Patent US3757251A successfully refreshed from Google Patents.
US3757251A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Laser direct current auxiliary ionization of an axially excited flowing gas
Assignee: RTX Corp
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Filing: 1971-07-21
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Granted: 1973-09-04
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Expires: 1991-07-21
Abstract
Abstract A high efficiency electric discharge gas laser which is capable of high power pulses and high repetition rates is disclosed. A region of high electrical conductance is provided in a laser gas along the axis of the laser optical cavity by a low current auxiliary ionization discharge, and a high voltage, high current pulsed power source produces an electric plasma having a population inversion throughout the region. Fins are positioned in the cavity to confine the cross section of the plasma and to maintain the plasma around the cavity axis. In one configuration in which the gas flow is transverse to the optical axis, a magnetic field which is orthogonal to both the direction of gas flow and the optical axis is used to counteract the downstream bowing effect in the plasma caused by the gas flow. In a high pressure embodiment of the invention, multiple electric discharges are arranged in parallel along the axis of the laser to provide the necessary pumping of the laser gas.
Inventors
- 👤 R Freiberg
- 👤 C Buczek
- 👤 P Chenausky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 19:11
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/09; H01S3/097; H01S3/0971; H01S3/09713
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
182 words
In the method of operating a pulsed gas laser in which gas is electrically exicted in the resonant optical cavity of the laser, said cavity having a characteristic internal, self consistent, electromagnetic field laser mode distribution configuration and an optical axis about which a pair of spaced apart hollow electrodes is coaxially disposed, the steps of: flowing a quantity of the gas between said electrodes in a direction which is transverse to the optical axis; providing a continuous direct current electric discharge between said electrodes to ionize the gas therebetween and provide a region of high electrical conductance in the cavity along said axis; providing a pulsed electric current discharge in said region of high conductance between the electrodes to produce in the cavity an electric plasma having a population inversion whereby stimulated emission of pulsed laser energy is produced; positioning the plasma substantially parallel to the optical axis; confining the cross-sectional area of the plasma to substantially the cross-sectional area of the mode distribution; and applying a magnetic field transverse to both the optical axis and the direction of gas flow.
Claim 2
Dependent Claim
182 words
In the method of operating a pulsed gas laser in which gas is electrically exicted in the resonant optical cavity of the laser, said cavity having a characteristic internal, self consistent, electromagnetic field laser mode distribution configuration and an optical axis about which a pair of spaced apart hollow electrodes is coaxially disposed, the steps of: flowing a quantity of the gas between said electrodes in a direction which is transverse to the optical axis; providing a continuous direct current electric discharge between said electrodes to ionize the gas therebetween and provide a region of high electrical conductance in the cavity along said axis; providing a pulsed electric current discharge in said region of high conductance between the electrodes to produce in the cavity an electric plasma having a population inversion whereby stimulated emission of pulsed laser energy is produced; positioning the plasma substantially parallel to the optical axis; confining the cross-sectional area of the plasma to substantially the cross-sectional area of the mode distribution; and applying a magnetic field transverse to both the optical axis and the direction of gas flow.
Claim 3
Dependent Claim
202 words
A gas laser apparatus for providing a pulsed output of laser energy with a gas working medium comprising: a resonant optical cavity having an optical axis and a characteristic, internal, self consistent, electromagnetic field laser mode distribution and capable of providing an output of pulsed laser power from an electrically excited gas; a pair of hollow electrodes coaxially disposed about the optical axis; means for delivering the gas to and removing the gas from the cavity and for flowing the gas in a direction which is transverse to the optical axis; means for applying to said electrodes a continuous electric current which is capable of producing a region of high electrical conductance along said axis in the gas provided to said cavity; means for applying a pulsed electric current to said electrodes to produce along said axis an electric plasma having a population inversion which is capable of lasing; means location in the flowing gas for positioning the plasma with respect to the optical axis and confining the cross section of the plasma to substantially match the cross section of said mode distribution; and means providing a magnetic field transverse to both the optical axis and the direction of the gas flow.
Claim 4
Dependent Claim
202 words
A gas laser apparatus for providing a pulsed output of laser energy with a gas working medium comprising: a resonant optical cavity having an optical axis and a characteristic, internal, self consistent, electromagnetic field laser mode distribution and capable of providing an output of pulsed laser power from an electrically excited gas; a pair of hollow electrodes coaxially disposed about the optical axis; means for delivering the gas to and removing the gas from the cavity and for flowing the gas in a direction which is transverse to the optical axis; means for applying to said electrodes a continuous electric current which is capable of producing a region of high electrical conductance along said axis in the gas provided to said cavity; means for applying a pulsed electric current to said electrodes to produce along said axis an electric plasma having a population inversion which is capable of lasing; means location in the flowing gas for positioning the plasma with respect to the optical axis and confining the cross section of the plasma to substantially match the cross section of said mode distribution; and means providing a magnetic field transverse to both the optical axis and the direction of the gas flow.
Claim 5
Dependent Claim
87 words
The laser according to claim 2 wherein said means for positioning and confining the cross section of the plasma comprises a plurality of fins which are spaced apart from one another and positioned perpendicular to the optical axis, between said electrodes, each fin having a hole therein and extending at least several hole diameters on either side of the hole in the flow direction, each hole being disposed symmetrically about said axis and having a cross section substantially identical with the cross section of said mode distribution.
Claim 6
Dependent Claim
138 words
In a flowing gas laser apparatus which includes: a resonant optical cavity having an optical axis and a characteristic, internal, self consistent, electromagnetic field, laser mode distribution; electrodes coaxially disposed about the optical axis; means for delivering gas to and removing the gas from the cavity; and means for establishing an electric potential between the electrodes to produce an electric plasma along the axis, the improvement comprising: means for positioning and confining the cross section of the plasma comprising a plurality of fins which are spaced apart from one another and positioned perpendicular to the optical axis, each fin having a hole therein and extending at least several hole diameters on either side of the hole which is disposed symmetrically about the axis and has a cross section substantially identical with the cross section of the mode distribution.
Claim 7
Dependent Claim
138 words
In a flowing gas laser apparatus which includes: a resonant optical cavity having an optical axis and a characteristic, internal, self consistent, electromagnetic field, laser mode distribution; electrodes coaxially disposed about the optical axis; means for delivering gas to and removing the gas from the cavity; and means for establishing an electric potential between the electrodes to produce an electric plasma along the axis, the improvement comprising: means for positioning and confining the cross section of the plasma comprising a plurality of fins which are spaced apart from one another and positioned perpendicular to the optical axis, each fin having a hole therein and extending at least several hole diameters on either side of the hole which is disposed symmetrically about the axis and has a cross section substantially identical with the cross section of the mode distribution.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-09-03 | 1977-03-05 | 1977-09-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-03 | 1981-03-05 | 1981-09-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-03 | 1985-03-05 | 1985-09-04 | $7700.00 | Window Closed / Lapsed |