesive (acrylic pressure-sensitive adhesive, etc.), and photocurable resin composition. , Thermosetting resin compositions, thermoplastic resin compositions, and the like. The material of each adhesive layer may be the same or different.

  Examples of the thermoplastic resin contained in the thermoplastic resin composition include plasticized polyvinyl acetal, plasticized polyvinyl chloride, saturated polyester, plasticized saturated polyester, polyurethane, plasticized polyurethane, ethylene-vinyl acetate copolymer, ethylene -Ethyl acrylate copolymer etc. are mentioned.

  The thickness of the adhesive layer is not particularly limited as long as the function as the adhesive layer is maintained. For example, 0.01 to 1.5 mm is preferable, and 0.05 to 1 mm is more preferable.

(Light scattering sheet)
The light scattering sheet 30 includes a first transparent film 31; a second transparent film 35; a transparent resin 32 and a light scattering material provided between the first transparent film 31 and the second transparent film 35. A light-scattering layer 34 including 33; an infrared ray shielding composed of at least one selected from the group consisting of a metal thin film, a semiconductor thin film, and a dielectric thin film provided between the light scattering layer 34 and the second transparent film 35; Layer 36.

(Transparent film)
The first transparent film 31 and the second transparent film 35 (hereinafter collectively referred to as a transparent film) may be a transparent resin film or a thin glass film. The material of each transparent film may be the same or different.

  Examples of the transparent resin constituting the transparent resin film include polycarbonate, polyester (polyethylene terephthalate, polyethylene naphthalate, etc.), triacetyl cellulose, cycloolefin polymer, polymethyl methacrylate, ETFE and the like.

  The thickness of the transparent film is preferably such that a roll-to-roll process can be applied, for example, 0.01 to 0.5 mm is preferable, 0.05 to 0.3 mm is more preferable, and 0.2 mm or less is more preferable.

(Light scattering layer)
The light scattering layer 34 includes, for example, a transparent resin 32, a light scattering material 33, and, if necessary, a light absorbing material.

  The transparent resin 32 is preferably a cured product of a photocurable resin (such as an acrylic resin or an epoxy resin), a cured product of a thermosetting resin, or a thermoplastic resin. The yellow index of the transparent resin is preferably 10 or less, and more preferably 5 or less from the viewpoint of maintaining transparency so that the function as a window in the transmissive transparent screen 1 is not impaired.

  Examples of the light scattering material 33 include high refractive index materials such as titanium oxide (refractive index: 2.5 to 2.7), zirconium oxide (refractive index: 2.4), and aluminum oxide (refractive index: 1.76). Fine particles: Fine particles of a low refractive index material such as porous silica (refractive index: 1.3 or less), hollow silica (refractive index: 1.3 or less), etc .; Resin materials having low refractive index and low compatibility with the transparent resin 32; Examples thereof include a crystallized resin material of 1 μm or less.

0.005-5 volume% is preferable and, as for the content rate of the light-scattering material 33, 0.01-1 volume% is more preferable.
When the light scattering material 33 is fine particles, the average particle diameter of the fine particles is preferably 0.02 to 1 μm, and more preferably 0.1 to 0.8 μm. When the average particle diameter of the fine particles is approximately the same as or slightly smaller than the wavelength of the scattered light, the probability of being scattered forward increases, and the function of scattering incident light without refracting becomes stronger. As a result, the distortion of the scene seen beyond the transmissive transparent screen 1 when viewed from the observer side is suppressed and the amount of light is not changed abruptly, thereby improving the transparency of the scene.

When the light scattering layer 34 includes a light absorbing material, a part of light propagating as unnecessary stray light in the transmissive transparent screen 1 can be absorbed, and scattered light is reduced. Therefore, it is possible to suppress the phenomenon that the transmissive transparent screen 1 appears cloudy. Further, the contrast of the scene seen from the other side of the transmissive transparent screen 1 when viewed from the observer side is improved, and the transparency of the scene is also improved. In particular, when an environment of 100 lux or more is present in the observer's line of sight due to external light, the above-described effect is easily obtained.
Examples of the light absorbing material include carbon black and titanium black. When it is desired to improve the infrared reflection performance, carbon black that absorbs less in the infrared region is preferable, and when it is desired to improve the infrared absorption performance, titanium black is preferable.
The content ratio of the light absorbing material is preferably 0.005 to 5% by volume, and more preferably 0.05 to 3% by volume.

