Abstract:
The exemplary embodiments herein provide a sealed transparent LCD assembly having a front and rear glass panel with a spacer positioned between the two panels to provide a sealed cavity containing a liquid crystal display (LCD). A wireless transmitter/receiver may be placed within the sealed cavity to receive image or video data wirelessly. The sealed transparent LCD assembly may be used with a display case which defines a cavity housing a second wireless transmitter/receiver which can push the image or video data to the wireless transmitter/receiver contained within the sealed cavity between the two glass panels.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to U.S. Provisional Application No. 62/013,225 filed on Jun. 17, 2014 and is herein incorporated by reference in its entirety. This application also claims priority to U.S. Provisional Application No. 62/012,559 filed on Jun. 16, 2014 and is herein incorporated by reference in its entirety. 
     
    
     TECHNICAL FIELD 
       [0002]    Embodiments generally relate to video transmission systems for transparent liquid crystal displays (LCD) sometimes used within display cases. 
       BACKGROUND OF THE ART 
       [0003]    Display cases are used in a number of different retail establishments for illustrating the products that are available for sale. In some instances these display cases may be coolers or freezers which are placed in grocery stores, convenience stores, gas stations, restaurants, or other retail establishments. In other instances these display cases may be non-refrigerated transparent containers used in a jewelry or watch store, bakery, deli, antique shop, sporting goods store, electronics store, or other retail establishments. While the design and appearance of the product itself does provide some point-of-sale (POS) advertising, it has been found that additional advertising at the POS can increase the awareness of a product and in turn create additional sales. 
         [0004]    Most retail establishments already contain some POS advertising, and depending on the type of establishment the proprietor may want to limit the amount of ‘clutter’ in the retail area—resulting in a very limited space for additional POS advertising. It has now become desirable to utilize the transparent glass that is typically placed in display cases with additional POS advertising. Most notably, it has been considered that transparent LCDs may be positioned along with the transparent glass and could display additional advertising materials while still allowing a patron to view the products inside the display case. 
       SUMMARY OF THE EXEMPLARY EMBODIMENTS 
       [0005]    An exemplary embodiment provides a wireless transmission system for a transparent LCD assembly. A first wireless transmitter/receiver is position in a cavity below the display case while a second wireless transmitter/receiver is positioned on a mounting plate above or below the LCD. The LCD, mounting plate, and second wireless transmitter/receiver are preferably sandwiched between a front and rear glass. The mounting plate is preferably bonded to and in thermal communication with the rear glass so that any heat generated by the wireless transmitter/receiver can be transferred to the rear glass for removal by natural or forced convection. 
         [0006]    LEDs are preferably arranged along the top and bottom edges of a two way light guide which permits the light to exit both the front and rear surface of the light guide. The top LEDs are preferably placed in thermal communication with a top plate which is placed in conductive thermal communication with the rear glass. Similarly, the bottom LEDs are preferably placed in thermal communication with a bottom plate which is also placed in conductive thermal communication with the rear glass. The top and bottom plates permit the heat to spread out and transfer to the rear glass where it can be removed by forced or natural convection. 
         [0007]    The foregoing and other features and advantages of the present invention will be apparent from the following more detailed description of the particular embodiments, as illustrated in the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    A better understanding of an exemplary embodiment will be obtained from a reading of the following detailed description and the accompanying drawings wherein identical reference characters refer to identical parts and in which: 
           [0009]      FIG. 1  is a perspective view of a display case having a transparent LCD assembly with an exemplary wireless transmission system. 
           [0010]      FIG. 2  is a perspective view of the display case of  FIG. 1  where the door has been opened. 
           [0011]      FIG. 3  is a perspective view of the display case of  FIG. 1  showing the cavity for electronic devices as well as the location of Detail A. 
           [0012]      FIG. 4  is a front view of Detail A shown in  FIG. 3 . 
           [0013]      FIG. 5  is a perspective view showing a lower mounting plate and various electronic devices. 
           [0014]      FIG. 6  is a perspective view showing an upper mounting plate. 
           [0015]      FIG. 7  is a perspective view of a partially assembled exemplary embodiment of a sealed transparent LCD assembly. 
           [0016]      FIG. 8  is a perspective view of the sealed transparent LCD assembly  200  of  FIGS. 1-2 . 
       
    
    
