Abstract:
A simplified touch screen system that can sense when an object is held in continuous direct or indirect contact with a transparent substrate of the touch screen system as well as determine a location (e.g., X, Y coordinates) of the object in relation to the transparent substrate. The touch screen system employs capacitance technology to sense whether the object is held in contact with the transparent substrate and acoustic sensing technology to determine a position of the object that is contacting the transparent substrate. The touch screen system requires a reduced number of shielding and isolation layers to be deposited upon the transparent substrate, partially because the touch screen system utilizes a bezel associated with an underlying display to provide shielding against electromagnetic radiation emitted by the display.

Description:
BACKGROUND 
       [0001]    A variety of electronic devices employ touch screens or touch panels to detect the presence and location of a touch within a display area of the electronic device, generally by a finger, hand, or other object. Such electronic devices include mobile phones, internet devices, portable game consoles, portable readers, music players, navigation devices, appliances, automation and control electronics, laptop computers, television screens, and the like. Touch screens allow for direct interaction with what is displayed on the screen where it is displayed, rather than indirect interaction through a mouse or separate touch pad. Touch screens also enable such interaction without requiring any intermediate devices, such as a stylus that must be held in a user&#39;s hand. 
         [0002]    There are a number of touch screen technologies, and from among these various technologies, acoustic touch screen technology has emerged as a durable and accurate technology that functions even when the screen itself is dirty or scratched. Acoustic touch screen technology involves using acoustic transducers to convert the mechanical or acoustic energy generated by a physical contact with a touch screen substrate into an electronic signal. Hardware and software that is operatively connected to the transducers then analyzes the electronic signal to determine the location of the contact. Because no acoustic energy is generated when the finger or other object lies motionless against the screen, acoustic sensing technology is unable to detect when a finger is held against the screen after an initial contact. 
         [0003]    One proposed solution to this problem includes a capacitive sensing mechanism that employs conductive wire to connect a number of capacitors in series along one or more borders of the touch screen substrate. Each of the capacitors includes two electrodes that are spaced a distance apart. When a user touches a surface of the screen substrate with an object such as a finger, the electrodes to move towards one another, thereby reducing the gap between the electrodes and causing a capacitance variation that can be converted into a binary signal representing a “hold” or “release” action in relation to a contact with the touch screen. Further, to shield against electromagnetic interference from both the environment and an associated display, known touch screen systems employ a number of conductive and insulating layers deposited upon the screen substrate. 
         [0004]    While the existing approach allows the touch screen system to sense when an object is in continuous contact with the screen, it has many shortcomings. For instance, using soldered wires to interconnect the capacitors in series is a time-consuming manual process that introduces variance into the system and reduces the quality and reliability of the hold-and-release sensing. In addition, depositing numerous conductive and insulating layers onto the screen substrate to adequately shield against noise caused by electromagnetic radiation consumes a great deal of material, much of which is lost during the printing process, rendering the manufacturing process unduly wasteful and expensive. Further, existing acoustic and capacitive touch screen systems have required dedicated connectors to link both the acoustic and the capacitive sensing components on the screen substrate with the processing components on an associated control board. These dual connectors enlarge the space required for the touch screen system and render the system too bulky for many compact electronic devices. 
         [0005]    It is against this background that the teachings herein have been developed. 
       SUMMARY 
       [0006]    Disclosed herein is a touch screen system for an electronic device having a power source and a touch screen control board. The touch screen system includes a transparent substrate having an external surface and an internal surface, the transparent substrate for receiving a contact from an object upon the external surface; deposited layers arranged about a perimeter of the internal surface of the transparent substrate, the deposited layers consisting of a conductive layer deposited upon the internal surface of the transparent substrate, where the conductive layer forms a pattern of conductive traces, and an isolation layer deposited upon the conductive layer; one or more acoustic sensors associated with the transparent substrate, where the acoustic sensors receive an acoustic wave generated by the contact and convert the acoustic wave to an electronic signal, and where the acoustic sensors are electrically connected through a first one of the conductive traces; and a plurality of capacitive sensors associated with the transparent substrate, each of the capacitive sensors comprising a first electrode that is spaced a distance from a second electrode, where each of the first electrodes is both formed by and electrically connected through a second one of the conductive traces and each of the second electrodes is electrically connected through a third one of the conductive traces, and where the contact of the object causes a capacitive change in the capacitive sensors. 
