JP3308140B2 - Lenticular sheet for 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 lenticular sheet constituting a transmissive screen used in a liquid crystal projection television in combination with a Fresnel lens sheet, and more particularly to a simple structure having a lens portion formed on only one side. The present invention relates to a lenticular sheet which is capable of making a fine pitch (miniaturization) of a lens portion in which convex cylindrical lenses (semi-cylindrical convex lenses) are juxtaposed and which is easy to manufacture.

[0002]

2. Description of the Related Art A transmissive screen generally comprises a combination of a Fresnel lens sheet and a lenticular sheet. As shown in FIG. 3, the lenticular sheet has a convex cylindrical lens surface formed on both surfaces, and has a single surface (for image light). In general, a projection is formed at the boundary between the cylindrical lenses on the emission side, and a light-shielding layer (light-absorbing black stripe) is formed above the projection.

A convex cylindrical lens surface is formed on the front and back of a CRT having a three-tube projector (light source).
This is because in the case of the system, it is necessary to correct the deviation of the three colors by the lens on the incident side.

In recent years, liquid crystal projection televisions have become widespread, and a transmission screen for observing the image has been demanded. Since the number of pixels of a liquid crystal projector has been increased along with higher definition of image quality, a fine pitch of a cylindrical lens is also required for a lenticular sheet. Specifically, the current 0.7m
A fine pitch of about 0.3 mm or less from around m is required.

[0005] The lenticular sheet is currently obtained by press-molding a transparent thermoplastic resin sheet or by performing double-side molding simultaneously with melt extrusion. According to the method, it is very difficult to make the above fine pitch. The reason for this is that the temperature is non-uniform at the time of cooling after thermoforming, and the molded product is warped or the heat shrinkage is non-uniform.

As a manufacturing method suitable for molding a fine pitch lens sheet, ultraviolet (or electron beam)
Various molding methods using a curable resin are known, and the proposals exemplified below are representative.

[0007] An ultraviolet curable resin is injected into a gap between a Fresnel mold and a transparent resin plate, and is irradiated with ultraviolet rays to polymerize and bond the transparent resin plate to the transparent resin plate. And a UV curable resin having a Fresnel lens surface on the anti-transparent resin plate side (and a method for producing the same).

[0008] After applying an ultraviolet (electron beam) curable resin to a Fresnel mold, the resin is laminated while defoaming a film.
After molding by irradiation with ultraviolet rays (electron beams), the film (and resin) is released, and then integrated with the transparent substrate.

Ultraviolet light (electron beam) represented by the above proposal
Most of the molding methods using a curable resin are aimed at manufacturing a Fresnel lens sheet having a complicated shape as compared with a lenticular, and no proposal has been made regarding the production of a lenticular sheet for a transmission screen. Is the current situation.

[0010]

SUMMARY OF THE INVENTION The present invention has a fine-pitch lens portion suitable for observation of a high-definition and high-quality liquid crystal projection television, and a fine-pitch light-shielding pattern corresponding to the lens portion. It is an object of the present invention to provide a lenticular sheet which is easy to manufacture while having a precise structure formed.

According to a first aspect of the present invention, in a lenticular sheet constituting a transmission screen in combination with a Fresnel lens sheet, convex cylindrical lenses are juxtaposed on one side of a transparent support at intervals of 0.3 mm or less. lens section made is, is formed by a cured product of a radiation curable resin, the other surface and which planar surface of the support, through a UV-sensitive resin layer having adhesiveness before UV exposure, the A stripe-shaped light-shielding pattern is formed by transfer at a position on the surface of the ultraviolet-sensitive resin layer, which corresponds to a boundary portion excluding a non-adhesive portion based on the condensing action of each cylindrical lens, and the light-shielding is performed. The diffusion layer is formed on the pattern .

According to a second aspect of the present invention, there is provided the lenticular sheet for a transmission screen according to the first aspect, wherein a film having an antistatic function is laminated on the diffusion layer.

According to a third aspect of the present invention, there is provided the lenticular sheet for a transmission screen according to the first aspect, wherein a film having an antireflection function is laminated on the diffusion layer.

[0014]

By using an ultraviolet (electron beam) curable resin, it is possible to make a fine pitch which cannot be realized with a molded article made of a thermoplastic resin, and to produce a fine pitch lenticular sheet having a minimum pitch of 50 μm. Can be.

