US3814983A
Expired / Lapsed
US
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Apparatus and method for plasma generation and material treatment with electromagnetic radiation
Assignee: POLYPLASMA Inc 630 DORCHESTER BLVD WEST SUIT 2520 MONTREAL PROVINCE OF QUEBEC CANADA H3B 4H6 A CORP OF CANADA
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Filing: 1972-02-07
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Granted: 1974-06-04
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Expires: 1992-02-07
Abstract
Abstract Apparatus for generating plasmas using electromagnetic energy in the microwave frequency range, having a source of microwave energy, a slow wave structure, conveying means for conveying microwave energy from the source to the slow wave structure, a plasma container and means for maintaining conditions of pressure and gas flow in the container. There is also provided a novel transparent radiation shield for use with such an apparatus. In another embodiment, there is also provided a slow wave structure and microwave energization means so that a region adjacent the structure will contain a predominance of degenerate pi /2 mode or near degenerate pi /2 mode electric field energy. Methods are also disclosed for treating various types of material to alter their properties using the above-described apparatus.
Inventors
- 👤 C Weissfloch
- 👤 M Wertheimer
- 👤 R Bosisio
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 06:21
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/32; H01J37/32009; H01J37/32192; G; G21; G21K; G21K5/00; G21K5/10; H01J37/32211; H01J65/00; H01J65/04; H01J65/042; H01J65/044; H05; H05H; H05H1/00; H05H1/24; H05H1/46; H05H1/461; H05H1/4622
Claims Analysis
Total Claims: 46
Claim 1
Independent Claim
158 words
An apparatus for generating a plasma using electromagnetic energy in the microwave frequency range comprising a source of microwave energy, at least one slow wave structure having an input end for receiving microwave energy from the source thereof, means for conveying said microwave energy from said source of said microwave energy to the input end of said slow wave structure to create a region adjacent said slow wave structure containing electromagnetic energy, a plasma container spaced from and located in proximity to said slow wave structure in the region containing electromagnetic energy, said plasma container being adapted to receive an ionizable gaseous fluid so that the microwave energy is applied to said gaseous fluid to generate a plasma therefrom, means for maintaining conditions of pressure and flow of said ionizable gaseous fluid in said plasma container, and said slow wave structure having an output end for discharging certain of the microwave energy traveling along said slow wave structure.
Claim 2
Independent Claim
158 words
An apparatus for generating a plasma using electromagnetic energy in the microwave frequency range comprising a source of microwave energy, at least one slow wave structure having an input end for receiving microwave energy from the source thereof, means for conveying said microwave energy from said source of said microwave energy to the input end of said slow wave structure to create a region adjacent said slow wave structure containing electromagnetic energy, a plasma container spaced from and located in proximity to said slow wave structure in the region containing electromagnetic energy, said plasma container being adapted to receive an ionizable gaseous fluid so that the microwave energy is applied to said gaseous fluid to generate a plasma therefrom, means for maintaining conditions of pressure and flow of said ionizable gaseous fluid in said plasma container, and said slow wave structure having an output end for discharging certain of the microwave energy traveling along said slow wave structure.
Claim 3
Dependent Claim
23 words
An apparatus, as defined in claim 1, said apparatus including a dummy load connected to the output end of said slow wave structure.
Claim 4
Dependent Claim
30 words
a pair of spaced-apart microwave energy conductors located within said transmission line member and having terminal end portions spaced inwardly from said one open end of said transmission line member,
Claim 5
Dependent Claim
30 words
a pair of spaced-apart microwave energy conductors located within said transmission line member and having terminal end portions spaced inwardly from said one open end of said transmission line member,
Claim 6
Dependent Claim
17 words
a second set of parallel conducting rods in spaced relation and interleaved alternately with the first set,
Claim 7
Dependent Claim
17 words
a second set of parallel conducting rods in spaced relation and interleaved alternately with the first set,
Claim 8
Dependent Claim
23 words
a first strap-bar in the form of an exTended conducting plate making contact with each of the first set of parallel conducting rods,
Claim 9
Dependent Claim
23 words
a first strap-bar in the form of an exTended conducting plate making contact with each of the first set of parallel conducting rods,
Claim 10
Dependent Claim
43 words
a pair of transmission members extending into said one open end of said transmission line member and each one of said pair of transmission members being connected at one of their ends thereof to a respective one of said pair of spaced-apart conductors,
Claim 11
Dependent Claim
43 words
a pair of transmission members extending into said one open end of said transmission line member and each one of said pair of transmission members being connected at one of their ends thereof to a respective one of said pair of spaced-apart conductors,
Claim 12
Dependent Claim
19 words
An apparatus, as defined in claim 1, said apparatus including means for measuring forward, reflected and transmitted microwave power.