The thickness of the light scattering layer 34 is preferably 1 to 200 μm. When the thickness of the light scattering layer 34 is 1 μm or more, the light scattering effect is sufficiently exhibited. When the thickness of the light scattering layer 34 is 200 μm or less, the light scattering layer 34 is easily formed by a roll-to-roll process.
In the light scattering layer 34, the light scattering material 33 may be uniformly dispersed throughout the light scattering layer 34 or may be localized near the surface of the light scattering layer 34.

(Infrared shielding layer)
The infrared shielding layer 36 only needs to transmit at least part of visible light and reflect or absorb at least part of infrared light among the light incident on the infrared shielding layer 36.
Examples of the infrared shielding layer 36 include a metal film, a semiconductor film, a dielectric single layer film, a dielectric multilayer film, and a multilayer film obtained by combining these.

Examples of the metal constituting the metal film and the semiconductor film include aluminum, silver, nickel, chromium, tungsten, silicon, and the like. Aluminum, silver, or an alloy containing them as a main component is preferable.
Examples of the dielectric constituting the dielectric film include metal oxides and metal nitrides.
The infrared shielding layer 36 preferably has a metal thin film or a film structure in which an oxide film, a metal thin film, and an oxide film are laminated in this order.

When the infrared shielding layer 36 is a metal film, the thickness of the metal film is preferably 1 to 100 nm, and preferably 4 to 60 nm from the viewpoint of ensuring the visible light transmittance and efficiently reflecting infrared rays. More preferred.
The thickness of the infrared shielding layer 36 is the second thickness when the film is formed on the surface of the second transparent film 35 so as to have a light interference effect in order to achieve both infrared reflectance and visible light transmittance. From the point that it is necessary to be thin enough not to peel from the transparent film 35, about 1 to 5000 nm is preferable, and about 10 to 3000 nm is more preferable.
From the viewpoint that the visible light reflectance of the infrared shielding layer 36 does not impair visibility, the visible light reflectance on the surface of the first transparent substrate 10 and the visible light reflectance on the surface of the second transparent substrate 20 are the same. The total is preferably lower than the total, specifically 20% or less, particularly 10% or less.

(Method for producing light scattering sheet)
The light scattering sheet 30 can be manufactured by the following procedure, for example.
A paste containing the photocurable resin and the light scattering material 33 is prepared.
A metal is vapor-deposited on the surface of the second transparent film 35 to form an infrared shielding layer 36 made of a metal thin film.
A paste is applied to the surface of the infrared shielding layer 36, and the first transparent film 31 is overlaid on the paste.
The paste is irradiated with light (ultraviolet rays or the like) from the side of the first transparent film 31 to cure the photocurable resin, thereby forming a light scattering layer 34 in which the light scattering material 33 is dispersed in the transparent resin 32. Thus, the light scattering sheet 30 is obtained.

(Optical characteristics of transmissive transparent screen)
The total light transmittance of the transmissive transparent screen 1 is preferably 1% or more, more preferably 5% or more, from the viewpoint of good transparency of the scene seen from the other side of the transmissive transparent screen 1 when viewed from the observer side. 25% or more is more preferable, and 50% or more is more preferable. The total light transmittance of the transmissive transparent screen 1 is measured with respect to light incident from the first surface A side and transmitted to the second surface B side.

  The haze of the transmissive transparent screen 1 is preferably 4% or more, more preferably 8% or more, from the viewpoint of securing screen gain and viewing angle. The haze of the transmissive transparent screen 1 is preferably 50% or less, more preferably 30% or less, and more preferably 25% or less from the viewpoint of the transparency of a scene seen from the transmissive transparent screen 1 when viewed from the observer side. Further preferred. The haze of the transmissive transparent screen 1 is measured with respect to light incident from the first surface A side and transmitted to the second surface B side.

  The total light reflectance at a wavelength of 800 nm of the transmissive transparent screen 1 is preferably higher than the total light reflectance at a wavelength of 589 nm of the transmissive transparent screen 1 from the viewpoint of shielding infrared rays and avoiding an increase in indoor temperature. When the infrared ray shielding layer 36 is a metal film, the infrared ray shielding layer 36 is a metal film by adjusting the film thickness of each film constituting the multilayer film. It can be controlled by selecting the appropriate type. The total light reflectance of the transmissive transparent screen 1 is measured with respect to light incident from the second surface B side and reflected to the second surface B side.

  The refractive index difference between adjacent layers in the transmissive transparent screen 1 is preferably within 0.2 from the viewpoint that the reflectance at each layer interface is suppressed to within 0.5%, and the reflectance at each layer interface is 0.1. From the point which becomes about%, 0.1 or less is more preferable.

<Video display system>
FIG. 1 is a schematic configuration diagram showing an example of a video display system of the present invention.
The video display system includes a transmissive transparent screen 1 and a projector 200 installed in a space on the first surface A side of the transmissive transparent screen 1.

(Projector)
The projector 200 only needs to be able to project the image light L onto the transmissive transparent screen 1. Examples of the projector 200 include a known projector. The projector can project the image light L from a close distance of 10 to 90 cm, can reduce the space of the image display system, and can project the image light L with a large incident angle. A short focus projector is preferable because it is difficult for a person to cross between 200 and the transmissive transparent screen 1.

<Video display method>
In the transmissive transparent screen 1, as shown in FIG. 1, the image light L projected from the projector 200 and incident from the first surface A of the transmissive transparent screen 1 is scattered by the light scattering layer 34. The image is formed and displayed as an image so as to be visible to an observer X on the opposite side of the projector 200.

  The light of the scene on the first surface A side is incident on the transmissive transparent screen 1 from the first surface A, and then partially scattered in the light scattering layer 34 and the rest is transmitted. Thereby, when the image light L is not projected onto the transmissive transparent screen 1 from the projector 200, the observer X on the second surface B side can see through the scene on the first surface A side. Similarly, after the light of the scene on the second surface B side is incident on the transmissive transparent screen 1 from the second surface B, a part of the light is scattered in the light scattering layer 34 and the rest is transmitted. Thereby, when the image light L is not projected onto the transmissive transparent screen 1 from the projector 200, the observer on the first surface A side can see through the scene on the second surface B side.

  In the transmissive transparent screen 1, sunlight L <b> 1 passes through the transmissive transparent screen 1 as shown in FIG. 1. However, since the transmissive transparent screen 1 has the infrared shielding layer 36, the infrared shielding layer 36 shields at least a part of infrared rays contained in the sunlight L1 (reflects when the infrared shielding layer 36 is a metal thin film). For this reason, the amount of infrared light that passes through the transmissive transparent screen 1 is suppressed.

<Action mechanism>
Since the transmissive transparent screen 1 described above can transmit light, it is possible to see through the scene beyond the transmissive transparent screen 1 as viewed from the observer.
Further, since the transmissive transparent screen 1 described above has the light scattering layer 34, the transmissive transparent screen 1 is displayed on the transmissive transparent screen 1 as viewed from the observer when the image light L is projected from the projector 200. Can be viewed.
Further, since the transmissive transparent screen 1 described above has the infrared shielding layer 36, the amount of infrared light that passes through the transmissive transparent screen 1 can be suppressed.

<Other embodiments>
The transmission type transparent screen of the present invention is not limited to the transmission type transparent screen 1 of FIG. 1 as long as it has a light scattering layer and an infrared shielding layer. Hereinafter, the same components as those of the transmissive transparent screen 1 of FIG.

As shown in FIG. 2, the transmissive transparent screen may be a transmissive transparent screen 1 a in which an infrared shielding layer 36 and a light scattering layer 34 are sequentially formed on the surface of the second transparent substrate 20.
Moreover, as shown in FIG. 3, even if it is the transmission type transparent screen 1b which bonded the 1st transparent base material 10 through the contact bonding layer 12 to the surface by the side of the light-scattering layer 34 of the transmission type transparent screen 1a. Good.

  The transmission type transparent screen includes a first transparent base material 10 and a second transparent base material 20 having an infrared shielding layer 36 formed on the surface, and a light scattering layer 34 using an adhesive material as a transparent resin. It may be a transmissive transparent screen that is bonded together. In this case, the infrared shielding layer 36 may be in contact with the light scattering layer 34, and conversely, may be located in the outermost layer of the transmissive transparent screen.

The transmission type transparent screen may be a transmission type transparent screen in which the first transparent substrate 10 and the second transparent substrate 20 are omitted, that is, the light scattering sheet 30 itself. The light scattering sheet 30 can be attached to an existing window glass or the like using an adhesive layer. The light scattering sheet 30 can be deformed and is suitable for forming a transmissive transparent screen having a curved surface.
Moreover, in the multi-layer glass having two glass plates and a frame-like spacer interposed between the glass plates so that a gap is formed between the glass plates, on the inner surface of one glass plate, The light scattering sheet 30 may be attached.

  The transmission type transparent screen may be a transmission type transparent screen in which a light scattering layer 34 is formed on the surface opposite to the infrared shielding layer 36 of one transparent base material having the infrared shielding layer 36 formed on the surface. Good. Even if another layer is present between the light scattering layer 34 and the infrared shielding layer 36 as in this transmissive transparent screen, the effect of the present invention can be exhibited.

The light scattering layer is not limited to the light scattering layer 34 in FIG. 1, and is a light scattering layer including a transparent layer and a plurality of light scattering portions arranged in parallel to each other at a predetermined interval inside the transparent layer. There may be.
FIG. 4 is a layer configuration diagram showing another example of the transmissive transparent screen.
In the transmissive transparent screen 1 c, a light scattering sheet 40 is disposed between the first transparent substrate 10 and the second transparent substrate 20.
The first transparent substrate 10 and the light scattering sheet 40 are bonded by the adhesive layer 12, and the second transparent substrate 20 and the light scattering sheet 40 are bonded by the adhesive layer 22.

  The light scattering sheet 40 includes: a first transparent film 31; a second transparent film 35; a transparent layer 42 provided between the first transparent film 31 and the second transparent film 35; A plurality of light-scattering portions 43 extending in the plane direction and having a right-angled cross-section in the direction perpendicular to the longitudinal direction, arranged in parallel to each other at a predetermined interval; transparent layer 42 and second layer And an infrared shielding layer made of at least one selected from the group consisting of a metal thin film, a semiconductor thin film, and a dielectric thin film provided between the transparent film. Hereinafter, a structure in which a plurality of light scattering portions 43 extending in a one-dimensional direction in a stripe shape is sometimes described as a louver structure.

The transparent layer 42 is preferably a transparent resin layer.
As the transparent resin constituting the transparent resin layer, the same resin as the transparent resin 32 of the light scattering sheet 30 described above may be used.
The thickness of the transparent layer 42 is preferably 10 to 200 μm. When the thickness of the transparent layer 42 is 10 μm or more, the interval between the light scattering portions 43 is also 10 μm or more, and the effect of the louver structure is sufficiently exhibited. If the thickness of the transparent layer 42 is 200 μm or less, it is easy to form the transparent layer 42 by a roll-to-roll process.

  Examples of the material for the light scattering portion 43 include the same materials as those for the light scattering layer 34 described above.

  The interval between the light scattering portions 43 (the distance between the centers of the adjacent light scattering portions 43) is preferably 10 to 250 μm, and more preferably 10 to 100 μm. If the interval between the light scattering portions 43 is 10 μm or more, the light scattering portions 43 are easily formed. If the space | interval of the light-scattering part 43 is 250 micrometers or less, the light-scattering part 43 will be hard to visually recognize.

  10-70% of the space | interval of the light-scattering part 43 is preferable, and the width | variety (direction orthogonal to the longitudinal direction of the light-scattering part 43 of the surface direction of the light-scattering sheet 40) of the light-scattering part 43 is more preferable. . If the width of the light scattering portion 43 is 10% or more of the interval between the light scattering portions 43, the light scattering portion 43 is easily formed. If the width of the light scattering portion 43 is 70% or less of the interval between the light scattering portions 43, the transmittance of the light scattering portion 43 and the transparency of the scene seen beyond the transmissive transparent screen 1c when viewed from the observer side. Will improve.

  The ratio of the height of the light scattering portion 43 to the width of the light scattering portion 43 (the direction orthogonal to the surface direction of the light scattering sheet 40), that is, the aspect ratio, is obliquely incident while maintaining the straight light transmittance of the scene. 1 or more is preferable, 1.5 or more is more preferable, and 2 or more is more preferable from the point which scatters the light from a light source with high gain.

  The shape of the cross section orthogonal to the longitudinal direction of the light scattering portion 43 is not limited to a right triangle as shown in the illustrated example, and may be another triangle, trapezoid, bell shape, or the like.

  The infrared shielding layer only needs to have an infrared shielding function, and is not limited to a material selected from the group consisting of a metal thin film, a semiconductor thin film, and a dielectric thin film as in the illustrated example. As an infrared shielding layer, the infrared shielding layer in a well-known infrared shielding glass and an infrared shielding film is mentioned. As infrared shielding glass, the heat ray shielding glass described in Unexamined-Japanese-Patent No. 5-238778, glass with the infrared shielding film described in Unexamined-Japanese-Patent No. 2005-194169, etc. are mentioned, for example. Examples of the infrared shielding film include an infrared reflecting film described in JP 2012-196954 A, a film using cholesteric liquid crystal, and a film in which particles whose silver shape is controlled are dispersed.

In the transmissive transparent screen, the image light from the projector may be projected onto the second transparent substrate side (or the second transparent film side). In this case, the surface on the second transparent substrate side (or the second transparent film side) is the first surface A. That is, the infrared shielding layer 36 is positioned closer to the first surface A than the light scattering layer 34.
When the infrared shielding layer 36 is provided at a position closer to the first surface A than the light scattering layer 34, it is possible to obtain the effect of scattering the reflected infrared rays, and to suppress the temperature rise of the road surface due to the reflected light. An effect of suppressing temperature rise can be obtained.
On the other hand, when the infrared shielding layer 36 is provided at a position closer to the second surface B than the light scattering layer 34 as in the illustrated example, before the incident sunlight L1 is irregularly reflected by the light scattering layer 34. , And can maintain a high infrared shielding effect.
Further, when the short focus projector is used, when the distance from the projector to the transmissive transparent screen is increased, the angle at which the image light L is incident on the infrared shielding layer 36 is increased, and the color of the light incident on the light scattering layer 34 is increased. The balance changes greatly depending on the distance from the projector. From the viewpoint of suppressing this change in color balance, it is preferable to dispose the light scattering layer 34 between the infrared shielding layer 36 and the projector.

Hereinafter, the present invention will be described in more detail using examples, but the present invention is not limited to these examples.
Example 1 is an example and Example 2 is a comparative example.

(Example 1)
Ultraviolet curable resin (manufactured by Hitachi Chemical Co., Ltd., Hitaroid (registered trademark) 7981, specific gravity 1.1) is added with 0.05% by volume of titanium oxide fine particles (average particle size: 0.2 μm, specific gravity 4.2). The paste of Example 1 mixed with was prepared.

On the surface of a transparent polyethylene terephthalate (hereinafter referred to as PET) film (manufactured by Toyobo Co., Ltd., Cosmo Shine (registered trademark) A4300, thickness: 75 μm), aluminum is physically vapor-deposited by a vacuum vapor deposition method to form an aluminum thin film (thickness). : 8 nm) was formed.
The paste of Example 1 was applied to the surface of the infrared shielding layer, and another PET film was overlaid on the paste.
The paste was irradiated with ultraviolet rays to cure the ultraviolet curable resin to form a light scattering layer having a thickness of 20 μm, and the light scattering sheet of Example 1 was obtained.

