TW201935126A - Video projection system - Google Patents

Abstract

To provide a video projection system comprising a transparent screen and a video projection unit arranged on one surface side of the transparent screen, the video projection system capable of preventing the light passing through the transparent screen from reaching a rear-side object different from the transparent screen and forming an unwanted image on the object after video light from the video projection unit forms an image on the transparent screen. The present invention provides a video projection system comprising a transparent screen, a transparent viewing-angle control film, and a video projection unit arranged on one surface side of the transparent screen, wherein the transparent viewing-angle control film scatters the light transmitted through the transparent screen with the projection angle of video light from the video projection unit being restricted to within a range of viewing angles controlled by the transparent viewing-angle control film. Thus, it is possible to prevent the transmitted light from forming an unwanted image and from hindering a pleasant view by preventing the transmitted light from reaching a rear-side object different from the transparent screen, and to prevent the transmitted light from jeopardizing traffic safety due to the transmitted light reaching pedestrians and passing vehicles.

Description

Image projection system

The invention relates to an image projection system, which comprises a transparent screen, a transparent viewing angle control film, and an image projection unit configured to project an image within a range of the viewing angle control angle of the transparent viewing angle control film.

Previously, in an image projection system, an image projection unit was generally used to project image light onto an image subject such as a screen, and an observer observed the image. In recent years, using such an image projection system, there has been an increasing demand for projected display of product information or advertisements on display windows of department stores or the transparent partitions of event spaces. In the image projection system for realizing such a requirement, the observer is required to see a good image from either side of the display window or the transparent partition plate, and the transparency of the display window or the transparent partition plate is not impaired. In order to cope with such a request, a transparent screen may be attached to a display window or a transparent partition and used. However, the light transmitted through the transparent screen among the image light projected from the image projection unit may cause objects other than the transparent screen to cause instability. Necessary imaging may hinder comfortable recognition, or may be an obstacle to performance. In addition, when a transparent screen is arranged on a glass surface of a store such as a convenience store to project an image, it is assumed that transmitted light may be irradiated to a pedestrian or a passing vehicle, which may hinder safe traffic.

In response to the problems described above, reflective screens having a surface layer having a specific surface shape on the side of the image projection unit have been proposed (Patent Documents 1 and 2). However, the solutions described in Patent Documents 1 and 2 only stop at preventing the image light reflected on the surface of the reflective screen from entering the ceiling, and cannot prevent the transmitted light from imaging on objects other than the transparent screen.

Furthermore, it has been proposed to use light from an image projection unit as polarized light, and to eliminate transmitted light by combining it with a polarizing plate (Patent Document 3). However, in the solution described in Patent Document 3, when the light from the image projection unit is polarized, the problem of losing 50% of the total light amount and causing a decrease in brightness occurs.
[Prior technical literature]
[Patent Literature]

Patent Literature 1: Japanese Patent Laid-Open No. 2013-130837 Patent Literature 2: Japanese Patent Laid-Open No. 2014-71278 Patent Literature 3: WO2017 / 150408
Patent Literature 4: Japanese Patent Laid-Open No. 51-44186 Patent Literature 5: Japanese Patent Laid-Open No. 50-26885 Patent Literature 6: Japanese Patent Laid-Open No. 2-97904 Patent Literature 7: Japanese Patent No. 2547417 Bulletin

[Problems to be solved by the invention]

The present invention is made in view of the above technical problems, and an object thereof is to provide an image projection system having a transparent screen and an image projection unit disposed on the front side of the transparent screen, and after the image light from the image projection unit is imaged on the transparent screen , Can prevent light from passing through the transparent screen to reach objects behind the transparent screen and cause unnecessary imaging, prevent interference with comfortable viewing, or prevent pedestrians or passing vehicles from passing through the light to prevent traffic safety.
[Technical means to solve the problem]

The inventors made intensive research in order to solve the above technical problems, and found that in an image projection system provided with a transparent screen, a transparent viewing angle control film, and an image projection unit disposed on the front side of the transparent screen, the image projection unit The range of the projection angle of the image light is within the range of the viewing angle control angle of the transparent viewing angle control film. The transparent viewing angle control film scatters the transmitted light, which can solve the above technical problems. The present invention has been completed based on this knowledge.

That is, according to the first embodiment of the present invention,
An image projection system is provided, which includes a transparent screen, a transparent viewing angle control film disposed on one side of the transparent screen, and an image projection unit disposed on the transparent screen side, and the image projection unit is based on an image from the image projection unit. The projection angle of light is arranged in such a manner that the range of the viewing angle control angle of the transparent viewing angle control film described above,
The image light is imaged on the transparent screen.
The transparent viewing angle control film scatters image light transmitted through the transparent screen.

According to a second aspect of the present invention,
An image projection system is provided. The image projection system includes a transparent screen, a transparent viewing angle control film disposed on one side of the transparent screen, and an image projection unit disposed on the transparent angle control film. The image projection unit is based on the image projection unit. The projection angle of the image light is arranged in such a manner that the angle of the viewing angle of the transparent viewing angle control film is within the range,
Scattering the image light by the transparent viewing angle control film,
The image light passing through the transparent viewing angle control film is imaged on the transparent screen.

In the first and second embodiments of the present invention, it is preferable that the viewing angle control angle of the transparent viewing angle control film is 10 degrees or more and 80 degrees or less with respect to the orthogonal plane of the transparent viewing angle control film from the front side.

In the above-mentioned first and second embodiments of the present invention, it is preferable that the lower limit value of the range of the observation angle of the observer is greater than the transparency when the image projection unit is positioned above the observer. The upper limit of the viewing angle of the viewing angle control film.

In the first and second embodiments of the present invention, it is preferable that the upper limit value of the range of the observer's viewing angle is smaller than the transparent value when the image projection unit is positioned below the observer. The lower limit of the viewing angle of the viewing angle control film.

In the first and second embodiments of the present invention, it is preferable that the parallel light transmittance of the transparent viewing angle control film in the range of the viewing angle control angle is 0% or more and less than 40%. The parallel light transmittance outside the range is 60% to 92%.

In the first and second embodiments of the present invention, it is preferable that the transparent screen and the transparent viewing angle control film constitute a laminated body.

In the first and second embodiments of the present invention, it is preferable that the laminated body includes a transparent layer between the transparent screen and the transparent viewing angle control film.

In the first and second embodiments of the present invention, the haze value of the transparent screen is preferably 35% or less.

In the first and second embodiments of the present invention, it is preferable that the transparent screen includes light-reflecting fine particles.
[Effect of the invention]

According to the first embodiment of the present invention, in an image projection system including a transparent screen, a transparent viewing angle control film disposed on the rear side of the transparent screen, and an image projection unit disposed on the front side of the transparent screen, the image light from the image projection unit After imaging on a transparent screen, it prevents unnecessary light from being caused by the light that passes through the transparent screen to reach objects behind the transparent screen, which prevents interference with comfortable viewing or prevents pedestrians or passing vehicles from being irradiated with light to prevent traffic safety . According to such an image projection system, good performances and advertisements can be achieved without hindering traffic safety.

Moreover, according to the second embodiment of the present invention, a transparent viewing angle is used in an image projection system including a transparent screen, a transparent viewing angle control film disposed on the front side of the transparent screen, and an image projection unit disposed on the front side of the transparent viewing angle control film. The control film scatters the image light from the image projection unit and loses linearity, and then reaches a transparent screen for imaging, which can realize brightness and wide viewing angle. In addition, the light transmitted through the transparent screen is scattered, which can prevent unnecessary imaging due to objects that reach behind the transparent screen, prevent interference with comfortable viewing, or prevent pedestrians or passing vehicles from being blocked by light Safety. According to such an image projection system, good performances and advertisements can be achieved without hindering traffic safety.

