JPH10246917A - Lenticular screen - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the picture quality and to easily and accurately provide a screen with a light absorbing layer enhancing the picture quality by arranging a diffusion layer on the emitting light side of an incident lens layer and specifying the type of a diffusion material used for the diffusion layer and the thickness of the diffusion layer. SOLUTION: On the emitting light surface side of the lens layer 1 provided with plural lenses projecting toward the emitting light surface side and made of transparent resin, the diffusion layer which is obtained by distributing the diffusion material 2 satisfying conditions being an expression I; 0.01<=|Nd-Nm|<=0.2 and an expression II; 1μm<=Dd<=20μm in the transparent resin by density being >=4wt.% and <=20wt.% and whose thickness is 20μm-500μm is laminated. Besides, the light absorbing layer 3 pattern-formed by obliquely making light for exposure on a blacked photosensitive resin layer laminated on the layer 4 and hardening it by exposure is formed. In the expressions, Nd shows the refractive index of the material 2, Nm shown the refractive index of the transparent resin of the layer 4 and Dd shows the average grain size of the material 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lenticular screen for projection televisions and other video equipment.

[0002]

2. Description of the Related Art In recent years, various types of displays have been developed and commercialized as large displays. Among them, projection television is promising. In particular, transmission-type projection televisions can be made thinner,
In recent years, it has been rapidly spreading because it can be applied without using a darkened room while being able to apply liquid crystal and liquid crystal technology.

[0003] However, projection televisions have problems of luminance, image resolution, viewing angle, and color unevenness. The cause is a lenticular screen for forming an image and widening the viewing angle horizontally and vertically.

The following are known as conventional lenticular screens.

(1) As shown in FIG. 1, a lens layer 1
A light-absorbing layer 3 provided in a portion through which image light does not pass while dispersing material 2 is dispersed throughout
436). This light absorbing layer 3 is generally called a black stripe, and as an effect, it enhances the contrast of the screen by absorbing external light without reflecting it, and shields stray light that is not collected by the incident light side lens. It is an object.

(2) As shown in FIG. 2, a transparent layer provided with a diffusion layer 4 in which a diffusion material 2 for forming an image and widening a viewing angle is dispersed, and a light absorption layer 3 similar to the above. A combination of the lens layer 1 and a separate sheet material.

(3) As shown in FIG. 3, a transparent lens layer 1 and a diffusion layer 3 in which a diffusion material 2 is dispersed are laminated and integrated, and a light absorption layer 3 is provided on the diffusion layer 4. (Japanese Patent Laid-Open No. 5
-61120).

(4) A transparent lens layer which is patterned with a photosensitive resin, then dyed black to form a light absorbing layer, and then forms a diffusion layer by applying a lacquer (Japanese Patent Publication No. 53-53). No. 31017).

[0009]

In the case of the lenticular screen (1), the incident image light is partially diffusely reflected by the diffusing material 2 while passing through the lens layer 1, and generates stray light. Poor image brightness, resolution, and sharpness. The lenticular screen of the above (2) is one in which this disadvantage is improved, but the diffusion layer 4 containing the diffusion material 2 is used.
The lenticular screen of the above (3) is a further improvement in this drawback, since the above-mentioned sheet is separately required, and the number of parts increases, which makes it difficult to handle.

The lenticular screens (1) to (3) are commonly provided with a convex portion on the exit light surface side in order to easily provide the light absorbing layer 3 at a predetermined position on the exit light surface side. 5 is formed, and the light absorbing layer 3 is provided thereon. However, since the surface of the lenticular screen has an uneven shape, the appearance is poor, and as shown in FIG. 4, the projections 5 hide the image surface when actually viewed from the emission light surface side. However, there is a problem that the viewing angle becomes narrow. In addition, in recent years, in order to improve the resolution of an image, the pitch of the lens of the lenticular screen has been required to be reduced, and the difficulty in providing such a convex portion 5 with high accuracy in position and shape has increased. ing. For this reason, a method of printing the light absorbing layer 3 by screen printing has been considered, but it is difficult to align the light absorbing layer 3 with the pitch of the lens on the incident light surface side.
, And the brightness is reduced.

Therefore, it is conceivable to form a light absorbing layer using a photosensitive resin as described in (4) above.

In the above (4), in order to accurately expose and cure by light irradiated from the incident light surface side and to perform patterning, the exposure and curing of the photosensitive resin is performed at the stage of a transparent lens layer having no diffusion layer. Then, after patterning and dyeing black to form a predetermined light absorbing layer, a diffusion layer is further formed by applying lacquer.

