JPH0422502B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method of assembling and configuring a transmissive projection screen used in projection televisions and various projection devices, and in particular, relates to a method for assembling and configuring a transmissive projection screen used in projection televisions and various projection devices, and in particular, to prevent large-sized images from becoming an eyesore. The purpose is to support the screen by specifying the shape and position of the pillars.

(Prior Art) A conventional transmission type projection screen is, for example, a so-called one-piece screen, as shown in FIG. The Kyura lens 12a is provided with a molded body of a transparent synthetic resin with excellent optical properties, such as acrylic resin, vinyl chloride resin, styrene resin, polycarbonate resin, acrylonitrile-styrene copolymer resin, etc. A device that can accurately maintain the relative position of both lenses is known, and because it can accurately maintain the relative position of both lenses, the cost is low and it has been put into practical use, but it is limited to a size below a certain size due to manufacturing technology. It is something.

Furthermore, as shown in FIG. 9, a so-called two-piece screen is also known in which a Fresnel lens sheet 11b and a lenticular lens sheet 12b are each manufactured separately from the synthetic resin and then combined and pasted together. However, since lenticular lens sheets have semicylindrical lenses, they are relatively easy to form into long lengths, whereas Fresnel lens sheets, like the one-piece sheet mentioned above, have a limit in size due to molding, so it is difficult to improve their optical properties. Large screens have not been put into practical use because the technology to fully utilize them has not yet been developed.

Currently, large-sized projection screens are desired for movies, television, etc. For example, in movies, 70
Projecting mm film images onto a large screen,
Even in the case of television images, there is a system called multi-screen, in which many screens are lined up to display a single screen overall.

For such screens, transmissive screens have a much higher utilization rate of projection light, and a greater degree of freedom in designing the directional distribution of the transmitted light flux from the projection screen surface toward the audience. On the other hand, reflective screens are considered to be the same as printing pictures and have a narrow dynamic range, so even if the amount of projection light or irradiation light is increased, Even if you increase the brightness, the highlights become brighter and the dark areas also become brighter, which does not lead to an increase in dynamic range, in contrast to the wide dynamic range of color slide transparencies, which also loses the wide dynamic range.

When making a large screen by combining such transparent screens, an appropriate unit size is used depending on factors such as the materials used, processing machinery, convenience of handling, transportation, transportation, assembly and installation methods, etc. It is necessary to assemble huge structures.

(Problem to be solved by the invention) However, until now, when the joint is supported using a regular square or round material, generally speaking, even if this supporting material is used on the incident side of the screen, the incident light flux cannot be controlled. As a result of blocking, the area left a strong impression as a seam, which prevented its practical use.

(Means for Solving the Problems) The present invention was made in view of the above-mentioned circumstances, and it is possible to arrange a plurality of transmission screen units on the same plane.
Or, when they are arranged adjacently on the curved surface of the same arc so that there are vertical and/or horizontal joints to form one large screen, the blind spot of the light rays incident on the joints of the screen , a triangular prism (a prism with a triangular part) having an apex angle less than or equal to the angle of this blind spot according to the continuity of screen units.
The same applies hereinafter) and/or triangular cross beams (referring to girders with triangular parts; the same applies hereinafter) are used, and these are provided close to the joints of the screen, thereby supporting the screen. Transparent for large screens. This is a method of constructing a type screen.

(Function) A triangular prism with an apex angle less than the angle of the blind spot is used as a support or a triangular crossbeam in the blind spot of the transmissive screen, so vertical or horizontal seams are not displayed too thickly, making it easy to recognize the joints on the large screen. You can enjoy watching the screen without being conscious of it, freeing yourself from that annoyance.

(Example) Embodiments of the present invention will be described with reference to the drawings.

When the screen units are arranged horizontally in a straight line, the two transmission screen units A ₁ and A ₂ are arranged horizontally on the same plane as shown in the top view of Fig. 1 and the perspective view of Fig. 2. Connecting.

In this case, the projectors L ₁ and L ₂ are adapted to send partial images to their respective screen units A ₁ and A ₂ , respectively.

The transmission screen units A ₁ and A ₂ each have a width W
Then, the projection distance P (distance between the projection lenses O ₁ , O ₃ of the projector and the positions O ₂ , O _{4 of the transmissive screen), the viewing distance D (the distance between the projection lenses O 1 , O 3 of the projector and the positions O 2 , O 4} of the transmissive screen), the viewing distance D (the distance between the projection lenses O _{1 , O 3 of the projector and the positions O 2} , O ₄ of the transmissive screen and the planned audience) (distance from representative location AU).