Claim 13
Dependent Claim
34 words
An apparatus, as defined in claim 1, said apparatus including a transparent microwave radiation shield adapted for unobstructed observation of a plasma, said radiation shield surrounding said slow wave structure and said plasma container.
Claim 14
Dependent Claim
41 words
each of said conductors being tapered inwardly from one of their ends to the other of their ends which are spaced inwardly from said one open end of said transmission line member and which ends are connected to said transmission members,
Claim 15
Dependent Claim
41 words
each of said conductors being tapered inwardly from one of their ends to the other of their ends which are spaced inwardly from said one open end of said transmission line member and which ends are connected to said transmission members,
Claim 16
Dependent Claim
78 words
a second strap-bar generally parallel to the first strap-bar and in the form of an extended conducting plate making contact with each of the second set of parallel conducting rods, c. and microwave energization means operatively attached to said first and second strap-bars of said microwave structure adapted to energize said microwave structure so that a region adjacent said structure will contain a predominance of degenerate pi /2 mode or near degenerate pi /2 mode electric field energy.
Claim 17
Dependent Claim
78 words
a second strap-bar generally parallel to the first strap-bar and in the form of an extended conducting plate making contact with each of the second set of parallel conducting rods, c. and microwave energization means operatively attached to said first and second strap-bars of said microwave structure adapted to energize said microwave structure so that a region adjacent said structure will contain a predominance of degenerate pi /2 mode or near degenerate pi /2 mode electric field energy.
Claim 18
Dependent Claim
79 words
strapped bar conductive means operatively connected to each of said transmission members at the other ends thereof, b. and microwave energy generating means operatively connected to said slow wave microwave structure for applying microwave energy to said slow wave structure, said energy generating means applying energy of such frequency and said conductors being constructed to generate a region adjacent said structure which will contain a predominance of degenerate pi /2 of near degenerate pi /2 mode electric field energy.
Claim 19
Dependent Claim
79 words
strapped bar conductive means operatively connected to each of said transmission members at the other ends thereof, b. and microwave energy generating means operatively connected to said slow wave microwave structure for applying microwave energy to said slow wave structure, said energy generating means applying energy of such frequency and said conductors being constructed to generate a region adjacent said structure which will contain a predominance of degenerate pi /2 of near degenerate pi /2 mode electric field energy.
Claim 20
Dependent Claim
19 words
An apparatus, as defined in claim 1, wherein said slow wave structure is a non-resonant semi-radiant strapped bar type.
Claim 21
Dependent Claim
47 words
An apparatus, as defined in claim 4, wherein said radiation shield comprises an inner wall made of a transparent dielectric material, an outer wall made of a transparent dielectric material, and a transparent liquid which absorbs microwave energy filling the space between said inner and outer walls.
Claim 22
Dependent Claim
148 words
A slow-wave microwave applicator apparatus suitable for use for heating, drying, curing, ionization of gases, or other treatment of workpieces by microwave energy, and which gases or workpieces contain lossy dielectric material, in solid, liquid or gaseous form, said apparatus comprising a slow wave microwave structure, and microwave energization means connected to the said microwave structure adapted to energize said microwave structure so that a region adjacent said structure will contain a predominance of degenerate pi /2 mode or near degenerate pi /2 mode primarily backward wave electric field energy to enable band edge operation at the pi /2 mode, the backward waves of said electric field energy housing, a phase velocity approaching zero and propagating their energy in one direction and their phase fronts in an opposite direction, the operation bandpass of said slow wave structure being defined by a frequency spectrum F1-F0 near the mode bandedge.
