JP2006084769A - Stacked optical control component and projection screen using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projection screen for ensuring bright and high-quality images over a large viewing angle. <P>SOLUTION: The optical control component is built by stacking three optical control films having cloudiness which depends on the angle and having a ≥60 % light scattering angle over ≥30° of the whole area when irradiated with light at 0-180° to the surface. Two of the optical control films are stacked in a manner that their light scattering angle ranges deviate in the normal direction, and their scattering angle directions are almost parallel with each other but opposite to each other keeping the normal direction at the center. These two optical control films are in a state that their light scattering angle ranges partly overlap each other. Further, the other film has its light scattering angle range approximately matching the normal direction and is stacked in a manner that its light scattering angle range is approximately parallel with the other two films. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a light control film laminate and a projection screen using the same.

  The projection display is also called a rear projection display device, and an example thereof will be described with reference to FIG. As shown in this figure, the projection display 1 projects light from the light source unit 3 to the mirror 6 through the image display unit 4 and the projection lens 5 and reflects the light on the screen 7 to project an image from the back side. is there. For the image display unit 4, a liquid crystal panel, a cathode ray tube (CRT), or the like is used. There is also a method of directly projecting an image from the image display unit onto a screen.

  As a screen 7 of such a projection display, a combination of a Fresnel lens and a lenticular lens is usually used. The Fresnel lens has the function to change the light from the light source or the mirror into parallel light and to make it incident on the lenticular lens almost perpendicularly, while the lenticular lens controls and scatters the light incident from the Fresnel lens. It has a function to make it.

  Transparent thermoplastic resin such as acrylic resin, polystyrene resin, polyvinyl chloride resin, polycarbonate resin can be used as the material of lenticular lens and Fresnel lens of projection screen. Among them, acrylic resin is transparent, It is often used taking advantage of its hardness, durability, and processability. In addition, lenticular lenses are widely used in which light diffusibility is imparted by mixing light diffusive substances such as silica, alumina, clay, glass, and beads with the above thermoplastic resin.

  In a projection screen, both light diffusion performance and light transmission performance are important. Although the conventional projection screen is excellent in light diffusibility, it has a problem that the screen screen becomes dark because the total light transmittance is low. If you try to increase the total light transmittance in order to brighten the screen screen, the light diffusivity is sacrificed and the resolution of the screen screen decreases. It was difficult to satisfy at the same time. Further, the conventional projection screen has a problem that a moire pattern due to the pitch of the Fresnel lens and the lenticular lens is likely to occur on the screen. Furthermore, the angle range that gives an image with good visibility is narrow, and it is not satisfactory as a TV screen for large-sized high image quality.

  In order to improve these problems, several proposals have been made to apply a light control film having an angle dependency on the haze to a projection screen. For example, in Japanese Patent No. 2838295 (Patent Document 1), a composition having at least two kinds of photopolymerizable monomers or oligomers having different refractive indexes is cured by irradiating light from two or more directions. JP-A-4-77728 (Patent Document 2) describes that a light control film having an angle dependency on the haze value is applied to a projection screen. Stacking a plurality of light control films that are angle-dependent on the haze value formed by irradiating light to a composition having two types of photopolymerizable monomers or oligomers, and applying it to a projection screen Is described.

  Further, a composition containing at least two kinds of photopolymerizable monomers or oligomers having a difference in refractive index is formed into a film and cured by irradiating light from a specific direction, and the haze value is angle-dependent. For example, Japanese Patent Publication No. 7-58361 (Patent Document 3), Japanese Patent No. 2691543 (Patent Document 4), Japanese Patent No. 2702521 (Patent Document 5) Patent No. 2782200 (Patent Literature 6), Patent No. 2782250 (Patent Literature 7), Patent No. 2822065 (Patent Literature 8), Patent No. 3211381 (Patent Literature 9), etc. .

