Abstract:
A luminaire with a prismatic optic permits the nearly uniform distribution of light about the luminaire. The prismatic optic permits the use of directional light sources, such as light emitting diodes, while maintaining the uniform light distribution. When light emitting diodes are used, the luminaire further includes a heat sink to maintain a desirable operational temperature without negatively affecting the light distribution properties of the luminaire.

Description:
RELATED APPLICATIONS 
       [0001]    This application is related to and claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application Ser. No. 61/642,205 titled Luminaire with Prismatic Optic filed May 3, 2012, the contents of which are incorporated in their entirety herein. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to systems and methods for generating light, and more particularly, a system for effectively distributing light substantially about a light bulb. 
       BACKGROUND OF THE INVENTION 
       [0003]    Achieving nearly uniform light distribution about a light bulb has long been a goal in the lighting industry. Success in this goal has largely depended upon the method of providing light employed by the bulb. Specifically, different methods of light generation produce light with different distributions, which must be compensated for in the construction of the bulb. 
         [0004]    Most of the earliest light bulbs were incandescent, which generate light by heating a filament wire until it glows. Due to the relatively sparse nature of the supporting structures necessary for the filament, and due to the 360-degree dispersion of light by the filament, achieving nearly uniform distribution about an incandescent light bulb was not difficult to achieve. However, due to inefficiencies in the method of light production employed in incandescent light bulbs, other methods are desirable. 
         [0005]    Fluorescent lamps, specifically compact fluorescent lamps (CFLs), have been steadily replacing incandescent light bulbs in many lighting applications. Similar to incandescent, CFLs produce light in approximately 360 degrees by exciting mercury vapor to cause a gas discharge of light. CFLs are more energy efficient than incandescent light bulbs, but suffer a number of undesirable traits. Many CFLs have poor color temperature, resulting in a less aesthetically pleasing light. Some CFLs have prolonged warm-up times, requiring up to three minutes before maximum light output is achieved. All CFLs contain mercury, a toxic substance that must be handled carefully and disposed of in a particular manner. Furthermore, CFLs suffer from a reduced life span when turned on and off for short period. Therefore, there are a number of disadvantages to using CFLs in a lighting system. 
         [0006]    Light emitting diodes (LEDs) are increasingly being used as the light source in light bulbs. LEDs offer greater efficiencies than CFLs, have an increased life span, and are increasingly being designed to have desirable color temperatures. Moreover, LEDs do not contain mercury or any other toxic substance. However, by the very nature of their design and operation, LEDs have a directional output. Accordingly, the light emitted by an LED may not have the nearly omni-directional and uniform light distribution of incandescents and CFLs. Although multiple LEDs can and frequently are used in a single light bulb, solutions presented so far do not have light distribution properties approximating or equaling the dispersion properties of incandescents or CFLs. Accordingly, there is a long felt need for a light bulb that can utilize LEDs as a light source while maintaining uniform and nearly omni-directional light distribution properties. 
         [0007]    One issue facing the use of LEDs to replace traditional light bulbs is heat. LEDs suffer damage and decreased performance when operating in high-heat environments. Moreover, when operating in a confined environment, the heat generated by the LED and its attending circuitry itself can cause damage to the LED. Heat sinks are well known in the art and have been effectively used to provide cooling capacity, maintaining an LED-based light bulb within a desirable operating temperature. However, heat sinks can sometimes negatively impact the light distribution properties of the light bulb, resulting in non-uniform distribution of light about the bulb. Accordingly, there is a long felt need for an LED-based light bulb capable of providing uniform light distribution that maintains a desirable operating temperature. 
         [0008]    This background information is provided to reveal information believed by the applicant to be of possible relevance to the present invention. No admission is necessarily intended, nor should be construed, that any of the preceding information constitutes prior art against the present invention. 
       SUMMARY OF THE INVENTION 
       [0009]    With the foregoing in mind, embodiments of the present invention are related to a luminaire that utilizes a prismatic optic to distribute light from a light emitting element within the luminaire approximately uniformly about the luminaire. The luminaire, according to embodiments of the present invention, can also advantageously combine this prismatic optic with one or more light emitting diodes (LEDs) as a light source, overcoming previous deficiencies in LED-based luminaire designs. 
