US3808550A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatuses for trapping and accelerating neutral particles
Assignee: AT&T Inc
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Filing: 1972-01-24
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Granted: 1974-04-30
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Expires: 1992-01-24
Abstract
Abstract There is disclosed a variety of apparatuses for controlling by radiation pressure the motion of a particle free to move with respect to its environment, based on the discovery that one or more beams of coherent optical radiation can overpower gravity and thermally induced reaction (photophoresis) forces on a small particle. The disclosed results of the effect of the radiation pressure on the motion of the particle include controllably heating the particle to provide a black-body point light source, bombardment of a sample target with small particles, very highenergy particle acceleration, strong-focusing acceleration of a neutral particle, vacuum deposition of thin films from ultrapure particles controllably vaporized while held by radiation pressure, tensile-strength testing of materials based on the radiation-pressure effect of circularly polarized light, and acceleration measurement for inertial guidance and measurement of very low gas pressures.
Inventors
- 👤 A Ashkin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 07:56
CPC Classifications
H; H05; H05H; H05H3/00; H05H3/02; H01; H01S; H01S3/00; H01S3/05; H01S3/08; G; G01; G01N; G01N30/00; G01N30/02
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
128 words
Apparatus comprising at least one particle substantially nonabsorbing for a selected range of wavelengths of optical radiation and substantially larger in its cross-sectional dimensions than said wavelength, means for supplying to said particle a field force to balance other field forces including gravitational force on said particle, said supplying means including means for supplying about said particle a diverging coherent beam of said radiation in a traveling wave of substantial intensity in said wavelength range in a direction opposed to the resultant of said other field forces to produce a radition pressure force opposed to said resultant, and means other than said supplying means for applying at least one variable force on the particle to control the motion of said particle with respect to position within said beam.
Claim 2
Dependent Claim
128 words
Apparatus comprising at least one particle substantially nonabsorbing for a selected range of wavelengths of optical radiation and substantially larger in its cross-sectional dimensions than said wavelength, means for supplying to said particle a field force to balance other field forces including gravitational force on said particle, said supplying means including means for supplying about said particle a diverging coherent beam of said radiation in a traveling wave of substantial intensity in said wavelength range in a direction opposed to the resultant of said other field forces to produce a radition pressure force opposed to said resultant, and means other than said supplying means for applying at least one variable force on the particle to control the motion of said particle with respect to position within said beam.
Claim 3
Dependent Claim
82 words
Apparatus according to claim 1 in which the means for applying at least one variable force on the particle comprises means for launching the particle into the beam, including means comprising a dielectric plate for holding said particle by Van der Waals'' forces and means for propagating acoustic energy through said plate to break said Van der Waals'' forces, said supplying means supplying said beam having a transverse mode structure for centering said particle in said beam by transverse radiation pressure forces.
Claim 4
Dependent Claim
52 words
Apparatus according to claim 1 in which the means for controlling the motion of the particle with respect to the beam comprises a vacuum chamber surrounding said particle and containing a gaseous atmosphere and means for at least partially evacuatIng said vacuum chamber to provide a selected gaseous damping for said particle.
Claim 5
Dependent Claim
92 words
Apparatus according to claim 1 in which the means for supplying a set of balancing forces includes in addition to the aforesaid beam supplying means a second means for supplying about said particle a diverging coherent traveling wave beam of said radiation in said wavelength range, and the means for controlling the motion of the particle with respect to the beam includes a vacuum chamber surrounding said particle and containing a gaseous atmosphere and means for at least partially evacuating said vacuum chamber to provide a selected gaseous damping for said particle.
Claim 6
Dependent Claim
57 words
Apparatus according to claim 1 in which the means for controlling the motion of the particle with respect to the beam comprises means for supplying about said particle a second diverging coherent traveling wave beam of radiation of substantial intensity to unbalance the balancing forces and accelerate said particle beyond the effective field of the first beam.
Claim 7
Dependent Claim
47 words
Apparatus according to claim 1 in which the particle is reflective to the diverging coherent beam of radiation and the means for supplying to the particle a field force includes means for supplying about said particle a diverging coherent beam of radiation with a doughtnut-shaped transverse mode.
Claim 8
Dependent Claim
32 words
Apparatus according to claim 5 including a plurality of apertured means for focusing said accelerating beam beyond the effective field of the first beam and for passing said particle as it accelerates.
Claim 9
Dependent Claim
60 words
Apparatus according to claim 1 in which the means for controlling the motion of the particle with respect to the aforesaid beam comprises means for supplying a plurality of unidirectional coherent optical beams intercepting said particle obliquely in its path as it accelerates and in varying orientations about said path to provide strong focusing of the particle in its path.
Claim 10
Dependent Claim
106 words
Apparatus comprising at least one particle substantially nonabsorbing for a selected range of wavelengths of optical radiation and substantially larger in its cross-sectional dimensions than said wavelength, means for supplying to said particle a field force to balance other field forces including gravitational force on said particle, said supplying means including, a plurality of lasers having resonators having mutually intersecting axes about said particle, said lasers supporting oscillations along said axes in Gaussian transverse modes for tending to center the particle with respect to said modes, at least one of said laser resonators having a horizontal axis, so that the centering tendency opposes the gravitational force.
Claim 11
Dependent Claim
106 words
Apparatus comprising at least one particle substantially nonabsorbing for a selected range of wavelengths of optical radiation and substantially larger in its cross-sectional dimensions than said wavelength, means for supplying to said particle a field force to balance other field forces including gravitational force on said particle, said supplying means including, a plurality of lasers having resonators having mutually intersecting axes about said particle, said lasers supporting oscillations along said axes in Gaussian transverse modes for tending to center the particle with respect to said modes, at least one of said laser resonators having a horizontal axis, so that the centering tendency opposes the gravitational force.
References Cited (Backward Citations)
US3489645A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-04-29 | 1977-10-29 | 1978-04-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-29 | 1981-10-29 | 1982-04-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-29 | 1985-10-29 | 1986-04-30 | $7700.00 | Window Closed / Lapsed |