Abstract:
An optical system comprising a non-specular ceramic reflector surrounding one or more electrode-less bulbs containing a fill that forms a light-emitting plasma when excited with radio frequency, to be used in a fixture for illuminating subjects, for the purpose of high output lighting, such as lighting for image capture, horticulture, stadium, port, roadway, construction and area lighting. This ceramic reflector generates a uniform lambertian reflection specifically evening out the light emission from the electrode-less bulb producing a uniform beam of light with a spread between about 1 to about 300 degrees. This ceramic reflector greatly increases the amount of light falling on a given subject in comparison to the fixture without said reflector system. The beam of light created by this optical system may then be altered by the fixture by using a combination of further optical elements including but not limited to one or more lenses, one or more additional reflectors, one or more mirrors and one or more filter materials, which may be mounted inside our outside of the light fixture. The lenses and/or filters can be adjusted in distance from the light elements, for example by moving the lenses/filters into different positions on the fixture, to alter characteristics of the emitted light. Focal lenses, diffusion lenses, reflectors and color filters may be used individually or in combination.

Description:
INCORPORATION BY REFERENCE TO ANY PRIORITY APPLICATIONS 
       [0001]    Any and all applications for which a foreign or domestic priority claim is identified in the Application Data Sheet as filed with the present application are hereby incorporated by reference under 37 CFR 1.57. 
         [0002]    The present application claims priority under 35 U.S.C. 119(e) to U.S. Provisional Patent Application No. 61/886001 filed Oct. 2, 2013, the entire contents of which are hereby incorporated by reference and should be considered a part of this specification 
     
    
     BACKGROUND 
       [0003]    1. Field 
         [0004]    The present invention is directed to an optical system as it relates to a lighting fixture, and more particularly to an optical system that can be used in a lighting fixture for high output lighting, specifically but not limited to use in image capture, horticulture, stadium, port, roadway, construction and area lighting. 
         [0005]    2. Description of the Related Art 
         [0006]    Lighting systems are an integral part of multiple industries; specifically high output lighting is required for specific industries such as image capture, horticulture, stadium, port, roadway, construction and area lighting. High output lighting can be understood as lighting fixtures that provide acceptable levels of illumination for a variety of activities from a distance of about 25 ft or greater, or high levels of illumination from distances under about 25 ft. This can be understood to be separate and distinct from common low output lighting fixtures designed for domestic and office use internal to structures with average ceiling heights of 8-15 ft. 
         [0007]    Proper illumination from a distance is necessary for a variety of industries. In image capture when filming movies, television shows, or commercials, when shooting video clips, or when taking still photographs, whether such activities are carried out indoors or outdoors and proper exposure requires a variety of light levels to be achieved from a variety of distances between a lighting fixture and the subject. A specific illumination effect might also be desired for live performances on stage or in any other type of setting where bringing the fixture closer to the subject is impossible. Proper illumination from a distance is also necessary for stadium lighting, area, and roadway lighting where light fixtures cannot impede the view of participants, attendees and drivers, respectively. For port and construction lighting, fixtures must rise above the heights of large equipment, while effectively directing light to surfaces at which technicians are working, and beyond. 
         [0008]    Proper illumination from high output fixtures used from distances less than 25 ft to create illumination levels higher than average domestic levels of illumination are also necessary for a variety of industries. In the image capture industries when filming movies, television shows, or commercials, when shooting video clips, or when taking still photograph to create acceptable illumination levels, high output lighting may be used to rival or balance daylight from the sun, or provide light levels needed for certain technical requirements like low sensitivity capture equipment, high shutter speeds or high frame rates. In other technical industries, high illumination levels may be need to create daylight like scenarios in indoor or controlled settings, for testing durability and light sensitivity of equipment. In horticultural applications, growing plant life in artificial settings requires the use of light sources to create the needed conditions for photosynthesis, where higher light levels may result in a more successful growth cycles and yields. 
         [0009]    A primary purpose of such a lighting fixture is to illuminate a subject to allow proper image capture or achieve a desired effect. Often it is desirable to obtain even lighting that minimizes shadows on or across the subject. It may be necessary or desirable to obtain lighting that has a certain shape, tone, color, or intensity. It may also be necessary or desirable to have certain lighting effects, such as colorized lighting, strobed lighting, gradually brightening or dimming illumination, or different intensity illumination in different fields of view. 
