Abstract: According to a first embodiment, a light emitting diode (LED) light engine is described. The light emitting diode includes one or more LED devices disposed on a front side of an LED light engine substrate. A heat sink having a mating receptacle for the LED light engine is also provided. The LED light engine substrate and the mating receptacle of the heat sink define a tapered fitting by which the LED light engine is retained in the mating receptacle of the heat sink.

Abstract: Elongated lighting system comprises an elongated light pipe having first and second ends, with light supplied to those ends by at least one light source, via first and second light couplers that condition light to increase reflections within the light pipe. Light-extraction structure on the light pipe extracts light from the side of the pipe. An indentation in the light pipe has a depth and has surfaces oriented with respect to the pipe so as (1) to redirect light from the first light source that reaches the indentation after passing once through a plane adjacent the indentation, back through the plane and towards the first end; and (2) to sufficiently increase the average angular distribution of light reflected from the indentation and passing back through the plane as would cause at least 50 percent more reflections of the foregoing light within the pipe in the absence of the light-extraction structure.

Abstract: According to a first embodiment, a light emitting diode (LED) light engine is described. The light emitting diode includes one or more LED devices disposed on a front side of an LED light engine substrate. A heat sink having a mating receptacle for the LED light engine is also provided. The LED light engine substrate and the mating receptacle of the heat sink define a tapered fitting by which the LED light engine is retained in the mating receptacle of the heat sink.

Abstract: Improved side-light distribution systems are disclosed. In one embodiment, an efficient side-light distribution system includes a LED light source; a light coupler for receiving light from the LED light source at a first end and providing light at a second end to an elongated light pipe, and the elongated light pipe receives light from the LED light source at a first end and transmitting the light towards a second end. The coupler transforms at least the angular distribution of at least 70% of the light from the LED light source into an appropriate angular distribution needed for total internal reflection at a second end within the elongated light pipe. The light coupler includes a light-extraction means between the first and second ends of the light coupler for extracting light out of a side of the light coupler. At least part of the light within the light pipe is extracted out of a side of the light pipe, between the first and second ends of the light pipe, by a light-extraction means.

Abstract: Elongated lighting system comprises an elongated light pipe having first and second ends, with light supplied to those ends by at least one light source, via first and second light couplers that condition light to increase reflections within the light pipe. Light-extraction structure on the light pipe extracts light from the side of the pipe. An indentation in the light pipe has a depth and has surfaces oriented with respect to the pipe so as (1) to redirect light from the first light source that reaches the indentation after passing once through a plane adjacent the indentation, back through the plane and towards the first end; and (2) to sufficiently increase the average angular distribution of light reflected from the indentation and passing back through the plane as would cause at least 50 percent more reflections of the foregoing light within the pipe in the absence of the light-extraction structure.

Abstract: Disclosed is an LED fixture with passive cooling. The fixture includes a plurality of elongated tubes, each containing an array of LEDs mounted on a respective first surface or surfaces of one or more circuit boards. A frame mounts to a building structure and holds the ends of the tubes. Each tube is sufficiently spaced from any adjacent tube and from any other structure of the frame, and the frame is sufficiently open at the top and bottom, whereby heat from the tubes is capable of being dissipated merely by passive thermal transfer into an air flow created by the heat of the tubes, which air flow moves from beneath the tubes to above the tubes.