US3588227A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lens system for focusing two spaced objects on the same focal plane
Assignee: Nikon Corp
•
Filing: 1969-04-18
•
Granted: 1971-06-28
•
Expires: 1989-04-18
Abstract
Abstract A LENS SYSTEM IS PROVIDED FOR FOCUSING TWO SPACED OBJECTS ON THE SAME FOCAL PLANE, THE IMAGES OF THE OBJECTS BEING OF EQUAL MAGNIFICATION. THE LENS SYSTEM INCLUDES A POSITIVE FRONT LENS GROUP HAVING A FOCAL LENGTH F AND A POSITIVE REAR LENS GROUP HAVING A FOCAL LENGTH F=F/$X WHERE $X IS THE DISTANCE BETWEEN THE TWO OBJECTS. THE REGION BELOW THE OPTICAL AXIS OF THE REAR LENS GROUP IS OF ZERO REFRACTIVE POWER AND THE DISTANCE BETWEEN THE PRINCIPAL PLANES OF THE TWO LENS GROUPS IS MADE EQUAL TO THE FOCAL LENGTH OF THE FIRST LENS GROUP. THE LENS SYSTEM MAY BE USED EITHER WITH DIRECT OR REFLECTED TYPES OF ILLUMINATION.
Inventors
- 👤 Tadaaki Yamamoto
- 👤 Hiroshi Takenaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 02:13
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/10; G02B27/1066; G02B27/12; G02B27/123
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1974-06-27 | 1974-12-27 | 1975-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-27 | 1978-12-27 | 1979-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-27 | 1982-12-27 | 1983-06-28 | $7700.00 | Window Closed / Lapsed |