JP2624462B2 - Shade plate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light-shielding plate, and more particularly to a light-shielding plate attached to a display surface of a display device and used to block external light from entering the display surface.

[0002]

2. Description of the Related Art Display devices such as CRT display devices and LED display devices have been actively adopted in various devices. In order to make the display on these display devices easy to see, it is necessary to form a bright and high-contrast image. Of these, to obtain a bright image, CR
The brightness of T or the LED may be increased. This can be achieved by, for example, making an attempt to improve the quantum yield of the phosphor screen in the case of a CRT, and improving the device itself such as developing an element that operates with high power in the case of an LED.

On the other hand, in order to obtain an image with high contrast, the ratio between the white level and the black level of the image may be improved. The larger the ratio, the clearer and more easily an image can be seen. Here, first, considering what factors determine the white level, the white level is determined by the luminance of the display device. That is, the highest light emission illuminance or luminance per unit area of the display surface corresponds to the white level. On the other hand, the black level is determined by the brightness of the room where the device is placed, regardless of the brightness of the display device itself. That is, if there is a so-called room light in the surroundings, the light is illuminated by this light and the display surface of the device has a predetermined illuminance. Thus, while the white level is substantially determined by the performance of the display device, the black level varies with the brightness of the room. In order to obtain a high-contrast image, it is necessary to increase the difference between the white level and the black level, that is, to darken the room. This is one of the major drawbacks of the conventional display device, which causes the image to be whitish and unclear as a whole in a bright room.

In order to be able to obtain a clear image even in a bright room, keeping the black level low even in a bright room is the only fundamental solution. One way to keep the black level low is to block room light from the display surface. For example, a light control film developed by 3M USA has a property of blocking room light from a display surface. FIG. 3 shows a light-shielding principle diagram of this light control film. The light control film 4 has a structure in which transparent bodies 5 and black films 6 are alternately arranged, and has a so-called window blind shape. If this is arranged on the display surface of the display device, for example, the LED element 7, the light 8 from the LED element 7 passes through the light control film 4 and reaches the viewpoint 9; Light 11
Is shielded by the black film 6 and does not reach the LED element 7. Therefore, the black level of the LED element 7 is kept low irrespective of the lighting 10 in the room, and the contrast when viewed through the light shielding plate can be improved.

[0005]

However, the conventional light-shielding plate such as a light control film has a disadvantage that the manufacturing cost is extremely high. In order to manufacture a light control film, a process of forming a multilayer body by alternately stacking and bonding the transparent body 5 and the black film 6 and then cutting and polishing the multilayer body is required, and much labor and time are required. Costly and ultimately the manufacturing costs are very high.

The present invention has been made in view of the above circumstances, and has as its object to provide a light-shielding plate capable of reducing labor and time in a manufacturing process and reducing manufacturing costs.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and is provided with a light-shielding plate installed between an observation target and an observation point to block external light from entering the observation target. There are a plurality of transparent plates or half plates each having a main surface through which light traveling from the observation target to the observation point passes and having a large number of parallel microprojections having transparent microsurfaces integrally formed on the surface. A side plate is formed on the parallel minute protrusions so as to be substantially perpendicular to the main surface, and an opaque light-shielding portion is formed on the side surface. A layer is formed, and among the surfaces of the plurality of transparent plates or translucent plates, a surface facing at least one side on the observation target side or the observation point side is a flat surface. It is characterized by the following.

[0008]

According to the structure described above, light from the outside is shielded by the opaque layer and does not reach the observation target, for example, the display surface of the display device. That is, the plurality of transparent plates or translucent plates on which the opaque layer is formed function as louvers, and function to transmit only light from the display surface of the display device. In this case, since a flat surface is formed on at least one of the plurality of transparent plates or translucent plates, the mounting can be easily performed without impairing the optical effect.

As described above, blocking the light from the outside has an effect of keeping the black level low even in a bright environment, and a clear image with high contrast can be obtained even in a bright room.

[0010] Further, since the opaque layer is formed on the side surface of the minute protrusion, a concave portion is necessarily formed between the opaque layers. Since external light incident on the concave portion is almost absorbed by the opaque layer, surface reflection can be reduced accordingly.