＜ Image projection system ＞
The image projection system according to the first embodiment of the present invention includes a transparent screen, an image projection unit disposed on the front side with respect to the transparent screen, and a transparent viewing angle control film disposed on the rear side with respect to the transparent screen. In such an image projection system, after the image light projected from the image projection unit is imaged on a transparent screen, the light passing through the transparent screen is scattered by a transparent viewing angle control film. As a result, the image light passing through the transparent screen does not cause unnecessary imaging on objects behind the transparent screen, and observers located on the image projection unit side (front side) of the transparent screen will not recognize unnecessary imaging. According to such an image projection system, good performances and advertisements can be realized.

In the present invention, "transparent" is only required to have a degree of transparency capable of achieving transparency through transmission depending on the use, and also includes translucency.
In the present invention, the "angle-of-view control angle of the transparent angle-of-view control film" can be defined by an angle formed from the base point side by an orthogonal plane (vertical line) with respect to the thickness direction of the transparent angle-of-view control film. Specifically, in the case of using the image projection unit as a base point, an angle formed by an orthogonal plane (perpendicular line) with respect to the thickness direction of the transparent viewing angle control film from the end portion of the image projection unit side is specified. In the case where the observer (viewpoint) is the base point, the angle formed by the orthogonal plane (vertical line) with respect to the thickness direction of the transparent viewing angle control film from the observer (viewpoint) side is specified.
In the present invention, the "angle range of the observer" is defined by the angle formed by the observer (viewpoint) from the observer (viewpoint) side with respect to the orthogonal plane (perpendicular line) of the transparent viewing angle control film.
Moreover, an angle formed from the observer side may specify a side above the line of sight with a positive value, and a side below the line of sight with a negative value.
In the present invention, the “front side” refers to the direction of the viewer-side display surface of the transparent screen, and the “rear side” refers to the direction of the transparent screen on the side opposite to the viewer-side display surface.

A conceptual diagram of the image projection system according to the first embodiment of the present invention is shown in FIG. 1. The image projection system shown in FIG. 1 includes a transparent screen 11, a transparent viewing angle control film 12 disposed on the rear side of the transparent screen, and an image projection unit 13 disposed on the front side of the transparent screen. By allowing the range 14 of the projection angle of the image light from the image projection unit 13 to be within the range 15 of the angle of view control of the transparent viewing angle control film 12, the transmitted light reaches the range of 18 (the dotted line portion) of the transparent view control film 12 Diffusion and scattering do not cause unnecessary imaging on objects disposed behind the transparent viewing angle control film 12. On the other hand, when the image light reaches the range (solid line portion) of 19 of the transparent viewing angle control film 12, the parallel light will not be diffusely scattered and directly reach the object on the rear side of the transparent viewing angle control film 12, which may cause instability. Necessary imaging. Furthermore, the range of the viewing angle control angle from the side of the image projection unit 13 to the transparent viewing angle control film 12 on the side of the transparent viewing angle control film 12 at the end (perpendicular line) 16 from the image projection unit 13 side. The angle formed by the range farthest from the image projection unit 13 in 15 is denoted by α.

In the image projection system according to the first embodiment of the present invention, the transparent screen and the transparent viewing angle control film preferably constitute a laminated body. By making the transparent screen and the transparent viewing angle control film into a laminated body, it is possible to prevent the transparent screen or the transparent viewing angle control film from reflecting at the air interface through light or unnecessary diffuse reflection, further improving the contrast. Moreover, by making a laminated body, the arrangement of the image projection system becomes easy.

A conceptual diagram of an image projection system according to a second embodiment of the present invention is shown in FIG. 2. The image projection system shown in FIG. 2 includes a transparent screen 21, a transparent viewing angle control film 22 disposed on the front side of the transparent screen 21, and an image projection unit 23 disposed on the front side of the transparent viewing angle control film 22. By allowing the range 24 of the projection angle of the image light from the image projection unit 23 to be within the range 25 of the angle of view control of the transparent viewing angle control film 22, the image light is scattered by the transparent view control film 22 to lose linearity After that, the diffused light reaches the transparent screen 21 for imaging, and can realize high brightness and wide viewing angle. Since light other than the imaged image light is scattered, it does not cause unnecessary imaging on objects arranged behind the transparent screen 21. In addition, the orthogonal plane (vertical line) 26 with respect to the thickness direction at the end of the transparent viewing angle control film 22 on the image projection unit 23 side is the range of the viewing angle control angle of the transparent viewing angle control film 22 from the image projection unit 23 side. The angle formed by the farthest distance from the image projection unit 23 in 25 is denoted by α.

In the image projection system according to the second embodiment of the present invention, the transparent screen and the transparent viewing angle control film preferably constitute a laminated body. By making the transparent screen and the transparent viewing angle control film into a laminated body, it is possible to prevent the transparent screen or the transparent viewing angle control film from reflecting at the air interface through light or unnecessary diffuse reflection, further improving the contrast. Moreover, by making a laminated body, the arrangement of the image projection system becomes easy. Furthermore, by making a laminated body, the image light diffused through the transparent viewing angle control film is imaged on a transparent screen before dissipating, thereby obtaining a good image with less deterioration in defocus or resolution.

In the second embodiment of the present invention, a conceptual diagram of an image projection system in which a transparent screen and a viewing angle control film constitute a laminated body is shown in FIG. 3. The image projection system shown in FIG. 3 includes a laminated body including a transparent screen 31, a transparent viewing angle control film 32 disposed on the front side of the transparent screen 31, and a transparent layer 38 disposed between the transparent screen 31 and the transparent viewing angle control film 32, and An image projection unit 33 disposed on the front side of the transparent viewing angle control film. The projection angle range 34 of the image light from the image projection unit 33 is closed within the viewing angle control angle range 35 of the transparent viewing angle control film 32, and the image light is scattered by the transparent viewing angle control film 32 to lose linearity. After that, the diffused light reaches the transparent screen 31 for imaging, and high brightness and wide viewing angle can be realized. Light other than the imaged image light is scattered, so that objects outside the rear side of the transparent screen 31 do not cause unnecessary imaging. Furthermore, the range of the viewing angle control angle of the transparent direction control film 32 from the side of the image projection unit 33 to the transparent viewing angle control film 32 at the end in the thickness direction (vertical line) 36 The angle formed by the farthest distance from the image projection unit 33 in 35 is denoted by α.

A conceptual diagram showing an observation angle between a projection image system and an observer in a second embodiment of the present invention is shown in FIG. 4. The image projection system shown in FIG. 4 includes a transparent screen 41, a transparent viewing angle control film 42 disposed on the front side of the transparent screen 41, and an image projection unit 43 disposed on the front side of the transparent viewing angle control film 42. The observer 47 is located on the front side with respect to the transparent screen 41 and the viewing angle control film 42. The image projection unit 43 is disposed on the head of the observer 47 so that the range 44 of the projection angle of the image light from the image projection unit 43 is within the range 45 of the angle of view control of the transparent viewing angle control film 42. The lower limit value 49l of the range 49 of the viewing angle of the observer 47 is larger than the upper limit value 45u of the range 45 of the viewing angle control angle of the transparent viewing angle control film 42. It is assumed that the range 45 of the viewing angle of the transparent viewing angle control film 42 coincides with the range 49 of the viewing angle of the observer 47. In this case, the field of view of the overlapping portion is blocked and cannot be observed through the transparent viewing angle control film 42 and the transparent screen 41 Background, transparency is impaired. Furthermore, the range of the viewing angle control angle of the transparent direction control film 42 from the end of the transparent viewing angle control film 42 side of the image projection unit 43 to the transparent viewing angle control film 42 side from the image projection unit 43 side. The angle formed by the farthest distance from the image projection unit 43 in 45 is denoted by α, and the angle formed by the orthogonal plane (vertical line) 48 with respect to the thickness direction of the transparent viewing angle control film 42 from the observer (viewpoint) 47 side These are denoted by β (above the line of sight) and γ (below the line of sight).