However, the diffusion layer formed by applying a lacquer has a problem that the diffusivity is non-uniform and easily peeled off. Also, in order to expose and cure a predetermined area, not only does the angle of the parallel light for exposure have to be greatly changed by 40 ° or more, but the photosensitive resin layer that has been exposed and cured and patterned must be dyed black. However, there is a problem that the process is complicated, the workability is poor, and the machine is large. Furthermore, the accuracy of the region to be exposed and hardened greatly depends on the accuracy of the lenticular lens, and if the lens shape is not formed with high accuracy over the entire surface, the light absorbing layer can be accurately formed over the entire surface. Can not. That is,
As shown in FIG. 5, even if the light 7 for exposure is focused on the surface of the lens layer 1 on the side of the emission light, if the curvature of the lens is large, the focus shifts to the position shown in FIG. When the curvature is small, the focus is shifted to a position as shown in FIG. In each case, the cured region of the photosensitive resin is thicker than that in FIG. 5 and the position is shifted, so that the emitted light of the image overlaps the light absorbing layer, the transmittance is low, and the viewing angle is narrow. 5 to 7, 1 is a lens layer,
Reference numeral 6 denotes a photosensitive resin layer, and reference numeral 7 denotes light for exposure.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and provides a viewing angle, brightness of transmitted light, and sharpness of an image which have not been obtained so far. It is an object of the present invention to be able to easily and accurately provide a light-absorbing layer for further improving sharpness.

[0015]

According to the present invention, in order to achieve the above object, a diffusion layer is provided on an outgoing light side of an incident lens layer, and a type of a diffusion material used for the diffusion layer and a thickness of the diffusion layer are carefully selected. Thus, the image is improved, and the light absorbing layer for further improving the image can be easily and accurately provided.

That is, according to the present invention, the transparent resin satisfies the following formulas (I) and (II) on the outgoing light surface side of a transparent resin lens layer having a plurality of lenses protruding toward the incident light surface side. A diffusion layer having a thickness of 20 to 500 μm in which a diffusion material is dispersed at a concentration of 4 wt% or more and 20 wt% or less is laminated, and the blackened photosensitive resin layer laminated on the diffusion layer is exposed from the incident light surface side. A lenticular screen comprising a light absorbing layer which is formed by patterning by exposing and curing light by obliquely entering light for use.

0.01 ≦ | Nd−Nm | ≦ 0.2 (I) (Nd indicates the refractive index of the diffusion material, and Nm indicates the refractive index of the transparent resin of the diffusion layer.) 1 μm ≦ Dd ≦ 20 μm ( II) (Dd indicates the average particle size of the diffusing material.)

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below in more detail.

As shown in FIG. 8, the lenticular screen according to the present invention comprises a transparent resin lens layer 1 having a plurality of lenses protruding toward the incident light surface, and a diffusing material formed on the transparent resin. The light-exposure light 7 is incident on the blackened photosensitive resin layer laminated on the diffusion layer 4 from the incident light surface side, and is cured by exposure. It has a light absorbing layer 3 formed.

As the transparent resin in the present invention, for example, acrylic resin, polycarbonate, polyvinyl chloride, polyester and the like can be mentioned. Among them, acrylic resin having high transmittance and good light resistance is preferable. Among these acrylic resins, an impact-resistant acrylic resin is particularly preferable in order to compensate for a decrease in strength of the screen due to the shape of the lenticular lens. The impact-resistant acrylic resin is described in JP-A-53-58584 and JP-A-55-94.
As disclosed in JP-A-917 and JP-A-61-32346, it is manufactured by a multi-stage sequential polymerization method in which an elastic layer and an inelastic layer are alternately formed around a core material of an acrylic polymer. It is a multi-stage polymer.

The above transparent resin is used for both the lens layer 1 and the diffusion layer 4.
The transparent resin used for the diffusion layer 4 may be the same or different. These thermoplastic resins may be colorless and transparent, but may be, for example, colored and transparent colored light black to sink the black of the image. In particular, in order to improve the resolution of an image, it is preferable that the light absorption spectrum contains a material having a selected wavelength characteristic at a visible wavelength.

The difference between the refractive index of the diffusing material 2 used in the present invention and the refractive index of the transparent resin of the diffusing layer 4 depends on the light diffusing property and the image forming property, that is, the performance of the lenticular screen and the obtained light absorption. It is largely related to the width and accuracy of the layer 3 and even the resolution. From this, in the present invention, the diffusing material 2
And the refractive index Nm of the transparent resin of the diffusion layer 4 need to satisfy the following formula (I).

0.01 ≦ | Nd−Nm | ≦ 0.2 (I) The absolute value of the difference between the refractive index Nm of the transparent resin of the diffusion layer 4 and the refractive index Nd of the diffusion material 2 is zero or very small. In this case, since light is not refracted at the interface between the transparent resin and the diffusion material 2, the unevenness of the surface only affects the light diffusivity, and the light diffusivity is small. On the other hand, when there is a difference in the refractive index between the transparent resin of the diffusion layer 4 and the diffusion material 2 as in the present invention, the light is refracted at the interface between the transparent resin and the diffusion material 2, so that the light diffusivity increases. . The absolute value of the difference between the refractive index of the transparent resin and the diffusion material 2 is
As shown by the above formula (I), it is necessary to be 0.01 to 0.2. When the absolute value of the difference between the refractive indexes is smaller than 0.01, light is hardly refracted at the interface between the transparent resin and the diffusion material 2, and a necessary diffusion effect cannot be obtained. As a result, when the light absorbing layer 3 is provided using a photosensitive resin, the light for exposure 7 is not diffused by the diffusion layer 4 and the line width of the light absorbing layer 3 becomes too thin. Conversely, if the absolute value of the difference in refractive index is larger than 0.2, the total reflection increases, and a phenomenon called stray light occurs, in which light is scattered inside the screen or on the light source side, and as a result, light is blocked. , The transmittance is reduced. As a result, when the light absorption layer 3 is provided using a photosensitive resin, the diffusion of the exposure light by the diffusion layer 4 becomes too large, and the light absorption layer 3 is formed even in a portion where image light passes. Become. In order to effectively utilize the refraction of light at the interface between the transparent resin and the diffusion material 2, reduce the influence of stray light, and expose the photosensitive resin from the lens surface to provide the light absorbing layer 3 with a more optimal line width. The absolute value of the difference between the refractive indices of the transparent resin and the diffusing material 2 is preferably 0.01 to 0.1, and more preferably 0.02 to 0.07.

