JP5040709B2 - Reflective screen and manufacturing method thereof - Google Patents

Description

  The present invention relates to a reflective screen and a method for manufacturing the same.

2. Description of the Related Art Conventionally, a reflection screen that makes it possible to observe a projection image by reflecting the image is known. As such a reflective screen, a plurality of convex unit shape portions having the same shape are regularly arranged two-dimensionally on the front side of the screen substrate, and a part of the convex unit shape portions toward the projection light incident direction. A reflective screen is disclosed in which a reflective surface is formed only on the surface portion (see, for example, Patent Document 1).
JP 2006-215162 A

However, the following problems exist in the conventional technology as described above.
For example, when the projector is arranged on the lower front side of the screen and the projected image is irradiated obliquely upward from the projector toward the screen, the surface of the screen is formed into a convex spherical surface. Only the area located in the vicinity of the straight line connecting the projector and the spherical surface contributes to the reflection of the projection light to the front observation side, and the other areas have a higher proportion of reflection in the other direction. There is a problem in that the contrast of the projected image is lowered due to insufficient reflection on the front observer side.

  The present invention has been made in consideration of the above points, and a reflective screen capable of efficiently reflecting light from an oblique direction to the observation side in front of the reflective screen and improving the contrast of the projected image. It aims at providing the manufacturing method.

In order to achieve the above object, the present invention employs the following configuration.
The reflective screen of the present invention has a plurality of reflective portions on the observation surface of the screen substrate, and is directed from the projection portion arranged at a position shifted in a direction perpendicular to the normal line of the observation surface toward the observation surface. A reflection screen that reflects obliquely emitted projection light to an observation side, wherein the reflection portion has a concave or convex spherical surface, and at least a part of the spherical surface irregularly reflects the projection light. It has a rough surface processing section that has been subjected to a rough surface treatment so as to have a predetermined roughness.
Therefore, in the reflective screen of the present invention, the rough surface processing unit irregularly reflects the projection light even in a region of the reflection unit that does not contribute to reflecting the projection light to the front observation side unless the rough surface processing is performed. As a result, the projection light can be reflected to the observation side, and the contrast of the projection image can be improved.

In the reflective screen having the above-described configuration, it is possible to suitably employ a configuration in which the rough surface treatment portion is provided at the peripheral edge portion of the spherical surface.
As a result, in the present invention, the rough surface processing unit irregularly reflects the projection light even if it is a peripheral portion of a spherical surface that is difficult to contribute when reflecting the projection light to the front observation side unless the rough surface is processed. The projection light can be reflected to the observation side.

Moreover, in the reflective screen of the said structure, the said rough surface process part can employ | adopt suitably the structure provided in at least one part of the said reflection part arrange | positioned in the peripheral part of the said screen board | substrate.
As a result, in the present invention, the rough surface processing unit irregularly reflects the projection light even if it is a peripheral part of the screen substrate that is difficult to contribute when reflecting the projection light to the front observation side unless the rough surface processing is performed. The projection light can be reflected to the observation side. In particular, the amount of projection light that reaches the periphery of the screen substrate tends to decrease, but the amount of projection light reflected to the observation side in the periphery can be increased, thus reducing projection unevenness within the screen substrate. can do.

Further, in the case where the rough surface processing unit is configured to be provided in at least a part of the reflection unit disposed in the peripheral portion of the screen substrate, the reflection unit having the rough surface processing unit includes the rough surface processing unit. A configuration having a spherical surface formed with a diameter larger than that of the reflecting portion that does not have the shape can be suitably employed.
Thereby, in this invention, it becomes possible to increase the light quantity of the projection light which approaches a plane by the diameter of a spherical surface becoming large, and reflects on an observation side.

In the present invention, it is possible to suitably employ a configuration in which the rough surface treatment portion is formed in an average roughness range of 10 nm to 50 μm.
When the average roughness is less than 10 nm, sufficient irregular reflection cannot be obtained. When the average roughness exceeds 50 μm, the irregular reflection of the projection light is not stable, and the visibility of the image may be lowered. However, these problems can be avoided in the present invention.

Moreover, in the case of the structure which has the said average roughness, it is preferable that it is 1/10 or less of the radius of the said spherical surface as an average roughness of the said rough surface process part.
If the average roughness exceeds 1/10 of the radius of the spherical surface, the shape of the spherical surface of the reflecting portion may not be maintained. However, in the present invention, the diffusely reflecting surface (rough surface) is maintained with the spherical surface maintained in shape. Surface treatment section) can be formed.

Moreover, as a radius of the said spherical surface of the said reflection part, the structure formed in the range of 30 micrometers-500 micrometers can be employ | adopted suitably.
If the radius of the spherical surface is less than 30 μm, moire fringes (interference fringes) are likely to occur on the screen, and if it exceeds 500 μm, the visibility of the image projected on the screen may be reduced. It can be avoided.

Moreover, in this invention, the structure by which the said reflection part is arrange | positioned by the distribution which becomes sparse as the distance from the said projection part becomes large can be employ | adopted suitably.
Thereby, in this invention, since the number of the reflection parts in the position where the distance from a projection part is large reduces, the location which reflects projection light to an observation side also decreases. For this reason, in the present invention, the reflected light from the reflecting unit at a position where the distance from the projection unit is large to the observation side is reduced, and the reflected light from the reflecting unit at a position where the distance from the projection unit is small can be made equivalent. The projection light can be uniformly reflected to the observation side in front of the reflection screen.

As the arrangement distribution of the reflection portions, a configuration adjusted according to the reflection distribution of the projection light from the observation surface can be suitably employed.
As a result, in the present invention, for example, at an edge portion (peripheral portion) of the reflection screen, where the reflection of the projection light is small, the arrangement of the reflection portions is made dense to increase the number of reflection portions and the amount of reflection is increased. Can be adjusted as follows.

As the reflection part, a structure having a reflection film on a surface facing the projection part and a light absorption surface in a non-formation region of the reflection film can be suitably employed.
Accordingly, in the present invention, the projection light projected from the projection unit is reflected by the reflection film to the observation side of the screen substrate, and outside light is absorbed by the non-formation area of the reflection film, thereby improving the contrast of the projection image. Can do. In addition, when the reflecting portion has a concave spherical surface, the reflecting film is formed in a concave shape, so that the projection light irradiated on the outer edge of the reflecting screen is reflected in a direction closer to the normal direction of the reflecting screen. The contrast of the projected image can be improved.

The reflective screen of the present invention is characterized in that a protective layer is provided on the observation surface side of the screen substrate.
By comprising in this way, damage and deterioration of a reflecting film can be prevented.

In the present invention, the screen substrate may be formed of a light-transmitting material, and the concave spherical surface may be formed in a recess provided on a surface opposite to the observation surface of the screen substrate. It can be suitably employed.
With this configuration, the reflective film is formed in a convex shape when viewed from the observation side. The projection light is transmitted through the screen substrate, reflected by the convex reflection film, and reflected to the observation side. Further, the screen substrate itself can function as a protective layer for the reflective film with respect to the viewing surface side of the reflective screen.

In the present invention, the screen substrate is formed of a light-transmitting material, and the convex spherical surface is formed on a convex portion provided on a surface opposite to the observation surface of the screen substrate. Can also be suitably employed.
With this configuration, the reflective film is formed in a concave shape when viewed from the observation side. The projection light is transmitted through the screen substrate, reflected by the concave reflective film, and reflected to the observation side. Thereby, the projection light applied to the outer edge of the reflection screen can be reflected in a direction closer to the normal direction, and the contrast of the projection image on the reflection screen can be improved.
In addition, a light-transmissive screen substrate can function as a protective layer for the reflective film.

Moreover, the reflection screen of the present invention is characterized in that an antireflection layer is provided on the observation surface side of the screen substrate.
With such a configuration, it is possible to prevent the projection light and the external light from being reflected by other than the reflection film, and to improve the contrast of the projection image.

Moreover, the reflective screen of the present invention is characterized in that the screen substrate is formed of a flexible material.
By comprising in this way, the reflective screen which has flexibility can be formed, and winding up accommodation of a reflective screen is attained.

On the other hand, the manufacturing method of the reflection screen of the present invention includes a plurality of reflection portions on the observation surface of the screen substrate, and the projection portion arranged at a position shifted in a direction perpendicular to the normal line of the observation surface, A method of manufacturing a reflective screen for reflecting projection light emitted obliquely toward an observation surface to an observation side, wherein the reflection portion has a concave or convex spherical surface, and at least a part of the spherical surface Is provided with a rough surface treatment step for roughening the surface so as to have a predetermined roughness for irregularly reflecting the projection light.
Thereby, in this invention, even if it is an area | region which does not contribute when reflecting a projection light to the front observation side unless a rough surface process is carried out among reflection parts, a rough surface process part reflects a projection light irregularly. The projected light can be reflected to the observation side, and the contrast of the projected image can be improved.

