Patent Publication Number: US-2022221683-A1

Title: Optical assemblies and methods of forming the same with light-curable adhesive

Description:
BACKGROUND 
     Imaging devices (e.g., a camera) capture images of objects within a given field of view (FOV). It is often required that machine vision devices, barcode readers, etc. capture images with resolution sufficient at suitable distances for effective decoding of indicia captured in an image for use in, e.g., machine vision applications, barcode decoding, etc. 
     Capturing a clear, undistorted image requires an image device (e.g., a camera) with a carefully assembled and aligned lens assembly and image sensor. The lens assembly and image sensor need to be carefully aligned so the focus of the optical path of the lens assembly is centered on and perpendicular to the image sensor. For cameras with a fixed lens assembly, these alignments can take place during manufacturing and assembly, where production equipment can be set up to meet design specifications. However, in practice, high-volume manufacturing processes aren&#39;t perfect and can result in out of specification cameras, thereby resulting in expensive scrap or, worse, an unhappy customer. 
     SUMMARY 
     Active alignment processes may be used, during manufacture, to dynamically adjust lens assembly and image sensor positioning based on actual camera performance. Images are captured by the image sensor while the position of the lens assembly is dynamically adjusted relative to the image sensor (e.g., in five or six degrees of freedom) until captured images reflect an intended optical alignment of the lens assembly and image sensor. An adhesive is used to hold the lens assembly in this aligned position relative to the image sensor. 
     Conventionally, the lens assembly holder that holds a lens assembly in alignment with an image sensor is made of an opaque material to help prevent extraneous light from reaching the image sensor. However, because the lens assembly holder is opaque, the adhesive used to hold the lens assembly holder and the lens assembly it holds in alignment with the image sensor is shadowed by the lens assembly holder. Accordingly, the adhesive cannot be fully cured with light. Therefore, light can only be used to temporarily tack cure the lens assembly holder in place, and substantially full curing of the adhesive with heat is required. Thus, an oven is required to cure the adhesive. However, the use of an oven to cure the adhesive can, for example, be expensive, consume a lot of assembly line floor space, slow and/or disruptive to the continuous flow normally found on an assembly line, especially for larger products. 
     Thus, there is a need for optical assemblies and methods of forming the same with light-curable adhesive. Accordingly, the present application discloses lens assembly holders formed of a light transmissive material (e.g., material through which light can pass substantially unimpeded) such that the adhesive is no longer shadowed by the lens assembly holder. Therefore, the lens assembly holder does not prevent light from reaching the adhesive. Thus, the adhesive can be light-curable adhesive, i.e., the adhesive can be substantially cured with just light (e.g., UV light). However, because disclosed lens assembly holders are made of a light transmissive material they may allow extraneous light to reach the image sensor. Thus, in disclosed examples, a light baffle made of an opaque material may be used to seal against the end of the lens assembly to help prevent extraneous light from reaching the image sensor via the end of the lens assembly. Because, in disclosed examples, the bead of the adhesive can be substantially cured with light, the use of ovens, their associated costs, operating expenses, their footprint on assembly lines, their associated additional manufacturing steps, etc. can be eliminated. 
     In an embodiment, a method of assembling an optical assembly may include coupling a lens assembly with a lens assembly holder to form a lens sub-assembly, and applying a light-curable adhesive to a lens chassis fixedly mounted to a printed circuit board (PCB). The method may include optically aligning the lens sub-assembly with an image sensor fixedly mounted to the PCB. When optical alignment is complete, the method may include substantially curing the adhesive with light to fixedly mount the lens sub-assembly to the lens chassis to hold the lens assembly in a fixed optical alignment with the image sensor. 
     In one or more variations of the current embodiment, the lens assembly holder is formed of a light transmissive material, and the method may further comprise passing light external to the lens assembly holder through the lens assembly holder after the optical alignment is complete to cure the light-curable adhesive. 