Japanese Patent No. 2838295 JP-A-4-77728 Japanese Patent Publication No. 7-58361 Japanese Patent No. 2691543 Japanese Patent No. 2702521 Japanese Patent No. 2782200 Japanese Patent No. 2782250 Japanese Patent No. 2822065 Japanese Patent No. 3211381

  If the light control film proposed in these documents is applied to a projection screen, a bright image can be obtained while maintaining a high total light transmittance. However, it has not yet been fully satisfactory in terms of providing high-quality images over a wide angle range for large televisions.

  As a result of intensive investigations in view of the problems in the current mainstream screens using a combination of Fresnel lenses and lenticular lenses and the screens using light control films proposed in the above documents, the present inventors have reached the present invention. Is. Accordingly, an object of the present invention is to provide a light control film that can provide a bright and high-quality image over a wide angle range when applied to a projection screen.

  Therefore, according to the present invention, the haze value has an angle dependency, and when the light is incident on the surface at an angle of 0 to 180 °, the light scattering angle region showing a haze value of 60% or more is 30. It is a light control film laminate formed by laminating three or more light control films that are at least °, and two of the light control films are in a direction in which the light scattering angle region is biased with respect to the normal direction, The direction of the light scattering angle range is substantially parallel to each other, the light scattering angle range is opposite to each other around the normal direction, and a part of the light scattering angle range is stacked so as to overlap each other. The other sheet is laminated so that the center of the light scattering angle region is substantially coincident with the normal direction and the direction of the light scattering angle region is substantially parallel to the previous two light control films. A light control film laminate is provided.

  In this laminated body, the light control film can be obtained by irradiating light to a composition containing at least two kinds of photopolymerizable monomers or oligomers having different refractive indexes. Further, in this laminate, it is effective that the two light control films whose light scattering angle regions are biased with respect to the normal direction overlap each other by 5 ° or more. It is also effective that the light scattering angle regions are mutually targeted around the normal direction. And this laminated body is applied suitably for the screen for projection.

  In this specification, “substantially” in the case of “substantially parallel” or “substantially coincide” means that up to about ± 10 ° is allowed around the arrangement (parallel or coincidence) described therein. To do.

  By applying the light control film laminate of the present invention to a projection screen, a bright and high-quality image can be obtained over a wide angle range.

  Hereinafter, the present invention will be described in detail. In the present invention, three or more light control films having a haze value that is angle-dependent and exhibiting a haze value of 60% or more over an angle range of 30 ° or more, that is, a light control film having a wide light scattering angle range are laminated. The light control film laminate is used. The haze here refers to the entire light control film using an integrating sphere type light transmittance measuring device (for example, a haze meter HGM-2DP type measuring device manufactured by Suga Test Instruments Co., Ltd.) according to JIS K 7105. The light transmittance and diffuse transmittance are measured, and the values are obtained by the following formula.

  Further, the angle dependency of the haze value in the light control film is measured as follows. That is, as shown in FIG. 2, the angle θ of the incident light to the test piece 8 of the light control film is changed between 0 to 180 °, and the above-described haze value is measured for each angle, and 60% or more An angle range indicating the haze value of the light is defined as a light scattering angle region. Here, the angle θ is a value in which the direction parallel to the surface of the test piece 8 is 0 ° and the normal direction of the test piece 8 is 90 °, and the rotation of the test piece 8 depends on the angle dependency of the haze value. In the direction that maximizes. A and B in the figure are the left figure (when light enters the test piece 8 from the vertical direction: θ = 90 °) and the right figure (when light enters the test piece 8 from an oblique direction) Thus, the reference numerals are attached so that the corresponding portions of the test piece 8 can be seen.

  In the present invention, a light control film having a light scattering angle range of 30 ° or more showing a haze value of 60% or more thus obtained is used. Preferably, a light control film having a light scattering angle region of 40 ° or more, particularly 45 ° or more is used. Even if this light scattering angle region is too large, the viewing angle is widened, but the front luminance is lowered, so it is usually within 100 °.

