Patent ID: 9640378
Date: 2017-05-02
CPC Classifications: H01J

Claim:
1. A time-of-flight mass spectrometer comprising: an acceleration part for accelerating an ion generated from a sample, by an electric field; a detector disposed on a flight path of the accelerated ion after passage through the acceleration part, and configured to detect an event of arrival of the ion; and a data processing part for performing mass spectrometry of the sample, based on a time of flight of the ion to a time of detection of the event by the detector, wherein the detector includes: a micro-channel plate for multiplying electrons generated in accordance with the arrival of the ion, the micro-channel plate having an input face located at a position of the arrival of the ion, and an output face opposing the input face and outputting the multiplied electrons; a dynode disposed on the opposite side to the input face with respect to the output face and configured to multiply the electrons outputted from the output face, the dynode being set at a potential higher than a potential of the output face; and an anode disposed in a space from the dynode to an intermediate position between the output face and the dynode and configured to collect the electrons multiplied by the dynode, the anode having an aperture for letting the electrons outputted from the output face, pass toward the dynode, the anode being set at a potential higher than the potential of the dynode.