     In one or more variations of the current embodiment, the light is an ultraviolet light and the lens assembly holder is formed of an ultraviolet light transmissive plastic material. 
     In one or more variations of the current embodiment, coupling the lens assembly with the lens assembly holder may include press fitting the lens assembly at least partially into the lens assembly holder. 
     In one or more variations of the current embodiment, coupling the lens assembly with the lens assembly holder may include threadably inserting the lens assembly at least partially into the lens assembly holder. 
     In one or more variations of the current embodiment, coupling the lens assembly with the lens assembly holder may include adhering the lens assembly to the lens assembly holder. 
     In one or more variations of the current embodiment, the method may further comprise soldering the image sensor to the PCB, mounting a light baffle to the PCB around the image sensor, and fixedly mounting the lens chassis to the PCB around the light baffle. 
     In one or more variations of the current embodiment, an end of the light baffle opposite the image sensor may seal against an end the lens sub-assembly. 
     In one or more variations of the current embodiment, the method may further comprise soldering a controller to the PCB, wherein the controller may be configured to decode indicia captured in images formed at the image sensor and convey decoded indicia payloads to a host system. 
     In another embodiment, an assembly includes an optical assembly that includes a lens chassis fixedly mounted to a printed circuit board (PCB), and an image sensor fixedly mounted to the PCB. The optical assembly may include a lens sub-assembly including a light transmissive lens assembly holder mated with a lens assembly. The optical assembly may include a substantially light-curable adhesive between a surface of the lens chassis and the lens sub-assembly to hold the lens assembly in a fixed optical alignment with the image sensor. 
     In one or more variations of the current embodiment, the assembly further comprises a housing. The optical assembly may be positioned at least partially within the housing. The assembly may include a barcode decoder disposed in the housing and configured to decode indicia captured in images formed at the image sensor. 
     In one or more variations of the current embodiment, the assembly may comprise a barcode reader. 
     In one or more variations of the current embodiment, the lens assembly holder may be formed of a light transmissive material configured to pass light external to the lens assembly holder through the lens assembly holder to cure the light-curable adhesive. 
     In one or more variations of the current embodiment, the light may be ultraviolet light and the lens assembly holder may be formed of an ultraviolet light transmissive plastic material. 
     In one or more variations of the current embodiment, the lens assembly may be press fit at least partially into the lens assembly holder. 
     In one or more variations of the current embodiment, the lens assembly may be threaded at least partially into the lens assembly holder. 
     In one or more variations of the current embodiment, the lens assembly may be adhered to the lens assembly holder. 
     In one or more variations of the current embodiment, the optical assembly may further include a light baffle mounted to the PCB around the image sensor, wherein the image sensor may be fixedly soldered to the PCB beneath the light baffle, and the lens chassis may be fixedly adhered to the PCB around the light baffle. 
     In one or more variations of the current embodiment, an end of the light baffle opposite the image sensor may seal against an end the lens sub-assembly. 
     In one or more variations of the current embodiment, the image sensor may include an interface to communicate images to a controller. The controller may be fixedly soldered to the PCB, and may be configured to decode indicia captured in the images and convey decoded indicia payloads to a host system. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the accompanying figures, like reference numerals refer to identical or functionally similar elements throughout the separate views, together with the detailed description below, are incorporated in and form part of the specification, and serve to further illustrate examples of concepts that include the claimed invention, and explain various principles and advantages of those examples. 
         FIG. 1  is a side cross sectional view of an example optical assembly, in accordance with this disclosure. 
         FIG. 2  is an exploded perspective view of the optical assembly of  FIG. 1 . 
         FIG. 3  is a flowchart representative of example methods, hardware logic and/or machine-readable instructions for assembling an optical assembly, such as the example optical assembly of  FIGS. 1 and 2 . 
         FIGS. 4A, 4B and 4C  are exploded perspective views demonstrating an example assembling of the optical assembly of  FIGS. 1 and 2 , in accordance with the example flowchart of  FIG. 3 . 
