Patent US2823577A successfully refreshed from Google Patents.
US2823577A
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Multiple slit spectrograph for direct reading spectrographic analysis
Assignee: Leeds and Northrup Co
•
Filing: 1951-08-10
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Granted: 1958-02-18
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Expires: 1971-08-10
Abstract
No abstract record available.
Inventors
- 👤 Raymond C Machler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 21:02
CPC Classifications
G; G01; G01J; G01J3/00; G01J3/02; G01J3/04; G01J3/28; G01J3/30; G01J3/32
Claims Analysis
Total Claims: 0
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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) | 1961-02-17 | 1961-08-19 | 1962-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-02-17 | 1965-08-19 | 1966-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-02-17 | 1969-08-19 | 1970-02-18 | $7700.00 | Window Closed / Lapsed |