         [0010]    Because of the varied settings in which lighting fixtures for high output lighting are used, the conventional practice in the related industries are for a lighting system, when needed, to be custom designed for high output lighting. A lighting apparatus specially adapted for general illumination and low output lighting is generally not suitable for the special needs of high output lighting in industries such as image capture, horticulture, stadium, port, roadway, construction and area lighting, because the lighting needs in these fields differs substantially from what is offered by a general or low output lighting apparatus. Indeed, general or low output lighting apparatuses are generally designed for levels of illumination, at a distance, which are too minimal for the industries requiring high output lighting fixtures. 
         [0011]    Electrode-less bulbs containing a fill that forms light-emitting plasma are a known light source and can be used as a light source in a variety of fixtures. An integral part of any fixture designed for high output lighting is its optical reflector system. This reflector system is designed to create even lighting with unique properties, such as greater output and or the ability create specific shapes and lighting effects. Since electrode-less bulbs have unique properties they need unique reflector systems to make them applicable for high output lighting. 
         [0012]    Current reflectors for low output lighting do not produce a significant increase in the output compared to reflectors used for high output lighting. Also current reflectors when not designed for high output lighting may produce light where the quality of the light emitted from the fixture is negatively affected, such as changing the color and/or evenness of the projected beam light and/or creating multiple shadows, or inferior reflectivity, as well as other undesired effects. There are current optical reflector systems designed for high output lighting for previously existing bulbs such as incandescent and metal halide bulbs, but because of the unique properties of an electrode-less bulb and light emitting plasma, resulting from such elements as the specific arc size of an electrode-less bulb, the physical size as well as the uneven emission of the light from many plasma sources, their optical design is incompatible. 
         [0013]    Reflector materials commonly in use in high output lighting are aluminum and dichroic glass. These materials may be formed, treated and given a variety of coatings to create the desired attributes such as color, output, and angle in the beam of light formed. However these existing reflectors and materials were not designed with the properties of light-emitting plasma in mind. The smaller size of the electrode-less bulb and the arc in comparison to the great deal of lumens emitted results in a greater propensity for spectral highlights making many aluminum reflectors unable to function as efficiently and to create an even light distribution. Also the small size of the bulb, the high temperatures required for the bulb&#39;s operation to maintain the formation of a plasma, and its small arc requires reflectors to be much smaller and closer to point source origin, making it impossible for many of the coatings common amongst existing reflectors in use as such coatings would degrade at the operating temperatures associated with electrode-less bulb operation. 
       SUMMARY 
       [0014]    The invention is generally directed in one aspect to a novel and unique reflector system for an electrode-less bulb. This reflector system being comprised of a high efficiency diffuse ceramic material is then paired with one or more electrode-less bulbs containing a fill that forms a light-emitting plasma when excited with radio frequency, to be used in a fixture for illuminating subjects, for the purpose of high output lighting, such as lighting for image capture, stadium, port, roadway, construction and area lighting. 
         [0015]    It would be advantageous to provide a lighting fixture using an electrode-less bulb that has an optical system, particularly in the form of a reflector that is designed for use in high output lighting that will maximize the benefits of light-emitting plasma and produce large amounts of continuous, flicker free light using less power, and generating less heat that may find use in a variety of applications. It would further be advantageous to provide a lighting fixture using an electrode-less bulb with a specific optical system, with a reflector made from a new material, specifically a ceramic, which allows the fixture to produce large amounts of continuous, flicker free light using less power, and generating less heat that is well suited for use in high output lighting for image capture, horticulture, stadium, port, roadway, construction and area lighting, that overcomes one or more of the foregoing disadvantages, drawbacks, or limitations as described in the background. It would further be advantageous if that ceramic reflector projected light with an even lambertian field, a singular shadow, and all, substantially all or the vast majority of all the lumens produced by the bulb in the desired direction. 
         [0016]    This ceramic reflector will create a non-specular, lambertian beam of light, which can then be paired with a series of optical systems, such as lenses, additional reflectors, mirrors and filters, both inside and outside a lighting fixture. The resulting luminaire will produce a more even and controllable beam of light as well as more efficiently direct lumens onto the intended subject for illumination. 
         [0017]    In accordance with one aspect of the invention, an optical system is provided. The optical system comprises reflector made of a non-specular, highly reflective ceramic material. The optical system also comprises an electrode-less bulb coupleable with the reflector to produce a homogenous and lambertian beam of light, the electrode-less bulb filled with a gas that forms a light-emitting plasma when excited. 
