公开(公告)号：EP0212776A3

公开(公告)日：1987-08-12

申请号：EP86303400

申请日：1986-05-06

Applicant: English Electric Valve Company Limited

Inventor： Maitland, Arthur ,  Neale, Christopher Vince ,  Menown, Hugh

IPC: H01S03/03 ,  H01J01/02 ,  H01J07/08

CPC classification number: H01J61/90 ,  H01S3/03 ,  H01S3/031

Abstract: A metal vapour discharge tube includes cylindrical dispenser blocks 18 and 21 of sintered tungsten which are porous and support metal whose vapour is to form at least part of the active medium of the tube. Thus, the dispenser blocks retain the metal holding it in position in both its solid and liquid states. Heat shields 25, 26, 27 and 28 serve to retain heat within the envelope 1 of the discharge tube and uniformly heat the cylinders 18 and 21.