Patent Publication Number: US-2013235617-A1

Title: Led edge-lit signage utilizing digital print technology

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation-in-part of U.S. patent application Ser. No. 12/722,781, filed Mar. 12, 2010. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to illuminated signage. In particular, this invention relates to illuminated signage with LED edge lighting. 
     BACKGROUND OF THE INVENTION 
     Illuminated image signage is used where there is insufficient illumination at night for a sign to be seen, or where increased awareness of the sign is desired. Increasingly, image signage is being illuminated using LED edge-lighting. LEDs offer low voltage DC operation, low power consumption, long life without maintenance, and rugged construction that is immune to vibration and shock. 
     Edge lighting with LEDs provides the additional advantage of enabling extremely thin signs that are esthetically pleasing. LEDs are well suited to such applications because of their small size and directional propagation of light. 
     The association of LED edge-lit print-based signage with a changeable digital display offers the opportunity to provide the attraction of an aesthetically pleasing edge-lit sign along with the flexible content available through a changeable digital display. 
     U.S. Patent Publication No. 2011/0279357 to Leeks discloses a display assembly with top and bottom display portions. The top display portion comprises a digital LED scroller unit, while the bottom display portion comprises a printed panel. The printed panel is lit by lighting from the LED scroller unit. The contents of the LED scroller unit may be adjusted and controlled through wireless communications. However, as the printed panel is illuminated only on one edge by incidental lighting, its illumination may appear uneven. Furthermore, the LED scroller unit is limited in its display capabilities to mainly textual information in a static or scrolling form. 
     It is therefore an object of this invention to provide an effective visual display that includes a properly illuminated LED edge-lit sign as well as a changeable digital display whose contents and layout can easily be customized and adjusted. 
     These and other objects of the invention will be better understood by reference to the detailed description of the preferred embodiment which follows. Note that not all of the objects are necessarily met by all embodiments of the invention described below or by the invention defined by each of the claims. 
     SUMMARY OF THE INVENTION 
     In one aspect, the invention comprises a display assembly having a centrally disposed changeable digital display and a surrounding edge-lit panel, the lighting being directed perimetrally outward from the digital display into the inside edges of the surrounding static image panel. 
     In another aspect, a plurality of light sources are arranged around the perimeter of the digital display, the light sources being directed radially outward from the digital display into the inside edges of the surrounding edge-lit panel. 
     In another aspect, the digital display is mounted in a housing. The housing includes a perimetral channel in which the outwardly directed light sources are housed. 
     In yet a more particular aspect, the channel includes an outer wall against which the edge-lit panel abuts. In another aspect, the outer wall is provided with an unveven surface to enhance diffusion of the light traversing the wall into the edge of the edge-lit panel. 
     In a further aspect, a bezel is secured to the housing to mask the light sources from viewing from the front of the display assembly. 
     In another aspect, the digital display may be configured to segregate the display into a plurality of separately defined zones, each of which may be assigned a shape, size, layout, content or a schedule independently of the other zones. 
     In yet another aspect, the display assembly may be configured to determine the mode of operation of the light sources that illuminate the panel or faceplate and according to a user-defined schedule. 
     The foregoing was intended as a broad summary only and of only some of the aspects of the invention. It was not intended to define the limits or requirements of the invention. Other aspects of the invention will be appreciated by reference to the detailed description of the preferred embodiment, including the drawings, whether or not those aspects are summarized in this section. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be described by reference to the detailed description of the preferred embodiment and to the drawings thereof in which: 
         FIG. 1  is a perspective view of a top edge-lit LED light panel used in the preferred embodiment of the invention; 
         FIG. 2  is a perspective view of a portion of the light panel of  FIG. 1  illustrating internal reflection from an edge of the panel; 
         FIG. 3  is a perspective view of a portion of the light panel showing a matrix of light-diffusing hexagon dots on the front surface of the panel; 
         FIG. 4  is an exploded view of an illuminated sign according to the preferred embodiment; 
         FIG. 5  is a rear perspective view of an image-carrying sheet according to the preferred embodiment; 
         FIG. 6  illustrates a completed sign with images according to the preferred embodiment, including the use of clear windows to present a variable digital display component of the image; 
         FIG. 7  is a front perspective view of a display assembly according to an alternative embodiment of the invention; 
         FIG. 8  is a front view of a display assembly according to the alternative embodiment with a faceplate of a different shape and having a different static image thereon, and without the rear chassis and pedestal; 
