The United States of America as Represented by the United States

Mark W West

Ka-Ngo Leung

Malcom D Williams

David Moussa

Stephen B Wilde

Keith C Gordon

Dean O Kippenham

Peter Purgalis

A large area directly heated lanthanum hexaboride (LaB.sub.6) cathode system (10) is disclosed. The system comprises a LaB.sub.6 cathode element (11) generally circular in shape about a central axis. The cathode element (11) has a head (21) with an upper substantially planar emission surface (23), and a lower downwardly and an intermediate body portion (26) which diminishes in cross-section from the head (21) towards the base (22) of the cathode element (11). A central rod (14) is connected to the base (22) of the cathode element (11) and extends along the central axis. Plural upstanding spring fingers (37) are urged against an outer peripheral contact surface (24) of the head end (21) to provide a mechanical and electrical connection to the cathode element (11).

Large area directly heated lanthanum hexaboride cathode structure having

Growing community of inventors

Albany, CA, United States of America

Mark W West