In the existing lenticular sheet,
In order to widen the viewing angle at the time of observation, SiO ₂ , Al ₂ O
_{3. A} diffusion film in which an inorganic powder such as CaCO ₃ is mixed into a lenticular sheet, or a diffusion film in which the above powder is kneaded, or a diffusion film in which the above powder is mixed with a binder to form a coating material is applied to the surface of the lenticular sheet. And so on. In any case, the light-shielding pattern (black stripe) is formed on the diffusion layer and has a problem that it is exposed to the outside and is easily damaged. According to the configuration of the present invention, the fine pitch light-shielding pattern is protected by the diffusion layer, and it is possible to prevent the light-shielding pattern from being damaged.

A structure in which a film having an antistatic function or an antireflection function is laminated on the diffusion layer.
According to 3), each function is exhibited when the lenticular sheet is used, and the function of protecting the diffusion layer is fulfilled.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the drawings. (A) Manufacturing apparatus: see FIG. 2 FIG. 2 shows a continuous manufacturing apparatus for lenticular sheets.
The manufacturing apparatus includes an application device (2) for applying an ultraviolet curable resin to a support film (1) supplied from a roll;
A lens forming roll (3) having a reverse shape of a lenticular lens formed on the surface, a pressing roll (3 '), an ultraviolet irradiation device (4), and a support film on which the lenticular lens is formed, on the side opposite to the lens. A pair of laminating rolls (5, 5 ') for laminating an ultraviolet-sensitive resin film (6) supplied from a roll, an ultraviolet irradiator (9), and a transfer paper (11) supplied from the roll to a black transfer layer Roll pair (10, 10 ') for forming a film, a pair of laminating rolls (13, 13') for laminating a diffusion film (14) supplied from a roll, an antistatic function or reflection supplied from a roll Roll pair (1) for laminating a transparent resin film (16)
5, 15 ') and the like.

(B) Manufacturing method A lenticular sheet is manufactured by the following process using the above manufacturing apparatus. As the support film (1), a transparent resin film having ultraviolet transmittance is preferable, and it is more preferable that the side on which the lens portion is to be formed is subjected to an easy-adhesion treatment of an ultraviolet-curable resin. As the material, polyethylene terephthalate (PET), polycarbonate (PC), polyvinyl chloride (PVC), or the like is used.

The UV curable resin coating device (2) is not particularly limited, but is preferably a coating device such as a doctor blade or a die coat. Support film (1)
The thickness of the UV curable resin applied to one side of the surface varies depending on the shape of the lenticular lens to be formed.
０．２0.2 mm is appropriate. Note that the coating thickness can be adjusted by the viscosity of the resin, the feed speed of the support film, and the like.

Next, the support film coated with the ultraviolet curable resin is passed between a pair of lenticular molding rolls (3, 3 '), and the shape of the lens molding roll (3) is changed to the ultraviolet curable resin. Simultaneously with the transfer, the resin is cured by ultraviolet irradiation from an ultraviolet irradiation device (4).
A lens forming roll (3) having an inverted shape of a lenticular lens formed on the surface is provided by disposing a cut metal mold or a resin mold duplicated from the metal mold by a predetermined method on the roll surface. Can be obtained.

Next, a support film on which a lenticular lens made of an ultraviolet curable resin is formed is supplied to a pair of laminating rolls (5, 5 '), and is supplied from the roll to the opposite side of the support film from the lens. The ultraviolet-sensitive resin film (6) is laminated.

A method of forming a light-shielding pattern at a position corresponding to a boundary between fine-pitch cylindrical lenses is proposed in Japanese Patent Application No. 7-210723 filed by the present applicant. The above proposal utilizes the difference in the presence or absence of adhesiveness between the exposed part and the non-exposed part of the photosensitive resin, and by exposing from the lens part side, the adhesive part of the photosensitive resin layer formed on the back surface Is subjected to a light-shielding process.

