US3606542A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Complex-valued spatial filter using phase modulation only
Assignee: International Business Machines Corp
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Filing: 1970-01-19
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Granted: 1971-09-20
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Expires: 1990-01-19
Abstract
Abstract AN IMPROVED OPTICAL SPATIAL FILTER TO PRODUCE A TRANSFORM (IMAGE) REPRESENTING PHASE AND AMPLITUDE MODULATION OF THE INCIDENT WAVE. THE FILTER IS NON-ABSORPTIVE AND ACHIEVES AMPLITUDE MODULATION OF THE DESIRED IMAGE IN A SELECTED DIFFRACTION ORDER BY DIFFRACTING THE UNWANTED LIGHT INTO NON-SELECTED ORDERS. THE FILTER IS FABRICATED USING ONLY PHASE FILTER TECHNIQUES. OTHER APPLICATION FOR THE FILTER INCLUDE CONVERSION OF A WAVE EMANATING FROM A GIVEN OBJECT INTO A WAVE REPRESENTING A GIVEN IMAGE. EITHER A TRANSMITTED OR REFLECTED WAVE CAN BE USED TO CONSTRUCT THE IMAGE.
Inventors
- 👤 Joseph P Kirk
- 👤 Andrew J Lavin
- 👤 William C Rodgers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 04:18
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/42; G02B27/46; H; H03; H03M; H03M7/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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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) | 1974-09-19 | 1975-03-21 | 1975-09-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-19 | 1979-03-21 | 1979-09-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-19 | 1983-03-21 | 1983-09-20 | $7700.00 | Window Closed / Lapsed |