JP2002023268A - Transmission screen - Google Patents

Abstract

PROBLEM TO BE SOLVED: To readily enlarge the visual field angle of an image displayed on a transmission screen, in an image display device such as the liquid crystal television of a rear projection type. SOLUTION: In this transmission screen, for which light is made incident from a light incident surface 11a on one surface of a light transmissive plate material 11 and the light is emitted from a light emission surface 11b on the opposite side of the light incident surface 11a, projected parts 12, constituted of a light transmissive material different from the light transmissive plate material 11, are provided on at least one of the light incident surface 11a and the light emission surface 11b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmissive screen used for a rear projection type image display device such as a liquid crystal television, and more particularly to a transmissive screen which can easily increase a viewing angle of an image displayed on the transmissive screen. It is characterized in that it can be performed in a short time.

[0002]

2. Description of the Related Art Heretofore, in a rear projection type image display device such as a liquid crystal television, a transmission screen has been used to display an image.

Here, in such a transmission type screen, it is necessary to make it possible to view images from various directions.

[0004] For this reason, conventionally, a lens sheet such as a lenticular sheet is adhered to one surface of a light-transmitting plate, a light-transmitting plate having a surface provided with irregularities by mechanical processing, or a metal sheet. In general, a mold having irregularities provided on one side of a light-transmitting plate at the time of molding has been used.

However, as described above, a lens sheet such as a lenticular sheet is adhered to one surface of the light-transmitting plate material,
Problems such as providing irregularities on one side of a translucent plate material by mechanical processing, or providing irregularities on a mold and providing irregularities on one side of a translucent plate material during molding are troublesome and costly. was there.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems in a transmission screen used for a rear projection type image display device such as a liquid crystal television. It is an object of the present invention to easily expand a viewing angle of an image displayed on a screen.

[0007]

In the present invention, in order to solve the above-mentioned problems, light is incident from one light incident surface 11a of the light transmitting plate 11 and is opposite to the light incident surface 11a. In the transmissive screen from which light is emitted from the light exit surface 11b, at least one of the light entrance surface 11a and the light exit surface 11b is made of a light transmissive material different from the light transmissive plate material 11. The projection 12 is provided.

Then, as in the transmission screen of the present invention, at least one of the light entrance surface 11a and the light exit surface 11b of the light transmitting plate 11 is made of a light transmitting material different from the light transmitting plate 11. When the formed protrusion 12 is provided, light incident on the light transmitting plate 11 from the light incident surface 11a and light emitted from the light output surface 11b of the light transmitting plate 11 are diffused in the protrusion 12, Light is uniformly emitted from the light emitting surface 11a in various directions, and images displayed on the transmissive screen can be seen well from various directions.

In providing the projections 12 made of a light-transmitting material on the light entrance surface 11a and the light exit surface 11b as described above, the type of the light transmission material used for the projections 12 is not particularly limited. However, in general, a light-transmitting resin different from the light-transmitting plate material 11 is used, and in general, light is diffused well at the projecting portion 12 and light is uniformly emitted from the light emitting surface 11a in various directions. It is preferable that a material having a lower refractive index than that of the translucent plate 11 is used for the protrusion 12. In special applications, such as when it is necessary to obtain a distribution of light centered in a direction perpendicular to the light exit surface 11b, a material having a higher refractive index than the light-transmitting plate 11 is used for the protrusion 12. Is used.

In addition, the light entrance surface 11a and the light exit surface 1
When the projection 12 made of a light-transmitting material is provided on the projection 1b, light is diffused in various directions and emitted more uniformly from the light emitting surface 11b. It is preferable to add fine particles.

In the transmission screen according to the present invention, the light entrance surface 11a and the light exit surface 1
When the projection 12 made of a light-transmitting material is provided on at least one surface of the projection 1b, the projection 12 is formed by printing.

When the projections 12 are formed by printing as described above, the projections 12 having various shapes and arrangements can be easily provided on the light entrance surface 11a and the light exit surface 11b.