         [0010]    These and other objects, features, and advantages according to the presenting invention are provided by a luminaire including a light source and a prismatic optic. The light source may include one or more LEDs that emit light that is incident upon the prismatic optic. The prismatic optic, in turn, may refract the light substantially about the luminaire, resulting in approximately omni-directional and uniform light distribution. The luminaire may further include a base for connection to a light socket and a heat sink for cooling the light source. The base may be attached to the heat sink, which is, in turn, attached to the light source and the prismatic optic. A surface of the heat sink may have reflective properties configured to reflect light generally towards the prismatic optic. The luminaire may further include a circuit board including circuitry configured to power the light source. The circuit board may be positioned so as to be optimally cooled by the heat sink. 
         [0011]    The prismatic optic, according to embodiments of the present invention, may be configured to have specific light refracting properties. Specifically, the prismatic optic may refract light within certain regions with certain uniformities. The light may be refracted within regions of 0 degrees to 135 degrees, 135 degrees to 150 degrees, and 150 degrees to 180 degrees. Furthermore, the light may be of uniform intensity to within a certain percentage of an average intensity, such as within 20%, within 10%, within 5%, or within 1%. 
         [0012]    The light source may include a platform upon which one or more LEDs may be attached. The LEDs may be attached to an upper surface and/or a lower surface of the platform, increasing light distribution. Furthermore, the platform may include a section within which the LEDs may be attached that facilitates electric coupling between the LEDs and the circuit board. 
         [0013]    A method aspect of the present invention is for using the luminaire. The method may include the steps of generating light and refracting light according to a desired light distribution. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]      FIG. 1  is a side view of a luminaire according to an embodiment of the present invention. 
           [0015]      FIG. 2  is a perspective view of a lower structure of the luminaire presented in  FIG. 1 . 
           [0016]      FIG. 3  is a perspective view of a prismatic optic of the luminaire presented in  FIG. 1 . 
           [0017]      FIG. 4   a  is a partial top view of the luminaire presented in  FIG. 1 . 
           [0018]      FIG. 4   b  is a partial bottom view of the luminaire presented in  FIG. 1 . 
           [0019]      FIG. 5  is a partial side sectional view of the prismatic optic of the luminaire presented in  FIG. 1 . 
           [0020]      FIG. 6  is a perspective view of an upper structure of the luminaire presented in  FIG. 1 . 
           [0021]      FIG. 7  is a partial side sectional view of the upper section presented in  FIG. 6 . 
           [0022]      FIG. 8  is a perspective view of a light source used in connection with the luminaire presented in  FIG. 1 . 
           [0023]      FIG. 9   a  is a perspective view of a housing used in connection with the luminaire presented in  FIG. 1   
           [0024]      FIG. 9   b  is a side sectional view of the luminaire presented in  FIG. 1  taken through line  9   b - 9   b.    
           [0025]      FIG. 10  is a perspective view of a cap used in connection with the luminaire presented in  FIG. 1 . 
           [0026]      FIG. 11  is a perspective view of the cross section view of the luminaire as presented in  FIG. 9   b.    
           [0027]      FIG. 12  is a polar graphical illustration representing a light distribution of the luminaire presented in  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0028]    The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Those of ordinary skill in the art realize that the following descriptions of the embodiments of the present invention are illustrative and are not intended to be limiting in any way. Other embodiments of the present invention will readily suggest themselves to such skilled persons having the benefit of this disclosure. Like numbers refer to like elements throughout. 
         [0029]    Although the following detailed description contains many specifics for the purposes of illustration, anyone of ordinary skill in the art will appreciate that many variations and alterations to the following details are within the scope of the invention. Accordingly, the following embodiments of the invention are set forth without any loss of generality to, and without imposing limitations upon, the claimed invention. 
         [0030]    In this detailed description of the present invention, a person skilled in the art should note that directional terms, such as “above,” “below,” “upper,” “lower,” and other like terms are used for the convenience of the reader in reference to the drawings. Also, a person skilled in the art should notice this description may contain other terminology to convey position, orientation, and direction without departing from the principles of the present invention. 
         [0031]    An embodiment of the invention, as shown and described by the various figures and accompanying text, provides a luminaire  100 . Referring initially to  FIG. 1 , a luminaire  100  according to an embodiment of the present invention is depicted, the luminaire  100  including a base  110 , a lower structure  200 , a prismatic optic  300 , and an upper structure  600 . 
