Patent Publication Number: US-8523383-B1

Title: Retrofitting recessed lighting fixtures

Description:
RELATED APPLICATION 
     This application claims priority under 35 U.S.C. §119 to U.S. Provisional Patent Application No. 61/306,010, titled “Systems, Methods, and Devices for Retrofitting Recessed Fluorescent Lighting Fixtures,” filed on Feb. 19, 2010, the complete disclosure of which is hereby fully incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     This disclosure relates generally to lighting fixtures and, more particularly, to retrofitting recessed lighting fixtures. 
     BACKGROUND 
     Recent technologies relative to ballasts and light sources are more energy efficient than those used in the past. However, the expense of replacing an entire light fixture previously installed may make taking advantage of such improvements in these technologies cost prohibitive. Recently, efforts have been made to retrofit previously installed light fixtures to provide a less expensive way to take advantage of new lighting technology. 
     Light fixture retrofitting is the practice of replacing or eliminating components in an existing light fixture housing to make the light fixture more energy efficient or change some other performance characteristic of the light fixture. However, the larger the cost of replacement components and longer the installation of a retrofit solution takes, the less likely that retrofit solution will make economic sense for the owner of the previously installed light fixture. 
     Many current retrofitting solutions are relatively crude in design, often requiring lengthy and complex installation with loose parts, which may add to the installer&#39;s difficulty since many of the light fixtures being retrofitted are recessed in a ceiling. Wiring the previously installed fixture is often a difficult task and, sometimes, a hazardous one that could affect the safety of the installer, especially when the fixtures are at high elevation or difficult to reach. Essentially, the pre-existing housing is an upside down box where any installation of a new component into that upside down box brings with it the risk of falling objects. This creates a safety hazard not only for the installer but other individuals in the installation area. Moreover, the more cumbersome the installation, the longer the installation may take and the greater the number of installers needed to complete the installations. Such delay and/or additional installers only add to the expense of retrofitting existing lighting fixtures. 
     SUMMARY 
     A kit may be provided for retrofitting a preexisting recessed light fixture housing mounted in a ceiling plane. The preexisting recessed light fixture housing can include an upper base panel and opposed end walls extending generally downward from the upper base panel. The kit can include first and second mounting brackets that are coupled to the housing, adjacent the opposed end walls. Each mounting bracket can include an electrical socket. The electrical sockets can complete a circuit with a lamp, such as a fluorescent lamp, a linear LED lamp, and/or another lamp, when the lamp is installed between the electrical sockets. 
     The kit also can include a ballast that provides power to the circuit when the kit is installed in the recessed light fixture. The ballast can be configured to be coupled to the upper base panel of the housing. An adhesive can be disposed on a mounting side of the ballast, for provisionally mounting the ballast to the upper base panel of the housing prior to installation of a fastener, which permanently mounts the ballast to the upper base panel of the housing. The fastener may include a captive hardware element, which is pre-installed in the ballast and designed to be movable relative to the ballast only upon application of deliberate force with respect to the captive hardware element. Each mounting bracket also may include one or more captive hardware elements. 
     These and other aspects, features and embodiments of the invention will become apparent to a person of ordinary skill in the art upon consideration of the following detailed description of illustrated embodiments exemplifying the best mode for carrying out the invention as presently perceived. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a more complete understanding of the claimed invention and the advantages thereof, reference is now made to the following description, in conjunction with the accompanying figures briefly described as follows. 
         FIG. 1  is an exploded view of a top-level assembly of a retrofit linear lighting fixture, in accordance with certain exemplary embodiments. 
         FIG. 2  illustrates certain components of an example retrofit “kit,” in accordance with certain exemplary embodiments. 
         FIG. 3  is an exploded view of certain components of the retrofit kit of  FIG. 2 , in accordance with certain exemplary embodiments. 
         FIG. 4  illustrates a mounting bracket subassembly of the retrofit kit of  FIG. 2 , in accordance with certain exemplary embodiments. 
         FIG. 5  illustrates socket location tabs included on the mounting bracket subassembly of  FIG. 4 , in accordance with certain exemplary embodiments. 
         FIG. 6  is a partially exploded view of the mounting bracket subassembly of  FIG. 4 , in accordance with certain exemplary embodiments. 
         FIG. 7  illustrates a bottom view of the mounting bracket subassembly of  FIG. 4 , in accordance with certain exemplary embodiments. 
         FIG. 8  illustrates a view of a head of a self-drilling captive screw of the mounting bracket subassembly of  FIG. 4 , in accordance with certain exemplary embodiments. 
         FIG. 9  illustrates a side view of the self-drilling captive screw of  FIG. 8 , in accordance with certain exemplary embodiments. 
