| 摘要 |
PURPOSE:To improve the focusing property and the resolution capability of ions, by converting the condition of stable mass without disturbing the inside of a quadruple electric field, when ions trapped in the quadruple electric field are picked out. CONSTITUTION:The DC voltage U and the amplitude V of the high-frequency voltage are determined to pass the mass locus (h) near the crossing point (m) of the Z-axis stabilization border line Z of the mass (m) in respect of the all mass in the ion stabilization area and the radial direction stabilization border line (rm) of the ions of the mass (m), and by converting the both voltages maintaining the proportional relation, the point (m) of the mass scale on the mass locus comes to be at the point (m) in the figure. By setting the U and V in such a way, the ions of the mass (m) are trapped in a quadruple electrical field, and the ions of the mass larger than (m) go out below the Z-axis stabilization border line Z being scattered in an unstable condition. The ions with the mass smaller than (m) are scattered in an unstable condition in the radius direction. Therefore, the focus property of ions is improved, and moreover, the resolution capability is also improved. |