When the projections 12 made of a translucent material are provided on the light entrance surface 11a and the light exit surface 11b by printing, the light entrance surface 11a and the light exit surface 11b are made of a transparent resin. After printing using a monomer, oligomer, or terpolymer, the monomer, oligomer, or terpolymer is polymerized to provide the protrusion 12, or printing is performed using a solution in which a translucent material is dissolved in a solvent. After that, the protrusion 12 can be provided by evaporating the solvent.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a transmission screen according to an embodiment of the present invention will be specifically described with reference to the accompanying drawings.

In the transmission screen of this embodiment, as shown in FIGS. 1A and 1B, a translucent resin such as polymethyl methacrylate resin, polycarbonate resin, poly-4-methylpentene-1, and polylactic acid is used. In the light-transmitting plate member 11 configured as described above, a projection 12 made of a light-transmitting resin is provided on the light-emitting surface 11b opposite to the light-entering surface 11a on which light is incident.

Here, in the transmission type screen of this embodiment, the projection 12 having a circular planar shape and an arc-shaped cross section is formed vertically and horizontally on the light emitting surface 11b with a required interval. There are many arrangements.

In the transmissive screen of this embodiment, the projection 1 having a circular flat surface is formed on the light emitting surface 11b.
2, the planar shape of the projection 12 is not limited to a circle, but may be any shape such as an ellipse or a square, and the cross-section of the projection 12 may be an arc. The shape is not limited, and may be, for example, any shape such as a square shape or a triangular shape.

The size of the projection 12 provided in this way is not particularly limited, but the light incident from the light entrance surface 11a and guided to the light exit surface 11b is appropriately diffused in the projection 12 In order to uniformly emit light from the light emitting surface 11b in various directions, the diameter and the length of one side of the protrusion 12 are preferably set to 5 mm or less, more preferably 1 mm or less, and The height of the protrusion 12 is set to be 10 μm or more, preferably 30 μm to 2 μm.
mm, more preferably in the range of 30 μm to 1 mm. In this embodiment, the light emitting surface 11
Although the size of the protrusions 12 provided at b is fixed, it is also possible to provide protrusions 12 of different sizes.

In providing a large number of protrusions 12 on the light exit surface 11b as described above, the area ratio of the protrusions 12 to the light exit surface 11b is not particularly limited, but the light enters the light exit surface 11a and enters the light exit surface 11b. In order for the guided light to be appropriately diffused in the projections 12 and to uniformly emit light from the light emitting surface 11b in various directions, the area ratio of the projection 12 to the light emitting surface 11b is set to 25. % Or more, preferably 50% or more.

Further, in the transmissive screen of this embodiment, a large number of projections 12 are arranged on the light emitting surface 11b vertically and horizontally at a required interval, but a large number of projections 12 are provided at random. It is also possible to do so.

The type of the translucent resin used for the protrusion 12 and the method of forming the protrusion 12 on the light emitting surface 11b are not particularly limited, but a mask having a hole corresponding to the protrusion 12 may be used. If the projections 12 are provided by printing using a not-shown), a large number of projections 12 can be easily formed at once, and the productivity of such a transmissive screen is improved. When the projections 12 are provided on the light emitting surface 11b by printing in this manner, printing can be performed a plurality of times in order to increase the area ratio of the projections 12 to the light emitting surface 11b as described above. When the projections 12 are provided by printing using a mask as described above, the three-dimensional shape of the projections 12 can be controlled by changing the timing and speed at which the mask is detached.

The light-emitting surface 1 is thus printed by printing.
In providing the protrusion 12 in 1b, a monomer or oligomer or terpolymer of a thermosetting or photocurable resin is used,
After printing is performed on the light emitting surface 11b as described above, the above-described monomer, oligomer, or terpolymer is cured to provide the protrusion 12, or printing is performed using a solution in which a translucent material is dissolved in a solvent. After performing the above, the protrusions 12 can be provided by evaporating the solvent. Here, as the heat or photo-curable resin, a known light-transmitting resin can be used, and for example, an epoxy resin or the like can be used. Examples of the light-transmitting material dissolved in the solvent as described above include light-transmitting materials such as polymethyl methacrylate resin, polycarbonate resin, poly-4-methylpentene-1, and polylactic acid used for the light-transmitting plate 11 described above. A transparent resin, a derivative of these translucent resins, and a mixture thereof can also be used, and there is no particular limitation as long as it is a translucent resin that can be dissolved in a solvent.