         FIG. 10  illustrates a reflector panel of the retrofit kit of  FIG. 2 , in accordance with certain exemplary embodiments. 
         FIG. 11  illustrates a ballast of the retrofit kit of  FIG. 2 , in accordance with certain exemplary embodiments. 
         FIG. 12 , including  FIGS. 12A ,  12 B, and  12 C, illustrates a diffuser lens and an optional internal baffle, which may be included in the retrofit kit of  FIG. 2 , in accordance with certain exemplary embodiments. 
         FIG. 13  illustrates the diffuser lens of  FIG. 12  installed on a lens end cap, in accordance with certain exemplary embodiments. 
         FIG. 14 , including  FIGS. 14A ,  14 B, and  14 C, illustrates a cross-section of a lens end cap, lens, mounting bracket subassembly, lamp, and socket connection end of a retrofit linear lighting fixture, in accordance with certain exemplary embodiments. 
         FIG. 15  illustrates a cross-section view of a retrofit solution for a parabolic linear lighting fixture, in accordance with certain exemplary embodiments. 
         FIG. 16  illustrates a cross-section view of a retrofit solution for a lensed troffer linear lighting fixture, in accordance with certain exemplary embodiments. 
         FIG. 17  illustrates alternative housing end cap profiles, demonstrating the versatility of the mounting bracket subassemblies of the kit of  FIG. 2 , in accordance with certain exemplary embodiments. 
         FIG. 18  illustrates an exploded view of a retrofit solution for a backlit luminous panel linear lighting fixture, in accordance with certain alternative exemplary embodiments. 
         FIG. 19 , including  FIGS. 19A-191 , depicts a method for retrofitting a recessed light fixture, in accordance with certain exemplary embodiments. 
         FIG. 20  illustrates an installer peeling protective paper from a two sided adhesive tape on a mounting side of a ballast during the retrofitting method of  FIG. 19 , in accordance with certain exemplary embodiments. 
         FIG. 21  illustrates an installer provisionally mounting the ballast against the interior surface of the housing during the retrofitting method of  FIG. 19 , in accordance with certain exemplary embodiments. 
         FIG. 22  illustrates an installer permanently mounting the ballast against the interior surface of the housing during the retrofitting method of  FIG. 19 , in accordance with certain exemplary embodiments. 
         FIG. 23  illustrates an installer inserting the first bracket subassembly during the retrofitting method of  FIG. 19 , in accordance with certain exemplary embodiments. 
         FIG. 24  illustrates an installer attaching the first bracket subassembly of  FIG. 23  to the housing during the retrofitting method of  FIG. 19 , in accordance with certain exemplary embodiments. 
     
    
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     Embodiments of the claimed invention are directed to improved retrofit solutions for recessed light fixtures. In certain exemplary embodiments, a kit for retrofitting an existing light fixture includes mounting brackets, which each include at least one lamp socket, as well as a ballast, which is pre-wired to the sockets. Pre-wiring these components reduces time and expertise required for installation. Each ballast may include an adhesive on a mounting side thereof, for use during the installation process. For example, the installer may provisionally mount the ballast to an interior surface of an existing housing of the fixture using the adhesive and then permanently mount the ballast using one or more fasteners. The fasteners of the kit may include captive hardware, which reduces risk of dropping or losing parts of the kit during installation. 
     In certain exemplary embodiments, the kit includes a reduced total number of parts as compared to previous retrofit solutions. For example, certain exemplary embodiments eliminate the need for an inner reflector by creating a single reflector design that serves as the luminaire reflector while also serving as a ballast and/or splice cover, thereby simplifying installation and reducing overall costs. In addition, the mounting brackets of the kit may include various different possible socket locations, thereby providing flexibility with regard to the number and positioning of the lamps while eliminating the need for an additional socket bracket. The kit may be adapted to work with one, two, or three different lamps, which may be T5 lamps, for example. 
     Although described herein in connection with fluorescent light fixtures, a person of ordinary skill in the art will recognize that the retrofit solutions described herein may be used with other types of light sources, such as linear light emitting diode (“LED”) light sources. For example, instead of including or using a ballast, the retrofit solution can include or use a driver, which controls and/or powers linear LED light sources. Thus, the description herein of lamps and ballast should be understood to include both fluorescent and non-fluorescent lamps and corresponding power components, which may include a ballast, LED driver, and/or other component. 
     In certain exemplary embodiments, the mounting brackets may include one or more bend-out tabs that allow the use of the same bracket in either 2-foot or 4-foot troffer retrofits. In some embodiments of the invention the retrofit design allows these retrofit kits to be used in luminaires as shallow as 3 inches, measured from a ceiling level to a viewing (bottom) end of the housing. 