Also in the present invention, a light-shielding pattern is formed on a flat surface of a lenticular sheet utilizing the principle proposed above. As the UV-sensitive resin film (6),
It is preferable that the UV-exposed part becomes non-tacky by the reaction, and the unexposed part shows the property of being tacky. As the above-mentioned UV-sensitive resin film, for example, a chromin film (trade name; manufactured by DuPont) is used, and is passed through a pair of laminating rolls (5, 5 ′) heated to 110 ° C., and the opposite side of the support film to the lens Laminate to Then
By irradiating ultraviolet rays from the ultraviolet irradiator (9), a light-collecting portion based on the light-collecting action of the lenticular lens
After forming a non-adhesive portion / adhesive portion corresponding to the non-light-collecting portion on the ultraviolet-sensitive resin film and peeling off the protective film on the surface from the film (not shown), a pair of laminating rolls (10, 10 ') Then, the black transfer layer is transferred only from the transfer paper (11) supplied from the roll to the adhesive portion to form a light shielding pattern. For pressure transfer of the light-shielding pattern, for example, a chrominance ink foil (trade name; manufactured by DuPont) is used, and the line width of the light-shielding pattern (black stripe) is adjusted by the amount of exposure to ultraviolet light and the film feeding speed. Can be. In addition, instead of laminating the ultraviolet-sensitive resin film, a liquid ultraviolet-sensitive resin may be applied and formed, and instead of transferring the black transfer layer, a black powder toner may be adhered only to the adhesive portion. The shading pattern may be formed without departing from the gist of the present invention.

Next, a diffusion film (14) supplied from a roll is laminated on the entire surface including the light-shielding pattern by a pair of laminating rolls (13, 13 '). As the diffusion film (14), for example, YS300 (trade name; manufactured by Somar Industries Co., Ltd.) or the like is used. The diffusion film (14) can be laminated at room temperature by performing an adhesive process on a side to be laminated on the lenticular sheet.

Finally, a transparent resin film (16) provided with an antistatic function or an antireflection function according to the purpose.
Is passed through a pair of laminating rolls (15, 15 ') to be laminated. As the transparent resin film (16) having an antistatic function, a method of kneading a nonionic, anionic or cationic surfactant into a film, or a method in which the above surfactant is mixed with a binder and applied to the film surface Method,
A method of forming a conductive film by vacuum-depositing a conductivity-imparting substance (for example, indium oxide doped with tin oxide) on a film surface can be used. Examples of the transparent resin film (16) having an antireflection function include SiO ₂ ,
It can be obtained by mixing an inorganic powder such as Al ₂ O ₃ or CaCO ₃ with a binder to form a coating, applying the coating on the film surface, and laminating a non-glare film having a roughened surface. As described above, the lenticular sheet having the configuration shown in the cross-sectional explanatory view of FIG. 1 is manufactured.

[0026]

As described above, the lenticular has a fine-pitch lens portion suitable for observation of a high-definition and high-quality liquid crystal projection television, and has a precise configuration in which a fine-pitch light-shielding pattern corresponding to the lens portion is formed. A sheet is provided, and a lenticular sheet having a fine pitch of 0.3 mm or less required for a transmission screen for a liquid crystal projection television can be easily produced.

[0027]

[Brief description of the drawings]

FIG. 1 is an explanatory sectional view showing a lenticular sheet of the present invention.

FIG. 2 is an explanatory view showing a continuous manufacturing apparatus for lenticular sheets.

FIG. 3 is an explanatory sectional view showing a conventional lenticular sheet.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 21 ... Lens part 22 ... Transparent support 23 ... Light shielding pattern 24 ... Diffusion layer 25 ... Transparent resin film 30 ... Lenticular sheet

Claims (3)

(57) [Claims] 1. A lenticular sheet constituting a transmission screen in combination with a Fresnel lens sheet, wherein a convex cylindrical lens is formed on one side of a transparent support.
The lens portions arranged side by side at intervals of not more than mm are formed of a cured product of a radiation-curable resin, and the flat surface that is the other surface of the support is exposed to ultraviolet light.
Via UV-sensitive resin layer having adhesiveness to, the purple
Of each cylindrical lens on the surface of the external photosensitive resin layer
A lenticular sheet for a transmission screen having a configuration in which a stripe-shaped light-shielding pattern is formed by transfer at a position corresponding to a boundary portion excluding a non-adhesive portion based on a light-condensing action, and a diffusion layer is formed on the light-shielding pattern. . 2. The lenticular sheet for a transmission screen according to claim 1, wherein a film having an antistatic function is laminated on the diffusion layer. 3. The lenticular sheet according to claim 1, wherein a film having an anti-reflection function is laminated on the diffusion layer.