US3799654A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical interference filter having an intermediate energy absorbing layer
Assignee: Pfizer Health AB
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Filing: 1972-02-17
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Granted: 1974-03-26
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Expires: 1992-02-17
Abstract
Abstract An optical interference filter, comprising two parallel transmitting and reflecting surfaces arranged at a distance from each other, which is a multiple of half the transmitted wavelength, at least one energy absorbing layer being located between the surfaces at a distance from the surfaces which is a multiple of half the transmitted wavelength.
Inventors
- 👤 W Donne
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 21:05
CPC Classifications
G; G02; G02B; G02B5/00; G02B5/20; G02B5/28; G02B5/284
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
61 words
An optical interference filter, comprising two parallel partially reflecting surfaces arranged at a distance from each other, which is a multiple of half the transmitted wavelength, characterized in, that at least one predominantly energy absorbing layer is located between, and parallel to, the partially reflecting surfaces at a distance from each surface which is a multiple of half the transmitted wavelength.
Claim 2
Dependent Claim
61 words
An optical interference filter, comprising two parallel partially reflecting surfaces arranged at a distance from each other, which is a multiple of half the transmitted wavelength, characterized in, that at least one predominantly energy absorbing layer is located between, and parallel to, the partially reflecting surfaces at a distance from each surface which is a multiple of half the transmitted wavelength.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-03-25 | 1977-09-24 | 1978-03-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-25 | 1981-09-24 | 1982-03-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-25 | 1985-09-24 | 1986-03-26 | $7700.00 | Window Closed / Lapsed |