         FIG. 9  is a rear perspective view of the digital display mounted in a housing and further comprising a plurality of light sources secured around the perimeter of the digital display by means of a chassis seated in a perimetral channel of the housing, with the light sources directed radially outward from the digital display; 
         FIG. 10  is a an enlarged view of a corner of the structure of  FIG. 9  more clearly showing the light sources; 
         FIG. 11  is a close up perspective view of the structure of  FIG. 9  more clearly showing the channel and the seating of the chassis and light sources therein; 
         FIG. 12  is a substantially edge view of the faceplate portion of the display assembly; 
         FIG. 13  is a substantially front view of the faceplate; 
         FIG. 14  shows the display assembly without the bezel and with the faceplate only partially mounted on the housing so as to reveal the inside edge of the faceplate in relation to the light sources seated in the housing; 
         FIG. 15  shows the digital display seated in the housing; 
         FIG. 16  is a close up view of a corner of the housing with the digital display seated therein and more clearly showing the perimatral channel of the housing; 
         FIG. 17  is a close up view of an edge of the housing showing the transparent outer wall of the housing channel and the light sources visible therethrough. The rear chassis of the display assembly is also partially visible in this view; 
         FIG. 18  is a front view of the display assembly without the rear chassis or the mount, but showing the digital display, the faceplate and the bezel; 
         FIG. 19  is an edge view of the assembly of  FIG. 18 ; 
         FIG. 20  is a bottom view of the display assembly without the faceplate and with the bezel partially installed; 
         FIG. 21  is a bottom view of the display assembly without the faceplate and with the bezel installed; 
         FIG. 22  is a bottom edge view of one side of the display assembly without the faceplate and with the bezel installed showing the seat for receiving the faceplate; 
         FIG. 23  is a exploded perspective view of the chassis and the housing with the digital display seated in the housing; 
         FIG. 24  is a further perspective exploded view of the chassis and the housing with the digital display seated in the housing; 
         FIG. 25  is a rear view of the chassis and the light sources mounted thereon; 
         FIG. 26  is a bottom perspective view of the chassis and the light sources mounted thereon; 
         FIG. 27  is a top perpsective view of the chassis and the light sources mounted thereon; 
         FIG. 28  is a corner view of the digital display seated in the housing, with the faceplate installed against and on the housing, and a bezel partially mounted on the housing to retain the digital display and the faceplate; 
         FIG. 29  is a bottom view of the display assembly but not showing the entire lower mount; 
         FIG. 30  is a bottom perspective view of the display assembly but without the bezel such that the light sources are visible to a viewer of the assembly; 
         FIG. 31  is a partial view of the front of the digital display seated in the housing and showing the channel; 
         FIG. 32  is a rear view of the digital display seated in the housing and showing the ribbon connector; 
         FIG. 33  is partial edge view of faceplate mounted on the housing; 
         FIG. 34  is a further partial edge view of the faceplate mounted on the housing; 
         FIG. 35  is a partial front perspective view of the faceplate mounted on the housing and also showing the digital display seated in the housing; 
         FIG. 36  is an edge view of the faceplate being only partially installed against the outer wall of the housing; 
         FIG. 37  is a corner view of the housing with a partial view of the digital display seated therein and showing the aperture for receiving the bezel post; 
         FIG. 38  is a partial corner view of the housing, the digital display seated therein and the rear housing of the unit; 
         FIG. 39  is a front view of the rear housing, the lower mount and base and showing the circuit board mounted in the rear housing; 
         FIG. 40  is a rear view of the rear housing, the lower mount and the base; 
         FIG. 41  is a side view of the assembled display assembly; 
         FIG. 42  is a flowchart of the configuration steps for the digital display; and, 
         FIG. 43  illustrates various digital display zone assignments according to the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       FIG. 1  illustrates a top edge-lit LED light panel  10  used in the preferred embodiment of the invention. Light panel  10  may consist of a single sheet of  6  mm transparent acrylic. As is known, LEDs are provided at or near one or more edges of the panel to propagate light within the body of the panel. The edges  12  of the sheet are typically provided with a reflective material (which may be white paint) to reflect the light internally ( 17 ) as illustrated in  FIG. 2 . In the preferred embodiment, the panel is lit ( 11 ) only from its top edge, but the invention is equally applicable to lighting from other edges or from a plurality of edges. 
     Referring to  FIG. 4 , the preferred embodiment includes an image-carrying sheet  18 , the light panel  10  mounted co-planar with and to the print side of the image-carrying sheet  18  (opposite the viewing side of the image-carrying sheet  18 ) and a reflective back plate  20  mounted coplanar with and behind the light panel  10  (on the opposite side of the light panel from the image-carrying sheet). A gap  22  may be provided between the light panel  10  and the reflective back plate  20 , as discussed below. 