         [0007]    The touch screen system may further include a processor for monitoring the electronic signal and the capacitive change. The processor may analyze the electronic signal to determine a location of the object upon the transparent substrate and monitor the capacitive change to determine whether the object remains in continuous contact with the transparent substrate. The system may also include one flexible printed circuit (FPC) connector that electrically connects each of the conductive traces with the touch screen board. Moreover, the touch screen system may further include a compressible gasket situated between the first and second electrodes of each of the capacitive sensors. The compressible gasket may be formed of a double-sided foam tape. 
         [0008]    One of the capacitive sensors may be positioned at an approximate middle point along each edge of the internal surface of the transparent substrate. Each of the second electrodes may include a first electrically conductive area deposited upon a first side of an FPC strip. The FPC strip may include a second side having a second electrically conductive area, and the second electrically conductive area may be grounded through a fourth one of the conductive traces such that the second electrically conductive area provides electromagnetic radiation shielding. The object may be a finger, and the acoustic wave may be a bending wave. 
         [0009]    The touch screen system may further include a display having an active display area and a conductive bezel framing a perimeter of the active display area. The conductive bezel may shield the acoustic sensors, the capacitive sensors, and the conductive traces from electromagnetic radiation emitted from the display. 
         [0010]    Also disclosed is a method of analyzing a contact from an object upon a touch screen system. The method includes providing a transparent substrate having external and internal surfaces; depositing layers, other than shielding layers, on the internal surface of the transparent substrate, the depositing including depositing a layer of conductive material to form an annular pattern of conductive traces about a perimeter of the internal surface of the transparent substrate, where the conductive traces form a plurality of first electrodes, and depositing a layer of insulating material upon the layer of conductive material; connecting a plurality of second electrodes to the conductive traces, where each of the second electrodes is spaced a distance from one of the first electrodes such that each pair of the first and the second electrodes forms a capacitive sensor, and wherein the contact of the object causes a capacitive change in the capacitive sensors; and connecting one or more acoustic sensors to the conductive traces, wherein the acoustic sensors receive an acoustic wave generated by the contact from the object and convert the acoustic wave to an electronic signal. 
         [0011]    The method may further include associating a processor with the conductive traces and, upon the contact of the object with the external surface of the transparent substrate, using the processor to monitor the electronic signal to determine a location of the object upon the transparent substrate and to monitor the capacitive change to determine whether the object remains in continuous contact with the transparent substrate. 
         [0012]    Each of the second electrodes may include a first electrically conductive area deposited upon a first side of an FPC strip. The FPC strip may include a second side having a second electrically conductive area, and the method may further include grounding the second electrically conductive area through the conductive traces such that the second electrically conductive area provides electromagnetic radiation shielding. 
         [0013]    The method may further include associating a display and a conductive bezel with the transparent substrate, where the display has an active display area and the conductive bezel frames a perimeter of the active display area such that the bezel aligns with the layer of conductive material, and grounding the conductive bezel such that the bezel shields the acoustic sensors, the capacitive sensors, and the conductive traces from electromagnetic radiation emitted from the display. The grounding may include connecting the bezel to ground through the conductive traces. The method may also include connecting each of the conductive traces to a touch screen control board through an FPC connector. 
         [0014]    Also disclosed is a touch screen system for an electronic device having a power source and a touch screen control board. The touch screen system includes a transparent substrate having an external surface and an internal surface, the transparent substrate for receiving a contact from an object upon the external surface; a pattern of conductive traces arranged about a perimeter of the internal surface of the transparent substrate, where the conductive traces are deposited directly upon the internal surface of the transparent substrate; one or more acoustic sensors associated with the transparent substrate, where the acoustic sensors receive an acoustic wave generated by the contact and convert the acoustic wave to an electronic signal, and where the acoustic sensors are electrically connected through a first one of the conductive traces; and a plurality of capacitive sensors associated with the transparent substrate, each of the capacitive sensors comprising a first electrode that is spaced a distance from a second electrode, wherein each of the first electrodes is both formed by and electrically connected through a second one of the conductive traces and each of the second electrodes is electrically connected through a third one of the conductive traces, and where the contact of the object causes a capacitive change in the capacitive sensors. 
