Claims
- 1. A system comprising emission means for emitting a beam of ions said emission means comprising:
- a cylindrical first housing having an axis extending longitudinally in said first housing and first and second ends, said first housing being closed at said first end and open at said second end through which ions are emitted;
- gas insertion means positioned in said closed first end for injecting at least one gas into said first housing;
- electron emission means positioned near said first end of said first housing for emitting electrons;
- electron repulsion means, including a first grid positioned between said closed first end of said first housing and said first electron emission means for repelling said electrons away from said first end of said first housing;
- first biasing means for adjustably applying a negative voltage to said electron emission means and said electron repulsion means with respect to said first housing;
- a first cylinder having first and second ends and of a smaller diameter than said first housing, said first cylinder concentrically positioned within said first housing, with said first end of said first cylinder adjacent said first electron emission means;
- second biasing means for adjustably applying a positive voltage to said first cylinder with respect to said first housing;
- second and third grids connected across said first and second ends, respectively, of said first cylinder and in electrical contact with said first cylinder, said first cylinder and said second and third grids defining a positively biased ionization chamber therein;
- a plurality of separately energizable coils around and serially positioned along said first cylinder, whereby, when said coils are energized, a region of magnetic repulsion to electrons is formed in said first cylinder adjacent said second end, and, in combination with said electron repulsion means, forms a region for confining electrons therebetween;
- a fourth grid positioned in a region exterior and adjacent said second end of said first cylinder; and
- third biasing means for adjustably applying a negative voltage to said fourth grid, said last-named negative voltage being with respect to the positive voltage applied to said first cylinder.
- 2. A system as set forth in claim 1 comprising;
- a fifth grid positioned in a region adjacent to and spaced from said fourth grid; and
- fourth biasing means for adjustably applying a negative voltage to said fifth grid, said last-named negative voltage being with respect to the positive voltage applied to said first cylinder.
- 3. A system as set forth in claim 2 comprising:
- a first electrically heated, U-shaped filament spaced from said fifth grid and positioned adjacent said first end of said cylindrical first housing; and
- fifth biasing means for adjustably applying a negative voltage to said first U-shaped filament with respect to said first housing.
- 4. A system as set forth in claim 1 further comprising a drift tube, in turn comprising:
- a tubular second housing having first and second ends, said first end of said second housing coupled to said second end of said first housing, and through which said ions enter said drift tube;
- at least one electrically conductive second cylinder positioned within said second housing;
- a sixth grid positioned in said second housing adjacent said second end of said second housing, and through which said ions exit said drift tube;
- a gaseously sealable enclosure having an opening, and said second end of said second housing being coupled to said last-named opening;
- movable support means positioned within said enclosure for supporting and moving an instrument being tested;
- beam analyzing means movably supported within said enclosure for analyzing said beam of atomic particles; and
- pumping means for evacuating said first housing and said second housing and said enclosure and creating a vacuum therein.
- 5. A system as set forth in claim 4 wherein said drift tube comprises:
- second and third conductive cylinders serially arranged in said tubular second housing;
- fourth and fifth biasing means for adjustably applying positive voltages to said second and third cylinders, respectively, with respect to said first housing; and
- valve means positioned between said third and fourth cylinders, whereby a vacuum is continuously maintained in said first housing and in a portion of said drift tube adjacent said first housing.
- 6. A system as set forth in claim 1 wherein said electron emission means comprises a spirally-configured tungsten filament circularly formed about said axis of said cylindrical first housing.
- 7. A system as set forth in claim 5 wherein said second and third cylinders are constructed of a ferrous alloy.
- 8. A system as set forth in claim 5 comprising a second U-shaped, electrically heated filament spaced from said sixth grid and positioned adjacent said opening in said enclosure.
ORIGIN OF THE INVENTION
The invention described herein was made by employees of the United States Government and may be manufactured and used by or for the Government for Government purposes without the payment of any royalties thereon or therefor.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
3619684 |
Andrew et al. |
Nov 1971 |
|
Non-Patent Literature Citations (1)
Entry |
Abdrashitova et al., Sov. Phys. Tech. Phys., vol. 19, No. 2, Aug. 1974, pp. 264-266. |