Patent ID: 6137225
Filing Date: 2000-10-24
Classification: H01J,Y02B

Abstract:
A low-pressure discharge lamp provided with a discharge vessel (5) which is closed in a gastight manner and which contains an ionizable filling, and further provided with electrodes (6a, 6b) for maintaining an electric discharge in the discharge vessel (5), at least one of the electrodes (6a) being positioned inside the discharge vessel (5), which electrode (6a) comprises a coil (60a) of a refractory metal which is electrically connected to current conductors (7a, 7a') which extend to outside the discharge vessel (5), which coil (60a) has a central portion (61a) which is coated with an electron-emitting material and has end portions (62a, 62a') on either side between the central portion (61a) and respective current conductors (7a, 7a'), which end portions (62a, 62a') are coated with a protective material consisting essentially of at least one oxide of at least one of calcium and magnesium.