JP2017173440A - Reflection screen and video display system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reflection screen and a video display system which suppress glare of a video and can improve front luminance.SOLUTION: A reflection screen 20 is a reflection screen which reflects video light projected from a video source to display the video light on a screen, has a lens surface 232 and a non-lens surface 233, has a lens layer 23 where a plurality of unit lenses 231 that are convex on the rear side are arrayed, a reflection layer 22 which is formed from a resin containing a plurality of scaly metal thin films 22a on at least a part of the lens surface 232 and reflects light, and a light diffusion layer 241 which is provided on the video source side of the reflection layer 22 and diffuses light, a shortest distance p between the reflection layer 22 and the light diffusion layer 241 in a thickness direction of the reflection screen 20 satisfies a relationship of p≥450 μm, a value S of scintillation satisfies a relationship of S≤7%, and a peak gain PG satisfies a relationship of PG≥0.8.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a reflection screen and an image display system for displaying an image by reflecting projected image light.

  Conventionally, reflective screens having various configurations have been developed and used in video display systems. In recent years, short focus type video projection devices (projectors) that project a video light at a relatively large projection angle from a close distance to a reflective screen to realize a large screen display have been widely used. Reflective screens and the like have also been developed for satisfactorily displaying video light projected by a short focus type video projector.

The short focus type image projection apparatus can project image light at a larger projection angle than the conventional image source from above or below the reflection screen, and the distance in the depth direction between the image projection apparatus and the reflection screen. Therefore, it is possible to contribute to space saving of an image display system using a reflective screen.
A reflection screen used in such a video projection apparatus has a light diffusing layer for diffusing light in order to give a viewing angle provided on a surface on the viewer side of a lens layer (for example, Patent Document 1). ).
In order to improve the front luminance, such a reflective screen can be considered to reduce the amount of the diffusing agent contained in the light diffusing layer. However, if the diffusing agent is reduced, the diffusing agent in the light diffusing layer is considered. In some cases, the position of the image is likely to be localized, causing glare (scintillation) in the image.

JP 2013-130837 A

  An object of the present invention is to provide a reflective screen and a video display system that can suppress the occurrence of video glare and improve the front luminance.

The present invention solves the above problems by the following means. In addition, in order to make an understanding easy, although the code | symbol corresponding to embodiment of this invention is attached | subjected and demonstrated, it is not limited to this.
The first invention is a reflective screen (20) for reflecting video light projected from a video source and displaying it on a screen, comprising a lens surface (232) and a non-lens surface (233), and convex on the back side. A lens layer (23) in which a plurality of unit lenses (231) are arranged and a resin containing a plurality of scale-like metal thin films (22a) on at least a part of the lens surface, and reflects light And a light diffusion layer (241) for diffusing light, provided on the image source side of the reflection layer, and the reflection layer and the light diffusion layer in the thickness direction of the reflection screen, The reflection screen is characterized in that the shortest distance p is p ≧ 450 μm, the scintillation value S satisfies S ≦ 7%, and the peak gain PG satisfies PG ≧ 0.8.
A second invention is the reflecting screen according to the first invention, wherein the shortest distance p is p ≦ 1370 μm.
According to a third aspect of the present invention, in the reflective screen (20) of the first or second aspect, a colored layer that adjusts a light transmittance between the light diffusion layer (241) and the reflective layer (22). (242) is formed.
A fourth invention is a video display system (1) comprising any of the reflective screens (20) from the first invention to the third invention, and a video source (LS) for projecting video light onto the reflective screen. ).

  ADVANTAGE OF THE INVENTION According to this invention, it can suppress that the glare of a video arises and can improve front luminance.

It is a figure explaining the video display system of an embodiment. It is a figure explaining the layer structure of the reflective screen of embodiment. It is a figure explaining the detail of the lens layer and reflection layer of embodiment. It is an enlarged photograph which shows the cross section of the reflection layer formed in the lens layer of embodiment. It is a figure explaining an example of the manufacturing method of the reflective screen of embodiment. It is the figure which put together the evaluation result of the glare of an image of the reflective screen of each Example and each comparative example, and a peak gain. It is a figure explaining the half value angle in luminance distribution. It is a figure which shows the detail of the lens layer of a reflective screen of a deformation | transformation form, and a reflective layer.

Embodiments of the present invention will be described below with reference to the drawings.
In addition, each figure shown below including FIG. 1 is the figure shown typically, and the magnitude | size and shape of each part are exaggerated suitably for easy understanding.
In addition, words such as plate and sheet are used, but these are generally used in the order of thickness, plate, sheet, and film in order of increasing thickness. I use it. However, there is no technical meaning in such proper use, so these terms can be replaced as appropriate.
Furthermore, numerical values such as dimensions and material names of each member described in the present specification are examples of the embodiment, and the present invention is not limited thereto, and may be appropriately selected and used.

In this specification, terms that specify shape and geometric conditions, for example, terms such as parallel and orthogonal, are strictly meanings, have similar optical functions, and can be regarded as parallel and orthogonal It also includes a state having an error of.
In this specification, the sheet surface (plate surface, film surface) is the planar direction of the sheet (plate, film) when viewed as the entire sheet (plate, film) in each sheet (plate, film). It is assumed that the surface to be

(Embodiment)
FIG. 1 is a diagram illustrating a video display system 1 according to the present embodiment. FIG. 1A is a perspective view of the video display system 1, and FIG. 1B is a side view of the video display system 1.
The video display system 1 includes a reflective screen unit 10 including a reflective screen 20, a video source LS, and the like. In the video display system 1 of the present embodiment, the reflective screen 20 reflects the video light L projected from the video source LS, and displays the video on the screen.
The video display system 1 can be used as, for example, a front projection television system that projects video light L from a video source LS.

The video source LS is a video light projection device that projects the video light L onto the reflection screen 20. The video source LS of this embodiment is a general-purpose short focus projector. When the image source LS is in use and the screen of the reflection screen 20 is viewed from the normal direction (normal direction of the screen surface), the image source LS is the center in the horizontal direction of the screen of the reflection screen 20 and the image of the reflection screen 20 It is arranged at a position below the (display area).
The screen surface refers to a surface that is the planar direction of the reflective screen 20 when viewed as the entire reflective screen 20.
The video source LS can project the video light L from a position where the distance from the reflective screen 20 in a direction orthogonal to the screen of the reflective screen 20 (thickness direction of the reflective screen 20) is much closer than that of a conventional general-purpose projector. . That is, the image source LS has a shorter projection distance to the reflection screen 20 and a larger incident angle of the image light L with respect to the screen surface of the reflection screen 20 than a conventional general-purpose projector.

