Illuminated sign using inlaid transparent flat plate

Abstract

To solve the problem in which: an "illuminated sign using an inlaid transparent flat plate" formed by putting a transparent flat plate in the shape of a character diagram (protrusion transparent flat plate) into a recess provided in a transparent flat plate in a predetermined size (recess transparent flat plate) includes various characteristics such as a special effect of floating illuminated characters and diagrams in a space, an ability to deal with fine character diagrams such as Chinese characters, which have been difficult to be dealt with, and its reduced weight and thickness; however, in actually building the illuminated sign, there are problems such as preventing light leakage, achieving uniform brightness on a display surface, and simplifying methods for manufacturing and joining respective members.SOLUTION: The problems are solved by adopting, as a light source, a LED light source employing an "inverse placement double diffusion system" for causing a reflecting plate serving also as a bottom plate to reflect light, providing a side plate on a bottom face of a protrusion transparent flat plate along a welded portion, providing a partition plate at a portion proximate to the LED light source, and changing widths of the side plate and the partition wall as necessary.SELECTED DRAWING: Figure 13

Description

[Technical field]

[0001] The illuminated sign shown in Patent Document 1, Figure 10, is constructed by inlaying two transparent flat plates. -Special effects that make illuminated letters and figures appear to float in space, - Support for detailed character patterns, such as Chinese characters, which were previously difficult to handle, -Thin and lightweight, The aim is to create an illuminated sign that has the above-mentioned characteristics and can be easily produced using only commonly available laser processing machines, and the present invention provides a specific means for constructing such an illuminated sign. [Patent Document 1] Patent Publication No. 2012-226064 [Background technology]

[0002] The illuminated sign described in Patent Document 1, as shown in FIG. 1, is constructed by fitting a transparent flat plate (convex transparent flat plate 1b) shaped like a letter pattern into a transparent flat plate of a predetermined size (concave transparent flat plate 1a) with a concave portion of the same shape as the convex transparent flat plate 1b, and is a type of inlay.

[0003] The light source 1c is provided in the recess of the recessed transparent flat plate 1a, has the same shape as the protruding transparent flat plate 1b, is attached to the surface of the protruding transparent flat plate 1b, and is designed to illuminate a top plate 1d having a light diffusion effect. In this case, the surface 1e and cross section 1f of the concave transparent flat plate 1a, and the cross section 1g and back surface 1h of the convex transparent flat plate 1b are perpendicular to each other, so that the surface 1e of the concave transparent flat plate 1a and the cross section 1g of the convex transparent flat plate act as a light-shielding surface for the light source 1c toward the outside forward due to the total reflection effect of light (Patent Document 1, paragraphs

[0012] to

[0014] ). Hereafter, illuminated signs with this structure will be referred to as "illuminated signs made of inlaid clear plates" or "ICP (Inlaid Clear Plates) illuminated signs."

[0004] As mentioned earlier, one of the features of ICP illuminated signs is that all of the materials can be produced using a laser processing machine that can cut and process flat acrylic sheets of about 10 mm in thickness, a type of machine that is widely used in the sign and sign industry. FIG. 2 shows an example of a concave transparent flat plate 2a, a convex transparent flat plate 2b, and a top plate 2c that constitute an ICP illuminated sign.

[0005] When a convex transparent flat plate 1b with a thickness of about 10 mm is inlaid into a concave transparent flat plate 1a and a light source 1c is installed in the concave of the concave transparent flat plate 1b, the distance between the light source 1c and the top plate 1d cannot exceed about 20 mm. This means that the light source 1c and the top plate 1d must be much closer than in a general illuminated sign (Patent Document 2, Figure 1), making it difficult to ensure a sufficient light diffusion space (Patent Document 2, paragraph

[0010] ). For this reason, in Patent Document 1, paragraph

[0007] , the "inverted double diffusion method" is used as the light source for ICP illuminated signs (Patent Document 3, paragraph

[0006] ,

[0007] ) LED light sources are proposed. [Patent Document 2] Patent No. 5685790 [Patent Document 3] Patent Publication No. 2013-68756

[0006] The LED light source 1c, which uses the "inverted double diffusion method," is a light source in which the optical axis of the LED that serves as the light source is directed toward the bottom plate 1i that also serves as a reflector, and the light from the LED is reflected and diffused by the bottom plate 1i before illuminating the top plate 1d.This mechanism makes it possible to realize a thinner illuminated sign.

