JPH10301208A - Lenticular sheet for transmission type screen - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a lenticular sheet for a transmission type screen adequate for observation of a liquid crystal projection television having high fineness and high image quality by forming a diffusion layer, light shielding layers in the positions corresponding to the boundary parts of the boundary parts of respective cylindrical lenses and further a diffusion layer in this order on a transparent base. SOLUTION: A diffusion film subjected to tacky adhesive processing on its plane surface is laminated on the opposite side of the lens parts 10 of the lenticular sheet to form the diffusion layer 50. Next, a photosensitive resin layer 30 is formed on the surface of this diffusion layer 50 by using a film-like photosensitive resin having non-tacky adhesives and tacky adhesive materials in correspondence to the exposure parts and non-exposure parts by UV rays. The striped light shielding layers 40 are then formed by irradiating the photosensitive resin layer 30 with the parallel beams of the UV rays from the lens side of the lenticular lenses and using Indian ink transfer foil in the tacky adhesive parts of the photosensitive resin layer corresponding to the unexposed parts at the boundary of the lenses in accordance with the condensing effect of the lenses. The diffusion layer 50 laminated with the diffusion film subjected to tacky adhesive processing is formed on the surfaces of the light shielding layers.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lenticular sheet constituting a transmission screen used in a liquid crystal projection television in combination with a Fresnel lens sheet.

[0002]

2. Description of the Related Art A transmissive screen generally comprises a combination of a Fresnel lens sheet and a lenticular sheet, and the lenticular sheet has convex cylindrical lens surfaces formed on both sides, and a boundary between the cylindrical lenses on the image observation side. In general, a lenticular sheet (FIGS. 1 (a) and 1 (b)) has a configuration in which a ridge portion is formed on the portion, and a black stripe-shaped light shielding layer is formed on the ridge portion. is there.

The reason why the convex cylindrical lens surfaces are formed on the front and back sides is that in the case of a three-tube type CRT type projector, it is necessary to correct the displacement of three colors by the lens on the observation surface side.

In recent years, liquid crystal projection televisions have become widespread, and a transmission screen for observing the image has been demanded. In a liquid crystal projection television, image light color-combined by an optical system by a projector is projected onto a transmission screen via a mirror, and an observer views the projected screen through the screen.

[0005] In the case of a three-tube type CRT type projector, there was a problem of color misregistration as described above. However, in the case of a liquid crystal projection television, there is no problem of color misregistration because colors are synthesized by an optical system in the projector. It does not need to be a double-sided lenticular sheet. Therefore, the lenticular lens sheet used for the transmissive screen of the liquid crystal projection television may be a lenticular lens sheet having a lens portion having a convex cylindrical lens provided on one side, and the position of the front and back lenses is more compared to the double-sided lenticular sheet. It can be easily manufactured without any problems.

Since the number of pixels of a liquid crystal projector has increased with the increase in definition of an image screen, a finer pitch of a lens portion of a lenticular sheet having a convex cylindrical lens is required. Specifically, while the current pitch of the lens unit is about 0.7 mm, a finer pitch of 0.3 mm or less is required.

In general, a lenticular sheet is obtained by press-molding a transparent thermoplastic resin sheet or by double-sided embossing simultaneously with the melt extrusion of the thermoplastic resin. It was very difficult to miniaturize the lens with a pitch of 0.3 mm or less due to unevenness of the molded product, warpage of the molded product, and heat return phenomenon peculiar to plastic in thermoforming.

In view of the above problems, in a lenticular sheet having a lens portion in which a convex cylindrical lens is provided on one side of a transparent support, the lens portion is formed of a cured product of an ultraviolet (electron beam) curable resin, A lenticular sheet having a configuration in which a diffusion layer is provided on the flat surface of the transparent support opposite to the lens portion, and a stripe-shaped light-shielding layer is formed on the diffusion layer at a position corresponding to the boundary between the cylindrical lenses of the convex cylindrical lens ( FIG. 2) is proposed in Japanese Patent Application No. Hei.

On the other hand, in a lenticular sheet having a lens portion in which a convex cylindrical lens is provided on one side of a transparent support, the lens portion is formed of an ultraviolet (electron beam) cured product, and the transparent support opposite to the lens portion is formed. A lenticular sheet (FIG. 3) having a configuration in which a stripe-shaped light-shielding layer is provided on a flat surface of the body at a position corresponding to the boundary between the cylindrical lenses of the convex cylindrical lens, and a diffusion layer is formed thereon is disclosed in Japanese Patent Application No. Hei. -277484.