The average particle size of the diffusing material 2 used in the present invention has a correlation with the absolute value of the difference in refractive index of the diffusing material 2 with respect to the transparent resin. It is preferable to use fine particles having a small particle size, and fine particles having a large particle size for the diffusing material 2 having a small absolute value of the difference in refractive index. The average particle size Dd of the diffusion material 2 used needs to be in the range of the following formula (II).

1 μm ≦ Dd ≦ 20 μm (II) When the average particle diameter Dd is smaller than 1 μm, the light source is transparent even if the light diffusing property is high, and when the average particle diameter is larger than 20 μm, the light diffusing property is affected by the surface condition. Would. Preferably 3 to 1
0 μm.

The diffusing material 2 has an absolute value of the difference in refractive index of the diffusing layer 4 with respect to the transparent resin in the range of 0.01 to 0.2, and if it has transparency, for example, glass beads, silicone-based crosslinked beads And organic fine particles. Its shape is, for example, sphere, ellipse, cuboid, triangular pyramid,
Any of a scale shape and the like can be used. But,
The preferred diffusing material 2 has a good surface condition, high transparency, is easily controlled to a sphere (true sphere) shape capable of diffusing light in a uniform direction, and can easily adjust the refractive index difference. It is a styrene-acrylic crosslinked polymer fine particle. The styrene-acrylic crosslinked polymer fine particles are spherical fine particles obtained by polymerizing a styrene monomer, methyl methacrylate, and a crosslinking agent by a suspension polymerization method or the like. As a crosslinking agent,
For example, polyfunctional monomers such as ethylene glycol dimethacrylate, divinylbenzene, 1,6-hexanediol, trimethylpropane trimethacrylate, and trimethylpropane triacrylate can be used.
At the time of this polymerization, the refractive index is 1.49-by changing the polymerization ratio of the styrene monomer and methyl methacrylate.
Fine particles in the range of 1.59 can be adjusted and synthesized.

The diffusing material 2 used in the present invention may be colorless and transparent like the transparent resin used in the present invention, or may be colored and transparent colored, for example, light black to improve contrast. Further, in order to improve the resolution of the image, it is preferable that the light absorption spectrum contains a material having a selected wavelength characteristic at a visible wavelength.

It is necessary that the diffusion material 2 in the diffusion layer 4 is not less than 4 wt% and not more than 20 wt%. The higher the concentration, the better the image formation and the light diffusibility are. If the amount is less than 4 wt%, a good image light imaging state cannot be obtained. When the content is more than 20 wt%, the light transmittance is reduced and the line width of the obtained light absorbing layer 2 is too large. Further, since it is difficult to disperse a large amount of the diffusing material 2 in the transparent resin, it is preferable that the amount
t% or less, and more preferably 5 wt% or more and 15 wt% or less.

The thickness of the diffusion layer 4 depends on the diffusion material 2 in the diffusion layer 4.
Has a correlation with the concentration of
It needs to be 500 μm. When the thickness is less than 20 μm, it is difficult to form image light, and when the thickness is more than 500 μm,
The light transmittance is reduced, the generation of stray light in the diffusion layer 4 is increased, and the line width of the obtained light absorption layer 3 is too large.
The thickness is preferably 50 to 250 μm, and particularly preferably 50 to 150 μm in consideration of the image forming properties.

Regarding the shape of the lens in the present invention,
A shape in which circular convex lenses are arranged vertically and horizontally, and a shape in which a convex lens having a semi-cylindrical shape are arranged horizontally are preferable. The semicircular shape may be a semicircle or an arc having a constant radius, or may be a vertically long or horizontally long elliptical shape. Further, the curved portion may have a shape formed by a plurality of polynomial equations. Preferably, it is a semicircular or circular arc-shaped lens which is easy to form a base mold.

The pitch of the lens and the curvature thereof are 0.03-1.0 mm, and the curvature is 0.05-1.0 mm.
It is preferably 1.5 mm. The line width of the light absorbing layer 3 is related to the pitch and the curvature of the lens.
0.5 mm is preferred. If the thickness of the light absorbing layer 3 is too large, the light is obstructed when the screen is viewed obliquely, and if it is too thin, stray light in the image light is transmitted.
It is preferably about 0.1 mm.