[0007] The installation method for the inverted LEDs that make up the "inverted double diffusion method" is as follows: Examples include a strip-shaped backlight shown in FIG. 4 of Patent Document 3, paragraph “0011”, an inverted LED lamp shown in FIG. 7 of Patent Document 3, paragraphs “0017” and “0018”, and a method using a transparent resin plate shown in FIG. 13 of Patent Document 2, paragraph “0061”.

[0008] As for the means for reflecting and diffusing the light of the inverted LED, as shown in Patent Document 2, paragraph “0052”, there is a method of using a white acrylic plate or a semi-transparent milky acrylic plate as a base plate that has both reflection and diffusion effects, or a method of using a composite material made by bonding a white milky semi-acrylic plate to a mirror surface or a white reflective material. Hereinafter, these various LED installation methods, as well as the reflection and diffusion of LED light, will be collectively referred to as the "inverted double diffusion method," which refers to the LED backlight method in which the LED light, with its optical axis facing away from the tabletop, is reflected and diffused in the direction of the tabletop.

[0009] In addition, IPC illuminated signs that use inverted double diffusion type LEDs as their light source will be referred to simply as IPC illuminated signs for short. DISCLOSURE OF THEINVENTION [Problem to be solved by the invention]

[0010] The present invention is intended to solve the following problems that arise when actually constructing the above-mentioned ICP illuminated sign.

[0011] "Challenge 1" As mentioned above, the ICP illuminated sign shown in Figure 1 is constructed on the premise that the cross section 1g of the convex transparent flat plate and the surface 1e of the concave transparent flat plate function as shading surfaces for light from the light source 1c provided in the recess of the concave transparent flat plate 1a.

[0012] To actually construct an ICP illuminated sign, the convex transparent flat plate 3b and the concave transparent flat plate 3a must be welded and fixed with an acrylic adhesive or the like, as shown in Figure 3. At this point, the welded surface 3c no longer functions as a light reflecting surface, and all light incident on the welded surface 3c passes through this surface. In other words, light from the light source housed in the concave of the concave transparent flat plate 3a that passes through the welded surface 3c passes through the two light-shielding surfaces (Figure 1, surface 1e, cross section 1g), and these surfaces lose some of their function as light-shielding surfaces.

[0013] "Challenge 2" In addition, in FIG. 1, no light blocking effect is produced for light that passes through cross section 1f from light source 1c provided in the recess of recessed transparent flat plate 1a and travels toward side surface 1j, and the light from light source 1c leaks out from side surface 1j to the outside. For example, if this illuminated sign is attached to a wall, the leaking light can unintentionally illuminate the wall around the sides of the sign, causing a design problem.

[0014] "Challenge 3" 1, it is desirable for the concave cross section 1f of the concave transparent flat plate 1a to reflect as much light from the light source 1c as possible in order to improve the illuminance of the top plate 1d. However, most of the light passes through this cross section 1f, and the cross section 1f hardly functions as a light reflecting surface.