         [0015]    The touch screen system may further include an isolation layer deposited upon the conductive traces, a display having an active display area, and a conductive bezel that frames a perimeter of the active display area. The conductive bezel may substantially abut the isolation layer and may be connected to ground. 
         [0016]    The touch screen system may further include one FPC connector that electrically interconnects each of the conductive traces with the touch screen control board. Further, the touch screen system may include a processor for monitoring the electronic signal and the capacitive change. The processor may analyze the electronic signal to determine a location of the object upon the transparent substrate and the capacitive change to determine whether the object remains in continuous contact with the transparent substrate. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]      FIG. 1A  shows an exploded bottom perspective view of one embodiment of a touch screen assembly as electrically interconnected to a touch screen control board via a flexible printed circuit connector. 
           [0018]      FIG. 1B  shows a perspective view of a first side of a flexible printed circuit band for inclusion in the touch screen assembly of  FIG. 1A . 
           [0019]      FIG. 1C  shows a perspective view of a second side of a flexible printed circuit band for inclusion in the touch screen assembly of  FIG. 1A . 
           [0020]      FIG. 2  shows a top view of several conductive traces as deposited on an internal surface of a transparent substrate included in the touch screen assembly of  FIG. 1A . 
           [0021]      FIG. 3  shows an exploded top perspective view of the touch screen assembly of  FIG. 1A  as disposed above one embodiment of an associated display and bezel. 
           [0022]      FIG. 4  shows a functional diagram of the touch screen control board of  FIG. 1A . 
           [0023]      FIG. 5A  shows a functional diagram of a transparent substrate included in the touch screen assembly of  FIG. 1A . 
           [0024]      FIG. 5B  shows several acoustic signatures that correspond to exemplary points of impact upon the transparent substrate shown in  FIG. 5A . 
       
    
    
     DETAILED DESCRIPTION 
       [0025]    While the embodiments of the invention are susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the description is not intended to limit the invention to the particular form disclosed, but rather, the invention is to cover all modifications, equivalents, and alternatives of embodiments of the invention as defined by the claims. 
         [0026]    As discussed above, acoustic touch screen technology excels in detecting a location at which an object contacts a touch screen substrate (hereinafter “position sensing”) but is generally unable to sense whether the object remains in continuous contact with the substrate, or whether the object is being held against the substrate (hereinafter “hold-and-release sensing”). To remedy this problem, a simplified capacitance sensing structure has been combined with acoustic sensing technology to create a touch screen system that achieves both effective hold-and-release sensing and position sensing in an elegant design that may be manufactured according to a simplified manufacturing process. 
         [0027]      FIG. 1A  shows an exploded view of one embodiment of a touch screen assembly  10  as electrically interconnected to a touch screen control board  50  having various electronic components that will be described in detail below. In this embodiment, the touch screen assembly  10  includes a transparent substrate  12  having top, bottom, left, and right edges  14 ,  16 ,  18 , and  20 , respectively. The transparent substrate  12  also has an external surface  22  that receives a contact of an object  44  (e.g., a finger, a stylus, a pen, a credit card, etc.) and an internal surface  24 , which lies adjacent to an interior of an associated electronic device (not shown) such as, for instance, a mobile phone, a portable display, an electronic book, a laptop, a television, an automotive display, or the like. The transparent substrate  12  may be formed of any appropriate transparent material including, for example, glass or plastic. 
         [0028]    A number of conductive traces  26   1-4  may be deposited in an annular arrangement about a perimeter of the internal surface  24  of the transparent substrate  12 . The conductive traces  26   1-4  may be printed or otherwise deposited directly onto the interior surface of the transparent substrate  12  and may be formed of any appropriate conductive material such as, for example, silver.  FIG. 2  shows a detailed schematic of the placement of each of the conductive traces  26   1-4  upon the internal surface  24  of the transparent substrate  12 . The traces  26   1-4  are electrically connected to the touch screen control board  50  via a single connector  46 . The connector  46  may be any appropriate connector and, in one embodiment, the connector  46  is a flexible printed circuit (FPC) connector that is configured to receive inputs from each of the conductive traces  26   1-4 . 
