Abstract:
A system for controlling the transparency of a display case having a door is disclosed. A transparent electronic display is positioned within the door, a controller is electrically connected to the electronic display and configured to track the present time, a network connectivity device is in electrical connection with the controller and communication with a communications network, and a remotely located user interface receives user input through the communications network. The user input is used to generate the transparency data, which is used by the controller to drive the electronic display at various transparency levels.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. Non-Provisional application Ser. No. 14/882,021 filed Oct. 13, 2015, which claims the priority of U.S. Provisional Application No. 62/064,304 filed Oct. 15, 2014. The disclosures of each of which are hereby incorporated by reference in their entireties. 
     
    
     TECHNICAL FIELD 
       [0002]    Embodiments generally relate to systems for tracking and analyzing the use of 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 refrigerated or non-refrigerated and may be placed in grocery stores, convenience stores, gas stations, restaurants, stadiums, race tracks, bakery, deli, hotels, or other retail establishments. It is desirable to place the products within a transparent housing, so that the customer can view them and hopefully make a purchase. 
         [0004]    However, it has been discovered that exposure to light, or more generally electromagnetic radiation, both visible and invisible can cause a product to degrade. In some instances, the product may be an organic product where exposure to various wavelengths of radiation may cause the proteins or other components to break down. In other instances, the products may be inorganic but may contain materials (ex. plastics) which may degrade from exposure to various wavelengths of radiation. While it is desirable to offer the products in transparent cases, the exposure to radiation is undesirable as it will limit the shelf life of the product. 
       SUMMARY OF THE EXEMPLARY EMBODIMENTS 
       [0005]    An exemplary embodiment replaces at least one side of a display case with a liquid crystal display (LCD). In some embodiments, the lighting for the display case can be provided entirely within a front glass assembly which also contains the LCD. Preferably, the LCD is a normally-black LCD which can be described as an LCD which is opaque or black when voltage is not applied to the pixel electrodes. However, some embodiments of the invention may be practiced with a normally white LCD. 
         [0006]    In one embodiment, the LCD can be used in a simple on/off manner, where the LCD is made transparent during open retail hours but is then made opaque during after-hours. When using a normally black LCD, the subpixels may be driven at a high voltage during retail hours but then completely turned off during after-hours. 
         [0007]    In another embodiment, the transparency of the LCD may be varied depending on the time of day, feedback from an ambient light sensor, presence of a consumer, or the activity of a display case door opening/closing. During times of non-use, the LCD can be turned off so that when using a normally black LCD the products will be shielded from various wavelengths of radiation, extending their shelf life. 
         [0008]    In another embodiment, the lighting for the display case as well as the LCD may be embedded within a front glass unit where the amount of lighting can also be varied in addition to the transparency of the LCD. 
         [0009]    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 
         [0010]    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: 
           [0011]      FIG. 1  is a perspective view of a refrigerated display case having a LCD assembly. 
           [0012]      FIG. 2  is a perspective view of the refrigerated display case of  FIG. 1  where the door has been opened. 
           [0013]      FIG. 3  is a simplified side view of the various layers within an exemplary front window assembly. 
           [0014]      FIG. 4  is an electrical block diagram for an exemplary embodiment. 
           [0015]      FIG. 5  is a flow chart for a first embodiment for operating the method to prevent damage to products. 
           [0016]      FIG. 6  is a screen shot of an exemplary user interface for operating a method for preventing damage to products when using an optional LED backlight with the LCD. 
           [0017]      FIG. 7  is a flow chart for an exemplary logic structure for operating one embodiment of the product protect mode. 
           [0018]      FIG. 8  is a flow chart for another exemplary logic structure for operating one embodiment of the product protect mode. 
           [0019]      FIG. 9  is an electrical schematic representation of an exemplary embodiment of the system for preventing damage to products. 
       
    
    
