US3899696A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric power generation system directly from laser power
Assignee: National Aeronautics and Space Administration
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Filing: 1974-03-27
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Granted: 1975-08-12
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Expires: 1994-03-27
Abstract
Abstract A pool of liquid cesium is spaced apart from a collector in an enclosed vessel. A laser beam is directed to the liquid cesium pool. The beam is focused to provide sufficient laser power density at the liquid cesium surface to vaporize some of the liquid cesium and ionize the vaporized cesium, and thereby form cesium ions and free electrons. The work function of the collector is different from that of cesium. When the work function is higher, the formed ions are attracted to the collector and the electrons are attracted by the liquid cesium, while the electrons and ions are respectively attracted by the collector and liquid cesium respectively when the work function of the collector is less than that of cesium. Thus, a potential difference is generated by the liquid cesium pool and the collector, sufficient to apply electric power to a load. The collector is held at a higher temperature than the liquid cesium to repel any neutralized cesium ions at the collector surface and any vaporized cesium atoms which are not ionized by the laser beam from the collector in order to facilitate the flow of ions or electrons thereto.
Inventors
- 👤 James C Administrator Fletcher
- 👤 Katsunori Shimada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:06
CPC Classifications
H; H01; H01J; H01J27/00; H01J27/02; H01J27/24; H01S; H01S3/00; H01S3/0007; H02; H02N; H02N3/00
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
91 words
A SYSTEM COMPRISING: A SOURCE OF LIQUID CESIUM A LASER FOR PROVIDING A LASER BEAM, FIRST MEANS IN THE PATH OF SAID LASER BEAM FOR DIRECTING SAID BEAM TO SAID LIQUID CESIUM, TO VAPORIZE SOME OF SAID LIQUID CESIUM AND TO IONIZE AT LAST SOME OFSAID VAPORISED CESIUM INTO CESIUM IONS AND ELECTRONS BY THE COLLISONS BETWEEN THE BEAM PHOTONS AND THE VAPORIZED CESIUM ATOMS, AND COLLECTOR MEANS ELECTRICALLY INSULATED FROM SAID LIQUID CESIUM SOURCE AND SPACED APART THEREFROM, SAID COLLECTOR MEANS HAVING A WORK FUNCTION WHICH IS DIFFERENT FROM THE
Claim 2
Independent Claim
91 words
A SYSTEM COMPRISING: A SOURCE OF LIQUID CESIUM A LASER FOR PROVIDING A LASER BEAM, FIRST MEANS IN THE PATH OF SAID LASER BEAM FOR DIRECTING SAID BEAM TO SAID LIQUID CESIUM, TO VAPORIZE SOME OF SAID LIQUID CESIUM AND TO IONIZE AT LAST SOME OFSAID VAPORISED CESIUM INTO CESIUM IONS AND ELECTRONS BY THE COLLISONS BETWEEN THE BEAM PHOTONS AND THE VAPORIZED CESIUM ATOMS, AND COLLECTOR MEANS ELECTRICALLY INSULATED FROM SAID LIQUID CESIUM SOURCE AND SPACED APART THEREFROM, SAID COLLECTOR MEANS HAVING A WORK FUNCTION WHICH IS DIFFERENT FROM THE
Claim 3
Dependent Claim
75 words
The system as described in claim 1 wherein said collector means is spaced apart from said source and the laser beam is directed to said liqiud cesium so that at least part of the laser beam reflected by said liquid cesium is directed to and impinges said collector means, said source of liquid cesium being at a temperature of not less than the melting temperature of cesium on the order of several hundred degrees K.
Claim 4
Dependent Claim
54 words
The system as described in claim 1 wherein the work function of said collector means is higher than the work function of cesium, whereby said collector means attracts the cesium ions, and said first means include means for focusing said beam at or near the top surface of the liquid cesium in said source.
Claim 5
Dependent Claim
49 words
The system as described in claim 3 wherein said collector means is spaced apart from said source and the laser beam is directed to said liquid cesium so that at least part of the laser beam reflected by said liquid cesium is directed to and impinges said collector means.
Claim 6
Dependent Claim
64 words
The system as described in claim 1 wherein the work function of said collector means is lower than the work function of cesium, whereby said collector means attracts free electrons formed when said vaporized cesium is ionized by said laser beam and said first means include means for focusing said beam at or near the top surface of the liquid cesium in said source.
Claim 7
Dependent Claim
49 words
The system as described in claim 5 wherein said collector means is spaced apart from said source and the laser beam is directed to said liquid cesium so that at least part of the laser beam reflected by said liquid cesium is directed to and impinges said collector means.
Claim 8
Independent Claim
206 words
A system comprising: a source of liquid cesium; a laser for providing a laser beam; first means in the path of said laser beam for directing said beam to said liquid cesium to vaporize some of said liquid cesium and to ionize at least some of said vaporized cesium into cesium ions and electrons by the collisions between the beam photons and the vaporized cesium atoms; and collector means electrically insulated from said liquid cesium source and spaced apart therefrom, said collector means having a work function which is different from the work function of said liquid cesium whereby either said ions or said electrons, formed when said cesium vapor is ionized, are attracted to said collector means, thereby generating a potential difference between said liquid cesium and said collector means, wherein said liquid cesium is at a temperature of not less than the melting point of cesium on the order of several hundred degrees K, and said collector means is at a temperature higher than the temperature of the liquid cesium, to repel therefrom any neutral cesium atoms present between said source and said collector means, and said laser beam is directed by said first means to said liquid cesium source through said collector means.
Claim 9
Independent Claim
206 words
A system comprising: a source of liquid cesium; a laser for providing a laser beam; first means in the path of said laser beam for directing said beam to said liquid cesium to vaporize some of said liquid cesium and to ionize at least some of said vaporized cesium into cesium ions and electrons by the collisions between the beam photons and the vaporized cesium atoms; and collector means electrically insulated from said liquid cesium source and spaced apart therefrom, said collector means having a work function which is different from the work function of said liquid cesium whereby either said ions or said electrons, formed when said cesium vapor is ionized, are attracted to said collector means, thereby generating a potential difference between said liquid cesium and said collector means, wherein said liquid cesium is at a temperature of not less than the melting point of cesium on the order of several hundred degrees K, and said collector means is at a temperature higher than the temperature of the liquid cesium, to repel therefrom any neutral cesium atoms present between said source and said collector means, and said laser beam is directed by said first means to said liquid cesium source through said collector means.
Claim 10
Dependent Claim
40 words
The system as described in claim 7 wherein said first means include means for focusing said laser beam at or near the upper surface of said liquid cesium, said laser beam ionizing only part of the cesium vaporized by it.
Claim 11
Dependent Claim
54 words
The system as described in claim 8 wherein the work function of said collector means is higher than the work function of cesium, whereby said collector means attracts the cesium ions, and said first means include means for focusing said beam at or near the top surface of the liquid cesium in said source.
Claim 12
Dependent Claim
52 words
The system as described in claim 7 wherein the collector means is spaced from said source a distance of not less than one millimeter, and positioned with respect to said source whereby at least part of the laser beam reflected by said liquid cesium is directed to and impinges said collector means.
Claim 13
Dependent Claim
29 words
The system as described in claim 10 wherein said collector means is mesh-shaped with a portion of the beam directed to said source being intercepted by said collector means.
Claim 14
Dependent Claim
40 words
The system as described in claim 11 wherein said first meAns include means for focusing said laser beam at or near the upper surface of said liquid cesium, said laser beam ionizing only part of the cesium vaporized by it.
Claim 15
Dependent Claim
54 words
The system as described in claim 12 wherein the work function of said collector means is higher than the work function of cesium, whereby said collector means attracts the cesium ions, and said first means include means for focusing said beam at or near the top surface of the liquid cesium in said source.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-08-11 | 1979-02-10 | 1979-08-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-11 | 1983-02-10 | 1983-08-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-11 | 1987-02-10 | 1987-08-12 | $7700.00 | Window Closed / Lapsed |