Patent Abstract:
An apparatus for controlling a backlight is disclosed. The apparatus includes a housing and door. A transparent liquid crystal display and associated backlight is positioned between front and rear glass panels of said door. A door sensor is positioned to detect if the door is open or shut, and a controller connected to the backlight and door sensor measures the amount of time that has passed between door openings and drives the backlight at various levels based upon the elapsed time.

Full Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the priority of U.S. Provisional Application No. 62/061,950 filed Oct. 9, 2014. 
     
    
     TECHNICAL FIELD 
       [0002]    Embodiments generally relate to systems for reducing the energy usage of transparent liquid crystal displays (LCD) 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 system for reducing the energy usage of a transparent liquid crystal display by tracking the activity of the opening/closing of the door containing the transparent liquid crystal display. 
         [0006]    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 
         [0007]    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: 
           [0008]      FIG. 1  is a perspective view of a refrigerated display case having a transparent LCD assembly. 
           [0009]      FIG. 2  is a perspective view of the refrigerated display case of  FIG. 1  where the door has been opened. 
           [0010]      FIG. 3  is a perspective view of the refrigerated display case of  FIG. 1  showing the cavity for electronic devices as well as the location of Detail A. 
           [0011]      FIG. 4  is a front view of Detail A shown in  FIG. 3 . 
           [0012]      FIG. 5  is a perspective view showing a lower mounting plate and various electronic devices. 
           [0013]      FIG. 6  is a perspective view showing an upper mounting plate. 
           [0014]      FIG. 7  is a block diagram for an exemplary embodiment of the electronic components within the door as well as the electronic components in the cavity below the door. 
           [0015]      FIG. 8  is a screen shot of an exemplary user interface for operating a power saving mode. 
           [0016]      FIG. 9  is a flow chart for an exemplary logic structure for operating the optional power saving mode. 
           [0017]      FIG. 10  is a flow chart for another exemplary logic structure for operating the optional power saving mode. 
           [0018]      FIG. 11  is an electrical schematic representation of an exemplary embodiment of the system for tracking and analyzing display case usage. 
       
    
    
