US 3780463 A
A dsiplay particularly adaptable for displaying a message comprising a light-carrying body and a source of light disposed along at least one edge of the body is disclosed. The message is placed in intimate contact with one surface of the light-carrying body. A contrasting backing material is disposed about and/or behind the message and is held in remote contact with the body. The edges of the body adjacent to the sources of light are shaped such that the edges are relatively normal to the incident light rays, thus allowing most of the light to refract through, thus easily entering the body.
Description (OCR text may contain errors)
Aronoff ILLUMINATED DISPLAYS AND ILLUMINARIES  Inventor: Leonard S. Aronoff, 16751 Tupper St., Sepulveda, Calif. 91343  Filed: May 15, 1972  Appl. No.: 253,323
Related U.S. Application Data  Continuation-impart of Ser. No. 855,197, Sept. 4,
 U.S. C1. 40/130 K  Int. Cl. G02b 5/14  Field of Search 40/130 K, 130 R  References Cited UNITED STATES PATENTS 3,349,511 10/1967 Aronoff 40/130 K 2,623,313 12/1952 Fuchs..... 3,497,686 2/1970 Young 40/130 K 1 Dec. 25, 1973  ABSTRACT A display particularly adaptable for displaying a message comprising a light-carrying body and a source of light disposed along at least one edge of the body is disclosed. The message is placed in intimate contact with one surface of the light-carrying body. A contrasting backing material is disposed about and/or behind the message and is held in remote contact with the body. The edges of the body adjacent to the sources of light are shaped such that the edges are relatively normal to the incident light rays, thus allowing most of the light to refract through, thus easily entering the body.
9 Claims, 23 Drawing Figures PATENTEDUEEZSIQB SHEETBUFS LJLI ILLUMINATED DISPLAYS AND ILLUMINARIES This is a continuation-in-part of Ser. No. 855,197 filed on Sept. 4, 1969 now abandoned.
BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to lighted signs, displays, luminaries and similar devices.
2. Prior Art The prior art in edge lighted devices provides no information or explanation of the new phenomenon described herein with the consequent results that none of the prior devices attain the qualities and performance produced by this invention. All of the devices in the prior art lack some of the essential components that are necessary for an effective illuminated display. In order to produce the desired qualities and performance, this invention utilizes a combination of components, and their relative application, to optimally produce the desired improvements. Among these are:
l. A proper light transmitting body whose critical angle of reflection is known and utilized;
2. Adequate materials for the message and their proper application to the light transmitting body, described as intimate contact;
3. Adequate background or backing material and its proper application to the light-carrying material to produce an optimum contrast with the message;
4. Proper treatment of the edges of the light transmitting body for optimum efficiency and uniformity;
5. Proper filtering materials and method of application thereof for specific effects; and
6. The proper application of the light source with reference to the message, background material and the edges of the light transmitting body.
In my previous US. Pat. No. 3,349,51 l the concept of intimate contact is briefly, though inadequately, defined and discussed. This concept is amplified and its necessary relationship to the background material is emphasized in this patent. Furthermore, the method of treatment of the edges, the dispositions of light source with reference to the light-carrying body, and their interrelationships with the background material is utilized in a novel way to produce an improved display.
