Abstract: A foil interface suited to interconnection of an electrode (18, 20) with an outer connector (24, 26) of a lamp includes a first electrically conductive connector (18, 20, 24, 26) includes a shank portion (46) and terminating in a shelf (48). A region (60) of progressively decreasing thickness is intermediate the shank portion and the shelf. An electrically conductive foil connector (28, 30) is mounted to the shelf adjacent a first end (70) of the foil connector.

Abstract: A lamp is provided having an arctube having a light-transmitting envelope. The arctube is surrounded by a gaseous medium confined by a containment envelope such as a hermetic shroud. The gaseous medium is preferably He or H2 or Ne or another gas whose thermal conductivity is greater than that of N2 at 800° C., or a mixture thereof, to help cool the arctube. The inside and/or outside of the shroud may be coated with a diffusion barrier. To help cool the hot spot of the arctube the gap between the shroud and the envelope can be made small, the portion of the shroud wall near the arc can be thickened, the arctube can be offset above the longitudinal axis of the shroud, and the return lead of the arctube can be located between the shroud and the arctube.

Abstract: A gas discharge lamp includes an arc envelope and a cooling device. Cooling passage is provided between the arc envelope and the cooling device. An airflow blocking structure is mounted rotatably to the arc envelope. The airflow blocking structure blocks airflow between the cooling device and the arc envelope except for a portion of the passage directed towards a top side of the arc envelope.