     DETAILED DESCRIPTION 
       [0020]    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. 
         [0021]    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. 
         [0022]    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. 
         [0023]    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. 
         [0024]      FIG. 1  is a perspective view of a refrigerated display case  50  having a LCD  200 . Generally, the display case includes a housing  105 , to which a front window assembly  100  is fastened. In this embodiment, a cavity  110  is provided below the front window assembly  100  where various electronic devices  111  for operating the LCD assembly  200  can be located. 
         [0025]      FIG. 2  is a perspective view of the refrigerated display case of  FIG. 1  where the door has been opened. In this embodiment, the front window assembly  100  is hingedly fastened to the housing  105 , although this is not required. The 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. 
         [0026]    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 3MTM of St. Paul, Minn. www.3M.com/converter. In order to illuminate the 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. 
         [0027]      FIG. 3  is a simplified side view of the various layers within an exemplary front window assembly  100 . Various electronic components  400  for operating the LCD  200  and communicating with the front window assembly  100  can be placed within the sealed assembly. In some embodiments, the electronic components  400  can be mounted to the front glass  225  or the rear glass  205 . A light guide  300  and the LCD  200  are preferably sealed between the front glass  225  and rear glass  205 . The sealed enclosure is preferably filled with argon gas. A plurality of LEDs  350  may be arranged along opposing edges of the light guide  300 . In an exemplary embodiment, an optional additional linear polarizer  375  is positioned behind the light guide  300 . The optional additional linear polarizer  375  could be attached to the rear surface of the light guide  300 , front surface of the rear glass  205 , or the rear surface of the rear glass  205 . As noted above, the LCD  200  is preferably a normally-black LCD. 
         [0028]      FIG. 4  is a block diagram for an exemplary embodiment of the electronic components  400  within the front window assembly as well as the electronic components  111  in the cavity  110  below the front window assembly. 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. 
         [0029]    The 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. 
         [0030]    The board  116  and the receiver board  117  each preferably contain a microprocessor and a storage device (RAM). 
         [0031]    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. 
         [0032]    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. 
         [0033]    Also shown in this figure is the temperature sensor  620  which is in electrical communication with the electronic devices  111 . Also shown here is a door sensor  600  which is positioned to determine whether the front window assembly is currently open or not (if using a hinging front window assembly  100 ). 
         [0034]    A timing and control board (TCON)  420  is shown in electrical communication with the receiver board  117  and the LCD  200 . It should be noted that the LEDs  350  are not required, as some embodiments may utilize ambient lighting or lighting within the display case to backlight the LCD  200 . 
         [0035]    The LCD  200  may operate various pixels by applying a voltage to them. During normal operations, the LCD  200  may display pixels at various transparency levels in order to generate colored pixels that assemble to display a graphic. In exemplary embodiments, the modem may receive transparency data that is transmitted to the LCD  200  by way of the board  116 . The transparency data may include data that instructs the LCD  200  to drive each pixel at substantially the same transparency level. An exemplary embodiment of the method for preventing damages to the products of the display case  50  may include the step of operating each sub-pixel of the LCD  200  at a predetermined uniform transparency level by way of the controller and according to the transparency data. In other words, in some embodiments, each sub-pixel of the LCD  200  is generally driven to substantially the same level of transparency (sometimes this means applying the same sub-pixel voltages to each sub-pixel). 
         [0036]      FIG. 5  is a flow chart for a first embodiment for operating the method to prevent damage to products. A user may input a schedule for the retail hours and the after hours. This schedule can be accepted and stored in a number of ways. The schedule can be a weekly hour-by-hour schedule, which is uploaded only once and gives the schedule for Monday-Sunday to be performed by the software every week. In other embodiments, the schedule may be a daily schedule, which is uploaded for a single  24  hour period and is repeated for every single day. In other embodiments, the schedule may be a full calendar with daily specifics as to what the retail hours and the after hours will be specifically for each day. Other embodiments may have the system simply presume retail hours and only accept after hours data for each specific day, weekly schedule, or daily schedule. 
         [0037]    In some embodiments, during retail hours the LCD  200  is simply controlled to be substantially transparent, i.e. enough voltage is sent from the TCON  420  to the LCD  200  to obtain a desired level of transparency. In other embodiments, during retail hours the LCD  200  may be driven as transparent and may also contain images and advertisements, sent from the media player to the board  116  and ultimately to the TCON  420 . The images and advertisements can be transmitted to the media player from the board  116 , after being received at the modem. 
         [0038]    The user may communicate the various retail and after hours data to the board  116  in a number of ways. First, the user can physically connect to the modem  115  (using a cable, ex. Ethernet/DSL cable). Second, the user can communicate though the modem  115  by using any internet connection with a remote device. Third, the user can communicate through the modem  115  by using cellular antennas  115  (shown in electrical communication with the modem  115 ) and a cellular device. The logic is preferably operated by the microprocessor located on the board  116 . 
         [0039]      FIG. 6  is a screen shot of an exemplary user interface for operating a method for preventing damage to products when using an optional LED  350  backlight with the LCD  200 . The product protection 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%. 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. 
         [0040]    Optionally, the user can select a number of backlight reduction levels. Here, the embodiment permits the selection of 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%. 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. 
         [0041]    In this embodiment, the user can also select how long the door should be closed before the LCD is turned off to protect the products (shown in this Figure as Level  3 ). Here, the LCD would be turned off with no power sent to the TCON  420  once the door has been closed for 3600 seconds. 
         [0042]      FIG. 7  is a flow chart for an exemplary logic structure for operating the optional product protect 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. 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 system moves on to compare the time elapsed with Time Level  3  (ex. 3600 seconds). If the time elapsed is less than Time Level  3 , the backlight is driven at reduced level  2  (ex. 73% of full power). If the time elapsed is greater than Time Level  3 , the LCD is turned off (ex. no power is sent to the TCON  420 ). 
         [0043]      FIG. 8  is a flow chart for another exemplary logic structure for operating the optional product protect 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. 
         [0044]    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 system preferably then compares the elapsed time since the PO and compares it to Time Level  3 . If the elapsed time is less than Time Level  3 , the backlight is preferably driven at Reduced Level  2 . If the elapsed time is greater than Time Level  3 , the LCD is turned off. 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 . 
         [0045]      FIG. 9  is an electrical schematic representation of an exemplary embodiment of the system for preventing damage to products. 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 . 
         [0046]    The embodiments of the wireless communication and 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. 
         [0047]    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.