US3666463A
Expired / Lapsed
US
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Assignee: International Business Machines Corp
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Filing: 1970-07-06
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Granted: 1972-05-30
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Expires: 1990-07-06
Abstract
Abstract PATTERNS IN A PLURALITY OF MASKS EACH HAVING OPAQUE AND TRANSPARENT REGIONS ARE COMPARED WITHOUT ALTERING THE PATTERN OF OPAQUE AND TRANSPARENT REGIONS IN THE MASKS. A PHOTOSENSITIVE MEDIUM CAPABLE OF INDICATING A DIFFERENT EXPOSURE CONDITION FOR EACH MASK IS USED FOR THIS PURPOSE. THE MASKS ARE SUPERIMPOSED SEQUENTIALLY OVER THE PHOTOSENSITIVE MEDIUM, AND A DIFFERENT EXPOSURE CONDITION IS USED TO EXPOSE THE PHOTOSENSITIVE MEDIUM THROUGH EACH MASK. A DIFFERENT AMOUNT OF ENERGY OF EXPOSURE MAY BE USED FOR EACH MASK OR A DIFFERENT COLOR OF LIGHT MAY BE USED WITH EACH MASK IF A COLOR SENSITIVE PHOTOSENSITIVE MEDIUM IS EMPLOYED.
Inventors
- 👤 David S Beynnon
- 👤 Bruce D King
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 07:02
CPC Classifications
G; G03; G03F; G03F9/00; G03F7/00; G03F7/70; G03F7/70483; G03F7/70605; G03F7/70616; G03F7/70633; H; H10; H10P; H10P95/00
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) | 1975-05-30 | 1975-11-29 | 1976-05-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-30 | 1979-11-29 | 1980-05-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-30 | 1983-11-29 | 1984-05-30 | $7700.00 | Window Closed / Lapsed |