     Referring now to  FIG. 3 , frontward diffusion of the light from the light panel may be provided by using a matrix of printed, engraved, silkscreened or etched elements such as dots  14  on the front surface (viewer side) of light panel  10  that faces the image-carrying sheet. The dots, which in the preferred embodiment are hexagonal, provide a diffusing rather than a reflective surface, allowing the light to pass through the front surface  16  of the panel. 
     Given that the preferred embodiment of the light panel is preferentially edge-lit from the top edge, in order to provide a uniform backlighting of the image the dot matrix is provided with a density gradient from a low density adjacent the lit edge to a high density distal from the lit edge. Other arrangements may be contemplated where more than one edge is lit, or where it is desired to provide non-uniform backlighting for the image. 
     Referring to  FIG. 4 , approximately half the light scattered within light panel  10  tends to exit the rear of the light panel. This light is reflected back to and through the light panel  10  by the reflective back plate  20 . In the preferred embodiment the back plate is made of 2 mm thick Dibond (a trademark of Alcan Composites USA Inc.) or equivalent white painted aluminum sheet. A gap  22  of 2-3 mm is provided between light panel  10  and back plate  20 . Gap  22  facilitates the positioning between the back plate and the light panel of a digital display if an appropriate window is provided in the light panel and in the image-carrying sheet, as discussed below. 
     Referring to  FIG. 5 , a reverse  17  of the image to be illuminated may be directly printed digitally on the back (print side) of a ‘graphic front plate’ (image-carrying sheet  18 ) made of  2 mm of an otherwise clear acrylic. Once the image has been printed, the surface of the image, again being the print side that faces the light panel  10 , is then printed or silkscreened so as to uniformly cover the printed image with a translucent layer  15  of white. In the preferred embodiment, the translucent layer is 4 microns thick white ink and is applied using an ink-jet flatbed printer. The layer  15  appears to be effective to enhance the visibility and uniform brightness of the colors of the image  17 . A suitable ink is Anapurna White G1 Ink by Agfa comprising 60-80% acrylate, 5-10% phosphine oxide, diphenyl and 1-5% benzophenone but it is believed that other inks may also be suitable provided that they provide a white translucent covering for the back of the image-carrying sheet. 
     The image-carrying sheet  18 , the light panel  10  the backplate  20  and the gap  22  are retained in the assembly by a suitable frame for example an extruded housing  23 . 
     As seen in  FIG. 4 , light panel  10  and the image-carrying sheet  18  may be provided with overlapping transparent or clear windows (which may be cut-outs)  24 ,  26  allowing changeable digital information to be presented and viewed by means of a changeable digital display  25  secured behind the windows, resulting in a completed sign having the appearance shown in  FIG. 6 . This provides the opportunity for an illuminated image with both static and variable components. 
     Where a clear window is not required, an image-carrying sheet  18  that is translucent rather than transparent may be used. In such case, the image would be printed to the front of the image-carrying sheet  18  rather than a negative of the image being printed to the back of the sheet. 
     As the invention enables the use of printing for the image-carrying sheet, rather than engraving or etching, a customer can transmit the desired image to the sign maker who can then print directly from the image file provided by the customer. 
     Another embodiment of a display assembly offering both static and variable components is illustrated in  FIGS. 7 to 43 . Referring to  FIG. 7 , display assembly  100  comprises a centrally disposed changeable digital display  105  that is substantially surrounded by an edge-lit panel  110  that acts as a surrounding faceplate. 
     The outer perimeter  112  of the faceplate  110  may take any number of shapes according to a customer&#39;s preference or specifications. As will be detailed below, lighting to illuminate the edge-lit faceplate is directed outward from the perimeter of the digital display  105  and into the side edges of the surrounding faceplate panel  110 . Preferably, the faceplate  110  includes a static image printed thereon as shown in  FIGS. 7 and 8 , but the faceplate may also be provided without any particular image so as to nonetheless frame the digital display with an illuminated panel. 
     As is best seen in  FIGS. 9-11  and  14 , a plurality of light sources  155  are secured around the perimeter  109  of the digital display  105 . The light sources  155  are directed radially outward (in the direction shown by arrows  156 ) from the digital display  105  into the inside edges  172  of the surrounding edge-lit faceplate  110 . 