         FIG. 5  is a block diagram of an example logic circuit for controlling the assembly of optical assemblies, in accordance with this disclosure. 
     
    
    
     Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and may not have necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of examples of the invention. 
     The assembly and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the examples of the invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein. Skilled artisans will readily recognize from the following discussion that alternate examples of the assemblies and methods illustrated herein may be employed without departing from the principles set forth herein. 
     DETAILED DESCRIPTION 
     Reference will now be made in detail to non-limiting examples, some of which are illustrated in the accompanying drawings. 
     A side cross sectional view of an example optical assembly  100 , in accordance with this disclosure, is shown in  FIG. 1 .  FIG. 2  is an exploded view of the optical assembly  100  of  FIG. 1 . The optical assembly  100  may be used to implement, for example, a camera for capturing images for any number of systems and devices including, but not limited to, machine vision systems, barcode readers, direct part marking (DPM) readers, etc. 
     To capture images, the optical assembly  100  includes an example image sensor  105  and an example lens assembly  110 . The image sensor  105  is configured to receive an image of a target object in a field of view (FOV) of the optical assembly  100  via the lens assembly  110 , and to generate an electrical signal (i.e., an image frame) representative of the image of an environment appearing within a field of view, which may include a target. In the illustrated example of  FIG. 1 , the image sensor  105  is fixedly, mechanically and/or electrically soldered to a printed circuit board (PCB)  115 . The PCB  115  is configured to, among other things, control the image sensor  105  to capture image frames. The PCB  115  may include additional components such as a controller (e.g., one or more generic or specialized processors such as microprocessors, digital signal processors (DSPs), customized processors, field programmable gate arrays (FPGAs), etc.) to control when to activate the image sensor  105  to capture image frames, decode indicia and/or markings captured in images formed at the image sensor  105 , convey decoded indicia payloads to a host system, etc. Additionally, the PCB  115  may include one or more tangible, non-transitory storage memories and/or storage devices for storing the image frame, computer readable instructions for controlling the image sensor  105  and/or, more generally, operations of the PCB  115  or a device that includes the PCB  115 , etc. The PCB  115  may further include a communications module, input/output devices and/or ports for communicating with external systems, devices and networks. In some examples, fixedly coupled, affixed, etc. refers to two components being physically coupled and ready for their intended end use, and not intended for decoupling. 
     In embodiments, the optical assembly  100  may be included in a device (not shown in the illustration for clarity) implemented in housing, such as a machine vision device, barcode reader, etc. that includes additional elements, or may be adapted to be inserted into a docking station with additional elements such as an AC power source to provide power for the device, or another computational device, external network, or communications module for communicating between the device and external devices and systems. The device may further include an onboard power supply such as a battery configured to supply power to the PCB  115 . Additionally, the device may include a memory and a controller that controls operation of the device. In embodiments, the device may include a trigger (not shown in the illustration) that is used to activate the optical assembly  100  to capture an image. The device may include any number of additional components such as a barcode decoder to decode indicia in captured images, decoding systems, processors, and/or circuitry coupled to the PCB  115 , and/or any other circuitry and circuit boards to assist in operation of the device. 
     The image sensor  105  includes a plurality of photosensitive elements forming a substantially flat surface  120 . The image sensor  105  has a defined central imaging axis  125  that is normal to the substantially flat surface  120  formed by the photosensitive elements. 
     The lens assembly  110  may include any number and/or type(s) of optical elements for imaging target objects onto the surface  120  of the image sensor  105 . In embodiments, the lens assembly  110  includes one or more lenses (e.g., aspheric lenses, glass lenses, variable focus lenses, etc.) one of which is designated at reference numeral  130 , filters (e.g., spatial filters, optical filters, apertures, bandpass filters, highpass filters, lowpass filters, notch filters, chromatic filters, neutral density filters, etc.), focus motors, or another component, lens and/or optical element. In embodiments, the lens assembly  110  may be configured to correct or mitigate chromatic dispersion, optical field curvature, coma, chromatic aberrations and/or other optical field distortions. In embodiments, the lens assembly  110  is configured to allow for an image of a target object to be formed as intended on the surface  120  of the image sensor  105 . 