It is preferable that the focal point of the light emitted from the lens has a focal point in the diffusion layer 4 of the present invention. Diffusion layer 4
By being focused inside, an image is formed in the diffusion layer 4, and the image formed by the diffusion layer 4 can be projected with a wide viewing angle. Further, the focal point may be provided in the diffusion layer 4, and the deviation of the focal point within the thickness range of the diffusion layer 4 can be tolerated as unevenness of the lens shape. If the focal point is within the diffusion layer 4, an image can be formed, so that the image can be viewed without uneven brightness or color.

When the photosensitive resin layer is cured by irradiating light from the lens surface on the exit light side, the light 7 for exposure is diffused by the diffusion layer 4 due to the presence of the diffusion layer 4.
It is not necessary to greatly change the angle of irradiation. Also,
Even if the focal point shifts within the diffusion layer 4, the light absorption layer 3 having substantially the same line width can be provided under the influence of the diffusion layer 4 within the diffusion layer 4, so that the error in the lens shape is caused by the fact that the focal point is diffused. Since it is within the allowable range even if the thickness of the layer 4 is shifted, it is advantageous from the viewpoint of production.

Regarding the shape of the diffusion layer 4 on the emission light surface side, there is no need to provide any irregularities except for the irregularities before and after the size of the diffusing material 2 (irregularities due to the diffusing material 2).
Basically, it may have a horizontal plane shape. As shown in FIGS. 1 to 3, it is possible to provide a lens shape on the outgoing light surface side. However, since the phase is shifted from the lens shape on the incident light surface side and the front luminance is easily reduced, A horizontal plane shape is preferred.

As the photosensitive resin used for the light absorbing layer 3 in the present invention, a known resin is used. For example, a prepolymer and, if necessary, an ethylenically unsaturated monomer, a photopolymerization sensitizer,
A composition comprising a thermal polymerization inhibitor can be used.

Examples of the prepolymer include unsaturated polyesters having an ethylene copolymerizable unsaturated group, unsaturated polyurethanes having an ethylene copolymerizable unsaturated group, diazo compounds having an ethylene copolymerizability, and unsaturated polyurethane polyacrylates. , Unsaturated epoxy acrylate,
Isophorone diisocyanate, acrylate having a cyanuric ring, a mixture of a polyisocyanate compound and an isocyanuric acid derivative, and the like are used. The photopolymerization sensitizer may be a known one, and for example, benzophenone alkyl ethers, benzophenone, 2,2-dimethoxy-phenylacetophenone and the like are used. Examples of the thermal polymerization inhibitor include, for example, hydroquinone, tert-butylhydroquinone, benzoquinone, 2,6-di-tert-P-
Cresol and the like are preferred.

To improve the adhesion between the photosensitive resin layer and the diffusion layer 4, an undercoat layer can be interposed.
This undercoat layer can be provided as a resin layer having a hydrophilic group such as a hydrophilic acrylic resin or a hydrophilic ethylene resin, an acrylic resin layer to which silica oxide is added, or a vapor deposition or sputtering layer of silica oxide.

As a light source of the exposure light 7 for curing the photosensitive resin layer, for example, a mercury lamp, an arc lamp, a xenon lamp, an ultraviolet fluorescent lamp or the like can be used. Exposure light 7
Is preferably in the ultraviolet region, particularly 400 nm or less. More preferably, the region is 380 nm or less. The exposure light 7 is preferably parallel light. If it is a wide-angle light beam, it is difficult for light passing through the lens to condense, and the light absorbing layer 3
It is difficult to cure only necessary parts. As a method of making parallel light, a method of making parallel light with a polarizing filter so as to be parallel to the arrangement of lenses, and a method of making parallel light with a slit are known.

Exposure light for curing the photosensitive resin layer is applied obliquely to the incident light surface of the lens layer 1 as shown in FIG. By irradiating the light obliquely, as shown in FIG. 8, the light absorbing layer 3 can be provided in a portion where the image light is not emitted. As a method of irradiating obliquely, a method of inclining a light source and a polarizing filter or a slit,
There are a method of inclining the slit and the polarizing filter obliquely with respect to the thickness direction, a method of inclining the irradiation sample obliquely, and the like.

The photosensitive resin layer formed on the diffusion layer 4 is
It is previously blackened. The blackening can be performed by dispersing a black powder in the photosensitive resin or adding a black dye to the photosensitive resin, or both of them can be used. In particular, when a black powder is dispersed, the surface of the cured photosensitive resin becomes uneven due to the influence of the black powder, and the surface reflection is reduced. Therefore, it is preferable to use the dispersion of the black powder or the addition of a black dye in combination.

As the black powder to be dispersed in the photosensitive resin, for example, carbon, copper oxide, metal sulfide and the like are used, and among them, carbon is preferable. The particle size of the carbon used is preferably 0.05 to 50 μm. Although it depends on handling and the size of the light absorbing layer 3, particularly preferable is 0.1 mm.
1 to 30 μm. The concentration of black powder is 3-60 wt%
Is preferred. If the amount is less than 3 wt%, the light absorbing function at the time of curing is insufficient, and if it is more than 60 wt%, light is difficult to transmit, and the photosensitive resin is hard to cure. More preferably, it is 5 to 30% by weight.