Moreover, a transparent plate or a translucent plate having a minute surface can be easily manufactured by integral molding, and an opaque layer can be easily formed by painting or a photosensitive process, so that the manufacturing cost is greatly reduced. can do.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. FIGS. 1A to 1D show an embodiment of a light shielding plate according to the present invention, in which two transparent plates 1 and 1 'are combined to form a light shielding plate. In the drawing, only a part of the light shielding plate is shown.

In FIG. 1 (a), a transparent plate 1 is integrally formed of, for example, an acrylic resin or the like, and has a large number of parallel microscopic surfaces having transparent microscopic surfaces (hereinafter, simply referred to as microscopic surfaces) 3. A ridge is provided on the surface. A side surface portion is formed on the parallel small protrusions so as to be substantially perpendicular to the main surface, and an opaque layer 2 having a light shielding property is formed on the side surface portion. Here, the main surface of the transparent plate 1 is a surface through which light from the observation target to the observation point passes, and a surface having a spread when viewed macroscopically. The surface of the opaque layer 2 may be a reflective surface, but is preferably a non-reflective surface in order to enhance the light blocking effect. In order to form the opaque layer 2, for example, a minute surface to be formed is chemically treated or sand is blown into a so-called satin-like shape, and a matte black paint is easily applied from above. Can be implemented. Since the surface of the transparent plate 1 is also roughened by the rough surface treatment, the formed opaque layer 2 is a non-reflective surface on both sides. FIG. 2 shows such a transparent plate 1.
FIG.

On the other hand, a transparent plate 1 'which is opposed to the transparent plate 1 at a slight distance also has an opaque layer 2' and a minute surface 3 '. The transparent plates 1 and 1 'are arranged such that the concave and convex portions formed by the respective parallel minute protrusions are alternately arranged. As described above, when the transparent plate 1 and the transparent plate 1 'are arranged slightly apart from each other, most of the light obliquely incident on each of the main surfaces is transmitted to any one of the opaque layers of the transparent plates 1 and 1'. 2, 2 ', and a high light-shielding effect can be obtained.

Since the rear side of the transparent plates 1 and 1 ', that is, the side on which the minute ridges are not formed, is a flat surface, the flat surface is used as a glass surface or a plastic surface on the mounting member side. It can be easily attached in close contact. If the rear side is not a flat surface and small projections are formed on the rear surface, an air layer exists in a closed space formed by the glass surface and the concave portion between the small projections. Therefore, the refractive index of light that should not be shielded is affected. However, such an influence can be eliminated by setting the flat surface on the back side as the mounting surface.

If the light-shielding plate as described above is installed on the front surface of the display device, for example, so that the main surfaces of the transparent plates 1 and 1 'and the display surface of the display device are parallel, the light from the display device will Although the light passes through the minute surfaces 3 and 3 'to the observation point, most of the external light from the surrounding environment is blocked by the opaque layers 2 and 2' and does not reach the display surface of the display device. That is, most of the light passing through the transparent plate 1 is occupied by light emitted from the display device. Therefore, the black level of the image formed on the display surface of the display device is kept low even when used in a bright environment, and a clear image with high contrast can be obtained. The opaque layers 2, 2 '
Are provided at a fine pitch of, for example, about 0.2 mm. When the light-shielding plate is observed with the naked eye, the stripes formed by the opaque layers 2 and 2 ′ do not adversely affect the image on the display device. .

FIG. 1B shows a structure in which the transparent plates 1 and 1 'arranged as shown in FIG. 1A are brought close to each other, and finally fitted and fixed so as to abut each other. In this case, the opaque layer need only be formed on one of the transparent plates 1 and 1 '. FIG. 1B shows an example in which the opaque layer 2 is formed only on the transparent plate 1. According to the structure shown in FIG. 1B, almost the same optical effect as that of the conventional example shown in FIG. 2 can be obtained, and furthermore, steps such as cutting and polishing of a multilayer body are eliminated. It can be greatly reduced.

FIG. 1C shows the opaque layer 2 of FIG. 1B formed longer. According to this, the light shielding effect can be further enhanced.

FIG. 1 (d) shows one of the transparent plates 1 fitted and fixed to the transparent plate 1 ', in which the minute surface 3 is inclined. In this case, the right transparent plate 1 '
Is a mounting surface. Since the transparent plate 1 is formed by integrally molding an acrylic resin or the like, the reflection of light is considerably likely to occur on the surface. , And the influence of reflected light can be avoided.