Also, with the miniaturization of the pitch of the lens portion of the lenticular sheet, the alignment when forming a stripe-shaped light shielding layer at a position corresponding to the boundary between the cylindrical lenses of the convex cylindrical lens becomes extremely difficult. It will be difficult.

As a method of forming the light-shielding layer, various printing methods such as offset, gravure, and screen are generally used. However, it is difficult to produce a printing plate with high positional accuracy and to perform positioning. Not be.

In view of the above problems, in a lenticular sheet having a lens portion in which a convex cylindrical lens is provided on one side of a transparent support, the lens of the lens portion is disposed on the flat surface of the transparent support opposite to the lens portion. A method of optically forming a light-shielding layer utilizing the action is disclosed in Japanese Patent Application No. 7-21.
0723.

The above proposal utilizes the difference in the presence or absence of adhesiveness between an exposed portion and a non-exposed portion of a photosensitive resin, and shields a portion of the photosensitive resin having an adhesiveness from light by exposure from a lens portion side. Processing is performed.

In the lenticular sheet for a transmission screen, the diffusion layer is necessary for forming an image projected from the projector. In addition, it is necessary to scatter light by a diffusing material to widen a viewing angle, and to reduce reflection of a light source for projecting a projection image, so-called hot bar, and generally, a lens portion. A diffusion layer is provided on a surface corresponding to the opposite side.

[0015] A diffusion layer is provided on the flat surface of the transparent support opposite to the lens portion proposed in Japanese Patent Application No. 8-17482, and corresponds to the boundary between the cylindrical lenses of the convex cylindrical lens. In the configuration of the lenticular sheet (FIG. 2) in which the stripe-shaped light-shielding layer is formed at the position, the viewing angle of the screen increases in proportion to the amount of the diffusion material of the diffusion layer, and the hot bar can be reduced. In the method of forming a light-shielding layer on the adhesive portion of the photosensitive resin by the exposure from the lens portion proposed in Japanese Patent Application No. 7-210723, the light of the exposure from the lens portion is used. Are scattered by the diffusion layer, the width of the stripe-shaped light-shielding layer is reduced, and the sharpness of the edge of the stripe of the light-shielding layer is reduced, so that the contrast is reduced. At the same time stripe-shaped light-shielding layer is seen to become uneven. Naturally, the viewing angle characteristics and the width of the stripe-shaped light-shielding layer were limited, and there was a disadvantage that only a lenticular sheet for a transmission screen for a limited use as a screen could be obtained.

On the other hand, a stripe-shaped light shield is provided at a position corresponding to the boundary between the cylindrical lenses of the convex cylindrical lens on the flat surface of the transparent support opposite to the lens portion proposed in Japanese Patent Application No. 7-277484. In the configuration of a lenticular sheet (FIG. 3) in which a light-shielding layer is formed on a light-shielding layer, when forming a stripe-shaped light-shielding layer, the exposure from the lens unit side proposed in Japanese Patent Application No. 7-210723 is proposed. Therefore, in the method in which the light-shielding layer is applied to the adhesive portion of the photosensitive resin, the light from the exposure from the lens portion is not scattered, so that the light-shielding light has a sharp edge and a wide stripe shape. A layer is obtained. However, the viewing angle of the screen increases in proportion to the amount of diffusion material in the diffusion layer, and the hot bar can be reduced, but the effect of the light-shielding layer that absorbs external light is reduced because the diffusion layer is formed on the light-shielding layer. As a result, there is a disadvantage that the contrast is lowered and only a lenticular sheet for a transmission screen for a limited use can be obtained as a screen.

[0017]

SUMMARY OF THE INVENTION An object of the present invention is to provide a lenticular sheet for a transmission screen which is particularly suitable for observation of a liquid crystal projection television with high definition and high image quality. More specifically, a light-shielding layer having a fine pitch is formed at a position corresponding to a boundary portion of the lens portion, and a stripe-shaped light-shielding layer having a fine pitch is formed. Lenticular sheet in which the diffusion layer made of is divided into two layers (FIGS. 4 and 5)
The object of the present invention is to provide a single-sided lenticular sheet having a lens portion on one side for a transmission type screen for high image quality and high quality with improved screen characteristics such as a viewing angle, a hot bar, and a contrast by adopting the above configuration. And

[0018]

According to a first aspect of the present invention, there is provided a lenticular sheet comprising a transmissive screen in combination with a Fresnel lens sheet, wherein a lens having a convex cylindrical lens provided on one surface of a transparent support. A light-shielding layer in the form of a stripe at a position corresponding to the boundary between the diffusion layer and each cylindrical lens on the flat surface of the transparent support opposite to the lens part, and a diffusion layer is further formed thereon in this order. A lenticular sheet for a transmission screen having the above configuration.

