Patent US2647441A successfully refreshed from Google Patents.
US2647441A
Expired / Lapsed
US
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Front surface mirror improved by transparent protective overcoating
Assignee: Individual
•
Filing: 1945-04-27
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Granted: 1953-08-04
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Expires: 1965-04-27
Abstract
No abstract record available.
Inventors
- 👤 Raymond W Boydston
- 👤 Allen J Eshner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 21:47
CPC Classifications
C; C03; C03C; C03C17/00; C03C17/34; C03C17/36; C03C17/3602; C03C17/3605; C03C17/3621; C03C17/3642; C03C17/3657; C03C17/3663; G02B1/105; G; G02; G02B; G02B1/00; G02B1/10; G02B1/14; C03C2217/00; C03C2217/70; C03C2217/78
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
91 words
IN A MIRROR, A BLANK OF BASE MATERIAL, A FOLM OF REFLECTING METAL CARRIED BY THE FRONT SURFACE OF SAID BLANK, AND A TOUGH AND DURABLE TRANSPARENT PROTECTIVE COATING OF MAGNESIUM FLUORIDE COVERING THE SURFACE OF SAID REFLECTING FILM IN THICKNESS SUBSTANTIALLY ONE HALF OR AN EXACT MULTIPLE OF ONE HALF A SELECTED WAVE LENGTH OF THE LIGHT WHICH THE MIRROR IS TO REFLECT AND SERVING TO REFLECT VISIBLE RAYS THEREOF IN PHASE WITH THOSE REFLECTED BY THE UNDERLYING METAL FILM WHEREBY TO ADD TO THE MIRROR''S TOTAL LIGHT REFLECTING EFFICIENTY.
References Cited (Backward Citations)
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US2220861A
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US2281474A
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US2366516A
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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) | 1956-08-03 | 1957-02-02 | 1957-08-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-08-03 | 1961-02-02 | 1961-08-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-08-03 | 1965-02-02 | 1965-08-04 | $7700.00 | Window Closed / Lapsed |