JPS59202446A - Transmission type screen and its manufacture - Google Patents

Abstract

PURPOSE:To obtain a transmission type screen which requires no adhesive at an image part of a screen by stabilizing a yarn like material which operates as a light absorber in a groove easily without any tensile strength. CONSTITUTION:Thin and long grooves 31 are formed at dark stripes 3b on the observation surface 3 of the transmission type screen 1, and a yarn-like material 32 are inserted in those thin and long grooves 31. Then, side edge parts of a screen frame are fixed by a proper means to a guide part having a concave surface of specific curvature to curve the screen in a specific shape, and both end parts of each yarn-like material 34 fitted in a groove of the screen are fixed to edges of the screen 1 by using an adhesive 4 or fixture 4a as shown in figures.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transmission screen, and more particularly to an improvement in a transmission screen provided with a light absorption screen to improve the contrast of an image.

Various types of transmissive screens have been proposed for use in video screens of video projection televisions, etc., and some of them have already been put into practical use.

Video projection televisions project large images onto their video screens, and are primarily used for the purpose of allowing a large number of viewers to view them at once. In order to enable viewing by a large number of viewers, it is necessary to use a screen with a wide viewing angle, and a lenticular screen is preferably used for this purpose.

A lenticular screen is a screen in which a large number of elongated lenses, such as cylindrical lenses, are arranged on at least one side, with their longitudinal axes almost parallel. It refracts and focuses the light, and then diffuses and emits the light within a specific angular range from the observation surface. In this way, a lenticular screen is made up of a large number of long and narrow lenses arranged, so on the front side of the lenticular screen, there are a sub-long bright part through which light passes and a long dark part through which light does not pass, due to the refraction and focusing action of the long and thin lenses. A part is formed. In other words, in front of the lenticular screen, due to the transmitted light,
A large number of parallel bright stripes and dark stripes are generated. Generally speaking, in a transmission screen having one surface having a lens effect, the viewing surface has bright areas through which light passes and dark areas through which light does not pass.

It is preferable that the video projection screen can also be used in a so-called bright room where there is fairly bright outside light. However, when outside light hits the image area of the video projection screen, the image area that displays dark areas such as black is brightly illuminated, lowering the contrast of the image by 4 degrees.

Generally, the image contrast of a video projection screen is defined as:

In addition, B. Brightness of the bright part of the image lφAX' BM engineering N = brightness of dark areas of the image B1: Reflection brightness of external light in bright areas B2: Reflection brightness of external light in dark areas It is.

In a dark room with no outside light, contrast can be improved by increasing the ratio of BMAx/BMXN, but in a bright room affected by outside light, the reflected brightness (B1, B2) of the outside light must be taken into consideration.

In other words, in order to increase the contrast of the image on the video projection screen itself, it is necessary to suppress the reflected brightness (81, 82) of both side lights as much as possible. This is to provide a video projection screen with the function of absorbing external light, and specifically, it involves scattering light-absorbing substances on the screen base material or providing light-absorbing portions on the surface of the screen.

For example, in Japanese Utility Model Application Laid-open No. 49-3528, it is proposed to attach a light-opaque network made of photoresist to the viewing side or projection side of the screen. In this configuration, since an absorber is provided to block light, including the portion of the screen through which the light passes, the amount of light transmitted through the image is also reduced, which is not advantageous for use as this type of screen. I can't say that there is.

Furthermore, in Japanese Patent Publication No. 51-46693, a light-shielding stripe portion is provided on the opposite side of a transmissive video projection screen in which a lenticule consisting of a large number of cylindrical lenses is provided on one side through which no light passes.
It is proposed to increase the This special public service 52-4.
In the configuration of Publication No. 6693, the above-mentioned σ Utility Model Application No. 49-352
Compared to the configuration of No. 8, it is very advantageous for use as a video projection screen. This is because there is no problem of blocking the transmitted light for the 4 images.

The video projection screen disclosed in Japanese Patent Publication No. 52-46693 is provided with a photoresist film on the opposite side of the lenticular screen, and this film is exposed, developed, and dried to allow light to pass through on the opposite side. A Sumi-live pattern of a photoresist film is formed with the photoresist film left only in the areas where the light is not exposed, and an oil-based ink is coated on this stripe pattern by Off-Cera 1 printing or the like to form a light-shielding area.

However, printing oil-based ink on a striped pattern as described above requires a fairly sophisticated printing technology and requires complicated steps. This is because the stripes in the stripe pattern are very thin, and it is necessary to accurately align the ink application. In addition, the process of exposing, developing, and drying the photoresist film must be interrupted, and the production of video projection screens requires work in total darkness, complicating the manufacturing process. Since this is not good, the work must be done with extreme care, which inevitably increases the manufacturing cost.

