The present invention relates to lighting systems and, in particular, to lighting systems employing constructive occlusion.
Constructive occlusion techniques have been developed to provide tailored light intensity distributions from luminaires, including low intensity illumination in regions not covered by direct illumination. Current luminaire systems utilize a mask and cavity structure to achieve constructive occlusion. Radiant energy from one or more light sources, for example, reflects and diffuses within the volume between the mask and the cavity. The mask constructively occludes the aperture of the cavity, and the reflected light emerging from between the mask and the cavity provides a desired illumination.
However, using a mask to occlude the aperture of the cavity results in losses in lighting efficiency from the luminaire.
In view of the efficiency disadvantages of current constructive occlusion luminaires, the present invention, in some embodiments, provides luminaires having constructive occlusion light distributions while demonstrating increased lighting efficiencies.
In some embodiments, a luminaire described herein comprises at least one light source, at least one reflector cavity and an optical element positioned to receive light reflected from the at least one reflector cavity, wherein the luminaire does not comprise a mask at least partially occluding the aperture of the at least one reflector cavity. In some embodiments, the at least one reflector cavity is semi toroidal. Moreover, in some embodiments, the optical element comprises a reflective optical element, a refractive optical element or a combination thereof.
In another aspect, the present invention provides methods of lighting a surface. In some embodiments, a method of lighting a surface comprises providing a luminaire comprising at least one light source, at least one reflector cavity and an optical element positioned to receive light reflected from the at least one reflector cavity, wherein the luminaire does not comprise a mask at least partially occluding the aperture of the at least one reflector cavity, reflecting light from the light source off the at least one reflector cavity to the optical element and reflecting or refracting the light received from the at least one reflector cavity out of the luminaire with the optical element.
These and other embodiments are discussed in greater detail in the detailed description which follows.
The present invention can be understood more readily by reference to the following detailed description and drawings and their previous and following descriptions. Elements, apparatus and methods of the present invention, however, are not limited to the specific embodiments presented in the detailed description and drawings. It should be recognized that these embodiments are merely illustrative of the principles of the present invention. Numerous modifications and adaptations will be readily apparent to those of skill in the art without departing from the spirit and scope of the invention.
As described herein, the present invention, in some embodiments, provides luminaires having constructive occlusion light distributions without employing the traditional architectures used to achieve such distributions. As a result, luminaires described herein can demonstrate enhanced lighting efficiencies in comparison to prior luminaires utilizing constructive occlusion architectures.
In some embodiments a luminaire described herein comprises at least one light source, at least one reflector cavity and an optical element positioned to receive light reflected from the at least one reflector cavity, wherein the luminaire does not comprise a mask at least partially occluding the aperture of the at least one reflector cavity. Because the luminaire does not include a mask, the light can exit the luminaire unimpeded—in other words, light exiting the luminaire is not blocked (or masked) by any structure located within the opening of the luminaire.
With reference to
With reference to
In some embodiments, an optical element 130 is removably coupled to the surface 140 of the at least one reflector cavity 110, thereby permitting interchangeability with other optical elements to create different light distributions, surface effects and/or color. The size and shape of the optical element 130, in some embodiments, can vary to create different sized distributions and output larger or smaller candle power distributions. The optical element 130, in some embodiments, can protrude outside the reflector cavity 110 to widen the light distribution above 180 degrees.
As described herein, an optical element 130 is operable to receive light reflected from the at least one reflector cavity 110 and reflect and/or refract the received light out of the luminaire 200. In reflecting and/or refracting light received from one or more reflector cavities 110, the optical element 130 can tailor the light distribution of the luminaire 200. Moreover, as the optical element 130 does not block light as a mask does in prior luminaires that utilize constructive occlusion, the optical element 130 increases lighting efficiencies. In some embodiments, luminaires described herein have an efficiency of at least 60% or at least 65%. In some embodiments, luminaires have an efficiency of at least 70% or at least 80%.
An optical element 130 can have any desired shape not inconsistent with the objectives of the present invention.
More specifically, at least a portion (or the entirety) of the optical element 130 and/or surface 140 of reflector cavity 110 may have extremely high surface reflectivity, preferably, but not necessarily, between 96%-99.5%, inclusive and more preferably 98.5-99%. To achieve the desired reflectivity, in one embodiment the optical element 130 and/or surface 140 of reflector cavity 110 is coated with a diffuse, reflective material, including, but not limited to, reflective paints. Alternatively, the optical element 130 and/or surface 140 of reflector cavity 110 could include a layer of a reflective flexible sheet of material such as one or more of the materials sold under the tradenames GL-22, GL-80, GL-30 or Optilon™, all available from DuPont. Alternative materials include Miro® reflective aluminum materials, available from Alanod, and micro cellular polyethylene (“MCPET”), available from Furukawa. Specular materials would also be suitable. The reflective material may be substantially glossy or substantially flat. In one example, the reflective material is preferably matte white to diffusely reflect incident light. Other embodiments may utilize textured or colored paints or impart a baffled shape to the interior optical element 130 and/or surface 140 of reflector cavity 110 to obtain a desired reflection. Alternatively, the optical element 130 and/or surface 140 of reflector cavity 110 can be formed from a reflective material so that the surface of the optical element 130 and/or surface 140 of reflector cavity 110 need not be separately treated to attain the desired reflectivity.
It will be recognized that some light may, but need not necessarily, reflect directly off the surface 140 of reflector cavity 110 and exit the luminaire 200 without first reflecting off the optical element 130.
In some embodiments, a light source for a luminaire described herein comprises one or more LEDs 150. In some embodiments, a plurality of LEDs 150 are arranged on a printed circuit board 170 (see
In one embodiment a heat sink 160 (see
In some embodiments, a luminaire 200 described herein further comprises an occlusion shield 180. An occlusion shield 180, in some embodiments, can widen or narrow the distribution of light out of the luminaire 200. As the occlusion shield 180 is cylindrical and hollow. In some embodiments, the occlusion shield 180 does not function as a mask in traditional constructively occluded architectures.
With reference to
In another aspect, the present invention provides methods of lighting a surface. In some embodiments, a method of lighting a surface comprises providing a luminaire 200 comprising at least one light source, at least one reflector 100 having a reflector cavity 110 and an optical element 130 positioned to receive light reflected from the at least one reflector cavity 110, wherein the luminaire 200 does not comprise a mask at least partially occluding the aperture of the at least one reflector cavity 110, reflecting light from the light source off the at least one reflector cavity 110 to the optical element 130 and reflecting or refracting the light received from the at least one reflector cavity 110 out of the luminaire.
Various embodiments of the invention have been described in fulfillment of the various objectives of the invention. It should be recognized that these embodiments are merely illustrative of the principles of the present invention. Numerous modifications and adaptations thereof will be readily apparent to those skilled in the art without departing from the spirit and scope of the invention.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/US11/24922 | 2/15/2011 | WO | 00 | 8/15/2012 |
Number | Date | Country | |
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61304761 | Feb 2010 | US |