Inventors:
Galina Zilberstein - Chestnut Hill MA
James A. Avallon - Beverly MA
John W. Shaffer - Danvers MA
Assignee:
Osram Sylvania Inc. - Danvers MA
International Classification:
H01J 938
H01J 944
Abstract:
A method for recrystallization of tungsten filaments for incandescent lamps includes the steps of providing a tungsten filament fixed to lead-in wires, providing a light-transmitting glass envelope having a closed first end and an open second end, the first end being closed by an envelope press portion integral with the remainder of the envelope, the press portion having the lead-in wires sealed therein and extending therethrough into the envelope, introducing a forming gas into the envelope, flushing the envelope with infusions of the forming gas, flashing the filament in the presence of the forming gas to recrystallize the filament, evacuating the forming gas from the envelope, introducing fill gas into the envelope, and closing the envelope second end.