The reflection screen 20 is a screen that displays the image by reflecting the image light L projected by the image source LS toward the observer O side. In the use state, the observation screen of the reflection screen 20 has a substantially rectangular shape with the long side direction being the horizontal direction of the screen when viewed from the observer O side.
In the following description, the screen vertical direction, the screen horizontal direction, and the thickness direction are the screen vertical direction (vertical direction), the screen horizontal direction (horizontal direction), and thickness when the reflective screen 20 is used unless otherwise specified. The direction (depth direction) is assumed.
The reflective screen 20 has a large screen (display area) having a diagonal size of 100 inches or 120 inches, for example.

  The video display system 1 of the present embodiment includes a video source LS that is a short focus type projector, and a reflective screen 20 that displays video by reflecting video light projected from the video source LS. However, the present invention is not limited to this, and the image source LS is a conventional general-purpose projector having a long projection distance and a small image light projection angle (that is, an incident angle of the image light on the screen), and the reflection screen 20 is such a projector. It may correspond to the video source LS.

  As shown in FIG. 1, the reflective screen unit 10 includes a reflective screen 20, a flat support plate 30 disposed on the back side thereof, and a bonding layer 40. The reflection screen 20 and the support plate 30 are integrally bonded via a bonding layer 40.

The support plate 30 is not particularly limited as long as it is a member having high rigidity. For example, a metal plate material such as aluminum or a resin plate material such as acrylic resin is preferably used. . In addition, a metal plate material (so-called honeycomb panel) that reduces the weight of the entire plate material by providing a honeycomb structure formed of a thin plate of aluminum or the like on the front and back surfaces and a thin plate of aluminum or the like as an inner core material. Etc. may be used. Moreover, it is preferable that the support plate 30 is a member which does not have a light transmittance from a viewpoint of preventing the reflection of external light, the contrast fall by external light, etc.
The thickness of the support plate 30 is preferably 0.2 to 5.0 mm, more preferably 1.0 to 3.0 mm. If the thickness is less than 0.2 mm, sufficient rigidity to support flatness is insufficient, and if the thickness is more than 5.0 mm, the weight of the support plate 30 becomes heavy.
In many cases, the reflective screen 20 is thin and does not have sufficient rigidity to maintain flatness by itself. For this reason, the reflection screen 20 maintains the flatness of the screen by being integrally joined to the support plate 30.

  The bonding layer 40 is a layer having a function of bonding the reflective screen 20 and the support plate 30 together. The bonding layer 40 is formed of a pressure sensitive adhesive, an adhesive, or the like.

FIG. 2 is a diagram illustrating the layer configuration of the reflective screen 20 of the present embodiment.
In FIG. 2, it passes through a point A (see FIGS. 1A and 1B) that is the geometric center (center of the screen) of the observation screen (display area) of the reflection screen 20, and is parallel to the vertical direction of the screen. FIG. 2 shows an enlarged part of a cross section perpendicular to the screen surface (parallel to the thickness direction).
As shown in FIG. 2, the reflective screen 20 includes a surface layer 25, a base material layer 24, a lens layer 23, and a reflective layer 22 in order from the image source side (observer side) in the thickness direction.
The base material layer 24 is a sheet-like member serving as a base material for forming the lens layer 23. A surface layer 25 is integrally formed on the image source side of the base material layer 24, and a lens layer 23 is integrally formed on the back side (back side).
The base material layer 24 has a light diffusion layer 241 containing a diffusing agent and a colored layer 242 containing a coloring material such as a pigment or a dye. The base material layer 24 of this embodiment is formed by integrally laminating a light diffusion layer 241 and a colored layer 242 by coextrusion molding.
In the present embodiment, as shown in FIG. 2, in the base material layer 24, the light diffusion layer 241 is on the image source side and the colored layer 242 is on the back side, that is, the image source side surface of the lens layer 23. A colored layer and a light diffusion layer are sequentially laminated.

The light diffusion layer 241 is a layer containing a light-transmitting resin as a base material and a diffusing agent that diffuses light. The light diffusion layer 241 has a function of widening the viewing angle and improving the in-plane uniformity of brightness.
Examples of the resin used as the base material of the light diffusion layer 241 include PET (polyethylene terephthalate) resin, PC (polycarbonate) resin, MS (methyl methacrylate / styrene) resin, MBS (methyl methacrylate / butadiene / styrene) resin, TAC ( Triacetyl cellulose) resin, PEN (polyethylene naphthalate) resin, acrylic resin and the like are preferably used.

As the diffusing agent contained in the light diffusion layer 241, particles made of a resin such as an acrylic resin, an epoxy resin, or the like, an inorganic particle, or the like is preferably used. Note that the diffusing agent may be a combination of an inorganic diffusing agent and an organic diffusing agent. This diffusing agent is preferably substantially spherical and has an average particle diameter of about 1 to 50 μm. Moreover, it is preferable that the range of the particle size of the diffusing agent suitable for use is 5 to 30 μm.
The thickness of the light diffusion layer 241 is preferably about 100 to 2000 μm, although it depends on the screen size of the reflection screen 20 and the like. The light diffusion layer 241 preferably has a haze value in the range of 85 to 99%.

  Here, a reflection screen (hereinafter referred to as a conventional reflection screen) that is often used conventionally is provided with a light diffusion layer and a colored layer sequentially on the image source side of the lens layer from the viewpoint of enhancing the blackness of the screen. The reflection layer and the light diffusion layer were close to each other in the thickness direction of the screen. In this configuration, it is conceivable to reduce the diffusing agent contained in the light diffusing layer in order to improve the front luminance of the reflective screen. However, if the diffusing agent is reduced, the diffusion agent in the light diffusing layer is reduced. In some cases, the position is localized, and the image is glazed (scintillation), and a good image cannot be displayed.

  Therefore, the reflective screen 20 of this embodiment is provided with the colored layer 242 and the light diffusion layer 241 sequentially on the image source side of the lens layer 23, and the distance between the light diffusion layer 241 and the reflection layer 22 in the thickness direction is a predetermined distance. Just separated. As a result, the reflective screen 20 of the present embodiment improves the front luminance and generates glare in the image even when the position of the diffusing agent in the light diffusion layer is localized as described above. Can be suppressed.

Here, as for the reflective screen 20, it is desirable that the shortest distance p between the light diffusion layer 241 and the reflective layer 22 in the thickness direction of the screen is 450 ≦ p ≦ 1370. The shortest distance p is a distance from a point v serving as a valley bottom between the unit lenses 231 on which the reflection layer 22 is formed in the normal direction (thickness direction) of the screen surface to the back side surface of the light diffusion layer 241 ( (See FIG. 2).
If the shortest distance p between the light diffusing layer and the reflecting layer in the thickness direction is less than 450 μm, the light diffusing layer and the reflecting layer are too close to each other, and the effect of suppressing image glare (scintillation) is reduced. This is not desirable. When the shortest distance p is larger than 1370 μm, the thickness of the reflective screen becomes thick, and the weight of the reflective screen increases too much, which is not desirable.

