| 摘要 |
PURPOSE:To prevent a secondary electron multiplying plate from being deformed by directing a component of force applied to said multiplying plate by a metal spring in a direction where said plate is pressed onto a metal ring body, and in a direction from the center toward the outer periphery of the plate along the surface thereof. CONSTITUTION:A secondary electron multiplying plate (MCP)3 is supported and fixed on a metal ring body 8 by a metal ring body 7 via a sleeved ring spring 14. The spring 14, made of a metal spring material, is ring-shaped partly cut away, and is open-grooved 17 in its cross section toward the outside. The diameter of the ring is made approximately equal to the inner diameter of ceramic 11. After placing the MCP3 on the ring body 8, the spring 14 is brought about on the MCP and slipped in between the MCP3 and the ring body 7 to support the MCP3 while forcing both ends 15, 16 of the cut away portion so as to allow them to overlap with each other and thereby reducing the diameter of the ring and making use of a spring action which serves to expand the diameter of the spring 14 in itself. The MCP3 at this time is subjected to two forces, one C for pressing the MCP onto the ring body 8 and the other directed from the center to the outside, thus preventing the MCP from being deformed. |
