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US2820918A
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US
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Optical device for therapeutic and other purposes
Assignee: Individual
•
Filing: 1955-10-14
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Granted: 1958-01-21
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Expires: 1975-10-14
Abstract
No abstract record available.
Inventors
- 👤 Aronstein Robert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 03:59
CPC Classifications
F; F21; F21V; F21V9/00; F21V9/06; F21Y; F21Y2103/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
GB474907A
Cited
US2122285A
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US2178436A
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US2333085A
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US2290186A
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US2299720A
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US2382939A
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US2461464A
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US2774903A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-01-20 | 1961-07-22 | 1962-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-01-20 | 1965-07-22 | 1966-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-01-20 | 1969-07-22 | 1970-01-21 | $7700.00 | Window Closed / Lapsed |