In the manufacturing method of the said reflective screen, it can employ | adopt suitably also providing the said rough surface process part in the peripheral part in the said spherical surface.
As a result, in the present invention, the rough surface processing unit irregularly reflects the projection light even if it is a peripheral portion of a spherical surface that is difficult to contribute when reflecting the projection light to the front observation side unless the rough surface is processed. The projection light can be reflected to the observation side.

Moreover, in the said manufacturing method of a reflective screen, it can employ | adopt suitably also providing the said rough surface process part in at least one part of the said reflection part arrange | positioned in the peripheral part of the said screen board | substrate.
As a result, in the present invention, the rough surface processing unit irregularly reflects the projection light even if it is a peripheral part of the screen substrate that is difficult to contribute when reflecting the projection light to the front observation side unless the rough surface processing is performed. The projection light can be reflected to the observation side. In particular, the amount of projection light that reaches the periphery of the screen substrate tends to decrease, but the amount of projection light reflected to the observation side in the periphery can be increased, thus reducing projection unevenness within the screen substrate. can do.

Further, in the case where the rough surface processing unit is configured to be provided in at least a part of the reflection unit disposed in the peripheral portion of the screen substrate, the reflection unit having the rough surface processing unit is changed to the rough surface processing unit. Forming with a spherical surface having a diameter larger than that of the reflection part not having a diameter can also be suitably employed.
Thereby, in this invention, it becomes possible to increase the light quantity of the projection light which approaches a plane by the diameter of a spherical surface becoming large, and reflects on an observation side.

Moreover, in this invention, the structure which forms the said rough surface process part in the range whose average roughness is 10 nm-50 micrometers can be employ | adopted suitably.
When the average roughness is less than 10 nm, sufficient irregular reflection cannot be obtained. When the average roughness exceeds 50 μm, the irregular reflection of the projection light is not stable, and the visibility of the image may be lowered. However, these problems can be avoided in the present invention.

Moreover, in the case of the structure which has the said average roughness, it is preferable that it is 1/10 or less of the radius of the said spherical surface as an average roughness of the said rough surface process part.
If the average roughness exceeds 1/10 of the radius of the spherical surface, the shape of the spherical surface of the reflecting portion may not be maintained. However, in the present invention, the diffusely reflecting surface (rough surface) is maintained with the spherical surface maintained in shape. Surface treatment section) can be formed.

Moreover, as a radius of the said spherical surface of the said reflection part, the structure formed in the range of 30 micrometers-500 micrometers can be employ | adopted suitably.
If the radius of the spherical surface is less than 30 μm, moire fringes (interference fringes) are likely to occur on the screen, and if it exceeds 500 μm, the visibility of the image projected on the screen may be reduced. It can be avoided.

As the rough surface treatment step, a procedure having a rough surface treatment step on the transfer surface onto which the reflective portion of the mold substrate is transferred can be suitably employed.
Thereby, in this invention, the screen board | substrate which has a rough surface process part can be manufactured easily, for example by pressing a thermoplastic resin to a transfer surface.
In this case, as the rough surface treatment, a procedure for roughening at least a part of the transfer surface by a shot blast method, a procedure for roughening at least a part of the transfer surface by a chemical frost method, or the mold substrate A procedure for roughening at least a part of the transfer surface can be adopted by using crystallized glass as a substrate and etching the crystallized glass.

In the present invention, it is also possible to suitably employ a procedure in which the reflecting portions are arranged with a sparse distribution as the distance from the projection portion increases.
Thereby, in this invention, since the number of the reflection parts in the position where the distance from a projection part is large reduces, the location which reflects projection light to an observation side also decreases. For this reason, in the present invention, the reflected light from the reflecting unit at a position where the distance from the projection unit is large to the observation side is reduced, and the reflected light from the reflecting unit at a position where the distance from the projection unit is small can be made equivalent. The projection light can be uniformly reflected to the observation side in front of the reflection screen.

In the reflection screen manufacturing method of the present invention, it is also preferable to adjust the distribution of the reflecting portions according to the reflection distribution of the projection light from the observation surface.
As a result, in the present invention, for example, at an edge portion (peripheral portion) of the reflection screen, where the reflection of the projection light is small, the arrangement of the reflection portions is made dense to increase the number of reflection portions and the amount of reflection is increased. Can be adjusted as follows.

In the reflective screen manufacturing method of the present invention, at least a step of forming a light absorbing surface on the observation surface side of the screen substrate and a step of forming a reflective film on the surface of the reflective portion facing the projection portion. The procedure which has can also be employ | adopted suitably.
Accordingly, in the present invention, the projection light projected from the projection unit is reflected by the reflection film to the observation side of the screen substrate, and outside light is absorbed by the non-formation area of the reflection film, thereby improving the contrast of the projection image. Can do. In addition, when the reflecting portion has a concave spherical surface, the reflecting film is formed in a concave shape, so that the projection light irradiated on the outer edge of the reflecting screen is reflected in a direction closer to the normal direction of the reflecting screen. The contrast of the projected image can be improved.

In the said procedure, it is preferable to arrange | position the vapor deposition source which has a target in the said projection part, and to vapor-deposit the said target on the surface which faces the said projection part of the said reflection part.
Thereby, in this invention, a reflective surface can be easily formed by vapor-depositing a target in the location where projection light is projected in a reflection part.

Moreover, in this invention, the procedure which has the process of providing a protective layer in the said observation surface side of the said screen board | substrate can also be employ | adopted suitably.
Thereby, in this invention, damage and deterioration of a reflecting film can be prevented.

  Hereinafter, embodiments of a reflective screen and a method for manufacturing the same according to the present invention will be described with reference to FIGS. In the following drawings, the scale is appropriately changed for each layer and each member so that each layer and each member can be recognized on the drawing. In the following description, an XYZ orthogonal coordinate system is set, and the positional relationship of each member will be described with reference to this XYZ orthogonal coordinate system. A predetermined direction in the vertical plane is defined as an X-axis direction, a direction orthogonal to the X-axis direction in the vertical plane is defined as a Y-axis direction, and a direction orthogonal to the X-axis direction and the Y-axis direction is defined as a Z-axis direction.

(First embodiment)
As shown in FIG. 1, the reflective screen 100 is from a projector P arranged at a position shifted in the vertical direction (Y-axis direction) with respect to the normal NL passing through the center point C of the observation surface 100 a of the reflective screen 100. The projection light Lp emitted obliquely toward the observation surface 100a is reflected to the observation side (Z-axis positive direction side) of the reflection screen 100. The reflective screen 100 is arranged so that the normal line NL is parallel to the Z axis.

  The projector P includes a mirror M that reflects the projection light Lp toward the observation surface 100 a of the reflection screen 100. Here, the position of the projector P when it is assumed that the projection light Lp is emitted from the projector P that does not include the mirror M is defined as a virtual light source position (projection unit) PV. Similarly to the projector P, the virtual light source position PV is also shifted in a direction perpendicular to the normal line NL of the observation surface 100a of the reflection screen 100.

  The projector P sets the distance D between the virtual light source position PV and the observation surface 100a to about 900 mm, and the angle θ formed between the projection light Lp and the normal NL from the virtual light source position PV toward the center point C of the reflective screen 100 is about 36 °. , An image having a vertical dimension H of about 996 mm and a horizontal dimension (X-axis direction in the figure) of W is 1771 mm can be projected onto the reflective screen 100. That is, the reflective screen 100 has a size capable of displaying an 80-inch projection image.

  As shown in FIGS. 2 and 3, the observation surface 1 a of the screen substrate 1 has a plurality of concave portions (reflecting portions) 2 each having a concave spherical surface 6 formed in a semispherical shape having substantially the same diameter. The radius of the recess 2 is, for example, about 500 μm or less and 30 μm or more. The screen substrate 1 is made of, for example, a flexible material such as resin. Further, the screen substrate 1 is formed so as to be able to absorb visible light, for example, by being colored with a black light absorbing material by staining or the like.

  In addition, the concave portions 2 are arranged in a distribution that becomes sparse according to the distance from the virtual light source position PV, and the distribution that becomes sparse by increasing the arrangement pitch as the distance from the virtual light source position PV increases. Is arranged in. More specifically, a plurality of the recesses 2 are arranged in a direction along the long side (side extending in the X direction) of the rectangular screen substrate 1 and in a direction along the short side (direction extending in the Y direction). The pitch PX and the pitch PY in the Y direction are formed so as to increase sequentially as the distance from the virtual light source position PV increases.

  As shown in FIG. 3, the inner wall surface 2 a (spherical surface 6) of the recess 2 is formed with a rough surface portion (rough surface processing portion) 20 that has been roughened so as to have a roughness that diffusely reflects the projection light Lp. Yes. As the roughness of the rough surface portion 20, the average roughness is set to 1/10 or less of the radius of the spherical surface 6, and more specifically, it is formed in the range of 10 nm to 50 μm.

