JP2000338607A - Rear projection screen - Google Patents

Abstract

(57) [Problem] To provide a bright rear-projection screen with an excellent vertical resolution, a wide horizontal viewing angle, a wide range of images, and excellent resolution. I do. A rear projection screen including a Fresnel lens sheet and a horizontal lenticular lens sheet having a group of horizontally arranged cylindrical lenses having a function of refracting image projection light in the horizontal direction. Three optical articles each using a film-shaped vertical lenticular lens sheet having vertically arranged cylindrical lens groups having an action of refracting image projection light in the vertical direction. It is a rear projection type screen.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bright rear projection type which has a remarkably improved vertical viewing angle for use in a transmission type liquid crystal projection television, a liquid crystal display and the like, can observe images in a wide range, has excellent resolution, and has excellent resolution. Regarding the screen.

[0002]

2. Description of the Related Art A rear projection type screen used in an image projection apparatus for magnifying and projecting an image of a projection tube, a liquid crystal panel or the like, superimposing the image on a screen, and observing the image from the front is conventionally used.
As shown in FIG. 3, it has a two-lens configuration of a Fresnel lens and a horizontal lenticular lens plate in which a group of cylindrical lenses having a function of refracting image projection light in the horizontal direction are arranged side by side. The Fresnel lens plate works to direct the light emitted from the projector to the direction where the observer is,
That is, it is used to brighten the screen. on the other hand,
The horizontal lenticular plate has a function of expanding light emitted from the projector in the left-right direction where an observer is present, that is, it is used to enlarge an observation area so that many people can observe the light. Further, in order to improve the contrast, a stripe-shaped light-shielding layer is generally provided on the rear surface of the horizontal lenticular lens plate at a portion corresponding to a non-light-collecting portion of each cylindrical lens.

A conventional rear projection display composed of a Fresnel lens plate and a horizontal lenticular plate is:
Although the viewing angle is increased only in the horizontal direction, the vertical viewing angle is not considered much. The viewing angle in the vertical direction is generally increased by using a diffusing agent to increase the viewing angle in the vertical direction, thereby expanding the observation area. As another method, a vertical lenticular lens in which cylindrical lens groups are arranged in a vertical direction having an action of refracting image projection light in a vertical direction is hot-pressed on a flat surface opposite to a lens surface of a Fresnel lens plate. It was provided by molding. But,
In the method of expanding the viewing angle in the vertical direction by using the above-mentioned diffusing agent, a sufficient diffusion effect cannot be obtained. It is necessary to mix a large amount of a diffusing agent, and as a result, the loss of light amount is remarkable, and the image becomes dark, which is not practical. Further, in the conventional method in which a vertical lenticular lens for increasing the vertical viewing angle is provided on a flat surface opposite to the lens surface of a Fresnel lens plate by hot press molding, the “thermal” characteristic in plastic-specific thermoforming is used. Due to the "return phenomenon", a fine lens shape cannot be reproduced, and hence a sufficient effect cannot be obtained, and it has been difficult to expand the vertical viewing angle to a range wider than 15 degrees. Further, the hot press molding is not an economical method because the production process is complicated, and has been a factor of increasing the cost of the molded article.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has an advantage that the vertical viewing angle can be enlarged, the horizontal viewing angle is wide, and a wide range of images can be observed. It is intended to provide an excellent, bright rear projection screen.

[0005]

As a result of diligent studies, the present inventor has proposed a rear projection screen comprising a conventional Fresnel lens sheet and a horizontal lenticular lens sheet having the function of refracting image projection light in the horizontal direction. The lens shape is reproduced with extremely high precision by using a vertical lenticular lens sheet with a vertical cylindrical lens group that has the function of refracting image projection light in the vertical direction as another optical article. To be able to enlarge the vertical viewing angle, wide horizontal viewing angle, and obtain a bright, high-resolution rear-projection screen that can observe images in a wide range.
The present invention has been reached.

That is, the first aspect of the present invention provides a back surface comprising a Fresnel lens sheet and a horizontal lenticular lens sheet in which a group of cylindrical lenses arranged in a horizontal direction having a function of refracting image projection light in the horizontal direction. In the projection type screen, as another optical article, a film-shaped vertical lenticular lens sheet in which cylindrical lens groups having a function of refracting image projection light in the vertical direction are used. It is a rear projection screen characterized by being made of an optical article.