The line connecting O ₂ and O ₄ is the transmission screen unit A ₁ ,
The points that intersect with the edges of A ₂ are C ₀ , C ₁ and C ₂ (however, C ₀ is A ₁ ,
(common to A ₂ ), C ₁ C ₀ C ₂ is the horizontal line Y ₁ , Y ₂ connecting the centers of the screen, and X ₁ , X ₂ are the joints of the transparent screen units A ₁ , A ₂ This is the vertical line at the top. Also, Z ₁ Z ₂ passes through C ₀ and the above X ₁ , X ₂ and
It is a line perpendicular to Y ₁ and Y ₂ . When doing this, the projection angles of the projection lenses O ₁ and O ₃ are 2α and AU, respectively.
The viewing angle of is 2γ, the angle O ₁ C ₀ Z ₁ = α, the angle O ₃ C ₀ Z ₁
= α, so the blind space on the projector side is 2α,
AUC ₀ Z ₂ becomes the angle γ.

Therefore, there is a triangular prism with an apex angle of 2α or less in the blind space.
If you connect and support a transparent screen using Ta,
The screen can be supported without visual appeal to the seams between the units of the transmissive screen.

When arranging the transmissive screen units vertically, as shown in the side view of Fig. 3 and the perspective view of Fig. 4, two transmissive screen units A ₃ and A ₄ are arranged vertically on the same plane. Connect them side by side.

In this case, the projectors L ₃ and L ₄ are adapted to send partial images to their respective screen units A ₃ and A ₄ , respectively.

The transmission screen units A ₃ and A ₄ have a height H, a projection distance P (distance between the projection lenses O ₁₁ and O ₁₃ of the projector and the positions O ₁₂ and O ₁₄ of the transmission screen), and a viewing distance D (transmission (distance between the screen positions O ₁₂ and O ₁₄ and the planned representative position AU of the viewer). The line connecting O ₁₂ and O ₁₄ is the transmission screen unit
The points that intersect with the edges of A ₃ and A ₄ are C ₁₀ , C ₁₁ and C ₁₂ (however, C ₁₀
is the point common to A ₃ and A ₄ ), then C ₁₁ C ₁₀ C ₁₂ is a vertical line X ₁₁ X ₁₂ connecting the centers of the screen. Y ₁₁ Y ₁₂ is a line on the seam of the transmission screen unit, and Z ₁₁ Z ₁₂ passes through C ₁₀ and connects the above X ₁₁ , X ₁₂
and a line perpendicular to Y ₁₁ and Y ₁₂ .

When doing this, the vertical projection angles of O ₁₁ and O ₁₂ are 2β, respectively, and the viewing angle of AU is 2δ, and the angle
Since O ₁₁ C ₁₀ Z ₁₁ = β and the angle O ₁₃ C ₁₀ Z ₁₁ = β, the blind spot space on the projector side is 2β, and AUC ₁₀ Z ₁₂ is the angle δ. Therefore, if the transmissive screen is connected and supported in the blind space using triangular girders Tb having an apex angle of 2β or less, the screen can be supported without visual appeal to the joints of the transmissive screen units.

In addition, as shown in Figure 5, the transmission type screen unit
A ₁ , A ₂ The center of the two images is the location of the representative viewer.
If the center positions of the screen units are arranged on the same arc (radius D) from AU and projected from each projector L ₁ and L ₃ at a projection distance P, then
When the half-angle α of the projection light flux and the half-angle γ of the angle looking into the projection screen, a blind spot of 2(α+γ) is created at the joint of the projection screen units A ₁ and A ₂ on the projector side.
Therefore, a triangular prism Tc with an apex angle of 2(α+γ) or less
can be used in this area to support the screen seam without visually appealing.

In this case, it is of course possible to combine two triangular prisms having an apex angle of α+γ=φ in this part. Although not shown in the drawings, it will be easily understood that if the transmissive screen units are arranged adjacent to each other in the height direction in a similar arrangement, triangular girders may be used.

Next, from the perspective of building materials, 900mm×
1800mm is the upper limit of the standard, so if you make a screen that is 900mm tall and 1800mm wide and add it, its diagonal length will be about 2000mm. When one projection device is used for one screen, the distance between the projection lens and the screen, that is, the projection distance, is generally approximately equal to the diagonal length of the screen, so this is also approximately 2000 mm.

Based on this, the half angle α of the central angle of the projection luminous flux is tan, where W is the width of the screen and P is the projection distance.
α=W/2P.

Therefore, in the above example, since tanα=1800/2×2000, α is approximately 24 degrees.

In the embodiments of the present invention as shown in Figs. 1 and 2 (optical axis parallel), if α = 24 degrees, the blind angle is 48 degrees, and the triangular prism used here has a sufficiently wide angle and is easy to handle. be.

Further, in the embodiment shown in FIG. 5, if α+γ=24 degrees, the angle of the triangular prism is 48 degrees, which is also a sufficiently wide angle.

