Abstract:
A method and system for providing an array of illumination modules is disclosed. A modular illumination system can comprise a one-dimensional array, a two-dimensional array, or other shapes and arrangements of the illumination modules. Adjacent illumination modules in the array can be attached to one another via a system of connectors. Each illumination module can comprise at least two connectors, one feeding electricity to a neighboring illumination module and one receiving electricity from a power source. The power source can comprise another neighboring illumination module or a power supply circuit that feeds the array of illumination modules or a subset of illumination modules in the array. Each illumination module can comprise a circuit board, at least one LED, and an optical system that manages light.

Description:
RELATED APPLICATIONS 
     This application claims priority under 35 U.S.C. §119 to U.S. Provisional Patent Application No. 61/510,346, filed Jul. 21, 2011, titled “Method and System for Providing an Array of Modular Illumination Sources.” The foregoing application is hereby incorporated herein in its entirety. This application also incorporates herein by reference in its entirety the disclosure in U.S. Pat. No. 7,674,018, issued Mar. 9, 2010. 
    
    
     FIELD OF THE TECHNOLOGY 
     The present technology relates to illumination systems and more specifically to an array of illumination modules, wherein each module can include a light emitting diode, an associated optical system that manages light from the diode, and a housing. 
     BACKGROUND 
     Light emitting diodes (LEDs) are useful for indoor and outdoor illumination, as well as other applications. Many such applications would benefit from improved technology for producing uniform LED illumination. 
     A need exists for a system of modular LED units that can be readily integrated with one another to provide a one- or two-dimensional array with the number of units in the array selected according to parameters of a specific installation or application. A need further exists for a system that can distribute electrical power among modular LED units in such an array. A need further exists for a system that can manage light from each LED unit in the array so the array provides uniform, consistent, and/or ambient lighting. A capability addressing one or more of such needs, or some other related deficiency in the art, would support effective deployment of LEDs for lighting and other applications. 
     SUMMARY 
     The present technology can support an array of modular light sources providing uniform illumination for an area, for example mounted from a ceiling to illuminate a MOM. 
     In one aspect of the present technology, a modular illumination system comprises an array of illumination modules. The array can be a two-dimensional array or a one-dimensional array. Adjacent illumination modules in the array can be attached to one another via a system of connectors. Each illumination module can comprise at least two connectors, one feeding electricity to a neighboring illumination module and one receiving electricity from a power source. The power source can comprise another neighboring illumination module or a power supply circuit that feeds the array of illumination modules or a subset of illumination modules in the array. Each illumination module can comprise a respective enclosure that houses a circuit board, at least one LED, and an optical system that manages light. The optical system can comprise a first lens that receives light from the LED and a diffuser and/or a second lens that processes light received from the first lens. The first or second lenses can comprise a Fresnel lens. 
     In another aspect, a modular illumination system comprises an array of illumination modules. Each illumination module in the array can comprise a circuit board on which is mounted a light emitting diode. A lens can be mounted over the light emitting diode. A concave reflector can be disposed adjacent to the lens. The concave reflector can comprise a cavity that receives light from the lens, a reflective surface lining the cavity, and an aperture opposite the lens. The concave reflector also can have a diffuser placed over the aperture. 
     In yet another aspect, a modular illumination system comprises an array of illumination modules. An illumination module in the array can comprise a circuit board on which is mounted a light emitting diode. The circuit board can have a first electrical connector attached to one edge and a second electrical connector attached to another edge. The illumination module can further comprise an optic oriented to receive light from the light emitting diode. A first electrical connector of one illumination module of the array can connect to a second electrical connector of another illumination module in the array. 
     The foregoing discussion of illumination systems is for illustrative purposes only. Various aspects of the present technology may be more clearly understood and appreciated from a review of the following disclosure, including the text, drawings, and claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein: 
         FIG. 1  is a perspective view of a modular illumination element in accordance with an exemplary embodiment of this disclosure; 
         FIG. 2  is a perspective view of an array of modular illumination elements in accordance with an exemplary embodiment of this disclosure; 
         FIG. 3  is a perspective view of an array of modular illumination elements in accordance with an exemplary embodiment of this disclosure; 
         FIG. 4  is a perspective exploded view of an array of modular illumination elements in accordance with an exemplary embodiment of this disclosure; 
         FIG. 5  is a perspective view of an array of modular illumination elements in accordance with another exemplary embodiment of this disclosure; 
         FIG. 6  is a perspective view of an array of modular illumination elements in accordance with another exemplary embodiment of this disclosure; 
         FIG. 7  is an exploded perspective view of an array of modular illumination elements in accordance with another exemplary embodiment of this disclosure; 
         FIG. 8  is an exploded view of a modular illumination element in accordance with another exemplary embodiment of this disclosure; 
         FIG. 8A  is another exploded view of a modular illumination element in accordance with another exemplary embodiment of this disclosure. 
