Abstract: A high intensity discharge lamp, the lamp including a light emitting vessel having a wall made of ceramic material that defines an inner space with a first end portion having a respective first opening formed therein and a second end portion having a respective second opening formed therein, two discharge electrodes, with a first electrode extending therethrough the first opening of the first end portion of the vessel and a second electrode extending therethrough the second opening of the second end portion of the vessel, together forming a gap between ends of the discharge electrodes positioned within the vessel, wherein the light emitting vessel defines an inner space characterized by an inner diameter ranging from and including 1 millimeters to 3 millimeters and an inner length between and including 5 millimeters to 10 millimeters, wherein the wall of the vessel has a thickness ranging between and including 0.3 millimeters to 0.

Abstract: A transparent sintered yttrium aluminum garnet ceramic material formed from a solid-state reaction of a mixture of yttrium oxide powder and aluminum oxide powder during sintering. The ceramic material preferably has an in-line transmission of greater than 75% so it may used to fabricate arc tubes for high intensity discharge lamps used in automotive headlamps.

Abstract: A high intensity discharge lamp, the lamp including a light emitting vessel having a wall made of ceramic material that defines an inner space with a first end portion having a respective first opening formed therein and a second end portion having a respective second opening formed therein, two discharge electrodes, with a first electrode extending therethrough the first opening of the first end portion of the vessel and a second electrode extending therethrough the second opening of the second end portion of the vessel, together forming a gap between ends of the discharge electrodes positioned within the vessel, wherein the light emitting vessel defines an inner space characterized by an inner diameter ranging from and including 1 millimeters to 3 millimeters and an inner length between and including 5 millimeters to 10 millimeters, wherein the wall of the vessel has a thickness ranging between and including 0.3 millimeters to 0.

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.

Abstract: A method of repairing a crack in at least one side of a dovetail portion of a generator rotor coil slot wall, the dovetail portion having received at least two axially adjacent steel wedges and including at least a radial entry surface, an inwardly tapered surface and an intermediate radial surface, the method comprising a) machining a groove at least partly along the inwardly tapered surface to remove damaged material from the coil slot wall; and b) replacing the at least two axially adjacent steel wedges.