According to a second aspect of the present invention, there is provided a lenticular sheet for a transmission screen, wherein a lens portion provided with a convex cylindrical lens is formed of a cured product of an ultraviolet curable resin.

According to a third aspect of the present invention, there is provided a lenticular sheet for a transmission screen, wherein the diffusion layer located on the transparent support opposite to the lens portion is a kneading type diffusion layer in which a diffusion material is dispersed. is there.

According to a fourth aspect of the present invention, the diffusion layer located on the light shielding layer opposite to the lens portion is a kneading type or a surface diffusion type diffusion layer in which a diffusion material is dispersed only on the surface. It is a lenticular sheet for a screen.

<Effect> The separation between the diffusion layer located on the transparent support opposite to the lens portion and the diffusion layer located on the light-shielding layer opposite to the lens portion and the light-shielding layer results in two layers. By securing the viewing angle of the screen and dividing the amount of diffuser necessary to eliminate the hot bar into each diffusion layer, the amount of diffuser per layer can be reduced,
When the light-shielding layer is applied to the adhesive portion of the photosensitive resin by the exposure from the lens portion side, the light from the exposure from the lens portion is less scattered, and the stripe-shaped light-shielding layer has no sharp edge unevenness. Is obtained.

Also, by forming another divided diffusion layer on the stripe-shaped light-shielding layer, the contrast is improved without reducing the effect of the light-shielding layer absorbing external light.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the drawings. An ultraviolet-curable resin is applied to a mold having the reverse shape of the convex cylindrical lens, a transparent resin support such as vinyl chloride, acrylic, polycarbonate, or polyester is laminated, and ultraviolet light is irradiated from the support side to remove the ultraviolet-curable resin. At the same time as the polymerization and curing, a lens portion made of the cured product is adhered to a transparent resin support to form a convex cylindrical lens on one side, and a lenticular sheet having a flat surface of the transparent resin support on the other side. (Fig. 6 (a))

An internal diffusion type diffusion film is prepared by kneading fine particles made of an inorganic compound such as TiO 2 and SiO 2 as a diffusion material into a transparent resin film by extrusion molding or the like.

The above-mentioned diffusion film is adhesively laminated on a flat surface of the transparent support opposite to the lens portion of the lenticular sheet with a transparent film-like ultraviolet curable adhesive or tacky adhesive. (Fig. 6 (b))

Alternatively, TiO 2, Si as a diffusion material
Fine particles made of an inorganic compound such as O2 may be mixed and dispersed with a transparent binder to form a coating, and the resultant may be applied and laminated on the flat surface of the transparent support opposite to the lens portion of the lenticular sheet.

After forming a diffusion layer on one surface of the transparent support by the above-described method, an ultraviolet-curing resin is applied to a mold having an inverted shape of a convex cylindrical lens, and laminated with the diffusion surface facing upward, A lenticular sheet may be prepared by irradiating ultraviolet rays from the diffusion surface side to simultaneously polymerize and cure the ultraviolet curable resin and adhere the lens portion made of the cured product to the transparent resin support.

Next, a light-sensitive resin layer in the form of a film is formed by coating the diffusion surface which is adhered and laminated on the flat surface of the transparent support of the lenticular sheet. (Fig. 6 (c))

By utilizing the difference in the presence or absence of adhesiveness between the exposed portion and the non-exposed portion of the photosensitive resin, the exposed portion of the photosensitive resin layer formed on the diffusion surface is exposed to light from the lens portion side. A light-shielding process is performed using black powder toner or a transfer foil, and a stripe-shaped black light-shielding layer is formed at a position corresponding to the boundary between the convex cylindrical lenses. (Fig. 6 (d),
(e))

The photosensitive resin generally has an acroyl group in the molecule, and includes oligomers such as epoxy acrylates, urethane acrylates, polyester acrylates and polyol acrylates, as well as polymers and monofunctional / bifunctional groups. A methacrylic monomer having a polyfunctional group: For example, a mixture of a polymer and an oligomer such as tetrahydrofurfuryl acrylate, polyethylene glycol diacrylate, and trimethylolpropane acrylate is used.

As a diffusing material, fine particles made of an inorganic compound such as TiO2 and SiO2 are dispersed and mixed in a transparent binder, and a coating material is applied to a film of polyester or the like to form a surface diffusion type diffusion film.

