JP3027744B2 - Transmission screen - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission screen using an ionizing radiation-curable resin, which is used for a rear projection type projector or the like.

[0002]

2. Description of the Related Art There are many transmission screens used in projection TVs and the like, in which a lenticular lens sheet and another lens sheet are combined. The lenticular lens sheet has a plurality of semi-cylindrical lenticular lens sections formed in parallel on one or both sides of a plastic sheet or film, and a band-shaped light-shielding layer is formed on the non-condensing surface on the observation side. Have been. The lenticular lens portion diffuses light from the light source, and an inorganic diffusing agent such as glass powder is added in order to further improve the diffusivity. The light-shielding layer is for increasing the contrast of the screen, and is formed by printing black ink or the like.

[0003] Such a transmission screen is manufactured by molding a lenticular lens portion on a plastic sheet by extrusion molding, press molding, or the like, or by ionizing radiation curing of an ultraviolet (UV) curable resin or the like. A so-called photopolymer method of molding a lens portion using a mold resin is known. As an example of the photopolymer method, after applying the ionizing radiation-curable resin to the base film, the lenticular lens portion is formed by passing between the mold rolls on which the lens mold is formed, and cured by irradiating ultraviolet rays or the like, A method has been proposed in which the light-shielding layer is finally formed by cutting after releasing the mold (JP-A-1-159627).

[0004]

However, in the conventional transmission screen, when an inorganic diffusing agent is added to a lenticular lens portion made of a UV-curable resin, the UV-curable resin has a monomer before curing. Alternatively, since the polymer is an oligomer and sedimentation is poor due to poor dispersibility, there is a problem that the image quality of the screen is reduced.

On the other hand, the conventional method of manufacturing a transmission screen has the following problems. In the extrusion molding method and the press molding method, a large number of dies are required, and a molding cost is required, so that the manufacturing cost is high. Further, since the processing temperature at the time of molding was high, the quality of the screen was likely to deteriorate with time. Further, since a plastic sheet is used as the substrate, when the substrate is made thinner and fine pitch (higher image quality) is intended, the mechanical strength of the entire screen is reduced. For this reason, only a material that can maintain the strength of the substrate can be selected, and as a result, it has been difficult to achieve a fine pitch.

Furthermore, since the precision of the thickness of the plastic sheet substrate is low, it is difficult to adjust the light-condensing portion of the lenticular lens portion. For this reason, when forming the lenticular lens part on the light-emitting side in the condensing part, the diffusion characteristics are apt to fluctuate, and the light-shielding layer formed in the non-condensing part cannot be widened.

The light-shielding layer is formed by forming a lenticular lens portion, cutting it into a single screen plate, and printing it in any of the above-mentioned extrusion method, press method, and photopolymer method. As described above, since the step of forming the light-shielding layer is off-line, the screen cannot be continuously produced, and the workability is poor. Furthermore, when forming the light-shielding layer, it takes time to align the printed portion, or the lenticular lens part shrinks during molding, so that the position of the lens part and the light-shielding layer may be shifted. .

An object of the present invention is to solve the above-mentioned problems,
An object of the present invention is to provide a transmissive screen which has good image quality, can realize fine pitch at low cost without deteriorating quality, and can easily form a light shielding layer to enhance workability.

[0009]

In order to solve the above-mentioned problems, a transmission type screen according to the present invention is a base film having an ionizing radiation transmitting property, and has a refraction of light from the base film on its observation side surface. A base film on which a low refractive layer having a low refractive index is formed, a first lenticular lens portion made of an ionizing radiation-curable resin formed in parallel on a light source side surface of the base film, and A light-shielding layer formed on the non-light-collecting surface of the first lenticular lens portion provided on a surface on the observation side, wherein the light-collecting surface of the first lenticular lens portion is on the observation side. The first lenticular lens portion has a pitch of less than 0.4 mm, and the light-shielding layer is formed of the base film. It is formed directly on the system.

[0010] The base film may be previously subjected to a light diffusion process for diffusing light from a light source.
Furthermore, in the first lenticular lens portion,
An insoluble organic diffusing agent may be dispersed in the ionizing radiation-curable resin.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the drawings and the like with reference to the drawings. FIG. 1 is a cross-sectional view showing a part of a prerequisite configuration of a transmission screen according to the present invention. Transmission screen 1 of this example
Has a plurality of first lenticular lens portions 12 formed in parallel on the light source side of the base film 11, and a band-shaped light shielding layer 13 formed on the non-light-collecting surface 11b on the observation side.

The base film 11 is a base material of the transmissive screen 1. The thickness of the base film 11 is such that the light-collecting surface 11 a of the first lenticular lens portion 12 is positioned substantially on the observation surface of the base film 11. I have to do it. As the base film 11, a film having good transparency of ionizing radiation such as electron beam (EB) and ultraviolet (UV) and having transparency can be used. For example, polyethylene terephthalate, nylon, polymethyl methacrylate, polychlorinated Resins such as vinyl, polycarbonate, polystyrene, and polyolefin are exemplified. A primer can be applied to the surface of the base film 11 in order to improve the adhesiveness with an ionizing radiation-curable resin or the light-shielding layer 13 described later.