SUMMARY OF THE INVENTION An illuminated display adaptable for displaying a message or pattern is described comprising a lightcarrying body, a source of light disposed about at least one edge of the body, a message or pattern which is in intimate contact with a surface of the body, and a backing material which is held in remote contact with the surface of the body containing the message. The edges of the body, adjacent to the sources of light are configured such that the light incident on these edges is relatively normal to the edges. This allows substantially all the light from the source, incident on the edge, to enter the body rather than be reflected away from the body.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. la illustrates a plan view of a light-carrying body and source of light and the path of light rays from the source into the body;
FIG. 1b is a plan cross section view through section line la- 1a of FIG. la;
FIG. 2 is a graph illustrating the intensity of illumination reflected from the display material or backing material in the direction of the viewer as a function of the pressure applied to the display material and as a function of the distance maintained between a backing material and the surface of the body;
FIG. 3 is a perspective view of a display comprising a light-carrying body and sources of light;
FIG. 4 is a plan cross section view of the display of .FIG. 3 taken through section lines 4'4 of FIG. 3;
FIG. 5 is a plan cross section view illustrating an alternate embodiment of a display;
FIG. 6 is a plan view illustrating a section of a light carrying body and a source of light partially enclosed within a window defined by an edge of the body;
FIG. 7 is a plan side view of the source of light and light-carrying body of FIG. 6;
FIG. 8 is a plan view illustrating a partial section of a light-carrying body, a source of light enclosed within a reflector and a window defined by one edge of the body;
FIG. 9 is an alternate embodiment of the present invention wherein the sources of light for a display are contained within cavities defined by a light-carrying body;
FIG. 10 is a plan cross section view of the display of FIG. 9 taken through section lines 1010' of FIG. 9;
FIG. 11 is an alternate embodiment of the present invention comprising a tapered light-carrying body;
FIG. 12 is a plan cross section view of the display of FIG. 11 taken through section line l212 of FIG. 11;
FIG. 13 is a plan view of an alternate embodiment of the present invention wherein a border is illustrated around the periphery of a message;
FIG. 14 is a plan cross section view of the display of FIG. 13 taken through section lines 14l4' of FIG. 13;
FIG. 15 illustrates still another embodiment of the present invention wherein a halo effect is produced about a message ABC" and where a bright border is displayed about a dark message XYZ;"
FIG. 16 is a plan cross section view of the display of FIG. 15 taken through section lines l6-16' of FIG. 15;
FIG. 17 illustrates a plurality of displays being illumi nated by a single source of light;
FIG. 18 illustrates an embodiment of the present invention wherein a curved light-carrying body is illustrated;
FIG. 19 is a plan view of a plurality of panels displayingpatterns illuminated by a single source of light;
FIG. 20 is a cross section view of the display of FIG. 19 taken through section lines 20'-20 of FIG. 19;
FIG. 21 illustrates an elongated light source utilized to illuminate a plurality of panels; and
FIG. 22 illustrates an alternate embodiment of a message which may be utilized on the various displays described herein.
DETAILED DESCRIPTION OF THE INVENTION For a better understanding of some aspects of the present invention and for an understanding of the terms intimate contact" and remote contact as used herein, it will be helpful to discuss certain phenomena described in conjunction with FIGS. la and 1b and 2. In FIG. la, a plan view of a light-carrying body, panel 2, is illustrated along with a source of light, bulb 6. Panel 2 may be any light-carrying member such as a plastic or glass member having a generally rectangular shape while the source of light illustrated as bulb 6 may be any known source of light. In the manufacturing of an illuminated display, particularly one utilizing edge light, it is desirous to confine the light flux with the light-carrying body such as panel 2, and to direct the light from the body only at desired areas; for example, the light should be reflected from those areas which define a message and subsequently, refracted out of the body to the viewer. In FIG. In, two light beams emitted from bulb 6 are illustrated within body 2. The outer edges of panel 2 are assumed to be polished edges whose normals are indicated by lines 9. (Note the angle of refraction associated with the light rays transmitted into the panel 2 has not been indicated in order to simplify the diagram.) The angle of incidence between light rays 5 and the edges of panel 2 is a. The critical angle is defined as the angle whose sine is equal to the relative refractive index of the material comprising panel 2 and the material disposed about panel 2, typically, air. For a light-carrying body of glass or plastic, the critical angle is approximately 42 degrees. By properly placing the bulb 6 relative to the panel 2, it is possible to have most of the light flux from the source enter the panel 2 and be contained within the panel.
It has been found that optimum results are achieved where the edges of the light-carrying body are selectively covered with diffusely reflective material in intimate contact with certain portions of the edges. In the presently preferred embodiment, referring to FIG. la, after the edges have been highly polished, the diffusely reflective material is applied to those edges where the angle a is less than the critical angle for the material comprising the light-carrying body such as shown by the light ray 5 which is striking the upper edge of panel 2. For those portions of the edges where the critical angle a is greater than the critical angle for the material such as shown by the light ray 5 which is striking the lower edge of panel 2, no diffusely deflective material is placed along the edges. This results in the optimum conditions for containing light within the body since the polished edges where they may be used, are much more efficient than those portions of the edges which require the reflective material. Additionally, the edges of the light-carrying body should be as perpendicular as possible to the major surfaces of the body.
