Low-pressure mercury vapour discharge lamp.

摘要

A low-pressure mercury vapour discharge lamp having a tungsten coil electrode (9) which is supported at either end by a respective current supply wire (8) and which has emitter-coated central turns (9a) and, on either side thereof, end turns which are free from emitter (9b). Each of the current supply wire ends with adjoining end turns of the coil is surrounded by an electrically insulating sleeve (10), such as a glass tube, as a result of which the switching life of the lamp is considerably increased. <IMAGE>