In addition, the reflective screen 20 of the present embodiment desirably has a peak gain PG of PG ≧ 0.8 from the viewpoint of ensuring a sufficient front luminance and displaying a bright and good image even in a bright room environment. .
In addition, the reflection screen 20 of the present embodiment desirably has a scintillation value S of S ≦ 7.0% from the viewpoint of improving the front luminance and suppressing the occurrence of image glare.
Here, the scintillation value S is a value that serves as an index for evaluating video glare, and is a value obtained by the following equation (1).

Formula (1) S [%] = 100 × σ [cd / m ² ] / M [cd / m ² ]

Here, σ in equation (1) is a range of 40 mm in the vertical direction of the screen about the geometric center A of the reflective screen 20 and 60 mm in the horizontal direction of the screen, and a pitch of 255 μm in the vertical direction of the screen and the horizontal direction of the screen. This is the value of the standard deviation of the luminance at each measurement point when a white image is displayed on this reflection screen with the intersection of each line segment as the measurement point. M represents an average value of each luminance at the above measurement points. The luminance at each measurement point is a color luminance meter (Prometric PM series, manufactured by Radiant Imaging) located at a position 1.0 m away from the geometric center of the reflective screen 20 toward the observer side in the normal direction of the screen surface. In addition, the image source (LV-8235US manufactured by Canon Inc.) is positioned 650 mm downward from the geometric center A on the viewer side of the reflective screen and 450 mm away from the sheet surface to the viewer side in the normal direction. Measured by placing.
If the value S of the scintillation of the reflective screen is larger than 7.0, it is not desirable because the glare of the video remarkably occurs.

The colored layer 242 is a layer colored with a dark colorant such as black so as to have a predetermined light transmittance. The colored layer 242 has a function of improving the contrast of an image by absorbing unnecessary external light such as illumination light incident on the reflective screen 20 and reducing the black luminance of the displayed image.
As the colorant of the colored layer 242, a dark dye such as gray or black, a pigment, a metal salt such as carbon black, graphite, black iron oxide, or the like is preferably used.
As a resin which is a base material of the coloring layer 242, a PET resin, a PC resin, an MS resin, an MBS resin, a TAC resin, a PEN resin, an acrylic resin, or the like can be used.
The colored layer 242 preferably has a thickness of about 430 to 1350 μm, although it depends on the screen size and the like of the reflective screen 20.

FIG. 3 is a diagram illustrating details of the lens layer 23 and the reflective layer 22 of the present embodiment.
FIG. 3A shows a state in which the lens layer 23 is observed from the front side on the back side, and the reflection layer 22 is omitted for easy understanding. FIG. 3B shows an enlarged part of the cross section shown in FIG. FIG. 3C shows an enlarged perspective view of the lens layer on which the reflective layer is formed. In FIG. 3B and FIG. 3C, the base material layer 24 and the surface layer 25 located on the image source side of the lens layer 23 are omitted for easy understanding.

The lens layer 23 is a light-transmitting layer provided on the back side of the base material layer 24, and a plurality of unit lenses 231 are arranged concentrically around the point C as shown in FIG. The circular Fresnel lens shape is provided on the back side surface. In this circular Fresnel lens shape, the point C which is the optical center (Fresnel center) is outside the area of the screen (display area) of the reflective screen 20 and is located below the reflective screen 20.
In the present embodiment, the lens layer 23 will be described by taking an example in which a circular Fresnel lens shape is provided on the surface on the back side. However, the present invention is not limited to this, and the unit lenses 231 are arranged in the screen vertical direction along the screen surface. It is good also as a form which has the made linear Fresnel lens shape.

2 and 3B, the unit lens 231 is parallel to the direction orthogonal to the screen surface (thickness direction of the reflection screen 20) and is a cross section in a cross section parallel to the arrangement direction of the unit lenses 231. The shape is a substantially triangular shape.
The unit lens 231 is convex on the back side, and includes a lens surface 232 and a non-lens surface 233 that faces the lens surface 232.
In the present embodiment, in the usage state of the reflection screen 20, the unit lens 231 has the lens surface 232 positioned above the non-lens surface 233 across the vertex t.

As shown in FIG. 3B, the angle formed by the lens surface 232 of the unit lens 231 with a surface parallel to the screen surface is α. Further, the angle formed by the non-lens surface 233 and the surface parallel to the screen surface is β (β> α). Furthermore, the arrangement pitch of the unit lenses 231 is P, and the lens height of the unit lenses 231 (the dimension from the apex t in the thickness direction of the screen to the point v that becomes the valley bottom between the unit lenses 231) is h.
In order to facilitate understanding, in FIG. 2 and the like, the arrangement pitch P and the angles α and β of the unit lenses 231 are shown to be constant in the arrangement direction of the unit lenses 231. However, the unit lenses 231 according to the present embodiment have a constant arrangement pitch P or the like, but gradually become larger as the angle α becomes farther from the point C that becomes the Fresnel center in the arrangement direction of the unit lenses 231. Accordingly, the lens height h also fluctuates. The unit lenses 231 of the present embodiment are formed so that the arrangement pitch P is in the range of 50 to 200 μm, the lens height h is in the range of 0.5 to 60 μm, and the angle α of the lens surface 232 is 0.5 to. The angle β of the non-lens surface 233 is formed in the range of 45 to 90 °.
The arrangement pitch P is not limited to this, and the arrangement pitch P may be changed gradually along the arrangement direction of the unit lenses 231. The size of the pixel of the video source LS that projects the video light L, the video source, and the like The LS projection angle (the incident angle of the image light on the screen surface of the reflection screen 20), the screen size of the reflection screen 20, the refractive index of each layer, and the like can be changed as appropriate.

The lens layer 23 is integrally formed on the back side surface of the base material layer 24 (in this embodiment, the light diffusion layer 241 side) by an ultraviolet curable resin such as urethane acrylate or epoxy acrylate. The lens layer 23 may be formed of another ionizing radiation curable resin such as an electron beam curable resin.
The lens layer 23 may use a thermoplastic resin, or may be formed by a press molding method or the like according to the Fresnel lens shape of the lens layer 23. In the case of such a lens layer 23, the base material layer 24 (light diffusion layer 241) or the like may be laminated on the image source side via a bonding layer (not shown) or the like. In addition, when an extrusion molding method is possible, the lens layer 23 and the base material layer 24 may be molded in an integrally laminated state.

