| abstract |
An apparatus for analyzing chemical species, comprising: (a) an ion source fornproducing ions from a sample substance; (b) a vacuum region, said vacuum regionncomprising at least two vacuum stages (183, 184, 185, 186), each of said vacuumnstages (183, 184, 185, 186) having means for pumping away gas to produce anpartial vacuum, said vacuum stages (183, 184, 185, 186) being in communicationnwith each other such that said ions can move through a sequence of said vacuumnstages (183, 184, 185, 186); (c) a Time-of-Flight mass analyzer (192) having andetector, said Time-of-Flight mass analyzer (192) being located in at least onen(186) of said vacuum stages (183, 184, 185, 186); (d) at least one multipole ionnguide (180, 181) located in said vacuum region; and (e) means for applyingnelectrical voltages to said at least one multipole ion guide; characterized in that:nsaid ion source operates substantially at atmospheric pressure. |