     The systems and methods described herein may provide several advantages including maximizing energy savings, improving light quality, such as eliminating any ‘cave-like’ effect of traditional parabolic fixtures, as well as improving the overall aesthetics of existing parabolic and lensed troffers. The systems, methods, and apparatuses described herein may also allow for lower cost retrofit solutions, improved light uniformity and area coverage, reduced installation time, easier installation, reduced maintenance and labor costs, pollution reduction, and in some cases, may substitute less energy efficient components of existing recessed fluorescent luminaires with new energy savings components. 
     Turning now to the drawings, in which like numerals indicate like elements throughout the figures, exemplary embodiments are described in detail. As would be recognized by a person of ordinary skill having the benefit of the present disclosure, the claimed invention may be embodied in many different forms and should not be construed as limited to the exemplary embodiments depicted and described herein. 
       FIG. 1  is an exploded view of a top-level assembly of a retrofit linear lighting fixture  100 , in accordance with certain exemplary embodiments. As shown in  FIG. 1 , an existing luminaire housing  102  may be retrofitted with a retrofit kit  105 . The existing luminaire housing  102  includes a frame having a top and first and second side ends that collectively define an opening in which other components of the lighting fixture  100  are disposed.  FIGS. 2 and 3  illustrate certain components of the fluorescent retrofit kit  105 , in accordance with certain exemplary embodiments. 
     With reference to  FIGS. 1-3 , the kit  105  includes mounting bracket subassemblies  104 , a splice cover  106 , at least one ballast  108  (or other power component, such as an LED driver), a reflector panel  110 , and a diffuser lens  112 . In certain exemplary embodiments, one or more components of the kit  105  may not be included or may be optional components of the kit  105 . For example, the splice cover  106  may not be needed in certain embodiments where the power wire is 18 AWG solid or if the existing housing  102  already has a splice cover (subject to regional interpretations of National Electric Code “NEC” requirements). 
     In certain exemplary embodiments, certain components of the kit  105  are pre-wired, thereby avoiding the need for wiring between the components as part of installation of the kit components. For example, the ballast(s)  108  and sockets  205  of the bracket subassemblies  104  are pre-wired together, with one or more electrical connectors  210 , such as quick connectors, which can mate with one or more corresponding connectors (not shown) in the existing housing  102  or installation site to close an electrical circuit, which includes the ballast(s)  108 , sockets  205 , and lamps  305  ( FIG. 3 ) installed between the sockets  205 . Pre-wiring these components allows for a more efficient installation process because the installer can complete some or all required electrical connections for the light fixture  100  merely by snapping, sliding, or otherwise mating together pairs of pre-installed connectors  210 . 
     In certain exemplary embodiments, this pre-wiring feature may allow for safe and efficient installation of the kit  105  by less skilled installers than are traditionally required for light fixture retrofitting. For example, because the installer may not have to wire together any electrical connections, as in traditional retrofitting solutions, the installer may not require any specialized electrical training. Thus, in addition to saving installation time, this solution may allow for reduced labor costs associated with hiring less skilled installers. 
     During installation, the ballast(s)  108  and bracket subassemblies  104  may be carried by the installer with one hand, leaving the other hand available to grab a ladder or portable drill, for example. In certain exemplary embodiments, an adhesive  220 , such as a pressure sensitive, double-sided tape, a transfer adhesive, Velcro, and/or a mastic, may be located on a mounting side of each ballast  108  (or another retrofit kit component) as a temporary means for attaching the ballast(s)  108  to the existing housing  102 . In addition, or in the alternative, the installation may involve placing an adhesive on the existing housing  102 , for mating with the ballast  108  (or other retrofit kit component). In certain alternative exemplary embodiments, the installer may attach the adhesive  220  to the mounting side of the ballast(s)  108  as part of the installation process, instead of receiving the kit  105  with the adhesive  220  attached to the ballast(s)  108 . 
     Provisional attachment of the ballast  108  (or other component) may free up the installer&#39;s hands for other installation requirements. For example, the installer may provisionally mount the ballast(s)  108  to the existent housing  102  via the adhesive  220  and then have free hands to turn and pick up a drill or other tool for completing a permanent installation of the ballast(s)  108  into the existent housing  102 . The position of the installed ballast  108  (or other component) within the existing housing  102  may depend upon a variety of factors, including the size of the ballast  108 , the length of the wires between the ballast  108  and each socket  205  and/or the power source for the fixture  100 , etc. For example, the ballast  108  may be substantially centrally disposed between the sockets  205  in certain exemplary embodiments. 