FIG. 4 is an enlarged photograph showing a cross section of the reflective layer formed on the lens layer of the embodiment.
The reflection layer 22 is a layer having an action of reflecting light. The reflection layer 22 has a sufficient thickness for reflecting light, and is formed on at least a part of the lens surface 232 of the unit lens 231.
The reflection layer 22 of this embodiment is formed on the lens surface 232 and the non-lens surface 233 as shown in FIG. 2 and FIG. Specifically, the reflection layer 22 covers the back side of the lens layer 23 and is formed so as to fill a boundary between the unit lenses 231 that are convex on the back side, that is, a point v that becomes a valley bottom. Thereby, the reflective layer 22 can make the unevenness | corrugation of the back side of a lens layer substantially flat, and can stick the support plate 30 more stably via the joining layer 40. FIG.
FIG. 4 is a cross-sectional view at a position 1100 mm from the point C serving as the Fresnel center. The reflection layer 22 shown in this figure has a valley bottom between the unit lenses 231 with respect to the lens height h = 20 μm of the unit lens 231. The thickness in the thickness direction of the lens layer 23 at the point v is 24 μm, and the support plate 30 can be stably attached to the back side of the reflective layer 22.
Here, as described above, the lens height h of the unit lenses 231 varies as the distance from the point C that becomes the Fresnel center in the arrangement direction of the unit lenses 231, but at the point v that becomes the valley bottom between the unit lenses 231. The thickness of the reflective layer 22 in the thickness direction of the lens layer 23 is formed with a dimension within a range of 10 to 120% with respect to the lens height h of each unit lens 231 in order to achieve the above-described effect more effectively. It is preferable.

The reflective layer 22 is formed by spray coating the lens surface 232 with a paint (resin) containing a scaly metal thin film 22 a having high light reflectivity such as aluminum on the lens surface 232. As shown in FIG. 4, the reflective layer 22 has a surface perpendicular to the thickness direction of the scale-like metal thin film 22 a disposed substantially parallel to the lens surface 232, and the image light L incident on the lens surface 232 Can be appropriately reflected toward the viewer. Here, “substantially parallel” means not only the case where the surface perpendicular to the thickness direction of the metal thin film 22a is completely parallel to the lens surface 232 but also the inclination with respect to the lens surface 232 is in the range of −10 ° to + 10 °. It includes things that include some cases. Further, the scale-like metal thin film 22a means that the shape (outer shape) viewed from the thickness direction of the metal thin film 22a is a scale-like shape. The scale-like shape is not only a scale-like shape but also an elliptical shape or , Including a circular shape, a polygonal shape, and an irregular shape obtained by pulverizing a thin film.
Here, as the property classification of the scale-like metal thin film, there are a leafing type, a non-leafing type, a resin coating type, etc., which are each characterized by metallic luster, concealment, adhesion, orientation, etc. For example, a metallic luster is important, but a resin coating type is preferable in consideration of adhesion, orientation, and the like.

In order to maintain and improve the reflection efficiency of the image light and prevent the back side of the reflection layer 22 from being seen through, the metal thin film 22a is laminated on the lens surface of each of the plurality of unit lenses by an average of 8 layers or more. It is desirable that The reflective layer 22 provided with eight or more metal thin films 22 a described above may be provided on some lens surfaces 232 of the lens surfaces 232 of the plurality of unit lenses 231, or all the lens surfaces 232. May be provided.
Here, since the reflection layer 22 shown in FIG. 4 has a regular reflectance Rt of 57.8% and a diffuse reflectance Rd of 43.9%, the incident image light is efficiently reflected to the viewer side. be able to. The reflective layer 22 has a regular reflectance Rt of 50% <Rt <70% and a diffuse reflectance Rd of 10% <Rd <50% in order to efficiently reflect incident video light. desirable.

The coating material forming the reflective layer 22 is composed of a scale-like metal thin film 22a, a binder, a drying aid, a control agent, and the like. This paint preferably has a viscosity in the range of 50 to 1000 [cp] (measurement temperature 23 degrees Celsius) from the viewpoint of easy application with a spray gun.
This metal thin film 22a is aluminum formed in a scale shape, and the thickness dimension thereof is formed in the range of 15 to 150 nm, more preferably in the range of 20 to 80 nm. In addition, the metal thin film 22a has an average value of dimensions in the vertical and horizontal directions orthogonal to the thickness direction (hereinafter referred to as vertical and horizontal dimensions) equal to the lens height h of the unit lens 231, that is, 0. It is preferably formed to 35 to 78 μm. Here, the equivalent to the lens height h is not only the case where the vertical and horizontal dimensions of the metal thin film are equal to the lens height h, but also the case where it approximates the lens height h (for example, with respect to the lens height h). -30% to + 30% size range).

Here, if the metal thin film 22a is disposed substantially parallel to the non-lens surface 233, when the external light is incident on the non-lens surface 233, the external light is reflected by the non-lens surface 233 and the observer side. May result in a decrease in the contrast of the video. Therefore, by making the vertical dimension and the horizontal dimension of the metal thin film 22a equal to the lens height h as described above, when the paint is applied to the back side of the lens layer 23, the metal thin film 22a becomes non-lens. It can suppress arrange | positioning substantially parallel with respect to the surface 233. FIG. Thereby, even if external light injects into the non-lens surface 233, the reflection layer 22 can be diffused in the edge part of a metal thin film, and can suppress as much as possible that it reflects in an observer side.
The metal thin film 22a is preferably contained within a range of 3 to 15% by weight with respect to the weight of the entire coating material from the viewpoint of ensuring the light reflecting function as the reflecting layer.

The binder is a transparent bonding agent composed of a thermosetting resin, and is a base material that forms the reflective layer 22. In the present embodiment, the binder uses a urethane-based thermosetting resin, but the binder is not limited to this, and an epoxy-based thermosetting resin may be used, or an ultraviolet curable resin or the like may be used. May be. The binder may be used as a two-component curable type by adding a curing agent. If it is a urethane resin, polyisocyanate or the like can be used, and if it is an epoxy resin, amines or the like can be used. Can be used.
The drying aid is a solvent that adjusts the drying time of the paint applied to the lens layer to a predetermined time, and is a so-called slow drying solvent. In the present embodiment, a predetermined amount of the drying aid is included in the coating so that the time until drying of the coating applied to the back side of the lens layer 23 is approximately one hour. As the drying aid, for example, a mixed solvent of propylene glycol monomethyl ether acetate, ethylene glycol monobutyl ether, diisobutyl ketone, and 3-methoxy-1-butyl acetate can be used.
The control agent is a solvent that controls the orientation of the metal thin film 22a contained in the paint. When the control agent is contained in the paint, the metal thin film 22 a can be disposed substantially parallel to the lens surface 232. As the control agent, for example, silica, alumina, aluminum hydroxide, acrylic oligomer, silicon or the like can be used.