Claim 23
Dependent Claim
148 words
A slow-wave microwave applicator apparatus suitable for use for heating, drying, curing, ionization of gases, or other treatment of workpieces by microwave energy, and which gases or workpieces contain lossy dielectric material, in solid, liquid or gaseous form, said apparatus comprising a slow wave microwave structure, and microwave energization means connected to the said microwave structure adapted to energize said microwave structure so that a region adjacent said structure will contain a predominance of degenerate pi /2 mode or near degenerate pi /2 mode primarily backward wave electric field energy to enable band edge operation at the pi /2 mode, the backward waves of said electric field energy housing, a phase velocity approaching zero and propagating their energy in one direction and their phase fronts in an opposite direction, the operation bandpass of said slow wave structure being defined by a frequency spectrum F1-F0 near the mode bandedge.
Claim 24
Dependent Claim
54 words
A slow-wave microwave applicator apparatus suitable for use for heating, drying, curing, ionization of gases, or other treatment of workpieces by microwave energy, and which gases or workpieces contain lossy dielectric material, in solid, liquid or gaseous form, said apparatus comprising: a. a slow wave microwave structure, b. said slow wave microwave structure comprising:
Claim 25
Dependent Claim
54 words
A slow-wave microwave applicator apparatus suitable for use for heating, drying, curing, ionization of gases, or other treatment of workpieces by microwave energy, and which gases or workpieces contain lossy dielectric material, in solid, liquid or gaseous form, said apparatus comprising: a. a slow wave microwave structure, b. said slow wave microwave structure comprising:
Claim 26
Dependent Claim
37 words
An apparatus, as defined in claim 1, wherein said source of microwave energy is designed so that said apparatus is capable of providing radiation in the wave length ranging from the vacuum ultraviolet to the far infared.
Claim 27
Dependent Claim
88 words
An apparatus for generating a plasma as defined in Claim 1, wherein said apparatus includes a transparent microwave radiation shield surrounding said slow wave structure and said plasma container and being adapted to provide an unobstructed observation of a plasma generated from said ionizable gaseous fluid, said radiation shield comprising: a. an inner wall made of a transparent dielectric material, b. an outer wall made of a transparent dielectric material, c. and a transparent liquid which absorbs microwave energy filling the space between said inner and outer walls.
Claim 28
Independent Claim
239 words
An apparatus for generating a plasma using electromagnetic energy in the microwave frequency range comprising a source of microwave energy, at least one slow wave structure having an input end for receiving microwave energy from the source thereof and forming a region adjacent to said slow wave structure which contains a predominance of degenerate pi /2 or near-degenerate pi /2 mode primarily backward wave electromagnetic energy to enable band edge operation at the pi /2 mode, the backward waves of said electromagnetic field energy housing a phase velocity approaching zero and propagating their energy in one direction and their phase fronts in the opposite direction, the operation bandpass of said slow wave structure being defined by a frequency spectrum F1-F0 near the pi /2 mode bandedge, said electromagnetic energy having a normal attenuation constant Beta n, and said slow wave structure having a longitudinal attenuation constant Beta L, and the electromagnetic wave inside of the plasma container having a linear attenuation constant Beta g which are relatively constant, such that the electric field vector of the backward wave electromagnetic energy is relatively constant, means for conveying said microwave energy from said source of said microwave energy to the input end of said slow wave structure, a plasma container located with respect to said region and adapted to contain a ionizable gaseous fluid for receiving and applying said microwave energy to said ionizable gaseous fluid to generate a plasma therefrom.