A conceptual diagram showing the viewing angle between the projection image system and the observer in the second embodiment of the present invention is shown in FIG. 5. The image projection system shown in FIG. 5 includes a transparent screen 51, a transparent viewing angle control film 52 disposed on the front side of the transparent screen 51, and an image projection unit 53 disposed on the front side of the transparent viewing angle control film 52. The observer 57 is located on the front side with respect to the transparent screen 51 and the viewing angle control film 52. The image projection unit 53 is arranged below the observer 57 so that the range 54 of the projection angle of the image light from the image projection unit 53 is within the range 55 of the angle of view control of the transparent viewing angle control film 52. The upper limit value 59u of the range 59 of the viewing angle of the observer 57 is smaller than the lower limit value 55l of the range 55 of the viewing angle control angle of the transparent viewing angle control film 52. It is assumed that the range 55 of the viewing angle of the transparent viewing angle control film 52 coincides with the range 59 of the viewing angle of the observer 57. In this case, the field of view of the overlapping portion is obstructed and cannot be observed through the transparent viewing angle control film 52 and the transparent screen 51. Background, transparency is impaired. Furthermore, an orthogonal plane (perpendicular line) 56 with respect to the thickness direction of the transparent viewing angle control film 52 on the side of the image projection unit 53 is set to a distance 55 from the viewing angle control angle range 55 of the transparent viewing angle control film 52 on the side of the image projection unit 53. The angle formed by the farthest range of the projection unit 53 is denoted as α, and the angle formed by the orthogonal plane (perpendicular line) 58 with respect to the transparent viewing angle control film 52 from the observer (viewpoint) 57 side is set as β (above the line of sight) ) And γ (below the line of sight).

The following describes the structural elements of the image projection system, namely the image projection unit, the transparent screen, and the transparent viewing angle control film.

<Image projection unit>
The image projection unit used in the image projection system is not particularly limited, as long as it is capable of projecting an image on a transparent screen as described below. For example, a commercially available rear-projection projector or front-projection projector can be used. In particular, since it is easy to adjust the projection angle of the image light to the range of the angle of view control of the transparent angle control film, the WX450ST made by Canon Corporation with lens shift function can be preferably used.

＜ Transparent screen ＞
The transparent screen used in the image projection system is preferably one having a light scattering layer containing a binder and fine particles. The transparent screen may be a single layer composed of only a light scattering layer, or a multilayer body further including a protective layer, a substrate layer, an adhesive layer, and an anti-reflection layer. The transparent screen may be provided with a support such as glass or a transparent partition. This transparent screen can reflect both the visibility of the projection light and the visibility of the transmitted light by diffusely reflecting the projection light emitted from the image projection unit anisotropically.

The transparent screen can be flat or curved. For example, the transparent screen can be preferably used in a glass display window, a head-up display, a wearable display, etc., and can be particularly preferably used as a transparent screen for a short-focus projector.

The haze value of the transparent screen is preferably 35% or less, more preferably 1% or more and 30% or less, and still more preferably 2% or more and 25% or less. The total light transmittance of the transparent screen is preferably 60% to 98%, more preferably 65% to 96%, still more preferably 70% to 94%, and even more preferably 75% to 92%. the following. As long as the haze value and total light transmittance of the transparent screen are within the above ranges, the transparency is high, and the visibility of transmission can be further improved. Furthermore, in the present invention, the haze value and total light transmittance of the transparent screen can be determined using a turbidimeter (manufactured by Nippon Denshoku Industries Co., Ltd., product number: NDH-5000) in accordance with JIS-K-7361 and JIS- K-7136 was measured.

The image clarity of the transparent screen is preferably 65% or more, more preferably 70% or more and 98% or less, still more preferably 75% or more and 97% or less, and even more preferably 80% or more and 96% or less. As long as the image clarity of the transparent screen is within the above range, the image seen through the transparent screen will become extremely clear. In addition, in the present invention, the image sharpness is a value of image sharpness (%) when measured at an optical comb width of 0.125 mm in accordance with JIS K7374.

(Light scattering layer)
The light-scattering layer is composed of a binder and fine particles. As the fine particles, the following light-reflective fine particles can be preferably used. By using such fine particles, light can be diffusely anisotropically reflected in the light-scattering layer, and the use efficiency of light is improved.

The thickness of the light scattering layer is not particularly limited, but from the viewpoints of use, productivity, handling, and transportability, it is preferably 0.1 μm to 20 mm, more preferably 0.2 μm to 15 mm, and still more preferably 1 μm. ~ 10 mm. As long as the thickness of the light scattering layer is within the above range, it is easy to maintain the strength as a screen. The light-scattering layer may be a molded body obtained by using the following organic adhesive or inorganic adhesive, or may be a coating film formed on a substrate including glass, resin, or the like. The light-scattering layer may be a single-layer structure, or may be a multi-layer structure in which two or more layers are laminated by coating or the like, or two or more types of light-scattering layers are bonded together with an adhesive or the like.

In order to obtain a highly transparent film, it is preferable to use a highly transparent adhesive for the light scattering layer. As the adhesive, there are organic adhesives and inorganic adhesives. As the organic adhesives, thermoplastic resins, thermosetting resins, self-crosslinking resins, and radiation-hardening resins can be used. Examples include acrylic resins. , Acrylic urethane resin, polyester acrylate resin, acrylic polyurethane resin, epoxy acrylate resin, polyester resin, polyolefin resin, urethane resin Resin, epoxy resin, polycarbonate resin, cellulose resin, acetal resin, vinyl resin, polystyrene resin, polyamide resin, polyimide resin, melamine resin , Phenol-based resin, silicone-based resin and fluorine-based resin.

Examples of the thermoplastic resin include an acrylic resin, a polyester resin, a polyolefin resin, a vinyl resin, a polycarbonate resin, and a polystyrene resin. Among these, polymethyl methacrylate resin, polyethylene terephthalate resin, polyethylene naphthalate resin, polypropylene resin, cycloolefin resin, and cellulose acetate propionate resin are more preferably used. , Polyvinyl butyral resin, polycarbonate resin and polystyrene resin. These resins can be used alone or in combination of two or more.

Examples of the radiation-hardenable resin include acrylic or urethane-based, acrylic urethane-based or epoxy-based, and silicone-based resins. Among these, those having an acrylic functional group are preferred, such as a polyester resin, polyether resin, acrylic resin, epoxy resin, urethane resin, alkyd resin, Spiro acetal resin, polybutadiene resin, polythiol polyene resin, polyfunctional compounds such as (meth) acrylates, etc., oligomers or prepolymers, and containing relatively large amounts as reactive dilution Monofunctional monomers and polyfunctional monomers such as ethyl (meth) acrylate, ethyl ethyl (meth) acrylate, styrene, methylstyrene, and N-vinyl pyrrolidone, such as polymethylol Propane tri (meth) acrylate, hexanediol (meth) acrylate, tripropylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, pentaerythritol tri (meth) acrylate , Dipentaerythritol hexa (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, and the like. In addition, the radiation-hardenable resin may be a mixture of a thermoplastic resin and a solvent.

Examples of the thermosetting resin include a phenol resin, an epoxy resin, a silicone resin, a melamine resin, a urethane resin, and a urea resin. Among these, epoxy resins and silicone resins are preferred. Examples of the self-crosslinkable resin include a silicone resin, an epoxy resin, a urethane resin, and an acrylic resin.

Examples of the highly transparent inorganic adhesive include water glass, a glass material having a low softening point, and a sol-gel material. Water glass refers to a thick aqueous solution of an alkali silicate and usually contains sodium as an alkali metal. A representative water glass can be represented by Na ₂ O · nSiO ₂ (n: any positive number). As a commercially available product, sodium silicate manufactured by Fuji Chemical Co., Ltd. can be used.

