JPH1090798A - Lenticular sheet exposure device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a black stripe(BS) at a similar position to all cylindrical lenses of a lenticular sheet by providing an exposure device with a cylindrical light source emitting the light of uniform intensity distribution around and a lenticular sheet holding part arranged with the light source as a center. SOLUTION: A resin layer(photopolymer) 2 which is not hardened is exposed by ionizing radiation(infrared rays) from the cylindrical lens side. The exposure device is constituted of the cylindrical infrared light source 21 and the lenticular sheet holding part arranged with the light source 21 as a center so that the lenticular sheet is bent and closely held by the cylindrical wall surface. By adjusting the irradiation range of the light from the light source 21 by a device corresponding to a diaphragm, an area where the BS is formed and the line width of the BS in the irradiation range are controlled. Then, the part of the layer 2 condensed by the lens function of the cylindrical lens is hardened and made to be non-adhesive. The part of the layer 2 which is not condensed is provided with adhesion as it is.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus used for forming a light-shielding pattern on a flat surface (non-lens portion side) of a lenticular sheet.

[0002]

2. Description of the Related Art When a lenticular sheet is applied to a transmission type projection television screen, a light-shielding pattern (black stripe; hereinafter referred to as BS) is provided at a position corresponding to a non-light-collecting portion of each cylindrical lens in order to improve contrast. ) Is conventionally performed.

As a method of forming the BS, various printing methods such as offset, gravure, screen, and the like are conventionally used. In the printing method, the positional accuracy such that the image portion becomes a light absorbing portion (BS) is used. If a lenticular sheet is made finer or a lenticular sheet is made larger, it becomes more difficult to make a printing plate and to register (position) the lenticular sheet.

[0004] A method of forming a light-shielding pattern other than a normal printing method is a method of forming a light-shielding pattern with a reliable positional accuracy on the back surface of a lens sheet without using a printing plate.
The following techniques are known.

[0005] A positive photosensitive adhesive (adhesive which loses its tackiness when exposed to light) is provided on the observation surface side of a transmission screen (lens sheet). After exposing the adhesive with light rays projected from a projection light source (projector) or a light source having an opening equivalent thereto from the surface opposite to the surface, and after removing the adhesiveness of the light-collecting portion of each unit lens of the lens sheet, The wet process is performed by spraying light-shielding toner from the observation surface, sticking it to the unexposed portion where the adhesive remains, and removing the toner that has just adhered to the portion that has become non-sticky by exposure and excess toner. A method of easily and inexpensively obtaining a transmissive projection screen in which a pattern having excellent light-shielding properties is formed without requiring it. (See Fig. 1)

It is important to provide a light-collecting unit at a position equivalent to the case where a screen is actually used, and to place a light source for exposure at the same or optically equivalent position as the projection light source. (Publication, column 8, 6-)
9th line) ", but does not disclose any specific relationship between the form of the lens sheet and the projection light source and the optical system for exposure.

FIG. 2 is an explanatory view conceptually showing a use state of the transmission type projection screen. The transmission type projection screen has a configuration in which a Fresnel lens and a lenticular sheet are combined, and projection light (similar to divergent light from a point light source) from a light source (projector) is converted into parallel light by a Fresnel lens, and the lenticular sheet is formed. With this arrangement, it functions to expand in the horizontal direction (the direction in which the cylindrical lenses are arranged) and project the image toward the observer. The BS is formed on a flat surface on the viewer side of the lenticular sheet.

That is, when assuming that “a light-collecting portion is provided on a flat surface of a lenticular sheet at a position equivalent to the case where a screen is actually used”, when a Fresnel lens is not used, the lenticular sheet is not used. The entire surface must be exposed to parallel light from the cylindrical lens side.

As shown in FIG. 3, when divergent light is applied instead of parallel light, the light is incident on the cylindrical lens at the center (front of the light source) and at the end of the lenticular sheet because the angles of incidence are different. Light position is different,
As a result, the formation position of the BS differs for each cylindrical lens. For this reason, when a lenticular sheet having a BS as described above is used as a transmission type projection screen, since a Fresnel lens is provided on the projection side, projection light impinges on the BS at the end of the screen, and a projected image to be observed is observed. However, a disadvantage that chipping occurs is caused.