For example, as described in Patent Documents 3 to 9, such a light control film is formed by forming a composition containing at least two types of photopolymerizable monomers or oligomers having different refractive indexes into a film shape. It can be manufactured by irradiating light from a specific direction and curing it. The photopolymerizable monomer or oligomer used for the production of the light control film includes an acryloyl group [CH ₂ = CHCO-], a methacryloyl group [CH ₂ = C (CH ₃ ) CO-], a vinyl group [CH ₂ = CH-], a compound having at least one polymerizable group such as an allyl group [CH ₂ = CHCH _2- ].

  Examples of the monomer include tetrahydrofurfuryl acrylate, ethyl carbitol acrylate, dicyclopentenyloxyethyl acrylate, phenyl carbitol acrylate, nonylphenoxyethyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate, and ω-hydroxyhexanoyloxyethyl acrylate. , Acryloyloxyethyl succinate, acryloyloxyethyl phthalate, tribromophenoxyethyl acrylate, isobornyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, 2,2,3,3-tetrafluoropropyl acrylate, and their monofunctionality Methacrylate corresponding to acrylate, N-vinylpyrrolidone, triallyl isocyanurate DOO, diethylene glycol diallyl carbonate, such as di-arylidene pentaerythritol.

  In addition, as the oligomer, for example, polyfunctional acrylates such as polyester acrylate, polyol polyacrylate, modified polyol polyacrylate, polyacrylate of isocyanuric acid skeleton, melamine acrylate, hydantoin skeleton polyacrylate, polybutadiene acrylate, epoxy acrylate, urethane acrylate, The methacrylate etc. corresponding to these acrylates are mentioned.

  These photopolymerizable monomers or oligomers are used as a composition comprising at least two kinds of mixtures. At this time, one having a difference in refractive index is selected. An area that scatters light, that is, a light scattering angle area, is formed by irradiating and curing light from a predetermined direction on a composition in which at least two kinds of photopolymerizable monomers or oligomers having different refractive indexes are mixed. The This composition expresses the angle dependency of the haze value due to the mutual solubility of each of a plurality of composing compounds and the difference in the respective refractive indexes. When the reaction rate is different, the degree of light scattering, that is, the haze value increases. This refractive index difference is preferably 0.01 or more, particularly 0.04 or more.

  In order to improve curability, this composition is usually mixed with a photopolymerization initiator and subjected to photopolymerization. Examples of the photopolymerization initiator include benzophenone, benzyl, Michler's ketone, 2-chlorothioxanthone, 2,4-diethylthioxanthone, benzoin methyl ether, benzoin ethyl ether, diethoxyacetophenone, benzyldimethyl ketal, and 2-hydroxy-2-methyl. Examples include propiophenone and 1-hydroxycyclohexyl phenyl ketone.

  Such a photocurable resin composition containing at least two types of monomers or oligomers having a difference in refractive index is coated on a substrate or enclosed in a cell to form a film, and light is emitted from a rod-shaped light source. By gradually curing while irradiating, it is possible to obtain a light control film that scatters incident light in a selective angle region and transmits it in other angle regions. The light used for curing may have any wavelength as long as it cures the composition, and for example, visible light, ultraviolet light, and the like are often used. Ultraviolet rays are emitted from mercury lamps, metal halide lamps, etc. When a rod-shaped lamp is used, the generated photocured film can be adjusted with respect to the major axis and minor axis direction of the light source by adjusting the irradiation conditions. Anisotropy is exhibited, and light of a specific angle is scattered only when the light source is rotated about the major axis direction of the light source.

  In other words, the photocured film produced has a phase difference between resins having different refractive indexes to form a diffraction grating layer structure in a specific direction, and light incident from a specific angle is subject to Bragg diffraction conditions. It is considered that the light is scattered on the same principle. The degree of scattering and the angle of selectively scattered incident light can be adjusted depending on the composition used and the irradiation conditions, and in particular, by changing the incident angle of the irradiated light on the film-like composition sample surface during curing, When the light incident on the cured sheet exits from the sheet, the angle range with respect to the sheet film surface through which the light is scattered or straightly transmitted can be controlled.

