Charged particle detector , time-of-flight mass spectrometer

摘要

PROBLEM TO BE SOLVED: To provide a charged-particle detector and a time-of-flight mass spectrometer capable of preventing a detection error due to secondary electrons generated at a grid electrode arranged on the upstream side in the incident direction of ions of MCP (microchannel plate).;SOLUTION: A charged-particle detector X which detects ions to be incident by making the ions pass through MCPs 11,12 is arranged to face the incidence plane 11a of ions on the MCP 11 and has a grid electrode 2 with a potential Vg lower than the potential Vin of the incidence plane 11a. And the grid electrode 2 has a function of moving secondary electrons, generated when ions are applied to the grid electrode 2, in a separating direction with respect to the incidence plane 11a of the MCP 11. For example, the grid electrode 2 is formed by a plurality of grid lines 21 with a triangle cross-sectional shape tapering to the MCP 11 from the upstream side to the downstream side in the incident direction of ions.;COPYRIGHT: (C)2012,JPO&INPIT