Abstract:
A ceiling tile system comprises modular acoustic light-emitting modules which can be of a standard size to be fitted into a hung ceiling or other ceiling system in conjunction with similar acoustic light-emitting modules or conventional ceiling tiles. Each acoustic light-emitting module includes a backing panel, a cover, and a rigid spacing member extending between the backing panel and the cover, with solid state light-emitting elements such as light-emitting diodes (LEDs) arrayed within each module. The cover may be made of fabric including metallic threads to enhance the diffusion of light. In one embodiment, two arrays of LEDs are provided on respective modules. The arrays may be driven independently or together. The LEDs provide shades of white light or colored light, as desired. The cover and lighting elements may be readily removable from the backing panel for ease of maintenance.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims priority under 35 U.S.C. §119(e) of U.S. Provisional Patent Application No. 60/401,356 filed Aug. 6, 2002, the disclosure of which is hereby incorporated by reference herein. 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable 
    
    
     BACKGROUND OF THE INVENTION 
     The invention relates to the field of acoustic tile systems and integral lighting elements. 
     Acoustic improvements are needed in most office, commercial and institutional environments. Sound absorbing sheet products, wall coverings or acoustic tiles are specified and applied in almost every contemporary building to address this need. Such existing systems accommodate all building life safety codes, are easy to install, inexpensive and ubiquitous. However, existing acoustic tiles have performance limitations in the face of changing work and lifestyle practices. The miniaturization of mobile communication and information tools and the advent of internet and wireless distribution networks have placed a premium on spatial flexibility for individuals and small and large groups. As mobility increases in residential, public and commercial settings, the overall architectural flexibility of space is increasingly important, and the attendant problem of providing acoustic privacy and a sense of individual place also increases. 
     Currently, acoustic controls are provided for example in the form of suspended ceiling tiles, which are combined with separate lay-in fluorescent light fixtures for lighting needs. However, this standard arrangement may be less than desirable from the perspectives of functional energy consumption, light control, light personalization and aesthetic appearance. The ceiling is an important architectural surface, yet its functional potential to both absorb sound and to distribute light in an energy-efficient manner which allows for the control of individual ceiling areas with an aesthetic design is currently ignored. 
     Thus, there is a need for an improved acoustic tile system that can be easily adapted for example to existing ceiling systems as well as building codes and construction conventions. It is advantageous for such an improved ceiling system to incorporate lighting and acoustic needs while providing for flexible aesthetic and functional alternatives to standard acoustic tile systems. 
     BRIEF SUMMARY OF THE INVENTION 
     In accordance with the present invention, an acoustic light emitting tile system is disclosed which provides improvements in both lighting and acoustical performance with greater aesthetic appeal than traditional systems. 
     The tile system comprises modules which can be incorporated into a conventional, modular hung ceiling or similar ceiling system. The tile system can be readily implemented within existing construction practices and can meet construction and architectural standards and building codes, including such codes for fire-rated assemblies where the wall cladding and structural connections contribute to the fire-rated structure of the building. The system also accommodates interruptions in the ceiling such as the penetration of sprinkler heads, structural elements, and other penetrations, and provides access to the plenum for maintenance. 
     Each module includes a backing panel, a light-diffusing, acoustically non-reflective cover, and light-emitting elements disposed between the backing panel and cover. The backing panel can be curved or planar in form, and may be a sound absorbing ceiling tile or an acoustic backing panel. The cover may be a woven fabric, a non-woven material, or a translucent rigid material which is micro-perforated or similarly treated to provide for sound absorption. A cylindrical sleeve or similar rigid spacing member may be used to separate the cover from the backing panel, creating an aesthetically interesting shape with the functional ability to scatter sound by creating non parallel relationships between floor and ceiling. These relationships may be customized in the manufacturing process by varying the dimension between the backing panel and the rigid spacer member, creating different sculptural and sound scattering topographies in the ceiling plane. A void between the backing panel and the rigid spacer member may be filled with lightweight sound absorbent foam, pellets or other acoustic materials. 
