Abstract: To retain a discharge vessel 1, a groove 12 is formed in a re-entrant portion 3 of the vessel. The grooves 12 engages a corresponding notch 13 in a coil former of a coil assembly 6, housed in the re-entrant. The coil former is sufficiently resilient to be deflected by the groove as the vessel 1 is pushed onto the former. The arrangement may have means to prevent the vessel rotating about the coil assembly.

Abstract: An electrodeless, low pressure gas discharge lamp includes a vitreous envelope containing a discharge medium and being shaped with an external chamber for receiving an electrical excitation circuit. The excitation circuit is effective for exciting the discharge medium to emit light with electromagnetic fields that are generated by the excitation circuit. A circuit is included for supplying electrical power from power mains to the excitation circuit. A transparent, electrically conductive coating is provided atop the vitreous envelope and is electrically connected substantially directly to one of the power mains at any given time. A transparent, electrically insulative coating is disposed atop the electrically conductive coating, and comprises a contiguous, inorganic glass layer. The insulative coating preferably has a minimum coating thickness of at least about 3.1 microns.