  Further, the reflection film 3 that reflects the projection light Lp is formed so as to cover a part of the rough surface portion 20 along the portion of the inner wall surface 2a (spherical surface 6) irradiated with the projection light Lp from the projector P. Has been. That is, the reflective film 3 is formed only on the portion of the inner wall surface 2a of the concave portion 2 that is irradiated with the projection light Lp from the virtual light source position PV, and the reflective film 3 is formed on the other portion of the inner wall surface 2a of the concave portion 2. Instead, the light absorption surface 7 formed by the light absorption material of the screen substrate 1 is exposed (the light absorption surface 7 is also a rough surface portion 20).

The reflective film 3 formed on the inner wall surface 2a of the recess 2 is formed in a concave shape when viewed from the observation side.
The area of the reflective film 3 is formed so as to gradually decrease as it approaches the upper side in the vertical direction (Y-axis positive direction) of the observation surface 1 a of the screen substrate 1. The reflective film 3 is formed of a reflective material such as aluminum so that the film thickness is 10 nm or more and 5 μm or less by vapor deposition described later.

  On the observation surface 1 a of the screen substrate 1, a protective layer 4 that covers the reflection film 3 and the observation surface 1 a of the screen substrate 1 is formed. The protective layer 4 is made of a transparent material having flexibility, such as a resin. An antireflection layer 5 is formed on the outermost surface of the screen substrate 1 on the observation surface 1a side above the protective layer 4. The antireflection layer 5 is formed of the same material as that of the protective layer 4, and has a refractive index between the protective layer 4 and the protective layer 4 so as to prevent reflection of projection light Lp, external light, and the like on the surface 4 a of the protective layer 4. It has been adjusted. The surface of the antireflection layer 5 is an observation surface 100 a of the reflection screen 100.

Next, a method for manufacturing the screen substrate 1 having the above configuration will be described with reference to FIG.
First, as shown in FIG. 4A, a mask M is formed on a flat screen substrate 1. As this mask M, for example, chromium (Cr) is formed by sputtering or the like.
Subsequently, with respect to the mask M formed on the screen substrate 1 as described above, an opening K is formed at a position where the concave portion 2 is formed as shown in FIG. The opening K can be formed by photoetching, laser processing, or the like.

  Next, as shown in FIG. 4C, a recess 2 is formed on the surface of the screen substrate 1 by performing an etching process for a predetermined time on the screen substrate 1 on which the mask M having the opening K is formed. To do. As the etching process, either dry etching or wet etching may be employed. When wet etching is performed, for example, an ammonium monohydrogen difluoride-based one can be used.

Next, a method for performing the rough surface treatment on the spherical surface 6 of the recess 2 will be described.
The surface of the screen substrate 1 on which the concave portion 2 is formed is obtained by using spherical particles made of a metal such as cast iron or cast steel or a ceramic such as alumina or silicon carbide by a shot peening method as a rough surface treatment. Or a wet blasting method in which the projection material R is mixed with water and sprayed onto the surface of the screen substrate 1. The particle size of the projection material R can be selected from a range of 0.01 mm to 2 mm, for example, and the triple value of the standard deviation of the selected particle size is the projection material R managed within 0.005 mm. Use. By this rough surface treatment, a rough surface portion 20 having a predetermined roughness is formed on the surface of the recess 2. In addition, the particle size of these projection materials R and the spraying speed with respect to the screen board | substrate 1 are suitably adjusted so that the average roughness mentioned above may be obtained.

  In addition to the shot peening method as the rough surface treatment, for example, when the screen substrate 1 is formed of a glass substrate, the spherical surface 6 is roughened by a chemical frost method as the rough surface treatment. In this chemical frost method, the surface of the spherical surface 6 is polished into a glass or frosted shape by chemically corroding the glass substrate using a chemical such as hydrofluoric acid or hydrochloric acid.

Further, crystallized glass can be used as the glass material of the screen substrate 1. Since the surface of the crystallized glass is roughened by an etching process, the rough surface portion 20 can be formed at the same time in the step of forming the recess 2.
As the crystallized glass, for example, a substrate made of SiO ₂ —Li ₂ O—Al ₂ O ₃ glass is crystallized and the surface thereof is polished, and then an etching agent in which sulfuric acid or ammonium fluoride is added to hydrofluoric acid. What etched and formed the fine unevenness | corrugation on the surface can be used. Etching agents mainly composed of hydrofluoric acid have different etching rates for the crystallized glass crystallized layer and the amorphous layer (higher solubility in the amorphous layer), and such etchants should be used. As a result, a fine structure in which uniform crystal grains form a convex shape and are regularly distributed in the amorphous layer can be formed, and fine irregularities can be uniformly formed between the crystallized layer and the amorphous layer. Here, the depth or height of the irregularities formed on the surface of the glass substrate is controlled by conditions such as the concentration of hydrofluoric acid, the concentration of sulfuric acid or ammonium fluoride described later, and the treatment time. By adjusting these conditions, it is desirable that the depth of the irregularities be 50 to 150 angstroms.
The reason why a solution obtained by adding sulfuric acid or ammonium fluoride to hydrofluoric acid is used as an etching agent is as follows. That is, when only hydrofluoric acid is used, since the calcium fluoride or sodium silicofluoride, which is insoluble or hardly soluble in water generated by the reaction between glass and hydrofluoric acid, partially covers the glass surface, the subsequent reaction Is hindered, and the difference in partial surface roughness increases. On the other hand, when sulfuric acid is used as an additive, the sulfuric acid decomposes the aforementioned reaction product to produce a soluble salt, so that the corrosion reaction proceeds uniformly over the entire glass surface. Furthermore, since hydrofluoric acid is regenerated by such a decomposition reaction, the change over time in the concentration of hydrofluoric acid in the treatment liquid is reduced, and the difference in partial surface roughness can be reduced from both effects. Also, when ammonium fluoride is used as an additive, the reaction is accelerated because the reaction product of glass and hydrofluoric acid is decomposed and hydrofluoric acid is regenerated, as in the case of adding sulfuric acid. . In addition, since the microcrystals of ammonium silicofluoride generated by the reaction between glass and ammonium fluoride come into contact with the glass surface, very fine irregularities are formed on the substrate surface corresponding to the contact of the microcrystals. The difference in surface roughness becomes smaller.
The preferable concentration range of hydrofluoric acid in the etching agent is 0.1 to 3.0% by weight (hereinafter simply referred to as%), and the preferable concentration range of sulfuric acid and ammonium fluoride is 2. 0 to 12.0% and 1.0 to 10.0%. When the concentration of hydrofluoric acid is less than 0.1% of the whole etching agent, a sufficient etching effect cannot be exerted on the glass substrate, and when the concentration of sulfuric acid is less than 2.0%, glass and hydrofluoric acid are not used. Since the sulfuric acid cannot sufficiently decompose the water-insoluble product produced by the reaction with the reaction product, the reaction product inhibits etching and uniform unevenness is not formed. Furthermore, even when the concentration of ammonium fluoride is less than 1.0%, the corrosion reaction does not proceed uniformly as in the case of sulfuric acid, and the difference in surface roughness increases. Furthermore, when the concentration of hydrofluoric acid, sulfuric acid, or ammonium fluoride exceeds the respective upper limit values, the reaction proceeds rapidly within a short period of time, so etching is also performed during the transfer time from the etching process to the cleaning process. The surface roughness value fluctuates greatly with a slight time difference. In consideration of actual process control, it is desirable that a processing time of 10 seconds or more, more preferably 20 to 60 seconds is required until a desired surface roughness is obtained. For this purpose, the concentration of each component is set to the upper limit value or less. It is desirable to do. A more preferable concentration range of each component is 0.5 to 2% hydrofluoric acid concentration, 2 to 8% sulfuric acid concentration, and 1 to 5% ammonium fluoride concentration.
The etching treatment for the crystallized glass is described in detail in JP-A-7-296380.

  Thereafter, by removing the mask M from the screen substrate 1, the screen substrate 1 having the recesses 2 can be obtained as shown in FIG.

Next, the entire screen substrate 1 on which the recesses 2 are formed is colored black, for example, by staining.
Subsequently, a reflective film 3 is formed in the recess 2.
As shown in FIG. 3, on the observation side (Z-axis positive direction side) of the screen substrate 1, it is shifted to the lower side in the vertical direction (Y-axis negative direction side) with respect to the normal line NL of the observation surface 1 a of the screen substrate 1. The vapor deposition source S is arranged at the virtual light source position PV of the position. Then, the reflective film material is vapor-deposited obliquely with respect to the observation surface 1 a by the vapor deposition method to form the reflective film 3 on the inner wall surface 2 a of the recess 2. As the reflective film material, for example, a metal material having excellent reflectivity such as aluminum can be used.