As shown in FIG. 3B, the reflection layer 22 is a lens in the arrangement direction of the unit lenses 231 from the viewpoint of ensuring the light reflection characteristics and maintaining the appearance of the back side of the reflection screen 20. It is desirable that the thickness T (film thickness) in the direction perpendicular to the lens surface 232 at the central portion Q of the surface 232 is in the range of 8 μm ≦ T ≦ 15 μm.
If the thickness T of the reflective layer 22 is less than 8 μm, the reflectivity of the reflective layer 22 may be reduced, and the image light may not be sufficiently reflected. In the reflective layer 22 exposed to the side, there are portions where the coating film is present and portions where the coating film is not present, and there is a possibility that unevenness or blurring may occur in the appearance and the appearance on the back side of the reflective screen 20 may be impaired. .
Further, when the thickness T of the reflective layer 22 is larger than 15 μm, a part of the metal thin film 22a included in the reflective layer 22 is not arranged substantially parallel to the lens surface and is partially perpendicular to the lens surface. And the appearance of the back side of the reflective layer 22 is uneven, and the appearance of the back side of the reflective screen 20 may be impaired.

The surface layer 25 is a layer provided on the image source side (observer side) of the base material layer 24. The surface layer 25 of the present embodiment forms the outermost surface of the reflection screen 20 on the image source side.
The surface layer 25 of the present embodiment has a hard coat function and an antiglare function, and an ultraviolet curable resin (for example, urethane acrylate) having a hard coat function is provided on the surface of the base layer 24 on the image source side. The ionizing radiation curable resin is applied so that the film thickness of the coating film is about 10 to 100 μm, and the fine uneven shape (mat shape) is cured by transferring it to the surface of the resin film. Is shaped and formed.

The surface layer 25 is not limited to the above example, and one or more necessary functions such as an antireflection function, an antiglare function, a hard coat function, an ultraviolet absorption function, an antifouling function, and an antistatic function are appropriately selected. Can be provided. Further, a touch panel layer or the like may be provided as the surface layer 25.
Further, as the surface layer 25, a layer having an antireflection function, an ultraviolet absorption function, an antifouling function, an antistatic function, or the like may be provided as a separate layer between the surface layer 25 and the base material layer 24.
Further, the surface layer 25 is a layer separate from the base material layer 24 and may be bonded to the base material layer 24 by an adhesive material (not shown) or the like, and is opposite to the lens layer 23 of the base material layer 24. It may be formed directly on the side (video source side) surface.

Returning to FIG. 2, the state of the image light and the external light incident on the reflection screen 20 of this embodiment will be described. In FIG. 2, the refractive index of the surface layer 25, the colored layer 242, the light diffusing layer 241, and the lens layer 23 is assumed to be equal to facilitate understanding, and the light of the light diffusing layer 241 with respect to the image light L1 and the external light G. The diffusion action and the like are omitted.
As shown in FIG. 2, most of the image light L <b> 1 projected from the image source LS enters from below the reflection screen 20, passes through the surface layer 25 and the base material layer 24, and is a unit lens 231 of the lens layer 23. Incident to

Then, the image light L1 enters the lens surface 232, is reflected by the reflective layer 22, travels toward the observer O, and exits from the reflective screen 20 in a substantially front direction. Therefore, since the image light L1 is efficiently reflected and reaches the observer O, a bright image can be displayed. At this time, the image light is reflected by the reflective layer 22, passes through the colored layer 242, and then enters the light diffusing layer 241. Therefore, even if the position of the diffusing agent contained in the light diffusing layer 241 has become obvious. Therefore, the front luminance can be made uniform without decreasing, and the occurrence of glare in the video can be suppressed.
Since the image light L1 is projected from below the reflection screen 20, and the angle β (see FIG. 3B) is larger than the incident angle of the image light L1 at each point in the screen vertical direction of the reflection screen 20, The image light L1 does not directly enter the non-lens surface 233, and the non-lens surface 233 does not affect the reflection of the image light L1.

On the other hand, unnecessary external light G (G 1, G 2) such as illumination light is incident mainly from above the reflection screen 20 and passes through the surface layer 25 and the base material layer 24 as shown in FIG. Is incident on the unit lens 231.
A part of the external light G1 enters the non-lens surface 233, but is diffused at the end of the metal thin film 22a of the reflective layer 22 formed on the back side of the non-lens surface 233 and reaches the observer O side. Even so, the amount of light is much smaller than that of the image light L1. Further, a part of the external light G2 is reflected by the lens surface 232 and mainly travels to the lower side of the reflection screen 20, so that it does not reach the observer O side directly. Significantly less than the image light L1. Further, a part of the external light enters the reflective screen 20 and is absorbed by the colored layer 242. Therefore, the reflective screen 20 can suppress a decrease in the contrast of the image due to the external light G1, G2, and the like.
From the above, according to the reflective screen 20 of the present embodiment, a bright and good image can be displayed even in a bright room environment.

Here, an example of the manufacturing method of the reflective screen 20 of this embodiment is demonstrated.
FIG. 5 is a diagram for explaining an example of the manufacturing method of the reflective screen 20 of the present embodiment.
As shown in FIG. 5A, the light diffusing layer 241 and the colored layer 242 are integrally formed by coextruding a resin containing a diffusing agent and a resin containing a coloring material at a predetermined thickness, respectively. The base material layer 24 is formed by molding. Here, it is assumed that the base material layer 24 has a web shape.

Next, as shown in FIG. 5B, an ultraviolet curable resin such as urethane acrylate is applied on the surface of the base material layer 24 on the image source side (surface on the light diffusion layer 241 side). The uneven shape (mat shape) is cured by transferring it to the surface of the resin film, and the surface layer 25 having a fine uneven shape is formed on the surface. In the present embodiment, the surface layer 25 has a surface roughness in the range of 0.1 to 3 μm and a haze value in the range of 5 to 20%.
Note that a masking material (not shown) may be detachably bonded onto the surface layer 25 and may be flowed to the next step. As the masking material, for example, a transparent or substantially transparent sheet-like member can be used, and has a function of preventing the surface layer 25 from being stained or damaged in the subsequent manufacturing process.

