Abstract: The low pressure sodium discharge lamp has a discharge vessel (1) having pinch seals (2) through which current conductors (4) extend towards electrodes (3) inside the discharge vessel (1). The current conductors (4) each have a first glass coating (5), which extends from inside a pinch seal (2) into the discharge vessel (1) and a second lime glass coating (6) abutting the first (5) and extending to outside the discharge vessel (1). A new first sodium resistant glass coating (5), which is substantially devoid of borate, is defined.

Abstract: In the low-pressure sodium discharge lamp the current conductors (3) have a first (4) and a second glass coating (6). The first coating (5) of borate glass extends from inside the discharge vessel (1) through a pinch seal (4). The second coating (6) of lime glass envelopes the first one (5) within the pinch seal (4) and extends to outside the discharge vessel (4). The occurrence of cracks in the pinch seal is thereby obviated.

Abstract: A high pressure discharge lamp includes a sealed lamp vessel (1) having a quartz glass wall (2) enclosing a discharge space (3). Metal foils (4) are embedded in the wall, connected to electrode rods (6), and have a circumferential coating (7) of quartz glass at least adjacent the metal foil. The coating has a firm adherence to the rod. It may comprise in its boundary (7') adjoining the rod/coating interface an addition, e.g. selected from a group comprising thorium, yttrium, hafnium. Alternatively, rhenium may be present at the surface of the rod, giving an interlocking configuration of the rod and its coating. Due to a strong adherence of the quartz glass to the rod upon completing a seal, and due to large differences in expansion coefficients, the coating is torn off from the wall so as to be mechanically loose from the wall. The coating prevents premature failure of the lamp caused by leakage.