In order to form a BS at the same position with respect to each cylindrical lens (the same non-light-collecting portion in all the cylindrical lenses), it is necessary to expose the entire surface with parallel light, and the transmission type projection screen has In consideration of the state of use, it is necessary to combine a Fresnel lens and provide a light source for exposure at the same or optically equivalent position as the light source (projector).

For this reason, the following proposal has been made by the present applicant. Japanese Patent Application No. 8-27682 (see FIG. 4) A lenticular sheet having a flat surface on which an ionizing radiation-curable resin layer (synonymous with the above-mentioned positive photosensitive adhesive) is formed, and a light source are arranged in the direction in which the cylindrical lenses are juxtaposed. While relatively moving, a belt-like light beam extending in the longitudinal direction of the cylindrical lens is irradiated vertically from the cylindrical lens side,
The resin layer at the converging portion is cured.

According to the above, most of the light is cut off when the light from the light source is blocked by a mask having a band-shaped slit in order to obtain “a band-shaped light beam extending in the longitudinal direction of the cylindrical lens”. As a result, a light amount is lost, and an exposure time for obtaining a required exposure amount is required.

[0013]

SUMMARY OF THE INVENTION An object of the present invention is to improve an exposure process so that a BS can be formed at the same position with respect to all the cylindrical lenses of a lenticular sheet without requiring a Fresnel lens. I do. It is a further object of the present invention to provide an exposure apparatus that can effectively use light from a light source and can shorten an exposure time for obtaining a required exposure amount.

[0014]

A lenticular sheet exposure apparatus according to the present invention comprises a lenticular sheet exposing apparatus having a cylindrical lens disposed on one side and a flat surface on the other surface of the lenticular sheet, the position corresponding to a non-light-collecting portion of each cylindrical lens. An exposure apparatus used to form a light-shielding stripe pattern, a cylindrical light source that emits a light beam having a uniform intensity distribution around the light source, and a lenticular sheet that is curved and tightly held on a cylindrical wall surface, so as to be closely held. A lenticular sheet holder disposed around a light source.

The following two types of holding parts can be considered. (1) A configuration in which a lenticular sheet is curved on the inner wall surface of the holding portion and the flat surface thereof (the side on which the positive photosensitive adhesive is disposed) is closely held. (2) a holding portion configured by curving a glass sheet or a resin sheet having transparency of a light beam to be exposed;
A configuration in which the lenticular sheet is curved so that the lens surface of the lenticular sheet and the outer wall surface of the holding section are in close contact with each other.

[0016]

FIG. 5 is an explanatory diagram showing an embodiment of the present invention. Fig. 5- (a) ... Formation of ionizing radiation-curable resin layer on flat surface of lenticular sheet An uncured state is formed on a flat surface of lenticular sheet 1 in which a cylindrical lens is arranged on one side and the other surface is a flat surface. A photopolymer (ionizing radiation curable resin) layer 2 having an adhesive property is formed, and a protective layer 3 (covering the adhesive portion of the photopolymer) is formed thereon. The lenticular sheet 1 may be a transparent thermoplastic resin such as acrylic, vinyl chloride, or carbonate molded by any method, or an ionizing radiation-curable resin such as a UV-curable resin or an EB-curable resin. It may be made of a cured product of the used resin.

In this description, the following will be used. <Lenticular sheet> A cylindrical lens group made of a cured product of a UV-curable resin (material: epoxy acrylate) is formed on a 1.0 mm thick transparent substrate (material: acrylic), and both are polymerized and adhered. Things. Pitch of cylindrical lens 0.4mm, spherical radius 0.35mm,
Lens part thickness 0.063mm, size 120cm × 90cm. <Photopolymer> Chromalin film (Dupont product name) <Protective layer> Mylar film

FIG. 5- (b) Exposure of lenticular sheet to ionizing radiation The uncured resin layer (photopolymer) 2 is exposed to ionizing radiation (ultraviolet rays) from the cylindrical lens side. The exposure device is a cylindrical ionizing radiation (ultraviolet) light source.
A lenticular sheet holding portion (not shown) is arranged around the light source 21 so as to bend and hold the lenticular sheet tightly on the cylindrical wall surface. In the figure, the light range from the light source is adjusted with the light equivalent to the "aperture".
The area where the BS is formed, the line width of the BS in the irradiation range (by adjusting the exposure time), and the like can be controlled.