  At the time of photocuring, a light scattering angle region is developed around the light irradiation direction. For example, if light is irradiated almost perpendicularly to the film surface formed from the photocurable resin composition, a light scattering angle region appears around the normal direction, that is, the normal direction, and the normal direction is If light is irradiated from an oblique direction inclined at a predetermined angle, a light scattering angle region is developed around the inclined direction.

  An example in the case of irradiating light from the perpendicular direction to the photocurable resin composition film will be described with reference to FIG. (A) of FIG. 3 is a side view schematically showing an example of an apparatus that can be used when light is irradiated from the vertical direction to the photocurable resin composition film. It is a perspective view of an apparatus. This apparatus includes a conveyor 10 that moves in the direction of a hollow arrow, a light shielding plate 12 that is disposed above the conveyor 10 and has slits 13 formed in the width direction of the conveyor, and a bar-like shape that is further spaced apart by a predetermined distance. It comprises a light source lamp 15. The slit 13 is formed so as to coincide with the length direction of the light source lamp 15. Then, the substrate 20 on which the photocurable resin composition film is formed is placed on the conveyor 10 and light is transferred from the light source lamp 15 through the slit 13 of the light shielding plate 12 while moving at a constant speed. When the film is irradiated, light in the vertical direction is centered in the composition film, so phases with different refractive indexes are alternately formed in the vertical direction (normal direction), and the light scattering angle is centered on that direction. The area will be expressed. An angular range in which the haze value increases by controlling the width of the slit 13, the distance from the rod-shaped light source lamp 15 to the photocurable resin film, the thickness of the photocurable resin film, the amount of irradiation light, the wavelength of irradiation light, and the like. That is, the size of the light scattering angle region can be controlled.

  Next, the example in the case of irradiating light from the diagonal direction with respect to a photocurable resin composition film | membrane is demonstrated based on FIG. (A) of FIG. 4 is a side view schematically showing an example of an apparatus that can be adopted when irradiating light from an oblique direction to the photocurable resin composition film. It is a perspective view of an apparatus. This apparatus comprises a conveyor 10 that moves in the direction of a hollow arrow, a light shielding plate 12 that covers a predetermined position above the conveyor 10, and a bar-like light source lamp 15 that is disposed above the conveyor 10 at a predetermined distance. The light-shielding plate 12 in this example slightly protrudes from the position immediately below the light source lamp 15 toward the traveling direction side of the conveyor 10. And if the board | substrate 20 with which the photocurable resin composition film | membrane was formed is mounted on the conveyor 10, and the light from the light source lamp 15 is irradiated toward the light-shielding plate 12 side, moving at a fixed speed, it will be predetermined. Since the light having the angle α is centered on the composition film, phases having different refractive indexes are alternately formed in the incident direction of the light, and the light scattering angle region is developed around the direction. . By changing the light irradiation angle α, the center value of the light scattering angle region can be changed, and the distance from the light source lamp 15 to the photocurable resin film, the thickness of the photocurable resin film, the amount of irradiation light By controlling the wavelength of the irradiation light, the angle range in which the haze value increases, that is, the size of the light scattering angle region can be controlled.

  In the present invention, the light control film laminate is obtained by laminating three or more light control films obtained by the method as described above and having a light scattering angle range of 30 ° or more showing a haze value of 60% or more. And Here, two of the light control films are in a direction in which the light scattering angle region is deviated from the normal direction, and the two light control films are substantially parallel to each other in the direction of the light scattering angle region. Lamination is performed so that the light scattering angle regions are opposite to each other about the normal direction, so that the light scattering angle region in the laminated state is wider than when one sheet is used. By doing so, when the obtained light control film laminate is applied to a projection screen, a good visual recognition area in the left-right or vertical direction, that is, a viewing angle can be expanded. Further, the two light control films are in a state in which a part of the light scattering angle region overlaps each other, so that when the obtained light control film stack is applied to a projection screen, a bright image is displayed in front of the screen. Can be obtained.