     To capture images of a target object as intended, the image sensor  105  and the lens assembly  110  need to be optically aligned and subsequently held in optical alignment. For example, a defined central imaging axis  135  of the lens assembly  110  and the imaging axis  125  of the image sensor  105  need to be aligned (e.g., be collinear, parallel, etc.). To hold the lens assembly  110  in alignment with the image sensor  105 , the example optical assembly  100  of  FIG. 1  includes an example lens chassis  140  and an example light transmissive lens assembly holder  145 . As shown, the lens chassis  140  encircles the image sensor  105  and is fixedly, mechanically coupled to the PCB  115  with, for example, screws, rivets, solder, adhesive, etc. such that, once assembled, the lens chassis  140  cannot move relative to the image sensor  105 . Thus, the lens chassis  140  provides a solid base relative to the image sensor  105  to which the lens assembly  110  can be held in a fixed optical alignment with the image sensor  105 . 
     The lens assembly holder  145  is configured to fixedly receive the lens assembly  110  to form a lens sub-assembly  150 . Once the lens sub-assembly  150  is formed, the lens assembly  110  cannot move relative to the lens assembly holder  145 . For example, the lens assembly  110  may be press fit with an applied force into the lens assembly holder  145 . Additionally and/or alternatively, the lens assembly  110  may be secured in the lens assembly holder  145  using, for example, adhesive and/or mechanical fastener(s). Additionally and/or alternatively, the lens assembly  110  may be threadably inserted into the lens assembly holder  145 . The lens assembly holder  145  is formed of a light transmissive material, that is, a material (e.g., clear plastic) through which light can pass substantially unimpeded. 
     In the illustrated example, the lens assembly holder  145  or, more generally, the lens sub-assembly  150  is fixedly affixed to the lens chassis  140  with a bead of light-curable adhesive  155 . Once the bead of adhesive  155  is cured, the lens sub-assembly  150  is fixedly affixed to the lens chassis  140  and, thus, the lens assembly  110  becomes held in a fixed optical alignment with the image sensor  105 . 
     During manufacture, before the bead of adhesive  155  is cured, the position of the lens sub-assembly  150  can be adjusted relative to the lens chassis  140  to align the lens assembly  110  with the image sensor  105  using, for example, an active alignment process. Using any number and/or type(s) of algorithm(s), method(s), process(es), etc., active alignment dynamically adjusts the position of the lens sub-assembly  150  relative to the lens chassis  140  based on actual image frames being captured by the image sensor  105 . Images are captured by the image sensor  105  and analyzed while the position of the lens sub-assembly  150  is dynamically adjusted relative to the image sensor  105  (e.g., in five or six degrees of freedom) until captured image frames reflect that the lens assembly  110  is optically aligned with the image sensor  105 , e.g., images that are in focus and properly centered. During active alignment, the lens sub-assembly  150  is held and moved by an active alignment test fixture that includes, for example, a high precision hexapod. 
     Once optical alignment of the lens assembly  110  and image sensor  105  is achieved, the active alignment test fixture holds the lens sub-assembly  150  steady while light (e.g., UV light) is shined on the optical assembly  100  to substantially cure the bead of light-curable adhesive  155 . Because the lens assembly holder  145  is formed of a light transmissive material, the light can pass through the lens assembly holder  145  and substantially cure the bead of light-curable adhesive  155 . For example, the bead of adhesive  155  can be cured solely with light, without any heat being applied, to any desired, designed, intended, etc. extent. For example, fully cured, durably cured, cured to an extent that the holding power of the bead of adhesive  155  satisfies an intended final holding power, cured to an extent that additional curing is not required to ensure the long term mechanical and optical stability of the optical assembly  100 , cured to an extent that the optical assembly  100  can be considered finally assembled, cured to an extent that the optical assembly  100  is durable for its intended use, etc. Once, the bead of adhesive  155  is substantially cured, the lens sub-assembly  150  is fixedly mounted to the lens chassis  140 , the active alignment test fixture can release the lens assembly holder  145 , and the lens assembly  110  will remain durably or fixedly aligned with the image sensor  105 . 