<Exposure conditions> Light source used: near ultraviolet mercury lamp (output: 13 kW, 120 W /
cm)

The portion of the resin layer 2 condensed by the lens function of the cylindrical lens is cured to make the portion non-adhesive. The portion of the resin layer 2 that is not condensed by the lens function remains sticky.

FIG. 5- (c) —Step of forming BS The exposed lenticular sheet is removed from the apparatus, the protective layer 3 on the resin layer 2 is peeled off, and the resin layer 2 in a tacky state (white portion) Is colored black by a desired method. As a coloring method, a method of spraying a black toner of carbon black on the entire flat surface and removing the black toner sprayed on the non-adhesive resin layer 2 (hatched portion) may be adopted. Alternatively, the transfer ink layer (black) of the transfer sheet is overlaid on the resin layer 2 and the adhesive resin layer 2
Transfer formation of the ink layer only to (hatched portion),
A method in which the ink layer is not transferred to the non-adhesive resin layer 2 may be used. In the case of the above method, it is also effective to use the transfer sheet instead of the protective layer 3.

Next, ionizing radiation is applied to the entire surface of the resin layer 2 to completely cure the resin layer 2. (Not shown) Alternatively, a protective film may be formed by laminating a photosensitive film from above the light-shielding pattern and irradiating the film with ionizing radiation so as to prevent the formed BS from peeling off.

A protective layer having a diffusive property may be formed as the protective layer of the BS in order to diffuse the light and expand the viewing area (observation from the flat surface side of the lens sheet).
(Not shown) As an example of the protective layer having diffusivity, silicon oxide
A type in which a dispersant such as titanium oxide is mixed is exemplified.

[0024]

The effects of the present invention are listed below. (1) According to the exposure apparatus of the present invention, it does not require a Fresnel lens, and functions equally to collectively irradiating parallel light to the entire lenticular sheet from the cylindrical lens side to all the cylindrical lenses. That is, BS can be formed at the same position for each cylindrical lens. Therefore, when the lenticular sheet is combined with the Fresnel lens to be used as a transmission type projection screen, the position where the BS is formed is preferable. (2) The BS can be formed on the flat surface of the lenticular sheet without requiring a printing plate. (3) Since the BS to be formed is for the non-condensing portion due to the irradiation of the actual lenticular sheet with ionizing radiation, a pattern can be formed at a position where truly BS formation is required with reliable positional accuracy. Done. (4) The exposed light can be effectively used without any loss.

[0025]

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a method of forming a BS according to a conventional technique in the order of steps.

FIG. 2 is an explanatory view conceptually showing a use state of a transmission screen.

FIG. 3 is an explanatory view conceptually showing that a formation position of a light-shielding pattern differs depending on exposure conditions.

FIG. 4 is an explanatory view showing a method for forming a BS according to a conventional technique.

5 (a) to 5 (c) are explanatory views showing a method of forming a BS according to the present invention in the order of steps.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Lens sheet 2 ... Ionizing radiation hardening resin layer 3 ... Protective layer 11 ... Light source of ionizing radiation (ultraviolet) 12 ... Mask 13 ... Slit light 21 ... Cylindrical light source

Claims (1)

[Claims] An exposure apparatus used for forming a light-shielding stripe pattern at a position corresponding to a non-light-collecting portion of each cylindrical lens on a flat surface of another surface of a lenticular sheet having cylindrical lenses arranged on one side. There is a cylindrical light source that emits a light beam with a uniform intensity distribution around the periphery, and a lenticular sheet holding unit that is arranged around the light source so as to curve and tightly hold the lenticular sheet on the cylindrical wall surface. Lenticular sheet exposure device.