Next, the surface layer 25 and the base material layer 24 are cut into a predetermined size to form a single wafer.
Then, as shown in FIG. 5C, the lens layer 23 is formed on the surface (surface on the colored layer 242 side) on the back surface side of the base material layer 24 by an ultraviolet molding method or the like.
The lens layer 23 has a circular Fresnel lens shape filled with an acrylic ultraviolet curable resin on the surface opposite to the surface on which the surface layer 25 of the base material layer 24 is laminated (the surface on the colored layer 242 side). It is formed by, for example, releasing the mold from the mold after pressing the mold to be shaped, irradiating and curing with ultraviolet rays. The method for forming the lens layer 23 may be selected as appropriate, and is not limited to this.

Next, as shown in FIG. 5D, the reflective layer 22 is formed by spraying a coating material (resin) containing the scaly metal thin film 22a on the back side of the lens layer 23 with a spray gun (not shown). . Application of the paint is performed by moving the spray gun from the lower end portion in the vertical direction of the screen to the upper end side at a predetermined moving pitch (for example, 70 mm pitch) while moving the lens layer 23 in the horizontal direction of the screen. At this time, the direction of the spray gun is preferably substantially perpendicular to the lens surface 232 in order to facilitate the arrangement of the metal thin film 22 a substantially parallel to the lens surface 232.
Next, the reflective screen 20 is completed by peeling the masking material or the like from the surface layer 25 or performing a subsequent process such as a further cutting process.
In the above description, the reflective layer forming step is an example in which the reflective layer 22 is formed by applying a paint containing the scaly metal thin film 22a with a spray gun. Not a thing. For example, the reflective layer 22 may be formed by a so-called roll coater method in which a rotating roll coated with a paint is pressed against a substrate (lens layer) and applied.

Here, conventionally, the reflective layer provided on the lens layer of the reflective screen that has been mainly manufactured (hereinafter referred to as a reflective screen of another example) has been formed by a vacuum deposition method in which a metal such as aluminum is deposited. The reflective layer formed by this vapor deposition can reflect image light efficiently, but the thickness is very thin (for example, about 800 mm), so that the back side of the reflective screen can be prevented from being seen through or reflected. In order to suppress the oxidation of the layer, it was necessary to provide a protective layer on the back side of the reflective layer.
For this reason, in the reflective screen of another example, it is necessary to provide a vapor deposition processing step and a protective layer forming step in forming the reflective layer.

On the other hand, the reflective screen 20 of the present embodiment is manufactured by a vacuum deposition method because the plurality of scale-like metal thin films 22a contained in the coating material are arranged substantially parallel to the lens surface 232. The reflective screen 20 can be manufactured efficiently and simply as compared with the reflective screens of other examples. That is, the reflective layer of the reflective screen of the other example described above is often used for forming the lens layer because the deposited metal is deposited after the lens layer is placed in a vacuum environment using a vacuum deposition apparatus or the like. However, since the reflective layer 22 of the reflective screen 20 of the present embodiment is coated with a paint containing the metal thin film 22a, the time required for forming the lens layer is shortened. In addition, the necessary work can be simplified.
Moreover, since the reflective screen 22 of the present embodiment is formed so that the reflective layer 22 covers the back side of the unit lens 231, it is not necessary to provide a protective layer like the reflective screen of other examples. In this respect as well, it can be easily manufactured as compared with the reflective screens of other examples. Moreover, the manufacturing cost of the reflective screen 20 can also be reduced.

  Furthermore, since the reflective screen of another example has a reflective layer formed by vapor deposition, the reflective screen as a whole has a yellowish color, but the reflective screen 20 of this embodiment has a plurality of reflective layers 22. Since it is formed of a scale-like metal thin film, it has a bluish color as a whole. Here, when adjusting the color of the image light projected from the image source to adjust the color of the image displayed on the reflective screen, when the reflective screen is more bluish than when it is yellowish The correction to white becomes easier. Therefore, the reflective screen 20 of the present embodiment can easily perform color correction by adjusting the video source, as compared with the reflective screens of other examples.

(Evaluation of image glare and peak gain)
Next, the reflective screens of a plurality of examples and comparative examples are manufactured, and glare and peak gain of an image on each reflective screen are evaluated.
The reflective screen of each example and each comparative example is formed in a size of 100 inches diagonal.
The reflective screen of each example and the reflective screen of Comparative Example 4 have the same layer configuration as the reflective screen 20 of the above-described embodiment, that is, in order from the image source side, the surface layer 25, the light diffusion layer 241, the colored layer 242, and the lens. The layer 23 and the reflective layer 22 are laminated.
The reflective screens of Comparative Example 1, Comparative Example 2, and Comparative Example 3 are in a form in which the positions of the colored layer and the light diffusing layer are switched as compared with the reflective screens of the examples, that is, in order from the image source side. A layer, a colored layer, a light diffusion layer, a lens layer, and a reflective layer are laminated.

In the light diffusing layers of the reflective screens of Examples 1 to 3, Example 5, Comparative Example 2 and Comparative Example 4, the mixing ratio of the diffusing agent (the mixing ratio (weight ratio) with respect to the total weight of the light diffusing layer) is 7%. Yes, the thickness D in the thickness direction is 150 μm.
In the light diffusion layers of the reflective screens of Example 4 and Comparative Example 3, the mixing ratio of the diffusing agent (the mixing ratio (weight ratio) with respect to the total weight of the light diffusion layer) is 11.6%, and the thickness D in the thickness direction is 250 μm.
The light diffusion layer of the reflective screen of Comparative Example 1 has a diffusing agent content of 23% and a thickness D in the thickness direction of 150 μm.

The reflective screen of Example 1 has a thickness T in the thickness direction of the colored layer of 430 μm, a shortest distance p of 450 μm, and a weight of 2.65 kg.
In the reflective screen of Example 2, the thickness T in the thickness direction of the colored layer is 1050 μm, the shortest distance p is 1070 μm, and its weight is 4.08 kg.
In the reflective screen of Example 3, the thickness T in the thickness direction of the colored layer is 1350 μm, the shortest distance p is 1370 μm, and its weight is 5.10 kg.
In the reflective screen of Example 4, the thickness T in the thickness direction of the colored layer is 1350 μm, the shortest distance p is 1370 μm, and its weight is 5.44 kg.
In the reflective screen of Example 5, the thickness T in the thickness direction of the colored layer is 1650 μm, the shortest distance p is 1670 μm, and its weight is 6.19 kg.

The reflective screen of Comparative Example 1 has a thickness T in the thickness direction of the colored layer of 1350 μm, a shortest distance p of 20 μm, and a weight of 5.10 kg.
The reflective screen of Comparative Example 2 has a thickness T in the thickness direction of the colored layer of 1350 μm, a shortest distance p of 20 μm, and a weight of 5.10 kg.
The reflective screen of Comparative Example 3 has a thickness T in the thickness direction of the colored layer of 1250 μm, a shortest distance p of 20 μm, and a weight of 5.10 kg.
The reflective screen of Comparative Example 4 has a thickness T in the thickness direction of the colored layer of 300 μm, a shortest distance p of 320 μm, and a weight of 1.53 kg.