Claim 29
Independent Claim
239 words
An apparatus for generating a plasma using electromagnetic energy in the microwave frequency range comprising a source of microwave energy, at least one slow wave structure having an input end for receiving microwave energy from the source thereof and forming a region adjacent to said slow wave structure which contains a predominance of degenerate pi /2 or near-degenerate pi /2 mode primarily backward wave electromagnetic energy to enable band edge operation at the pi /2 mode, the backward waves of said electromagnetic field energy housing a phase velocity approaching zero and propagating their energy in one direction and their phase fronts in the opposite direction, the operation bandpass of said slow wave structure being defined by a frequency spectrum F1-F0 near the pi /2 mode bandedge, said electromagnetic energy having a normal attenuation constant Beta n, and said slow wave structure having a longitudinal attenuation constant Beta L, and the electromagnetic wave inside of the plasma container having a linear attenuation constant Beta g which are relatively constant, such that the electric field vector of the backward wave electromagnetic energy is relatively constant, means for conveying said microwave energy from said source of said microwave energy to the input end of said slow wave structure, a plasma container located with respect to said region and adapted to contain a ionizable gaseous fluid for receiving and applying said microwave energy to said ionizable gaseous fluid to generate a plasma therefrom.
Claim 30
Dependent Claim
28 words
An apparatus, as defined in claim 11, wherein said source of microwave energy has a frequency in the range of from about 100 MHz to about 30,000 MHz.
Claim 31
Dependent Claim
28 words
An apparatus, as defined in claim 11, wherein said source of microwave energy has a frequency in the range of from about 915 MHz to about 5,800 MHz.
Claim 32
Dependent Claim
19 words
An apparatus, as defined in claim 11, wherein said slow wave structure is a non-resonant, semi-radiant strapped bar type.
Claim 33
Independent Claim
146 words
An apparatus for generating a plasma using electromagnetic energy in the microwave frequency range, said apparatus comprising a plasma container capable of having an ionizable gaseous fluid introducible thereinto, said container being formed with a wall capable of permitting microwave energy to be coupled into the gaseous fluid, at least one slow wave structure having an input end for applying microwave energy to said ionizable gaseous fluid to generate a plasma therefrom, means for conveying said microwave eneRgy from said microwave energy generating means to the input end of said slow wave structure, the longitudinal axis of said plasma container being angularly located with respect to the longitudinal axis of said slow wave structure at an angle theta so that electromagnetic waves propagating along the length of said slow wave structure will provide a relatively constant energy transfer profile along the length of the plasma container.
Claim 34
Independent Claim
146 words
An apparatus for generating a plasma using electromagnetic energy in the microwave frequency range, said apparatus comprising a plasma container capable of having an ionizable gaseous fluid introducible thereinto, said container being formed with a wall capable of permitting microwave energy to be coupled into the gaseous fluid, at least one slow wave structure having an input end for applying microwave energy to said ionizable gaseous fluid to generate a plasma therefrom, means for conveying said microwave eneRgy from said microwave energy generating means to the input end of said slow wave structure, the longitudinal axis of said plasma container being angularly located with respect to the longitudinal axis of said slow wave structure at an angle theta so that electromagnetic waves propagating along the length of said slow wave structure will provide a relatively constant energy transfer profile along the length of the plasma container.
Claim 35
Dependent Claim
18 words
An apparatus, as defined in claim 15, wherein said angle theta is between about 1* to about 30*.
Claim 36
Dependent Claim
62 words
An apparatus, as defined in claim 15, wherein the angle theta is established to obtain a constant energy density transfer through the plasma container based on the normal attenuation constant of the electric field strength which produces the electromagnetic energy, the longitudinal attenuation constant of the slow wave structure, and the linear attenuation constant of the electromagnetic waves in the plasma container.
Claim 37
Dependent Claim
67 words
An apparatus, as defined in claim 15, wherein the angle theta is established to obtain a constant energy density transfer through the plasma container based on the ratio of the normal attenuation constant of the electric field strength, which produces the electromagnetic energy, divided by the longitudinal attenuation constant of the slow wave structure, plus the linear attenuation constant of the electromagnetic waves in the plasma container.
Claim 38
Dependent Claim
21 words
An apparatus, as defined in claim 15, wherein said slow wave structure is a non-resonant, semi-radiant strapped bar type of structure.
Claim 39
Dependent Claim
53 words
An apparatus, as defined in claim 15, wherein said slow wave structure is a wide-band, semi-radiant strapped bar type of structure, and said apparatus is adapted to be operated so that the region adjacent to said slow wave structure contains a predominance of degenerate pi /2, or near-degenerate pi /2 mode electromagnetic energy.
