CHARGED PARTICLE DEFLECTING SYSTEM

PROBLEM TO BE SOLVED: To efficiently introduce to a mass spectrometer by utilizing the difference in electric field intensities based on a gap between first and second electrode plates and converging positively charged particle group deflected with the electrode plate and having different energy. SOLUTION: A charged particle group generated in a charged particle generating source 1 is converged with an electric field lens 12, and enters a gap between an electrode plate 3 and a second electrode plate 4 from an opening of a first electrode plate 3. Positively charged particles 7 are separated from negatively charged particles with an electric field which faces the electrode plate 3 from the electrode plate 4 and are curved toward wider space. The inclined angles of the electrode plates 3, 4 are made different, and a gap produced between the different inclined angles is tapered so as to be narrowed as it goes upward, positively charged particles 7 having large energy which is hardly deflected reach further upward, but decelerated as they approach upward, an electric field intensity contributing to deflection is enhanced, and highly deflected. As a result, the positively charged particles 7 are converged in positions having different energy.