Further, in carrying out the present invention, a column whose cross section is a right triangle whose apex angle is angle α as shown in FIG. 1, angle β as shown in FIG. 3, and angle α+γ=φ as shown in FIG. Alternatively, it is also possible to use a combination of two girders.

Figure 6-1 is an example of a state in which screens are installed using the present invention, with transmission type screen units A ₁ and A ₂
There is a triangular prism T at the joint part, and a frame-like frame at the other parts.
Fl is fitted. Note that the triangular prism T and the upper and lower frames are connected by a U-shaped connector C.

Note that this assembly example is of course just one example, but the triangular prism or triangular girder used for the blind spot may have its tip rounded, or it may be a triangular prism or triangular girder with an apex angle approximately 1/2 of the blind spot. It is possible to carry out appropriate modifications such as fitting each screen unit into a picture frame using girders and other frames, and later assembling the triangular prisms and triangular girders together.

FIG. 6-2 shows an example of joining the screen and the triangular prism according to the present invention, and is a perspective view when the screens A ₁ and A ₂ are connected by a connecting fitting 13, where 14 is a screw and 15 is a triangular prism. In this case, it is easy to understand that the same thing can be done with a triangular girder instead of a triangular prism. Further, in the illustration, connecting fittings are used, but considering the materials of the screen and pillars, they may be joined using an adhesive with good adhesiveness, such as an anaerobic adhesive.

Next, the state of implementation using the method of the present invention will be described.

Taking the α and β angles in Figures 1 and 3 mentioned above as an example, in the screen unit arrangement with the optical axis parallel, if α or β is 24 degrees, the apex will be 24 degrees x 2 = 48 degrees. Since it is sufficient to use a triangular prism or a triangular girder at the corner, the angle is sufficiently wide.

Furthermore, if the arrangement is on a circular arc surface as shown in FIG. 5, twice the γ angle is added to this, so a triangular prism or triangular girder with a larger apex angle can be used.

Also, the above triangular prism or triangular girder is α or β or α
Enclose each screen unit as a frame with a right triangular cross section having an apex angle of +γ = φ or β + δ = ω,
These picture frames can be assembled to form the entire screen.

Therefore, it is relatively easy to obtain structural materials for the frame with sufficient strength, and it is also possible to construct a large screen that is completely unobtrusive to the audience.

Note that there is generally no need to consider the blind spots 2γ and 2δ on the viewer's side in the crossbeam.
This is because in the case of a large screen, the height is usually smaller than the width.

Next, how can we make the seams of the screen less noticeable in appearance? This can be done by taking into account the limitations of the naked eye in discerning details. That is, the minimum value of the seam that can be discerned by the naked eye is determined by the resolution of the naked eye. That is, since this is 0.00029 in terms of visual angle, it can be found by multiplying this by the distance to the target. An example of this is as follows.

Distance from the naked eye Resolution 250mm 0.07mm 500〃 0.15〃 1000〃 0.3〃 2000〃 0.6〃 5000〃 1.2〃 10000〃 2.4〃 20000〃 5.0 〃 If the width is less than this dimension, it will not be an eyesore at all.

Therefore, in the present invention, the ridgeline of the triangular prism or triangular girder is allowed to be chamfered to the above dimensions.

Note that the dimensions of the triangular prism or triangular girder used in the present invention in the depth direction, that is, the height direction of the isosceles triangular cross section, can be arbitrarily selected, so that a sufficient depth size can be selected to maintain the required strength.

Next, when considering the total width of the integrated projection screen, it is generally considered appropriate to have a width approximately the same as the viewing distance, so an example of this is shown below.

If the unit size projection screen is 1800 mm wide and 10 screens are lined up horizontally to make a total width of 18000 mm, then 5 screens are placed on each side of the center line of the entire screen on the right and left sides. Since it is appropriate to arrange them on the circumference with the radius of the standard viewing distance, in such a case, each screen unit has a corresponding projection device and one screen -
1 projection device. The projection lens and the standard audience are the viewing field lens (Fresnel lens) of the projection screen, and the function of the lenticular lens is that each image point formed by the projection lens becomes a secondary light source. The distribution is dispersed according to the .

This effect occurs over the entire surface of the projection screen, and as a result, the audience located within the designed range is located within the distribution angle of the projection light flux, and therefore cannot receive the projection light flux from either direction from the entire surface of the projection screen. This is possible.

Therefore, the audience can see an evenly bright screen. FIG. 7 is an intensity vector diagram of the angular distribution of the dispersed light beam at each image point of the lenticular lens, and in one example, the maximum distribution angle range is 60° or more left and right.

In the figure, the length scale of the vector is the logarithm of the relative value of transmittance, and this can be said to represent the brightness perceived by the audience according to Lambert Beer's sensory law.

