| 摘要 |
<p>PURPOSE:To prevent a cathode from being poisoned and damaged due to gas emitted from an electron gun during operation by providing a non-volatile getter inside electrodes constituting an electron gun. CONSTITUTION:A non-volatile getter 16 is provided inside the second grid electrode 3 except a volatile getter 15 set up near the outside of the second grid electrode. The non-volatile getter 16 is filled in a ring-shaped container 18 while said ring-shaped container 18 is fixed to an end plate 3b on the side of the first anode of the second grid electrode 3 by electric welding. Further when the volatile getter 15 is made to be flushed after exhaust at the time of manufacture, said non-volatile getter 16 is also activated. Accordingly, emitted gas from the electron gun can be easily adsorbed thus preventing the cathode from being poisoned and damaged due to gas.</p> |