     DETAILED DESCRIPTION 
       [0017]    The invention is described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the exemplary embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, the size and relative sizes of layers and regions may be exaggerated for clarity. 
         [0018]    The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. 
         [0019]    Embodiments of the invention are described herein with reference to illustrations that are schematic illustrations of idealized embodiments (and intermediate structures) of the invention. As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, embodiments of the invention should not be construed as limited to the particular shapes of regions illustrated herein but are to include deviations in shapes that result, for example, from manufacturing. 
         [0020]    Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein. 
         [0021]      FIG. 1  is a perspective view of a display case having a transparent LCD  200 . Generally, the display case includes a housing  105 , to which a door frame assembly  100  is fastened. In this embodiment, a cavity  110  is provided below the door frame assembly  100  where various electronic devices  111  for operating the transparent LCD assembly  200  can be located. The electrical devices  111  may include any or all of the following: power modules, timing and control board (TCON), video player, hard drive/electronic storage, microprocessor/CPU, wireless transmitter/receiver, cellular data transmitter/receiver, and internet connectivity. At least some of the electrical devices  111  are in electrical communication with the transparent LCD  200 . 
         [0022]      FIG. 2  is a perspective view of the display case of  FIG. 1  where the door has been opened. The transparent LCD  200  is preferably sandwiched between a front glass  225  and rear glass  205 . Also preferably sandwiched between the front and rear glass  225 / 205  is an upper plate  216  and a lower plate  215 , each of which are preferably attached to the rear glass  225  such that heat from the plates can be conductively transferred to the rear glass  225  and removed by natural or forced convection. 
         [0023]    In an exemplary embodiment, the upper and lower plates are preferably bonded to the rear glass  205  through adhesive transfer tape. An exemplary adhesive transfer tape for this purpose would be 468 MP, available commercially from 3M™ of St. Paul, Minn. www.3M.com/converter In order to illuminate the transparent LCD  200 , one or more printed circuit boards (PCBs) each containing a plurality of LEDs is preferably in conductive thermal communication with either the upper, lower, or both plates. In this way, heat that is generated by the LEDs can be transmitted to the PCB and eventually transferring to the rear glass  205  where the heat can dissipate through natural or forced convection. 
         [0024]      FIG. 3  is a perspective view of the display case of  FIG. 1  showing the cavity for electronic devices  111  as well as the location of Detail A.  FIG. 4  is a front view of Detail A shown in  FIG. 3 . Here, a wireless transmitter/receiver  450  is shown within the cavity  110  and included with the electrical devices  111 . 
         [0025]      FIG. 5  is a perspective view showing a lower mounting plate  215  and various electronic devices  400  in electrical communication with the LCD  200 . A second wireless transmitter/receiver  455  is also preferably positioned on the lower mounting plate  215  and may communicate electronically with the wireless transmitter/receiver  450  shown within the cavity  110 . A plurality of different signals can be transmitted between the two wireless devices  450 / 455  including but not limited to: image/video data, visual alerts, image inspection/test patterns, temperature of the display case, and feedback data from the LCD  200  such as brightness, color saturation, color temperature, gamma, and contrast ratio. 
         [0026]    As noted above, preferably the electronic devices  400  are in conductive thermal communication with the plate  215  which is preferably bonded to and in conductive thermal communication with the rear glass  205  so that heat generated by the electronic devices  400  can be removed. Similarly,  FIG. 6  is a perspective view showing an upper mounting plate which can also be used to mount various electronic devices and is also preferably bonded to and in conductive thermal communication with the rear glass  205 . 
         [0027]    The wireless devices  450 / 455  can operate under any form of wireless networking technology, including but not limited to: WPAN, WLAN, a wireless mesh network, or GAN. Specifically regarding the architecture for a WLAN network, these could include but are not limited to stations, basic service set, extended service set, and a distribution system. Further regarding the types of wireless LANs, these could include but are not limited to peer-to-peer, bridge, and a wireless distribution system. Any form of general encryption method can be used with the exemplary embodiments herein. 
         [0028]    In a preferred embodiment, the lower plate  215  would extend horizontally as far as possible, preferably to the same horizontal width as the LCD  230  and may extend 4-14 inches in vertical width, depending on the application. Although shown attached to the lower plate  215 , electrical devices  400  could also be mounted to the upper plate  216 . 
         [0029]    In a preferred embodiment, the upper plate  216  would extend horizontally as far as possible, preferably to the same horizontal width as the LCD  200 . The upper plate  216  may also extend 4-14 inches in vertical width, depending on the application. While not required, it is also preferred that the lower plate  215  and the upper plate  216  are within 15% of the same surface area. In other words, it is preferred that the plates  215 / 216  are substantially the same surface area. This is not required however, as some embodiments may require a larger surface area for the plate which would contain the electrical devices  400 , or a larger surface area for the top plate  216  as compared to the bottom plate  215 . It is preferred that the plates are both metallic, and most preferably aluminum, but they can be any material that has good thermal conductivity. 
         [0030]      FIG. 7  is a perspective view of a partially assembled exemplary embodiment of a sealed transparent LCD assembly  200 . Here, the front glass  225  has been removed to show the interior of the sealed assembly  200 . This view shows the rear glass  205  with the spacer  300  attached around the perimeter of the glass  205 . The various electronic devices  400  as well as the second wireless transmitter/receiver  455  are shown attached to the bottom plate  215  and sealed between the rear glass  205  and front glass  225  (not shown here). 
         [0031]      FIG. 8  is a perspective view of the sealed transparent LCD assembly  200  of  FIGS. 1-2 . Generally speaking, the assembly includes a spacer  300  which is sandwiched between a front glass  225  and rear glass  205 . These components are preferably sealed together with an inert gas filling the sealed enclosure. The components are preferably gaseously sealed so that outside gas cannot penetrate into the assembly and any gas sealed within the assembly cannot substantially escape. 
         [0032]    Although not required for every embodiment, argon gas has been found to be preferred as the gas sealed within the assembly. For gaseously sealing these components together, it is preferable to use a hot melt polyurethane. Preferably, the spacer  300  is the Super Spacer® Standard from Quanex in Cambridge, Ohio www.quanex.com. In an exemplary embodiment, the spacer  300  would be a flexible foam that contains a desiccant and has a pressure sensitive acrylic adhesive on the front and back edges of the spacer which would be used to bond with the front and rear glass. 
         [0033]    The embodiments of the wireless communication and transparent LCD system described herein can be used with any number of display case designs, either temperature controlled or not, and with doors that open or glass that remains stationary. Although shown here with a transparent LCD, the wireless system could be used with a traditional backlit LCD as well. 
         [0034]    Having shown and described a preferred embodiment of the invention, those skilled in the art will realize that many variations and modifications may be made to affect the described invention and still be within the scope of the claimed invention. Additionally, many of the elements indicated above may be altered or replaced by different elements which will provide the same result and fall within the spirit of the claimed invention. It is the intention, therefore, to limit the invention only as indicated by the scope of the claims.