         [0029]    While the functionality of each of the traces  26   1-4  will be explained in greater detail below, it should be noted that each of the conductive traces  26   1-3  is a pair of conductive traces. That is, as shown in  FIGS. 1A and 2 , a trace or traces from each pair of conductive traces  26   1-3  is deposited along the top and left edges  14 ,  18  of the interior surface  24  of the transparent substrate  12 , and another trace or traces from each pair of conductive traces  26   1-3  is deposited along the bottom, left, and/or right edges  16 ,  18 ,  20  of the interior surface  24  of the transparent substrate  12 . 
         [0030]    An insulating or isolation layer  38  may be deposited as an annular structure that lies directly upon the conductive traces  26   1-4 . The isolation layer  38  may be formed of any appropriate electrically insulating material such as, for example, polyvinylchloride or an electrically insulating tape. 
         [0031]    To achieve accurate position sensing as discussed above, acoustic sensors or transducers  42  may be positioned along one or more edges  14 ,  16 ,  18 , and  20  of the transparent substrate  12  such that the acoustic transducers  42  are in electrical contact with a pair of first conductive traces  26   1  ( FIG. 2 ). For instance, in this embodiment, the acoustic transducers  42  are positioned along the top edge  14  and the left edge  18  of the transparent substrate. When an object  44  contacts the external surface  22  of the transparent substrate  12 , the impact generates an acoustic or bending (i.e., mechanical) wave that propagates through the transparent substrate  12  to be received at the acoustic transducers  42 . The acoustic transducers  42  may be piezoelectric crystals or any other acoustic transducers of any appropriate size, shape, type, and/or configuration. While the acoustic transducers  42  are aligned with the top and left edges  14  and  18  of the transparent substrate  12  in this embodiment, the acoustic transducers  42  may be placed at any appropriate position(s) relative to the transparent substrate  12 . 
         [0032]    Upon a contact of an object  44  against the external surface  22  of the transparent substrate  12 , a resulting bending wave propagates through the substrate  12  and is received at the acoustic transducers  42 . The acoustic transducers  42  convert the bending wave to an analog electronic signal, which may be transmitted from the acoustic transducers  42 , along the first conductive traces  26   1 , and to the touch screen control board  50  via the connector  46  for processing to determine a location (e.g., X, Y coordinates) of the contact of the object  44  against the external surface  22  of the transparent substrate  12 . Details relating to position sensing processing will be discussed below with reference to  FIG. 4 . 
         [0033]    Because only an initial contact or a subsequent movement creates acoustic or bending waves that propagate through the transparent substrate  12 , the acoustic sensors  42  are not sufficient to detect a “hold” that occurs when the object  44  is held in continuous contact with the substrate  12 . Thus, one embodiment of the touch screen assembly  10  also includes four simplified capacitive sensors positioned along the top, bottom, left, and right edges  14 ,  16 ,  18 , and  20  of the internal surface  24  of the transparent substrate  12 . Each capacitive sensor is formed from a first electrode  28  that is spaced apart from a second electrode  34  ( FIG. 1B ) that is formed on strip or band  30  of FPC material such as, for example, a polyimide substrate or base. 
         [0034]    In further detail and as shown in  FIG. 1A , each of the first electrodes  28  is incorporated within a pattern of a second conductive trace  26   2  that is deposited upon the internal surface  24  of the transparent substrate  12 . As shown in  FIG. 1B , each of the second electrodes  34  is formed on the FPC band  30 . More specifically, a first side  36  of the FPC band  30  may be coated with a conductive material such as copper. Each of the FPC bands  30  may be assembled into the touch screen assembly  10  such that the first side  36  faces the first electrode  28  and is electrically connected to a third conductive trace  26   3  ( FIG. 2 ) through an access aperture  48  in the isolating layer  38 . As a result, the conductive material on the first side  36  of the FPC band  30  forms a second electrode  34 , and each pair of the first and second electrodes  28  and  34  combines to form a capacitive sensor. 
         [0035]    In this embodiment, each of the first electrodes  28  and the second electrodes  34  may be separated by the isolating layer  38  as well as one or more flexible gaskets  40 . The flexible gaskets  40  may be formed of an insulating material having any appropriate size, shape, type, and/or configuration. In one embodiment, the flexible gaskets  40  may be formed from double sided foam tape having approximate length, width, and thickness dimensions of 0.6 mm×0.6 mm×0.15 mm. 
