Patent ID: 7994473
Filing Date: 2011-08-09
Classification: H01J

Abstract:
1. A mass spectrometer with an electrostatic ion trap connected to a voltage supply for applying electric potentials thereto, the mass spectrometer comprising: an outer electrode having ion-repelling electric potentials applied thereto; a plurality of inner electrodes, each having an ion-attracting electric potential applied thereto, wherein the outer electrode and the inner electrodes are shaped and arranged in such a way that the electric potential between the outer electrode and the inner electrodes corresponds to a superposition of partial electric potentials of following form: wherein x, y and z are Cartesian coordinates, X=(x+x o )·cos(α), Y=(y+y o )·sin(α) and x o , y o , α, U 0 , U C , a, b, k x , k y and k z are parameters where the sum over the parameters k x , k y and k z is equal to zero, the parameter k z is larger than zero and the parameter b is not equal to zero.