Gas discharge lamp has hollow plasma toroid - with diaphragm separating discharge electrodes to force discharge over longer path

摘要

The gas discharge lamp consists of two straight equal-length glass tubes and two geometrically identical U-shaped end pieces that fit into the ends of glass tubes to forms a closed ring. Before the tubes and pieces are joined together, a diaphragm (17) is inserted across the bottom of one of the U-pieces and the electrodes positioned on each side of it. The diaphragm allows mercury vapour to pass but blocks the passage of the gas discharge. The second U-piece carries the evacuation connections. The vacuum connections on the first U-piece are used to lead out the electrode wires.