         [0036]    The touch screen assembly  10  may be positioned above a display  52 , as shown in  FIG. 3 . The display  52  may be any of several types of displays, including DLP® displays, LCOS displays, TFT displays, other LC display types and/or brands, OLED displays, or any other suitable display types. The display  52  may have an active display area  54  with which a user may indirectly interact using the object  44 , as discussed above. Thus, because the display  52  lies below the touch screen assembly  10 , any portions of the touch screen assembly  10  that directly overlay the active display area  54  of the display  52  are preferably transparent so as to allow a user to see through the assembly  10  to the active display area  54 . 
         [0037]    The display  52  may include a bezel  56  that frames the active display area  52 . The bezel may be formed of any appropriate conductive material such as aluminum or another appropriate metal. To shield the electronic components of the touch screen assembly  10  (e.g., the conductive traces  26   1-4 , the first and second electrodes  28 ,  34 , the acoustic transducers  42 ) from electromagnetic radiation emitted from the display  52 , the display  52  may be connected to ground  58  on the touch screen control board  50  ( FIG. 4 ). For instance, the bezel  56  may be electrically connected to ground  58  through a fourth conductive trace  26   4  ( FIG. 2 ). In this regard, the bezel  56  negates any need to deposit additional shielding layers between the isolation layer  38  and the display  52  to protect against electromagnetic interference caused by the display. As a result, when the display  52  and the bezel  56  are disposed below the touch screen assembly  10 , the bezel  56  may substantially abut the isolation layer  38 , as shown in  FIG. 3 . 
         [0038]    In addition, as shown in  FIG. 1C , a second side  37  of the FPC band  30 , discussed above, may also be coated with conductive material (e.g., copper) and be connected to ground  58  ( FIG. 4 ) in any appropriate manner, thereby forming a grounding plate  39  that provides additional shielding against electromagnetic radiation emitted from the display  52  in order to achieve more exact hold-and-release sensing between the first and second electrodes  28  and  34 . In one implementation, each of the the grounding plates  39  may be connected to ground  58  ( FIG. 4 ) through the fourth conductive trace  26   4 . A through hole  35  may conduct the grounding plate  39  from the second side  37  of the FPC band  30  to the first side  36  of the FPC band  30 , where it is bonded to the fourth conductive trace  26   4  as accessed through an aperture  49  in the isolation layer  38 . 
         [0039]    In operation, a power supply  60  associated with the touch screen control board  50  ( FIG. 4 ) may apply an analog voltage (which alternatively may be referred to as a stimulus signal) to charge the capacitive sensors. When a user touches the external surface  22  of the transparent substrate  12  with the object  44 , the pressure of the object  44  compresses the flexible gaskets  40 , thereby reducing the distance between the first and second electrodes  28  and  34 . Because the capacitance of each pair of first and second electrodes  28  and  34  is a function of the distance between the first and second electrodes  28  and  34 , this compression causes a measurable capacitance variation, ΔC, within the capacitive sensors. This AC may be detected and converted into a binary signal for a hold or release action at the touch screen control board  50 , and discussed below. 
         [0040]      FIG. 4  shows a functional block diagram of one embodiment of the touch screen control board  50 . In this embodiment, the touch screen control board  50  includes the power supply  60 , which receives power from an external power source (not shown) such as, for example, a battery. The power supply  60  may be coupled with each component on the touch screen control board  50  to provide the desired form of voltage to each component. In addition, one or more of the components may be connected to ground  58 . For ease of illustration, these internal connections are not shown. The touch screen control board  50  also includes a number of additional components for carrying out the control and processing functionality of the touch screen assembly  10 , and it should be noted that any appropriate variation of these individual components and/or the configuration of the components is contemplated. 
         [0041]    With respect to determining a location of the object  44  in contact with the transparent substrate  12 , the electronic signal received at the acoustic transducers  42  may be amplified either at the acoustic transducers  22  or at an amplifier  62  on the touch screen control board  50 . The amplified signal is passed to a front end processor  64 , which may include an analog-to-digital (A/D) converter  66 . The A/D converter  66  digitizes the amplified signal and transmits the digitized data to a microcontroller  68 , which processes the digitized data to determine a location (i.e., X, Y coordinates) of the object  44  relative to the transparent substrate  12 . 