The glass material having a low softening point is preferably a glass having a softening temperature in a range of 150 to 620 ° C, further preferably a softening temperature in a range of 200 to 600 ° C, and most preferably a softening temperature in a range of 250 to 550 ° C. Examples of such glass materials include a mixture of a PbO-B ₂ O ₃ system, a PbO-B ₂ O ₃ -SiO ₂ system, a PbO-ZnO-B ₂ O ₃ system, an acid component, and a metal chloride. Heat-treated and lead-free low softening point glass. In low-softening point glass materials, in order to improve the dispersibility and moldability of fine particles, solvents and high boiling point organic solvents can be mixed.

A sol-gel material is a group of compounds that undergoes hydrolysis, polycondensation, and hardening by the action of heat, light, or a catalyst. For example, it is a metal alkoxide (metal alkoxide), a metal chelate compound, a metal halide, a liquid glass, a spin-on glass, or a reactant thereof, or it may be one containing a catalyst that promotes hardening. Moreover, it is good also as a thing which has a photoreactive functional group, such as an acryl group, in a part of metal alkoxide functional group. They can be used alone or in combination depending on the required physical properties. The hardening system of the sol-gel material refers to a state in which the polymerization reaction of the sol-gel material can sufficiently proceed. The sol-gel material is chemically bonded to the surface of the inorganic substrate during the polymerization reaction and is firmly adhered. Therefore, by using the hardened body of the sol-gel material as the hardened material layer, a stable hardened material layer can be formed.

A metal alkoxide is a compound group obtained by reacting an arbitrary metal species with water or an organic solvent using a hydrolysis catalyst or the like, and is an arbitrary metal species with a hydroxyl group, a methoxy group, an ethoxy group, a propyl group, or an isopropyl group. A group of compounds formed by the bonding of isofunctional groups. Examples of the metal alkoxide include silicon, titanium, aluminum, germanium, boron, zirconium, tungsten, sodium, potassium, lithium, magnesium, and tin.

For example, as the metal alkoxide whose metal species is silicon, dimethyldiethoxysilane, diphenyldiethoxysilane, phenyltriethoxysilane, methyltriethoxysilane (MTES) ), Vinyltriethoxysilane, p-styryltriethoxysilane, methylphenyldiethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane , 3-glycidyloxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3 -Methacryloxypropyltriethoxysilane, 3-propenyloxypropyltriethoxysilane, N-2- (aminoethyl) -3-aminopropylmethyldiethyl Oxysilane, N-2- (aminoethyl) -3-aminopropyltriethoxysilane, 3-aminopropyltriethoxysilane, 3-ureidopropyltriethoxysilane , 3-mercaptopropylmethyldiethoxysilane, 3-mercaptopropyltriethoxysilane, triethoxysilane, diphenylsilanediol, dimethylsilanediol, etc., or these compounds The ethoxy group of the group is substituted with methoxy, propyl, isopropyl, hydroxy The other compounds and other groups. Of these, particularly preferred are tetramethoxysilane (TMOS) and TEOS in which the ethoxy group of triethoxysilane (TEOS) is replaced with a methoxy group. These can be used alone or in combination.

(Solvent)
These organic adhesives and inorganic adhesives may further include a solvent if necessary. As a solvent, the solvent used for a general coating composition can be used, It is not limited to an organic solvent. For example, a hydrophilic solvent typified by water may be used. When the adhesive of the present invention is a liquid, the solvent may not be contained.

Specific examples of the solvent include alcohols such as methanol, ethanol, isopropanol (IPA), n-propanol, butanol, 2-butanol, ethylene glycol, and propylene glycol; hexane, heptane, and octane , Decane, cyclohexane and other aliphatic hydrocarbons; benzene, toluene, xylene, mesitylene, tetramethylbenzene and other aromatic hydrocarbons; diethyl ether, tetrahydrofuran, dioxane and other ethers; acetone, methyl Ketones such as ethyl ketone, isophorone, cyclohexanone, cyclopentanone, N-methyl-2-pyrrolidone; butoxyether, hexyloxyethanol, methoxy-2-propanol, Ether alcohols such as benzyloxyethanol; glycols such as ethylene glycol and propylene glycol; ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate, cellosolve, methyl cellosolve Agent, ethyl cellosolve, carbitol, methyl carbitol, ethyl carbitol, butyl carbitol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, Glycol ethers such as triethylene glycol monomethyl ether and triethylene glycol monoethyl ether; esters such as ethyl acetate, butyl acetate, ethyl lactate, γ-butyrolactone; phenols such as phenol and chlorophenol; N , N- Amines such as dimethylformamide, N, N-dimethylacetamide, and N-methylpyrrolidone; halogens such as chloroform, dichloromethane, tetrachloroethane, monochlorobenzene, and dichlorobenzene Based solvents; carbon disulfide and other heteroelement-containing compounds, water and mixed solvents of these. The amount of the solvent to be added may be appropriately adjusted depending on the type of the binder or the fine particles or the viscosity range suitable for the following manufacturing steps.

(Light reflective fine particles)
The shape of the light-reflective fine particles is not particularly limited, and may be approximately spherical, flake-shaped, or needle-shaped. When the shape of the light-reflective fine particles is approximately spherical, the median diameter of the primary particles is preferably 0.1 to 2500 nm, more preferably 0.2 to 1500 nm, and even more preferably 0.5 to 500 nm. If the median diameter of the primary particles of the light-reflecting fine particles is within the above-mentioned range, a sufficient scattering effect of the projection light can be obtained without impairing visibility, whereby a clear image can be projected on a transparent screen. Furthermore, in the present invention, the median diameter (D ₅₀ ) of the primary particles of the light-reflective fine particles can be determined by a dynamic light scattering method using a particle size distribution measuring device (manufactured by Otsuka Electronics Co., Ltd., trade name: DLS-8000). ) Measured particle size distribution.

When the shape of the light-reflective microparticles is flaky, the average diameter of the primary particles is preferably 0.01 to 100 μm, more preferably 0.05 to 80 μm, still more preferably 0.1 to 50 μm, and even more preferably 0.5 to 30 μm. Furthermore, the average aspect ratio (= average diameter / average thickness of light reflective fine particles) of the light reflective fine particles is preferably 3 to 800, more preferably 4 to 700, still more preferably 5 to 600, and even more preferably 10 ~ 500. If the average diameter and average aspect ratio of the light-reflective particles are within the above-mentioned range, a sufficient scattering effect of the projection light can be obtained without impairing the visibility, and thus a clear image can be projected on a transparent screen. In the present invention, the average diameter of the light-reflective fine particles is measured using a laser diffraction particle size distribution measurement device (manufactured by Shimadzu Corporation, product number: SALD-2300). The average aspect ratio was calculated using SEM (manufactured by Hitachi High-Technologies Corporation, trade name: SU-1500) image.

As the sheet-shaped light-reflective fine particles, a sheet-shaped photoluminescent material can be preferably used. The specular reflectance of the light reflective fine particles is preferably 12.0% or more, more preferably 15.0% or more, and even more preferably 20.0% or more and 80.0% or less. In the present invention, the specular reflectance of the light reflective fine particles is a value measured in the following manner.
(Specular reflectance)
The measurement was performed using a spectrophotometer (manufactured by Konica Minolta, Ltd., product number: CM-3500d). A powder material dispersed in an appropriate solvent (water or methyl ethyl ketone) was applied to a glass slide so that the film thickness became 0.5 mm or more, and dried. About the obtained glass plate with a coating film, the specular reflectance from the coating film part of a glass surface was measured.

As the light-reflecting fine particles, although depending on the type of the binder to be dispersed, for example, aluminum, silver, copper, platinum, gold, titanium, nickel, tin, tin-cobalt alloy, indium, chromium, and oxidation can be used. Metal particles of titanium, alumina and zinc sulfide; photoluminescent materials made of glass coated metal or metal oxide; or photoluminescent materials made of natural mica or synthetic mica coated metal oxide. As the light-reflective fine particles, a commercially available one can be used. For example, aluminum powder manufactured by Yamato Metal Powder Industry Co., Ltd. can be preferably used.