         FIG. 9  is a perspective view of a modular illumination element in accordance with another exemplary embodiment of this disclosure; 
         FIG. 10  is a perspective view of an array of modular illumination elements in accordance with another exemplary embodiment of this disclosure; 
         FIG. 11  is an illustration of an illumination pattern; and 
         FIG. 12  is an illustration of an illumination pattern in accordance with an exemplary embodiment of this disclosure. 
     
    
    
     The drawings illustrate only exemplary embodiments and are therefore not to be considered limiting of its scope, as the disclosure may admit to other equally effective embodiments. The elements and features shown in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the exemplary embodiments. Additionally, certain dimensions or positioning may be exaggerated to help visually convey such principles. In the drawings, reference numerals designate like or corresponding, but not necessarily identical, elements. 
     DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     The exemplary embodiments are directed to illumination modules that can be assembled in a variety of different shaped arrays. It should be understood that the embodiments described herein can be applied to the construction of various types of light modules, such as those described in U.S. Pat. No. 7,674,018 referenced at the beginning of this patent application and incorporated herein. It will be understood that the devices taught in U.S. Pat. No. 7,674,018 referenced above could be modified to be used in the form of the LED modules described herein. 
     Exemplary embodiments now will be described more fully hereinafter with reference to the accompanying drawings. This disclosure may, however, be embodied in many different forms and should not be construed as limited to the exemplary embodiments set forth herein; rather, these exemplary embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to persons having ordinary skill in the art. Like numbers refer to like, but not necessarily the same, elements throughout. 
     Referring now to  FIG. 1 , an exemplary illumination module  100  is illustrated. Modular illumination element  100  comprises a heat sink  105  attached to a printed circuit board  110 , the printed circuit board having mounted thereon four LEDs, two of which,  111  and  112 , are visible in  FIG. 1 . As is known to those skilled in the art, any one of a variety of fasteners and adhesives can be used to attach the heat sink  105  and the printed circuit board  110 . In the exemplary embodiment illustrated in  FIG. 1 , the heat sink  105  comprises a series of fins, some of which are shorter than others to form a recessed area  107  for mounting a power supply (not shown). In alternate embodiments, a power supply can be mounted in other locations. 
     The heat sink  105  is coupled to rails  115  and  120 . Heat sink  105  can be coupled to rails  115  and  120  using any of a variety of fasteners including screws, pins, and latches. Rail  115  comprises internal channels  116  and  117  and rail  120  comprises internal channels  121  and  122 . In alternate embodiments, the rails can have greater or fewer channels. In the example modular illumination element  100 , internal channel  116  and internal channel  121  accommodate an optical element  145  which slides along the channels and which comprises four Fresnel lenses. Each of the four Fresnel lenses is aligned with one of the four LEDs mounted on the printed circuit board  110 . As shown in the example embodiment of  FIG. 1 , internal channels  117  and  122  can accommodate other optical elements such as a diffuser  128 . Rails  115  and  120  also comprise external channels  118  and  123 . External channels  118  and  123  can accommodate screws or other fasteners for attaching to a light fixture or other structure. 
     Referring now to  FIG. 2 , an exemplary array of illumination modules attached to a fixture  200  is illustrated. The fixture  200  comprises walls  205 ,  206  and  207  and tabs  208 ,  209  and  210 . In the example shown in  FIG. 2 , tab  209  is shown as translucent so that the details of illumination module  220  can be seen, however, in practice, tab  209  typically is not translucent. The fixture also comprises rails  215  and  220  similar to the rails illustrated in  FIG. 1 . Rail  215  comprises internal channels  216  and  217  and rail  220  comprises internal channels  221  and  220 . 