  Furthermore, another one of the light control films has the center of the light scattering angle region substantially coincided with the normal direction, and this light control film is separated from the previous two light control films by the light scattering angle region. The layers are laminated so that the directions are substantially parallel. In this way, when the obtained light control film laminate is applied to a projection screen, a brighter image can be obtained in front of the screen.

  As a method of laminating the light control film, separately prepared light control films may be bonded through a medium such as an adhesive, or may be stacked without using a medium. In addition, the light control film can be laminated by applying the photocurable resin composition on the produced light control film itself as a base material and curing it to form another light control film. Can do.

  An example of obtaining the light control film laminate of the present invention by laminating the three light control films will be described with reference to FIG. In this example, it is assumed that the first light control film 21 exhibits a haze value of 60% or more in an angle β range in a direction slightly deviated to the right from the normal direction. On the other hand, the second light control film 22 exhibits a haze value of 60% or more in the range of the angle β in a direction slightly deviated to the left from the normal direction. These angles β correspond to the light scattering angle region. The direction in which the light scattering angle region extends is referred to as “light scattering angle region direction”. The second light control film 22 corresponds to a state in which the direction of the first light control film 21 is reversed (a state in which the left and right are reversed in this drawing). If these two light control films 21 and 22 are laminated in this direction, a haze value of 60% or more is exhibited in an angle γ wider than the respective light scattering angle region β.

  The third light control film 23 has a haze of 60% or more in the range of the angle δ with the normal direction as the center. That is, the bisector of the light scattering angle region δ is in the normal direction. Then, the third light control film 23 is further laminated on the laminated body composed of the two light control films 21 and 22 so that the directions of the light scattering angle regions β and γ are parallel to each other. Thus, the light control film laminate of the present invention is constituted.

  At this time, when the light scattering angle region of the first light control film 21 and the light scattering angle region β of the second light control film 22 overlap each other by 5 ° or more, the obtained light control film When the laminate is applied to a projection screen, a brighter image can be obtained in front of the screen, which is advantageous. On the other hand, if the angle at which the two light scattering angle regions overlap is too large, the viewing angle expansion effect will be sacrificed, so depending on the extent of the light scattering angle region in the light control film before overlapping, It is preferable that there are a total of 40 ° or more, more preferably 50 ° or more, regions where the light scattering angle regions do not overlap when two sheets are stacked.

  Further, when the light scattering angle region of the first light control film 21 and the light scattering angle region of the second light control film 22 are symmetric with respect to the normal direction, the obtained light control film stack is obtained. When applied to a projection screen, the visual characteristics are the same on the right and left sides or the upper and lower sides of the screen, which is advantageous.

  In addition, in FIG. 5, although the case where the 3rd light control film 23 was laminated | stacked on the 1st light control film 21 and the 2nd light control film 22 was demonstrated to the example, those lamination | stacking orders are arbitrary. Yes, for example, a third light control film 23 may be laminated under the first light control film 21 and the second light control film 22, or the first light control film 21 and the second light control film A third light control film 23 may be inserted between the films 22. In addition, in FIG. 5, the two light control films 21 and 22 are of the same type and have the same light scattering angle range. However, different types of light scattering angle ranges are used. May be.

  Furthermore, although the case where three light control films are stacked is described as an example in FIG. 5, four or more light control films can be stacked. For example, when four or more light control films are stacked in a state where three light control films 21, 22, and 23 are stacked as shown in FIG. 5, the fourth or Subsequent light control films may be laminated such that the direction of the light scattering angle region thereof is substantially the same as the direction of the light scattering angle region of the light control films 21, 22, 23, for example, or substantially orthogonal. You may laminate | stack so that it may. In this case, the stacking order can be arbitrarily selected. Further, the fourth or later light control film also has a light scattering angle region showing a haze of 60% or more, more than 30 °, particularly 40 ° or more, like the three light control films 21, 22, and 23. Further, it is more preferably 45 ° or more.

