US3674330A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Achromatic doublet lens for infrared radiation
Assignee: Individual
•
Filing: 1971-01-22
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Granted: 1972-07-04
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Expires: 1991-01-22
Abstract
Abstract THE ACHROMATIC DOUBLET LENS DISCLOSED HEREIN EMPLOYS A PAIR OF OPTICAL ELEMENTS, EACH OF WHICH IS CONSTRUCTED OF A RESPECTIVE INFRARED TRANSPARENT ALKALI HALIDE. BY APPROPRIATELY SELECTING THE TWO ALKALI HALIDE IN ACCORDANCE WITH THE TEACHING OF THE PRESENT INVENTION, THE RESULTING DOUBLET IS CAUSED TO THE SUBSTANTIALLY ACHROMATIC OVER A USEFUL RANGE OF WAVELENGTHS, RATHER THAN JUST AT A PAIR OF PRESELECTED WAVELENGTHS AS WOULD BE THE CASE IF THE TWO INFRARED TRANSPARENT MATERIALS WERE ARBITRARILY SELECTED.
Inventors
- 👤 John D Strong
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 04:58
CPC Classifications
G; G02; G02B; G02B13/00; G02B13/14; G02B13/146
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) | 1975-07-04 | 1976-01-03 | 1976-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-04 | 1980-01-03 | 1980-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-04 | 1984-01-03 | 1984-07-04 | $7700.00 | Window Closed / Lapsed |