         [0018]    Optionally, one or more lenses are operatively coupleable with one or both of the reflector and electrode-less bulb to alter the characteristics of beam of light produced by said optical system. The one or more lenses can be selected from the group consisting of a Fresnel lens, a lenticular lens, a convex lens, a bi-convex lens and a plano-convex lens. Optionally, a highly reflective mirrored surface can be operatively coupled to one or both of the reflector and electrode-less bulb, the mirrored surface configured to redirect the beam of light. 
         [0019]    Optionally, one or more colored filters or dimmers, or diffusion are operatively coupled to one or both of the reflector and the electrode-less bulb to alter one or both of the characteristics and output of the beam of light produced by said optical system. Optionally, a highly reflective mirrored surface can be operatively coupled to one or both of the reflector and electrode-less bulb, the mirrored surface configured to redirect the beam of light. 
         [0020]    In accordance with another aspect of the invention, an optical system is provided. The optical system comprises at least one reflector body having a proximal opening and a distal opening and an inner circumferential wall between the proximal and distal openings that defines a space within the body. The distal opening is larger than the proximal opening and the proximal opening is defined at least in part by a lip that extends inward from the inner circumferential wall and has a chamfered edge. The inner circumferential wall is made of a non-specular highly reflective ceramic material. The optical system further comprises an electrode-less bulb coupleable with the at least one reflector body to produce a homogenous and lambertian beam of light. The electrode-less bulb is configured to extend at least partially through the proximal opening and into the space defined by the inner circumferential wall. The electrode-less bulb is filled with a gas that forms a light-emitting plasma when excited. 
         [0021]    In accordance with another aspect of the invention, a method of making a high-output optical system is provided. The method comprises selecting one of a plurality of interchangeable reflector bodies, each reflector body having a proximal opening and a distal opening and an inner circumferential wall between the proximal and distal openings that defines a space within the body, wherein the distal opening is larger than the proximal opening and the proximal opening is defined at least in part by a lip that extends inward from the inner circumferential wall and has a chamfered edge, the inner circumferential wall made of a non-specular highly reflective ceramic material. The method also comprises inserting an electrode-less bulb at least partially through the proximal opening so that the electrode-less bulb extends into the space defined by the inner circumferential wall, the electrode-less bulb filled with a gas that forms a light-emitting plasma when excited. The method also comprises operating the electrode-less bulb, once coupled to said selected reflector body to produce a homogenous and lambertian beam of light, wherein a distance from the electrode-less bulb to the chamfered edge of the proximal opening is substantially the same for the plurality of interchangeable reflector bodies. 
         [0022]    These and other objects, features and advantages of the present invention will become more apparent from the detailed description of the preferred embodiment when read in conjunction with the drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0023]      FIGS. 1A and 1B  show a schematic front end view and a schematic cross-sectional side view, respectively, of one embodiment of a non-specular, high efficiency diffuse ceramic reflector with a beam angle of 50 degrees for use in an optical system. 
           [0024]      FIGS. 2A and 2B  show a schematic front end view and a schematic cross-sectional side view, respectively, of another embodiment of a non-specular, highly efficiency diffuse, ceramic reflector, with a beam angle of 110 degrees for use in an optical system. 
           [0025]      FIG. 3  is a schematic view of one embodiment of an optical system having one possible non-specular, high efficiency diffuse ceramic reflector in combination with one possible electrode-less bulb containing a fill that when excited forms a light emitting plasma. 
           [0026]      FIG. 4  is a schematic view of the optical system of  FIG. 3  in combination with a flat borosilicate glass lens for the purpose of trapping both ultra-violet and infrared radiation while allowing all or most of the emission from the light emitting plasma in the visible electromagnetic spectrum to pass through the flat borosilicate glass lens. 
           [0027]      FIG. 5  is a schematic view of one embodiment of an optical system combining one embodiment of a ceramic reflector with an electrode-less bulb and a Fresnel lens. The Fresnel lens&#39; distance from the reflector and bulb can be adjustable allowing the beam of light to change, effectively spotting and flooding the light coming from the luminaire in which the optical system was integrated. 
           [0028]      FIG. 6  is a schematic view of one embodiment of an optical system combining one embodiment of a ceramic reflector with an electrode-less bulb, a bi-convex lens and a lenticular lens to allow both the spread and focus the beam of light further depending on the combination. 