The first lenticular lens section 12 focuses and diffuses light from a light source, and is formed of an ionizing radiation-curable resin. Examples of ionizing radiation-curable resins include epoxy, nylon, polyester,
Acrylic, urethane acrylate, or the like can be used, and it is desirable that the material has transparency.

The light-shielding layer 13 is provided for improving the contrast, and is formed in a band shape on the non-light-collecting surface 11b of the first lenticular lens portion 12. Light shielding layer 1
3 is formed by printing on the base film 11 using an ink or the like in which a black pigment or the like is dispersed.

In this case, the base film 11 may be subjected to light diffusion processing for diffusing light from the light source. As the light diffusion treatment, a general diffusing agent, for example, glass, silica, talc, or the like is dispersed in the base film 11, a so-called matte treatment for roughening the surface of the base film 11 is performed, or vertical diffusion is performed. Lenticular lens sheets on one or both sides.

FIG. 2 is a sectional view showing a part of one embodiment of the transmission screen according to the present invention. In this transmission screen, a low refraction layer 15 having a smaller refractive index than that of the base film 11 is formed on the surface of the base film 11 on the observation side in the transmission screen shown in FIG. The low-refractive layer 15 is formed to reduce the reflectance, and may be formed by coating the base film 11 with vinylidene fluoride, acrylic, or the like. The light diffusion treatment for diffusing light from the light source is performed on the base film 11. Specifically, a diffusing agent 11 a is kneaded into the base film 11.

The first lenticular lens section 12
In addition, as a diffusing agent, an insoluble organic diffusing agent may be dispersed in an ultraviolet (UV) curable resin. This is used because the organic diffusing agent is of the same quality as the UV-curable resin to be dispersed, and therefore has substantially the same specific gravity, has good wettability, and has good dispersibility.

As the organic diffusing agent, a styrene resin or the like can be used in addition to the crosslinked beads comprising the following (a) to (d). (A) Aromatic vinyl monomer; styrene, α-methylstyrene, vinyltoluene, halogenated styrene or the like alone or in combination thereof (b) Alkyl acrylate; methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate or the like alone or (C) alkyl methacrylate; methyl methacrylate, ethyl methacrylate, propyl methacrylate,
Butyl methacrylate or the like alone or in combination thereof (d) Crosslinkable monomer; allyl methacrylate, triallyl cyanurate, triallyl isocyanurate and the like.

Next, a method and an apparatus for manufacturing a transmission screen according to the present invention will be described with reference to the drawings. 3 and 4 are views showing an embodiment of a method and an apparatus for manufacturing a transmission screen according to the present invention,
FIG. 3 is a schematic diagram of the apparatus of the embodiment, and FIG. 4 is a process diagram of the method of the embodiment. The embodiment of the apparatus for manufacturing a transmission screen according to the present invention includes a dispenser 2, a mold roll 3, a pressing roll 4, a light source 5, a printing roll 6, a release roll 7, and the like.

The dispenser 2 is disposed obliquely above the mold roll 3 and applies an ionizing radiation-curable resin to the base film 11. The mold roll 3 is for forming the first lenticular lens portion 12 on the base film 11, and has a plurality of semi-cylindrical grooves formed in parallel on its surface. The direction of the groove (the axial direction of the lenticular lens) may be either vertical or horizontal with respect to the axial direction of the mold roll 3, but if it is the vertical direction, alignment and release are easy.

The pressing roll 4 is disposed below the dispenser 2, and is disposed between the pressing roll 4 and the mold roll 3.
Press through 1. .

The light source 5 is disposed obliquely below the mold roll 3 and, at a position where the base film 11 is wound around the mold roll 3, is irradiated with an electron beam or ultraviolet light to cure the ionizing radiation-curable resin. Let it. The printing roll 6 is disposed below the mold roll 3 and between the light source 5 and the release roll 7, and forms a light shielding layer 13 on the base film 11. In this example, the black ink filled in the ink pan 8 is applied to the base film 11, and the ink is dried by the drier 9 to form the strip-shaped light shielding layer 13.

The release roll 7 is disposed substantially opposite to the pressing roll 4, and releases the ionizing radiation-curable resin from the mold roll 3. The take-up rolls 10 apply tension to the base film 11, and are arranged one above and one below the base film 11.

Next, an embodiment of the method for manufacturing a transmission screen according to the present invention includes a coating step 101 and a forming step 1.
02, a curing step 103, a printing step 104, and a release step 105.

The application step 101 is a step of applying an ionizing radiation-curable resin to the base film 11 having ionizing radiation transparency. In the application step 101, the ionizing radiation-curable resin may be supplied to the mold roll 3 or the pressing roll 4, or may be supplied onto the base film 11. At this time, if the resin pool 12A of the ionizing radiation-curable resin is formed at the valley between the mold roll 3 and the press roll 4, the mold roll 3 and the press roll 4 can prevent air bubbles from being mixed. Can be.