The content of the light-reflective particles in the light-scattering layer can be appropriately adjusted according to the shape, specular reflectance, and the like of the light-reflective particles. For example, the content of the light-reflective fine particles is preferably 0.0001 to 5.0% by mass, more preferably 0.0005 to 3.0% by mass, and even more preferably 0.001 to 2.0% by mass with respect to the adhesive. A light-scattering layer is formed by dispersing light-reflective fine particles into the adhesive at a low concentration within the above range, and anisotropically scatters and reflects the projection light emitted from the light source, thereby improving the visibility and transmission of the projection light. The recognition of light.

Depending on the purpose of the light-scattering layer, in addition to fine particles, previously known additives may be added. Examples of the additives include antioxidants, ultraviolet absorbers, light stabilizers, antistatic agents, release agents, flame retardants, plasticizers, lubricants, and colorants. As the colorant, pigments or dyes such as carbon black, azo-based pigments, anthraquinone-based pigments, and fluorene-based pigments can be used. Further, a liquid crystal compound or the like may be mixed.

(Base material layer)
The substrate layer is a layer for supporting the light scattering layer described above, and can enhance the strength of the transparent screen. The base material layer is a highly transparent material that does not impair the transparency of the transparent screen or the required optical characteristics. For example, it is preferably formed using glass or resin. As such a resin, for example, a highly transparent resin similar to the above-mentioned light scattering layer can be used. In addition, a composite film or sheet obtained by laminating two or more of the above resins may be used. In addition, the thickness of the base material layer may be appropriately changed depending on the material in such a manner that its strength becomes appropriate, and for example, it may be in the range of 10 to 1000 μm.

(The protective layer)
The protective layer is a layer laminated on the front side (viewer side) of the transparent screen, and is a layer for imparting functions such as light resistance, scratch resistance, and stain resistance. The protective layer is preferably formed using a resin that does not impair the transparency of the transparent screen or the required optical characteristics. As the protective layer, a protective film may be bonded using an adhesive or the like, or a resin hardened by ultraviolet rays or electron beams, that is, a radiation-hardening resin, a mixture of a thermoplastic resin and a solvent, and heat may be used. A hardening resin is coated on the surface of a reflective transparent screen and hardened to form a protective layer. Among these, a protective layer is particularly preferably formed using a radiation-hardenable resin.

The film-forming component of the radiation-hardening resin composition is preferably one having an acrylate-based functional group. For example, a relatively low molecular weight polyester resin, polyether resin, acrylic resin, epoxy resin, and amino methyl ester can be used. Oligomers or prepolymers of (meth) acrylates, etc. of polyfunctional compounds such as ester resins, alkyd resins, spiral resins, polybutadiene resins, polythiol polyene resins, polyols and the like, and containing Relatively many monofunctional monomers such as ethyl (meth) acrylate, ethylhexyl (meth) acrylate, styrene, methylstyrene, and N-vinyl pyrrolidone as reactive diluents and many Functional monomers such as polymethylolpropane tri (meth) acrylate, hexanediol (meth) acrylate, tripropylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, Pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, and the like.

In order to make the above-mentioned free-radiation-curable resin composition into an ultraviolet-curable resin composition, acetophenones, benzophenones, and Miebenzylbenzoic acid can be mixed as a photopolymerization initiator. Ester, α-pentyloxime ester, tetramethylthiuram monosulfide, 9-oxosulfur Or mixed with n-butylamine, triethylamine, poly-n-butylphosphine, etc. as a sensitizer and used. Particularly in the present invention, it is preferable to mix acrylic urethane as an oligomer and dipentaerythritol hexa (meth) acrylate as a monomer.

As a hardening method of the radiation-hardening resin composition, the above-mentioned hardening method of the radiation-hardening resin composition is a general hardening method, that is, it can be hardened by irradiation with an electron beam or ultraviolet rays. For example, in the case of electron beam hardening, various electron beam accelerators such as Cockcroft Walton type, Van de Graaff type, resonance transformer type, insulated core transformer type, linear type, high frequency high voltage accelerator type, and high frequency type are used. The emitted electron beam with an energy of 50 ~ 1000 KeV, preferably 100 ~ 300 KeV, can be used in the case of ultraviolet hardening from ultra-high pressure mercury lamp, high pressure mercury lamp, low pressure mercury lamp, carbon arc, xenon arc, metal halogen Ultraviolet rays emitted by light from lamps, etc.

The protective layer can be formed by spin coating, die coating, dip coating, rod coating, flow coating, or roller coating of the above-mentioned light-scattering layer by applying the coating solution of the free radiation (ultraviolet) radiation-curable resin composition. Coating and gravure coating are applied to the surface of the light-scattering layer, and the coating liquid is hardened by the method described above to form the coating liquid. In addition, a fine structure such as a concave-convex structure, a corner pillar structure, and a micro-lens structure can be provided on the surface of the protective layer depending on the purpose.

(Adhesive layer)
The adhesive layer is a layer for attaching a transparent viewing angle control film or a protective film on a transparent screen. The adhesive layer is preferably formed using an adhesive composition that does not impair the transparency of the transparent screen or the required optical characteristics. Examples of the adhesive composition include natural rubber systems, synthetic rubber systems, acrylic resin systems, polyvinyl ether resin systems, urethane resin systems, and silicone resin systems. Specific examples of the synthetic rubber system include styrene-butadiene rubber, acrylonitrile-butadiene rubber, polyisobutylene rubber, isobutylene-isoprene rubber, styrene-isoprene block copolymer, Styrene-butadiene block copolymer, styrene-ethylene-butene block copolymer. Specific examples of the silicone resin system include dimethyl polysiloxane. These adhesives can be used alone or in combination of two or more. Among these, an acrylic adhesive is preferable.

The acrylic resin adhesive is obtained by polymerizing at least an alkyl (meth) acrylate monomer. It is usually a copolymer of an alkyl (meth) acrylate monomer having an alkyl group having about 1 to 18 carbon atoms and a monomer having a carboxyl group. In addition, (meth) acrylic acid means acrylic acid and / or methacrylic acid. Examples of the alkyl (meth) acrylate monomer include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, and second acrylic (meth) acrylate Ester, n-butyl (meth) acrylate, second butyl (meth) acrylate, third butyl (meth) acrylate, isoamyl (meth) acrylate, n-hexyl (meth) acrylate, (formyl) (Cyclo) hexyl acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, undecyl (meth) acrylate, and (formyl) Based) lauryl acrylate and the like. The above-mentioned (meth) acrylic acid alkyl ester is usually copolymerized in an acrylic adhesive at a ratio of 30 to 99.5 parts by mass.

Examples of the monomer having a carboxyl group for forming an acrylic resin adhesive include (meth) acrylic acid, itaconic acid, butenoic acid, maleic acid, monobutyl maleate, and β-carboxyethyl acrylate. Carboxyl-containing monomer.

In the acrylic resin adhesive, in addition to the above, a monomer having other functional groups may be copolymerized within a range that does not impair the characteristics of the acrylic resin adhesive. Examples of the monomer having another functional group include a hydroxyl-containing monomer such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and allyl alcohol; (meth) Acrylamide-containing monomers such as acrylamide, N-methyl (meth) acrylamide, and N-ethyl (meth) acrylamide; N-methylol (meth) acrylamide and diamine Monomers containing methylamino and methylol groups such as methylol (meth) acrylamide; containing aminomethyl (meth) acrylate, dimethylaminomethyl (meth) acrylate, and vinylpyridine Monomers having functional groups such as amine-based monomers; epoxy-containing monomers such as allyl glycidyl ether and (meth) acrylic acid glycidyl ether. In addition, examples include fluorine-substituted alkyl (meth) acrylate, (meth) acrylonitrile, and aromatic compounds containing vinyl groups such as styrene and methylstyrene, vinyl acetate, and halogenation. Ethylene compounds, etc.