         [0032]    The base  110  of the present embodiment of the luminaire  100  is configured to conform to an Edison screw fitting that is well known in the art. However, the base  110  may be configured to conform with any fitting for light bulbs known in the art, including, but not limited to, bayonet, bi-post, bi-pin, and wedge fittings. Additionally, the base  110  may be configured to conform to the various sizes and configurations of the aforementioned fittings. 
         [0033]    In the present embodiment, the base  110  of the luminaire  100  may include an electrical contact  111  formed of an electrically conductive material, an insulator  112 , and a sidewall  113  comprising a plurality of threads  114 . The plurality of threads  114  may form a threaded fitting on inside and outside surfaces of the sidewall  113 . The electrical contact  111  may be configured to conduct electricity from a light socket. 
         [0034]    Turning to  FIG. 2 , the lower structure  200  may have a lower section  201  defining a first end  202  and an upper section  203  defining a second end  204 . The interface between the lower section  201  and the upper section  202  may define a shelf  206  disposed about a perimeter the lower section  201 . The shelf  206  may include one or more attachment sections  207  at which the prismatic optic  300  may attach to the lower structure  200 . The first end  202  may be attached to the base  110  at the sidewall  113  by any means known in the art, including, not by limitation, use of adhesives or glues, welding, and fasteners. 
         [0035]    Each of the first section  201  and the second section  203  may include a void that cooperates with each other to define a longitudinal cavity  208 . The shape and dimensions of the longitudinal cavity  208  will be discussed in greater detail hereinbelow. The upper section  203  may include a body member  209  having an outside surface  210 . The outer surface  210  may be configured to reflect light incident thereupon. The outer surface  210  may have a reflection coefficient of at least about 0.1, or about 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9, or about 0.91, 0.92, 0.93, 0.94, 0.95, 0.96, 0.97, 0.98, or 0.99, or about 1. In one embodiment, the outer surface  210  may act as a substrate and have a layer of reflective paint applied thereto. The reflective paint may advantageously enhance illumination provided by the light source by causing enhanced reflection of the light prior to reaching the prismatic enclosure  300 , which will be discussed in greater detail below. In another embodiment, the outer surface  210  may have a reflective liner applied thereto. Similarly, the reflective liner may be readily provided by any type of reflective liner which may be known in the art. 
         [0036]    The upper section  203  may further include one or more channels  212  formed in the outer surface  210 . The channels  212  may be configured to align with the attachment sections  207  and run parallel to the longitudinal cavity  208 , facilitating the attachment of the prismatic optic  300  to the lower structure  200 . 
         [0037]    In the present embodiment, the lower structure  200  may be configured to act as a heat sink. Accordingly, portions of the lower structure  200  may be formed of thermally conductive material. Moreover, portions of the lower structure  200  may include fins  214 . In this embodiment, the fins  214  are configured to run the length of the lower section  201  and extend radially outward therefrom. The fins  214  increase the surface area of the lower structure  200  and permit fluid flow between each fin  214 , enhancing the cooling capability of the lower structure  200 . The fins  214  may have a curved vertical profile to emulate the shape of traditional incandescent light bulbs. Optionally, the fins  214  may be configured to conform to the A19 light bulb standard size. Additional information directed to the use of heat sinks for dissipating heat in an illumination apparatus is found in U.S. Pat. No. 7,922,356 titled Illumination Apparatus for Conducting and Dissipating Heat from a Light Source, and U.S. Pat. No. 7,824,075 titled Method and Apparatus for Cooling a Light Bulb, the entire contents of each of which are incorporated herein by reference. 
         [0038]    Furthermore, the lower structure  200  may include interior channels formed in the body member  209 . The interior channels may extend from a first opening  216  in an upper surface  222  of the body member  209  to a second opening  218  in an interior surface  224  of the upper section  203  forming the longitudinal cavity  208 . Air may be permitted to flow through the interior channels, providing additional cooling capability. Alternatively, the lower structure  200  may be formed as a substantially solid structure, not including the various structural aspects intended to increase the cooling capacity as described above. The lower structure  200  may further include a recessed region  220  formed in the upper surface  222  of the body member  209 . The recessed region may extend from the void of the upper section  203  to the outside surface  210 . 