[0015] "Challenge 4" As with other illuminated signs, an important design issue for ICP illuminated signs is to keep the brightness of the top plate as uniform as possible. For this reason, it is required that the LED light sources be arranged so that the distance between each LED is as uniform as possible. Since ICP illuminated signs are illuminated signs capable of displaying highly detailed character patterns, the LED arrangement tends to be complex, making it even more important to maintain uniform brightness. In particular, when the strip-shaped backlight method is adopted, there is a restriction on placement that the LEDs must be placed at regular intervals on a continuous tape, and it may be necessary to place two LED light sources 4e, 4d close to each other as shown in FIG. 4. The brightness of the top plate 4c near the two closely arranged LEDs 4e, 4d becomes significantly higher than that of the surrounding area, resulting in brightness spots, which is an obstacle in terms of design. [Means for solving the problem]

[0016] The solution to "Problem 1" where the LED light source penetrates the welded surface is as follows:

[0017] The hatched portion in Fig. 5 indicates the range of the light beam passing through the welding surface 5c in the convex transparent flat plate 5b and the concave transparent flat plate 5a that are welded to each other. As shown in the figure, when the concave transparent flat plate 5a and the convex transparent flat plate 5b are directly welded, to block the light passing through the welding surface 5c, either the light transmission surface 5d of the concave transparent flat plate 5a or the transmission surface 5e of the convex transparent flat plate 5b may be shaded. In this solution, as described below, considering the advantage of also serving as a solution to other problems, a side plate 5g with a width t equal to or greater than the width e of the light transmission surface 5e is provided along the concave inner cross-section 5f on the bottom surface 5h of the convex transparent flat plate 5b, and the light transmission surface 5e is shaded to perform a light shielding function.

[0018] Note that since the side plate 5g also has a negative effect of casting a shadow on the top plate, its thickness t is preferably made as thin as possible. When the refractive index of the convex transparent flat plate 5b and the concave transparent flat plate 5a is n and the width of the welding surface 5c is d, the width of the light transmission surface 5d on the surface of the concave transparent flat plate 5a is equal to the width of the light transmission surface 5e on the back surface of the convex transparent flat plate 5b. If the width is e, according to the principle of refractive index, θ = sin -1 (1 / n) and e = d(tanθ) results. In the case of acrylic or the like, generally θ < 45°, and therefore e < d, and the width e of the light transmission surface 5e is smaller than the width d of the welding surface 5c. Therefore, (since the width e of the light transmission surface is smaller than the width d of the welding surface), if the width t of the side plate 5g is equal to the width d of the welding surface, the light shielding function can be achieved.

[0019] Also, the side plate 5g has the effect of also shading the concave inner cross-section 5f of the concave transparent flat plate 5a, and also serves as a solution to "Problem 2". Furthermore, if a white acrylic material or the like is used as the material of the side plate, the reflection function can also be improved. That is, it is convenient because "Problem 3" can be solved simultaneously.

[0020] The solution described above is based on the premise that the concave transparent flat plate 5a and the convex transparent flat plate 5b are directly welded to each other (hereinafter, this solution will be referred to as the "direct welding method"). Next, we will describe a solution in which the welded surface itself is light-shielded. That is, in the solution described below (called the "light shielding band method"), as shown in FIG. 6, the concave transparent flat plate 6a and the convex transparent flat plate 6b are fused via a light shielding band 6c (for example, black acrylic material).

[0021] In this "light shielding band method," light passing through both the concave transparent flat plate 6a and the convex transparent flat plate 6b at the same time is completely blocked by the light shielding band 6c. However, the welded portion 5d between the convex transparent flat plate 6b and the light-shielding band 6c is thought to be filled with shapeless transparent acrylic particles that have melted, condensed, and solidified, and it is therefore not possible to optically completely seal this gap. Therefore, it is not possible to block light passing through this welded portion 6d, and light from the light source leaks through the welded portion between the convex transparent flat plate 6b and the light-shielding band 6c, which is an obstacle to the design.

[0022] To prevent this light leakage, as in the case of the "direct welding method" described above, it is effective to provide a side plate 6e to close the gap of the welded portion 6d of the convex transparent flat plate 6b as shown in FIG. The width of the side panel 6e required to close the gap in the welded portion 6d is not a problem as long as it is equal to or greater than the gap width. However, the width of the side panel 6e is subject to the constraint that "it must be greater than or equal to the width that can be stably cut out by a leather processing machine," as described below.

