Development of a Miniature Double Focusing Mass Spectrograph Using a Focal Plane Detector

摘要

A miniature mass spectrograph was newly designed and constructed as a prototype model for future lunar or planetary explorations. The ion optical system was newly designed based on Mattauch-Herzog geometry. The mass spectrograph employs a focal plane detector consisting of a microchannel plate (MCP), a phosphor layer, a fiber-optic plate (FOP) and a charge-coupled device (CCD). The 2D and 1D spectra of the residual gases, krypton and neon were observed in preliminary experiments. The mass resolution of 130 was achieved experimentally, and this was in good agreement with the simulation based on the transfer matrix method. The experimental value of the detectable m/z range was also consistent with the calculated version. Moreover, stable isotopes of Kr and Ne were observed without saturation of the detector. A dynamic range of 300 was achieved.