According to a second aspect of the present invention, in the rear projection screen according to the first aspect, the film-shaped vertical lenticular lens sheet is formed by forming an ultraviolet-curable resin or an electron beam-curable resin on a transparent resin film substrate. It is characterized in that a cylindrical lens group made of a cured product of a mold resin is formed.

According to a third aspect of the present invention, in the rear projection type screen according to the first or second aspect, each cylindrical lens pitch of the film-like vertical lenticular lens sheet is 100 μm or less.

According to a fourth aspect of the present invention, in the rear projection screen according to any one of the first to third aspects, a vertical viewing angle has a range of 15 degrees or more.

[0010]

An embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view showing an example of the configuration of the rear projection screen of the present invention. The Fresnel lens sheet 10, a film-like vertical lenticular lens sheet 30 in which a group of cylindrical lenses are arranged in the vertical direction having a function of refracting image projection light in the vertical direction, and the image projection light are arranged horizontally from the projection side. An optical article with a horizontal lenticular lens sheet 20 in which cylindrical lens groups are arranged in a horizontal direction having a function of refracting light in the horizontal direction is disposed, and an ultraviolet curing type is provided on a flat surface opposite to the lens surface of the horizontal lenticular lens sheet 20. A light-shielding layer 22 is provided via a resin layer 21, and the light-shielding layer 22 is provided so as to be an observation surface.

FIG. 2 is a perspective view showing another example of the configuration of the rear projection type screen of the present invention. A flat surface opposite to the lens surface of the film-shaped vertical lenticular lens sheet 30 in which the cylindrical lens groups are juxtaposed in the vertical direction having a function of refracting image projection light in the vertical direction, and a lens surface of the Fresnel lens sheet 10 And a flat surface on the side opposite to the above, with a light-transmitting adhesive layer or an adhesive layer 40 interposed therebetween, and placed on the horizontal lenticular lens sheet 20 to form a film-shaped vertical lenticular lens sheet 30.
The UV curable resin layer 2 is placed on the flat surface of the horizontal lenticular lens sheet 20 so that the lens surface of
The light-shielding layer 22 provided through the first light-receiving layer 1 is disposed so as to be an observation surface.

The vertical lenticular lens sheet in the form of a film according to the present invention is formed on a transparent resin film substrate.
It is characterized in that a group of cylindrical lenses made of a cured product of an ultraviolet curing resin or an electron beam curing resin are juxtaposed.

The above-mentioned transparent resin film substrate used in the present invention is preferably a transparent resin film having ultraviolet transmittance, and it is desirable that the surface on which the lens portion is formed is subjected to an easy adhesion treatment. Examples of the material include a polyester resin, a polycarbonate resin, and a polyvinyl chloride resin. In view of the transparency, strength and flexibility of the film, a polyester film having a thickness of 50 to 250 μm or 1
A polycarbonate film having a thickness of 00 to 700 μm is suitable, but is not particularly limited thereto.

The above-mentioned UV-curable resin or electron beam-curable resin composition used in the present invention contains a urethane (meth) acrylate and / or an epokine (meth) acrylate oligomer, a reaction diluent, etc. In the case of a mold resin, it is a composition further containing components of a photopolymerization initiator and a sensitizer.

Examples of the urethane (meth) acrylate oligomer include polyols such as ethylene glycol, 1,4 butanediol, neopentyl glycol, polycaprolactone polyol, polyester polyol, polycarbonate diol, polytetramethylene glycol, and hexamethylene diisocyanate. And organic polyisocyanates such as isophorone diisocyanate, tolylene diisocyanate, and xylene isocyanate. However, it is not particularly limited.

As the epoxy (meth) acrylate oligomer, for example, bisphenol A type epoxy resin,
It can be obtained by reacting epoxy resins such as bisphenol F type epoxy resin, phenol novolak type epoxy resin, glycidyl ether terminal of bisphenol A type propylene oxide adduct, and fluorene epoxy resin with (meth) acrylic acid. However, it is not particularly limited to these.

The film-shaped vertical lenticular lens sheet of the present invention is obtained by applying an ultraviolet or electron beam-curable resin composition to a molding surface of an embossing roll mold having an inverse shape of the lens of the film-shaped lens sheet. Supply the translucent resin film substrate to the embossing roll mold,
By irradiation of ultraviolet rays or ionizing radiation through the substrate,
At the same time as curing the resin, it can be produced by a method of polymerizing and bonding a lens made of the resin-cured molded product to a transparent substrate. Although the above manufacturing method is desirable in terms of productivity, lens molding accuracy, and the like, a cylindrical lens group made of a cured product of an ultraviolet curable resin or an electron beam curable resin is formed on a transparent resin film substrate. Is not particularly limited to the above manufacturing method.

