QUADRUPLE MASS FILTER AND FEEDING PROCESS Russian patent published in 1998 - IPC

FIELD: mass spectrometry. SUBSTANCE: process of feeding of mass filter is based on supply of variable component of voltage to fore-and afterfilters, on combination of variable and constant components of supply voltage to mass filter. High-frequency voltage which envelope has form of inhomogeneous standing wave with monotone distribution of amplitude along axis of flight of ions from zero value across input of fore-and afterfilter up to value across output of fore-and afterfilter is supplied. Working surface of field-setting electrodes of fore-and afterfilters is manufactured in the form of spiral conductive tracks connected to common bus across input of forefilter and output of afterfilter and to output of forefilter and input of afterfilter connected through by-pass capacitors with working surface of electrodes of mass filter. EFFECT: increased bandwidth of mass filter for ion beam lacking parallelism at input. 2 cl, 7 dwg, 1 tbl