It is also desirous in the construction of an edge lighted display to have all the light from the source of light striking the edge of the light-carrying body to enter the body rather than being reflected away from the body. In order for this to occur, the angle of incidence of the light with the body must be less than the critical angle for the material comprising the body. In FIG. 1a, the normals to the edge of the body adjacent to bulb 6 are lines 9. If the angle B, the angle of incidence of rays 5 with panel 2, is less than the critical angle, the rays 5 will enter panel 2 rather than being reflected away from the panel. As will later be shown, the recognition of this phenomenon permits the design of an edge of the light-carrying body which is more efficient than a straight edge.
In FIG. 1b, panel 2 is illustrated having a viewing surface 3 and a rear surface 8. A backing plate 4 is illustrated against surface 8 of panel 2. Plate 4 may be any opaque material which is diffusely reflective. That is, material which does not transmit light but rather diffusely reflects the light which is incident upon it. A cover 7 is illustrated covering the plate 4. The covering is utilized for purposes of demonstrating certain phenomena, and serves the function of preventing ambient light from striking plate 4.
Referring to FIG. 2, the abscissa 15 represents in one case the distance d between plate 4 and surface 8 of panel 2 and in another case, the pressure p (force for unit area) which is applied to the plate 4 while the plate is in contact with surface 8 of panel 2. The ordinate 10 of the graph represents the light intensity L" as seen from viewing surface 3.
Curve 14 illustrates the effect of applying pressure on plate 4, on the intensity of light L. It is readily apparent from curve 14 that as pressure is applied to backing plate 4, the intensity of light increases, until the intensity reaches a level 16 after which an increase in pressure 2 has little or no effect on the intensity L. The region in which an increase in pressure on plate 4 does not change the intensity of light L is defined herein as the region of intimate contact. In this region, the plate 4 is in intimate contact with surface 8. When this intimate contact is achieved, most of the light contained within panel 2, which strikes surface 8 is diffusely reflected from surface 8 and is then seen from the viewing surface 3. The conditions of intimate contact may be achieved with or without the presence of cover 7 on panel 2.
The condition of intimate contact which results in the optimum reflectance from surface 8 may be achieved by a number of methods. Where sheets or strips of diffusely reflective material are utilized, as plate 4, the intimate contact can be achieved by applying pressure directly to the sheets or strips. The surface 8 should be absolutely clean and devoid of any film before a strip or sheet is placed in intimate contact with the surface 8. Also, care should be taken to avoid having any films or air pockets between the sheets or strips and the surface. The condition of intimate contact may also be achieved by silk-screening or similar processes wherein suitable opaque diffusely reflective paints are used. The condition may also be achieved by applying suitable paints to the surface 8 under a forced spray or by a vigorous brush action. However, any method of applying material to surface 8 which destroys the continuity of this surface is generally not acceptable. Included in the latter catagory are such methods as sandblasting and etching or any other method which physically alters or destroys the surface 8.
Assume that cover 7 is removed from panel 2 and that plate 4 is in contact with surface 8 of panel 2 but that no significant pressure is applied to the plate. The intensity for this condition is illustrated by point 11 on axis 10 which shall hereinafter be referred to as substantially pressureless contact or remote contact. As the plate 4 is moved away from surface 8, as is represented by d on axis 15, the resultant intensity as seen by an observer of viewing surface 3 is illustrated by curve 13. It will be noted that as the backing 4 is moved away from surface 8, the intensity L increases slightly to a maximum level and then decreases.
Curve 12 of FIG. 2 represents the same data as curve 13 except with the cover 7 placed on panel 2. The resultant intensity L" is slightly less than for curve 13, primarily due to the fact that cover 7 shields surface 8 of panel 2 from ambient light. Note that the starting point for curve 12 is also point 1 1, the point designated herein as remote contact.
It is evident from curves l2, l3 and 14 and from experimental data that near optimum conditions for displaying messages on surface 8 is achieved where the material defining the message is in intimate contact with surface 8 and where a backing material is utilized, generally of contrasting color, said backing material being in remote contact with surface 8. As will be seen herein, the phenomenon described above may be utilized in an extremely useful manner to produce display of exceptional performance in terms of light efficiency, intensity, color, and contrast.