     Referring primarily to  FIGS. 15 and 16 , the digital display  105  of this embodiment is mounted in a housing  115  that substantially surrounds the perimeter of the digital display  105 . The housing  115  may be made for example of molded plastic. Housing  115  has a perimetral channel  120  in which the outwardly directly light sources  155  are to be housed. 
     Channel  120  includes an outer wall  130  against which the edge-lit faceplate  110  abuts. As best seen in  FIGS. 11 and 17 , the outer wall  130  is provided with an uneven surface  131  to enhance diffusion of the light traversing the wall  130  into the edges  172  of the edge-lit faceplate  110  in the completed assembly. 
     As seen in  FIGS. 18 and 19 , a bezel  175  is secured to the housing  115  to mask the light sources  155  from being seen from the front of the display assembly  100 . The bezel  175  also serves to sandwich the faceplate  110  between the bezel  175  and the housing  115 . The seat  178  formed between the bezel  175  and the housing  115  is best appreciated by reference to  FIGS. 20 ,  21  and  22 . 
     In the preferred version of this embodiment, the digital display  105  is an LCD screen and the light sources  155  are LEDs mounted on a chassis  140  that is seated in channel  120 . Chassis  140  (on which the light sources  155  are mounted) is best illustrated in  FIGS. 25-27 . It comprises a substantially flat chassis surface  145  and a chassis wall  150  projecting substantially perpendicular to the chassis surface  145  and extending along the perimeter of the chassis surface  145 . A plurality of LED lights  155  are affixed to the outer surface of the chassis wall  150 . The LED lights  155  may be spaced apart from one another, but they extend along the entirety of the chassis wall  150 , forming a perimeter around the chassis  140 . The LED lights  155  are electrically connected to one another to allow for easier control and operation of all of the LED lights  155 . Preferably, the LED lights  155  are oriented such that the emitted light is primarily directed outwardly and substantially perpendicularly to the surface of the chassis wall  150 . 
     Referring to  FIG. 15 , channel  120  comprises an inner wall  125  and a transparent outer wall  130 , which is spaced from the inner wall  125 . A lip  135  projects outwardly from the outer wall  130  to act as a support surface for one side of the faceplate  110 . The channel  120  opens on the side of the housing  115  that faces the rear of the display assembly  100 . When the chassis  140  is seated in and secured to the housing  115 , the chassis wall  150  abuts snugly into the channel  120  against its inner wall  125 .  FIG. 10  shows the chassis  140  seated in channel  120 , although inner wall  125  is now obscured by wall  150  of the chassis that now abuts against it. The LED lights  155  fit within the space of channel  120  (i.e. between the inner and outer walls  125 ,  130 ). Because the outer walls  130  are transparent, the light emitted by the LED lights  155  is able to pass through the outer walls  130  of channel  120 . In  FIG. 17 , the LEDs  155  are visible through the transparent walls  130  of the housing  115 . 
     As seen by reference to  FIGS. 13 ,  14 ,  28  and  31 , an interior opening  160  of faceplate  110  is seated over lip  135  of housing  115  front of the housing  115 . The opening  160  is sized such that when the faceplate  110  is placed over the front of the housing  115 , the faceplate  110  snugly abuts the outer walls  130  of the channel  120  and rests on the lip  135 . The faceplate  110  may comprise a printed surface  165  with a clear coating  170  on top of the printed surface  165  and a reflective backing  174  on the rear surface of the faceplate  110  The light from the LED lights  155  passes through the outer walls  130  of channel  120  to illuminate the printed surface  165  of the faceplate  110 . 
     The faceplate  110  is secured in place by bezel  175  that sits over the faceplate  110 , sandwiching the faceplate  110  against the housing  115 . The bezel  175  comprises posts  180  extending from the rear of the bezel  175 . The posts  180  extend into and through corresponding apertures  185  located on the housing  115 . The posts  180  and the apertures  185  assist in ensuring that the bezel  175 , faceplate  110 , and the housing  115  are aligned correctly. When the bezel  175  is placed over the faceplate  110  and the housing  115 , the bodies of the LEDs  155  on the chassis  140  are not visible from the front as they are hidden from view by the bezel  175 . 
     Referring now to FIGS.  29  and  39 - 41 , the display assembly  100  further comprises a rear housing  190 . The bezel  175 , the faceplate  110 , and the housing  115  are attached to the rear housing  190 . The rear housing comprises one or more housing receptacles  195  that correspond in location to the posts  180  of the bezel  175 . The posts  180  fit within the housing receptacles  195  and by using suitable fasteners, such as screws to engage the housing receptacles  195  so that the bezel  175  (along with the faceplate  110  and the housing  115 ) may be securely attached to the rear housing  190 . The rear housing  190  further comprises a circuit board  200  for providing control functions for the digital assembly  100 . A ribbon connector  205  provides data and power from the circuit board  200  to the digital display  105 . An LED power connector  210  provides power from the circuit board  200  to the LED lights  155 . 