     The modules may be used with other like modules for an independent ambient lighting system in which solid state lighting elements such as light-emitting diodes (LEDs), high brightness LEDs (HBLEDs), organic LEDs (OLEDs), or electroluminescent (EL) elements replace conventional fluorescent lighting. Alternatively, the modules may be used in conjunction with traditional and/or compact fluorescent light sources. The modules can be adjacent to form a continuous ceiling surface, or they may be spaced apart and intermixed with other ceiling components such as traditional acoustic ceiling tiles and other existing standard light fixtures. Additionally, the modules can be used on vertical wall surfaces or other surfaces where both lighting and acoustic functionality is desired. 
     The solid state lighting elements can be arrayed in one or more assemblies within each module, such as along the backing panel or the spacer member or integrated into the cover. In one embodiment, two arrays of LEDs are provided on respective modules. The arrays may be driven independently or together. The LEDs provide shades of white light or colored light, as desired. 
     The system can provide a dynamic sculptural ceiling surface that integrates acoustic treatment with energy-efficient, analog and digitally controllable, ambient lighting employing color-changing solid state lighting elements. The integration of acoustics and lighting permits a more aesthetically pleasing, consistent and highly adaptable ceiling surface which is uninterrupted by the configuration and glare of individual lighting fixtures. 
     In particular, the solid-state lighting elements can be hardwired and controlled with conventional switches, or they can be controlled with digital electronics using either hardwired or wireless methods. Digital electronic controls used in conjunction with the system result in greater individual control of single modules or of an area of modules in an energy efficient manner. Individuals or groups can select the intensity and/or color of light for a particular ceiling area according to need and preference. This control can happen in real time or it can be set to automatically change over a period of time, in conjunction with a microprocessor or other electronic control device. 
     Additionally, the disclosed system provides the ability to “undress” or strip back an outer part of a ceiling covering surface for maintenance rather than requiring the displacing or replacing of a complete rigid tile as is the current convention. This feature has the benefit of enabling maintenance and access to the lighting elements without interfering with the fire-rated wall or ceiling panel assembly. 
     Other aspects, features, and advantages of the present invention will be apparent from the Detailed Description of the Invention that follows. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
       The invention will be more fully understood by reference to the following Detailed Description of the Invention in conjunction with the Drawing, of which: 
         FIG. 1  is a perspective view of a light-emitting acoustic module in accordance with the present invention; 
         FIG. 2  is a section view of the light-emitting acoustic module of  FIG. 1 ; 
         FIG. 3  is a diagram of a ceiling surface including numerous adjacent modules of the type shown in  FIG. 1 ; 
         FIG. 4  is a diagram of a ceiling surface including spaced-apart modules of the type shown in  FIG. 1 ; 
         FIG. 5  is a diagram of a ceiling surface including modules of the type shown in  FIG. 1  in conjunction with standard fluorescent light fixtures; 
         FIG. 6  is a diagram of a ceiling surface including modules similar to the module of  FIG. 1  in conjunction with fire system sprinkler heads; 
         FIG. 7  is a section view of a module for use with sprinkler heads as in  FIG. 6 ; 
         FIGS. 8-10  are section views of modules similar to the module of  FIG. 1  with alternative features; and 
         FIGS. 11-16  are diagrams of LED assemblies that can be used in a light-emitting acoustic module in accordance with the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  shows a perspective view of a light-emitting acoustic module  10 . The module  10  includes a backing panel  12  with a light-diffusing cover  14  extending across one surface. The cover  14  covers a cylindrical sleeve  16  extending from one surface of the backing panel  12  to provide the module  10  with a truncated conical shape. In one embodiment, the cover  14  is made of a woven cloth such as polyester with metallic light reflective fibers. The woven cloth may be stretchable and installed in a stretched condition, or it may be draped. Other embodiments may deploy translucent or honeycomb structured materials or non woven materials, or rigid coverings with micro-perforations to permit sound entry. Such rigid coverings may be enhanced by the integration of luminous phosphor pigments. When excited by the LEDs or fluorescent sources, such a cover gives off light to provide a practical safety function in the event of a power loss. 