The film pitch of the vertical lenticular lens sheet according to the present invention is not more than 100 μm. As a result, it is possible to support a high-definition screen.

On the other hand, Fresnel lens sheets and horizontal lenticular sheets are made of polystyrene resin, acrylic resin,
A method in which a sheet-like base material such as a polycarbonate resin or a vinyl chloride resin is heated and pressed in a hot melt state by a flat press using a mold. Or, in a melt extrusion molding by an extruder, it can be manufactured by a known and commonly used method such as a method of embossing a sheet-like resin base material surface extruded in a molten state using an embossing roll mold, and is not particularly limited. Absent. In addition, as described above, a lens portion having a desired shape made of a cured product of an ultraviolet ray or an electron beam curable resin can be formed on a translucent substrate.

The light-shielding layer provided on the flat surface of the horizontal lenticular lens sheet constituting the rear projection screen of the present invention utilizes the fact that an adhesive ultraviolet-curable resin is cured by irradiation with ultraviolet light to become non-adhesive. The following method for providing a light-shielding layer is preferred, but is not particularly limited. An ultraviolet curable resin layer is formed on a flat surface of the lenticular lens sheet opposite to the lens surface. Through each lenticular lens to the ultraviolet curable resin layer formed on the flat surface of the lenticular lens sheet from the lens side, irradiate vertically, and cure the resin of the portion focused by each lenticular lens After making the resin non-tacky, a light-shielding layer is formed by applying a black colorant only to the uncured portion of the adhesive resin. A black fine powder toner as a coloring agent can be selectively adhered only to the uncured portion. Alternatively, using a transfer paper provided with a black ink layer, the black ink layer can be selectively adhered only to the uncured portion. According to the above-described exposure process, the lenticular lenses are collectively irradiated with parallel light from the lens side to the entire surface of the lenticular sheet. Therefore, the formed light-shielding layer is for a non-light-collecting portion due to the irradiation of the actual lenticular sheet with ultraviolet rays, and is surely provided at a place where the light-shielding layer must be formed, that is, at a region where image light does not pass. It can be formed with high positional accuracy.

The rear projection type screen of the present invention has
It has a range of degrees or higher. In the present invention, the cylindrical lens group of the film-shaped vertical lenticular sheet, in which the cylindrical lens group having a function of refracting image projection light in the vertical direction is arranged in the vertical direction, is formed by curing an ultraviolet curable resin or an electron beam curable resin. Since it is made of an object, the lens has excellent shapeability and the vertical viewing angle can be increased.

[0022]

According to the present invention, it is possible to provide a bright rear-projection screen having an excellent vertical resolution, a wide horizontal viewing angle, a wide viewing area, and an excellent resolution. Further, according to the present invention, an inexpensive rear projection screen can be provided.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of the configuration of a rear projection screen of the present invention.

FIG. 2 is a perspective view showing another example of the configuration of the rear transmission screen of the present invention.

FIG. 3 is a perspective view showing an example of the configuration of a conventional rear projection screen.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Fresnel lens sheet 20 ... Horizontal lenticular lens sheet 21 ... UV curable resin layer 22 ... Light shielding layer (black stripe) 30 ... Film-shaped vertical lenticular lens sheet 40 ... Adhesive layer or adhesive layer

Claims (4)

[Claims] 1. A rear projection screen comprising a Fresnel lens sheet and a horizontal lenticular lens sheet having a group of cylindrical lenses arranged in a horizontal direction having a function of refracting image projection light in the horizontal direction. As one optical article, it is characterized by comprising three optical articles using a film-shaped vertical lenticular lens sheet in which a vertical cylindrical lens group having an action of refracting image projection light in the vertical direction is provided. Rear projection screen. 2. The film-shaped vertical lenticular lens sheet according to claim 1, wherein a cylindrical lens group made of a cured product of an ultraviolet curable resin or an electron beam curable resin is formed on a transparent resin film substrate. The rear projection screen according to claim 1, wherein: 3. The film-shaped vertical lenticular lens sheet has a cylindrical lens pitch of 100 μm.
3. The rear projection screen according to claim 1, wherein the distance is equal to or less than m. 4. The rear projection screen according to claim 1, wherein the vertical viewing angle has a range of 15 degrees or more.