     In certain exemplary embodiments, the ballast(s)  108  and/or other components of the kit  105  may include captive hardware features, such as captive screws, nails, bolts, clips, and/or another captive fastener means. Each item of captive hardware includes a fastener which is incorporated into a corresponding ballast  108  or other component such that it is fixed to the ballast  108  or other component. While the captive hardware is movable for installation purposes, the captive hardware is not readily removable from its corresponding ballast  108  or other component. Using captive hardware reduces the risk of losing fasteners or the need to pick up dropped fasteners as an additional delay to a successful installation. 
     For example, captive hardware may be incorporated on the bracket subassemblies  104 , ballast(s)  108 , the reflector panel  110 , the splice cover  106 , and/or the diffuser lens  112 , for use in attaching one or more of these components to another component, the housing  102 , and/or another surface. In certain exemplary embodiments, the same type of captive hardware (e.g., screws or other fasteners) may be used wherever possible to reduce the number of different parts, thereby reducing kit  105  complexity, kit  105  manufacture/assembly time, and related expense. However, a person of ordinary skill in the art will recognize that any combination of the same or different fasteners may be used in various exemplary embodiments. 
       FIG. 4  illustrates the bracket subassembly  104 , in accordance with certain exemplary embodiments. With reference to  FIGS. 1-4 , the bracket subassembly  104  includes side reflector guides  402 , a lens end cap  404 , and sockets  205 . As shown in  FIG. 4 , the side reflector guides  402  include substantially elongated members  402   a  that have curved profiles that correspond to the curved shape of the ends  110   a  of the reflector panel  110 . Thus, when the reflector panel  110  is installed in the fixture  100 , the side reflector guides  402  may support and add significant longitudinal stiffness to the reflector panel  110 . For example, the ends  110   a  of the reflector panel  110  can sit on the reflector guides  402  when the reflector panel  110  is installed in the fixture  100 . The side reflector guides  402  also control the shape (e.g., the parabolic shape shown in  FIGS. 3-4 ) of the reflector panel  110 , for increased efficiency and/or illumination uniformity. 
     In certain exemplary embodiments, the side reflector guides  402  also can cover up any assembly gaps between ends of the reflector panel  110  and the ends of the bracket subassemblies  104  and provide a visual (or cosmetic) seal along the side edges of the reflector panel  110 . For example, the assembly gaps may exist when the ends of the bracket subassemblies  104  are installed in different types of enclosures. Although the gaps would not physically be covered by the side reflector guides  402 , the impression would be that no gap exists because the reflector panel  110  ends would “blend” with the side reflector guides  402  and provide a visually continuous seam. 
     The side reflector guides  402  and lens end cap  404  are coupled to a bracket  405  of the assembly  104 , which extends substantially perpendicular to the longitudinal axis of the reflector panel  110  and lamps  305  ( FIG. 3 ) of the fixture  100 . Installation of an exemplary bracket subassembly (which may be substantially similar to the subassembly  104 ) within a fixture (such as fixture  100 ) is illustrated in  FIGS. 23 and 24 , which are described below. In certain exemplary embodiments, the side reflector guides  402  and/or lens cap  404  include injection molded materials that do not require additional hardware to be installed to the bracket  405 . For example, as best seen in  FIG. 5  described below, the side reflector guides  402  depicted in  FIG. 4  include flexible features  407  like a “hook” that would bend and snap in while pressed into a corresponding hole  409  in the bracket  405 . In some embodiments they match the color of the inner/outer reflector (e.g., white). As best seen in  FIGS. 6 and 16  described below, the side reflector guides  402  may include a built-in channel  605  ( FIG. 6 ) for an alternative design that includes a backlit luminous panel. 
       FIG. 5  illustrates socket location tabs  500  included on the bracket  405 , in accordance with certain exemplary embodiments. In the exemplary embodiment shown in  FIG. 5 , the socket locations  500  are marked using visible stamping numbers and/or letters. These locations may be selected depending on the fixture size and the number of lamps to be utilized in the retrofit solution, and the selected locations revealed by bending out the appropriate tabs  500  sometime prior to installation or even bending out the appropriate tabs  500  on the assembly line during the kit manufacturing process. 
     In the exemplary embodiment depicted in  FIG. 5 , tabs  505  are bent out of the bracket  405 . Although depicted in  FIG. 5  as remaining attached to the bracket  405  after being bent out, a person of ordinary skill in the art will recognize that the bent out tabs  505  may snap out or otherwise separate from the bracket  405  in alternative exemplary embodiments. Bending and/or removing the tabs  500  creates an opening for the sockets  205  to be inserted in the bracket  405 , as illustrated in  FIG. 4 . For example, each socket  205  may snap into the bracket  405 , in a position substantially aligned with the opening formed from bending out the tab  500  corresponding to the socket  205 . For instance, some bend-out tab(s)  500  on the bracket  205  may be for two-by-two foot troffers and other bend-out tab(s)  500  may be for two-by-four foot troffers. 