           [0029]      FIG. 7  is a schematic view of one embodiment of an optical system combining one embodiment of a ceramic reflector with an adjustable glass dichroic mirror to redirect the beam of light with virtually no light loss to in a desired direction between 0-90 degrees from the original beam angle of the lamp. 
       
    
    
     DETAILED DESCRIPTION 
       [0030]      FIGS. 1A-1B  illustrate one embodiment of a reflector for an optical system for high output lighting, specifically a reflector  101  made of a non-specular, highly reflective ceramic material. This reflector  101  may be generally cylindrical in shape and would surround an electrode-less bulb, where the bulb would be inserted into the reflector through a proximal circular opening  102 . In the illustrated embodiment, the proximal opening  102  can have a diameter of about 16.2 mm with a 110 degree slope. The light emitted from this electrode-less bulb would exit through a distal circular opening  103  at an opposite end of the reflector  101  from the proximal opening  102 . The distal opening  103  can be larger than the proximal opening  102 . In the illustrated embodiment, the distal opening  103  can have a diameter of about 25 mm. While in the illustrated embodiment the proximal and distal openings  102 ,  103  are circular, and the reflector  101  is cylindrical, multiple geometric shapes such as hexagonal, rectangular and conical reflectors could be used to create different effects and efficiencies in the resulting projected beam of light. In one embodiment, the distance from the electrode-less bulb to the edge of the reflector opening  102  is substantially constant among the different reflectors  101  (e.g., said distance from the electrode-less bulb to the edge of the reflector opening  102  is substantially the same for the 50 degree reflector, the 110 degree reflector, etc.) to allow the resulting lighting assembly to provide a desired tight or focused beam of light. In  FIGS. 1A-1B  the reflector&#39;s  101  internal wall  104  (e.g. internal circumferential wall) can be composed of a 95-99.9% reflective uncoated ceramic surface material composed of high purity metal oxides free of transition metals and their compounds with virtually no specular reflection. One such highly reflective material suitable for this application is the product Accuflect™ produced by the Accuratus company of Phillipsburg, N.J. The proximal opening  102  is defined by a lip  102   a  that extends inwardly from the internal wall  104 . The lip  102   a  can have a chamfered edge  102   b.    
         [0031]    With continued reference to  FIGS. 1A-1B , the reflector  101  can have a height of about 34 mm and would create a beam of light projected from its opening  103  with a beam angle of about 50 degrees when properly mounted to an electrode-less bulb centered  105  within the non-specular, highly reflective ceramic material. Advantageously, this 50-degree beam of light would be homogenous and lambertian in nature and would create a singular shadow. 
         [0032]    In further detail  FIGS. 2A-2B  illustrate another embodiment of a reflector for an optical system for high output lighting, specifically a reflector  201  made of a non-specular, highly reflective ceramic material. This reflector  201  may be cylindrical and would surround an electrode-less bulb, the bulb would be inserted into the reflector through a proximal circular opening  202 , and the light emitted from this electrode-less bulb would exit through a distal circular opening  203  that is larger than the proximal opening  202 . While in the illustrated embodiment the proximal and distal openings  202 ,  203  are circular and the reflector  201  is cylindrical, multiple geometric shapes such as hexagonal, rectangular and conical reflectors could be used to create different effects and efficiencies in the resulting projected beam of light. In  FIGS. 2A-2B , the reflector&#39;s  201  internal walls  204  (e.g., internal circumferential wall) can be made of a 95-99.9% reflective uncoated ceramic surface material composed of high purity metal oxides free of transition metals and their compounds with virtually no specular reflection. The reflector  201 , in the illustration in  FIGS. 2A-2B  would create a beam of light projected from its distal opening  203  with a beam angle of about 110 degrees when properly mounted to an electrode-less bulb centered  205 , within the non-specular, highly reflective ceramic material. Advantageously, this 110-degree beam of light would be homogenous and lambertian in nature. The proximal opening  202  is defined by a lip  202   a  that extends inwardly from the internal wall  204 . The lip  202   a  can have a chamfered edge  202   b.    
         [0033]    In more detail  FIG. 3  is an illustration of one embodiment of an optical system for high output lighting combining a reflector  301  made of a non-specular, highly reflective ceramic material and an electrode-less gas filled bulb  302  containing a fill that forms a light-emitting plasma when excited with radio frequency. The reflector  301  can in one embodiment be similar to the reflector  101 . In another embodiment, the reflector  301  can be similar to the reflector  201 . Combined, the reflector  301  and electrode-less gas filled bulb  302  form a unique optical system for high output illumination. 