Referring to FIG. 3, a display is illustrated which is displaying the message ABC. A cross section of this display is illustrated in FIG. 4. Note that the components, particularly the message 19, spacer and backing material 21 of FIG. 4, are not illustrated to scale but is rather shown out of proportion in order to better illustrate its relationship with the entire display. The display comprises a light-carrying member which is of a general rectilinear configuration, panel 27. Panel 27 may be made of glass, acrylic, plastic materials or any other light transmitting material. For best efficiency, the light transmissability of panel 27 should be approximately equal in all directions throughout the panel. Additionally, all surfaces of the panel, including its edges, should be cleaned and polished before being used. The
viewing surface 17 of panel 27 comprises a rectangular surface upon which the message is viewed. The opposite surface of panel 27, back surface 18, is the surface upon which the message and backing material are placed. The panel 27 is held within a generally rectilinear frame 30. The frame 30 is suitable for containing the panel 27 and for rigidly holding bulbs 24 and 26, adjacent to opposite edges of panel 27. Bulbs 24 and 26 may be any source of light; the light from these bulbs enter panel 27 in the same manner that the light from bulb 6 of FIG. I entered panel 2.
The message 19 comprising the letters ABC is affixed in intimate contact to the back surface 18 of panel 27. The message 19 may consist of any opaque diffusely reflective material which may be brought into intimate contact with surface 18. For example, message 19 may be applied by silk-screening the letters to surface 18 with suitable paints, or by applying thin diffusely reflected opaque tapes or sheets to the surface.
A spacing material such as spacers 20, is applied to the surface of message 19 opposite surface 18. The spacers 20 may comprise tape which is adhered to the message 19. As will be seen, it is preferable to use tape which has an adhesive surface on both sides since this will enable backing material 21 to be readily adhered to the surface of the tape opposite the message 19. Any other suitable spacer material may be utilized provided that it prevents backing sheet 21 from coming in intimate contact with surface 18. For example, a rectangular transparent sheet may be placed over the message 19 and be utilized as a spacer instead of the individual spacers 20 illustrated in FIG. 4. It should be noted that if the message 19 is made of relatively thick material, the spacer 20 may not be required.
Backing material may be any opaque or translucent sheet which is brought in contact with spacers 20. Typically, the backing material 21 will have approximately the same dimension as surface 18 of panel 27. In order to have the optimum display condition, the backing material 21 should be in remote contact with surface 18 while the message 19 is in intimate contact with the surface 18 where the terms intimate contact" and remote contact are as defined above. In addition, the light from bulbs 24 and 26 illustrated by light beams 22 and 23, respectively, should meet the requirements necessary to produce the total reflection within panel 2 and the minimum amount of reflection of light entering the panel 2 as discussed in conjunction with FIG. 1a above. This may be accomplished by proper spacing between the bulbs 24 and 26 at the edges of the panel 27. Or, if necessary, two or more bulbs may be utilized along each of the edges of panel 27 in order to meet the requirements set forth above.
A filter 25 is illustrated within holder 35 adjacent to bulb 24 in FIG. 3. Filter 25 may be any light filter which allows only a predetermined color or groups of colors to pass through it. By utilizing light filters in connection with the light sources utilized to illuminate the display, only light of predetermined colors is permitted to enter the panel 27. Thus, the display seen by an observer may be of any particular predetermined color, by properly selecting the filter 25. It is also possible to use rotating cylindrical filters that enclose the source of light such as filter 97 which is caused to rotate about its axis by motor 98. These filters may comprise areas which filter different colors, thus allowing a continuously changing display.
To restrict the light within panel 27, a diffusely reflective material is placed around the edges of the panel except where the light from bulbs 24 and 26 enter the panels and where the critical angle of the light striking the edge of the body is greater than the critical angle for the material comprising the body. This material may be in intimate contact with the edges. The effect of this material is to cause light reflecting from these edges to be reflected back into panel 27. The remaining uncovered polished edges will relfect light back into the body. Another technique to assure that a maximum amount of light remains within the panel 27 is to insure that the edges of the panel are truly perpendicular relative to the surfaces 17 and 18 of the panel. This assures that the light reflecting from these edges will be reflected back into the panel. Also, optimum contrast can be obtained between the message and the backing material if they are properly selected contrasting colors.
