US 6,982,417 B2 | ||
Method and apparatus for detecting low-mass ions | ||
Michel J. Adrien Baillargeon, Bartlesville, Okla. (US) | ||
Assigned to Siemens Energy & Automation, Inc., Alpharetta, Ga. (US) | ||
Filed on Oct. 09, 2003, as Appl. No. 10/681,947. | ||
Prior Publication US 2005/0077466 A1, Apr. 14, 2005 | ||
Int. Cl. B01D 59/44 (2006.01) |
U.S. Cl. 250—292 | 34 Claims |
15. An apparatus for inducing ions of a predetermined mass-to-charge ratio to orbit at a resonant frequency, comprising:
a digital signal processor (DSP) configured to output a digital signal comprising a fundamental frequency;
a digital-to-analog converter (DAC) connected to the DSP for converting the digital signal to an analog excitation signal
including the fundamental frequency and at least one secondary frequency greater than the fundamental frequency, the at least
one secondary frequency including the resonant frequency; and
excitation plates connected to the DAC for applying the excitation signal to the ions.
|