The projection lens and the audience are in a conjugate relationship with each other through the viewing lens (Fresnel lens) of the screen. In other words, the standard audience will face all the unit screens. At the same time, the projection light beam is distributed to the left and right by the directional lenticular lens of the transmissive screen in an approximately average distribution.

The directivity of modern and improved transmissive screens is extremely wide, with some reaching up to 60 degrees left and right (Figure 7). Therefore, the directional characteristics of the unit screen are also associated with the overall large screen, and are designed to provide a large screen with high average brightness, high quality, and a rich sense of reality to a large number of spectators distributed over a wide range centering on the standard audience. can be provided.

The total luminous flux from the projection optical system is not emitted outside the designed range. Therefore, if these are integrated with the utmost care, a large screen capable of projecting a large projection screen with an average luminous intensity distribution with little unevenness can be produced as required.

Furthermore, compared to the large size of the screen, the space occupied behind the screen, which is a disadvantage of a transmissive screen, can be reduced in depth. In other words, since the space occupied is the projection distance of the unit projection system, it is clear that in the case of a huge screen, this results in a great space saving.

Note that when implementing the present invention, the screen is used as the fifth screen.
Of course, it is also possible to have an arrangement that is closer to a flat surface than the arcuate surface with the curvature shown in the figure.

(Effects of the Invention) According to the present invention, triangular prisms and/or triangular girders are used in the blind areas of the joints of the transmissive screen units, and the whole is assembled with push edges, and the screen joints are not seen at all from the viewer's side, so the frame is This makes it very easy to view the frame without causing the fatigue caused by looking at the frame, and it becomes possible to perform projection measures while exchanging emotions with the audience, and it is also possible to show fast-moving images using a cinematic method.

[Brief explanation of drawings]

Fig. 1 is a top view of one embodiment of the present invention in which the screen units are arranged in a straight line in the horizontal direction, Fig. 2 is a perspective view of the same, and Fig. 3 is another embodiment of the present invention in which the screen units are arranged in a straight line. FIG. 4 is a side view of the screens arranged in a straight line in the vertical direction, FIG. 4 is a perspective view, and FIG. FIG. 6-1 is a top view of screen units arranged horizontally, FIG. 6-1 is a perspective view showing an example of a state in which screens are installed using the present invention, and FIG. FIG. 3 is a cross-sectional view when connected. FIG. 7 is an intensity vector diagram of the angular distribution of the dispersed light beam at each image point of the lenticular lens, FIG. 8 is a side view of a single lens, and FIG. 9 is a side view of a two lens. A ₁ , A ₂ , A ₃ , A ₄ ... Transmissive screen unit,
W... Width, H... Height, P... Projection distance, D...
Viewing distance, L ₁ , L ₂ , L ₃ , L ₄ ... Projector, O ₁ ,
O ₃ , O ₁₁ , O ₁₃ ...projection lens, O ₂ , O ₄ , O ₁₂ ,
O ₁₄ ... Center position of the transparent screen unit,
TaTcT...triangular prism, Tb...triangular digit, α...half angle of the horizontal center angle of the projection light beam, β...half angle of the vertical center angle of the projection light beam, γ...half angle of the angle looking into the unit projection screen (horizontal), δ...half-width of the angle looking into the unit projection screen (vertical), F...image point, 1
1b...Fresnel lens sheet, 12b...lenticular lens sheet.

Claims (1)

[Claims] 1. A single large-screen screen is formed by arranging a plurality of transmission screen units adjacent to each other on the same plane or curved surface of the same circular arc so that there are vertical and/or horizontal joints. A large screen characterized in that a triangular prism or triangular girder having an apex angle equal to or less than the blind spot is provided close to the screen in the blind spot of the light rays incident on each screen unit, and the screen is supported by this. Construction method 2 of a transmission screen for use When multiple projection screens are arranged on the same plane and the horizontal blind spot of the incident light beam is α and the vertical blind spot is β, a triangular prism with an apex angle of 2α or less and/or a triangular prism with an apex angle of 2β or less Method 3 of constructing a large-screen transmissive screen according to claim 1, characterized in that the triangular girder is used in the blind spot on the projection side of the projection screen to support the projection screen.3 A plurality of projection screens is placed on a certain circular arc surface with the center axis at the central audience position, the vertical half angle of the central angle of the incident light beam is α, the horizontal one is β, and the central angle looking into the projection screen is When the horizontal half-width is γ and the vertical half-width is δ, projection is performed using triangular prisms and triangular girders whose apex angles are equal to or less than the double angle of α + γ = φ and β + δ = ω, respectively, in the blind spot on the projection side of the projection screen. A method of constructing a transmission type screen for a large screen according to claim 1, characterized in that the screen is supported.