When the reflective film 3 is formed by the vapor deposition method, the angle θs of vapor deposition of the reflective film material with respect to each concave portion 2 on the observation surface 1a is set so that the projection light Lp from the virtual light source position PV is incident on each concave portion 2 on the observation surface 1a. A vapor deposition source S having aluminum or the like as a target is disposed so as to be equal to the angle θp, and a reflective film material is vapor deposited on each concave portion 2 from the incident direction of the projection light Lp.
Note that a mask is preferably disposed on the observation surface 1a so that a reflective film is not formed.

Thereby, the concave reflective film 3 as viewed from the observation side (Z-axis positive direction side) is deposited along the portion irradiated with the projection light Lp of the inner wall surface 2a at the position facing the virtual light source position PV in the concave portion 2. The source S is formed radially on the observation surface 1a. At this time, the film thickness of the reflective film 3 is, for example, about 10 nm or more and about 5 μm or less. Further, since the rough surface portion 20 is formed on the inner wall surface 2 a, the same roughness as the rough surface portion 20 is formed on the surface of the reflective film 3 by transferring the roughness of the rough surface portion 20.
Further, by forming the reflective film 3 from the oblique direction by the vapor deposition method in this way, the film thickness of the reflective film 3 is formed so as to gradually decrease as it approaches the outer edge 3e on the non-formation region side of the reflective film 3. .
Further, by forming the reflective film 3 by vapor deposition, it is possible to form the reflective film 3 that is thinner and higher quality than the spray coating method, the printing method, and the like.

Further, by arranging the vapor deposition source S as described above and depositing the reflective film material obliquely from the incident direction of the projection light Lp, the screen substrate 1 functions as a mask and the projection light Lp of the recess 2 is irradiated. The reflective film 3 can be partially formed in accordance with the portion. Further, as the distance from the vapor deposition source S increases, the area of the inner wall surface 2a of the recess 2 where the reflective film 3 is formed is reduced, and the non-formation region (light absorption surface 7) of the reflective film 3 is enlarged.
Further, the angle θs of vapor deposition of the reflective film material with respect to the observation surface 1a is made equal to the incident angle θp of the projection light Lp from the virtual light source position PV, so that the projection light Lp from the vapor deposition source S to each recess 2 can be obtained. The difference in the area of the reflective film 3 due to the difference in the distance in the incident direction can be reduced.
Further, the degree of vacuum when forming the reflective film 3 by vapor deposition is preferably in the range of about 1 × 10 ⁻⁴ Torr to about 1 × 10 ⁻⁵ Torr, for example. By doing in this way, the roughness of the surface 3a of the formed reflecting film 3 can be raised, and a brighter projection image can be obtained.

Next, as shown in FIG. 3, the protective layer 4 is formed on the observation surface 1 a of the screen substrate 1 including the inner wall surface 2 a (spherical surface 6) of the recess 2. The protective layer 4 is formed of a material having optical transparency such as a transparent resin. Further, an antireflection layer 5 is formed on the surface of the protective layer 4. The antireflection layer 5 is formed of the same material as that of the protective layer 4, and is refracted between the protective layer 4 so that projection light Lp and external light incident on the antireflection layer 5 are not reflected on the surface of the protective layer 4. The rate has been adjusted.
As described above, according to the manufacturing method of the reflective screen 100 of the present embodiment, the reflective screen 100 as shown in FIG. 3 can be manufactured.

Next, the operation of the reflective screen 100 will be described.
As shown in FIG. 1, the projector P emits projection light Lp toward the mirror M. The projection light Lp emitted toward the mirror M is incident on the observation surface 1a of the screen substrate 1 at an angle in the same manner as the projection light Lp reflected by the mirror M and assumed to be emitted from the virtual light source position PV. . At this time, the angle θ formed between the projection light Lp incident on the center point C of the reflection screen 100 and the observation surface 100a of the reflection screen 100 is about 36 °.

The projection light Lp that has reached the observation surface 100a of the reflection screen 100 enters the antireflection layer 5 as shown in FIG. The projection light Lp incident on the antireflection layer 5 passes through the antireflection layer 5 and enters the protective layer 4. At this time, since the refractive index of the antireflection layer 5 is adjusted with respect to the protective layer 4, the projection light Lp transmitted through the antireflection layer 5 is prevented from being reflected by the surface 4 a of the protective layer 4.
The projection light Lp incident on the protective layer 4 passes through the protective layer 4 and reaches the reflective film 3 formed on the inner wall surface 2 a of the recess 2. The projection light Lp that has reached the reflective film 3 is reflected by the reflective film 3 toward the observation side of the reflective screen 100.

  Here, when the rough surface portion 20 is not provided in the concave portion 2, the projection light Lp incident on the concave portion 2 (the reflective film 3) mainly has the virtual light source position PV as shown in FIG. Only the region Ra located in the vicinity of the optical axis AX connecting the concave portion 2 contributes to the reflection to the observation side, and the peripheral region Rb separated from the optical axis AX has many as shown by the two-dot chain line arrow Ka. However, in this embodiment, since the rough surface portion 20 is provided in the concave portion 2, the projection light Lp incident on the peripheral region Rb has a rough surface as indicated by an arrow Kb. The reflection film 3 is irregularly reflected, and a part thereof is reflected on the observation side of the reflection screen 100.

  Further, as shown in FIG. 2, the recesses 2 at positions where the distance from the virtual light source position PV is large are less distributed and the number of recesses 2 is smaller than the recesses 2 at positions where the distance is small. For the concave portion 2 at a position where the distance from the virtual light source position PV is large, the area contributing to reflection to the observation side is reduced as compared with the concave portion 2 at a position where the distance from the virtual light source position PV is small. As a result, even in a situation where the projection light Lp reflected by the concave portion 2 at a position where the distance from the virtual light source position PV is small is likely to pass through to the + Y side instead of the observation side and the luminance tends to decrease, the virtual light source position PV The luminance can be suppressed also for the concave portion 2 at a position where the distance from is large.

On the other hand, in addition to the projection light Lp, outside light Lo is incident on the observation surface 100a of the reflection screen 100 from above the screen substrate 1 in the vertical direction (Y-axis positive direction side), as shown in FIG. . The external light Lo incident on the observation surface 100 a enters the antireflection layer 5, passes through the antireflection layer 5, and reaches the surface 4 a of the protective layer 4.
Here, since the antireflection layer 5 is formed on the reflection screen 100, the external light Lo incident on the observation surface 100a from above the observation surface 100a is reflected to the observation side by the surface 4a of the protective layer 4. Is prevented.

Then, the external light Lo that has reached the surface 4 a of the protective layer 4 passes through the protective layer 4 and enters the recess 2. The external light Lo incident on the recess 2 reaches the light absorption surface 7 located in the non-formation region of the reflective film 3 on the lower side of the recess 2 in the drawing.
Here, since the screen substrate 1 has the light absorption surface 7 capable of absorbing visible light as described above, the screen substrate 1 has the light absorption surface 7 in the non-formation region of the reflection film 3 on the inner wall surface 2a of the recess 2. The reached external light Lo is absorbed by the screen substrate 1 (light absorption surface 7). Even when the external light Lo is reflected, since the rough surface portion 20 is also formed on the light absorption surface 7, the external light Lo is irregularly reflected, and the amount of light reflected on the observation side can be suppressed.

Further, the external light Lo that has reached the non-formation region of the concave portion 2 of the screen substrate 1 is similarly absorbed by the screen substrate 1. Further, since the reflection film 3 is formed only on the upper side of the concave portion 2 where the projection light Lp is incident, the external light Lo is not incident on the reflection film 3.
Therefore, it is possible to prevent the external light Lo incident on the observation surface 100a of the reflective screen 100 from being reflected to the observation side.

  As described above, the antireflection layer 5 reliably causes the projection light Lp to reach the projection light Lp incident on the observation surface 100a of the reflection screen 100 from the projector P by the reflection film 3, and the reflectance of the projection light Lp. There is an effect of improving. On the other hand, with respect to the external light Lo incident on the observation surface 100a, there is an effect that the external light Lo is absorbed by the screen substrate 1 without being reflected by the protective layer 4 to the observation side. Therefore, the contrast of the reflective screen 100 can be improved by forming the antireflection layer 5 as described above.

  As described above, in the present embodiment, since the rough surface portion 20 is formed on the spherical surface 6 of the concave portion 2, when the rough surface portion 20 does not exist, a part of the projection light Lp that is not reflected to the observation side is obtained. Reflection to the observation side is possible, and reflection of external light Lo to the observation side can be suppressed, so that the contrast of the projected image can be improved and display quality can be improved. Further, when the average roughness of the rough surface portion 20 is less than 10 nm, sufficient irregular reflection cannot be obtained, and when the average roughness exceeds 50 μm, the irregular reflection of the projection light is not stable and the visibility of the image is improved. Although this may be reduced, in the present embodiment, since the average roughness is in the range of 10 nm to 50 μm, these problems can be avoided. Furthermore, when the average roughness of the rough surface portion 20 exceeds 1/10 of the radius of the spherical surface 6, the shape of the spherical surface 6 of the recess 2 may not be maintained. By setting it to 1/10 or less, it is possible to form the rough surface portion 20 while maintaining the shape of the spherical surface 6.