[0023] The light-shielding band 6c and the side plate 6e also have the effect of shading the inner cross section 6f of the recess, and thus also provide a solution to "problem 2", as in the "direct welding method". Furthermore, in the case of the "shade band method," a material with poor light reflecting function, such as black acrylic, is used for the shade band 6c, but by using a white acrylic or the like for the material of the side panel 6e, the reflecting function can be improved and "Problem 3" can be solved at the same time, just like in the "direct welding method."

[0024] In addition, when the concave transparent flat plate and the convex transparent flat plate are bonded together via a light-shielding band, the light-emitting display part that represents characters and figures will have the light-shielding band surrounding the periphery of the convex transparent flat plate. The design problem caused by this can be avoided by making the width of the light-shielding band as small as possible.

[0025] Hereinafter, an IPC illuminated sign in which a side panel is provided along the welded portion at the bottom of the convex transparent flat plate shown in the "direct welding method" or "shading band method" will be referred to as an IPC illuminated sign with a side panel method.

[0026] As described above, the side panel method prevents light leakage from the welded parts of the convex transparent flat plate in IPC illuminated signs, improves the light reflection function at the cross section of the concave transparent flat plate, and prevents light leakage. On the other hand, the side panel method creates new problems, as described below.

[0027] As shown in Figure 7, in order for an inverted double diffusion type LED light source 7a to obtain sufficient illuminance on the tabletop, it is necessary to ensure a sufficiently wide LED light reflection area 7c and opening 7d in the reflector 7b. However, as shown in Figure 8, the installation of a side panel 8j narrows the light source opening 8g and reflection area 8f by the thickness of the side panel.

[0028] This results in insufficient reflected light, which reduces the illuminance on the tabletop.

[0029] To solve these problems, the side panels need to be made as thin as possible. However, the band-shaped side panels, which must have a complex shape to accommodate the characters and patterns to be displayed, cannot be made too thin; if the acrylic or other material is used, it will distort and deform due to heat during the laser cutting process, making it impossible to obtain the required precision. In other words, the thickness of the side panel is restricted to a thickness that can be cut out continuously and stably by laser processing.

[0030] A solution to the problem posed by this constraint is to vary the thickness of the side panels as needed. That is, although it is not possible to cut out a continuously thin, strip-like side panel with leather processing, it is possible to make up to some extent for the lack of strength by thinning only the necessary parts and making the other parts thicker.

[0031] Figures 9 and 10 show the relationship between the LED light source and the thickness of the side panel in the narrow area of ​​the top panel. In order to ensure the necessary reflective area 9f and opening on the reflector 9i around the LED light sources 9c, 10c, the side plates 9j, 10j are made thin, and in areas away from the LED light sources 9c, 10c that do not contribute much to reflected light, the side plates 9j, 10j are made thick to ensure the necessary opening and reflective area (see examples).

[0032] The side panel method also provides a solution to the aforementioned "problem 4." As mentioned above, in an inverted double diffusion type LED light source, the reflected light can be attenuated by narrowing the reflection area and opening of each LED. 11 shows an example of a partition plate 11r that is provided to narrow the reflection areas and openings of two LED light sources 11p, 11q that are too close to each other, thereby attenuating the reflected light. The height of the partition plate 11r is the same as that of the side plate 11j, and it can be cut out by laser processing at the same time as part of the side plate 11j, and the attenuation of the reflected light can be controlled by the thickness of the partition plate 11r. Effect of the Invention

[0033] The IPC illuminated sign, which has a built-in inverted double diffusion light source and is constructed by inlaying a convex transparent flat plate into a concave transparent flat plate, is an innovative illuminated sign with excellent features, as described in paragraph "0001". However, there are several challenges to overcome in its production, such as preventing light leakage, dealing with brightness unevenness, and methods of joining the components. The present invention solves these problems while maintaining the innovative characteristics of IPC illuminated signs, and provides a practical means for easily producing IPC illuminated signs using only commonly used leather processing machines. EXAMPLES

[0034] The embodiment described below is an IPC illuminated sign using the side panel method ("direct welding method" or "shading band method") that uses an "f"-shaped top panel 2b and a convex transparent flat panel 2c as shown in Figure 2, and uses a band-shaped backlight as the light source.