In the transmissive screen of this embodiment, light is incident on the translucent plate 11 from the light incident surface 11a, and the light is transmitted to the large number of projections 1 as described above.
When each of the projections 12 is guided to the light emitting surface 11b provided with
Is diffused, and the light is uniformly emitted from the light emitting surface 11b in various directions, so that the image displayed on the transmissive screen can be seen well from various directions.

In this embodiment, the light emitting surface 11b is provided with the circular projections 12 as described above. However, as shown in FIGS. 2A and 2B, A large number of linear projections 12 may be provided on the light emitting surface 11b, and the same effect can be obtained in this case.
Further, although not shown, it is also possible to provide the line-shaped protrusions as described above so as to intersect, or to combine the line-shaped protrusions with the dot-shaped protrusions. .

In the above embodiment, the projection 12 made of the light-transmitting material as described above is connected to the light exit surface 11b.
However, it is also possible to provide such a protrusion 12 only on the light incident surface 11a, or to provide it on both the light exit surface 11b and the light incident surface 11a.

In the above embodiment, only the projection 12 made of a translucent material is provided. However, if light diffusing fine particles are dispersed in the projection 12, The light is further diffused in various directions in the portion 12, and the light is more uniformly emitted from the light emitting surface 11b in various directions.

[0027]

As described in detail above, in the transmissive screen according to the present invention, at least one of the light-entering surface and the light-exiting surface of the light-transmitting plate is provided with a light-transmitting material different from the light-transmitting plate. In order to provide a protrusion made of a material, in this protrusion, light incident on the light-transmitting plate from the light-entering surface, and light emitted from the light-emitting surface of the light-transmitting plate are diffused, Light is uniformly emitted from the light emitting surface in various directions, and images displayed on the transmission screen can be seen well from various directions.

In the transmission screen according to the present invention, a projection made of a light-transmitting material is provided on at least one of the light-entering surface and the light-emitting surface of the light-transmitting plate by printing. Protrusions having various shapes and arrangements can be easily provided on the light entrance surface and the light exit surface.

In the transmission screen according to the present invention, when the projection is made of a material having a lower refractive index than that of the light-transmitting plate, or when light-diffusing fine particles are added to the projection, the projection is formed. The light was further diffused in the portion, and the light was more uniformly emitted from the light emitting surface in various directions, so that the image displayed on the transmissive screen could be more clearly seen from various directions.

[Brief description of the drawings]

FIG. 1 is a front view and a side view of a transmission screen according to an embodiment of the present invention.

FIG. 2 is a front view and a side view of a transmission screen according to another embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 11 translucent plate material 11a light entrance surface 11b light exit surface 12 protrusion

Claims (7)

[Claims] 1. Light is incident from one light incident surface 11a of a light transmitting plate 11, and the light exit surface 1 on the opposite side of the light incident surface 11a.
1b, a projection 12 made of a light-transmitting material different from the light-transmitting plate 11 is provided on at least one of the light-entering surface 11a and the light-emitting surface 11b. A transmission screen characterized by comprising: 2. Light is incident on one of the light incident surfaces 11a of the translucent plate 11, and the light exit surface 1 on the opposite side of the light incident surface 11a.
In a transmissive screen from which light is emitted from 1b, at least one of the light entrance surface 11a and the light exit surface 11b is provided with a projection 12 made of a translucent material by printing. Transmissive screen. 3. The transmissive screen according to claim 1, wherein the projections are made of a translucent resin different from the translucent plate material. 4. The transmissive screen according to claim 1, wherein the refractive index of the light at the projecting portion is smaller than the refractive index of the light at the translucent plate material. A transmission screen characterized by the above. 5. The transmissive screen according to claim 1, wherein at least one of the light entrance surface 11a and the light exit surface 11b has a pointed projection 1.
2. A transmissive screen characterized in that a large number of 2 are formed. 6. The transmission screen according to claim 1, wherein at least one of the light entrance surface 11a and the light exit surface 11b has a linear projection 12. A transmission screen characterized by being formed in a large number. 7. The transmission screen according to claim 1, wherein light-diffusing fine particles are added to said projections.