It is also within the scope of the present invention to have a message such as message 19, which does not appear to exist to the observer viewing surface 17 except at a predetermined time. For example, the message may be made not to appear unless bulbs 24 and/or 26 were illuminated. A filter is placed across the viewing surface 17 and the message and backing material having little or no contrast are utilized. For example, a neutral density circular polarizing filter may be used, along with a white message and white backing material. With the combination of the filter andlow contrasting message and backing material, the message is only visible when the source of light is energized. The ambient light which enters the viewing surface does not illuminate the message. This light is polarized when it enters the panel; when this light is reflected from the message or backing material, a change of phase in the light occurs which causes the light to be blocked when it once again strikes the filter. Thus, ambient light does not illuminate the message. The light from the source of light illuminates the message since this light passes directly, through the filter. With a white backing material, white message and white light source, the message appears in white with a dark gray background when the display is illuminated.
Referring to FIG. 5, an alternate embodiment of a display is illustrated wherein a single source of light, bulb 29, is utilized to illuminate a two-sided display. It will be obvious to one of ordinary skill in the art, that any number of bulbs may be utilized with the present embodiment of a two-sided display. The two displays are viewed on viewing surfaces 31 or panels 28. Panels 28 may be similar to panels 27 discussed in conjunction with FIG. 3. The two messages to be viewed are placed on the surfaces of panels 29 opposite the viewing surfaces 31. These messages are illustrated as messages 34 which are in intimate contact with the panels 28. Spacers 33 are utilized in conjunction with the messages 34 and the backing material 32 in a similar manner as were spacers 20 of FIGS. 3 and 4. A common backing mate rial 32, similar to backing material 21 of FIGS. 3 and 4, which is in remote contact with the panels 28 is also utilized. A frame 59 is used to contain the viewing panels 28 and the remainder of the display, including bulb 29. The bulb is held in a similar relative position to the edges of panels 28 as are bulbs 24 and 26 held relative to panels 27, as illustrated in FIGS. 3 and 4. The method of construction of the embodiment of the display illustrated in FIG. is similar to the display illustrated in FIGS. 3 and 4. With the use of this particular embodiment, it is possible to have a display which may be viewed from two sides, each side being capable of displaying a different message and using a common light source. The techniques utilized to obtain optimum efficiency and maximum contrast, for the display of FIGS. 3 and 4, are likewise applicable to the display of FIG. 5.
Referring briefly again to FIG. la, it was noted that in order for an optimum amount of light from bulb 6 to enter panel 2, the angle B should be less than the critical angle for the material comprising panel 2. FIGS. 6 through illustrated methods in which the edges of a light-carrying panel may be shaped in order to allow maximum amount of light from a light source to enter a panel. The shaping of the edges makes these edges as normal as practical to the light from the source of light used to illuminate the display. In FIGS. 6 and 7, a panel 37 is illustrated which is similar to panel 2 of FIG. 1 or panel 27 of FIGS. 3 and 4. A light source, bulb 40, is shown disposed along one edge of the panel. A window 36 having a shape similar to one-half of a hexagon is illustrated cut into the edge of panel 37. It is readily apparent from FIG. 6 that the angle of incidence of light rays 41 upon panel 37 is greatly reduced as a result of window 36. Thus, by properly shaping window 36, it is apparent that the angle discussed in conjunction with FIG. la may be reduced thus allowing the angle of incidence of the light ray 41 to be less than the critical angle and thus allowing more light to enter the panel. FIG. 8 illustrates another edge configuration for a panel 38 comprising a semi-circular section 44 and its regularly shaped edge sections 45. It is obvious that with this configuration, light rays 43 radiating from bulb 42, strike panel 32 at an angle of incidence less than the angle of incidence that would exist if panel 38 had a straight edge. A reflector 39 is coupled to panel 38 and provides additional efficiency from bulb 42 by reflecting light emitted from the bulb into panel 38 as indicated by light rays 46. The configuration of the windows utilized to more effectively capture the light from the light source by the panel, may take any one of a plurality of configurations. The general shape of these windows may be designed utilizing the mathematical tools set forth in the Fresnels equation.
Referring to FIGS. 9 and 10, an alternate embodiment of the present invention is illustrated wherein the light sources are contained within the light-carrying body.