FIG. 6 is a table summarizing evaluation results of glare and peak gain of the images of the reflective screens of the example and each comparative example.
The evaluation of the image glare in FIG. 6 is evaluated by the visual sense of the measurer, and the image glare is suppressed to the extent that it can be used to the same extent as a reflective screen that has been mainly used conventionally. The case where there was “G” was marked, and the case where the glare of the image was noticeable was marked “X”.
In the comprehensive evaluation in FIG. 6, the evaluation of the glare of the image is “◯”, the peak gain PG satisfies the above-mentioned preferable range (PG ≧ 0.8), and the weight of the reflective screen is Comparative Example 1. The case where it was equal to or less than that of the reflective screen (5.10 kg or less) was designated as “◎”.
In addition, when the evaluation of the image glare is “x”, the peak gain PG does not satisfy the above-mentioned preferable range, or the weight of the reflective screen is larger than 5.1 kg, “◯” is given.

  Here, “black luminance” in FIG. 6 refers to the luminance of the screen surface in a state where no image is displayed on the reflective screen in a bright room environment. This black luminance is measured in a bright room environment by installing a luminance meter (manufactured by Konica Minolta, LS-110) at a distance of 3.2 m from the geometric center of the screen surface to the viewer side in the normal direction of the screen surface. The average value of the measurement results of the geometric center A (see FIG. 1) of the screen surface.

  The peak gain PG is a light (white light) projected from the image source to the reflective screen, and the illuminance at the incident surface where the light is incident on the reflective screen and the light reflected from the reflective layer and emitted from the reflective screen. The maximum value of the gain (= k · luminance / illuminance, k is a proportional coefficient) obtained from the luminance of Here, the illuminance is measured by placing an illuminometer (manufactured by Konica Minolta, T-10A) on the geometric center A of the screen surface of the reflective screen. (LS manufactured by Konica Minolta, LS-110) was measured by placing it at a position 3.2 m away from the geometric center A of the reflective screen on the viewer side in the normal direction of the screen surface. The image source is arranged at a position 650 mm downward from the geometric center A on the viewer side of the reflection screen and 400 mm away from the sheet surface to the viewer side in the normal direction.

FIG. 7 is a diagram for explaining the half-value angle in the luminance distribution. The vertical axis of the luminance distribution shown in FIG. 7 is the gain, and the horizontal axis is the observation angle in the horizontal direction or the vertical direction.
As shown in FIG. 7, the viewing angle means that the gain value is half of the maximum value in any one of the left and right directions of the screen from the position of the screen surface of the reflection screen where the gain value is the maximum value. The so-called half-value angle is the observation angle at which

As shown in FIG. 6, the reflective screen of Comparative Example 1 has a weight of 5.10 kg and a scintillation value S of S = 6.9%, but the shortest distance between the reflective layer and the light diffusion layer. Since the distance was 20 μm and the light diffusion layer was close to the reflective layer, the evaluation of the glare of the image was “good”. The reflective screen of Comparative Example 1 had a peak gain PG of PG = 0.61 and did not satisfy the above-described preferable range (PG ≧ 0.8), so the overall evaluation was “good”.
The reflective screen of Comparative Example 2 has a weight of 5.10 kg and satisfies 5.10 kg or less, and the peak gain PG is PG = 0.99 and satisfies the above-described preferable range (PG ≧ 0.8). The scintillation value S was S = 8.5%, and the evaluation of the glare of the video was x, so the overall evaluation was “good”.
The reflective screen of Comparative Example 3 has a weight of 5.10 kg and satisfies 5.10 kg or less, and the peak gain PG is PG = 0.90, which satisfies the above preferable range (PG ≧ 0.8). The scintillation value S was S = 8.1%, and the evaluation of the glare of the video was x, so the overall evaluation was “good”.
The reflective screen of Comparative Example 4 has a weight of 1.5 kg and satisfies 5.10 kg or less, and the peak gain PG is PG = 1.00, which satisfies the above preferable range (PG ≧ 0.8). The scintillation value S was S = 7.6%, and the evaluation of the glare of the video was x, so the overall evaluation was “good”.

On the other hand, in the reflective screen of Example 1, the scintillation value S is S = 6.9%, the evaluation of image glare is ◯, and the peak gain PG is PG = 0.98. The above-mentioned preferable range (PG ≧ 0.8) was satisfied, the weight was 2.65 kg, and 5.10 kg or less was satisfied, so the overall evaluation was “◎”.
In the reflection screen of Example 2, the scintillation value S is S = 5.1%, the evaluation of the image glare is ◯, and the peak gain PG is PG = 1.02. PG ≧ 0.8) and the weight was 4.08 kg, satisfying 5.10 kg or less, so the overall evaluation was “◎”.
In the reflective screen of Example 3, the scintillation value S is S = 4.0%, the evaluation of the image glare is ◯, and the peak gain PG is PG = 1.01. PG ≧ 0.8) and the weight was 5.10 kg, satisfying 5.10 kg or less, and the overall evaluation was “◎”.
In the reflective screen of Example 4, the scintillation value S is S = 3.9%, the evaluation of image glare is ◯, and the peak gain PG is PG = 0.88. PG ≧ 0.8), but the weight was 5.44 kg, which was heavier than 5.10 kg, so the overall evaluation was “good”.
In the reflective screen of Example 5, the scintillation value S is S = 3.0%, the evaluation of image glare is ◯, and the peak gain PG is PG = 1.02. PG ≧ 0.8), but the weight was 6.19 kg, which was heavier than 5.10 kg, so the overall evaluation was “good”.

From the above evaluation results, when the mixture ratio of the diffusing agent is increased and the glare of the image is suppressed as in the reflective screen of Comparative Example 1, the peak gain PG is decreased and the preferable range (PG ≧ 0.8). It was confirmed that it would be out of the range. On the other hand, if the blending ratio H of the diffusing agent is reduced to keep the peak gain PG within a preferable range, the image glare is noticeably generated as in the reflective screens of Comparative Example 2 and Comparative Example 3. It was confirmed that.
Further, even if the light diffusing layer is arranged on the image source side of the lens layer and the coloring layer as in the reflective screen of Comparative Example 4, the value of the shortest distance p can be obtained. It was confirmed that when the image was 450 μm or less, the glare of the video was noticeably generated.