     Because the example lens assembly holder  145  is formed of a light transmissive material, extraneous light may reach the image sensor  105  via the lens assembly holder  145  at an end  160  of the lens assembly  110  and/or via a path  180  between the lens assembly holder  145  and the lens chassis  140 . Thus, in disclosed examples, a light baffle  165  made of an opaque material having a first end  170  and a second end  175  may be used to help prevent extraneous light from reaching the image sensor  105  via the lens assembly holder  145  and/or the path  180 . In some examples, the first end  170  extends to and seals against and around the perimeter of the end  160  of the lens assembly  110 . Alternatively, as shown in  FIG. 1 , the first end  170  need only far enough to form a torturous path for light that enters via the lens assembly holder  145  and/or the path  180 . Most light that enters via the lens assembly holder  145  and/or the path  180  will do so at an angle that causes the light to bounce between the lens assembly holder  145  and the lens chassis  140 , and then enter the cavity formed by the lens chassis  140  at an angle that results in the light falling incident upon and, thus being blocked by, the light baffle  165 . The second opposite end  175  of the light baffle  165  is mounted to (e.g., adhered to) and seals against the PCB  115  around the image sensor  105 . In some examples, the light baffle  165  is formed of a rubber or other flexible material. The light baffle  165  may additionally prevent dust from collecting on the image sensor  105 . 
     As shown in  FIG. 2 , the lens chassis  140  may have two openings to support two side-by-side optical assemblies for, for instance, three-dimensional (3D) vision for a machine vision system. 
     A flowchart  300  representative of example processes, methods, software, computer- or machine-readable instructions, etc. for controlling an assembly line and/or manufacturing equipment (e.g., assembly line  510  of  FIG. 5 ) to assemble an optical assembly, such as the example optical assembly  100  of  FIGS. 1 and 2 , is shown in  FIG. 3 .  FIGS. 4A, 4B and 4C  are exploded perspective views demonstrating an example assembling of an optical assembly in accordance with the example flowchart  300  of  FIG. 3 . The processes, methods, software and instructions may be an executable program or portion of an executable program for execution by one or more processors, such as the processor  502  of  FIG. 5 . The program may be embodied in software or instructions stored on a non-transitory computer- or machine-readable storage medium such as a compact disc (CD), a hard drive, a digital versatile disk (DVD), a Blu-ray disk, a cache, a flash memory, a read-only memory (ROM), a random access memory (RAM), or any other storage device or storage disk associated with the processor  502  in which information is stored for any duration (e.g., for extended time periods, permanently, for brief instances, for temporarily buffering, and/or for caching of the information). Further, although the example program is described with reference to the flowchart illustrated in  FIG. 3 , many other methods of assembling the example optical assembly  100  of  FIGS. 1 and 2  may alternatively be used. For example, the order of execution of the blocks may be changed, and/or some of the blocks described may be changed, eliminated, or combined. Additionally, or alternatively, any or all of the blocks may be implemented by one or more hardware circuits (e.g., discrete and/or integrated analog and/or digital circuitry, an application specific integrated circuit (ASIC), a programmable logic device (PLD), an FPGA, a field programmable logic device (FPLD), a logic circuit, etc.) structured to perform the corresponding operation without executing software or instructions. 