In the present embodiment, since the concave portions 2 are arranged in a distribution that becomes sparse according to the distance from the virtual light source position PV, the projection light Lp reflected by the concave portion 2 at a position where the distance from the virtual light source position PV is small. However, even in a situation where the ratio of coming off to the + Y side rather than the observation side is large and the luminance tends to decrease, the luminance can be suppressed even for the concave portion 2 at a position where the distance from the virtual light source position PV is large, It is possible to uniformly reflect the projection light Lp to the observation side in front of the reflection screen 100 to improve the contrast of the projection image. In particular, in the present embodiment, the concave portion 2 has the spherical surface 6, and the area for reflecting the projection light Lp to the observation side in front of the reflection screen 100 is a part thereof, so that the density of the arrangement distribution is adjusted. By doing so, it is possible to easily adjust the luminance distribution of the reflected light.
In addition, in the present embodiment, since the reflecting portion is formed in a concave shape, the projection light Lp can reach the concave portion 2 without being blocked like a convex shape, and the luminance can be improved as a whole. .

  In the present embodiment, the deposition source S is arranged at the virtual light source position PV, and the reflective film 3 is formed at the position facing the virtual light source position PV of the concave portion 2, so that the reflective film is only applied to the position irradiated with the projection light Lp. 3 and the other recesses 2 where the external light Lo is incident can be set on the light absorption surface 7, so that the external light Lo can be effectively prevented from being reflected to the observation side, and the projection quality is improved. It becomes possible.

In addition, in this embodiment, since the protective layer 4 is formed so as to cover the reflective film 3, damage and deterioration of the reflective film 3 can be prevented.
Furthermore, since the screen substrate 1 is formed of a flexible material, the flexible reflective screen 100 can be formed, the reflective screen 100 can be wound, and the reflective screen 100 can be made compact. Can be stored.

(Second Embodiment)
Next, a second embodiment of the reflective screen 100 will be described with reference to FIG.
This embodiment is different from the reflective screen 100 described in the first embodiment described above in that the projection 21 is provided on the screen substrate 11 instead of the depression 2. Since the other points are the same as in the first embodiment, the same parts are denoted by the same reference numerals and description thereof is omitted.
A reflective screen 200 shown in FIG. 6 is arranged with respect to the projector P in the same manner as the reflective screen 100 of the first embodiment shown in FIG. The screen substrate 11 of the reflective screen 200 is formed so as to be able to absorb visible light, like the screen substrate 1 of the first embodiment.

  As shown in FIG. 6, a plurality of hemispherical convex portions (reflecting portions) 21 are formed on the observation surface 11 a of the screen substrate 11. The convex portion 21 has a convex spherical surface 26 formed in a hemispherical shape, similar to the concave portion 2 shown in FIG. 2, and extends in the vertical direction (Y-axis direction) and the horizontal direction (X-axis direction) of the screen substrate 11. Multiple sequences are arranged. Similarly to the concave portion 2, the convex portions 21 are formed to have substantially the same diameter in a range of about 500 μm or less and 30 μm or more, and are arranged in a sparse distribution according to the distance from the virtual light source position PV. Further, the arrangement pitch is increased as the distance from the virtual light source position PV increases (the planar arrangement is the same as that of the recess 2 shown in FIG. 2).

  Similar to the rough surface portion 20 of the concave portion 2 in the first embodiment, the surface 21a (spherical surface 26) of the convex portion 21 has a rough surface portion (rough surface) that has been roughened so as to have a roughness that diffusely reflects the projection light Lp. 20A of surface processing parts) are formed. As the roughness of the rough surface portion 20A, the average roughness is set to 1/10 or less of the radius of the spherical surface 26, and more specifically, is formed in the range of 10 nm to 50 μm.

  A reflective film 31 similar to the reflective film 3 of the first embodiment is provided so as to cover a part of the rough surface portion 20A along the portion of the surface 21a of the convex portion 21 irradiated with the projection light Lp from the projector P. Is formed. The reflective film 31 is formed only on the portion of the surface 21 a of the convex portion 21 that is irradiated with the projection light Lp, and the reflective film 31 is not formed on the other portion of the surface 21 a of the convex portion 21. The surface 21a of the convex portion 21, which is a portion, is an exposed light absorbing surface 27 (the light absorbing surface 27 is also a rough surface portion 20A). The reflective film 31 formed on the surface 21a of the convex portion 21 is formed in a convex shape when viewed from the observation side (Z-axis positive direction side).

  A protective layer 4 similar to that of the first embodiment is formed on the observation surface 11 a side of the screen substrate 11 so as to cover the reflection film 31 and the observation surface 11 a of the screen substrate 11. Further, an antireflection layer 5 is formed on the upper surface of the protective layer 4 on the outermost surface of the screen substrate 11 on the observation surface 11a side, as in the first embodiment.

  As a method for forming the convex portion 21 on the screen substrate 11, a known method can be used. For example, as described in JP-A-2004-286906, a concave portion corresponding to the convex portion 21 is formed on the mold substrate for forming the convex portion 21 by etching or the like, and then the rough surface treatment is performed on the concave portion. The protrusion 21 can be formed by pressing and transferring a thermoplastic resin or the like to the surface of the mold substrate where the recess is formed, while applying heat.

  As a step of forming a concave portion corresponding to the convex portion 21 on the mold substrate, a procedure of forming the concave portion 2 on the screen substrate 1 and roughening the surface of the concave portion 2 shown in FIG. 4 in the first embodiment, It is the same. Specifically, referring to FIG. 4, as shown in FIG. 4A, first, a mask M is formed on a flat mold substrate P with chromium or the like. Here, a glass material is used as the mold substrate P.

  Subsequently, with respect to the mask M formed on the mold substrate P in this way, as shown in FIG. 4B, an opening K is formed at a position where the convex portion 21 is formed by photoetching, laser processing, or the like. To do. Next, as shown in FIG. 4C, a concave portion PR is formed on the surface of the mold substrate P by etching the mold substrate P on which the mask M having the opening K is formed for a predetermined time. To do. As the etching process, either dry etching or wet etching may be employed.

  Then, for the mold substrate P on which the concave portion PR is formed, the screen substrate 1 is formed by using spherical particles made of a metal such as cast iron or cast steel, or a ceramic such as alumina or silicon carbide by a shot peening method as a rough surface treatment. Or a wet blasting method in which the projection material R is mixed with water and sprayed onto the surface of the screen substrate 1. The particle size of the projection material R can be selected from a range of 0.01 mm to 2 mm, for example, and the triple value of the standard deviation of the selected particle size is the projection material R managed within 0.005 mm. Use. By this rough surface treatment, a rough surface portion 20A 'having a predetermined roughness is formed on the surface of the recess PR. In addition, the particle size of these projection materials R and the spraying speed with respect to the type | mold board | substrate P are suitably adjusted so that the average roughness mentioned above may be obtained.

In addition to the shot peening method as the rough surface treatment, for example, when the mold substrate P is formed of a glass substrate, the surface of the recess PR is roughened by a chemical frost method as the rough surface treatment. In this chemical frost method, the surface of the concave portion PR is polished and processed into a glass or frosted shape by chemically corroding the glass substrate using a chemical such as hydrofluoric acid or hydrochloric acid.
Furthermore, crystallized glass can be used as the glass material of the mold substrate P. Since the surface of the crystallized glass is roughened by an etching process, the rough surface portion 20A ′ can be simultaneously formed in the step of forming the concave portion PR.

  Then, as described above, by using the mold substrate P formed in this way, a thermoplastic resin or the like is pressed against the surface of the mold substrate P while applying heat, whereby the rough surface treatment shown in FIG. Thus, the screen substrate 11 having the plurality of convex portions 21 can be formed.

Next, as in the first embodiment, the entire screen substrate 11 is colored black by, for example, staining.
Next, similarly to the above, the vapor deposition source S is arranged at the virtual light source position PV, and the reflective film material is vapor-deposited obliquely with respect to the observation surface 11a by the vapor deposition method, thereby forming the reflective film 31 on the surface of the convex portion 21. Since the rough surface portion 20A is also formed on the surface of the convex portion 21 for the reflective film 31, the roughness of the rough surface portion 20A is transferred to the surface of the reflective film 31 as well as the rough surface portion 20A. Is formed.
The subsequent steps are the same as those in the first embodiment.