On the other hand, in the reflective screens of the respective examples, the light diffusion layer is arranged on the image source side with respect to the lens layer and the coloring layer, the shortest distance p is 450 μm or more, and the scintillation value S is 7% or less. It was confirmed that, when the peak gain PG is set to 0.8 or more, it is possible to suppress glare of the image and improve the front luminance even when the position of the diffusing agent is easily manifested.
Moreover, when the shortest distance p is larger than 1370 μm as in the reflective screen of Example 5, the thickness of the colored layer becomes too thick and the weight of the screen becomes too heavy. It has been confirmed that the screen is heavier than a conventionally used screen such as the reflective screen of Example 2.

Furthermore, it was confirmed that the glare of the image is suppressed when the scintillation value S is S ≦ 7.0 and the shortest distance p is 450 μm or more as in the reflective screens of the respective embodiments. As a result, it was confirmed that the evaluation of the glare of the video was ○.
Further, the reflective screen of Example 3 is different from the reflective screen of Comparative Example 2 only in that the colored layer is located on the back side of the light diffusion layer, but the black luminance of both screens is different. Since the values were close to each other and the viewing angle values were also close to each other, it was confirmed that there was almost no effect on the black luminance and the viewing angle due to the difference in the positions of the light diffusion layer and the colored layer.

As described above, the reflective screen of the present embodiment has the following effects.
(1) In the reflective screen 20, the shortest distance p between the reflective layer 22 and the light diffusion layer 241 in the thickness direction is p ≧ 450 μm, the scintillation value S satisfies S ≦ 7%, and the peak gain PG is PG ≧ 0.8 is satisfied. Thereby, the reflective screen 20 can improve the front luminance while suppressing the glare of the image.
(2) Since the shortest distance p of the reflective screen 20 is p ≦ 1370 μm, the overall weight of the reflective screen due to an excessively large distance between the reflective layer 22 and the light diffusion layer 241 is suppressed. can do. Moreover, it can also suppress that the image | video displayed on the reflective screen 20 blurs because the distance between the reflective layer 22 and the light-diffusion layer 241 becomes large too much.
(3) Since the reflective screen 20 is provided with the colored layer 242 between the light diffusing layer 241 and the reflective layer 22, the light transmittance of the reflective screen 20 is adjusted, and the light diffusing layer and the reflective layer are The shortest distance p can be set to a desired distance.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications and changes can be made as in the modifications described later, and these are also included in the present invention. Within the technical scope. In addition, the effects described in the embodiments are merely a list of the most preferable effects resulting from the present invention, and the effects of the present invention are not limited to those described in the embodiments. It should be noted that the above-described embodiment and modifications described later can be used in appropriate combination, but detailed description thereof is omitted.

(Deformation)
FIG. 8 is a diagram illustrating details of the lens layer and the reflective layer of the reflective screen according to the modification, and corresponds to FIG.

(1) In the above-described embodiment, an example in which the reflective screen 20 is formed so that the reflective layer 22 covers the lens surface 232 and the non-lens surface 233 of the unit lens 231 has been described. Not a thing. For example, as shown in FIG. 8, the reflection layer 22 is a part of the lens surface 232 and contributes only to the non-lens surface 233 side of the adjacent unit lens 231, that is, to the reflection of the image light on the lens surface 232. You may make it provide only in the part to perform. In this case, since the reflective layer 22 is not formed on part of the lens surface 232 and the non-lens surface 233, it is necessary to provide a concealing layer (protective layer) that conceals the back side of the reflective layer 22.
(2) Although the metal thin film 22a of the reflective layer 22 of the above-mentioned embodiment demonstrated the example which uses scale-like aluminum, it is not limited to this, For example, metals, such as silver and nickel, are used. It is also possible to do.
(3) In order to maintain the flatness of the screen, the reflective screen 20 of the above-described embodiment may be configured to include a transparent substrate layer having high rigidity made of glass or resin.

(4) In the above-described embodiment, the lens surface 232 and the non-lens surface 233 are planar as shown in FIG. 2 and the like, but the present invention is not limited to this. A part of the lens surface 233 may be curved.
In the present embodiment, the lens surface 232 and the non-lens surface 233 of the unit lens 231 are both examples. However, the present invention is not limited to this. For example, at least one surface includes a plurality of surfaces. It is good also as a form comprised from.
Furthermore, in the present embodiment, the unit lens 231 has an example in which the cross-sectional shape illustrated in FIG. 2 or the like is a substantially triangular shape. However, the present invention is not limited thereto, and for example, the cross-sectional shape is a substantially trapezoidal shape. The non-lens surface may be opposed to the screen surface across a top surface parallel to the screen surface. At this time, the top surface is preferably formed in a region that does not contribute to the reflection of the image light. A reflective layer may be formed on the top surface, or the top surface may be covered with a protective layer.

(5) The light diffusing layer 241 and the colored layer 242 may be formed as a base material layer 24 by bonding the light diffusing layer 241 and the colored layer 242 separately formed with an adhesive or the like.

(6) In the above-described embodiment, the video source LS is positioned below the reflective screen 20 (the reflective screen unit 10) in the vertical direction, and the video light L is projected obliquely from below the reflective screen 20. However, the present invention is not limited to this. For example, the video source LS may be positioned above the reflective screen 20 in the vertical direction, and the video light L may be projected obliquely from above the reflective screen 20.

DESCRIPTION OF SYMBOLS 1 Image display system 20 Reflective screen 22 Reflective layer 22a Metal thin film 23 Lens layer 231 Unit lens 232 Lens surface 233 Non-lens surface 24 Base material layer 241 Light diffusion layer 242 Colored layer 25 Surface layer LS Image source

Claims (4)

A reflective screen that reflects video light projected from a video source and displays it on a screen,
A lens layer having a lens surface and a non-lens surface, and a plurality of unit lenses that are convex on the back side;
A reflective layer that reflects light and is formed of a resin containing a plurality of scale-like metal thin films on at least a part of the lens surface;
A light diffusion layer provided on the image source side of the reflective layer and diffusing light;
The shortest distance p between the reflective layer and the light diffusion layer in the thickness direction of the reflective screen is p ≧ 450 μm,
The scintillation value S satisfies S ≦ 7% and the peak gain PG satisfies PG ≧ 0.8;
Reflective screen featuring. The reflective screen according to claim 1.
The shortest distance p is p ≦ 1370 μm;
Reflective screen featuring. The reflective screen according to claim 1 or 2,
A colored layer for adjusting light transmittance is formed between the light diffusion layer and the reflective layer,
Reflective screen featuring. The reflective screen according to any one of claims 1 to 3,
An image source for projecting image light onto the reflective screen;
A video display system comprising: