US3671130A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Interferometer of the center balance type
Assignee: Northrop Grumman Guidance and Electronics Co Inc
•
Filing: 1970-07-10
•
Granted: 1972-06-20
•
Expires: 1990-07-10
Abstract
Abstract AN INTERFEROMETER OF THE CENTER BALANCE TYPE INCORPORATING A SUBSTANTIALLY ISOTROPIC, COHERENT LIGHT SOURCE, A RETROREFLECTOR HAVING A BEAM SPLITTING SURFACE AND A STAGE PLATE COMPRISING A PAIR OF OPPOSED PARALLEL MIRRORS IN THE OPTICAL PATH. THE OPTICAL PATH DIFFERENCE IS PROPORTIONAL TO THE DISTANCE FROM THE OPTICAL FIDUCIAL TO A PLANE EQUIDISTANT FROM THE PARALLEL TO THE MIRRORS OF THE STAGE PLATE, AND IS INVARIANT WITH RESPECT TO OTHER TRANSLATIONS OR ROTATIONS OF THE STAGE PLATE SO LONG AS THE MIRRORS REMAIN IN THE OPTICAL PATH.
Inventors
- 👤 John Kent Bowker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 11:47
CPC Classifications
G; G01; G01B; G01B9/00; G01B9/02; G01B9/02015; G01B9/02017; G01B9/02021; G01B9/02055; G01B9/02056; G01B9/02061
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) | 1975-06-20 | 1975-12-20 | 1976-06-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-20 | 1979-12-20 | 1980-06-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-20 | 1983-12-20 | 1984-06-20 | $7700.00 | Window Closed / Lapsed |