Patent US4649508A successfully refreshed from Google Patents.
Patent US4600840A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4600840A Expired / Lapsed US ⏱️ 0.0 years remaining

Double photon excitation of high-rydberg atoms as a long-lived submillimeter detector

Assignee: National Aeronautics and Space Administration
•
Filing: 1985-02-21
•
Granted: 1986-07-15
•
Expires: 2005-02-21
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A method and apparatus for detecting submillimeter or IR radiation is disclosed. A rare gas, such as xenon, is supplied at its ground state via a pressurized cylinder and an adjustable leak valve into a cryogenically-cooled detection area. The ground state of xenon is double-photon excited to a particularized level of the Rydberg series by a resonance lamp and a laser. The doubly-excited gas is then further excited by the radiation to be measured. A field ionization and an ion measurement indicative of the radiation intensity is achieved.

Inventors

  • 👤 Ara N. Chutjian

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 17:45
CPC Classifications
G; G01; G01J; G01J5/00; G01J5/10; G01J5/36

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 117 words
A method of submillimeter detection comprising the steps of: metering a quantity of rare gas from a pressurized cylinder into a cryogenically-cooled detection area; photon exciting the rare gas atom by first subjecting it to a resonance lamp beam selected from the same rare gas; causing a second photon excitation of the excited rare gas atom by subjecting it to a wavelength-tunable laser beam; fully exciting the double-photon excited atom, by admitting into the detection area, a source of IR or submillimeter radiation to be measured; impressing an ionization electric field across the fully excited atom; and detecting the ion created by the field ionization as a measurement of the intensity of the submillimeter or IR irradiation.
Claim 2
Independent Claim 117 words
A method of submillimeter detection comprising the steps of: metering a quantity of rare gas from a pressurized cylinder into a cryogenically-cooled detection area; photon exciting the rare gas atom by first subjecting it to a resonance lamp beam selected from the same rare gas; causing a second photon excitation of the excited rare gas atom by subjecting it to a wavelength-tunable laser beam; fully exciting the double-photon excited atom, by admitting into the detection area, a source of IR or submillimeter radiation to be measured; impressing an ionization electric field across the fully excited atom; and detecting the ion created by the field ionization as a measurement of the intensity of the submillimeter or IR irradiation.
Claim 3
Dependent Claim 32 words
A method in accordance with claim 1 wherein said metering step further comprises: adjustably opening a leak valve located in the gas supply means between the pressurized cylinder and said detection area.
Claim 4
Dependent Claim 24 words
A method in accordance with claim 1 and comprising the additional step of: pressurizing a desired amount of rare gas in a pressurized container.
Claim 5
Dependent Claim 26 words
A method in accordance with claim 1 and comprising the additional step of: selecting the rare gas from the family including xenon, krypton, argon or neon.
Claim 6
Dependent Claim 28 words
A method in accordance with claim 1 wherein the supplying step further comprises the step of: releasing the rare gas in its ground state into said detection area.
Claim 7
Dependent Claim 28 words
A method in accordance with claim 5 wherein said photon-exciting state further comprises the step of: exciting the rare gas from its ground state to an intermediate state.
Claim 8
Dependent Claim 34 words
A method in accordance with claim 6 wherein said second photon excitation step further comprises the step of: further exciting said intermediate state to a particularized level of an np or nd Rydberg series.
Claim 9
Dependent Claim 30 words
A method in accordance with claim 6 wherein said electric field-applying step further comprises the step of: selecting the field strength to ionize the excited np or nd Rydberg level.
Claim 10
Dependent Claim 119 words
A sumbillimeter detector comprising: a pressurized cylinder containing a predetermined quantitiy of a rare gas such as xenon; means for supplying a quantity of rare gas into a cryogenically-cooled detection area; resonance lamp means for photonexciting the rare gas atom by subjecting it to a beam selected from the same rare gas; a wavelength-tunable laser means for further photon-exciting the first excited rare gas atom; means admitting into the doublephoton-excited atom area a source of IR or submillimeter radiation to be measured for fully exciting the rare gas atom; means for applying an ionization electric field across the excited atom; and detecting means responsive to the ion created by the field ionization for measuring the intensity of said radiation.
Claim 11
Dependent Claim 119 words
A sumbillimeter detector comprising: a pressurized cylinder containing a predetermined quantitiy of a rare gas such as xenon; means for supplying a quantity of rare gas into a cryogenically-cooled detection area; resonance lamp means for photonexciting the rare gas atom by subjecting it to a beam selected from the same rare gas; a wavelength-tunable laser means for further photon-exciting the first excited rare gas atom; means admitting into the doublephoton-excited atom area a source of IR or submillimeter radiation to be measured for fully exciting the rare gas atom; means for applying an ionization electric field across the excited atom; and detecting means responsive to the ion created by the field ionization for measuring the intensity of said radiation.
Claim 12
Dependent Claim 27 words
A submillimeter detector in accordance with claim 9 wherein said supplying means further comprises: an adjustable leak valve connected between said pressurized cylinder and said detection area.
Claim 13
Dependent Claim 38 words
A submillimeter detector in accordance with claim 10 wherein said admitting means comprises: means for collecting submillimeter or IR radiation to be measured; and a selectively operable shutter means connected between said collecting means and said detection area.
Claim 14
Dependent Claim 27 words
A submillimeter detector in accordance with claim 9 wherein said lamp and laser means are further characterized by: coaxially directing their respective beams into said detection area.
Claim 15
Dependent Claim 31 words
A submillimeter detector in accordance with claim 12 and further characterized by: said supplying means comprising a valved source of rare gas directed along an axis which intersects said coaxiallydirected beams.

References Cited (Backward Citations)

US3764807A Cited
US3914618A Cited
US4024395A Cited
US4293769A Cited
GB2066460A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-07-14 1990-01-13 1990-07-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-07-14 1994-01-13 1994-07-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-07-14 1998-01-13 1998-07-15 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag