| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To suppress the rise of temperature of an inner conductor of a hot cathode having a coaxial structure to thereby extend the life time of the inner conductor and thus to extend the life time of the hot cathode. <P>SOLUTION: The hot cathode 10 includes a hollow external conductor 2, a hollow inner conductor 1 coaxially disposed inside the external conductor 2, and a connection conductor 3 electrically connecting the conductors 1 and 2. A heating current I<SB>H</SB>is made to turn back via the connection conductor 3, such that the heating current I<SB>H</SB>flows through the external conductor 2 in the direction opposite to the direction in which the heating current I<SB>H</SB>flows through the inner conductor 1. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