Message 69 comprising the letters XYZ is made of diffusely reflective material which is placed in intimate contact with the surface of transparent sheet 76 facing surface 73 of panel 70. A border 77 is placed around the periphery of the message. This border preferably comprises a very thin material such as a thick coat of paint which is substantially transparent. An opaque, rectangular, diffusely reflective sheet 78 which is larger than and encompasses the message 69 and border 77 is placed in intimate contact with the surface of panel opposite surface 73. With this structure a display is achieved wherein the letters XYZ are dark and are high-lighted by a brilliant border 77.
In FIG. 17, an embodiment of the present invention is illustrated wherein a single source of light, bulb 79, is utilized to illuminate a plurality of displays illustrated as signs 80. Each sign has one of its edges disposed about the periphery of bulb 79. Thus, light from bulb 79 enters each of the signs 80. Each sign 80 may be made in accordance with the teachings of the present invention wherein each sign 80 comprises a lightcarrying body and a message which is in intimate contact with the light-carrying body and a suitable background material in remote contact with the lightcarrying panel.
In FIG. 18, a light-carrying body 82 is illustrated wherein the body is substantially curved or bent. A source of light, bulb 81, is placed at one edge of body 82. It has been found that the light from bulb 81 will substantially remain within light-carrying body 82 and hence, a message displayed on body 82 will be evently illuminated. By tapering the panel 54, such that is becomes thinner the further away it is from the source of light, a more uniform distribution of light is obtained on the panel. Thus, it is possible to use an elongated panel with a single source of light, such as bulb 58, and still obtain a uniform illumination across the entire display.
In FIGS. 13 and 14 still another embodiment of the present invention is illustrated wherein a contrasting band is displayed around the message. The display of these FIGURES comprises a light carrying body, panel 65, a source of light, bulb 60, a message 61 which is in intimate contact with a surface of panel 65, spacers 64 and a backing material 62 which are all similar in construction to the display of FIGS. 3 and 4. A band 62 is affixed to backing material 63 such that it forms an overlapping band around message 61 when viewed from surface 66 of panel 65. The material comprising band 62 may be any material which is contrasting to the material comprising backing material 63. For example, band 62 may be of a different color than the color of backing material 63 or it may have different absorption qualities than material 63. Band 62, for example, may absorb all the light incident on it while material 63 may be diffusely reflected. Band 62 may be formed with a sheet or strip of material adhesively attached to backing material 63 or may be formed by painting or silkscreened on material 63. The effect thus produced by band 62 is a remarkable message contrast of decisive esthetic value Referring to FIGS. and 16, an alternate embodiment of the present invention is illustrated wherein a halo effect is achieved around message 68 and where a bright border 77 is produced around a dark message 69. A light carrying body, panel 70 and a bulb 67 is utilized in this embodiment in the same manner the bulbs and panels have been utilized in the previous embodiments.
A sub-message 74 comprising the letters ABC" is placed in intimate contact with surface 73 of panel 70. This sub-message is made of diffusely reflective material and may be placed on surface 73 in accordance with the teachings of this patent. A transparent viewing sheet 76 is placed over surface 73 of panel 70 with spacers 75 being placed between the sheet and the surface. Thus, the sheet 76 is in remote contact with surface 73 of the panel 70. Message 68 comprising the letters ABC which are slightly smaller in size than the sub-message 74 are placed above the sub-message 74 on the side of the transparent sheet 76 which faces surface 73. The message 68 may be made of any opaque material which may be adhered to transparent sheet 76. A backing material 71, comprising a diffusely reflective material is disposed across the surface of panel 70, opposite surface 73 and is held in remote contact with that surface by means of spacer 72. By utilizing the message 68 on the transparent sheet 76 and by having sub-message 74 in intimate contact with the lightcarrying body, a halo effect is achieved around the message ABC.
Message 69 comprising the letters XYZ is made of diffusely reflective material which is placed in intimate contact with the surface of transparent sheet 76 facing surface 73 of panel 70. A border 77 is placed around the periphery of the message. This border preferably comprises a very thin material such as a thin coat of paint which is substantially transparent. An opaque, rectangular, diffusely reflective sheet 78 which is larger than and encompasses the message 69 and border 77 is placed in intimate contact with the surface of panel 70 opposite surface 73. With this structure a display is achieved wherein the letters XYZ" are dark and are high-lighted by a brilliant border 77.
