KOMPAKTE NIEDERDRUCKQUECKSILBERDAMPFENTLADUNGSLAMPE UND VERFAHREN ZU DEREN HERSTELLUNG

Acompact low-pressure mercury vapour discharge lamp comprises two or more straight tubes (2, 3) which are interconnected by means of couplings (4), to form a discharge chamber between two electrodes (15). The electrodes are located in the outermost ends (7,8) of the discharge chamber of the lamp, these ends being connected in a gas-tight manner to a lamp base (9) incorporating the requisite contact pins (11, 12) and conductors (16).Located downstream of the electrodes (15) in the direction of the discharge current are tube constrictions (13, 14) which define around the electrodes (15) the spaces in which released ions from the electrode emission material are held concentrated, so as to fall back onto the electrode surface upon a change in current phase.The method for manufacturing the lamp commences with a straight glass tube which is coated internally with luminescent powder. The tube is then heated around annular areas adjacent the tube ends. The constrictions (13, 14) are formed in the tube wall as the tube rotates, whereafter the lamp is manufactured in a manner known per se.