Patent ID: 8080785

Claim:
A high pressure collision cell for use in a mass spectrometer, comprising: a) a first housing enclosing a first chamber including first and second opposed elongate electrically conducting electrodes each having an aperture and spaced apart a length L thereby defining a collision cell length, each of said first and second opposed elongate electrically conducting electrodes forming an electrostatic lens, said first and second opposed elongate electrically conducting electrodes being positioned with respect to each other so that said apertures in each are generally aligned along a transverse flow axis through said first chamber between said first and second opposed elongate electrically conducting electrodes; b) chamber walls between said first and second opposed elongate electrically conducting electrodes to enclose said first chamber, said chamber walls being electrically isolated from said first and second opposed elongate electrically conducting electrodes and being sealed to said first and second opposed elongate electrically conducting electrodes in such a way as to provide a pressure seal; c) a gas injection port on said housing for injecting an inert gas into said first chamber, a pumping port on said first housing and a pump for pumping said inert gas out of said first chamber; d) a power supply for applying a selected voltage to said first and second opposed elongate electrically conducting electrodes; and e) said collision cell length L selected to be in a range such that upon application of said selected voltage to said first and second opposed elongate electrically conducting electrodes there is produced an electric field of sufficient strength across said collision cell length L in said first chamber to aid in directing ions across said collision cell length L along said transverse flow axis; and f) pressure controller for maintaining a pressure in said collision cell in a range from about 50 mTorr to 1000 mTorr and wherein said collision cell length L and said pressure are selected such that a target thickness, defined as a product of the collision cell length and the pressure, is maintained in a range from about 0.2 to about 2 mm-Torr.