       FIG. 6  illustrates an exploded view of the bracket subassembly  104 , in accordance with certain exemplary embodiments. With reference to  FIGS. 1-6 , the bracket subassembly  104  includes a bracket  405 , side reflector guides  402  with snap-in plastic features  407  for coupling to the bracket  405 , a lens cap  404 , self tapping screws  604  for coupling the lens cap  404  to the bracket  405 , and self-drilling captive screws  612  and/or (fastener-receiving) holes  610  for installing the bracket subassembly  104  in a light fixture housing, such as the existent housing  102  depicted in  FIG. 1 . In certain exemplary embodiments, a profile of the bracket subassembly  104  or the bracket  405  (or one or more other portions of the bracket subassembly  104 ) may be universal to fit many types of pre-existing fixture housings. Moreover, in some example embodiments of the invention, the socket configuration in the mounting bracket may be adjusted in the field to adapt for alternative numbers and arrangements of lamps (such as between 1, 2, and 3 lamps), for added flexibility in achieving desired light levels in various retrofit solutions. This versatility in the bracket design simplifies the process of manufacturing brackets for retrofit kit solutions and avoids the need for using a variety of tooling, thereby further reducing manufacturing costs. 
     In certain exemplary embodiments, the bracket  405  may include a pre-painted sheet metal bracket. Because it requires no in-plant painting either before or after fabrication, pre-painted steel sheet eliminates the manufacturer&#39;s capital burden for providing or using paint facilities as well as paint-line costs associated with the preparation, handling, spraying, and baking or drying operations. In addition, the use of pre-painted steel sheet eliminates the costs of meeting stringent air-quality standards and paint-chemicals disposal requirements. 
       FIG. 7  illustrates a bottom view of the bracket subassembly  104 , in accordance with certain exemplary embodiments. In particular,  FIG. 7  shows more clearly the self drilling captive screws  612  for installing the bracket subassembly  104  in a light fixture housing, such as the existing housing  102  depicted in  FIG. 1 .  FIG. 8  illustrates a view of a head  612   a  of a self drilling captive screw  612 , in accordance with certain exemplary embodiments.  FIG. 9  illustrates a side view of the self drilling captive screw  612 , in accordance with certain exemplary embodiments. 
     With reference to  FIGS. 7-9 , the self drilling captive screws  612  are incorporated into the bracket  405  such that they won&#39;t fall out during installation. In other words, they are “captive” in the bracket  405  prior to and throughout installation. For example, as best seen in  FIG. 9 , the self drilling captive screw  612  may include a non-threaded portion  612   c  flanked between threaded portions  612   a  and  612   b . Prior to installation, a portion of the bracket  405  may rest around the portion  612   c , substantially between the threaded portions  612   a  and  612   b  so that the portion of the bracket  405  is sandwiched between the threaded portions  612   a  and  612   b . Thus, the bracket  405  and screw  612  are not generally movable absent a deliberate force, which is used to advance the screw  612  for installation purposes. 
     Including such captive hardware can eliminate the risk of dropping or losing hardware before or during the installation process. Each screw  612  includes a “drill bit-style” point  612   b  that, upon positive rotation of the screw  612  relative to an installation surface (such as a ceiling or housing), drills its own pilot hole in the installation surface. Thus, the installer may simply rotate the screw  612  without first having to drill a pilot hole in the installation surface, reducing time and effort required for installation. As illustrated in  FIG. 7 , prior to installation of the screw  612 , the end  612   b  is disposed substantially below outer, interfacing edges (including, e.g., edge  705 ) of the bracket  405  so that, when placing the bracket  405  against its installation surface, only the interfacing edges of the bracket  405  touch the installation surface. Thus, the screw  612  does not inhibit a press fit of the bracket  405  against the installation surface. 
     In certain exemplary embodiments, each screw  612  is installed in the bracket  405  by applying 1-2 rotations to the screw  612  coupled with some axial force. Once the screw  612  is in the non-threaded portion  612   c , the axial force is stopped, keeping the screw  612  from advancing more than the desired amount. During installation, the installer applies a torque to the screw head  612   a  and an axial force to create a hole using the self drilling screw tip  612   b , in the installation surface (such as ends of the housing  102 ). Unless the hole is drilled in the installation surface, the screw  612  rotates in the bracket hole but doesn&#39;t advance relative to the bracket hole. The installer applies the axial force to make the screw  612  advance and tighten the bracket  405  to the installation surface. 