The above examples are only examples of the present invention, and various other combinations are possible. For example,
The pitch at which the minute surfaces 3, 3 'of the transparent plates 1, 1' are formed may be changed, and the opposing minute surfaces need not be parallel to each other. When the two transparent plates 1 and 1 'are combined as described above, the manufacturing process is very simple, since the respective transparent plates are manufactured by integral molding and then the fixing operation is performed. In the above-described embodiment, an example is described in which the light shielding plate is configured by combining two transparent plates. However, three or more transparent plates may be used.

The light-shielding plate according to the present invention can be used not only for a display device but also as a blind by being attached to a window. At this time, if a translucent plate containing particles that scatter light is used instead of the transparent plate 1, it can be used as a light-receiving plate having a soft touch. Furthermore, if projector light is projected on this transparent plate or translucent plate, it is possible to fulfill the function as a screen.

[0022]

As described above, according to the present invention, a large number of parallel small ridges having a transparent small surface are integrally formed on the surface of a transparent plate or a transparent plate. Has a configuration in which side surfaces are formed so as to be substantially perpendicular to the main surface, and an opaque layer having a light-shielding property is formed on the side surfaces, so that a reduction in contrast due to external light can be effectively prevented. it can. In particular, since the opaque layer is formed on the side surfaces of the parallel small ridges, a concave portion is inevitably formed between the opaque layers, so that surface reflection of external light can be reduced.

In the present invention, since the light shielding plate is constituted by a plurality of transparent plates or translucent plates, much of the light obliquely incident on the main surface can be shielded, and a high light shielding effect can be obtained. Can be obtained.

Further, by forming the minute projections integrally on the transparent plate or the translucent plate, the transparent minute surface and the opaque layer can be formed on the same member, thereby facilitating the production and reducing the production cost. be able to.

Further, according to the present invention, since at least one of the plurality of transparent plates or translucent plates has a flat surface, the mounting can be easily performed without impairing the optical effect. .

[Brief description of the drawings]

FIG. 1 is a side view showing an embodiment of a light shielding plate according to the present invention.

FIG. 2 is a perspective view showing the appearance of a transparent plate in FIG.

FIG. 3 is a diagram illustrating the principle of a light blocking function of a conventional light blocking plate.

[Explanation of symbols]

 Reference Signs List 1, 1 'transparent plate 2, 2' opaque layer 3 microscopic surface 4 light control film 5 transparent body 6 black film 7 LED element 8 light from LED element 9 viewpoint 10 room lighting 11 light from room lighting

Claims (9)

(57) [Claims] 1. A light-shielding plate installed between an observation target and an observation point for blocking external light from entering the observation target, wherein a main surface through which light traveling from the observation target to the observation point passes is provided. Along with, a large number of parallel micro-projections having transparent micro-surfaces are integrally formed on the surface, comprising a plurality of transparent plates or translucent plates. Side surfaces are formed so as to be substantially perpendicular to the main surface, and an opaque layer having a light-shielding property is formed on the side surfaces, and the surfaces of the plurality of transparent plates or semi-transparent plates are formed. Of which
A light-shielding plate, wherein a surface facing at least one of the observation target side and the observation point side is a flat surface. 2. The method according to claim 1, wherein the transparent micro surface of at least one of the plurality of transparent plates or the translucent plate has an inclination angle with respect to the main surface of the transparent plate or the translucent plate. The light shielding plate according to claim 1. 3. The light-shielding plate according to claim 1, wherein said transparent minute surface is parallel to a main surface of said transparent plate or translucent plate. 4. The light-shielding plate according to claim 1, wherein the transparent minute surface is formed only on one side of the transparent plate or the translucent plate. 5. The apparatus according to claim 1, wherein the parallel minute projections are made of two transparent plates or semi-transparent plates fitted in a state of being opposed to each other. Shading plate. 6. The light-shielding plate according to claim 1, wherein the transparent plate or the translucent plate is made of an acrylic resin. 7. The light-shielding plate according to claim 1, wherein the translucent plate contains particles that scatter light. 8. The light-shielding plate according to claim 1, wherein the opaque layer is made of a matte black paint. 9. The light-shielding plate according to claim 1, wherein the surface of the opaque layer has a matte rough surface.