For the acrylic resin adhesive, in addition to the monomers having other functional groups as described above, other monomers having an ethylenic double bond can also be used. Examples of the monomer having an ethylenic double bond include diesters of α, β-unsaturated dibasic acids such as dibutyl maleate, dioctyl maleate, and dioctyl fumarate; acetic acid; Vinyl esters such as vinyl esters and vinyl propionates; vinyl ethers; vinyl aromatic compounds such as styrene, α-methylstyrene and vinyl toluene; (meth) acrylonitrile and the like. In addition to the monomer having an ethylenic double bond as described above, a compound having two or more ethylenic double bonds may be used in combination. Examples of such compounds include divinylbenzene, diallyl maleate, diallyl phthalate, ethylene glycol di (meth) acrylate, and trimethylolpropane tri (methyl) ) Acrylate, methylenebis (meth) acrylamide and the like.

Furthermore, in addition to the monomers as described above, monomers having an alkoxyalkyl chain and the like can also be used. Examples of the alkoxyalkyl (meth) acrylate include 2-methoxyethyl (meth) acrylate, methoxyethyl (meth) acrylate, and 2-methoxy (meth) acrylate Propyl acrylate, 3-methoxypropyl (meth) acrylate, 2-methoxybutyl (meth) acrylate, 4-methoxybutyl (meth) acrylate, 2-methoxy (meth) acrylate Ethoxyethyl, 3-ethoxypropyl (meth) acrylate, 4-ethoxybutyl (meth) acrylate, and the like.

The adhesive composition may be a homopolymer of an alkyl (meth) acrylate monomer in addition to the acrylic resin adhesive described above. Examples of the (meth) acrylate homopolymer include polymethyl (meth) acrylate, polyethyl (meth) acrylate, poly (meth) acrylate, and polybutyl (meth) acrylate. , Polyoctyl (meth) acrylate, and the like.
Examples of the copolymer containing two or more acrylate units include a methyl (meth) acrylate-ethyl (meth) acrylate copolymer, a methyl (meth) acrylate- (butyl) (meth) acrylate copolymer, A methyl (meth) acrylate-2-hydroxyethyl (meth) acrylate copolymer, a methyl (meth) acrylate-2-hydroxy 3-phenoxypropyl (meth) acrylate copolymer, and the like. Examples of the copolymer of (meth) acrylate and other functional monomers include methyl (meth) acrylate-styrene copolymer, methyl (meth) acrylate-ethylene copolymer, and (meth) acrylate Ester-2-hydroxyethyl (meth) acrylate-styrene copolymer.

Commercially available adhesives may be used, for example, SK Dyne2094, SK Dyne2147, SK Dyne1811L, SK Dyne1442, SK Dyne1435, and SK Dyne1415 (the above are manufactured by Sogoken Chemical Co., Ltd.), Oribain EG-655, and Oribain BPS5896 are preferably used. (The above are manufactured by Toyo Ink Co., Ltd.), etc. (the above are all trade names).

(Anti-reflection layer)
The anti-reflection layer is a layer for preventing reflection on the outermost surface of the transparent screen or reflection from external light. The anti-reflection layer may be laminated on at least one side of the transparent screen, preferably the front side (viewer side), or it may be laminated on both the front side and the rear side. Especially when used as a transparent screen, it is preferably laminated on the front side. The antireflection layer is preferably formed using a resin that does not impair the transparency of the transparent screen or the required optical characteristics. As such a resin, for example, a resin hardened by ultraviolet rays or an electron beam, that is, a radiation-hardening resin, a mixture of a thermoplastic resin and a solvent in a radiation-hardening resin, and a thermosetting resin can be used. Among them, particularly preferred is a radiation-hardening resin. In addition, a fine structure such as an uneven structure, a corner pillar structure, and a microlens structure can be provided on the surface of the antireflection layer depending on the purpose.

The method for forming the anti-reflection layer is not particularly limited, and it can be used: a method of laminating a coating film, directly vapor-depositing a film substrate, or dry coating by sputtering; gravure coating, micro gravure coating, rod Wet coating processes such as coating, sliding die coating, slit die coating, and dip coating.

(Functional layer)
In addition to the above-mentioned layers, the transparent screen may also include various previously known functional layers. Examples of the functional layer include a light absorbing layer including a dye, a colorant, and the like, a corner pillar sheet, a microlens sheet, a Fresnel lens sheet, and a lenticular lens sheet, and a light-scattering layer such as ultraviolet rays and infrared rays.

(Manufacturing method of transparent screen)
The manufacturing method of the transparent screen includes a step of forming a light scattering layer. As for the step of forming the light scattering layer, an extrusion molding method including a kneading step and a film forming step, a casting film forming method, gravure coating, micro gravure coating, rod coating, and sliding die coating can be used. , Slot die coating, dip coating, spray coating methods, injection molding methods, calendering methods, blow molding methods, compression molding methods, casting molding methods and other well-known methods for forming and processing are preferred. An extrusion molding method, an injection molding method, and a coating method are used.

The manufacturing method of the transparent screen may also include the steps of laminating the resin film (light scattering layer) obtained in the film forming step, and then laminating a base material layer, a protective layer, an adhesive layer, and the like. The method of stacking the layers is not particularly limited, and can be performed by a conventionally known method. When the layers are laminated by dry lamination, an adhesive or the like may be used within a range that does not impair the transparency of the transparent screen or the required optical characteristics.

＜ Transparent viewing angle control film ＞
As a transparent viewing angle control film used in an image projection system, a previously known transparent viewing angle control film can be used, as long as it is within the range of the viewing angle control angle to scatter the incident light and transmit the incident light outside the range of the viewing angle control angle. Just fine. The viewing angle control angle can be specified by the angle formed from the base point (the image projection unit or the observer) with respect to the orthogonal plane (perpendicular line) of the transparent viewing angle control film, preferably 10 degrees to 80 degrees, and more preferably 15 degrees Above 70 degrees or less, more preferably 20 degrees or more and 60 degrees or less. Moreover, regarding the transparent viewing angle control film, the parallel light transmittance within the range of the viewing angle control angle is preferably 0% or more and less than 40%, more preferably 0% or more and less than 30%, and the viewing angle control angle thereof The parallel light transmittance outside the range is preferably 60% to 92%, and more preferably 70% to 92%.

Such a viewing angle control film may be a film using a light-shielding structure as described in Patent Documents 4 and 5, which is obtained by alternately laminating a colored or opaque film with a transparent film and cutting along the lamination direction.

Moreover, the light control film such as Patent Document 6 may be a transparent film including a plurality of grooves on the surface of the film and the inside of the grooves is filled with a light-absorbing material.

In the above-mentioned film or light control film obtained by using a light-shielding body structure, the viewing angle control range can be adjusted by the interval between the light-shielding portions and the length in the thickness direction of the light-shielding portion. In addition, although the specular transmittance is determined according to the area ratio occupied by the transmissive portion, if it is necessary to obtain sufficient light shielding performance in the light shielding portion, the area ratio of the light shielding portion needs to be increased. Therefore, the specular transmittance will be reduced, The specular transmittance is inversely proportional.

Further, as the transparent viewing angle control film, a light control plate such as Patent Document 7 may be used that uses two or more kinds of photopolymerizable resins having different refractive indices and has a function of scattering incident light in a specific angle range. According to Patent Document 7, by maintaining a resin composition containing a photopolymerizable oligomer or monomer having a refractive index difference or a mixture thereof in a film form, and irradiating the resin composition with a specific direction to harden it, A light control film having a function of scattering only a specific range of light can be obtained. The obtained film exhibits anisotropy with respect to the long axis and short axis directions of the ultraviolet light source, and only when the film-like hardened material is rotated with the long axis direction of the light source as an axis, light in a specific angular range is scattered. That is, it is considered that the obtained film exists in a state of being oriented in a direction having regions with different refractive indexes, and the angle of view control is obtained by repeatedly scattering the light incident from a specific angle range at the boundary of the regions with different refractive indexes. effect. In this method, the two or more photopolymerizable resins used are non-absorptive and transparent only because of the difference in refractive index. Therefore, they have the advantage of obtaining a very high specular transmittance. Therefore, when UV light is incident upon curing, Since it becomes a substantially transparent body in the direction, it is particularly suitable for use as a transparent viewing angle control film in the present invention.