     DETAILED DESCRIPTION 
       [0019]    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. 
         [0020]    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. 
         [0021]    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. 
         [0022]    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. 
         [0023]      FIG. 1  is a perspective view of a refrigerated display case  50  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. 
         [0024]      FIG. 2  is a perspective view of the refrigerated 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. 
         [0025]    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  217  is preferably in conductive thermal communication with either the upper, lower, or both plates. In this way, heat that is generated by the LEDs  217  can be transmitted to the PCB and eventually transferring to the rear glass  205  where the heat can dissipate through natural or forced convection. 
         [0026]    The LEDs  217  may serve as a backlight for the transparent LCD  200  and may be arranged to direct light near or through the transparent LCD  200 . A light guide may be used, but is not required. The light guide would preferably be placed between the transparent LCD  200  and the rear glass  205 . 
         [0027]      FIG. 3  is a perspective view of the refrigerated display case of  FIG. 1  showing the cavity for electronic devices as well as the location of Detail A. Also shown in this figure is the temperature sensor  620  which is in electrical communication with the electronic devices  111 . 
         [0028]      FIG. 4  is a front view of Detail A shown in  FIG. 3 . Here, various electronic devices  111  are shown within the cavity  110 , and would preferably include a CPU and a wireless transmitter/receiver. Also shown here is a door sensor  600  which is positioned to determine whether the door is currently open or not. The door sensor  600  is preferably in electrical communication with the CPU, which contains an electrical connection to either an internet or satellite network. 
         [0029]      FIG. 5  is a perspective view showing a lower mounting plate  215  and various electronic devices  400  in electrical communication with the LCD  200  as well as the electronic devices  111 . 
         [0030]    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 . 
         [0031]      FIG. 7  is a block diagram for an exemplary embodiment of the electronic components  400  within the door as well as the electronic components  111  in the cavity  110  below the door. The antennas  115  can be cellular network antennas or can be Wi-Fi receiving devices. In some embodiments, the modem may be connected through a hard-wired internet connection rather than cellular or wireless. Preferably, the video signal from the media player is transmitted to the receiving board  117  through wireless communication, although this is not required. The modem may be configured to receive data and transmit said data to various components, such as the Nexus board  116 . The data may include instructions for operation of the LEDs  217 . 
         [0032]    The Nexus board  116  and the Receiver board  117  each contain a wireless device for communicating back and forth between the two boards and 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. 
         [0033]    The cooler base  700  preferably contains electrical circuitry to communicate various attributes of the cooler to the board  116 . The cooler attributes that can be communicated include, but are not limited to: evaporator temperature, cooler temperature, door open/close status, energy saving mode status, compressor status, evaporator fan status, and defrost status. The board  116  can then transmit the cooler attributes to a remote user through the modem. The board  116  can also record and transmit various attributes of the board  116  as well as the media player. These attributes can include but are not limited to: video input status, video resolution, voltage/current, and board temperature. 
         [0034]    The board  116  can also communicate several alarm conditions, including but not limited to: temperature sensor failures, receiver board  117  communication failures, invalid defrost temperature, defrost timeout, missed defrost cycle, high/low temp exceeded, invalid video input, and video input stalled. 
         [0035]    The LEDs  217  may be arranged along the top and bottom edges of the transparent LCD  200 . The LEDs may be electrically connected to the board  116 . 
         [0036]      FIG. 8  is a screen shot of an exemplary user interface for operating a power saving mode. The power saving mode can be ‘enabled’ or ‘disabled.’ The user can select a backlight reduction percent level  1 , which provides the percentage of power reduction to the backlight when level  1  power saving is detected. In this example, the level  1  power reduction is 34% from the normal operation power level. The user can also select how long the door remains closed before initiating level  1  power saving. In this embodiment, level  1  power saving is initiated once the door has been closed for 300 seconds. 
         [0037]    Additionally, the user can select a backlight reduction percent level  2 , which provides the percentage of power reduction to the backlight when level  2  power saving is detected. In this example, the level  2  power reduction is 73% from the normal operation power level. The user can also select how long the door remains closed before initiating level  2  power saving. In this embodiment, level  2  power saving is initiated once the door has been closed for 1800 seconds. 
         [0038]      FIG. 9  is a flow chart for an exemplary logic structure for operating the optional power saving mode. The system first checks the sensor  600  to determine if the door is open. If yes, the current time is stored as the Previous Opening time (PO) and the backlight is driven at full power. If the door is closed, the present time is compared to the PO to determine how much time has elapsed since the previous door opening. The elapsed time may then be compared against predetermined time periods. If the time elapsed is not greater than Time Level  1  (ex. 300 seconds), the backlight continues to be driven at full power. If the time elapsed is greater than Time Level  1 , the system moves on to compare the time elapsed with Time Level  2  (ex. 1800 seconds). If the time elapsed is less than Time Level  2 , the backlight is driven at reduced level  1  (ex. 34% of full power). If the time elapsed is greater than Time Level  2 , the backlight is driven at reduced level  2  (ex. 73% of full power). 
         [0039]      FIG. 10  is a flow chart for another exemplary logic structure for operating the optional power saving mode. The system preferably begins by driving the backlight at full power. Next, the sensor  600  is checked to determine if the door has gone from opened to closed. If not, the system continues to drive the backlight at full power and continues to monitor the sensor  600 . If yes, the current time is stored as the Previous Opening time (PO) and the logic moves forward to determine how much time has elapsed since the PO. If the time elapsed is less than Time Level  1 , the door sensor  600  is again checked and if the door is still closed the system will return to measure the elapsed time since the PO, if however the door has been opened the system will return to the start where the backlight is driven at full power. 
         [0040]    If the time elapsed is greater than Time Level  1 , the system then preferably compares the elapsed time since the PO and compares it to Time Level  2 . If the elapsed time is less than Time Level  2 , the backlight is preferably driven at Reduced Level  1 . If the elapsed time is greater than Time Level  2 , the backlight is preferably driven at Reduced Level  2 . In either scenario the system will preferably again check the sensor  600  and if the door has been opened the system will return to the start where the backlight is driven at full power. If however the door remains closed, the system will preferably return to the logic step of comparing the elapsed time since the PO with Time Level  1 . 
         [0041]      FIG. 11  is an electrical schematic representation of an exemplary embodiment of the system for tracking and analyzing display case usage. Here, a plurality of display cases  50  are in communication with an internet/cellular network  70 . Here, an operations center contains at least one CPU  40  which can communicate with the plurality of display cases  50  through the internet/cellular network  70 . 
         [0042]    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. 
         [0043]    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.

Technology Classification (CPC): 8