As the black dye to be added to the photosensitive resin, an organic black dye such as a diazo dye may be used,
Black may be obtained by using a plurality of colored dyes and mixing them. Further, a dye which is blackened by a thermal reaction such as a leuco dye or a pressure reaction, or a dye which is blackened by a thermal reaction such as an imino compound and an isocyanate compound may be used.

After the light-absorbing layer 3 is provided, the light-absorbing layer 3 may be peeled off by scratching or the like, or the lenticular sheet may be easily damaged, so that the light-emitting side of the lenticular sheet and / or An overcoat layer may be provided on the incident light surface side. As the overcoat layer, a silicon-based or fluorine-based resin is preferable. In particular, for a fluorine-based resin having a refractive index of 1.3 to 1.4, it is preferable to coat the overcoat layer with a thickness of 550/4 nm because an antireflection effect can be imparted.

It is also preferable to provide the lenticular sheet of the present invention with an antireflection property. After overcoating with a silicon-based resin, it is preferable to overcoat with a low-refractive fluorine-based resin having a refractive index of 1.3 to 1.4, because this antireflection effect can be obtained.

As a method for imparting the lens shape of the lens layer 1, for example, a method in which a flat transparent resin plate is sandwiched between molds having the lens shape and hot pressed to shape the shape, or a method in which the lens shape is similarly applied. A method is conceivable in which a molten transparent resin is poured into a molded mold, cooled, and then removed from the mold. In particular, a method in which a transparent resin is extruded by extrusion molding and sandwiched between rolls provided with a lens shape to form a sheet shape while imparting a lens shape is preferable since the number of working steps is small.

As a method of laminating the lens layer 1 and the diffusion layer 4 in the present invention, lamination using an adhesive, lamination via an adhesive layer, heat welding, vibration welding, coextrusion, and the like are preferable. Particularly preferred is co-extrusion, which has few working steps, has little disturbance of the lamination interface, and has no possibility of delamination during secondary processing.

For coextrusion, two ordinary extruders are used. For extruding the lens layer 1, 40 mmφ, 60 mmφ, 90 mmφ
For extruding the diffusion layer 4 such as an extruder having a diameter of mmφ, a smaller extruder having a diameter of 20 mm, 30 mmφ, or 45 mmφ is used. As a raw material used for the diffusion layer 4, a material in which the diffusion material 2 is dispersed in a transparent resin in advance using a blender, a turn blur, or the like, and then pelletized by an extruder is used.

The thickness of the lenticular screen of the present invention is related to the lens shape based on the viewing angle and is not particularly limited. However, if it is too thick, there is a problem in that it is lightweight, which is also an advantage of a projection television. Therefore, 0.1 to 5 mm is preferable.

[0049]

The present invention will be described below in detail with reference to examples and comparative examples. The evaluation and test methods used in each of the examples and comparative examples are as follows.

(A) Evaluation of Refractive Index: Measured by using sodium D line using “Abe type refractometer type 3” manufactured by Atago.

(B) Evaluation of 1/3 viewing angle: Evaluation was performed using a three-dimensional goniophotometer “GP-III” manufactured by Optec. FIG. 9 shows a schematic diagram of a three-dimensional goniometer. The photomultiplier 10 is placed on the optical axis, that is, at a position where the light transmittance is maximized, so that the light source 8 is irradiated to the sheet surface side of the sample 9 vertically. Sample 9 is
The lens side is installed facing the light source. The light intensity at this time is V (mV). The photomultiplier 10 is rotated around the center of the sheet surface of the sample 9 as an axis, and the light intensity becomes 1 /
A 1/3 viewing angle of 3 V (mV) is measured.

(C) Evaluation of light transmittance: JIS K-71
"1001-DP type" manufactured by Nippon Denshoku Industries Co., Ltd.
Using a haze meter, the sample is placed with its lens surface facing the light source, and the total light transmittance is measured.

(D) Measurement of phase difference: The phase difference between one cycle of the lens and the pitch of the light absorbing layer is measured. Evaluation points are 3
A part of the lenticular screen having a width of 0 cm was sampled, and as shown in FIG. 10, the absolute value t of the difference between the position of the most convex portion of the lens on the incident light surface side and the center position of the light absorbing layer 3 was determined. Regarding the absolute value of the difference from the half value of one cycle of the lens, the cross section of the sample is observed using an IC inspection microscope “OPTIPHOT 88” manufactured by Nikon Corporation, and a photograph is taken at 235 × to measure the phase difference. In FIG. 10, 1 is a lens layer and 4 is a diffusion layer.