         [0039]    Referring now to  FIG. 3 , a prismatic optic  300  according to an embodiment of the present invention is depicted. In the present embodiment, the prismatic optic  300  may include an upper optic  310  and a lower optic  350 . The upper optic  310  may be attached to the lower optic  350  by any method known in the art, including, but not limited to, threaded coupling, interference fit, adhesives, glues, fasteners, and welding, or combinations thereof. Moreover, in an alternative embodiment, the upper optic  310  and the lower optic  350  may be integrally formed as a single optic. The prismatic optic  300  is configured to define an optical chamber  301 , wherein the optical chamber  301  is configured to permit a light source to be disposed therein. 
         [0040]    The prismatic optic  300  may be formed of any transparent, translucent, or substantially translucent material including, but not limited to, glass, fluorite, and polymers, such as polycarbonate. Types of glass include, without limitation, fused quartz, soda-lime glass, lead glass, flint glass, fluoride glass, aluminosilicates, phosphate glass, borate glass, and chalcogenide glass. 
         [0041]    Each of the upper optic  310  and the lower optic  350  may include a sidewall  312 ,  352  comprising an inner surface  314 ,  354  and an outer surface  316 ,  356 . Each of the outer surfaces  316 ,  356  may comprise a plurality of grooves  318 ,  358  formed thereon. Turning to  FIGS. 4   a - b,  the grooves  318 ,  358  are configured to have substantially straight sides  320 ,  360 , the sides forming alternating peaks  322 ,  362  and valleys  324 ,  364 . The angles formed at the peaks  322 ,  362  and valleys  324 ,  364 , as well as the length of the sides  320 ,  360  may be selectively chosen to alter the refraction of light thereby. 
         [0042]    Returning now back to  FIG. 3 , each of the outside surfaces  316 ,  356  may be configured to have a curvature. The degree of the curvature may be selected according to design standards, such as, a curvature that conforms to an A19 light bulb standard, having a diameter of about 2.375 inches. The curvature may also conform to any other industry standard, including, but not limited to, A15 (about 1.875 inches), A21 (about 2.625 inches), G10 (about 1.25 inches), G20 (about 2.5 inches), G25 (about 3.125 inches), G30 (about 3.75 inches), and G40 (about 5 inches). The preceding are provided for exemplary purposes and are not limiting in any way. 
         [0043]    The lower optic  350  may include one or more protruding members  366  extending radially inward from a first end the inner surface  354 . The protruding members  366  may be configured to pass through the one or more channels  212  to interface with the attachment sections  207 , which are depicted in  FIG. 2 . Each protruding member  366  may be associated with one channel  212  and one attachment section  207 . Each of the protruding members  366  may be attached to an attachment section  207 , thereby attaching the optic  300  to the lower structure  200 . The protruding members  366  may be attached to the attachment sections  207  by any method that can withstand the forces experienced by the luminaire  100 , such as those experienced during installation and removal. Methods of attachment include, but are not limited to, adhesives, glues, welding, and fasteners. Similarly, the upper optic  310  may include protruding members  326  extending radially inward from a first end of the inner surface  314 . The protruding members  326  may be configured to attach to the upper structure  600  described in detail hereinbelow. 
         [0044]    Referring now to  FIG. 5 , each of the inner surfaces  314 ,  354  may include a plurality of generally vertical segments  328 ,  368  and a plurality of generally horizontal segments  330 ,  370 . Each of the generally vertical segment  328 ,  368  may have two ends and may be attached at each end to a generally horizontal segment  330 ,  370 , thereby forming a plurality of prismatic surfaces  332 ,  372 . It is not a requirement of the invention that the generally vertical segments  328 ,  368  be perfectly vertical, nor is it a requirement that the generally horizontal segments  330 ,  370  be perfectly horizontal. Similarly, it is not a requirement of the invention that the generally vertical segments  328 ,  368  be perpendicular to the generally horizontal segments  330 ,  370 . Each of the prismatic surfaces  332 ,  372  may be smooth, having a generally low surface tolerance. Moreover, each of the prismatic surfaces  332 ,  372  may be curved, forming a diameter of the inner surfaces  314 ,  354 . 
