JPH0675302A - Reflection type screen for light room - Google Patents

Abstract

PURPOSE:To enjoy an image projected from a projector with high contrast even in a light room by successively forming a black base material layer, reflecting layer containing an aluminum pigment, and light diffusion layer. CONSTITUTION:This reflection type screen for light room consists of a black material layer 1, reflecting layer 2 containing an aluminum pigment, and light diffusion layer 3. As for the light diffusion layer, a plastic film having <=50 haze value can be used. As for the aluminum pigment, a flake aluminum pigment can be used. The reflecting layer 2 can be formed by alternately depositing layers containing the aluminum pigment and no pigment, and further the reflecting layer 2 may consist of plural laminated layers of transparent films printed with ink containing aluminum pigment. Thus, light with rather small incident angle to the screen can be mostly reflected as a mirror reflection in the reflecting layer 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reflection type screen used for viewing a projected image such as an OHP (overhead projector) or a liquid crystal projector, and more specifically, it can see a projected image with high contrast even in a bright room. The present invention relates to a reflective screen for a bright room.

[0002]

2. Description of the Related Art At present, OHPs have become widespread and are widely used in schools, companies, etc. When projecting an image with this OHP, a reflective screen having a white surface is usually used.

[0003]

However, in the conventional reflection type screen, when the room illumination or the external light from the window is present, the contrast ratio of the image projected on the screen is lowered and it becomes difficult to see the image. I used it with the lamp darkened, that is, the light other than the projector was blocked. Therefore, even if the observer wants to take a memo or the like while using the OHP, it is difficult for the observer to take a memo and the like, and everyone feels inconvenience. This is especially true of liquid crystal projectors in which the brightness of the light source is inferior to that of OHP.

In order to further improve the brightness of the image, there have been conventionally used a material for the reflective layer, such as white vinyl chloride or a material coated with a pearl pigment on it. However, since the screen gain is low, the room must be darkened. Could not be used. Further, there is also one using an aluminum foil or an aluminum plate as a reflection layer, but it cannot be used in a bright room because it has many specular reflection components and the screen is glaring and the contrast is insufficient.

The present invention has been made in view of the above conventional problems, and an image projected from a projector can be viewed with high contrast even in a bright room without being affected by external light or indoor lighting. It is an object of the present invention to provide a reflective screen for a bright room, which is capable of being used.

[0006]

In order to solve the above-mentioned problems, a reflection type screen for a bright room of the present invention comprises a black substrate layer,
It is formed by sequentially stacking a reflection layer containing an aluminum pigment and a light diffusion layer.

As the light diffusion layer, a plastic film having a haze value of 50 or less can be used.

A scale-like aluminum pigment can be used as the above-mentioned aluminum pigment.

The reflective layer can be formed by alternately laminating layers containing aluminum pigment and layers not containing aluminum pigment.

The reflective layer can be formed by laminating a plurality of transparent films whose surfaces are printed with an ink containing an aluminum pigment.

The structure of the present invention will be described in more detail below.

FIG. 1 is a sectional view showing the construction of an embodiment of a reflection type screen for a bright room of the present invention, which has a construction in which a reflection layer 2 and a light diffusion layer 3 are sequentially laminated on a black base material layer 1. ing.

For the black base material layer 1, for example, a vinyl chloride sheet containing carbon black can be used. The black color of the base material layer is for absorbing external light and improving the contrast of the image.

The reflective layer 2 is made of a vinyl-based or acrylic-based resin containing an aluminum pigment, and a resin coating containing the aluminum pigment is applied by an ordinary coating method or a printing method such as gravure or silk screen. It is applied to the black base material layer 1. In the present invention, it is preferable to use a scale-like aluminum pigment. The scaly aluminum pigment is easily obtained, for example, by crushing an aluminum foil. Further, a scaly pigment obtained by crushing a polyester film having a surface vapor-deposited with aluminum can also be used as the aluminum pigment of the present invention.

When the coating film is dried, the scale-like aluminum pigments 4 are distributed with directivity so that they are arranged parallel to the surface of the base material in the layer, and are distributed so as to be almost overlapped when viewed from the front direction (see FIG. 2). Further, in the present invention, it is desirable that the scaly aluminum pigment 4 is distributed with a certain interval, and it is desirable that it is distributed in a layer having a certain thickness. The content of the aluminum pigment is preferably about 0.5 to 5 parts by weight with respect to 5 to 30 parts by weight of the resin constituting the reflective layer 2. The thickness of the reflective layer 2 is preferably 20 μm or more.

Further, the reflective layer 2 does not have to have a single layer structure containing an aluminum pigment. For example, the structure may be formed by alternately laminating layers containing aluminum pigment and layers not containing aluminum pigment. It is also possible to adopt a configuration in which a plurality of transparent films whose surfaces are printed with an ink containing an aluminum pigment are laminated.

The light diffusion layer 3 is a film whose surface is embossed or matte-coated, and is made of a transparent thermoplastic resin such as oriented polypropylene (OPP), vinyl chloride, polyethylene terephthalate (PET), triacetyl cellulose (TAC). To be done. The light diffusion layer 3 also functions as a surface protective layer, and is laminated on the reflective layer 2 with an adhesive. Further, it is desirable that the haze value showing the ratio of scattered light to incident light is 50 or less.

[0018]

With such a structure, as shown in FIG. 2, when the incident light a having a relatively small incident angle on the screen, the reflected light in the reflecting layer 2 almost follows specular reflection. Therefore, since the incident angle of the light from the projector is small, almost all of the light is reflected. By the way, 100
When projecting onto an inch size screen, the distance from the screen to the entire surface of the lens is about 4.6m. In this case, the incident angle is 0 ° in front of the lens, and the incident angle at the edge of the screen is about 15 °.