[0035] In an IPC illuminated sign using a side panel system with a strip backlight, the side panels must be set at a height that allows space to accommodate the strip backlight; in this embodiment, this is set to 5 mm.

[0036] With a leather processing machine, the width that can be cut out continuously and stably without distortion from a 5mm high side panel is usually about 2mm. Figure 12 shows the arrangement of side panels and strip backlights in an IPC illuminated sign using a side panel system with strip backlights, assuming that the convex transparent flat panel 2b and top panel 2c of Figure 2 are used and that the side panels are 5 mm high and have a uniform width of 2 mm. As shown in the figure (Figure 12), in this example of an IPC illuminated sign, the side panel width is uniform (2 mm), so the width of the convex transparent flat panel is narrow, resulting in locations 12d where a sufficient reflective area and opening for the LED light source cannot be secured, and there is also location 12e where two LED light sources are installed close to each other, causing luminance spots on the top panel around them, meaning there are locations where uniform luminance is not maintained.

[0037] As described above in the "Means for Solving the Problems" section, this embodiment solves the above problem by varying the side plate width. That is, in this embodiment, as shown in FIG. 13, in the narrow portion 13d of the convex transparent flat plate (top plate), the side plate 13b is thinned (1 mm) around the LED light source to ensure a reflective area and an opening, and the side plate 13b is thickened (2 mm) away from the LED light source to ensure the strength of the side plate.

[0038] Furthermore, at a location 13e where the two LED light sources are close to each other, a partition plate 13f is added to the side plate to narrow the opening and reflection area of ​​the LED light source, thereby preventing luminance unevenness on the tabletop.

[0039] In this embodiment, the transparent flat plate of the convex portion and the transparent flat plate of the concave portion are welded by the "direct welding method" or "light shielding band method" described above. When welding is performed by the "direct welding method" (FIG. 5), since the minimum width of the side plate is 1 mm, the welding portion 5c of the convex transparent flat plate is set to the same length of 1 mm (see paragraph "0018"). The thickness of the top plate is 2 mm to take into account the light diffusion effect, the thickness of the convex transparent flat plate 5b is 10 mm to ensure the space between the top plate and the reflector and obtain the light diffusion effect, and the thickness of the concave transparent flat plate 5a is set to a thickness (6 mm) sufficient to cover the above-mentioned welded portion and side plate.

[0040] When the convex transparent flat plate and the concave transparent flat plate are welded using the "light-shielding band method" (Figure 6), the welded portion 6d of the convex transparent flat plate is welded via the light-shielding band 6c, so there are no optical constraints on the length of the welded portion, and in this embodiment, it is set to 2 mm, which ensures a welding surface wide enough in terms of strength. There are no optical restrictions on the thickness of the concave transparent flat plate 6a, and in order to maintain the strength as a support plate, the thickness of the concave transparent flat plate is set to 5 mm or 3 mm. The height of the light-shielding band 6c is set to 7 mm, which is the height sufficient to cover the welded portion 6d and the side plate 6e. The top plate, the convex transparent flat plate, the side plates, and the strip-shaped backlight are constructed in the same way as the "direct welding method."