     The example flowchart  300  of  FIG. 3  begins with a PCB  405  (e.g., the PCB  115 ) having an image sensor  410  (e.g., the image sensor  105 ) soldered thereon, a light baffle  415  (e.g., the light baffle  165 ), a lens chassis  420  (e.g., the lens chassis  140 ), a lens assembly  425  (e.g., the lens assembly  110 ) and a lens assembly holder  430  (e.g., the lens assembly holder  145 ) as shown in  FIG. 4A . The light baffle  415  is placed inside the lens chassis  420  (block  305 ) and the lens chassis  420  with the light baffle  415  inside is mounted to the PCB  405  around the image sensor  410  (block  310 ), as shown in  FIG. 4B . The lens assembly  425  is fit into the lens assembly holder  430  to form a lens sub-assembly  435  (block  315 ), as also shown in  FIG. 4B . 
     The PCB  405  with the mounted lens chassis  420  and the lens sub-assembly  435  are placed in an active alignment fixture (block  320 ) (e.g., active alignment fixture  512  of  FIG. 5 ). Light-curable adhesive is dispensed on the lens chassis  420  (block  325 ) and the active alignment fixture optically aligns the lens sub-assembly  435  with the image sensor  410  based on image frames captured by the image sensor  410  (block  330 ). After optical alignment (block  330 ), one or more light sources (e.g., a light source  514  of  FIGS. 1 and 5 ) is activated to shine light  190  (e.g., UV light) on the lens sub-assembly  435  to substantially cure the light-curable adhesive (block  335 ). The light  190  emitted by the light source may pass through the lens assembly holder  430  (e.g., the lens assembly holder  145 ) and/or the gap  180  on to the light-curable adhesive (e.g., the adhesive  155 ). Once the adhesive is substantially cured by the light  190  (block  335 ), as shown in  FIG. 4C , the PCB  405  with the fixedly mounted lens sub-assembly  435  can be removed from the fixture (block  340 ), and assembly of a device including the optical assembly of  FIG. 4C  can continue. 
       FIG. 5  is a block diagram representative of a logic circuit in the form of an example processing platform  500  that may be used to carry out the example flowchart  300  of  FIG. 3  to assemble an optical assembly, in accordance with this disclosure. The processing platform  500  is capable of executing instructions to, for example, implement operations of the example methods described herein. Other example logic circuits capable of, for example, implementing operations of the example methods described herein include FPGAs and ASICs. 
     The example processing platform  500  of  FIG. 5  includes a processor  502  such as, for example, one or more microprocessors, controllers, and/or any suitable type of processor. The example processing platform  500  of  FIG. 5  includes any number or types of non-transitory memory  504  (e.g., volatile memory, non-volatile memory, etc.) and/or storage devices accessible by the processor  502  (e.g., via a memory controller) in which information may be stored for any duration (e.g., permanently, for an extended time period, for a brief instance, for temporarily buffering, for caching of the information, etc.). The example processor  502  interacts with the memory  504  to obtain, for example, computer- or machine-readable instructions stored in the memory  504  corresponding to, for example, the operations disclosed herein. Additionally or alternatively, computer- or machine-readable instructions corresponding to the example operations described herein may be stored on one or more removable media (e.g., an optical storage drive, a CD, a DVD, a removable flash memory, etc.) that may be coupled to the processing platform  500  to provide access to the computer- or machine-readable instructions stored thereon. 
     The example processing platform  500  of  FIG. 5  also includes a network interface  506  to enable communication with other machines via, for example, one or more networks. The example network interface  506  includes any suitable type of communication interface(s) (e.g., wired and/or wireless interfaces) configured to operate in accordance with any suitable protocol(s) like, for example, a TCP/IP interface, a Wi-Fi™ transceiver (according to the IEEE 802.11 family of standards), an Ethernet transceiver, a cellular network radio, a satellite network radio, or any other suitable communication protocols or standards. 
