Abstract: The invention relates to a vehicle headlight bulb comprising a bulb socket, an illuminant (2) arranged inside the bulb socket (1), and a base comprising a metallic sleeve (3) in which a sealed end (11) of the socket (1) is fixed. According to the invention, at least one of the narrow front sides (111) of the sealed end (11) of the socket (1) is provided with a serrated profiled element (1110) which extends in the longitudinal direction of the bulb and forms a latch connection with at least one locking plate (33) formed on the base sleeve (3).

Abstract: The incandescent lamp, which uses a carbon cycle process, is equipped with a luminous body which, together with a fill, is introduced in a vacuum-tight manner into a bulb, the luminous body including a metal carbide, the melting point of which is above that of tungsten. The distance between the luminous body and the wall of the bulb is less than 18 mm, with a first cycle process, which is attributed to the carbon, being effected by the use of carbon and hydrogen as fill additive, and a second cycle process, which is attributed to the metal, being effected by the use of halogen.

Abstract: To accurately position a halogen cycle incandescent lamp within a reflector o form a sealed-beam headlight, a carrier is provided for the lamp with a seating surface thereon, the lamp being accurately positioned and aligned with respect to the carrier and its seating surface by optical alignment outside of the reflector, the seating surface then being fitted against a matching abutment forming a locating surface on the reflector, the lamp-carrier subassembly being secured in the reflector, for example by form-fitting interengagement, adhesion, or the like. The reflector may have a large opening and the carrier in form of a disk, or smaller openings and the carrier in form of a ring inserted from the reflector end into the reflector.