(E) Evaluation of impact resistance: JIS K-5
Based on 400, a 50% breaking energy is measured using a DuPont impact tester manufactured by Toyo Seiki Seisaku-sho, Ltd. The shooting type and cradle use 1/4 inch. By pulling out the pin from a predetermined height, the weight is dropped to impact the shooting mold. Also, place the sample so that the lens surface comes to the cradle. The test is performed by applying an impact from the tip of the shooting mold using 100 g of the weight. At this time, when the sample is broken, the height is lowered by 2.5 cm, and when the sample is not broken, the test is raised by 2.5 cm. A continuous 20 in which the number of times of breaking and the number of times of not breaking each become 10 times in this way
Choose the test point for the test. The average height at that time is determined from the average value. From this average height and the weight of 100g used,
Find the 50% breaking energy.

(F) Evaluation of Adhesion Strength of Light Absorbing Layer: A cellophane tape is stuck on the light absorbing layer of the lenticular screen thus prepared, rubbed lightly, and then vigorously peeled off.
At this time, when the light absorbing layer was peeled off, the evaluation was x, and when the light absorbing layer was not peeled off, or when the light absorbing layer was slightly peeled off, the evaluation was o.

(G) Evaluation of Image The prepared lenticular screen is placed in front of the Fresnel lens and the lenticular screen mounted on the main body of the projection television (Matsushita Electric Industrial Co., Ltd., 48 inch wide). The lenticular screen is mounted with a lenticular lens attached vertically and the lenticular screen created so that the lenticular lens faces vertically to the lenticular lens. When the image is viewed, the image is evaluated as "O" when the image is clearly visible, and as "X" when the image is dark or blurred.

Examples 1 to 6 Sheets were prepared by laminating the lens layers and the diffusion layers shown in Table 1.
The method of preparing the laminated sheet is the combination shown in Table 1, using an extruder having a diameter of 20 mm and L / D = 32 for the diffusion layer, and using an extruder having a diameter of 40 mm and L / D = 32 for the lens layer. Extruded. The temperature of the polishing roll is
Both the middle and lower rolls were extruded at 70 ° C. and the die was extruded at a feed block type of two types and two layers, the lip opening was 3.0 mm, and the extruder temperature was 265 ° C. The thickness of the laminated sheet was adjusted to a target of 2.0 mm by the clearance of a polishing roll, and the thickness of the second layer was adjusted by the extrusion amount of an extruder. In addition, about the provision of a lens shape, the roll which shaped the lens shape for transferring a lens shape to the polishing roll which a lens layer side touches first was used. That is, as shown in FIG. 11, the upper, middle, and lower rolls 11, 1
A sheet having a width of 30 cm was prepared while taking the middle roll 12 out of the rolls 2 and 13 as a roll having a lens shape. The finished lenticular lens had a curvature of 0.75 mm and a lens pitch of 0.55 mm.
In FIG. 11, the materials and adjustments used for the diffusion layer and the lens layer 14 are a die and the lens 15 is a sheet on which a lens is shaped are as follows.

Preparation of diffusing material (styrene-acrylic crosslinked polymer fine particles): The polymerization ratio of styrene monomer and methyl methacrylate was set to 2: 8, and 5 wt% of ethylene glycol dimethacrylate was added as a crosslinking agent. Then, particles having a refractive index of 1.51 measured by the method (A) were obtained. The particles are dispersed in an aqueous surfactant solution by ultrasonic waves, and the particles are automatically centrifuged by an automatic particle size distribution analyzer (Horiba Seisakusho's “C
APA-700 type "), the particle size distribution was measured by a light transmission type sedimentation particle size distribution measuring method. Further, the particles were classified so as to have an average particle size of 5 μm by a method combining the sedimentation classification method using the difference in the sedimentation speed of the particles and the centrifugal classification method using the centrifugal force. ) Got.

Particles having a refractive index of 1.53 as measured by the method (A) were obtained by using a polymerization ratio of styrene monomer and methyl methacrylate of 4: 6, and using the same ethylene glycol dimethacrylate as a crosslinking agent as described above. Was. Then, the particles were classified in the same manner as above to obtain diffusion materials (b) and (c) having average particle diameters of 20 μm and 5 μm.

Further, at the time of the above polymerization, 50 ppm of a black coloring agent “Sumiplast G2” manufactured by Sumitomo Chemical Co., Ltd. is added as a coloring agent, and polymerization is performed. The refractive index is measured in the same manner as described above, and the particles are classified. With a refractive index of 1.53 and an average particle size of 5
A μm diffusion material (d) was obtained. Here, this diffusion material (d)
Is colored, so it is difficult to read with an Abbe refractometer. Therefore, for the styrene-acrylic crosslinked polymer fine particles, the refractive index is determined by the ratio of the styrene monomer to methyl methacrylate, so that the pyrolysis was measured by pyrolysis gas chromatography, and the polymerization ratio of the styrene monomer to methyl methacrylate was also measured. . The measurement results confirmed that the diffusing material (d) had a refractive index of 1.53 because the ratio of the styrene monomer to methyl methacrylate was 4: 6 of the polymerization ratio.