Next, the operation of this embodiment will be described.
The projection light Lp assumed to be emitted from the virtual light source position PV shown in FIG. 6 is incident on the observation surface 200a of the reflection screen 200 obliquely.
The projection light Lp that has reached the observation surface 200 a enters the antireflection layer 5. The projection light Lp incident on the antireflection layer 5 passes through the antireflection layer 5 and enters the protective layer 4.
At this time, similarly to the first embodiment, the antireflection layer 5 prevents the projection light Lp from being reflected by the surface 4 a of the protective layer 4.
The projection light Lp incident on the protective layer 4 passes through the protective layer 4 and reaches the reflective film 31 formed on the convex portion 21. The projection light Lp that has reached the reflective film 31 is reflected by the convex reflective film 31 to the observation side of the reflective screen 200.

  Here, the projection light Lp incident on the convex portion 21 is an optical axis mainly connecting the virtual light source position PV and the convex portion 21 as described above when the convex portion 21 is not provided with the rough surface portion 20A. Only the region located in the vicinity of AX contributes to the reflection on the observation side, and most of the peripheral region separated from the optical axis AX does not contribute to the reflection on the observation side. Since the rough surface portion 20 </ b> A is provided, the projection light Lp incident on the peripheral region is irregularly reflected by the reflection film 31 having a rough surface, and a part thereof is reflected to the observation side of the reflection screen 200.

  In addition, since the convex portions 21 at positions where the distance from the virtual light source position PV is large are sparser and less distributed than the convex portions 21 where the distance is small, the number of the convex portions 21 is small. For the convex portion 21 at a position where the distance from the PV is large, the area contributing to reflection on the observation side is reduced as compared with the convex portion 21 at a position where the distance from the virtual light source position PV is small. As a result, even if the projection light Lp reflected by the convex portion 21 at a position where the distance from the virtual light source position PV is small has a large ratio of passing to the + Y side instead of the observation side, the luminance is likely to decrease. Luminance can also be suppressed for the convex portion 21 at a position where the distance from the PV is large, and the same actions and effects as in the first embodiment can be obtained.

  In the present embodiment, the reflective film 31 is formed along the portion of the surface 21a of the hemispherical convex portion 21 to which the projection light Lp is irradiated. Thereby, since the shape of the reflective film 31 is formed in a convex shape when viewed from the observation surface 200a side of the reflective screen 200, the projection light Lp is more generated than in the case where the reflective film 31 is formed in a concave shape. The viewing angle of the projected image can be enlarged by reflecting the light at a wide angle.

(Third embodiment)
Next, a third embodiment of the reflective screen will be described with reference to FIG.
In this embodiment, the reflective screen 100 described in the first embodiment and the screen substrate 12 are formed of a light-transmitting material, and the concave portion 22 is formed on the surface 12b of the screen substrate 12 opposite to the observation surface 12a side. Is different in that it is formed. Since the other points are the same as in the first embodiment, the same parts are denoted by the same reference numerals and description thereof is omitted.
A reflection screen 300 shown in FIG. 7 is arranged with respect to the projector P in the same manner as the reflection screen 100 of the first embodiment shown in FIG.

  As shown in FIG. 7, the screen substrate 12 of the reflective screen 300 is formed of a material having light transmissivity and flexibility such as resin, for example. A plurality of concave portions (reflecting portions) 22 each having a concave spherical surface 36 formed in a hemispherical shape are formed on the surface 12 b opposite to the observation surface 12 a of the screen substrate 12. Similar to the recess 2 shown in FIG. 2, the recesses 22 are arranged in a sparse distribution according to the distance from the virtual light source position PV, and the arrangement pitch increases as the distance from the virtual light source position PV increases. It is arranged to be.

  On the inner wall surface 22a of the concave portion 22, a rough surface portion (rough surface processing portion) 20B that has been subjected to a rough surface treatment so as to have a roughness that diffusely reflects the projection light Lp is formed as in the rough surface portion 20 in the concave portion 2 described above. Yes. The roughness of the rough surface portion 20B is the same as that of the rough surface portion 20 described above.

  A reflection film 32 that reflects the projection light Lp is formed along the portion of the inner wall surface 22a irradiated with the projection light Lp from the projector P so that the rough surface is transferred by covering a part of the rough surface portion 20B. ing. The reflection film 32 is formed only on the portion of the inner wall surface 22a of the recess 22 where the projection light Lp is irradiated, and the reflection film 32 is not formed on the other portion of the inner wall surface 22a of the recess 22, so that the light absorption of the screen substrate 12 is achieved. The light absorption surface 37 formed of the material is exposed (the light absorption surface 37 is also a rough surface portion 20B). The reflection film 32 formed on the inner wall surface 22a of the recess 22 is formed in a convex shape when viewed from the observation side (Z-axis positive direction side). The reflective film 32 is formed of the same material and film thickness as the reflective film 3 of the first embodiment.

On the observation surface 12 a side of the screen substrate 12, an antireflection layer 51 whose refractive index is adjusted so as to prevent reflection of light on the observation surface 12 a of the screen substrate 12 is formed.
On the other hand, a light absorption layer 16 is formed of a material that absorbs light on the surface 12b of the screen substrate 12 opposite to the observation surface 12a. The light absorption layer 16 is formed using, for example, a resin colored black by dyeing or the like, or a resin containing a black pigment. The light absorption layer 16 is formed on the surface 12 b opposite to the observation surface 12 a of the screen substrate 12 including the inside of the recess 22 so as to cover the reflective film 32.

Next, the operation of this embodiment will be described.
As shown in FIG. 1, the projection light Lp is emitted from the projector P toward the mirror M, and the projection light Lp assumed to be emitted from the virtual light source position PV shown in FIG. The incident light is oblique.
The projection light Lp that has reached the observation surface 300a enters the antireflection layer 51 as shown in FIG. The projection light Lp incident on the antireflection layer 51 passes through the antireflection layer 51 and enters the screen substrate 12. At this time, the antireflection layer 51 prevents the projection light Lp from being reflected by the observation surface 12 a of the screen substrate 12.
The projection light Lp incident on the screen substrate 12 passes through the screen substrate 12 and reaches the reflection film 32 formed in the recess 22. The projection light Lp that has reached the reflection film 32 is reflected to the observation side of the reflection screen 300 by the reflection film 32 formed in a convex shape when viewed from the observation side.

  Here, similarly to the convex portion 21 shown in FIG. 6, the projection light Lp incident on the concave portion 22 (the back surface side thereof) is, as described above, when the rough surface portion 20 </ b> B is not provided in the concave portion 22. Only the region located in the vicinity of the optical axis connecting the virtual light source position PV and the concave portion 22 contributes to the reflection to the observation side, and many of the peripheral regions separated from the optical axis do not contribute to the reflection to the observation side. However, in the present embodiment, since the rough surface portion 20B is provided in the concave portion 22, the projection light Lp incident on the peripheral region is irregularly reflected by the reflection film 32 having a rough surface, and a part thereof is observed on the reflection screen 300. Reflected to the side.

In addition, the recesses 22 are arranged so that the arrangement pitch increases as the distance from the virtual light source position PV increases. Further, as described above, in the recess 22, the reflective film 32 and the light absorption layer 16 are formed on the inner wall surface 22 a of the recess 22 on the surface 12 b opposite to the observation surface 12 a of the screen substrate 12. Therefore, the reflective film 32 is formed in a convex shape when viewed from the observation surface 300a side of the reflective screen 300, and has substantially the same configuration as the convex portion 21 and the reflective film 31 described in the second embodiment. .
That is, the external light Lo incident on the non-formation region of the reflective film 32 in the concave portion 22 is absorbed by the light absorption layer 16 filled in the concave portion 22, and the external light Lo is prevented from being reflected on the observation side of the reflective screen 300. can do. Even when the external light Lo is reflected by the concave portion 22, the rough surface portion 20B is formed, so that the external light Lo is irregularly reflected, and the amount of light reflected to the observation side can be suppressed.
Further, the projection light Lp is allowed to pass between the recesses 22 and 22 adjacent to the reflection screen 300 in the horizontal direction (projections as viewed from the observation surface 300a side) and incident on the reflection film 32 of the recess 22 adjacent in the vertical direction. Can be made.

  Therefore, according to the present embodiment, it is possible to obtain the same effect as that of the second embodiment described above. In addition, since the screen substrate 12 itself functions in the same manner as the protective layer 4 in the second embodiment, it is not necessary to form the protective layer 4, simplifying the manufacturing process of the reflective screen 300, and improving productivity. it can.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described with reference to FIG.
In this embodiment, the reflective screen 100 described in the first embodiment and the screen substrate 13 are formed of a light-transmitting material, and a convex portion (on the surface 13b opposite to the observation surface 13a of the screen substrate 13 ( This is different in that a reflection portion 23 is formed. Since the other points are the same as in the first embodiment, the same parts are denoted by the same reference numerals and description thereof is omitted. A reflection screen 400 shown in FIG. 8 is arranged in the same manner as the reflection screen 100 of the first embodiment shown in FIG.

