Abstract: A light fixture and method for producing downward-propagating illumination that includes an edge-lit lightguide illuminated from its perimeter. The lightguide has a light extractor, such as a dot pattern on its bottom surface, which extracts a portion of the light from inside the lightguide and directs it to a diffuser. The fixture also includes a downlight, arranged above the lightguide and producing a downlight beam downward. The downlight beam transmits from the top face through the bottom face of the lightguide and emerges from the bottom face of the lightguide as a directional beam. The downlight beam has a downlight beam footprint. The light extractor has a light extractor area that excludes the downlight beam footprint, and the diffuser has a diffuser area that also excludes the downlight beam footprint.

Abstract: A light fixture and method for producing downward-propagating illumination are disclosed. The fixture includes an edge-lit lightguide illuminated from its perimeter. The lightguide has a light extractor, such as a dot pattern on its bottom surface, which extracts a portion of the light from inside the lightguide and directs it to a diffuser. The diffuser randomizes the direction of the extracted light and forms diffuse light. The fixture also includes a downlight, arranged above the lightguide and producing a downlight beam downward. The downlight beam transmits from the top face through the bottom face of the lightguide and emerges from the bottom face of the lightguide as a directional beam. The downlight beam has a downlight beam footprint. The light extractor has a light extractor area that excludes the downlight beam footprint, and the diffuser has a diffuser area that also excludes the downlight beam footprint.

Abstract: A ceramic arc tube having an integral susceptor for RF inductive sealing is described. The integral susceptor in the form of an electrically conductive coating is applied directly to the surface of the arc tube in the seal region. This enables RF heating which is sufficient to melt a frit material and hermetically seal the arc tube. The integral susceptor further provides for a more controlled placement of the seal.

Abstract: A method of removing contaminants from a double-ended arc discharge tube includes the steps of providing at least one capillary channel at each end of the tube, where the ends of the tube are sealed closed except at the capillary channels, and introducing a flushing gas into the tube through one capillary channel at one end of the tube and removing the flushing gas and contaminants through another capillary channel at another end of the tube. During manufacture, the double-ended arc discharge tube has a sealed electrode and an open capillary channel at each end of the tube.

Abstract: A method of removing contaminants from a double-ended arc discharge tube includes the steps of providing at least one capillary channel at each end of the tube, where the ends of the tube are sealed closed except at the capillary channels, and introducing a flushing gas into the tube through one capillary channel at one end of the tube and removing the flushing gas and contaminants through another capillary channel at another end of the tube. During manufacture, the double-ended arc discharge tube has a sealed electrode and an open capillary channel at each end of the tube.

Abstract: A high pressure, lamp may be made in a pressure vessel by using an induction coil to melt an edge portion of a sealing wafer pressed against the circumference of an opening in the body of the lamp envelope. The pressure vessel and the lamp envelope are filled with desired fill materials. Induction heating is carried out by the induction coil and induction receiver that presses against the wafer, the lamp envelope or both to hold the melting piece or pieces in contact. The induction receiver may be fused to the lamp body forming a functional part of the overall lamp structure. The preferred resulting lamp includes a bonded metal piece that can be conveniently used for electrical or mechanical coupling or positioning of the lamp with respect to a base.

Abstract: A high pressure, lamp may be made in a pressure vessel by using an induction coil to melt an edge portion of a sealing wafer pressed against the circumference of an opening in the body of the lamp envelope. The pressure vessel and the lamp envelope are filled with desired fill materials. Induction heating is carried out by the induction coil and induction receiver that presses against the wafer, the lamp envelope or both to hold the melting piece or pieces in contact. The induction receiver may be fused to the lamp body forming a functional part of the overall lamp structure. The preferred resulting lamp includes a bonded metal piece that can be conveniently used for electrical or mechanical coupling or positioning of the lamp with respect to a base.

Abstract: An electrode feedthrough assembly for a ceramic arc tube of the type used in high pressure sodium arc lamps. The electrode feedthrough assembly is particularly useful in an external reservoir arc tube wherein an interior region of a feedthrough tube is utilized as a reservoir for the lamp fill material. The electrode feedthrough assembly includes a feedthrough tube, an electrode assembly attached to the feedthrough tube and a connection wire. The feedthrough tube has a closed end external to the arc tube. The feedthrough tube and the closed end thereof are formed in a single process, preferably by deep drawing, without welding, crimping or fusing. Passages to the interior of the feedthrough tube are provided by crimping the electrode support rod to the feedthrough tube with a six jaw crimping arrangement wherein two of the crimping jaws are shorter than the other four. The connection wire is attached to the feedthrough tube and includes a portion on the axis of the tube.