A method of directly printing or painting the areas on the video projection screen through which light does not pass could be considered, but this would result in uneven printing and, as mentioned above, it would be difficult to paint with a narrow and uniform width.

The present applicant has already filed a patent application in 1983. - In No. 234409, an elongated groove is formed along a dark stripe portion where light does not pass, which is generated on the observation surface of a lenticular screen,
We have proposed a configuration in which filamentous materials are arranged in these elongated grooves so that the filamentous materials function as light absorbers.

The structure disclosed in Japanese Patent Application No. 57-234409 eliminates the above-mentioned drawbacks of the conventional video projection screen, and provides a transparent screen for video projection that has excellent performance, is easy to manufacture, and is inexpensive.

However, in order to ensure that the filaments are stabilized in the grooves in the many dark striped portions of the transmissive screen constructed as described above, it is necessary to tension the filaments so that they extend all the way through the groove. However, as the screen size increases, the length of the filament becomes longer, so it is necessary to apply a greater tension to the filament in order to stably lower it into the groove. The longer the length of the filament, the more likely it is that its central portion will sag, and therefore the easier it will be to escape from the vortex. For this reason, the above-mentioned Japanese Patent Application No. 57-234409 also proposes fixing the filamentous material in the vortex using an adhesive at necessary locations. However, since the central part of the filamentous material corresponds to the central part of the transparent screen, it is easily visible to the viewer, and therefore the adhesion process must be carried out with great care and skill.

The present invention provides an improved version of the transmission type screen disclosed in the above-mentioned Japanese Patent Application No. 57-234409, which allows thread-like materials to be easily and stably inserted into the grooves without applying high tension. Moreover, the present invention provides a transmissive screen that does not require adhesive bonding in the image portion of the screen.

That is, according to the present invention, the transmission screen has a projection surface and an observation surface, and at least one of the projection surface and the observation surface is formed to have a lens function,
In a transmissive screen configured so that the light projected onto the projection surface is defined on the observation surface by a large number of bright stripes through which light passes and dark stripes through which light does not pass, the light is projected along the dark stripes on the observation surface. The transmissive screen has an elongated groove and a filamentous material placed under tension in each groove, and the transmission screen itself has a curved surface on which the filamentous material is placed. A transmissive screen is provided.

According to the configuration of the present invention, the filamentous material extends under tension in an arc shape on the curved surface of the transmission screen, so that the central portion of the filamentous material is directed toward the center of the curved surface of the screen in the radial direction of curvature. A force is applied, and this force pushes the thread-like material inward into the groove of the screen, so that the thread-like material is securely fixed in the groove without the need to use adhesive or the like to fix the thread-like material in the groove. becomes possible.

With the above configuration, the filamentous material can be fixed only at the side edges of the transmission screen with adhesive or the like, which has the advantage of facilitating manufacturing.

The present invention further relates to a method for manufacturing the above-mentioned transmission screen, and according to this, the transmission screen has a projection surface and an observation surface, and at least one of the projection surface and the observation surface has a lens function. The transmission type is formed so that the light projected onto the projection surface defines a large number of bright stripes on the observation surface through which the light passes and dark stripes through which the light does not pass. A method for manufacturing a screen includes the step of providing grooves along the dark stripe portion of the viewing surface of a transmission screen, and placing a thread-like material under tension in each groove and fixing its ends to both end edges of the transmission screen. The transmissive screen constructed as described above is fitted into a screen frame having a 1' curved portion of a predetermined curvature, the side edges of the transmissive screen are fixed along the guide portions, and the viewing surface of the transmissive screen is fixed. and forming a curved surface into a curved surface.

According to the above method of the present invention, a groove is provided in advance in a flat transmission screen, a filamentous material is placed in the groove, and both ends of the filament are fixed to both edges of the transmission screen,
Next, it is only necessary to fit the transparent screen into the screen frame and fix it along the guide part to give the desired curvature, so the manufacturing method is relatively simple. Since it is hidden, a transmissive screen is provided that provides a nice appearance.

The invention will be explained in more detail below by way of example and with reference to the accompanying drawings, in which: FIG.

FIG. 1 schematically shows a video projection device, in which a transmission screen 1 of the present invention has a projection surface 2.
Projection light is projected from a video projector (P). As shown in detail in FIG. 2, the projection surface 2 is a lenticular surface provided with a number of elongated lenses 21, the longitudinal axis of which extends in the vertical direction. The projection light is refracted and condensed by the elongated lens, and is emitted from the observation surface 3 while being uniformly distributed over a predetermined angular range in the horizontal direction. Due to the refractive and condensing action of the elongated lens 21, bright stripe portions 3a through which light passes in the vertical direction and dark stripe portions 3b through which light does not pass are alternately formed in parallel on the observation surface 3.