Adjustment of transparent resin: As shown in Table 1, acrylic resin and impact acrylic resin were used as the transparent resin. As an impact-resistant acrylic resin, in a continuous phase consisting of a copolymer of methyl methacrylate and methyl acrylate,
Using an acrylic resin in which an acrylic ester elastomer containing butyl acrylate as a main component was dispersed and measured by the method (A), the refractive index of the impact-resistant acrylic resin was 1.49. Further, regarding the coloring, "Blast Red 835" of an anthraquinone-based organic dye manufactured by Arimoto Chemical Co., Ltd., "Sumiplast Yellow HLR" of an azo-based organic dye manufactured by Sumitomo Chemical Co., Ltd., and "Sumiplast Green" of an anthraquinone-based organic dye were used. G "was added in the amount shown in Table 1 and colored black. Fine particles are blended with these transparent resins at the concentrations shown in Table 1 and homogeneously mixed using a tumbler or Henschel mixer, and then melt-kneaded at a resin temperature of 250 ° C. in a vented extruder 30 mmφ to pelletize and adjust the raw materials. did.

Preparation of Diffusion Layer Raw Materials: As shown in Table 1, a transparent resin and a diffusing material were blended at the concentrations shown in Table 1, and mixed homogeneously using a tumbler or Henschel mixer. Resin temperature 250
The mixture was melt-kneaded at a temperature of 0 ° C. and pelletized to prepare a raw material for a diffusion layer.

Preparation of Light Absorbing Layer (Table 2): A sheet in which a diffusion layer and a lens layer are laminated is fixed to a spin coater rotating plate, and while being rotated at 100 rpm, a negative mold made by Asahi Kasei Kogyo Co., Ltd. Table 2 in Photosensitive resin "FP-50"
The photosensitive resin blackened using carbon powder having an average particle diameter of 1 μm was dropped at a viscosity of 130 cps. After spreading the liquid over the entire surface, the number of revolutions was increased to 2500 rpm.
, And then dried in an electric oven at about 45 ° C. for about 10 minutes. Next, as shown in FIG. 12, using a plate-making ultraviolet exposure device 16 adjusted to parallel light using a slit and a polarizing plate, the lens surface of the laminated sheet is moved by P degrees (78 degrees) with respect to the lens surface. Degree) Exposure was performed for 3 minutes while swinging around ± 6 degrees about the tilted angle. Thereafter, the film was developed with an alkali developer for 5 minutes, washed with water, and dried to produce a relenticular screen shown in Table 2. In FIG. 12, 17 is a blackened photosensitive resin layer,
1 is a lens layer and 4 is a diffusion layer.

Formation of Overcoat Layer of Fluorine Resin:
In Examples 4 and 5, after the above operation, the fluororesin (“CYTOP” manufactured by Asahi Glass Co., Ltd.) was dipped in a solution dissolved in alcohol, pulled up, and air-dried to form a fluororesin thin film (overcoat layer). Was provided on both sides of the lenticular screen.

COMPARATIVE EXAMPLE 1 As shown in FIG. 1, a diffusing material 2 is dispersed throughout the sheet, and a lens protruding on the incident light surface side and a light absorbing member on the outgoing light surface side of the lens layer 1 having a lens also on the outgoing light surface side. A lenticular screen having the layer 3 and further having the projections 5 was formed.
Acrylic resin ("Delpet 70H" manufactured by Asahi Kasei Corporation)
Is mixed and dispersed at a concentration of 1 wt% with the diffusing material (c).
After homogenous mixing using a tumbler, vented extruder 3
The raw material melt-kneaded at 0 mmφ at a resin temperature of 250 ° C. and pelletized was extruded using an extruder having a diameter of 40 mm and L / D = 32. The temperature of the polishing roll is set to 70 ° C for the upper, middle and lower rolls,
Seed 2 layer feed block type, lip opening is 3.0mm
And the extruder temperature was 265 ° C. The thickness of the laminated sheet is 2.0 mm with the clearance of the polishing roll.
Adjusted to the goal. The lens shape was applied by using a roll having a lens shape and a lens shape for transferring a convex portion provided with a light absorbing layer to a polishing roll to which the resin first touches. That is, the upper, middle, and lower rolls 11 in FIG.
A sheet was prepared while taking out the shape of the convex portion, on which the light absorbing layer was provided on the upper roll 11, using the roll provided with the lens shape on the middle roll 12. The light-absorbing layer was provided on the top surface of the protruding portion by bringing a flat plate coated with a black paint mainly composed of carbon and acrylic into contact with the protruding portion on which the light-absorbing layer of the sheet thus formed was provided.

Comparative Example 2 A sheet in which a diffusing material was dispersed throughout the sheet as shown in FIG. 1 and a lens was projected on the incident light surface side was prepared. Extrusion molding was performed using the same raw materials and extrusion conditions as in Comparative Example 1. As the polishing roll, a lens shape was given to the middle roll 12 in FIG. As for the light absorbing layer, a light absorbing layer was provided by the method performed in Examples 1 to 5.

The lenticular screens of Examples 1 to 5 and Comparative Examples 1 and 2 were evaluated in (B) to (G). Table 3 shows the results. In Comparative Example 2, since there was no light diffusing agent for forming an image, an image was evaluated by installing a diffusion plate whose surface was uneven by sandblasting in front of the lenticular screen.