Claim 40
Independent Claim
209 words
An apparatus for generating a plasma using electromagnetic energy in the microwave frequency range, said apparatus comprising a plasma container capable of having an ionizable gaseous fluid introducible thereinto, said container being formed of a wall relatively transparent to microwave energy and capable of permitting microwave energy to be coupled into the gaseous fluid, microwave energy generating means for generating a source of microwave energy, a transmission line adapted to transmit microwave energy and being operatively connected to said microwave energy generating means for receiving and transmitting the microwave energy thus generated, tuning means operatively connected to said transmission line to obtain minimum energy-return reflection to said generating means, a slow wave structure having an input end for applying microwave energy to an ionizable gaseous fluid in said plasma container to generate a plasma therefrom, transition means operatively connected to said tuning means and said input end of said slow wave structure for delivering the microwave energy to said slow wave structure, said plasma container being located proximate to said slow wave structure to receive the microwave energy carried by said slow wave structure, means for providing a source of ionizable gaseous fluid to the plasma container, and means operatively interposed between said last-named means and said plasma container.
Claim 41
Independent Claim
209 words
An apparatus for generating a plasma using electromagnetic energy in the microwave frequency range, said apparatus comprising a plasma container capable of having an ionizable gaseous fluid introducible thereinto, said container being formed of a wall relatively transparent to microwave energy and capable of permitting microwave energy to be coupled into the gaseous fluid, microwave energy generating means for generating a source of microwave energy, a transmission line adapted to transmit microwave energy and being operatively connected to said microwave energy generating means for receiving and transmitting the microwave energy thus generated, tuning means operatively connected to said transmission line to obtain minimum energy-return reflection to said generating means, a slow wave structure having an input end for applying microwave energy to an ionizable gaseous fluid in said plasma container to generate a plasma therefrom, transition means operatively connected to said tuning means and said input end of said slow wave structure for delivering the microwave energy to said slow wave structure, said plasma container being located proximate to said slow wave structure to receive the microwave energy carried by said slow wave structure, means for providing a source of ionizable gaseous fluid to the plasma container, and means operatively interposed between said last-named means and said plasma container.
Claim 42
Dependent Claim
24 words
An apparatus, as defined in claim 21, said apparatus comprising a dummy load operatively connected to an output end of said slow wave structure.
Claim 43
Dependent Claim
20 words
An apparatus, as defined in claim 21, said apparatus comprising monitoring means for measuring forward, reflected and transmitted microwave power.
Claim 44
Dependent Claim
53 words
A slow-mode microwave applicator suitable for heating, drying, curing, ionization of gases, or other treatment by microwave energy of workpieces containing lossy dielectric material, and which dielectric material may be in solid, liquid or gaseous form, said microwave applicator comprising: a. a slow wave microwave structure, and said slow wave microwaVe structure comprising:
Claim 45
Dependent Claim
53 words
A slow-mode microwave applicator suitable for heating, drying, curing, ionization of gases, or other treatment by microwave energy of workpieces containing lossy dielectric material, and which dielectric material may be in solid, liquid or gaseous form, said microwave applicator comprising: a. a slow wave microwave structure, and said slow wave microwaVe structure comprising:
Claim 46
Dependent Claim
115 words
A slow-mode microwave applicator, as defined in claim 24, wherein said strapped bar conductive means comprises: a. a first set of parallel conducting rods in spaced relation, b. a second set of parallel conducting rods in spaced relation and interleaved alternately with the first set, c. a first strap-bar in the form of an extended conducting plate making contact with each of the first set of parallel conducting rods and one of said transmission members, and d. a second strap-bar generally parallel to the first strap bar and in the form of an extended conducting plate making contact with each of the second set of parallel conducting rods and the other of said transmission members.
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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) | 1977-06-03 | 1977-12-03 | 1978-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-03 | 1981-12-03 | 1982-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-03 | 1985-12-03 | 1986-06-04 | $7700.00 | Window Closed / Lapsed |