     The example processing platform  500  of  FIG. 5  also includes input/output (I/O) interfaces, circuits, components  508  to enable control of, for example, equipment of the assembly line  510 , the active alignment fixture  512 , the light source  514 , etc. Additionally and/or alternatively, they may be controlled via the network interface  506 . The I/O interfaces, circuits, components  508  may, additionally and/or alternatively, enable the processor  502  to communicate with peripheral I/O devices. Example I/O interfaces, circuits, components  508  include the display  126 , the trigger button  124 , a universal serial bus (USB) interface, a Bluetooth® interface, an NFC interface, the RFID radio  128 , an RFID antenna, a barcode reader, an accelerometer, a global positioning system (GPS) receiver, an imaging assembly, and/or an infrared transceiver. The peripheral I/O devices may be any desired type of I/O device such as a keyboard, a navigation device (e.g., a mouse, a trackball, a capacitive touch pad, a joystick, etc.), a speaker, a microphone, a printer, a button, etc. 
     The above description refers to a block diagram of the accompanying drawings. Alternative implementations of the example represented by the block diagram includes one or more additional or alternative elements, processes and/or devices. Additionally or alternatively, one or more of the example blocks of the diagram may be combined, divided, re-arranged or omitted. Components represented by the blocks of the diagram are implemented by hardware, software, firmware, and/or any combination of hardware, software and/or firmware. In some examples, at least one of the components represented by the blocks is implemented by a logic circuit. As used herein, the term “logic circuit” is expressly defined as a physical device including at least one hardware component configured (e.g., via operation in accordance with a predetermined configuration and/or via execution of stored computer- or machine-readable instructions) to control one or more machines and/or perform operations of one or more machines. Examples of a logic circuit include one or more processors, one or more coprocessors, one or more microprocessors, one or more controllers, one or more DSPs, one or more ASICs, one or more FPGAs, one or more microcontroller units (MCUs), one or more hardware accelerators, one or more special-purpose computer chips, and one or more system-on-a-chip (SoC) devices. Some example logic circuits, such as ASICs or FPGAs, are specifically configured hardware for performing operations (e.g., one or more of the operations described herein and represented by the flowcharts of this disclosure, if such are present). Some example logic circuits are hardware that executes computer- or machine-readable instructions to perform operations (e.g., one or more of the operations described herein and/or represented by the flowcharts of this disclosure, if such are present). Some example logic circuits include a combination of specifically configured hardware and hardware that executes computer- or machine-readable instructions. The above description refers to various operations described herein and/or flowcharts that may be appended hereto to illustrate the flow of those operations. Any such descriptions and/or flowcharts are representative of example methods disclosed herein. In some examples, the methods represented by the flowcharts implement the apparatus represented by the block diagrams. Alternative implementations of example methods disclosed herein may include additional or alternative operations. Further, operations of alternative implementations of the methods disclosed herein may combined, divided, re-arranged or omitted. In some examples, the operations described herein are implemented by computer- or machine-readable instructions (e.g., software and/or firmware) stored on a medium (e.g., a tangible computer- or machine-readable medium) for execution by one or more logic circuits (e.g., processor(s)). In some examples, the operations described herein are implemented by one or more configurations of one or more specifically designed logic circuits (e.g., ASIC(s)). In some examples the operations described herein are implemented by a combination of specifically designed logic circuit(s) and computer- or machine-readable instructions stored on a medium (e.g., a tangible computer- or machine-readable medium) for execution by logic circuit(s). 
     It will be appreciated that some embodiments may be comprised of one or more generic or specialized processors (or “processing devices”) such as microprocessors, digital signal processors, customized processors, FPGAs and unique stored program instructions (including both software and firmware) that control the one or more processors to implement, in conjunction with certain non-processor circuits, some, most, or all of the functions of the method and/or apparatus described herein. Alternatively, some or all functions could be implemented by a state machine that has no stored program instructions, or in one or more ASICs, in which each function or some combinations of certain of the functions are implemented as custom logic. Of course, a combination of the two approaches could be used. 
