Compact fluorescent lamp and method for manufacturing

Method for manufacturing a compact fluorescent lamp comprising the steps of:

• a) providing an outer envelope comprising a substantially spherical portion and an elongated end portion being terminated by an open end on a base side;
• b) closing and sealing the open end of the elongated portion of the envelope with a seal of the same material as the material of the outer envelope to provide a hermetic seal, the seal also comprising power supply lead-out wires and an exhaust tube;
• c) subsequently separating the envelope by cutting along a circumferential separating line along the elongated end portion in a plane substantially perpendicular to a principal axis of the envelope into an upper part for receiving a discharge tube arrangement having a maximum cross-sectional, first dimension less than a cross-sectional, second dimension of the elongated end portion of the outer envelope for receiving the discharge tube arrangement therethrough with lead-in wires and a lower part closed by the seal at the base side for receiving a ballast circuit with connection points for the power supply lead-out wires and lead-in wires of the discharge tube arrangement;
• d) next introducing the ballast circuit into the lower part and connecting the respective connection points of the ballast circuit to the power supply lead-out wires;
• e) connecting the lead-in wires of the discharge tube arrangement to the respective connection points of the ballast circuit;
• f) after the ballast circuit, lead-out wires, and lead-in wire connections have been completed, bringing the two separated parts of the envelope along the separating line into contact with each other;
• g) subsequently connecting and sealing the upper and lower part of the envelope along the separating line;
• h) providing the envelope with a base;
• and
• i) connecting the lead-out wires to contact terminals of the base.