Abstract: The invention relates to a high-pressure discharge lamp provided with a discharge vessel with a ceramic wall which has an outer surface on which a metallic coating is present. According to the invention, the coating is a metal layer sintered on the ceramic wall, which sintering process takes place during sintering of the discharge vessel so as to achieve translucence.

Abstract: A high-pressure discharge lamp of the invention includes a ceramic discharge vessel (10) in which a first and a second electrode (40a, 40b) are arranged and which encloses a discharge space (11 ) which is provided with a filling containing a metal halide. The discharge vessel (10) has a central zone (20) between the electrodes (40a, 40b) and a first and a second cylindrical end zone (30a, 30b) which each surround a current supply conductor (50a, 50b) connected to a respective electrode (40a, 40b). At least the first end zone (30a) has a diameter smaller than the smallest diameter of the central zone (20). The current supply conductor (50a) through the first end zone (30a) has a halide resistant portion (51a) which faces the discharge space (11) and a portion (52a) permeable to hydrogen and oxygen and facing away from the discharge space (11).

Abstract: The high pressure discharge lamp has an elongate discharge vessel of ceramic material. The outside surface area of the wall of the discharge vessel is strongly increased by a relief. Since a higher heat flow from the discharge vessel to the environment is possible, the lamp can withstand a higher load. In this way, lamp properties such as luminous flux, color rendering index and/or color temperature can be improved.

Abstract: The invention relates to a high-pressure discharge lamp comprising a discharge vessel (3) enclosing a discharge space (3b) and provided with two main electrodes (4,5). Each of the main electrodes is connected to a lead-through member (40,50), which is enclosed with a clearance space (10) by a closing part (30) and is connected thereto by means of a melting glass connection (9) in a gas-tight manner. According to the invention, the lead-through member is provided with a proturberance (51) reaching as far as the closing part in such a manner that the lead-through member (50) is passed with a clamping fit through the ceramic closure member. Thus, the lead-through member is fixed, as a result of which the manufacture of the lamp is considerably simplified.

Abstract: A low-pressure mercury vapor discharge lamp having a lamp envelope (1) which encloses a folded tubular discharge vessel (2), the discharge vessel being provided with an appendix (6) which is kept at a relatively low temperature by a heat shield (7) located within the lamp envelope. The heat shield shields the outer wall surface of the appendix from the outer wall of the discharge vessel. The cooler appendix serves to maintain the mercury vapor pressure at an optimum value during operation of the lamp.