US3784928A
Expired / Lapsed
US
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Gas discharge device and electrode for use therein
Assignee: RCA Inc
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Filing: 1971-06-04
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Granted: 1974-01-08
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Expires: 1991-06-04
Abstract
Abstract A carbon dioxide laser having a dense ceramic casing of high thermal conductivity which is non-reactive with the gas mixture. The anode and cathode electrodes of the laser comprise a rhodiumplatinum alloy, which exhibits a low sputtering rate and which is also non-reactive with the gas mixture. The resulting device exhibits a lifetime of 8,000 hours or more under sealed conditions.
Inventors
- 👤 R Crane
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 21:29
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/02; H01S3/03; H01S3/038; H01S3/0388; H01S3/0305; H01S3/14; H01S3/22; H01S3/223; H01S3/2232
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
66 words
The gas discharge device defined in claim 1, wherein said gas mixture comprises, by volume, on the order or 14 percent carbon dioxide, 22 percent nitrogen, 64 percent helium, and either (i) xenon to a partial pressure of 1 to 2 torr or (ii) water vapor to a partial pressure of 0.1 to 0.7 torr, the total gas pressure being on the order of 20 torr.
Claim 2
Dependent Claim
24 words
The gas discharge device defined in claim 1, wherein said cathode electrode comprises a platinum-rhodium alloy containing at least 1 percent rhodium by weight.
Claim 3
Dependent Claim
17 words
The gas discharge device defined in claim 3, wherein said alloy contains 10 percent rhodium by weight.
Claim 4
Dependent Claim
15 words
The gas discharge device defined in claim 4, wherein said cathode electrode is generally cylindrical.
Claim 5
Dependent Claim
46 words
The gas discharge device defined in claim 1, wherein said envelope comprises a thermally conductive ceramic material having a porosity to helium in the order of 10 12 std/cc/cm2 or less, said ceramic material being substantially non-reactive with said gas mixture and with decomposition products thereof.
Claim 6
Dependent Claim
29 words
The gas discharge device defined in claim 4, wherein said ceramic material comprises alumina, thallia, beryllia, zirconia, lithium aluminum silicate, silicon carbide, boron carbide, calcium fluoride or magnesium fluoride.
Claim 7
Dependent Claim
66 words
The gas discharge device defined in claim 7, wherein said gas mixture comprises, by volume, on the order of 14 percent carbon dioxide, 22 percent nitrogen, 64 percent helium, and either (i) xenon to a partial pressure of 1 to 2 torr or (ii) water vapor to a partial pressure of 0.1 to 0.7 torr, the total gas pressure being on the order of 20 torr.
Claim 8
Dependent Claim
24 words
The gas discharge device defined in claim 7, wherein said cathode electrode comprises a platinum-rhodium alloy containing at least 1 percent rhodium by weight.
Claim 9
Dependent Claim
17 words
The gas discharge device defined in claim 9, wherein said alloy contains 10 percent rhodium by weight.
Claim 10
Dependent Claim
15 words
The gas discharge device defined in claim 10, wherein said cathode electrode is generally cylindrical.
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) | 1977-01-07 | 1977-07-09 | 1978-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-07 | 1981-07-09 | 1982-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-07 | 1985-07-09 | 1986-01-08 | $7700.00 | Window Closed / Lapsed |