  The screen substrate 13 of the reflective screen 400 is made of a material having light transmissivity and flexibility such as resin, for example. On the surface 13b of the screen substrate 13 opposite to the reflection observation surface 13a, a plurality of convex portions 23 having convex spherical surfaces 46 formed in a hemispherical shape having substantially the same diameter are formed. As with the concave portion 2 shown in FIG. 2, the convex portions 23 are arranged in a distribution that becomes sparse according to the distance from the virtual light source position PV, and the arrangement pitch increases as the distance from the virtual light source position PV increases. It is arranged to be larger.

  On the surface 23a of the convex portion 23, similarly to the rough surface portion 20A of the convex portion 21 in the second embodiment, a rough surface portion (rough surface processing portion) that has been roughened so as to have a roughness that diffusely reflects the projection light Lp. 20C is formed. The roughness of the rough surface portion 20C is the same as that of the rough surface portion 20A.

  A rough surface is transferred by covering a part of the rough surface portion 20C with a reflection film 33 that reflects the projection light Lp along a portion of the surface 23a of the convex portion 23 that is irradiated with the projection light Lp from the projector P. It is formed in a state. That is, as shown in FIG. 8, the reflective film 33 is formed only on the portion irradiated with the projection light Lp on the surface 23a of the convex portion 23, and the reflective film 33 is formed on the other portion of the surface 23a of the convex portion 23. Instead, the light absorption surface 47 formed by the light absorption material of the screen substrate 13 is exposed (the light absorption surface 47 is also a rough surface portion 20C).

The reflective film 33 formed on the surface 23a of the convex portion 23 is formed in a concave shape when viewed from the observation side (Z-axis positive direction side). The reflective film 33 is formed of the same material and thickness as the reflective film 3 in the first embodiment.
An antireflection layer 51 similar to that of the third embodiment is formed on the observation surface 13 a of the screen substrate 13. On the other hand, on the surface 13b of the screen substrate 13 opposite to the observation surface 13a, a light absorption layer 16 similar to that of the third embodiment is formed so as to cover the convex portion 23 and the reflective film 33.

Next, the operation of this embodiment will be described.
The projection light Lp is emitted from the projector P toward the mirror M, and is incident obliquely on the observation surface 400a of the reflection screen 400, similarly to the projection light Lp emitted from the virtual light source position PV shown in FIG.
The projection light Lp that has reached the observation surface 400 a enters the antireflection layer 51. The projection light Lp incident on the antireflection layer 51 passes through the antireflection layer 51 and enters the screen substrate 13. At this time, the antireflection layer 51 prevents the projection light Lp from being reflected by the observation surface 13 a of the screen substrate 13.
The projection light Lp incident on the screen substrate 13 passes through the screen substrate 13 and reaches the reflection film 33 formed on the surface 23 a of the convex portion 23. The projection light Lp reaching the reflection film 33 is reflected to the observation side of the reflection screen 400 by the reflection film 33 formed in a concave shape when viewed from the observation side of the reflection screen 400.

  Here, as in the case of the concave portion 2 shown in FIG. 5, the projection light Lp incident on the convex portion 23 (the back side thereof), when the convex portion 23 is not provided with the rough surface portion 20C, as described above, Only the region mainly located in the vicinity of the optical axis connecting the virtual light source position PV and the convex portion 23 contributes to the reflection to the observation side, and most of the peripheral region separated from the optical axis is reflected to the observation side. Although not contributing, in this embodiment, since the rough surface portion 20C is provided on the convex portion 23, the projection light Lp incident on the peripheral region is irregularly reflected by the reflection film 33 having a rough surface, and a part of the reflection light is reflected on the reflection screen. Reflected to 400 viewing side.

Further, the convex portions 23 are arranged so that the arrangement pitch increases as the distance from the virtual light source position PV increases so that the convex portions 23 are arranged in a sparse distribution according to the distance from the virtual light source position PV. . Moreover, the convex part 23 is formed in the surface 13b on the opposite side to the observation surface 13a of the screen board | substrate 13 as mentioned above, and the reflecting film 33 and the light absorption layer 16 are formed in the surface 23a. For this reason, the reflective film 33 is formed in a convex shape when viewed from the observation surface 400a side of the reflective screen 400, and has substantially the same configuration as the concave portion 2 described in the first embodiment.
That is, external light incident on the non-formation region of the reflective film 33 of the convex portion 23 is absorbed by the light absorption layer 16 that covers the surface 23 a of the convex portion 23, and the external light Lo is reflected to the observation side of the reflective screen 400. Can be prevented. Even when the external light Lo is reflected by the convex portion 23, the rough surface portion 20C is formed. Therefore, the external light Lo is irregularly reflected, and the amount of light reflected to the observation side can be suppressed.

  Therefore, according to the reflective screen 400 of the present embodiment, not only the same effect as the reflective screen 100 of the first embodiment is obtained, but it is not necessary to form the protective layer 4 as in the third embodiment. The manufacturing process of the reflective screen 400 can be simplified and the productivity can be improved.

  As described above, the preferred embodiments according to the present invention have been described with reference to the accompanying drawings, but the present invention is not limited to the examples. Various shapes, combinations, and the like of the constituent members shown in the above-described examples are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

  For example, as long as the shape of the concave portion or the convex portion has a spherical surface, it is not a hemispherical shape as described in the above-described embodiment, but a semi-elliptical spherical shape, a conical shape, a fan shape, or a combination thereof. These shapes are also included in the spherical surface.

Moreover, in the said embodiment, although it was set as the structure which forms a rough surface part in the whole surface of the recessed parts 2 and 22 and the convex parts 21 and 23, it is not limited to this, For example, the front view of FIG. 9 and the cross section of FIG. As shown in the figure, the central portion of the spherical surface 6 of each recess 2 may be a smooth surface portion 40 and the rough surface portion 20 may be formed only at the peripheral edge portion.
In this configuration, the amount of the projection light Lp reflected to the observation side in the smooth surface portion 40 increases, and the rough surface portion 20 generates the projection light Lp even if it is a peripheral portion that is difficult to contribute when reflecting to the front observation side. By irregularly reflecting, part of the projection light can be reflected to the observation side, and the contrast of the projection image can be improved and display quality can be improved.

Furthermore, it is not the structure which partitions and provides a rough surface part and a smooth surface part in each recessed part or each convex part, for example, as shown in FIG. 11, the rough surface part 20 is provided in the recessed part 2 located in the peripheral part of the screen substrate 1, It is good also as a structure which provides the smooth surface part 40 in the recessed part 2 located in the center side.
In this configuration, the amount of the projection light Lp reflected to the observation side increases in the concave portion 2 located on the center side, and even at the peripheral portion of the screen substrate 1 that is difficult to contribute when reflecting to the front observation side, When the rough surface portion 20 irregularly reflects the projection light Lp, a part of the projection light can be reflected to the observation side, and the contrast of the projection image can be improved and display quality can be improved. Also in this configuration, the center portion of the spherical surface 6 may be the smooth surface portion 40 and the rough surface portion 20 may be formed only in the peripheral portion for each recess 2 located in the peripheral portion of the screen substrate 1.

Further, when the concave portion 2 having the rough surface portion 20 is disposed in the peripheral portion of the screen substrate 1, the radius of the concave portion 2 (spherical surface) having the rough surface portion 20 is the radius of the concave portion 2 not having the rough surface portion 20. It is good also as a structure formed with a bigger radius.
In this configuration, the spherical surface is increased in diameter to approach the plane, and even the projection light Lp irradiated to the peripheral portion of the screen substrate 1 can further increase the amount of the projection light Lp reflected to the observation side. It becomes possible.

Further, the concave portions or the convex portions are arranged so that the arrangement pitch increases as the distance from the virtual light source position PV increases, so that the concave portions or the convex parts are arranged in a sparse distribution according to the distance from the virtual light source position PV. In this case, the planar arrangement is a configuration arranged on a straight line extending radially from the virtual light source position PV, a configuration arranged sequentially from an edge on the −Y side of the screen substrate, or a flat staggered arrangement. It may be a thing.
Furthermore, if the distribution is sparse according to the distance from the virtual light source position PV, it is not necessary to arrange the distribution uniformly. For example, the reflection distribution of the projection light Lp from the observation surface is biased. Alternatively, the reflection distribution (luminance distribution) may be corrected by adjusting the arrangement distribution of the regions having the bias.

  In addition, as described in the above embodiment, the entire screen substrate is not colored by staining, but only a part of the observation surface side is colored, or only the observation surface is painted black to form a light absorption film. It may be provided.