As the transparent viewing angle control film, a commercially available transparent viewing angle control film can be used, and for example, a Wincos visual control film (Y-2555) manufactured by Lintec Corporation (viewing angle control angle: 25 ° to 55 °) can be used.

＜ Laminated body ＞
The laminated body used in the image projection system has a transparent screen and a transparent viewing angle control film. The laminated body may be in a form in which a transparent screen is directly formed on the viewing angle control film, or may be in a form in which a viewing angle control film is directly formed on the transparent screen.

The laminated body may include a transparent layer preferably containing a transparent resin between the transparent screen and the viewing angle control film within a range that does not impair the performance of the image projection system. For example, the laminated body may be in a form in which a transparent screen and a viewing angle control film are bonded together with an adhesive, an adhesive, or an adhesive resin.

Regarding the laminated body, the parallel light transmittance outside the range of the viewing angle control angle is preferably 60% to 98%, more preferably 65% to 96%, even more preferably 70% to 94%, and even more preferably 75% to 92%. As long as the parallel light transmittance of the transparent screen is within the above range, the transparency is high, and the visibility of transmission can be further improved. Furthermore, in the present invention, the parallel light transmittance of the transparent screen can be measured using a turbidimeter (manufactured by Nippon Denshoku Industries Co., Ltd., product number: NDH-5000) in accordance with JIS-K-7361 and JIS-K-7136. Determination.

Regarding the laminated body, the image sharpness is preferably 65% or more, more preferably 70% or more and 98% or less, still more preferably 75% or more and 97% or less, and still more preferably 80% or more and 96% or less. As long as the image clarity of the transparent screen is within the above range, the image visible through the transparent screen will become extremely clear. In addition, in the present invention, the image sharpness is a value of image sharpness (%) when measured at an optical comb width of 0.125 mm in accordance with JIS K7374.

<Vehicle components>
In the image projection system of the present invention, a vehicle component provided with the transparent screen described above can also be used. The vehicle member may further include the transparent viewing angle control film. Examples of the vehicle member include a front window glass and a side window glass. The vehicle component is provided with the transparent screen described above, so that a clear image can be displayed on the vehicle component without a separate screen.

<Building components>
In the image projection system of the present invention, it is also possible to use a building component provided with the above-mentioned transparent screen. The building member may further include the transparent viewing angle control film. Examples of building members include window glass of houses, glass walls of convenience stores, and roadside stores. The building component is provided with the transparent screen described above, and a clear image can be displayed on the building component without a separate screen.
[Example]

＜ Observation method ＞
The equipment configuration and the observation conditions of the projected image in the examples and comparative examples are as follows.

＜ Case of fixed setting ＞
The WX450ST manufactured by Canon Inc. was used as the image projection unit, and the lens center was arranged at a height of 10 cm higher than the configuration table.
The test bodies of the transparent screens, transparent viewing angle control films, or laminates described in the examples and comparative examples were adhered to an acrylic resin plate with a thickness of 2 mm by an adhesive material at a distance of 13.5 cm from the front end of the lens of the image projection unit. It is placed on the table in a vertical manner. At this time, the image light from the projection image unit was imaged on the test body at a size of about 14 cm in length and 22 cm in width. Adjust the height of the test body in such a way that the lower end of the image mapped to the test body is 20 cm away from the table surface. In this state, observe the test body from the horizontal position on the front side and the rear side, and visually observe the mapping situation and background of the image. Also, take photos at the same time. Furthermore, by visually observing the test body and a wall located approximately 150 cm behind the test body from the front side, a picture was taken of the state of light leakage from the test body.

＜ Production of image projection system ＞
[Example 1]
First, polyethylene terephthalate (PET) particles (manufactured by Bell Polyester Co., Ltd. model IFG8L) and flaky aluminum fine particles A (light-reflective fine particles, primary particles) of 0.012% by mass based on the PET particles were prepared. (The average diameter is 1 μm, the aspect ratio is 300, and the specular reflectance is 62.8%). Mix in a roller mixer for 30 minutes to obtain PET particles with flake aluminum uniformly adhered to the surface. The obtained granules were supplied to a hopper of a biaxial kneading extruder equipped with a wire mold, and a masterbatch with thin sheet aluminum was obtained at an extrusion temperature of 250 ° C. The obtained master batch and PET pellets (model IFG8L) were uniformly mixed at a ratio of 1: 2, and then put into a hopper of a biaxial extruder equipped with a T die, and extruded at an extrusion temperature of 250 ° C to obtain a thickness of 75 μm. Film to get a transparent screen. The optical characteristics of the transparent screen were measured. As a result, the haze value of the transparent screen was 3.9%, the total light transmittance was 86%, and the image clarity was 88%. Next, a Wincos visual control film (Y-2555) (viewing angle control angle: 25 ° to 55 °) manufactured by Lintec Co., Ltd. was prepared as a transparent viewing angle control film. Then, a transparent screen and a transparent viewing angle control film were laminated to obtain a laminated body A. The optical characteristics of the multilayer body A were measured. As a result, the parallel light transmittance outside the range of the viewing angle control angle was 80%, and the image clarity was 85%.

After arranging the laminated body A obtained as described above, the transparent screen side of the laminated body A is set to the observer side, and an image projection unit (manufactured by Canon Inc., WX450ST) is arranged on the front side to produce an image projection system (first embodiment) . Then, the image light from the image projection unit is directed toward the transparent screen and is projected in a range of the viewing angle control angle (25 ° to 55 °) of the transparent viewing angle control film. As a result, the light passes through the transparent viewing angle control film. Scattering occurred, and the image was not mapped to the wall about 150 cm away from the rear side of the self-laminated body A. Therefore, it was confirmed that the light passing through the transparent screen did not reach objects other than the transparent screen to form an image, and did not hinder comfortable visual recognition. In addition, when the laminated body A was observed horizontally, a clear image was formed on the laminated body A, and since the visibility of the laminated body A was high, the background wall could be clearly recognized. The results of photographing are shown in FIG. 6.
Then, an image projection unit is arranged on the rear side, and the laminated body A is observed horizontally. As a result, the laminated body A has a clear image imaging, and because the visibility of the laminated body A is high, the background wall can be clearly recognized. The results of photographing are shown in FIG. 7.

[Example 2]
After arranging the laminated body A obtained in Example 1, the first transparent viewing angle control film side of the laminated body A is set as the observer side, and an image projection unit (manufactured by Canon (Stock), WX450ST) is arranged on the front side to produce an image projection System (second embodiment). Then, the image light from the image projection unit was directed toward the transparent viewing angle control film and projected within the range of the viewing angle control angle (25 ° to 55 °) of the transparent viewing angle control film, and the result was diffused through the transparent viewing angle control film The scattered image light reaches the transparent screen, and the light passing through the transparent screen is scattered. The image is not mapped to the wall about 150 cm away from the back side of the laminated body A. Therefore, it was confirmed that the light passing through the transparent screen did not reach objects other than the transparent screen to form an image, and did not hinder comfortable visual recognition. In addition, the laminated body A was observed horizontally, and as a result, a clear image was formed on the laminated body A. Since the visibility of the laminated body A is high, the background wall can be clearly recognized. The results of photographing are shown in FIG. 8.
Then, an image projection unit is arranged on the rear side, and the laminated body A is observed horizontally. As a result, the laminated body A has a clear image imaging. Because the visibility of the laminated body A is high, the background wall can be clearly recognized. The results of photographing are shown in FIG. 9.
Furthermore, it can be seen that the brightness when the image imaged on the laminated body A in Example 2 is observed horizontally is higher than the brightness on the imaged image on the laminated body A in Example 1 on both the rear side and the front side.