On the other hand, the external light from the window and the light from the illuminating device in the room are generally incident light b having a large incident angle with respect to the screen, and thus the scale-like aluminum pigments 4 which are almost overlapped with each other when viewed from the front direction. Since the light is incident from the lateral and oblique directions, the ratio of reflection between the pigments and absorption on the surface of the black base material layer 1 increases.

As a result, the reflected light from the projector is
Even in a bright room, a bright, high-contrast projected image can be obtained without being affected by extraneous light or indoor illumination light. Further, the difference in brightness between the central portion and the peripheral portion of the screen is small, and the projected image is easy to see.

[0021]

EXAMPLES The present invention will be described in more detail below with reference to examples.

Example 1 As a layer containing an aluminum pigment, 25 parts by weight of a scaly aluminum pigment having an average particle diameter of 15 μm and a vinyl resin 1
A layer having a thickness of 20 μm was applied and formed on a vinyl chloride sheet containing glass cloth by using the silk screen printing method with 00 parts by weight of the ink. The vinyl chloride sheet used was a black one containing carbon black.

Further, a 100 μm transparent vinyl chloride sheet was laminated on the surface as a light diffusion layer and a surface protective layer with an adhesive to prepare a reflection type screen. The surface of the transparent vinyl chloride sheet was embossed with satin for diffusion of light and used with a haze value of 35.

When this screen was used for projection measurement with a liquid crystal projector HV-100 (manufactured by Sharp Corporation), a bright screen having a screen gain SG value of 4.8 and a contrast ratio of 3.5 was obtained. At this time, the brightness of the room was 100 lux, which was an environment in which a sufficient image could not be obtained on a normal screen, but the image of the screen of this example was sufficient for viewing.

The screen gain SG value and the contrast ratio are respectively

[0026]

[Equation 1] In this example, measurement was performed using a luminance meter and an illuminance meter, and these values were obtained by the above equation.

Example 2 As a layer containing an aluminum pigment, 10 parts by weight of a scaly aluminum pigment having an average particle diameter of 15 μm, an acrylic resin 1
Two kinds of inks, an ink consisting of 00 parts by weight and a transparent ink containing no pigment, are prepared. These inks are first subjected to gravure multicolor printing, and then an aluminum pigment containing layer having a thickness of 5 microns is coated with a glass cloth. A vinyl chloride sheet is coated and formed, and a transparent layer having a thickness of 5 μm is superposed on the sheet.
A total of 5 layers were formed. A black vinyl chloride sheet was used.

Further, a 100 μm transparent vinyl chloride sheet was laminated on the surface as an optical diffusion layer / surface protection layer with an adhesive to form a reflection type screen. The surface of the transparent vinyl chloride sheet was embossed with satin and had a haze value of 35.

When this screen was used for projection measurement with a liquid crystal projector in the same manner as in Example 1, the SG value was
A bright screen with a 4.8 and a contrast ratio of 3.5 was obtained. The brightness of the room at this time was 100 lux, but it was enough to see the image.

Example 3 10 parts by weight of a scale-like aluminum pigment having an average particle size of 25 microns as an ink containing an aluminum pigment, an acrylic resin
A mixture of 100 parts by weight was prepared, and three pieces of this ink were printed by gravure printing on the surface of a 25-micron-thick transparent PET film. Next, these three films were laminated on a vinyl chloride sheet containing glass cloth to form a reflective layer. A black vinyl chloride sheet was used.

Further, a 100 μm transparent vinyl chloride sheet was laminated on the surface as a light diffusion layer and surface protection layer with an adhesive to prepare a reflection type screen. The surface of the transparent vinyl chloride sheet was embossed with satin and had a haze value of 35.

When this screen was used for projection measurement with a liquid crystal projector in the same manner as in Example 1, the SG value was
A bright screen with a contrast ratio of 4.5 and 4.5 was obtained. The brightness of the room at this time was 100 lux, but it was enough to see the image.

[0033]

As described in detail above, the reflection type screen of the present invention is formed by sequentially stacking a black base material layer, a reflection layer containing an aluminum pigment, and a light diffusing layer to form a projector. Since it reflects light and effectively absorbs extraneous light and indoor illumination light, there is an excellent effect that an image projected from a projector can be viewed with high contrast even in a bright room.

Further, the reflection type screen of the present invention has a high reflection luminance and a small difference in brightness between the central portion and the peripheral portion of the screen, so that a bright and easy-to-see image can be obtained. Furthermore, since the black base material is used, the appearance of the screen becomes slightly discolored, and a high-contrast image can be obtained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing the configuration of an embodiment of a bright room reflective screen of the present invention.

FIG. 2 is an explanatory diagram showing how the light incident on the screen is reflected.

[Explanation of symbols]

 1 Black base material layer 2 Reflective layer 3 Light diffusing layer 4 Scale-like aluminum pigment

Claims (5)

[Claims] 1. A reflective screen for a bright room, which is formed by sequentially laminating a black base material layer, a reflective layer containing an aluminum pigment, and a light diffusion layer. 2. The reflective screen for a bright room according to claim 1, wherein a plastic film having a haze value of 50 or less is used as the light diffusion layer. 3. The reflective screen for a bright room according to claim 1, wherein the aluminum pigment is a scaly aluminum pigment. 4. The reflection layer is formed by alternately laminating layers containing aluminum pigment and layers not containing aluminum pigment.
The reflective screen for the bright room described. 5. The bright room reflective screen according to claim 1, wherein the reflective layer is formed by laminating a plurality of transparent films whose surfaces are printed with an ink containing an aluminum pigment.