In order to increase the contrast 1 of the image, the dark striped portion 3b is used as a light absorbing and blocking portion.In this embodiment, as can be clearly understood from FIG. In the part that becomes 3's ROQS 1 HELIVE 3b, there is a long and narrow part along this! M31 are provided, and thread-like materials 32 are inserted and arranged in these elongated grooves 31.

As can be clearly seen in FIG.
is curved so that the viewing surface 3 is convex. Both ends of the filamentous material 34 are fixed to the upper and lower edges of the transmission screen 1 using adhesive 4 or fixtures 4a, as shown in FIGS. 3a and 3b.

The transmission type screen 1 is made of a flat, uncurved object with grooves 31 and filaments 34 provided in advance as described above, and finally a concave curved surface of a predetermined curvature of the screen frame 5 as shown in FIG. The side edges of the guide portion 5a may be fixed by suitable means to give the desired curved shape. For example, as shown in FIG.
The side edges of the guide portion 5a may be aligned with the guide portion 5a and fixed to the channel 6 with screws 6a.

The transmission screen 1 is curved along the length of the filament 34, and preferably has a radius of curvature of about 2 m to 12 m. 2 If the radius of curvature is less than II+, the transparent image becomes distorted and protrudes toward the viewer, giving a feeling of oppression.
Also, it becomes difficult to adjust the focus of the image. Also, if the radius of curvature is larger than 12n+, depending on the size, the filamentous material 3
4 in the groove 31 cannot be obtained.

Since it is possible to fix the filamentous material 34 only at the upper and lower edges of the transparent screen 1, there is no need to use adhesive or the like on the area to be imaged, and the fixing points at the upper and lower edges of the screen can be reduced. , because it is hidden by screen frame 1,
A transparent screen with good appearance will be provided.

The transmission screen used in the present invention is manufactured by extrusion molding, hot pressing, or injection molding of materials such as acrylic resin, vinyl chloride resin, olefin resin, and styrene resin.

Therefore, the large number of elongated grooves formed on the observation surface of the above-mentioned transmission screen can be easily formed at the same time as the lens action surface.

Arranging the filamentous materials in the large number of elongated grooves can be done easily by arranging the filamentous materials in advance at intervals equal to the spacing between the elongated grooves.

The thread-like material 32 used in the present invention is not particularly limited as long as it has light absorption ability and a predetermined strength. For example, spun yarn or filament yarn of natural fibers or synthetic fibers that are dyed in a dark color are common, but instead of these fiber yarns, metal 111 such as aluminum
I-fibers, ultra-fine metal filaments, etc. can be used.

In addition to the cross-sectional shape shown in FIG. 2, the cross-sectional shape of the transparent screen 1 may be as shown in FIGS. 6, 7, and 8. A lenticular lens surface is also provided on the observation surface 3 of the transmission screen 1 in the figure, and grooves 31 are defined between each lenticular lens body in which a filament 34 is disposed.
A lenticular surface is provided on the observation surface 3, and a Fresnel lens 22 is provided on the projection surface 1. A lenticular lens surface 31 is defined between 35 degrees and 36 degrees of lenticular lens surfaces constituting the lenticular surface. These lens bodies 35 and 36 are
The inclined surfaces on both sides of each lens are total reflection surfaces, and no light is emitted from these surfaces, forming a dark stripe portion. Regarding the transmission type screen provided with a lenticule having such a lens body 35.36, Japanese Patent Application No. 56-51194 and Japanese Patent Application No. 56-9189 filed by the same applicant
No. 6, Patent Application No. 1984-212584, Patent Application No. 1982-29
No. 178 and Japanese Patent Application No. 57-59389, the constructions of these lens bodies 35 and 36 are not directly related to the present invention, so a detailed explanation thereof will be omitted. Further, the Fresnel lens 22 provided on the projection surface 2 has the effect of refracting the light incident on the projection surface 2 into parallel light and condensing the light onto a predetermined location on the observation surface 3. This helps maintain the brightness, especially around the screen, and makes the screen uniform in brightness.

Furthermore, in another configuration shown in FIG. 9, a Fresnel lens sheet 7 is combined with the transmission type screen 1 having the configuration shown in FIG.

Example A transmission screen 1 provided with lenticules having the configuration shown in FIG. 180°C1 pressure 40 Kl/cm2
) was formed. The structure of the lenticular lens body of the transmission screen 1 is shown in detail in FIG. The transmission screen 1 was obtained in the form of a flat plate with a size of 920 mm x 750 mm.

Nylon silkworms dyed black with a wire diameter of 0.235 mm were used as the filament 34, which were arranged and wound in the same manner as the warping beam. Next, the wound yarn was spread out through a guide jig provided with guides at intervals of 1 to 2 mm corresponding to the width of the dark stripe, and both ends were held. Push the transmission screen 1 from above the threads arranged in this state, and wrap the threads 34 around the transmission screen 1 as shown in FIG. I used epoxy adhesive 4 to fix the parts.