     Exemplary fixture  200  also comprises illumination module  230  and illumination module  250 . Illumination module  230  comprises printed circuit board  232  on which are mounted four LEDs, two of which,  233  and  234 , are visible in  FIG. 2 . Printed circuit board  232  is mounted onto heat sink  240  which comprises fins for drawing away heat from the printed circuit board. Illumination module  230  further comprises optical element  245  seated in internal channels  216  and  221 . Illumination module  250  similarly comprises a printed circuit board mounted on a heat sink, the printed circuit board mounted with LEDs which are not visible in  FIG. 2 . Optical element  265  of illumination module  250  is also seated in internal channels  216  and  221 . Optical elements  245  and  265  shown in exemplary fixture  200  each comprise four Fresnel lens aligned with each of the four LEDs mounted on each module&#39;s printed circuit board. Fresnel lenses can be used to focus the light emitted from each LED. Although not shown in  FIG. 2 , an additional optical element, such as a diffuser, can be seated in internal channels  217  and  222  for each of the illumination modules. Diffusers can be used to soften or scatter the focused light emitted from each Fresnel lens. 
     Although not shown in  FIG. 2 , a power supply can be mounted to the heat sink  240  and supply power to illumination module  230 . A first electrical connector (not shown) can connect the power supply to the printed circuit board  232  of illumination module  230  and permit the flow of power from the power supply to the LEDs mounted on printed circuit board  232 . A second electrical connector (not shown) can connect printed circuit board  232  to the printed circuit board of illumination module  250  so that power can be fed to the printed circuit of illumination module  250 . Additional connectors can be used to connect other illumination modules so that a single power supply can provide power to an array of illumination modules. The connection of illumination modules is illustrated and described further herein in connection with  FIGS. 8-10 . 
     Referring now to  FIG. 4 , an exploded view of an exemplary light fixture  400  with an array of illumination modules is shown. As illustrated in  FIG. 4 , the array of illumination modules is expandable to provide a row that is readily length customized to meet installation or application dictates.  FIG. 4  illustrates, in exploded view, a line of nine circuit boards, one of which is labeled  410 , each circuit board having four LEDs. The heat sink  405  onto which the circuit boards are mounted can be either nine individual heat sinks or one continuous heat sink attached to all nine circuit boards. The heat sink or heat sinks can be attached to rails  415  and  420 . Exemplary embodiment  400  also illustrates nine optical elements, one of which is labeled  445 . The optical elements can fit into channels in rails  415  and  420  and are disposed over the LEDs. The exemplary embodiment shown in  FIG. 4  also illustrates a power supply  470  mounted to one side of the heat sink. As explained previously, in alternate embodiments, the power supply can be located in other positions. 
     Referring now to  FIGS. 3 and 5 , fully assembled light fixtures  300  and  500  are illustrated, each fixture comprising an array of illumination modules similar to those described in connection with the previous Figures. Fixture  300  in  FIG. 3  comprises an array of nine illumination modules similar to the previously described illumination modules. Fixture  500  of  FIG. 5  comprises an array of seven illumination modules and two spot lights  505  and  510 . As shown in  FIG. 5 , the arrays of illumination modules described herein can be interspersed with other types of lighting systems. 
     One of the advantages to using the illumination modules described in  FIGS. 1-5  is that it facilitates retrofitting existing lighting fixtures that do not use LED technology. For example, fluorescent light bulbs can be removed from the fixtures shown in  FIGS. 2-5  and replaced with the LED illumination modules described herein. As one example, the array of illumination modules can be configured for compatibility and compliance with the ceiling lighting system marketed by Armstrong World Industries under the identifier “TECHZONE.” The shape of the illumination modules described herein facilitates fitting arrays of the illumination modules into a variety of different types of light fixtures. The size and modular nature of the illumination modules also provides an efficient and cost-effective approach for retrofitting existing light fixtures. 
     Referring now to  FIGS. 6 and 7 , another exemplary embodiment is shown.  FIG. 6  shows light fixture  600  with a square array of illumination modules.  FIG. 7  provides an exploded view of fixture  600  illustrating the components of each illumination module in the square array. Similar to the illumination modules described in connection with  FIGS. 1-5 , each illumination module comprises a heat sink, a printed circuit board with one or more LEDs, and an optical element, such as one or more lenses that focus the light emitted from the LEDs. As described previously, the heat sink can be one continuous component onto which multiple printed circuit boards are mounted or, alternatively, each illumination module can have a distinct heat sink component. The square array in light fixture  600  also uses a similar system of rails to which each illumination module is attached. Light fixture  600  is different from the previously described embodiments in that it comprises multiple pairs of rails sitting side-by-side to form the square array of illumination modules. Those of skill in the art will recognize that other shapes and configurations of the illumination modules are also possible. 
