Cascaded-signal-intensifier-based ion imaging detector for mass spectrometer

A detector system for a mass spectrometer for detecting time-dependent two-dimensional distributions of ions that exit a mass analyzer of the mass spectrometer, the detector system comprising:

• (a) a metal channel dynode (MCD) disposed within a high vacuum chamber of the mass spectrometer, said vacuum chamber comprising a wall having an aperture therethrough, said MCD comprising at least one perforated metal plate and configured to receive the exiting ions and eject electrons in response thereto;
• (b) at least one direct current (DC) power supply electrically coupled to the MCD;
• (c) an optically transparent plate or wall disposed against the vacuum chamber wall aperture and forming a vacuum seal therewith;
• (d) a phosphor coating disposed on the transparent plate or wall and within the vacuum chamber so as to receive the ejected electrons;
• (e) an image intensifier optically coupled to the transparent plate or wall so as to receive a quantity of photons generated at the phosphor coating and to emit an amplified quantity of photons proportionate to the quantity of photons:
• wherein the image intensifier comprises:
• (e1) at least one photocathode electrically coupled to the at least one DC power supply, one photocathode of the at least one photocathode optically coupled to the optically transparent plate or wall so as to receive the quantity of photons generated at the phosphor coating and to emit a proportionate quantity electrons in response thereto;
• and
• (e2) at least one electron-to-photon converter comprising:
• (e2a) a substrate plate comprising first and second parallel faces;
• (e2b) a phosphor coating on the first face of the substrate plate;
• and
• (e2c) an electrode film disposed on the phosphor coating on the first face and electrically coupled to the at least one DC power supply,
• wherein at least one phosphor coating on at least one first face is configured to receive the quantity of electrons or a different quantity of electrons generated within the image intensifier and to emit the amplified quantity of photons in response thereto;
• and
• (f) an optical detector optically coupled the image intensifier and configured so as to receive the amplified quantity of photons.