         [0034]      FIG. 4  illustrates an embodiment of an optical system combing a reflector  401  made of a non-specular, highly reflective ceramic material. In this preferred embodiment this reflector  401  surrounds an electrode-less bulb  402 , light  404  is emitted from this bulb, and is reflected by the ceramic reflector  401  and projected in a 50-degree lambertian beam towards a flat lens  403 . The reflector  401  can in one embodiment be similar to the reflector  101 . This lens  403  may be made of either glass or plastic, and may be translucent or transparent in nature designed to transmit all or some of the light projected from the reflector  401 . 
         [0035]    In one embodiment as illustrated in  FIG. 4  this lens  403  is made of transparent borosilicate glass of 3 mm thickness or greater, designed to block the transmission of both infrared and ultraviolet radiation while allowing the vast majority of light  404  in the visible spectrum to pass through the lens  403  unaltered. 
         [0036]    In another embodiment, the lens  403  is made of a material such as a dichroic glass or dyed plastic designed to block the transmission of the electrode-less bulb&#39;s  402  spectrum to result in a specific color temperature as measured in degrees Kelvin. Such commonly desired color temperatures as 2900 degrees Kelvin, 3200 degrees Kelvin, 4800 degrees Kelvin, 5600 degrees Kelvin, 6000 degrees Kelvin and 6500 degrees Kelvin could be achieved, though other color temperatures are possible. 
         [0037]    In another embodiment, the lens  403  is made of a dichroic glass or dyed plastic designed to block or limit the transmission of the light  404  emitted from the electrode-less bulb  402  to result in a very limited spectrum, defined by the vast majority of light limited to a specific nanometer in the electromagnetic spectrum. In this embodiment, the lens  402  is made of a material such as dichroic glass or dyed plastic designed to limit the transmission of the optical system to commonly desired nanometers for specific industries, such as 420 nm or 450 nm or 525 nm or 650 nm. 
         [0038]      FIG. 5  illustrates one embodiment of an optical system combining a reflector  501  made of a non-specular, highly reflective ceramic material. In the illustrated embodiment, the reflector  501  surrounds an electrode-less bulb  502  and light  505  emitted from this bulb is reflected by the ceramic reflector  501  and projected in a 50-degree lambertian beam towards a Fresnel lens  503 . While the orientation and distance between bulb  502  and reflector  501  are fixed, the distance between this Fresnel lens  503  and the bulb  502  and reflector  501  can be adjusted  504  to create a spotting at flooding effect from the resulting beam of light collimated and projected from the Fresnel lens  503 . This adjusted distance  504  can be achieved either by moving the Fresnel lens  503  in relationship to the bulb  502  and reflector  501  or by moving the bulb  502  and reflector  501  in relationship to the Fresnel lens  503  or by moving some combination of both. 
         [0039]      FIG. 6  shows an embodiment of an optical system combining a reflector  602  made of a non-specular, highly reflective ceramic material and an electrode-less bulb containing a fill that when excited with radio frequency creates a light-emitting plasma. In this embodiment, this reflector  602  surrounds an electrode-less bulb  601 , light  605  is emitted from this bulb  601 , and is reflected by the ceramic reflector  602  and projected in a 50-degree lambertian beam towards a biconvex lens  603  which collimates the light  606  into a lenticular lens  604 . In the illustrated embodiment, the biconvex lens  603  would focus the 50-degree beam angle created by the reflector  602  to a desired smaller beam angle. In other embodiments, different lenticular lens  604  can be used to spread the collimated light  606  from the biconvex lens  603  into a different desired beam angle. 
         [0040]      FIG. 7  illustrates an embodiment of an optical system combining a reflector  701  made of a non-specular, highly reflective ceramic material with an electrode-less bulb  702  containing a fill that when excited with radio frequency creates a light-emitting plasma. In this preferred embodiment this reflector  701  surrounds an electrode-less bulb  702 , light  704  is emitted from this bulb  702 , and is reflected by the ceramic reflector  701  and projected onto a mirrored surface  703 . In this embodiment the mirrored surface  703  can be made of a material substrate such as glass, metal or plastic with the resulting mirror  703  having virtually no light loss. The mirror  703  is adjustable allowing for redirection of the beam of light with virtually no light loss in a desired direction between 0-90 degrees from the original beam angle of the lamp. 