In the forming step 102, the base film 11 is pressed between the mold roll 3 on which the lenticular lens mold is formed and the pressing roll 4 to form the first lenticular lens portion 12 on the base film 11. This is the step of performing The curing step 103 is a step of irradiating ionizing radiation from the light source 5 to cure the ionizing radiation-curable resin while the base film 11 is wound around the mold roll 4. As described above, the ionizing radiation-curable resin is cured while the base film 11 is in close contact with the mold roll 3, so that the moldability of the lenticular lens portion 12 is good.

The printing step 104 is a step of forming the light shielding layer 13 using the printing roll 6 when the base film 11 is wound around the die roll 3. The light-shielding layer 13 is formed on the non-light-collecting surface 11 b of the lenticular lens unit 12 on the surface of the base film 11. The light-shielding layer 13 may be printed using a gravure method, a flexographic method, a rotary screen method, or the like. Release process 105
Is a step of releasing the ionizing radiation-curable resin from the mold roll 3.

Lastly, the present invention will be described in more detail with reference to production examples and the production steps. As the base film 11, a PET film having a thickness of 100 μm was used, and an acrylic urethane-based primer was applied to the surface thereof.

The mold roll 3 has a diameter of 500 mm and a width of 50 mm.
It has a size of 0 mm, and its surface has a major axis of 0.16 mm, a minor axis of 0.11 mm, and a pitch of 0.21 m.
An elliptical lenticular lens mold of m is formed. A base film 11 of 1.6 m / m is placed between the die roll 3 and a rubber pressing roll 4 having a diameter of 100 mm.
in at the same time as the urethane acrylate-based UV-curable resin (refractive index: 1.49) is applied to the base film 1
1 (coating step 101, forming step 102).

When the base film 11 was wound around the mold roll 3, the UV curable resin was cured by irradiating 80 W / cm ultraviolet rays from the light source 5 (curing step 10).
3). Thereafter, an acrylic black ink is printed on the non-light-condensing surface 11b of the lenticular lens portion 12 by a printing roll 6 by a gravure method and dried by a drier 9 to form a light-shielding layer 1
No. 3 was formed (printing step 104).

Finally, the UV curable resin was released from the mold roll 3 by the release roll 7 (release step 105). Thus, the transmission screen 1 as shown in FIGS. 1 and 2 was obtained.

The present invention is not limited to the embodiments described above, and various modifications can be made.

The printing roll 6 is disposed between the light source 5 and the release roll 7, but is disposed between the light source 5 and the pressing roll 4 so that the light-shielding layer can be formed before or simultaneously with the curing of the UV-curable resin. 13 may be formed. The printing roll 6
It may be used also as the pressing roll 4 or the release roll 7,
The take-up roll 10 may also serve as the release roll 7.

[0034]

As described in detail above, claims 1 to 1
According to 3, since a plastic film is used for the base material, even if the transmission screen is made very thin,
Since the mechanical strength can be maintained, fine pitch (high precision) can be achieved.

In addition, since the accuracy of the thickness of the base material is high, it is easy to adjust the condensing portion of the lenticular lens portion.
The contrast can be improved by widening the light-shielding layer, and even if a lenticular lens portion is formed on the light-emitting side, the diffusion characteristics are less likely to fluctuate.

Further, if a low refractive layer is formed on the observation side of the base film, the reflection loss can be reduced. According to the first aspect, there is an effect that the wettability as a diffusing agent is good and the dispersibility is improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a part of a prerequisite configuration of a transmission screen according to the present invention.

FIG. 2 is a cross-sectional view showing a part of one embodiment of a transmission screen according to the present invention.

FIG. 3 is a schematic diagram showing an embodiment of a transmission screen manufacturing apparatus according to the present invention.

FIG. 4 is a process chart showing an embodiment of a method of manufacturing a transmission screen according to the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 transmissive screen 11 base film 12 first lenticular lens portion 13 light-shielding layer 15 low-refractive layer 2 dispenser 3 mold roll 4 press roll 5 light source 6 print roll 7 release roll 101 coating process 102 molding process 103 curing process 104 printing Process 105 Release process

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G03B 21/62

Claims (3)

(57) [Claims] 1. A base film capable of transmitting ionizing radiation.
And the light from the base film is
Base film with low refractive index layer with low refractive index
A first lenticular lens portion made of an ionizing radiation curable resin formed in parallel on a light source side surface of the base film; and a first lenticular lens provided on an observation side surface of the base film. A light-shielding layer formed on a non-light-collecting surface of the lens portion, wherein the base film has a thickness such that the light-collecting surface of the first lenticular lens portion is located on substantially the same plane as the surface on the observation side. The pitch of the first lenticular lens portion is 0.4
mm, and wherein the light-shielding layer is formed directly on the base film. 2. The transmission screen according to claim 1 , wherein the base film has been subjected to a light diffusion process for diffusing light from a light source in advance. Wherein said the first lenticular lens portion, the transmissive screen according to claim 1 or 2, characterized in that the ionizing radiation curable resin are dispersed insoluble organic diffusion agents.