There is provide a discharge lamp lighting apparatus that comprises a discharge lamp and a power supply device configured to drive a regular lighting mode and the low electric power lighting mode in a switchable manner. The power supply device configured to control a power supply to the discharge lamp such that, in the low electric power lighting mode, after a secondary protrusion forming process in which an alternating current having a frequency equal to or greater than the basic frequency in the regular lighting mode is supplied, the low electric power lighting mode transitioning to a secondary protrusion maintaining process in which a high frequency alternating current having a frequency higher than the basic frequency in the regular lighting mode, and a low frequency alternating current having a frequency lower than the frequency of the high frequency alternating current is alternately supplied.

Systems and methods for reducing contamination of one or more arc lamps are provided. One example implementation is directed to a millisecond anneal system. The millisecond anneal system includes a processing chamber for thermally treating a substrate using a millisecond anneal process. The system further includes one or more arc lamps. Each of the one or more arc lamps is coupled to a water loop for circulating water through the arc lamp during operation of the arc lamp. The system includes a reagent injection source configured to introduce a reagent, such as nitrogen gas, into water circulating through the arc lamp during operation of the arc lamp.

Electrode tips for arc lamps for use in, for instance, a millisecond anneal system are provided. In one example implementation, an electrode for an arc lamp can have an electrode tip. The surface of the electrode tip can have one or more grooves to reduce the transportation of molten material across the surface of the electrode tip. The electrode can include an interface between the electrode tip and a heat sink. The interface can have a shape designed to have a desired lateral temperature distribution across the surface of the electrode tip.

The invention describes an electrode (1) for use in a lamp (3) comprising a quartz glass envelope (30) enclosing a chamber (31), which electrode (1) comprises a tip for extending into the chamber (31) and base for embedding in a sealed portion (33) of the quartz glass envelope (30), characterized in that the base comprises a plurality of essentially smooth concave channels (2) arranged around the body of the electrode (2) and wherein the depth (d.sub.ch) of a channel (2) is preferably at most 8 percent, more preferably at most 5 percent, most preferably at most 3 percent of a diameter (D.sub.e) of the electrode (2). The invention further describes a method of manufacturing an electrode (1) for use in a lamp (3) comprising a chamber (11) in a quartz glass envelope (30), which method comprises the step of removing material from the body of the electrode (1) to form a plurality of channels (2) around the body of the electrode such that a channel (2) comprises channel side walls (62) and an essentially concave channel floor (60), and such that depth (d.sub.ch) of a channel (2) is preferably at most 8 percent, more preferably at most 5 percent, most preferably at most 3 percent of a diameter (D.sub.e) of the electrode (2). The invention also describes a lamp (3) comprising such electrodes (1), and a method of manufacturing such a lamp (3).

A discharge lamp includes an emitter other than thorium, which is added to a cathode in a luminous tube. Early depletion of the emitter due to excessive vaporization of the emitter from the cathode is prevented, while achieving stable lighting even at the start-up of the lighting. A main body part (31) of the cathode (3) is made from a high-melting-point metal material that contains no thorium, and a front end part (32) thereof is made from a high-melting-point metal material that contains an emitter (other than thorium). A sintered compact (34), which contains an emitter (other than thorium) at a concentration higher than the emitter contained in the front end part (32), is buried in a sealed space (33) that is formed within the main body part (31) and/or the front end part (32). The sintered compact (34) abuts against the front end part (32).

A DC gas discharge lamp includes an anode and a cathode having a first cathode segment, which forms the surface of the cathode at least in a region of the cathode which faces the anode and has an arc attachment region, within which an arc burning between the cathode and the anode attaches during lamp operation as intended. The first cathode segment consists of tungsten with at least one emitter material for reducing the work function of electrons from the cathode. The cathode is embodied in a manner free of thorium. The at least one emitter material has a melting point of less than 3200 K. At least one part of the surface of the cathode outside the arc attachment region is formed by a diffusion barrier for the at least one emitter material.

An electrode (1) of a discharge device (e.g. the cathode of a discharge lamp) having a side area (4) and a tip area (5) implanted with an emissive material dopant induced by ion implantation is disclosed. The side area (4) of the electrode (1) may be masked (3) during ion implantation or a diffusion barrier layer (7) may be added on the side area (4) after ion implantation.

A high-pressure discharge lamp with a burner unit which has a discharge vessel which encloses a discharge space and in which two electrodes are arranged opposite one another, wherein the electrodes each have an electrode support and an electrode tip, wherein the electrode tips are located opposite one another to form an electric arc during operation of the high-pressure discharge lamp, wherein at least a first one of the electrodes is configured as a coil electrode which has an electrode support and an electrode coil formed by a wire wound around the electrode support, wherein an exposed end of the electrode support forms the electrode tip, and wherein the electrode coil is arranged in a tip region of the electrode support adjacent to the electrode tip in the discharge space, and wherein an antenna to which voltage can be applied is routed along an outer surface of the discharge vessel. The electrode coil of the first electrode has a protrusion that protrudes beyond the outer circumference of the electrode coil toward the antenna.

The disclosure relates to a discharge lamp including a light emitting tube having a discharge space therein, and a pair of electrodes disposed in the discharge space so as to be opposed to each other, wherein a changing rate of a cross-sectional area is equal to or lower than 200%. The changing rate is a rate of change of the cross-sectional area in every 0.25 mm in a direction along an optical axis of the light emitting tube. The cross-sectional area is an area of a plane perpendicular to the optical axis in a space between an outside shape of at least one of the pair of electrodes and an inside wall of the light emitting tube.

An arc lamp includes an arc tube configured to receive a reaction gas therein, and an anode and a cathode disposed opposite one another within the arc tube and configured to generate an electrical arc. The anode includes an anode head portion extending inwardly from an end portion of the arc tube, and an anode tip portion bonded to the anode head portion and comprising a trench extending in a top surface along a peripheral region of the anode tip portion.