Examples 1 to 5 all had a wide 1/3 viewing angle and a high total light transmittance, and were preferred as a lenticular screen. Using a blackened photosensitive resin and exposing from the lens surface and using the diffusion layers of Examples 1 to 5, lenticular screens with almost no phase difference were produced. The line width of the light absorbing layer was 0.29 mm, and the light absorbing layer could be formed with a length necessary to cut unnecessary image light transmitted without cutting necessary image light. Further, in each of Examples 1 to 5, even when the image was actually mounted on a projection television and the image was evaluated, the image was bright and the edges of the image were clearly seen. In particular, in the case of Example 5, the phenomenon in which the diffusion material appeared white disappeared, and the image became darker, and the contrast of the image became clear.

In Examples 1, 2, 3 and 5, the impact resistance was high because the impact resistant acrylic resin was used as the transparent resin. In Examples 4 and 5, since the overcoat layer of the fluorine-based resin was provided on both surfaces in a thin film, the lenticular screen having high durability in which the light absorbing layer was hard to peel off was obtained.

In Comparative Example 1, since the diffusing material was dispersed over the entire surface, light loss due to stray light was large, and as a result, the total light transmittance was low. In addition, since the 1/3 viewing angle is narrow and a phase difference occurs between the lens and the light absorbing layer, transmitted light cannot be transmitted through the light absorbing layer, which is not preferable as a lenticular screen. Also, since the light absorbing layer is provided with a convex shape at the time of molding,
The phase difference between the lens and the light diffusion layer was shifted, which was not preferable.

In Comparative Example 2, since the diffusion layer was not provided, the 1/3 viewing angle was narrow, which was not preferable. The light absorbing layer had no phase difference, but had no diffusion layer, so the line width was 0.15 mm, and the light absorbing layer could not be set to the required length. Therefore, when the image was evaluated using the diffusion plate, the image appeared to be displaced because the light passed through to the extra light that would have been blocked by the light absorbing layer in addition to the formed image.

[0072]

[Table 1]

[0073]

[Table 2]

[0074]

[Table 3]

[0075]

According to the present invention, it is possible to obtain a viewing angle, a brightness of transmitted light, and a sharpness of an image which could not be obtained so far, and further improve the brightness of the transmitted light and the sharpness of the image. A lenticular screen provided with an absorption layer easily and accurately can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic view of a conventional lenticular screen.

FIG. 2 is a schematic view of another conventional lenticular screen.

FIG. 3 is a schematic view of another conventional lenticular screen.

FIG. 4 is a view showing the shielding of a viewing angle when a convex portion for a light absorbing layer is provided.

FIG. 5 is a view showing an exposure state when a curvature of a lens shape is correct in a conventional lenticular screen.

FIG. 6 is a view showing an exposure state when the curvature of a lens shape is reduced in a conventional lenticular screen.

FIG. 7 is a view showing an exposure state when the curvature of a lens shape is increased in a conventional lenticular screen.

FIG. 8 is a schematic view of a lenticular screen of the present invention.

FIG. 9 is a conceptual diagram of a method of measuring a 視野 viewing angle.

FIG. 10 is a conceptual diagram of a method for measuring a phase difference.

FIG. 11 is a conceptual diagram of a method for producing a lenticular screen in an example.

FIG. 12 is a conceptual diagram of a method for forming a light absorbing layer in an example.

[Description of Signs] 1 lens layer 2 diffusing material 3 light absorbing layer 4 diffusing layer 5 convex portion 6 photosensitive resin layer 7 exposure light 8 light source 9 sample 10 photomultiplier 11 upper roll 12 middle roll 13 lower roll 14 die 15 lens Formed sheet 16 UV exposure unit for plate making 17 Blackened photosensitive resin layer

Claims (5)

[Claims] 1. On the outgoing light surface side of a transparent resin lens layer having a plurality of lenses protruding toward the incident light surface side, a diffusing material that satisfies the conditions of the following formulas (I) and (II) is added to the transparent resin.
Thickness 20 to 20% by weight or less and dispersed at a concentration of 20 to 20% by weight or less.
A light absorption layer in which a diffusion layer of 500 μm is laminated, and exposure light is obliquely incident on the blackened photosensitive resin layer laminated on the diffusion layer from the side of the incident light from the side of the incident light and cured by exposure. A lenticular screen comprising: 0.01 ≦ | Nd−Nm | ≦ 0.2 (I) (Nd indicates the refractive index of the diffusion material, and Nm indicates the refractive index of the transparent resin of the diffusion layer.) 1 μm ≦ Dd ≦ 20 μm (II) ( Dd indicates the average particle size of the diffusion material.) 2. The lenticular screen according to claim 1, wherein at least one of the transparent resin forming the lens layer and the transparent resin forming the diffusion layer is an acrylic resin. 3. The lenticular screen according to claim 1, wherein the diffusing material is styrene-acrylic crosslinked polymer fine particles. 4. The lenticular screen according to claim 1, wherein the lens layer and the diffusion layer are laminated by co-extrusion molding. 5. A lenticular according to claim 1, wherein an overcoat layer of a silicon-based resin and / or a fluorine-based resin is provided on the outgoing light surface side and / or the incident light surface side. screen.