US2427689A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microscope with special light modifiers
Assignee: American Optical Corp
•
Filing: 1942-08-28
•
Granted: 1947-09-23
•
Expires: 1962-08-28
Abstract
No abstract record available.
Inventors
- 👤 Osterberg Harold
- 👤 Henry S Schrader
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 18:49
CPC Classifications
G; G02; G02B; G02B21/00; G02B21/06; G02B21/08; G02B21/14
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
USRE22076E
Cited
US561132A
Cited
US513912A
Cited
GB190712512A
Cited
US905633A
Cited
CH98827A
Cited
CH100631A
Cited
US1784425A
Cited
US1724425A
Cited
US1860430A
Cited
DE636168C
Cited
US2079621A
Cited
US2265182A
Cited
US2205179A
Cited
US2237943A
Cited
US2264835A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1950-09-22 | 1951-03-24 | 1951-09-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1954-09-22 | 1955-03-24 | 1955-09-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1958-09-22 | 1959-03-24 | 1959-09-23 | $7700.00 | Window Closed / Lapsed |