In FIG. 17, an embodiment of the present invention is illustrated wherein a single source of light, bulb 79, is utilized to illuminate a plurality of displays illustrated as signs 80. Each sign 80 has one of its edges disposed about the periphery of bulb 79. Thus, light from bulb 79 enters each of the signs 80. Each sign 80 may be made in accordance with the teachings of the present invention wherein each sign 80 comprises a lightcarrying body and a message which is in intimate contact with the light-carrying body.
In FIG. 18, a light-carrying body 82 is illustrated wherein the body is substantially curved. A source of light, bulb 81, is placed at one edge of body 82. It has been found that the light from bulb 81 will substantially remain within light-carrying body 82 and hence, a message displayed on body 82 will be evently illuminated. The message, such as the word Exit" and the arrow shown in FIG. 18 may be placed on body 82 in accordance with the teachings of the present invention.
FIGS. 19 and illustrate an embodiment of the present invention which is particularly useful for a lighting panel such as one that would be placed on a cepts of intimate contact and remote contact as defined ceiling. A source of light comprising a bulb 83 is illustrated enclosed within a lens 84. The lens 84 may be any commonly utilized enclosure for containing a light bulb. Light-carrying bodies, such as panel 85, are disposed horizontally about the periphery of bulb 83. These panels may be substantially similar to the lightcarrying body, panel 27, discussed in conjunction with FIGS. 3 and 4. A message such as a decorative pattern 86 is placed in intimate contact with the surfaces 89 of panels 85. A backing material 87 may be placed above the pattern 86 in the same manner that backing material 21 is utilized in conjunction with FIGS. 3 and 4. The resultant structures in addition to its esthetic value, directs light rays which would otherwise be lost downward from the panels 85, thus more efficiently utilizing the light produced by bulb 83.
FIG. 21 illustrates an embodiment of the present invention wherein an elongated source of light such as fluorescent tube 90 is utilized to illuminate two panels 91 which may be similar to panels 85 of FIGS. 18 and 19 and simultaneously illuminate a display containing a message such as panel 92. Panel 92 may be similar in construction to the displays discussed in conjunction with FIGS. 3, 4 and 5.
With reference to the various messages utilized throughout the displays described herein, it has been found that the message appears to be more brilliantly illuminated around its edges than within its center. Thus, by segmenting the message so that it in effect contains a greater number of edges, the entire message appears more brilliant. In FIG. 22, a message comprising the letter A is illustrated wherein a plurality of slits 95 have been cut into the message. These slits increase the number of edges in the message and hence, when the message is utilized as described herein, a more uniform illumination of the message is achieved. This technique is particularly useful for larger messages and has been found to be unnecessary where the message is relatively small.
Thus, numerous embodiments of the present invention have been described which provide optimum displays through use of a light-carrying body, a backing material and a message by properly utilizing the conherein.
I. An illuminated display comprising:
a light-carrying body comprising a material having a critical angle and having at least two opposite flat major surfaces and polished peripheral edges;
a message comprising a diffusely reflective material in intimate contact with one of said opposite surfaces of said body;
a backing material in substantially pressureless contact with said one of said opposite surfaces of said body.
a source of light disposed adjacent to one of said peripheral edges such that light enters the body and is transmitted within said body;
a reflective material in intimate contact with only those sections of said peripheral edges where the angle of incidence along said edges for light from said source of light entering said body and striking said edges is less than approximately said critical angle;
whereby substantially all of the light entering said body will remain in said body since it willbe reflected from either the polished edges or the reflective material thereby resulting in an unusually brilliant display.
2. The display defined in claim 1 wherein said surfaces of said body are rectangular in shape and substantially perpendicular to said edges.
3. The display defined in claim 2 wherein a light filter is disposed between said source of light and said body such that light from said source of light is filtered before entering said body.
4. The display defined in claim 2 wherein said color of said backing material and said message are such as to produce a contrast.
5. The display defined in claim 2 wherein the edges of said body adjacent to a source of light are irregularly shaped such that light from said source striking said edge is relatively normal to said edge.
6. The display defined in claim 2 wherein said body is tapered and the source of light is adjacent to the widest edge of said body.
7. The display defined in claim 1 wherein a border is disposed about the periphery of said message, said border being coupled to said backing material and being contrasting in color to said backing material.
8. The display defined in claim 1 wherein said message contains a plurality of slits forming apertures through which light may pass.
9. The display defined in claim 1 wherein said source of light is disposed within a cavity defined by said body.