  By adopting the multi-layer structure as described above, the light control film laminate of the present invention has the optical axis incident from the image display unit when applied to a projection screen, the viewer side (that is, the screen). It is possible to widen the maximum incident angle that can be bent in a direction perpendicular to the vertical direction. As a result, the viewer can see that the entire screen appears bright and uniform, that is, the high sensitivity area is greatly expanded. Bring.

  The projection screen can be formed as a laminate in which the light control film laminate is attached to the surface of a transparent substrate such as transparent glass or transparent plastic, or is interposed between a plurality of substrates. . In addition, light diffusion by using the above light control film laminate on a polished glass or a light diffusing plate with a relatively small amount of filler added and reduced light diffusibility to increase total light transmittance. It can also be used as a projection screen having excellent properties and high total light transmittance. The substrate used when forming the light control film can be used as the transparent or light diffusing substrate as it is.

  The light control film laminate may be used as a flat plate in which a plurality of light control films are laminated, or the outermost layer may have a lenticular lens shape. As a method of forming a lens curved surface, there is a method of forming a light control film having a lens curved surface in addition to a method of laminating the above light control film laminate on a substrate having a lens curved surface. When the latter method is employed, for example, a mold having a lens curved surface is used, and a photocurable resin composition is applied thereto and further irradiated with light to give the cured product a lens curved surface.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further more concretely, this invention is not limited by these examples. In the examples, the part representing the content or amount used is based on weight.

Reference example 1
Tribromophenoxyethyl acrylate (refractive index 1) with respect to 50 parts of polyether urethane acrylate (refractive index 1.481) obtained by the reaction of polypropylene glycol having an average molecular weight of about 2,000, toluene diisocyanate and 2-hydroxyethyl acrylate. .567) A photocurable resin composition to which 50 parts and 3 parts of benzyldimethyl ketal were added was applied on a glass plate to a thickness of about 220 μm. An 80 W / cm rod-shaped high-pressure mercury lamp is placed at a position 120 cm above the coating, and an interference filter that selectively transmits ultraviolet light with a wavelength of 313 nm is installed on the irradiation surface, and light is perpendicular to the entire coating. The light control film (1) is obtained by moving the glass plate with the coating film laterally at a speed of 0.7 m / min through a light-shielding plate with slits so as to hit (see FIG. 3). It was. The light scattering angle region showing a haze value of 60% or more was in the range of 67 to 113 ° (region of 46 ° width).

Reference example 2
The light control film (2) was operated in the same manner as in Reference Example 1 except that the light of the high-pressure mercury lamp on the resin composition coating film was irradiated at an angle of 15 ° from the normal direction of the coating film. Got. The light scattering angle region showing a haze value of 60% or more was in the range of 80 to 130 ° (region of 50 ° width).

Reference example 3
Using two light control films (2) prepared in Reference Example 2, one sheet is left attached to the glass plate, and another sheet is peeled off from the glass plate on the light control film side (the side opposite to the glass plate). In such a state, the light control film was laminated so that the light scattering angle regions were opposite to each other with the normal direction as the center to obtain a two-layer light control film laminate (3).

Example 1
On the light control film laminate (3) having a two-layer structure prepared in Reference Example 3, the light control film (1) prepared in Reference Example 1 is peeled off from the glass plate and has the same light scattering angle range. The light control film laminate (4) having a three-layer structure was obtained by laminating in the direction. The light control film laminate (4) attached to the glass plate was used as a screen. At this time, the light scattering angle region was arranged in a horizontal (horizontal) direction.

Comparative Example 1
The light control film (2) produced in Reference Example 2 was formed on a glass plate, so that the direction of the light scattering angle region was the horizontal (horizontal) direction to obtain a screen.

Comparative Example 2
The light control film laminate (3) having a two-layer structure produced in Reference Example 3 is formed on a glass plate, and its light scattering angle region is set in the horizontal (horizontal) direction so that the screen It was.