[0041] As described above, the difference between the "direct welding method" and the "light-shielding band method" lies in the length of the welded part of the convex transparent flat plate (1 mm and 2 mm respectively) and the required thickness of the concave transparent flat plate. In other words, although the "shade band method" requires an extra component called the shade band, Compared to the "direct welding method," this has the advantage that the welded part is stronger and a thinner recessed transparent flat plate can be used. [Brief description of the drawings]

[0042] [Figure 1] Cross-section of an illuminated sign made of inlaid transparent panels [Diagram 2] Examples of concave transparent flat plate, convex transparent flat plate, and top plate [Diagram 3] Welding part of concave transparent plate and convex transparent plate [Figure 4] Closely spaced LED light sources [Diagram 5] Direct welding method [Figure 6] Shading band method [Figure 7] Reflective Areas and Apertures [Figure 8] Side panel type reflection area and aperture [Figure 9] Side panel shape to ensure reflection area and opening (3D diagram) [Figure 10] Side panel shape to ensure reflection area and opening (plan view) [Figure 11] Partition plate between adjacent LED light sources [Figure 12] Example of side plate system with uniform thickness side plates [Figure 13] Example of side plate system according to the present invention [Explanation of symbols]

[0043] 1a Recessed transparent plate 1b: Convex transparent plate 1c...LED light source 1d...Tabletop 1e: Recessed transparent plate surface 1f: Cross section of recess in transparent flat plate 1h Back side of the convex transparent plate 1i...Reflector plate (bottom plate) 1j Side of concave transparent plate 2a Recessed transparent plate 2b: Convex transparent plate 2c...Tabletop 3a Recessed transparent plate 3b... Convex transparent flat plate 3c····Welding area 3f····Concave section of transparent flat plate 3h··· Inside the convex transparent plate 4a····Concave transparent plate 4b····Convex transparent flat plate 4c····Top board 4d····LED light source 4e····LED light source 5a···· Concave transparent plate 5b····Convex transparent flat plate 5c····Welding area 5d····Concave transparent flat surface light transmission surface 5e····Light-transmitting surface inside the convex transparent flat plate 5f····Concave section of transparent flat plate 5g····Side panel 5h····The inside of the convex transparent plate 6a····Concave transparent plate 6c····LED light source 6f····Concave section of transparent flat plate 6i····Reflector 7a····LED light source 7b····Reflector 7c····Reflection field 7d····Opening 8c····LED light source 8j····Side panel 8i····Reflector 8f····Reflection field 8g····Opening 9c····LED light source 9f····Reflection field 9i····Reflector 9j····Side panel 10c···LED light source 10j···Side panel 11b···Convex transparent flat plate 11c···Top plate 11i···Reflector 11j···Side panel 11p···LED light source 11q···LED light source 11r Partition plate 12b...Side plate 12c...LED light source 12d: Reflection area, areas where open space is not secured 12e Where LED light sources are installed close together 13b...Side plate 13c...LED light source 13d: The part where the side panel width is narrowed 13e Where LED light sources are installed close together 13f Partition plate

Claims

1. This illuminated sign is composed of a convex transparent flat plate shaped like letters and a concave transparent flat plate with a concave portion into which the convex transparent flat plate is fitted and fixed, and has the following features:

1. An inverted double diffusion type LED light source is used, in which the light from the LED is reflected and diffused by a reflector that also serves as the base plate.

2. The above-mentioned convex transparent flat plate is fitted directly into the concave portion of the above-mentioned concave transparent flat plate or through a light-shielding band, and then fixed by welding.

3. A side plate is provided on the bottom surface of the convex transparent flat plate along the welded portion to block the LED light that passes through the welded portion.

2. An illuminated sign as described in claim 1, in which the thickness of the side panels is made thinner near the LED light source to ensure a wide reflective area and opening on the reflector, and the strength of the side panels is ensured by making the side panels thicker in areas away from the LED light source.

3. An illuminated sign as described in claim 1, further comprising partition plates between a number of closely spaced LED light sources, thereby limiting the reflective area on the reflector of those LED light sources and the width of the opening, thereby reducing brightness unevenness.

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