Abstract: A method for cleaning a translucent tube for a discharge lamp having a luminous bulb portion includes the steps of introducing a cleaning fluid from one end of the translucent tube; and allowing the cleaning fluid to flow while bringing the cleaning fluid in contact with at least an inner face of the luminous bulb portion of an inner face of the translucent tube, thereby removing impurities attached on the inner face of the luminous bulb portion.

Abstract: A method for producing a discharge lamp of the present invention includes the steps of: preparing a glass pipe for a discharge lamp having a luminous bulb portion and a side tube portion, and a single electrode assembly including an electrode structure portion that will be formed into a pair of electrodes of the discharge lamp; inserting the single electrode assembly into the glass pipe for a discharge lamp such that the electrode structure portion of the single electrode assembly is positioned in the luminous bulb portion of the glass pipe for a discharge lamp; forming a luminous bulb in which the electrode structure portion is arranged inside by attaching the side tube portion of the glass pipe for a discharge lamp to a part of the single electrode assembly; and forming a pair of electrodes in the luminous bulb by melting and cutting a part of the electrode structure portion selectively.

Abstract: A short arc mercury lamp includes a luminous bulb enclosing at least mercury as a luminous material and a pair of electrodes opposed to each other; and a pair of sealing portions for sealing a pair of metal foils electrically connected to the pair of electrodes, respectively. The electrode central axis of one of the pair of electrodes is dislocated from the electrode central axis of the other electrode. The shortest distance d (cm) between the head of one of the electrodes and the head of the other electrode is larger than the value of (6M/13.6&pgr;)⅓ when the total mass of the enclosed mercury is M (g).

Abstract: A discharge lamp includes a luminous bulb in which a luminous material is enclosed and a pair of electrodes are opposed to each other in the luminous bulb; and a pair of sealing portions for sealing a pair of metal foils electrically connected to the pair of electrodes, respectively. The pair of metal foils have a pair of external leads on the side opposite to the side electrically connected to the pair of electrodes, respectively. At least one of the pair of external leads is joined to a lead wire for external connection that is to be electrically connected to an external circuit by the plastic flow of a caulking member.

Abstract: A discharge lamp includes a luminous bulb in which a luminous material is enclosed and a pair of electrodes are opposed to each other in the luminous bulb; and a pair of sealing portions for sealing a pair of metal foils electrically connected to the pair of electrodes, respectively. Each of the pair of metal foils has an external lead on a side opposite to a side electrically connected to a corresponding electrode of the pair of electrodes. At least one of the pair of sealing portions is provided with a reflective film on a surface of the sealing portion in a portion where a connection portion of the external lead and the metal foil is sealed. The reflective film contains a material having a reflectance larger than that of a material constituting the sealing portion.