         [0045]    The variance of the generally vertical segments  328 ,  368  from vertical may be controlled and configured to desirously refract light. Similarly, the variance of the generally horizontal segments  330 ,  370  from horizontal may be controlled and configured to produce prismatic surfaces  330 ,  370  that desirously refract light. Accordingly, the prismatic surfaces  332 ,  372  may cooperate with the grooves  318 ,  358 , as depicted in  FIGS. 3 and 4   a - b,  to desirously refract light about the luminaire  100  (shown in  FIG. 1 ). 
         [0046]    Referring now to  FIG. 6 , the upper structure  600  of an embodiment of the present invention is depicted. The upper structure  600  may include a body member  602  having an outer surface  604 . The outer surface  604  may be configured to reflect light incident thereupon. The outer surface  604  may have a reflection coefficient of at least about 0.1, or about 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9, or about 0.91, 0.92, 0.93, 0.94, 0.95, 0.96, 0.97, 0.98, or 0.99, or about 1. In one embodiment, the outer surface  604  may act as a substrate and may have a layer of reflective paint applied thereto. In another embodiment, the outer surface  604  may have a reflective liner applied thereto. 
         [0047]    The upper structure  600  may further include a ridge  606 . The ridge  606  may interface with the prismatic optic  300 , thereby constraining the prismatic optic  300  between the upper structure  600  and the lower structure  200 . Furthermore, the ridge  606  may include one or more attachment surfaces  608  configured to facilitate attachment of the upper structure  600  to the prismatic optic  300 , as shown in  FIG. 3 . The protruding members  326  of the upper optic  310  may be attached to the attachment sections  608  by any method that can withstand the forces experienced by the luminaire  100 , such as those experienced during installation and removal. Methods of attachment include, but are not limited to, adhesives, glues, welding, and fasteners. 
         [0048]    The upper structure  600  may further include one or more channels  610  formed in the outer surface  604 . The channels  610  may be configured to align with the attachment sections  608 , permitting the passage of protruding members  326  therethrough and facilitating the attachment of the prismatic optic  300  to the upper structure  600 . 
         [0049]    In the present embodiment, the upper structure  600  may be configured to act as a heat sink. Accordingly, portions of the upper structure  600  may be formed of thermally conductive material. Moreover, portions of the upper structure  600  may include fins  612 . In the illustrated embodiment, the fins  612  are configured to extend from the ridge  606  generally upwards and towards a longitudinal axis of the upper structure  600 . The fins  612  advantageously increase the surface area of the upper structure  600  and permit fluid flow between each fin  612 , enhancing the cooling capability of the lower structure  600 . The fins  612  may have a curved vertical profile to emulate the shape of traditional incandescent light bulbs. Optionally, the fins  612  may be configured to conform to the A19 light bulb standard size. Those skilled in the art will appreciate that the present invention contemplates the use of various configurations of fins to enhance heat dissipation. 
         [0050]    Referring now additionally to  FIG. 7 , the body member  604  may further include an inner surface  614  defining an internal cavity  616 . The internal cavity  616  may be configured to cooperate with the longitudinal cavity  208  of the lower structure  200 , defining a continuous cavity. Furthermore, the body member  602  may include a shelf  617  extending radially inward from the inner surface  614  into the internal cavity  616 . 
         [0051]    As also illustrated in  FIGS. 6-7 , the upper structure  600  may further include a recessed section  618  on the top of the upper structure  600 . The recessed section  618  may include an upper attachment section  620 . The upper attachment section  620  may be configured to attach a housing  900  (described below and illustrated in  FIG. 9 ) thereto. The circuit board will be described in greater detail hereinbelow. The attachment section  620  may be configured to permit attachment by any method known in the art, including, but not limited to, fasteners, such as screw and threads, adhesives, glues, and welding. The upper structure  600  may further include a recessed region  622  formed in a lower surface of the body member  604 . The recessed region  622  may be positioned so as to approximately align with the recessed region  220  of the lower structure  200 . Alternatively, the upper structure  600  may be formed as a substantially solid structure, not including the various structural aspects intended to increase the cooling capacity as described above. 
         [0052]    Referring now to  FIG. 8 , according to an embodiment of the invention, a luminaire including a light source  800  is provided. The present embodiment of the light source  800  employs one or more light emitting elements  802 . The light emitting elements  802  may be disposed within the optical chamber  301  of the prismatic optic  300 , as depicted in  FIG. 3 . 
