| 摘要 |
The charged particle selector includes first and second coaxial conducting discs (18, 20), lying spaced apart and parallel. Between the discs there is an electric field. The first disc (18) includes an annular slot (22) communicating with the atmosphere to be analysed, and the second includes a central extraction orifice. Midway between the two discs there is a third disc, also having an annular slot (28) at a smaller radius than that of the first disc. There is provision to provide a laminar flow of filtered air in a radial direction (90). <IMAGE> |