     In certain exemplary embodiments, each screw  612  is formed by pressing one or more shaped dies against a blank (cylinder) while the dies and/or blank rotate. The dies contact the blank when forming the threads. The contact is removed for at least one or two rotations so that the threads are not formed in the non-threaded portion  612   c.    
       FIG. 10  illustrates the reflector panel  110 , in accordance with certain exemplary embodiments. With reference to  FIGS. 1-3  and  10 , the reflector panel  110  includes one or more members with a reflective surface formed on one or both sides, or coupled thereto, for reflecting light from the lamps  305  of the fixture  100 . In certain exemplary embodiments, the reflector panel  110  is sized to fit troffer housings as shallow as 3 inches. 
     While the locations of the mounting bracket subassemblies  104  within the fixture are roughly set by the existing features of a fixture housing  102 , the reflector panel  110  may set the spacing of the other fixture components more precisely. Captive screws  1002  in the reflector panel  110  are installed in extruded holes of a socket plate of each bracket subassembly  104 . The distance between the socket plates is set primarily by the reflector panel  110  as a minimum distance. The distance between the bracket subassemblies  104  may be adjusted by moving the screws  1002  from round holes in which they are disposed in  FIG. 10  (where they are installed by factory) into oblong holes  1005  of the reflector. 
     As shown in the embodiment of  FIG. 10 , the reflector panel  110  may be of one-piece construction. This construction simplifies the manufacturing process and tooling for creating the reflector panel  110 . Further, the reflector panel  110  may be made from a wide variety of materials and highly reflective for increased light efficiency (e.g., painted sheet metal or highly reflective plastic sheet). In certain exemplary embodiments, the reflector panel  110  may provide a slight pre-load to reduce vibrations that may be associated with the large surface of the reflector panel  110  when the reflector panel  110  is installed. The reflector can be flexed by the installer and, when released, be trapped between the side reflector guides  402  and lens  112  such that it cannot return to its free state. This is beneficial because the pre-load would keep the reflector tight in place as a constrained spring. Moreover, for some embodiments, vibrations may be drastically reduced by elastic material properties of the reflector panel  110 . As best seen in  FIG. 10 , opposite ends of the reflector panel  110  include flanges  1004 . By changing the formed flange&#39;s  1004  direction and/or size, the reflector panel  110  can allow air flow into the fixture. This may be useful for retrofitting air handling/air return fixtures as well as standard fixtures. Further, the reflector panel  110  and/or the formed flanges  1004  may cover unwanted gaps or black brackets of existing housings. 
     As for the installation of the reflector panel  110 , the reflector panel  110  may be captured under the lens end caps  404  and fixed in place with at least one fastener  1002  (e.g., screws, bolts, or other fasteners), which may include captive hardware  1002 . For example, the reflector panel  110  may be positioned within the fixture and secured to the ballast  108  via the fastener(s)  1002 . In certain exemplary embodiments, the reflector panel  110  includes clearance notches  1010  that allow the installer to install the reflector panel  110  while the lens end caps  404  are installed on the bracket subassemblies  104 . By sliding the reflector panel  110  above the lens end caps  404  and under the side reflector guides  402  and combined with the pre-load of the reflector panel, there is a partial capture of the reflector panel  110  in the housing enclosure  102 . Thus, the installer can take both hands off the reflector panel  110  without any risk of falling objects and use one hand to pick up the drill and the other one to position the reflector  110  more accurately or simply to hold onto a ladder. Captive hardware  1002  on the panel  110  may reduce installation time and improve the ease of installation for the installer. Further, in some embodiments, the reflector panel  110  may be of a universal design to lay-in lensed and/or louver lay-in troffers. 
       FIG. 11  illustrates the ballast  108 , in accordance with certain exemplary embodiments. As shown in  FIG. 11 , the ballast  108  may have captive hardware  1102  (clips, screws, or other fastener) for ease of installation. In certain exemplary embodiments, the captive hardware  1102  may be re-used during new ballast replacement or maintenance. In other words, the captive hardware  1102  clips and/or screws can be removed from the ballast  108  and installed on another ballast  108  (if maintenance occurs), making that new ballast  108  replacement easy to install upside down into the housing  102  ( FIG. 1 ). 
     In certain exemplary embodiments, there is no need for a ballast tray (which typically holds ballasts in conventional retrofit solutions). For example, when using independently mounted brackets  405  and an adhesive  220  (such as double-sided tape) to hold the ballast(s)  108  while installing the kit  105 , a ballast tray may not be required. UL compliance may be maintained with installation per the applicable installation instructions. 