Next, as shown in Figure 12, the dimensions, that is, the external dimensions are 95
0mm x 75 oH internal mounting is 90On++nx700m
It was fitted into the screen frame 5 of No. m and fixed to the frame 5 with the channel 6 and screws 6a (see Fig. 5).

In this case, the guide portion 5a of the screen frame 5 is
The depth of the arc should be 60 mm (see Figure 13).

With the above configuration, the thread 34 was reliably held in the groove 3 of the observation surface 3 of the transmission screen 1.

Although the present invention has been described above using the embodiments, the main scale and brightness are not limited to the above embodiments, and can be variously modified within the scope of the claims.

[Brief explanation of the drawing]

FIG. 1 is a perspective view schematically showing an example of the use of the transmission screen of the present invention. FIG. 2 is a cross-sectional view of the transmission screen of FIG. 1; FIGS. 3a and 3b are diagrams showing details of the upper edge of a vertical cross-sectional view of the transmission screen. FIG. 4 is a diagram illustrating a screen frame for a transmissive screen in a perspective view. FIG. 5 is a partially perspective view showing the state in which the transmission screen is fitted into the screen frame. FIGS. 6 to 8 are cross-sectional views similar to FIG. 2, showing other configurations of the transmission screen. FIG. 9 is a perspective view showing still another configuration of the transmission screen. 10 to 13 illustrate the configuration of an embodiment of the transmission type screen of the present invention, and FIG. 10 is a cross-sectional view showing in detail the configuration of the lenticular lens body of the transmission type screen. Yes, and FIG. 11 is a longitudinal sectional view thereof. 12th
The figure is a perspective view of the screen frame, and FIG. 13 is a diagram showing a longitudinal cross-sectional view thereof. DESCRIPTION OF SYMBOLS 1... Transmission screen, 2... Projection surface, 3... Observation surface, 3a... Bright stripe part, 3b... Dark stripe part, 4... Adhesive, 5... Screen frame, 6... Di\7 channel, 6a... Screw, 7... Fresnel lens sheet, 21... Elongated lens, 22... Fresnel lens, 31... Groove, 34... Thread-like material, 35.36...Lens body. Agent Akira Asamura Figure 1 Figure 22 Figure 3Q Figure 3B Figure 4 Figure 6 Off-line Figure 8 Figure 9 Figure 10 Figure 11 Hill 5 Crime

Claims (1)

[Scope of Claims] (1) A transmission screen having a projection surface (2) and an observation surface (3), which have a projection surface (2) and an observation surface (3).
At least one surface of the projection surface (2) is formed to have a lens effect, and the light projected onto the projection surface (2) is reflected onto the observation surface (3).
), the viewing surface (3) is darkened by a transmission screen (1) configured to define a large number of bright stripe portions (3a) through which light passes and dark stripe portions (3b) through which light does not pass. The elongated striped part (3b)! :5 (31) and a filament (34) placed under tension in the trapezoid (31), and the transmission screen (1) has a surface on which the filament (34) is placed. A transmission screen characterized by having a curved surface. (2. In the transmission screen according to claim (1), the transmission screen (1) is a transmission type characterized in that the transmission screen (1) has a curved surface with a radius of curvature of 21Tl to 12m. Screen. (3) The transmission screen according to claim (1), characterized in that a lenticular lens body (21) is provided on the projection surface (2) to have a lens effect. (4) In the transmission screen according to claim (1), lenticular lens bodies (33, 35, 36 ). (5) Claim (1) or (4)
In the transmission screen described in 2.
A transmissive screen characterized in that a Fresnel lens (22) is provided in (). (6) In the transmission screen according to claim (1), the observation surface (3) and the projection surface (2)
) is provided with lenticular lens bodies (21, 33). (7) Claims (1) to ff1(6)
In the transmission screen according to item 1, the filamentous material (3
1, 34) is a transmission screen characterized in that it is at least partially bonded. (8) A method for manufacturing a transmission screen, wherein the transmission screen has an observation surface and a projection surface, and
At least one of the east surface and the projection surface is formed to act as a lens, and the light projected onto the projection surface has many bright striped portions through which the light passes and dark striped portions through which no light passes. A method for manufacturing a transmission screen configured to define a transmission screen, comprising the steps of: providing grooves along the dark screen 1 to live portions of the observation surface of the transmission screen, and inserting a filament under tension into each groove. and fixing both ends thereof to both ends of the transmissive screen; fitting the transmissive screen thus constructed into a screen frame having a guide portion of a predetermined curvature;
A method for manufacturing a transmission screen, comprising the steps of: fixing a side edge of the transmission screen along the guide portion; and forming a curved viewing surface of the transmission screen.