[Comparative Example 1]
An image projection system was produced in the same manner as in Example 1 except that the above-mentioned transparent screen was used directly instead of the laminated body A. Then, with respect to the image projection unit, the image light is projected from the front side to the transparent screen, and it is confirmed that the transmitted light is also imaged on the wall located at a distance of about 150 cm from the rear side, and the light transmitted through the transparent screen reaches the object outside the transparent screen to be imaged , Hinder the recognition of comfort. In addition, when the transparent screen is viewed horizontally, a clear image is formed on the transparent screen. As the transparency of the transparent screen is high, the background wall can be clearly observed.
Then, an image projection unit is arranged on the rear side and the transparent screen is observed horizontally. As a result, a clear image is formed on the transparent screen. Because the transparency of the transparent screen is high, the background wall can be clearly observed.
Furthermore, it was found that when the image projection unit was observed through a transparent screen, the light source of the so-called bright spot image projection unit was observed very glaringly, which hindered the appreciation of the image.

[Comparative Example 2]
An image projection system was produced in the same manner as in Example 2 except that the transparent viewing angle control film was used directly instead of the laminated body A. Then, project the image light toward the transparent viewing angle control film from the image projection unit and project within the range of the viewing angle control angle (25 ° to 55 °) of the transparent viewing angle control film, and confirm that the transmitted light will not be placed in the The imaging of the wall at a distance of about 150 cm from the rear side will not cause light that passes through the transparent viewing angle control film to reach objects other than the transparent viewing angle control film, and will not hinder comfortable visual recognition. In addition, the transparent viewing angle control film was observed horizontally. As a result, although the background wall could be clearly recognized, the image light from the image projection unit was not clearly imaged on the transparent viewing angle control film.
Then, an image projection unit is arranged on the rear side, and the transparent viewing angle control film is observed horizontally. As a result, although the background wall can be clearly recognized, the image light from the image projection unit is not clearly imaged on the transparent viewing angle control film.

11‧‧‧ transparent screen

12‧‧‧ transparent viewing angle control film

13‧‧‧Image projection unit

14‧‧‧ Range of projection angle of image light

15‧‧‧Range of viewing angle control

16‧‧‧ Orthographic plane (perpendicular line) of transparent viewing angle control film

18‧‧‧Part of the angle control range

19‧‧‧Part of the angle of view control

21‧‧‧ transparent screen

22‧‧‧Transparent viewing angle control film

23‧‧‧Image projection unit

24‧‧‧ Range of projection angle of image light

25‧‧‧Viewing angle control range

26‧‧‧ Orthographic plane (perpendicular line) of transparent viewing angle control film

31‧‧‧ transparent screen

32‧‧‧Transparent viewing angle control film

33‧‧‧Image projection unit

34‧‧‧ Range of projection angle of image light

35‧‧‧Viewing angle control range

36‧‧‧ Orthographic plane (perpendicular line) of transparent viewing angle control film

38‧‧‧ transparent layer

41‧‧‧ transparent screen

42‧‧‧Transparent viewing angle control film

43‧‧‧Image projection unit

44‧‧‧ Range of projection angle of image light

45‧‧‧Viewing angle control range

45u‧‧‧The upper limit value of the angle of view control

46‧‧‧ Orthographic plane (perpendicular line) of transparent viewing angle control film

47‧‧‧ observer

48‧‧‧ Orthographic plane (perpendicular line) of transparent viewing angle control film

49‧‧‧Viewing angle range

49l‧‧‧ lower limit of observation angle range

51‧‧‧ transparent screen

52‧‧‧Transparent viewing angle control film

53‧‧‧Image projection unit

54‧‧‧ Range of projection angle of image light

55‧‧‧Viewing angle control range

55l‧‧‧ Lower limit of the range of viewing angle

56‧‧‧ Orthographic plane (perpendicular line) of transparent viewing angle control film

57‧‧‧ observer

58‧‧‧ Orthographic plane (perpendicular line) of transparent viewing angle control film

59‧‧‧Viewing angle range

59u‧‧‧The upper limit of the viewing angle range

α‧‧‧ Angle formed with respect to the orthogonal plane (perpendicular line) of the transparent viewing angle control film

β‧‧‧ Angle (upper side) with respect to the orthogonal plane (perpendicular line) of the transparent viewing angle control film

γ‧‧‧ Angle (lower side) with respect to the orthogonal plane (perpendicular line) of the transparent viewing angle control film

FIG. 1 is a conceptual diagram showing a projection image system according to a first embodiment of the present invention.

FIG. 2 is a conceptual diagram showing a projection image system according to a second embodiment of the present invention.

FIG. 3 is a conceptual diagram showing a projection image system according to a second embodiment of the present invention.

FIG. 4 is a conceptual diagram showing a viewing angle between a projection image system and an observer in a second embodiment of the present invention.

FIG. 5 is a conceptual diagram showing an observation angle between a projection image system and an observer in a second embodiment of the present invention.

FIG. 6 is a diagram showing the results of observation from the front side (the same side as the image projection unit) of the transparent screen in the projection image system of Example 1. FIG.

FIG. 7 is a diagram showing the results of observation from the rear side (opposite to the image projection unit) of the transparent screen in the projection image system of Example 1. FIG.

FIG. 8 is a diagram showing the results of observation from the front side (the same side as the image projection unit) of the transparent screen in the projection image system of Example 2. FIG.

FIG. 9 is a diagram showing a result of observation from a rear side of the transparent screen (the side opposite to the image projection unit) in the projection image system of Embodiment 2. FIG.

FIG. 10 is a diagram showing the results of observation from the front side (the same side as the image projection unit) of the transparent screen in the projection image system of Comparative Example 1. FIG.

11 is a diagram showing the results of observation from the front side (the same side as the image projection unit) of the viewing angle control film in the projection image system of Comparative Example 2. FIG.

Claims (10)

An image projection system includes a transparent screen, a transparent viewing angle control film disposed on one side of the transparent screen, and an image projection unit disposed on the transparent screen side, and The image projection unit is configured such that the projection angle of the image light from the image projection unit is within the range of the viewing angle control angle of the transparent viewing angle control film, The image light is imaged on the transparent screen. The transparent viewing angle control film scatters image light transmitted through the transparent screen. An image projection system includes a transparent screen, a transparent viewing angle control film disposed on one surface side of the transparent screen, and an image projection unit disposed on the transparent viewing angle control film side, and The image projection unit is configured such that the projection angle of the image light from the image projection unit is within the range of the viewing angle control angle of the transparent viewing angle control film, Scattering the image light by the transparent viewing angle control film, The image light passing through the transparent viewing angle control film is imaged on the transparent screen. For example, the image projection system of claim 1 or 2, wherein the viewing angle control angle of the transparent viewing angle control film is 10 degrees or more and 80 degrees or less. If the image projection system of any one of claims 1 to 3, wherein the lower limit value of the observer's viewing angle range is when the image projection unit is positioned above the observer, the lower limit value is greater than the transparent viewing angle The upper limit of the range of the viewing angle of the control film. If the image projection system of any one of claims 1 to 3, wherein the upper limit value of the observation angle range of the observer is in a case where the image projection unit is located below the observer, the upper limit value is smaller than the transparent viewing angle The lower limit of the range of the viewing angle of the control film. The image projection system according to any one of claims 1 to 5, wherein the transparent light-transmitting control film has a parallel light transmittance within a range of the angle-of-view control of 0% to 40%, and the range of the angle of control Outside parallel light transmittance is 60% to 92%. The image projection system according to any one of claims 1 to 6, wherein the transparent screen and the transparent viewing angle control film constitute a laminated body. The image projection system according to claim 7, wherein the laminated body includes a transparent layer between the transparent screen and the transparent viewing angle control film. For example, the image projection system of any one of claims 1 to 8, wherein the haze value of the transparent screen is less than 35%. The image projection system according to any one of claims 1 to 9, wherein the transparent screen includes light reflective particles.