     The cover  14  is attached to the backing panel in one of two manners. A stretchable elastic sleeve (not shown) may be placed along the edges of the cover  14  and slipped over the backing panel  12 , additionally securing the cylindrical sleeve  16  and internal lighting elements (not shown in  FIG. 1 ). When the module  10  is displaced for installation or to permit access to the plenum, its edges are exposed and the elastic sleeve may be readily removed, providing access to the lighting elements. Alternatively, in the case where direct access is desirable from below (without engagement of the plenum) a hook-and-pile, snap, or other mechanical fastener may be used to allow the cover  14  to be readily removed without displacing the backing panel  12 . 
     Referring to  FIG. 2 , the module  10  is shown in schematic edge view as part of a hung ceiling of like modules. The edges of the backing panel  12  are formed to provide for overlap between adjacent modules. Also, a narrow slot  15  is formed at the edges to receive one flange of a T-shaped hanger  17 . The other flange of the hanger  17  supports the extending edge portion  19  of an adjacent module. Although in the illustrated embodiment the T-shaped hanger  17  is of the type found in conventional hung ceiling systems, other types of support elements may be employed in alternative embodiments. In an application in which the module  10  is attached to a wall (in a movie theater for example), separate mechanical fasteners may be used to attach the modules  10  to a system of T-shaped support elements. 
     The sleeve  16  is made of clear acrylic, perforated metal or other rigid material and is disposed in a slight depression in the backing panel  12 . The sleeve  16  is attached to the backing panel  12  with a flexible pop-in lip, screw-in sleeve connection or other mechanical fastener. A translucent diffuser film  22  is disposed over the outer end of the sleeve  16  and supported by the cover  14 . The diffuser film  22  may be a lenticular surface used to help spread and direct the light, such as a lenticular pattern etched on a polycarbonate disk. 
     An LED assembly  18  includes a ring of LEDs contained on a rigid circuit board which is disposed on the backing panel  12 ), which may be a sound-absorbing standard ceiling module panel concealed by the cover  14  or an acoustic backing board. A second LED assembly  20  includes a flexible strip of LEDs disposed around the outer perimeter of the sleeve  16 . Examples of components that can be used in LED assemblies  18  and  20  are described below. The LED assemblies  18  and  20  receive electrical power via wires  21  extending though an opening in the backing panel  12 . Other embodiments may employ remote photo-voltaic power sources or battery packs, which are efficient for solid state light sources such as LEDs. Various other configurations of LEDs can be provided to achieve particular lighting, signaling and wayfinding effects. 
     LED-based lighting elements such as LED assemblies  18  and  20  (and including variants such as OLEDs and HBLEDs) provide a number of benefits in comparison to conventional fluorescent or other lighting fixtures. They require lower operating voltages. The LEDs are long lasting and can typically be employed for a period of 10 years at full intensity. The LEDs are also efficient and can provide significant energy savings. In addition, the LEDs can easily be electronically controlled with wireless or hardwired circuits, and can be linked to computerized facility management systems, timers, motion/photo sensors, microprocessors and the like. Moreover, the LEDs can be programmed to provide light in various tile sequence color mixes or levels of intensity. 
     Under daylight conditions, the cover  14  is effective to distribute daylight deeper into the ceiling space from perimeter windows or other sources of daylight. The cover  14  also diffuses the LED light to produce an even wash of light across the surface of the backing panel  12 . Sound is absorbed through the cover  14  and by the backing panel  12 . The interior air cavity or space between the backing panel  12  and the cover  14  also attenuates and traps sound. Speakers and other audio system components may be integrated into the air cavity where they are concealed by the cover  14 . The conical form of the cover  14  also serves to diffuse sound and to alter the typical parallel spacing between floor and ceiling. 
