Abstract: A socketed high pressure gas discharge lamp having a lamp vessel comprising a space sealed by at least one seal. The discharge lamp further comprising a socket in which the lamp vessel is mounted with its seal and fixed with cement. A lamp axis extending through the socket and through the space of the lamp vessel. The socket is provided with at least one opening extending axially through the socket from its base side to its front side. The opening has an annular wall which is either formed only by the socket or by a combination of both the socket and the seal of the lamp vessel. Preferably, the opening is located on either side of the seal.

Abstract: A socketed high pressure gas discharge lamp having a lamp vessel comprising a space sealed by at least one seal. The discharge lamp further comprising a socket in which the lamp vessel is mounted with its seal and fixed with cement. A lamp axis extending through the socket and through the space of the lamp vessel. The socket is provided with at least one opening extending axially through the socket from its base side to its front side. The opening has an annular wall which is either formed only by the socket or by a combination of both the socket and the seal of the lamp vessel. Preferably, the opening is located on either side of the seal.

Abstract: The invention relates to a high intensity discharge lamp provided with a discharge vessel enclosing a discharge space comprising an ionizable filling including besides mercury a rare earth halide, which lamp emits during stable operation light with a color temperature Tc of at least 7000K. According to the invention the lamp of the type described in the opening paragraph is therefore characterized in that the rare earth of the rare earth halide comprises Tb or Tb and Dy.