| 摘要 |
PURPOSE:To facilitate the attachment and detachment of an annular hot cathode in a hot-cathode electron impact type ion source for a tetrode analyzer by installing the hot cathode independently of an anode by integrating the hot cathode with electron diaphragm electrodes through an insulating material. CONSTITUTION:After grid-like or mesh-like anode 2 is attached to an anodic base plate 11, an annular hot cathode 3 is installed around the anode 2. At the same time, an electron diaphragm electrode 4 is installed between the anode 2 and the cathode 3, thereby constituting a hot-cathode electron impact type ion source for a tetrode analyzer. Here, after an insulating terminal 6 is attached to an electron diaphragm electrode base plate 5 placed over the anode base plate 11 insulatedly from it, the annular hot cathode 3 is fixed to a terminal vertically extending from the terminal 6. As a result, the hot cathode 3 is installed independently of the anode 2 by integrating the hot cathode 3 with the electron diaphragm electrodes 4 and 5 through the insulating terminal 6. Accordingly, it is possible to facilitate the replacement of the hot cathode 3 by simplifying its attachment and detachment. |