       FIG. 12  illustrates the diffuser lens  112  and an optional internal baffle  1202 , which may be included in the retrofit kit  105 , in accordance with certain exemplary embodiments.  FIG. 13  illustrates the diffuser lens  112  installed on the lens end cap  404 , in accordance with certain exemplary embodiments. With reference to  FIGS. 1-6  and  12 - 13 , the diffuser lens  112  includes an optically transmissive or clear, refractive or non-refractive material (not shown) that provides environmental protection for the lamps  305  and other internal components of the light fixture  100  while also transmitting light from the lamps  305  into a desired environment. For example, the lens  112  may include a combination of clear and frosted materials for different light levels. In some embodiments, the lens  112  may be made of an acrylic material (e.g., extruded or co-extruded acrylic) for longer life, especially under UV exposure from the fluorescent lamps  305 . 
     In certain exemplary embodiments, the lens  112  includes one or more snap in features  1204  that allow the lens  112  to be easily removed and installed. For example, as best seen in  FIG. 13 , each snap in feature  1204  may have a snap-fit engagement with an edge of the lens end cap  404 . Each snap in feature  1204  protrudes from a main body  112   a  of the lens  112 , which is flexible to allow the feature  1204  to move relative to the lens end cap  404 . Although depicted in  FIG. 13  as extending substantially perpendicularly from the main body  112   a , a person of ordinary skill in the art will recognize that each snap in feature  1204  may extend at various different angles relative to the main body  112   a  in certain alternative exemplary embodiments. The snap in features  1204  can allow for efficient and easy re-lamping of the light fixture  100 . 
     In certain exemplary embodiments, an optional internal louver/baffle  1202  may fit inside the lens  112 , trapped between mounting ‘feet’ (or baffle capture channels)  1206  for one-step, simple installation. An internal baffle  1202  can be easier to handle because it will stay with the lens  112  while re-lamping. In the embodiment shown in  FIG. 12 , the optional baffle  1202  is an injection molded part and made out of two segments that may be welded together for a four foot long fixture and one piece for a two foot long fixture. In the embodiment shown in  FIG. 12 , micro-prisms are included on the inner surface  1208  of the lens  112  for uniform light distribution, while the outer surface  1210  of the lens  112  is smooth, facilitating ease of cleaning and upkeep. A person of ordinary skill in the art will recognize that the baffle  1202  may have other manufacturing and size characteristics in alternative exemplary embodiments. 
     The lens end cap  404  (best seen in  FIG. 13 ) can connect to (or capture) a variety of lenses via a positive lens capture or locking portion  1304  of the end cap  404 . The locking portion  1304  includes a substantially angled member, which resists movement of the snap in feature  1204  relative to the end cap  404 . As shown in the embodiment of  FIG. 13 , a lens  112  may be easily installed or removed from the end cap  404  using finger pressure. 
       FIG. 14  illustrates a cross-section  1400  of the lens end cap  404 , lens  112 , mounting bracket subassembly  104 , lamp  305 , and socket  205  connection end of a fluorescent retrofit lighting fixture  100 , in accordance with certain exemplary embodiments. As shown in  FIG. 14 , the (potentially injection molded) end cap  404  may act as a light leak cover  1402  and a support for the lens  112 , and in some embodiments, for an optional baffle. 
       FIG. 15  illustrates a cross-section view of a retrofit solution  1500  for a parabolic fluorescent lighting fixture, in accordance with certain exemplary embodiments. As shown in  FIG. 15 , a retrofit kit embodiment as described herein may be used with both shallow troffers and deep parabolic housings of different shapes. 
       FIG. 16  illustrates a cross-section view of a retrofit solution  1600  for a lensed troffer fluorescent lighting fixture, in accordance with certain exemplary embodiments. Typically the lensed troffer retrofit solution  1600  would be for retrofitting a 3-inch deep troffer. However, a person of ordinary skill in the art would recognize that the solution  1600  may be used in connection with troffers of various different sizes or depths. 
       FIG. 17  illustrates alternative housing end cap profiles  1702 ,  1704 , and  1706 , demonstrating the versatility of the mounting bracket subassemblies  104 , in accordance with certain exemplary embodiments of the invention. 
       FIG. 18  illustrates an exploded view of a retrofit solution  1800  for a backlit luminous panel fluorescent lighting fixture, in accordance with certain alternative exemplary embodiments. The construction for the retrofit solution  1800  is similar to other embodiments of the invention except the lamps  305  sit above one or more translucent side lenses  1806  for a backlighting effect. An inner reflector  1802  may also be provided for increased efficiency and uniformity. The translucent side lenses  1806  may be located by the same side reflector guides. As shown in  FIG. 18 , this backlighting effect may be accomplished with the sockets  205  installed inverted from their configuration in other embodiments of the invention. 
