Patent US3556640A successfully refreshed from Google Patents.
US3556640A
Expired / Lapsed
US
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Interference filter with dielectric tuning layers
Assignee: Applied Biosystems Inc
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Filing: 1968-03-01
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Granted: 1971-01-19
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Expires: 1988-03-01
Abstract
Abstract A THREE REFLECTOR INTERFERENCE FILTER IN WHICH THE TWO SPACER ELEMENTS USED TO SEPARATE THE REFLECTORS ARE MADE OF SOLID GLASS. THE TWO OUTER REFLECTORS ARE MULTILAYER DIELECTRIC FILMS AND ARE FORMED ON SEPARATE SUBSTRATES. THE OUTER ENDS OF THE TWO SPACER ELEMENTS ARE OPTICALLY CONTACTED TO THE SUBSTRATES. THE INNER ENDS OF THE SPACER ELE- MENTS ARE OPTICALLY CONTACTED TO EACH OTHER. THE INNER REFLECTOR, WHICH IS A METAL FILM IS FORMED ON THE INNER END OF ONE OF THE SPACERS.
Inventors
- 👤 Robert R Austin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:42
CPC Classifications
G; G02; G02B; G02B5/00; G02B5/20; G02B5/28; G02B5/285; G02B5/288
Claims Analysis
Total Claims: 0
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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) | 1974-01-18 | 1974-07-20 | 1975-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-18 | 1978-07-20 | 1979-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-18 | 1982-07-20 | 1983-01-19 | $7700.00 | Window Closed / Lapsed |