US3740552A
Expired / Lapsed
US
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Method and apparatus for mass separation employing photo enhanced surface ionization
Assignee: Individual
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Filing: 1971-04-29
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Granted: 1973-06-19
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Expires: 1991-04-29
Abstract
Abstract Photo-assisted surface ionization techniques are employed for the separation of isotopes and the purification of materials, the formation of relatively pure and intense ion beams and plasmas and the detection of minor constituents, pollutants and leaks. A species intermingled with other constituents in an atomic or molecular beam or in a gas, for example, is selectively excited by irradiation at a resonance frequency in close proximity to an ionizing surface. The selected species, while still in the excited level, interacts with the surface and is ionized. The specimen is excited by the radiation to a level such that the energy required to ionize the atom is less than the work function of the solid surface.
Inventors
- 👤 J Pressman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 10:45
CPC Classifications
H; H01; H01J; H01J49/00; H01J49/02; H01J49/10; H01J49/16; H01J49/161; B; B01; B01D; B01D59/00; B01D59/34
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
93 words
The method of separating certain particles which absorb radiation of one frequency from other particles that absorb radiation of different frequencies, comprising the steps of directing all Types of said particles against an ionizing surface and irradiating in close proximity to the ionizing surface all of said particles with electromagnetic energy of said one frequency whereby said certain particles are selectively excited to a level less than the work function of said surface to be surface ionized upon contact with said surface, and then separating the surface ionized particles from all other particles.
Claim 2
Independent Claim
93 words
The method of separating certain particles which absorb radiation of one frequency from other particles that absorb radiation of different frequencies, comprising the steps of directing all Types of said particles against an ionizing surface and irradiating in close proximity to the ionizing surface all of said particles with electromagnetic energy of said one frequency whereby said certain particles are selectively excited to a level less than the work function of said surface to be surface ionized upon contact with said surface, and then separating the surface ionized particles from all other particles.
Claim 3
Dependent Claim
10 words
The method of claim 1 wherein said energy is light.
Claim 4
Dependent Claim
12 words
The method of claim 2 wherein said light is a laser beam.
Claim 5
Dependent Claim
15 words
The method of claim 1 wherein said particles are in the form of a beam.
Claim 6
Dependent Claim
15 words
The method of claim 1 wherein said particles are in the form of a gas.
Claim 7
Dependent Claim
15 words
The method of claim 1 wherein said particles and said surface are in a vacuum.
Claim 8
Dependent Claim
14 words
The method of claim 1 including the step of collecting the surface ionized particles.
Claim 9
Dependent Claim
21 words
The method of claim 7 wherein said surface ionized particles are formed into a plasma beam and focussed into a receptacle.
Claim 10
Dependent Claim
10 words
The method of claim 1 wherein said energy is pulsed.
Claim 11
Dependent Claim
10 words
The method of claim 1 wherein said energy is continuous.
Claim 12
Dependent Claim
16 words
The method of claim 1 including the step of measuring electrical current flow at said surface.
Claim 13
Dependent Claim
113 words
Apparatus for separating certain particles which absorb electromagnetic radiation of one frequency from other particles that absorb radiation of different frequencies, comprising a. a housing, b. a member of selected material in said housing and providing an ionizing surface, c. means for directing particles against said surface, d. means for heating said surface, e. radiation means for irradiating said particles in close proximity to said surface with radiation of said one frequency whereby said certain particles will be selectively excited to a level less than the work function of said surface to be surface ionized upon contact with said surface, and, f. means for separating the surface ionized particles from all other particles.
Claim 14
Dependent Claim
113 words
Apparatus for separating certain particles which absorb electromagnetic radiation of one frequency from other particles that absorb radiation of different frequencies, comprising a. a housing, b. a member of selected material in said housing and providing an ionizing surface, c. means for directing particles against said surface, d. means for heating said surface, e. radiation means for irradiating said particles in close proximity to said surface with radiation of said one frequency whereby said certain particles will be selectively excited to a level less than the work function of said surface to be surface ionized upon contact with said surface, and, f. means for separating the surface ionized particles from all other particles.
Claim 15
Dependent Claim
15 words
Apparatus according to claim 12 wherein said radiation means is tuneable to different discrete frequencies.
Claim 16
Dependent Claim
12 words
Apparatus according to claim 12 wherein said radiation means is a laser.
Claim 17
Dependent Claim
48 words
Apparatus according to claim 14 including a plurality of spaced ionizing surfaces in said housing and optical means operatively associated with said laser for dividing said laser beam into a plurality of separate beams and forming each said separate beam into proximity to each of said spaced surface.
Claim 18
Dependent Claim
12 words
Apparatus according to claim 15 wherein said optical means includes optical fibers.
Claim 19
Dependent Claim
11 words
Apparatus according to claim 15 wherein said optical means include mirrors.
Claim 20
Dependent Claim
15 words
Apparatus according to claim 12 including evacuating means connected to said housing for evacuation thereof.
Claim 21
Dependent Claim
20 words
Apparatus according to claim 12 wherein said directing means includes an oven adapted to generate a beam of said particles.
Claim 22
Dependent Claim
17 words
Apparatus according to claim 12 including collection means in said housing for collecting the selectively ionized particles.
References Cited (Backward Citations)
US3443087A
Cited
US3479545A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-06-18 | 1976-12-18 | 1977-06-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-18 | 1980-12-18 | 1981-06-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-18 | 1984-12-18 | 1985-06-19 | $7700.00 | Window Closed / Lapsed |