Evaluation Method and Evaluation Results With respect to the screens of Example 1 and Comparative Examples 1 and 2, a goniophotometer (GP-230 manufactured by Murakami Color Research Laboratory Co., Ltd.) was used, and the incident angle on the screen was 40 to 40. The light scattering intensity was measured in the range of 140 ° and the exit angle from the screen of 30 to 150 °. Next, an image is projected from a projector installed 50 cm behind (back side) of the center of the screen having a width of 1 m, and 0 m, 0.2 m, 0.4 m, and 1.m from the center to the right 1 m forward (front side) of the screen. Based on the above measurement results, the intensity of light emitted toward the observer from each point in the horizontal direction on the screen was calculated on the assumption that there was an observer at each point 0 m away. Each horizontal point on the screen is plotted on the horizontal axis, and the intensity of light emitted from that point toward the observer is plotted on the vertical axis. The graph is shown in FIG. Also, from the shape of this graph, the uniformity of the image was evaluated according to the following criteria and shown in Table 1.

<Judgment criteria for image uniformity>
○: Good.
Δ: Although not uniform, the image can be identified.
X: It is quite non-uniform and the image is difficult to identify.

  As shown in FIG. 6, in the screen of Example 4, the plot of each graph is relatively flat and the shapes of the graphs are similar, that is, the brightness of the screen even when the observer is at various points. Is almost uniform. On the other hand, the screens of Comparative Example 1 and Comparative Example 2 have large irregularities in the plots of the respective graphs, and the shapes of the graphs are not similar. Is different.

It is a longitudinal section showing an example of a projection display roughly. It is a figure for demonstrating the measuring method of the angle dependence of a haze. It is the side view (A) and perspective view (B) which show the example of the apparatus in the case of irradiating light from a perpendicular direction with respect to a photocurable resin composition coating film. It is the side view (A) and perspective view (B) which show the example of the apparatus in the case of irradiating light from the diagonal direction with respect to a photocurable resin composition coating film. It is a longitudinal cross-sectional view which illustrates typically the example in the case of laminating | stacking three light control films and obtaining the light control film laminated body of this invention. The horizontal axis represents each point on the screen used in the evaluation of Example 1 and Comparative Examples 1 and 2, and the vertical axis represents the intensity of light emitted from that point toward the observer. It is a graph.

Explanation of symbols

1 …… Projection display,
3 …… Light source unit,
4 …… Image display unit,
5. Projection lens
6 …… Mirror,
7 …… Screen,
8: Test piece for measuring haze value,
10 …… Conveyor,
12 …… Shading plate,
13... Slit provided on the light shielding plate,
15 …… A rod-shaped light source lamp,
20... A substrate on which a photocurable resin composition film is formed,
21, 22, 23: Light control film.

Claims (5)

Light control film whose haze value is angle-dependent and has a light scattering angle region of 30 ° or more showing a haze value of 60% or more when light is incident on the surface at an angle of 0 to 180 ° A light control film laminate formed by laminating three or more layers,
Two of the light control films have a light scattering angle region that is biased with respect to the normal direction, the light scattering angle regions are substantially parallel to each other, and the light scattering angle region is centered on the normal direction. Laminated so that the light scattering angle region overlaps each other so as to be in the opposite direction,
Furthermore, another sheet is laminated so that the center of the light scattering angle region substantially coincides with the normal direction, and the direction of the light scattering angle region is substantially parallel to the previous two light control films. A light control film laminate characterized by comprising:   2. The light control film laminate according to claim 1, wherein the light control film is obtained by irradiating and curing a composition containing at least two kinds of photopolymerizable monomers or oligomers having different refractive indexes. .   3. The light control film stack according to claim 1, wherein the two light control films whose light scattering angle regions are biased with respect to the normal direction overlap each other by 5 ° or more. body.   4. The light control film according to claim 1, wherein the two light control films in which the light scattering angle region is biased with respect to the normal direction have a light scattering angle region that is symmetrical with respect to the normal direction. Light control film laminate. A projection screen comprising the light control film laminate according to claim 1.

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