     Moreover, an embodiment can be implemented as a computer-readable storage medium having computer readable code stored thereon for programming a computer (e.g., comprising a processor) to perform a method as described and claimed herein. Examples of such computer-readable storage mediums include, but are not limited to, a hard disk drive (HDD), a compact disc read only memory (CD-ROM), an optical storage device, a magnetic storage device, a ROM, a PROM (Programmable Read Only Memory), an EPROM (Erasable Programmable Read Only Memory), an EEPROM (Electrically Erasable Programmable Read Only Memory) and a Flash memory. Further, it is expected that one of ordinary skill, notwithstanding possibly significant effort and many design choices motivated by, for example, available time, current technology, and economic considerations, when guided by the concepts and principles disclosed herein will be readily capable of generating such software instructions and programs and ICs with minimal experimentation. 
     In the foregoing specification, specific embodiments have been described. However, one of ordinary skill in the art appreciates that various modifications and changes can be made without departing from the scope of the invention as set forth in the claims below. Accordingly, the specification and figures are to be regarded in an illustrative rather than a restrictive sense, and all such modifications are intended to be included within the scope of present teachings. Additionally, the described embodiments/examples/implementations should not be interpreted as mutually exclusive, and should instead be understood as potentially combinable if such combinations are permissive in any way. In other words, any feature disclosed in any of the aforementioned embodiments/examples/implementations may be included in any of the other aforementioned embodiments/examples/implementations. 
     The benefits, advantages, solutions to problems, and any element(s) that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as a critical, required, or essential features or elements of any or all the claims. The invention is defined solely by the appended claims including any amendments made during the pendency of this application and all equivalents of those claims as issued. 
     Moreover in this document, relational terms such as first and second, top and bottom, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. The terms “comprises,” “comprising,” “has”, “having,” “includes”, “including,” “contains”, “containing” or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises, has, includes, contains a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by “comprises . . . a”, “has . . . a”, “includes . . . a”, “contains . . . a” does not, without more constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that comprises, has, includes, contains the element. The terms “a” and “an” are defined as one or more unless explicitly stated otherwise herein. The terms “substantially”, “essentially”, “approximately”, “about” or any other version thereof, are defined as being close to as understood by one of ordinary skill in the art, and in one non-limiting embodiment the term is defined to be within 10%, in another embodiment within 5%, in another embodiment within 1% and in another embodiment within 0.5%. The term “coupled” as used herein is defined as connected, although not necessarily directly and not necessarily mechanically. A device or structure that is “configured” in a certain way is configured in at least that way, but may also be configured in ways that are not listed. 
     Further, unless expressly stated to the contrary, “or” refers to an inclusive or and not to an exclusive or. For example, A, B or C refers to any combination or subset of A, B, C such as (1) A alone, (2) B alone, (3) C alone, (4) A with B, (5) A with C, (6) B with C, and (7) A with B and with C. As used herein, the phrase “at least one of A or B” is intended to refer to implementations including any of (1) at least one A, (2) at least one B, and (3) at least one A and at least one B. Similarly, the phrase “at least one of A and B” is intended to refer to implementations including any of (1) at least one A, (2) at least one B, and (3) at least one A and at least one B. The term “and/or” when used, for example, in a form such as A, B, and/or C refers to any combination or subset of A, B, C such as (1) A alone, (2) B alone, (3) C alone, (4) A with B, (5) A with C, (6) B with C, and (7) A with B and with C. 
     As used herein, the expressions “in communication,” “coupled” and “connected,” including variations thereof, encompasses direct communication and/or indirect communication through one or more intermediary components, and does not require direct physical (e.g., wired) communication and/or constant communication, but rather additionally includes selective communication at periodic intervals, scheduled intervals, aperiodic intervals, and/or one-time events. 
     The Abstract of the Disclosure is provided to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing Detailed Description, it can be seen that various features are grouped together in various embodiments for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed embodiment. Thus the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separately claimed subject matter.