The diffusion film is laminated and adhered on the light-shielding layer using a film-like ultraviolet curable adhesive, a tacky adhesive or the like with the diffusion surface facing upward. Alternatively, the above-mentioned internal diffusion type diffusion film may be bonded and laminated. Further, as a diffusing material, fine particles composed of an inorganic compound such as TiO2 and SiO2 may be dispersed and mixed in a transparent binder, and a coating material may be directly applied to the light-shielding layer to form a diffusion layer.
(Fig. 6 (f))

[0034]

EXAMPLE A stamper having a shape opposite to the shape of an aspheric lens having a lens pitch of 0.182 mm is prepared. A UV-curable resin having a thickness of 0.05 mm is applied to the stamper, and a polycarbonate transparent resin sheet (trade name: Panlite, manufactured by Teijin Chemicals) having a thickness of 0.188 mm is laminated. And a lenticular sheet having a pitch of 0.182 mm.

A kneading type diffusion film (trade name: S20T, manufactured by Kimoto) having a thickness of 0.100 mm and having been subjected to adhesive processing was laminated on the flat surface on the opposite side of the lens portion of the lenticular sheet to form a diffusion layer.

Using a film-shaped photosensitive resin (trade name: Chromalin, manufactured by DuPont) having non-adhesive and tacky properties corresponding to the exposed and unexposed areas by ultraviolet rays, A photosensitive resin layer was formed.

Irradiation of ultraviolet parallel light from the lens side of the lenticular lens is performed, and black ink transfer foil is used on the adhesive portion of the photosensitive resin layer corresponding to the unexposed portion at the boundary of the lens based on the condensing action of the lens. A striped light-shielding layer composed of a black transfer layer was formed.

Next, a surface diffusion type diffusion film (trade name: 100TL, manufactured by Kimoto) having a thickness of 0.100 mm and having been subjected to adhesive processing on the surface of the light-shielding layer was laminated to form a diffusion layer.

The above-mentioned lenticular sheet for a transmission screen was combined with a Fresnel lens sheet, mounted on a liquid crystal projection television, and the images were observed. As a result, high-quality images with high contrast and no hot bar were observed.

[0040]

According to the present invention, a lenticular sheet suitable for observation of a liquid crystal projection television having high definition and high image quality is provided. More specifically, (1) the contrast is obtained by dividing and forming the diffusion layer located on the transparent support opposite to the lens portion and the diffusion layer located on the light shielding layer opposite to the lens portion. Thus, it is possible to provide a high-quality, high-quality lenticular sheet for a transmissive screen, in which the light-shielding layer has no unevenness.

(2) By forming the lens portion with a cured product of an ultraviolet curable resin, it is possible to mold a lens with a fine pitch, which was impossible with a thermoplastic resin, and a lenticular sheet for a high-definition transmission screen. Can be provided.

[0042]

[Brief description of the drawings]

FIG. 1 is an example of a configuration of a conventional lenticular sheet for a transmission screen.

FIG. 2 is an example of a configuration of a conventional lenticular sheet for a transmission screen.

FIG. 3 is an example of a configuration of a conventional lenticular sheet for a transmission screen.

FIG. 4 is an example of a configuration of a lenticular sheet for a transmission screen of the present invention.

FIG. 5 is an example of a configuration of a lenticular sheet for a transmission screen of the present invention.

FIG. 6 illustrates an example of an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Lens of lenticular sheet 20 ... Transparent support 30 ... Photosensitive resin layer 40 ... Light shielding layer 50 ... Diffusion layer 60 ... Protective layer 70 ... Exposure of photosensitive resin Part (non-adhesive) 80: exposed part of photosensitive resin (adhesive)

Claims (4)

[Claims] 1. A lenticular sheet which constitutes a transmissive screen in combination with a Fresnel lens sheet, has a lens portion having a convex cylindrical lens provided on one side of a transparent support, and a transparent support opposite to the lens portion. A lenticular sheet for a transmission screen having a configuration in which a light-shielding layer having a stripe shape is formed on a flat surface of a body at a position corresponding to a boundary between a diffusion layer and each cylindrical lens, and a diffusion layer is further formed thereon in this order. 2. The lenticular sheet for a transmission screen according to claim 1, wherein the lens portion provided with the convex cylindrical lens is formed of a cured product of an ultraviolet curable resin. 3. The diffusion layer according to claim 1, wherein the diffusion layer located on the flat surface of the transparent support opposite to the lens portion is a kneading type diffusion layer in which a diffusion material composed of fine particles of an inorganic compound is dispersed. Lenticular sheet for transmission screen. 4. The diffusion layer located on the light-shielding layer opposite to the lens portion is a kneading type or a surface diffusion type in which a diffusion material made of fine particles of an inorganic compound is dispersed only on the surface opposite to the light-shielding layer. The lenticular sheet for a transmission screen according to claim 1.