     Referring now to  FIG. 8 , an exploded view of another illumination module  800  in accordance with an exemplary embodiment is illustrated.  FIG. 9  shows an assembled view of the illumination module  800  without the plate of optical material  825 . Illumination module  800  comprises a heat sink  805  to which is mounted a printed circuit board  810  comprising LED  811 . In alternate embodiments multiple LEDs can be mounted to the printed circuit board. Two hermaphroditic connectors  812  and  813  are attached to the printed circuit board  810 , one on each opposite edge of the printed circuit board  810 . In certain embodiments, as shown in  FIG. 8A , the two hermaphroditic connectors can be attached to adjacent edges of the printed circuit board  810 . In certain embodiments, three or four hermaphroditic connectors can be attached to the printed circuit board, for example one per circuit board edge. 
     A primary optic  815  also is mounted to the printed circuit board  810  to receive and process light from the LED  811 . The primary optic  815  can transfer the pattern of light emanating from the LED  811  into a desired form, for example a beam having a substantially square or rectangular format in cross section. In certain embodiments, the primary optic  815  incorporates technology as disclosed in U.S. Pat. No. 7,674,018, which is referenced above and the entire contents of which is incorporated herein by reference. Accordingly, the primary optic  815  illustrated in  FIG. 8  can comprise any of the optic embodiments and/or teaching or technologies disclosed in U.S. Pat. No. 7,674,018. Moreover, one of ordinary skill in the art having benefit of the present disclosure can apply the teachings of U.S. Pat. No. 7,674,018 so that the primary optic illustrated in  FIG. 8  produces a beam having a substantially square or rectangular form in cross section with a defined or specified intensity profile across that cross section. 
     The primary optic  815  is disposed at an entrance opening to a mock parabolic housing  820  in  FIG. 8 . In the illustrated embodiment, the mock parabolic housing  820  includes an interior having a reflective surface that receives and reflects light emitted from the primary optic  815 . In an exemplary embodiment, the cavity of the mock parabolic housing  820  has a geometric form at least part of which resembles or follows a parabola or a conic section. In certain embodiments, the mock parabolic is opaque and prevents light from transmitting between two adjacent illumination modules. In certain embodiments, the exit aperture of the mock parabolic truncates, eliminates, clips, or otherwise manipulates part of the beam of light produced by the primary optic  815 . 
     In the exemplary embodiment illustrated in  FIG. 8 , a plate of optical material  825  covers the exit aperture of the mock parabolic. In one embodiment, the plate of optical material comprises a secondary optic, such as a Fresnel lens. In another exemplary embodiment, the plate of optical material comprises a diffuser. In yet another exemplary embodiment, the plate of optical material comprises a Fresnel lens facing the primary optic  815  and diffusion features etched or otherwise formed on an outer surface of the plate. As referenced above,  FIG. 9  illustrates the components of  FIG. 8  in assembled form, but without the plate of optical material  825 . 
     Referring now to  FIG. 10 , another exemplary embodiment  1000  illustrates forming an array of the illumination modules by mating together the hermaphroditic connectors of adjacent illumination modules. In this manner, electricity can flow from a driver circuit to multiple illumination modules to power the LEDs of each illumination module. In the embodiment illustrated in  FIG. 10 , each printed circuit board has two hermaphroditic connectors, one on each opposite end enabling the illumination modules to be connected in a one-dimensional array. In alternate embodiments, connectors can be arranged along other edges of the printed circuit board so that the illumination modules can be connected in two-dimensional arrays or other arrangements. 
       FIG. 11  illustrates a simulated illumination pattern as produced by the illumination module illustrated in  FIGS. 8 and 9  and discussed above. The illumination pattern slightly overfills the target zone  1105 . Accordingly, the exit aperture of the illumination module can clip or eliminate the edges of the illumination pattern, to facilitate a fully filled aperture providing ambient light that is uniform, consistent, and aesthetically pleasing. For example, the mock parabolic housing  820  described in connection with  FIG. 8  can be used to fold the edges of the illumination pattern shown in  FIG. 11  back inward to produce the more consistent and uniform illumination pattern illustrated in  FIG. 12 .  FIG. 12  illustrates a simulated illumination pattern demonstrating consistency and uniformity as can be provided by the illumination modules described herein. 
     The embodiments described herein are illustrative and not restrictive. It should be appreciated by those skilled in the art that various modifications are well within the scope of the invention. From the foregoing, it will be appreciated that the embodiments overcome limitations in the prior art. From the description of the exemplary embodiments, equivalents of the elements shown therein will suggest themselves to those skilled in the art, and ways of constructing other embodiments will suggest themselves to practitioners of the art. Therefore, the scope of the disclosure is not limited to the examples provided herein.