Ion Optics of Sector-Type Magnetic Focusing Fields

Abstract

The convergence of the ion beam in the sector-type magnetic focusing field of the mass spectrometer is treated geometrically. The real thickness of the ion beam was considered, and the ratio of the radius of deflection to the beam thickness is included as a common parameter in the expression for the final image width. The treatment is composed of three parts : the first order approximation, the second order approximation and the complete convergence. In conclusion, a new type of optical system consisting of a dual arrangement of circular magnetic fields, is proposed and given the name “Collimatron” optical system.