COIL ARRANGEMENT FOR ADJUSTING THE FOCUS AND/OR CORRECTING THE ABERRATION OF STREAMS OF CHARGED PARTICLES BY ELECTROMAGNETIC DEFLECTION, PARTICULARLY FOR SECTOR FIELD LENSES IN MASS SPECTROMETERS

摘要

A coil arrangement for adjusting the focus and/or correcting the aberration of streams of charged particles by electromagnetic deflection, particularly for sector field lenses in mass spectrometers, comprises flat coils produced in accordance with conventional printed circuit technology. Part of the turns of each coil is shaped to produce a locally changing magnetic field normal to the stream of charged particles for differentially affecting the particle paths according to their position in this magnetic field.