  In the above embodiment, when the reflective film is formed, the vapor deposition source is arranged at the virtual light source position PV and vapor deposition is performed in a radial manner. However, the present invention is not limited to this. For example, a rectangular vapor deposition source is used as the screen. It is good also as a structure arrange | positioned in parallel along the edge on the -Y side of a board | substrate, and vapor-depositing in a line form.

It is sectional drawing which shows the positional relationship of the reflective screen which concerns on 1st Embodiment of this invention, and a projector. It is a front view of the reflective screen which concerns on 1st Embodiment of this invention. It is sectional drawing of the perpendicular direction of the reflective screen which concerns on 1st Embodiment of this invention. It is a figure which shows the procedure which manufactures the screen board | substrate 1. FIG. It is sectional drawing of the perpendicular direction of the reflective screen which concerns on 1st Embodiment of this invention. It is sectional drawing of the perpendicular direction of the reflective screen which concerns on 2nd Embodiment of this invention. It is sectional drawing of the perpendicular direction of the reflective screen which concerns on 3rd Embodiment of this invention. It is sectional drawing of the perpendicular direction of the reflective screen which concerns on 4th Embodiment of this invention. It is a front view of the reflective screen which concerns on another form of this invention. It is sectional drawing of the perpendicular direction of the reflective screen which concerns on the same form. It is a front view of the reflective screen which concerns on another form of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1, 11, 12, 13 ... Screen substrate, 2, 22 ... Recessed part (reflective part), 3, 31, 32, 33 ... Reflective film, 4 ... Protective layer, 5, 51 ... Antireflection layer, 6, 26, 36 , 46 ... spherical surface, 7, 27, 37 ... light absorbing surface, 20, 20A, 20B ... rough surface part (rough surface processing part), 21, 23 ... convex part (reflective part), 100, 200, 300 ... reflective screen 100a, 200a ... observation surface, Lp ... projection light, NL ... normal, PV ... virtual light source position (projection unit)

Claims (26)

Projection light emitted obliquely toward the observation surface from a projection unit that has a plurality of reflection portions on the observation surface of the screen substrate and is arranged at a position shifted in a direction perpendicular to the normal line of the observation surface Is a reflective screen that reflects to the viewing side,
The reflecting portion has a concave or convex spherical surface,
Wherein at least a portion of the spherical surface, have a rough surface section which is roughened to a predetermined roughness to diffuse the projected light,
The rough surface treatment portion is provided at a peripheral edge of the spherical surface,
The reflective screen according to claim 1, wherein the rough surface treatment portion is provided only at a peripheral portion of the spherical surface, and a smooth surface portion is provided at a central portion of the spherical surface . Projection light emitted obliquely toward the observation surface from a projection unit that has a plurality of reflection portions on the observation surface of the screen substrate and is arranged at a position shifted in a direction perpendicular to the normal line of the observation surface Is a reflective screen that reflects to the viewing side,
The reflecting portion has a concave or convex spherical surface,
Wherein at least a portion of the spherical surface, have a rough surface section which is roughened to a predetermined roughness to diffuse the projected light,
The rough surface treatment portion is provided at a peripheral edge of the spherical surface,
The rough surface treatment unit is provided in at least a part of the reflection unit disposed in the peripheral part of the screen substrate,
The reflective portion is reflective screen, characterized in Rukoto that having a said rough surface processing portion spherical surface formed by the larger diameter of the reflecting portion having no having the rough surface section. The reflective screen according to claim 1 or 2 ,
The reflective screen according to claim 1, wherein the rough surface treatment unit is formed in an average roughness of 10 nm to 50 μm. The reflective screen according to claim 3 .
The average roughness of the rough surface treatment unit is 1/10 or less of the radius of the spherical surface. The reflective screen according to any one of claims 1 to 4 ,
The reflective screen according to claim 1, wherein a radius of the spherical surface of the reflective portion is formed in a range of 30 μm to 500 μm. In the reflective screen as described in any one of Claim 1 to 5 ,
The reflection screen according to claim 1, wherein the reflection units are arranged in a sparse distribution as the distance from the projection unit increases. The reflective screen according to any one of claims 1 to 6 ,
The reflection unit has a reflection film on a surface facing the projection unit, and a light absorption surface in a non-formation region of the reflection film. In the reflective screen as described in any one of Claim 1 to 7 ,
A reflective screen, wherein a protective layer is provided on the observation surface side of the screen substrate. The reflective screen according to any one of claims 1 to 8 ,
The screen substrate is formed of a light transmissive material,
The reflective spherical screen is characterized in that the concave spherical surface is formed in a concave portion provided on a surface of the screen substrate opposite to the observation surface. The reflective screen according to any one of claims 1 to 8 ,
The screen substrate is formed of a light transmissive material,
The reflective screen is characterized in that the convex spherical surface is formed on a convex portion provided on a surface of the screen substrate opposite to the observation surface. The reflective screen according to any one of claims 1 to 10 ,
A reflection screen, wherein an antireflection layer is provided on the observation surface side of the screen substrate. The reflective screen according to any one of claims 1 to 11 ,
A reflective screen, wherein the screen substrate is made of a flexible material. Projection light emitted obliquely toward the observation surface from a projection unit that has a plurality of reflection portions on the observation surface of the screen substrate and is arranged at a position shifted in a direction perpendicular to the normal line of the observation surface Is a method of manufacturing a reflective screen that reflects to the viewing side,
The reflecting portion has a concave or convex spherical surface,
Wherein at least a portion of the spherical surface, have a surface roughening step of roughening so as to have a predetermined roughness to diffuse the projected light,
The rough surface treatment portion is provided at the peripheral edge of the spherical surface,
The method for producing a reflective screen, wherein the rough surface treatment portion is provided only at a peripheral portion of the spherical surface, and a smooth surface portion is provided at a central portion of the spherical surface . Projection light emitted obliquely toward the observation surface from a projection unit that has a plurality of reflection portions on the observation surface of the screen substrate and is arranged at a position shifted in a direction perpendicular to the normal line of the observation surface Is a method of manufacturing a reflective screen that reflects to the viewing side,
The reflecting portion has a concave or convex spherical surface,
A rough surface treatment step of roughening at least a part of the spherical surface to have a predetermined roughness for irregularly reflecting the projection light;
The rough surface treatment portion is provided at the peripheral edge of the spherical surface,
The rough surface treatment portion is provided on at least a part of the reflection portion disposed in the peripheral portion of the screen substrate,
Method for producing a reflective screen characterized that you formed with the said reflecting portion having a rough surface processing unit, a spherical surface having a diameter larger than that of the reflective portion having no said rough surface processing unit. In the manufacturing method of the reflective screen of Claim 13 or 14 ,
The method for producing a reflective screen, wherein the rough surface treatment portion is formed with an average roughness in a range of 10 nm to 50 μm. In the manufacturing method of the reflective screen of Claim 15 ,
An average roughness of the rough surface treatment section is 1/10 or less of a radius of the spherical surface. In the manufacturing method of the reflective screen as described in any one of Claim 13 to 16 ,
A method of manufacturing a reflective screen, wherein a radius of the spherical surface of the reflective portion is formed in a range of 30 μm to 500 μm. In the manufacturing method of the reflective screen as described in any one of Claim 13 to 17 ,
The method for manufacturing a reflective screen, wherein the rough surface treatment step includes a step of roughening a transfer surface onto which the reflective portion of the mold substrate is transferred. The method of manufacturing a reflective screen according to claim 18 .
A reflective screen manufacturing method, wherein at least a part of the transfer surface is roughened by a shot blasting method. The method of manufacturing a reflective screen according to claim 18 .
A method for producing a reflective screen, wherein at least a part of the transfer surface is roughened by a chemical frost method. The method of manufacturing a reflective screen according to claim 18 .
A method for producing a reflective screen, characterized in that crystallized glass is used as the mold substrate, and at least part of the transfer surface is roughened by etching the crystallized glass. In the manufacturing method of the reflective screen as described in any one of Claim 13 to 21 ,
A method of manufacturing a reflective screen, wherein the reflective portions are arranged with a sparse distribution as the distance from the projection portion increases. In the manufacturing method of the reflective screen of Claim 22 ,
The method for manufacturing a reflective screen, wherein the arrangement distribution of the reflection portions is adjusted according to the reflection distribution of the projection light from the observation surface. In the manufacturing method of the reflective screen as described in any one of Claim 13 to 23 ,
Forming a light absorption surface at least on the observation surface side of the screen substrate;
And a step of forming a reflective film on a surface of the reflecting portion facing the projection portion. The method of manufacturing a reflective screen according to claim 24 ,
A method for manufacturing a reflective screen, comprising: depositing a vapor deposition source having a target on the projection unit; and depositing the target on a surface of the reflection unit facing the projection unit. In the manufacturing method of the reflective screen as described in any one of Claim 13 to 25 ,
A method of manufacturing a reflective screen, comprising a step of providing a protective layer on the observation surface side of the screen substrate.

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