         [0053]    The light emitting elements  802  may be oriented to emit light that is incident upon the prismatic surfaces  332  of the upper optic  310  as well as the prismatic surfaces  372  of the lower optic  350 , as depicted, for example, in  FIG. 5 . Accordingly, the light emitting elements  802  may be configured to emit light generally radially outward as well as upwards and downwards from the luminaire  100 , as shown in  FIG. 1 . 
         [0054]    According to the present embodiment of the invention, the light source  800  may include a platform  804 . The platform  804  may include an upper surface  806 , a lower surface  808 , and a void  809 , wherein each of the upper and lower surfaces  806 ,  808  are generally flat and configured to permit attachment of the light emitting elements  802  thereto. For example, the light source  800  may include a channel  810  formed into one of the upper surface  806  and the lower surface  808 , or both. The channel  810  may be configured to form a region in the upper surface  806  into which the light emitting elements  802  may be there attached. 
         [0055]    The location of the channel  810  on the upper surface  806  may be selectively chosen. In the present embodiment, the channel  810  is formed generally about the periphery of the upper surface  806 , although the channel  810  may be formed in any part of the upper surface  806 . In some embodiments, a plurality of light emitting elements  802  may be distributed within the channel  810 . Each of the plurality of light emitting elements  802  may be selectively distributed, for example, they may be spaced at regular intervals. In an alternative example, the light emitting elements  802  may be clustered in groups. The configuration of the disposition of the light emitting elements  802  may be selected to achieve a desired lighting profile or outcome. 
         [0056]    The channel  810  may further include an attachment material disposed within the channel  810 . The attachment material may facilitate the attachment of the light emitting elements  802  within the channel  810 . Furthermore, the attachment material may facilitate the operation of the light emitting elements  802 . For example, where the light emitting elements  802  are LEDs, the attachment material may be formed of an electrically conductive material. Furthermore, the attachment material may be configured to include two or more electrical conduits that are isolated from each other, facilitating the operation of the light emitting elements  802 . 
         [0057]    The light source  800  may further comprise a communication section  812  formed adjacent the channel  810 . Accordingly, the communication section  812  may be formed in either of the upper surface  806  and the lower surface  808 , or both. The communication section  812  may contact the channel  810 . Furthermore, the communication section  812  may be formed of an electrically conductive material. Accordingly, the communication section  812  may be in electrically coupled to the channel  810 . 
         [0058]    The communication section  812  may include a first terminal  814  and a second terminal  816 . Each of the first and second terminals  814 ,  816  may be formed of an electrically conductive material, may contact the channel  810 , and further may be electrically coupled to the channel  810 . Furthermore, where the channel  810  may include an attachment section including two or more isolated electrical conduits, the first terminal  814  may be in communication with a first electrical conduit of the attachment section, and the second terminal  816  may be in communication with a second electrical conduit of the attachment section. For example, and not by limitation, the first terminal  814  may be in communication with a power source conduit, and the second terminal may be in communication with a ground conduit. 
         [0059]    Still referring to  FIG. 8 , the first and second terminals  814 ,  816  may each include a pad  818 ,  820  respectively. The pads  818 ,  820  may be configured to facilitate attachment of an electrical communication medium thereto. For example, and not by limitation, the dimensions of the pads may be selectively chosen to permit a wire to be soldered thereto. The pads  818 ,  820  may be disposed approximately adjacent to the void  809 . Moreover, the pads  818 ,  820  may be positioned so as to approximately align with the recessed region  220  of the lower structure  200  and the recessed region  622  of the upper structure  600 . The void  809  may be disposed about approximately the center of the platform  804 . The void  809  may be positioned and dimensioned to approximately align with the longitudinal cavity  208  as shown in  FIG. 1  and the internal cavity  616  as shown in  FIG. 7 , defining a continuous cavity. 
         [0060]    Referring now to  FIG. 9   a , a housing  900  according to an embodiment of the invention is presented. The housing  900  may be configured to be disposed substantially about a power source. The housing  900  may include a base section  910  and a monolithic section  950 . The base section  910  may be configured to attach the housing  900  to the base  110  as shown in  FIG. 1 . Specifically, the base section  910  may include a body member  911  including plurality of threads  912  configured to cooperate with the threads  114  of the base  110 , wherein the threads  114  are functional on both an inside surface and an outside surface of the base  110 . Alternatively, the base section  910  may be attached to the base  110  by other methods, including, but not limited to, adhesives, glues, fasteners, and welding. 