  Soda-lime glass plate (Matsunami Glass, thickness: 3 mm), polyvinyl butyral (hereinafter referred to as PVB) film (Solutia, Saflex RK11l, thickness: 375 μm), light scattering sheet of Example 1, PVB film ( Thickness: 375 μm) and soda lime glass plate (thickness: 3 mm) were laminated in this order, and vacuum thermocompression bonding was carried out to obtain a transmission type transparent screen of Example 1. Table 1 shows the evaluation results of the transmission type transparent screen of Example 1. Moreover, the transmission spectrum of the transmission type transparent screen of Example 1 is shown in FIG.

(Example 2)
A transmissive transparent screen of Example 2 was obtained in the same manner as Example 1 except that no infrared shielding layer was formed. Table 1 shows the evaluation results of the transmissive transparent screen of Example 2. Moreover, the transmission spectrum of the transmission type transparent screen of Example 1 is shown in FIG.

The evaluation criteria in the table are as follows.
(Sight transparency)
The transparency of the sight seen beyond the transmissive transparent screen as viewed from the observer was evaluated according to the following criteria.
0: Good.
1: Good when the near side is dark or the outside light is small.
2: At a level where rough recognition is possible.
3: The scene cannot be seen through.

(Video visibility)
The visibility of the image displayed on the transmissive transparent screen as viewed from the observer was evaluated according to the following criteria.
0: Good.
1: Good when the surroundings are dark.
2: At a level where rough recognition is possible.
3: The image cannot be visually recognized.

  Further, the transmission spectrum of the transmissive transparent screen was measured using a spectrophotometer. The transmission type transparent screen was arranged so that light was transmitted in the order of the infrared shielding layer and the light scattering layer. An integrating sphere was used to detect the transmitted light, and both diffused light and light transmitted without diffusion were detected.

  The transmission type transparent screen of the present invention is useful as a transparent member used for a showcase of goods, etc .; an exhibition case of art, etc .; a window of a building, a showroom, a vehicle, etc .; a glass door; Specifically, it is possible to see through the view of the transparent member as seen from the observer side, and to transmit information such as explanation of products, state of various devices, destination guidance, transmission items, etc. to the observer. When displaying the operation screens of various devices to the observer, or when making it impossible to see through the scene behind the transparent member for privacy protection, security, etc. It is useful as a transparent screen that displays the image light projected from the viewer as an image to the observer.

DESCRIPTION OF SYMBOLS 1 Transmission type transparent screen 1a Transmission type transparent screen 1b Transmission type transparent screen 1c Transmission type transparent screen 10 1st transparent base material 12 Adhesive layer 20 2nd transparent base material 22 Adhesive layer 30 Light-scattering sheet 31 1st transparent film 32 Transparent resin 33 Light scattering material 34 Light scattering layer 35 Second transparent film 36 Infrared shielding layer 40 Light scattering sheet 42 Transparent layer 43 Light scattering portion 101 Transmission type transparent screen 110 First transparent substrate 120 Second transparent group Material 132 Transparent resin 133 Light scattering material 134 Light scattering layer 200 Projector A First surface B Second surface L Video light L1 Sunlight X Observer

Claims (6)

  A transmissive transparent screen having a light scattering layer and an infrared shielding layer. The total light transmittance is 1% or more,
Haze is 4-50%,
The transmissive transparent screen according to claim 1, wherein the total light reflectance at a wavelength of 800 nm is higher than the total light reflectance at a wavelength of 589 nm.   The transmissive transparent screen according to claim 1, wherein the light scattering layer includes a transparent resin and a light scattering material.   The transmissive transparent screen according to any one of claims 1 to 3, wherein the infrared shielding layer is at least one selected from the group consisting of a metal thin film, a semiconductor thin film, and a dielectric thin film. The transmissive transparent screen according to any one of claims 1 to 4,
An image display system comprising: a projector installed at a position where image light can be projected onto the transmissive transparent screen.   An image display method for projecting image light from a projector onto the transmissive transparent screen according to claim 1 to display an image.

Images