     A lower mount  215  may extend from the bottom of the rear housing  190 . The mount  215  may comprise a base  220  that allows the digital assembly  100  to be placed on a flat surface. One or more buttons may be present on the rear housing  190  to allow for the user to control and operate the display assembly  100 . 
     The display assembly  100  provides for the digital display  105 , which is capable of displaying both static images and video, to be surrounded by an edge-lit illuminated signage. 
     The invention further provides that the contents of the digital display  105  may be customized and controlled by the user, either wirelessly or manually by connecting a suitable media device (preferably a USB drive) to a port on the rear housing  190 . User interface software is made available to users to configure the display modes of digital display portion of the assembly, as well as the LEDs that illuminate the faceplate. The user interface software allows the user to create any number of display configurations that are saved to memory as generally illustrated by the flowchart of  FIG. 42 . Once saved, the configurations may be communicated to the display assembly by a wireless network connection that is enabled by on-board networking software and wireless communication hardware or by means of a USB drive in the USB port of the rear housing  190 . 
     Once the configurations have been communicated to the display assembly, they are saved ( 272 ) in memory on the circuit board  200 . The user may thereafter allow the display assembly to operate according to a schedule to sequence the various configurations, or according to a specific one of the configurations, which may itself have a particular schedule associated with it as described below. 
     The display configurations include the ability of the user to determine ( 252 ) the lighting status and mode of the LEDs  155  that illuminate the faceplate  110 . This can include having the LEDs on, off or flashing according to a particular frequency and duty cycle, and fade in and fade out features. The operation of the LEDs is also customizable according to a schedule, allowing the user to select a particular state of operation according to a user-determined schedule ( 254 ). 
     The contents of the digital display  105  may also be customized by dividing the digital display  105  into a plurality of virtual zones. For example, the user may define a number ( 256 ) of display zones  1 ,  2 ,  3 ,  4 ,  5  such as are shown in  FIG. 42 . The shape and size of each zone is determined by the user ( 258 ). The virtual zones are specified through the user interface and the parameters of each zone are communicated ( 272 ) to the memory on circuit board  200  as part of the display configurations. Although five zones are illustrated in  FIG. 42 , any number of zones may be allowed. In the preferred embodiment, up to six zones are allowed, with the user having the ability to determine the shape (preferably rectangular) and size of each zone, as well as the layout ( 260 ) of the zones in relation to one another. 
     These pre-configured layouts allow the user to quickly switch between different layouts without the need to re-define the dimensions or locations of the zones  1 ,  2 ,  3 ,  4  and  5  each time a specific layout is needed. Instead, the user simply chooses from one of the pre-configured layouts and proceeds to specifying the content of the zones  1 ,  2 ,  3 ,  4  and  5 . The pre-configured layouts may also be later edited and saved by the user. 
     The user interface also allows the user to define ( 262 ) the content of each zone in each layout, be it video or a static image. A plurality of alternative contents may be defined as a contents set for each zone to accommodate a scheduling of the content for each zone. 
     The layout of the zones and which content from the content set will be played may be controlled by a schedule ( 264 ), which allows the contents to be set according to the time or date. For example, the contents of the digital display  105  may be set up so that one layout with particular content in each zone appears between 12:00 am and 12:00 pm, while another layout (perhaps with differing sizes, numbers, locations, and/or content of the zones  1 ,  2 ,  3 ,  4  and  5 ) appears between 12:00 pm and 12:00 am. In another example, the contents may be set up so that one layout appears from Monday to Friday, and another layout appears on Saturday and Sunday. This may be pre-programmed into the digital display  105 . 
     The ability to pre-program or change the display content according to zones enables a user to customize the presentation of the digital display  105  component of the display assembly  100  without necessarily changing the entirety of the content of the digital display. For example, a user may pre-configure a plurality of contents for, for example, two out of five zones, and using a schedule, determine which of the contents will be played (in the case of video) or shown (in the case of a static image) at a given time. This approach avoids the need to create an entire composite display for each scheduling time segment, thus making it easier for a user to change the overall display from time to time. It also makes it easier for a user to modify the digital display without necessarily changing all aspects of the display. 
     It will be appreciated by those skilled in the art that the preferred and alternative embodiments have been described in some detail but that certain modifications may be practiced without departing from the principles of the invention.