         [0061]    The base section  910  may include an opening (not shown) at a first end  914 . The opening may be configured to have the shape and sufficient dimensions to permit a power source to pass therethrough. The base section  910  may further include a flange  916  extending radially outward from the body member  911 . The base section  910  may still further include a sidewall  918  extending approximately orthogonally from the flange  916 . In one embodiment, the sidewall  918  may be configured to interfere with the fins  214  of the lower structure  200 . In such an embodiment, the housing  900  may be disposed within the longitudinal cavity  208  of the lower structure  200 , and the interference between the sidewall  918  and the fins  214  restricts the translation of the housing  900  beyond the point of that interference. Further, the base section  910  may include one or more ribs  920  that may be attached to the sidewall  918 , the flange  916 , and the monolithic section  950 . 
         [0062]    The monolithic section  950  may be configured as a hollow, generally straight, substantially elongated structure. It may include a first end  952  and a second end  954 , with the first end  952  being adjacent the base section  910  and the second end  954  being substantially apart from the base section  910 . The monolithic section  950  may include one or more sidewalls  956  intermediate the first end  952  and the second end  954 , extending generally upward from the base section  910 . The sidewalls  956  may be attached and continuous, so as to define an internal cavity there between. The dimensions of the internal cavity may be sufficient to permit a power source to be at least partially disposed therein, as depicted in  FIG. 9   b.    
         [0063]    At least one of the sidewalls  956  may include an opening  957  towards the second end  954 . The opening  957  may be configured to facilitate the electrical coupling between a power source and the light source, illustrated in  FIG. 8 , and described in greater detail hereinbelow. 
         [0064]    At least one of the sidewalls  956  may include one or more vents  958 . The vents  958  may be positioned anywhere along the sidewall  956 . In the present embodiment, the vents  958  are positioned substantially toward the first end  952 . The positioning of the vents  958 , as well as their shape and dimensions, may be selected so as to facilitate the flow of air between the internal cavity defined by the sidewalls  956  and the area surrounding the housing  900 . In one embodiment of the invention, the flow of air may increase the cooling capability of the housing  900 , thereby reducing the operating temperature of a power source disposed within the internal cavity defined by the sidewalls  956 . For example, the vents  958  may be positioned adjacent those parts of a power source that generate the most heat, permitting the rapid transportation of air heated by the power source out of the housing  900  and to heat sinks, such as certain embodiments of the upper structure  200  and the lower structure  600 . 
         [0065]    The monolithic section  950  may further include an attachment section  960  located substantially towards the second end  954 . Referring now to  FIG. 7 , the attachment section  960  may be configured to attach to the upper attachment section  620  of the upper structure  600 . The attachment section includes a receiving lumen  962  through which a fastener may be disposed and attached thereto. In the present embodiment, a fastener  624  is disposed through the upper receiving section  620  and into the receiving lumen  962 , attaching to the receiving lumen, thereby fixedly attaching the housing  900  to the upper structure  600 . However, alternative embodiments permit the attachment section  960  to attach to the upper attachment section  920  by any method known in the art, including, but not limited to, adhesives, glues, and welding. 
         [0066]    Referring now to  FIG. 10 , according to an embodiment of the invention, a luminaire including a cap  700  is provided. The cap  700  is configured to cover the recessed section  618  of the upper structure  600 , as depicted in  FIG. 7 . The cap  700  includes a domed section  702  and a plurality of tabs  704  extending generally downward and approximately perpendicular to the domed section  702 . One or more of the plurality of tabs  704  may include a catch  706  disposed on one end of the tab  704 . As shown in  FIG. 7 , the catch  706  may engage with the shelf  617  of the upper structure  600 , thereby removably coupling the cap  700  to the upper structure  600 . 