       FIG. 3  shows a ceiling surface including a number of modules  10  arranged adjacent to each other.  FIG. 4  shows an alternative ceiling surface in which the modules  10  are spaced apart, for example by conventional acoustic ceiling tiles  24 . In each case, the modules  10  are shown in a state in which only the inner LED assembly  18  is lighted. As can be appreciated, the conical form of the module  10  with its light diffusing cover  14  and integral solid state light assemblies  18  and  20  produces a ceiling plane with unique functional and aesthetic effects. The degree of blended light and color from the two LED assemblies  18  and  20  creates different perceptions of the physical shape of the modules  10 . The ceiling plane can appear to be rounded, flattened and variously modulated by the play of receding color light within the volume of each module  10 . Unlike conventional hung ceilings, the modules  10  create ceiling lighting which can be adjusted by users to create variable and dynamic luminous and sculptural effects. 
       FIG. 5  shows a ceiling surface in which the modules  10  are interspersed with standard fluorescent lighting fixtures  26 . 
       FIGS. 6 and 7  illustrate the use of the modules in conjunction with fire system sprinkler heads. A sprinkler head with a conventional fusible link and cover plate  28  may be located flush to the backing panel  12  within the sleeve  16  in place of the LED assembly  18 . In this embodiment, the diffuser  22  is also absent, and the cover  14  is secured around the opening established by LED assembly  20  using a rigid edge lip of acrylic or metal. An opening is also formed in the backing panel  12  to permit passage of the pipe  30 . Alternatively (not shown in  FIG. 7 ), the sprinkler head may be extended through the void within the sleeve  16  to protrude beyond the end of the sleeve  16 . 
       FIG. 8  shows a module including speakers  32  and  34 . The speaker  32  is disposed within the sleeve  16 , while the speakers  34  are disposed in the cavity lying between the cover  14  and the backing panel  12  outside the sleeve  16 . Alternative embodiments may employ only the central speaker  32  or only the outer speaker(s)  34 . 
       FIG. 9  shows a module including a wireless/infrared (IR) router or network access point  36 .  FIG. 10  shows a module incorporating a circular fluorescent lamp  38 . 
       FIGS. 11-16  show various configurations of LED assemblies that may be employed.  FIG. 11  shows an assembly  40  employing a circular PC board  42  with LEDs  44  arranged along the inner edge. The assembly  40  can serve as the inner LED assembly  18  of the module  10  (see  FIG. 2 ).  FIG. 12  shows a rectangular assembly  46 .  FIG. 13  shows a grid formed on a flexible circuit  48 . Such flexible circuits can be employed in a variety of ways. In the module  10  described above, for example, one or more circuits  48  can be wrapped around the outer part of the sleeve  16 .  FIG. 14  shows an assembly in which blocks  50  each having a 2×2 array of LEDs are interconnected by wire in a chain-like fashion.  FIG. 15  shows a strip  52  and  FIG. 16  shows a strip  54  of LEDs on a narrow flexible circuit board. The strip  54  can serve as the outer LED assembly  20  of the module  10  (see  FIG. 2 ). 
     The modules  10  can be manufactured as integrated units containing the LED assemblies  18  and  20  along with the cover  14  and other components, providing for ready installation and replaceability. Alternatively, the LED assemblies  18  and  20  can be provided as separate elements which are installed on site on the modules  10 . 
     Although in the illustrated embodiment, the backing panel  12  is planar, it may be advantageous to employ other shapes in alternative embodiments, including for example a curved shape like the shape of a shallow bowl. Additionally, the modules may be employed either singly or in clusters as opposed to an array as illustrated in  FIGS. 3-5  for example. Such configurations would generally employ different support structures than the grid of T-shaped hangers  17  employed in a typical hung ceiling system. For example, a module may be attached to support elements via mounting features on the back of the module. In alternative arrangements employing clusters of modules, modules may be disposed at different heights and at different angles to permit acoustic tuning for example. Rather than being placed edge-to-edge, it may be desirable that the modules overlap in such embodiments. Additionally, it may be desirable to employ non-rectangular backing panels, such as round or oval. 
     It will be apparent to those skilled in the art that modifications to and variations of the disclosed methods and apparatus are possible without departing from the inventive concepts disclosed herein, and therefore the invention should not be viewed as limited except to the full scope and spirit of the appended claims.