Patent ID: 6465779
Filing Date: 2002-10-15
Classification: H01J

Abstract:
A method of mass analyzing for ions using a mass spectrometer with an endcap electrode, comprising the steps of:producing ions from a sample by an ion source; optimizing a second voltage Vâ€² applied to said endcap electrode and a drift voltage V; applying the optimized drift voltage V to the ions produced by said ion source; applying the optimized second voltage Vâ€² to the ions after the optimized drift voltage V was applied to said ions; mass analyzing said ions; wherein said step of optimizing said drift voltage V and said second voltage Vâ€² comprising: a step of changing said drift voltage V by an increment &Dgr;V; a step of changing said second voltage Vâ€² by an increment &Dgr;Vâ€² which is obtained by multiplying a predetermined coefficient C to the increment &Dgr;V of said drift voltage V.