||Japan Storage Battery Company, trading under its brand name GS, has a very small business unit which is engaged solely with the development and manufacture of high wattage ceramic discharge lamps.
Their products were first shown during 2000, comprising a 220W and 360W lamp with integrated glowbottle starter, for use as an energy saving retrofit for high pressure mercury lamps. The lamp here is a 230W version without starter, intended for use with an external ignitor on mercury gear.
The raw alumina arc tube in this lamp originates from NGK's Japanese operation. It has been dosed and sealed however in the piloting production labs of GS. A molybdenum starting wire runs parallel to its axis, connected to the frame via a bi-metal switch to electrically isolate it once the lamp has run up. The arc tube employs similar seals to all other modern ceramic metal halide lamps, based on the Philips protruding plug concept containing the usual niobium and coiled molybdenum sections. However seal stresses are somewhat greater in the higher wattage lamps, and can lead to cracks. The engineers at GS successfully developed a modified seal type that better withstands these stresses.
It makes use of a so called niobium buffer component, effectively an overwound spiral of niobium at the outermost region of the seal, which operates in a similar manner to the molybdenum spiral deeper in the seal and prevents thermal stresses from rising to levels which would ordinarily crack the seal had a solid wire been employed. Backspacing is set by a short section of niobium wire welded parallel to the feedthrough, and NGK's standard frit glass is employed.