         [0041]    Various embodiments have been described as having particular utility to high output lighting for various applications in industries such as image capture, horticulture, stadium, port, roadway, construction and area lighting. However, the various embodiments may find utility in other areas as well, such as, for example, automated manufacturing, machine vision, event lighting and the like. 
         [0042]    While certain embodiments of the inventions have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the disclosure. Indeed, the novel methods and systems described herein may be embodied in a variety of other forms. Furthermore, various omissions, substitutions and changes in the systems and methods described herein may be made without departing from the spirit of the disclosure. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the disclosure. Accordingly, the scope of the present inventions is defined only by reference to the appended claims. 
         [0043]    Features, materials, characteristics, or groups described in conjunction with a particular aspect, embodiment, or example are to be understood to be applicable to any other aspect, embodiment or example described in this section or elsewhere in this specification unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. The protection is not restricted to the details of any foregoing embodiments. The protection extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed. 
         [0044]    Furthermore, certain features that are described in this disclosure in the context of separate implementations can also be implemented in combination in a single implementation. Conversely, various features that are described in the context of a single implementation can also be implemented in multiple implementations separately or in any suitable subcombination. Moreover, although features may be described above as acting in certain combinations, one or more features from a claimed combination can, in some cases, be excised from the combination, and the combination may be claimed as a subcombination or variation of a sub combination. 
         [0045]    Moreover, while operations may be depicted in the drawings or described in the specification in a particular order, such operations need not be performed in the particular order shown or in sequential order, or that all operations be performed, to achieve desirable results. Other operations that are not depicted or described can be incorporated in the example methods and processes. For example, one or more additional operations can be performed before, after, simultaneously, or between any of the described operations. Further, the operations may be rearranged or reordered in other implementations. Those skilled in the art will appreciate that in some embodiments, the actual steps taken in the processes illustrated and/or disclosed may differ from those shown in the figures. Depending on the embodiment, certain of the steps described above may be removed, others may be added. Furthermore, the features and attributes of the specific embodiments disclosed above may be combined in different ways to form additional embodiments, all of which fall within the scope of the present disclosure. Also, the separation of various system components in the implementations described above should not be understood as requiring such separation in all implementations, and it should be understood that the described components and systems can generally be integrated together in a single product or packaged into multiple products. 
         [0046]    For purposes of this disclosure, certain aspects, advantages, and novel features are described herein. Not necessarily all such advantages may be achieved in accordance with any particular embodiment. Thus, for example, those skilled in the art will recognize that the disclosure may be embodied or carried out in a manner that achieves one advantage or a group of advantages as taught herein without necessarily achieving other advantages as may be taught or suggested herein. 
         [0047]    Conditional language, such as “can,” “could,” “might,” or “may,” unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements, and/or steps. Thus, such conditional language is not generally intended to imply that features, elements, and/or steps are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without user input or prompting, whether these features, elements, and/or steps are included or are to be performed in any particular embodiment. 
         [0048]    Conjunctive language such as the phrase “at least one of X, Y, and Z,” unless specifically stated otherwise, is otherwise understood with the context as used in general to convey that an item, term, etc. may be either X, Y, or Z. Thus, such conjunctive language is not generally intended to imply that certain embodiments require the presence of at least one of X, at least one of Y, and at least one of Z. 
         [0049]    Language of degree used herein, such as the terms “approximately,” “about,” “generally,” and “substantially” as used herein represent a value, amount, or characteristic close to the stated value, amount, or characteristic that still performs a desired function or achieves a desired result. For example, the terms “approximately”, “about”, “generally,” and “substantially” may refer to an amount that is within less than 10% of, within less than 5% of, within less than 1% of, within less than 0.1% of, and within less than 0.01% of the stated amount. As another example, in certain embodiments, the terms “generally parallel” and “substantially parallel” refer to a value, amount, or characteristic that departs from exactly parallel by less than or equal to 15 degrees, 10 degrees, 5 degrees, 3 degrees, 1 degree, or 0.1 degree. 
         [0050]    The scope of the present disclosure is not intended to be limited by the specific disclosures of preferred embodiments in this section or elsewhere in this specification, and may be defined by claims as presented in this section or elsewhere in this specification or as presented in the future. The language of the claims is to be interpreted broadly based on the language employed in the claims and not limited to the examples described in the present specification or during the prosecution of the application, which examples are to be construed as non-exclusive.