       FIG. 19  depicts a method for retrofitting a recessed light fixture, in accordance with certain exemplary embodiments. In step  1905 , an installer removes an existing door frame  2002  from an existing recessed lighting fixture  2000  (which may be substantially similar or different than the fixture  100  described above). If the fixture  2000  does not include a door frame  2002 , the method  1900  may instead begin at step  1910 , where the installer removes each lamp  2003  from the fixture  2000 , as well as a gear tray  2005 , if any, of the fixture  2000 . In step  1915 , the installer removes each ballast  2007  and bracket assembly  2009  (including sockets) from the fixture  2000 . Upon removing each of these components, the only feature remaining (in the ceiling) from the fixture  2000  is the housing  2008  of the fixture  2000  (which may be substantially similar to or different than the housing  102  described above). 
     In step  1920 , the installer installs each ballast  2007  (which may be substantially similar to or different than the ballast  108  described above). As described above, this step  1920  may involve, for each ballast  2007 , provisionally attaching the ballast  2007  to the housing  2008  via an adhesive, such as a double-stick tape, and then permanently attaching the ballast  2007  via one or more captive hardware elements.  FIGS. 20-22  illustrate installation of the ballast  2007 , in accordance with certain exemplary embodiments. In  FIG. 20 , an installer is peeling protective paper from a two-sided adhesive tape  2010  on a mounting side of the ballast  2007 . In  FIG. 21 , the installer presses the mounting side of the ballast  2007  against the interior surface of the housing  2008 , provisionally adhering the ballast  2007  to the housing  2008  via the tape  2010 . In  FIG. 22 , the installer permanently mounts the ballast  2007  to the housing  2008  via one or more captive hardware elements  2205 . 
     Returning to  FIG. 19 , in step  1925 , the installer installs a first bracket subassembly  2015  (which may be substantially similar to or different from the subassembly  104  described above). As set forth above, this step  1925  may involve actuating one or more captive hardware features to secure the bracket subassembly  2015  to an end wall of the housing  2000 . For example, each captive hardware feature can include a self drilling captive screw, such as the screw  612  depicted in  FIGS. 6-9 .  FIGS. 23-24  illustrate installation of the first bracket subassembly  2015 , in accordance with certain exemplary embodiments. In  FIG. 23 , the installer inserts the first bracket subassembly  2015  between the housing  2008  and a ceiling grid  2305  and against one end wall of the housing  2008 . In  FIG. 24 , the installer attaches the bracket subassembly  2015  to the end wall of the housing  2008  using pre-installed self-drilling captive screws  2310 . 
     Returning to  FIG. 19 , in step  1930 , the installer repeats the procedure of step  1925  to install a second bracket subassembly  2015  against an opposing end wall of the housing  2008 . As set forth above, installing the bracket subassemblies  2015  may involve electrically coupling together sockets (which may be substantially similar to or different than the sockets  205  described above) in the bracket subassemblies  2015  with the ballast(s)  2007  and/or electrically coupling ballast(s)  2007  with a power supply for the light fixture via one or more electrical connectors, such as the connectors  210  depicted in  FIG. 3 . 
     In step  1935 , the installer installs a reflector  2020  (which may be substantially similar to or different than the reflector  110  described above) in the housing  2000  by coupling opposing edges of the reflector  2020  to the bracket subassemblies  2015 . The reflector  2020  may be substantially similar to or different from the reflector panel  110  described above. In certain exemplary embodiments, the reflector  2020  serves the additional purpose of a wire/ballast cover. In some embodiments, re-lamping may be done without removing the reflector  2020  and if so, may be done so in compliance with Underwriters Laboratories (UL) requirements. 
     In step  1940 , the installer installs one or more lamps  2030  in the fixture by connecting the lamps  2030  to sockets in the bracket subassemblies  2015 . As described above, this step may involve selecting and bending socket tabs (such as tabs  505  in  FIG. 5 ) to select appropriate sockets for the lamps  2030 . In step  2035 , the installer installs a lens  2035  (which may be substantially similar to or different from the lens  112  described above). For example, the installer may install the lens  2035  by snapping ends of the lens  2035  in place, as described in connection with  FIG. 13  above. 
     Although specific embodiments of the invention have been described above in detail, the description is merely for purposes of illustration. It should be appreciated, therefore, that many aspects of the invention were described above by way of example only and are not intended as required or essential elements of the invention unless explicitly stated otherwise. Various modifications of, and equivalent steps corresponding to, the disclosed aspects of the exemplary embodiments, in addition to those described above, can be made by a person of ordinary skill in the art, having the benefit of this disclosure, without departing from the spirit and scope of the invention defined in the following claims, the scope of which is to be accorded the broadest interpretation so as to encompass such modifications and equivalent structures.