         [0042]    To make this positional determination, the microcontroller  68  accesses a memory  70  and compares the digitized data received from the acoustic transducers  42  with data stored at the memory  70 . The stored data represents a number of unique waves, or signatures, that are generated from impacts at known locations relative to the transparent substrate  12  during the manufacturing process. For example,  FIG. 5A  shows a number of known impact points  72   1-7  relative to the transparent substrate  12 . Contacting the substrate  12  at each of the impact points  72   1-7  produces a number of corresponding wave signatures  74   1-7 , shown in  FIG. 5B . The signatures  74   1-7  and their corresponding X, Y coordinates  72   1-7  are stored in the memory  70  for use by the microcontroller  68  in determining where the object  44  is contacting the external surface  22  of the transparent substrate  12  during use of the touch screen assembly  10 . While  FIG. 5B  shows signatures that correlate with only seven impact points  72   1-7 , any appropriate number of signatures may be stored in the memory  70  (e.g., 1000 points, 4000 points, etc.). Further, if a signature correlating to the impact point is not included in the stored data, the microcontroller  68  may execute an algorithm to extrapolate the location based on the closest impact point that is included in the stored data. Based on this comparison and/or calculation, the microcontroller  68  outputs the X, Y coordinates of the impact point for use in interacting with the display  52  and controlling the electronic device (not shown) as desired by the user. 
         [0043]    The touch screen control board  50  also includes components that process the capacitance change, ΔC, which results when the object  44  contacts the external surface  22  of the transparent substrate  12 . Specifically, a determination is made regarding whether the object  44  is being held in continuous contact with the transparent substrate  12  after the initial contact. In one embodiment, the ΔC may register on a capacitance-to-digital converter (CDC)  76  on the touch screen control board  50 , where the ΔC may be converted to a discrete voltage level. The CDC  76  may be any appropriate CDC, and one suitable example includes the AD7150 capacitance converter from Analog Devices, Inc. The discrete voltage level output from the CDC  76  may correlate with whether or not the object  44  is in contact with the transparent substrate  12 . Further, the discrete voltage level may be routed through the A/D converter  66  of the front end processor  64  for further processing before it is sent to the microcontroller  68 , which may, in turn, execute logic that determines whether the object  44  is in contact with transparent substrate  12  based on the discrete voltage level. For example, the microprocessor  68  may be programmed to determine that the object  44  is contacting the substrate  12  when the discrete voltage level is at or below a predefined voltage V touch  (e.g., 3.3 V) and that the object  44  has been removed from the substrate  12  when the discrete voltage level is above the predefined voltage V touch . 
         [0044]    In an alternative embodiment, the ΔC may register on a resistor-capacitor circuit (RC circuit) (not shown) on the touch screen control board  50 , thereby altering the charge/discharge time, or oscillation frequency, of the RC circuit. The voltage output from the RC circuit may be passed to the A/D converter  66 , which monitors the change in output voltage versus time in order to track the oscillation frequency of the RC circuit. The microcontroller  68  may then use the output from the A/D converter  66  to recognize a hold and release action, or whether the object  44  is in contact with the external surface  22  of the transparent substrate  12 . 
         [0045]    Using this capacitive sensing technology in combination with the acoustic sensing technology described above allows the touch screen assembly  10  to not only determine the location of an object that contacts the transparent substrate  12  but also whether the object is held against the substrate  12  for a period of time. This is accomplished without connecting the capacitive sensors using soldered conductive wire and without the need for printed or deposited shielding layers upon the transparent substrate  12 , thereby reducing the time, complexity, and expense associated with manufacturing the touch screen assembly  10  and increasing the accuracy and reliability of the hold-and-release sensing mechanism of the system. Furthermore, the acoustic sensing and hold-and-release sensing components of the touch screen assembly  10  are transmitted to the touch screen control board  50  via a single connector  46 , thereby reducing the footprint associated with the mechanical design and making the touch screen assembly  10  feasible for increasingly smaller electronic devices. 
         [0046]    While the embodiments of the invention have been illustrated and described in detail in the drawings and foregoing description, such illustration and description is to be considered as examples and not restrictive in character. For example, certain embodiments described hereinabove may be combinable with other described embodiments and/or arranged in other ways (e.g., process elements may be performed in other sequences). Accordingly, it should be understood that only example embodiments and variants thereof have been shown and described.