         [0067]    Referring now to  FIG. 11 , a power source according to an embodiment of the present invention is presented. In the present embodiment, the power source may include a circuit board  1000 . The circuit board  1000  may be configured to condition power to be used by the light emitting elements  802  of the light source  800 . Furthermore, the circuit board  1000  may have a first end  1002  and a second end  1004 , wherein the first end  1002  is positioned generally downward and toward the base  110 , and the second end  1004  is positioned generally upward and toward the upper structure  600 . The circuit board  1000  may be dimensioned to permit at least a portion of the circuit board  1000  to be disposed within the internal void of the housing  900 . 
         [0068]    The circuit board  1000  may include a first electrical contact  1010 . The first electrical contact may be positioned toward the first end  1002  of the circuit board  1000 . The first electrical contact  1010  may be configured to electrically couple with the electrical contact  111  of the base  110 , thereby enabling the first electrical contact  1010  to supply power to the circuit board  1000 . The circuit board  1000  may further include a second electrical contact  1020 . The second electrical contact  1020  may be positioned toward the second end  1004  of the circuit board  1000 . The second electrical contact  1020  may be configured to electrically couple with the pads  818 ,  820  ( 820  not shown) of the light source  800 . The electrical coupling between the second electrical contact  1020  and the pads  818 ,  820  enables the circuit board  1000  to deliver power to the light emitting elements  802 . 
         [0069]    In one embodiment, the electrical contact  111  conducts power from a light fixture that provides 120-volt alternating current (AC) power. Furthermore, in the embodiment, the light emitting elements  802  comprise LEDs requiring direct current (DC) power at, for instance, five volts. Accordingly, the circuit board  1000  may include circuitry for conditioning the 120-volt AC power to 5-volt DC power. 
         [0070]    In a further embodiment, the circuit board  1000  may include a microcontroller. The microcontroller may be programmed to control the delivery of electricity to the light source. The microcontroller may be programmed to, for instance, dim the light emitting elements  802  according to characteristics of the electricity supplied through the electrical contact  111 . 
         [0071]    Referring now to  FIG. 11 , the light emitted from the light emitting elements  802  may cooperate with the prismatic surfaces  332 ,  372  and the grooves  318 ,  358  to refract the emitted light substantially about the luminaire  100 . The prismatic surfaces,  332 ,  372  and the grooves  318 ,  358  may be configured to selectively refract light within desired ranges about the luminaire  100 . Furthermore, the light may be refracted to maintain a uniform intensity within desired ranges about the luminaire  100 . 
         [0072]    It is understood that the angles referred to herein are measured according to a polar coordinate system, wherein the angles are measured from the positive Z-axis directed vertically. Moreover, the intensities referred to are in reference to an intensity of the light emitted by the luminaire  100  within a certain angle range. In the present embodiment of the invention, the reference intensity is an average intensity of light emitted within the range of angles between 0 degrees and 135 degrees. 
         [0073]    Turning now to  FIG. 12 , a graph of ranges of light refraction is presented. Light may be refracted within a first range  1210  about the luminaire. The first range  1210  may include angles within a range between about 0 degrees to about 135 degrees. Furthermore, the light emitted within the first range  1210  may be within about 20%, 10%, 5%, or 1% of the average intensity. 
         [0074]    Light may also be refracted within a second range  1220  about the luminaire  100 . The second range  1220  may include angles within a range between about 135 to about 150 degrees. Furthermore, the light emitted within the second range  1220  may be within about 20%, 10%, 5%, or 1% of the average intensity. Light may also be refracted within a third range  1230  about the luminaire  100 . The third range  1230  may include angles within a range between about 150 degrees to about 180 degrees. Furthermore, the light emitted within the third range  1230  may be within about 20%, 10%, 5%, or 1% of the average intensity. 
         [0075]    Some of the illustrative aspects of the present invention may be advantageous in solving the problems herein described and other problems not discussed which are discoverable by a skilled artisan. 
         [0076]    While the above description contains much specificity, these should not be construed as limitations on the scope of any embodiment, but as exemplifications of the presented embodiments thereof. Many other ramifications and variations are possible within the teachings of the various embodiments. While the invention has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best or only mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. Also, in the drawings and the description, there have been disclosed exemplary embodiments of the invention and, although specific terms may have been employed, they are unless otherwise stated used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention therefore not being so limited. Moreover, the use of the terms first, second, etc. do not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another. Furthermore, the use of the terms a, an, etc. do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item. 
         [0077]    Thus the scope of the invention should be determined by the appended claims and their legal equivalents, and not by the examples given.