Patent US4381448A successfully refreshed from Google Patents.
US4381448A
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Wide angle intensity pickoff
Assignee: United States Department of the Army
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Filing: 1981-08-31
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Granted: 1983-04-26
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Expires: 2001-08-31
Abstract
Abstract A wide angle light intensity pickoff system, having a very fine signal reution of less than a degree, provides a linear range of about ±35 degrees with a total range of ±90 degrees. The pickoff system can be used with any angular measurement system. In a gyro system all of the active circuit components, an offset optical source and a detector, are mounted on the unstabilized housing structure. Only a fiber optic bundle is required on the stabilized gimbal for coupling optical signals to the detector. There is no mechanical contact between the stabilized gimbal and the unstabilized housing structure. This prevents gimbal/housing coupling torques while providing a wide angle pickoff capability.
Inventors
- 👤 Aubrey Rodgers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 12:27
CPC Classifications
G; G01; G01B; G01B11/00; G01B11/26
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
109 words
A wide angle light intensity pickoff comprising: a light source, a light detector, and a light coupling means disposed between said light source and said light detector, said light source being adapted for movement with respect to said coupling means, said coupling means having a light receiving face adjacent to said light source and having a second or output face adjacent to and coaxial with said light detector, said light source being positioned for directing a light beam at an acute angle toward said receiving face for providing a variable light intensity on said face in response to movement of said light source with respect to said receiving face.
Claim 2
Dependent Claim
109 words
A wide angle light intensity pickoff comprising: a light source, a light detector, and a light coupling means disposed between said light source and said light detector, said light source being adapted for movement with respect to said coupling means, said coupling means having a light receiving face adjacent to said light source and having a second or output face adjacent to and coaxial with said light detector, said light source being positioned for directing a light beam at an acute angle toward said receiving face for providing a variable light intensity on said face in response to movement of said light source with respect to said receiving face.
Claim 3
Dependent Claim
62 words
A wide angle light intensity pickoff as set forth in claim 1 wherein said light beam is directed at a variable acute angle toward said receiving face for providing a variable light intensity on said face in response to movement between said light source and said receiving face, and said light detector is fixed in position with respect to said light source.
Claim 4
Dependent Claim
17 words
A wide angle light intensity pickoff as set forth in claim 2 wherein said movement is angular.
Claim 5
Dependent Claim
18 words
A wide angle light intensity pickoff as set forth in claim 3 wherein said angular movement is rotational.
Claim 6
Dependent Claim
48 words
A wide angle light intensity pickoff as set forth in claim 3 wherein said angular movement is variable oscillation between two extremes of an arc around a center axis and having a maximum arc of 180°, said receiving face being a fixed radius offset from the center axis.
Claim 7
Dependent Claim
44 words
A wide angle light intensity pickoff as set forth in claim 5 wherein said light source is physically disposed coaxial with said arc center axis and is positioned for directing a beam of light at an acute angle with respect to said center axis.
Claim 8
Dependent Claim
80 words
A wide angle light intensity pickoff as set forth in claim 6 wherein said light source is located for directing said beam of light at said acute angle so that it does not impinge on said receiving face when the arc is at 0° of oscillation and fully impinges on said receiving face when said arc is at 180° of oscillation for providing a variable intensity output to said detector indicative of the degree of movement of said light source.
Claim 9
Dependent Claim
29 words
A wide angle light intensity pickoff as set forth in claim 7 wherein said coupling means is a fiber optic bundle and said receiving face has a circular surface.
Claim 10
Dependent Claim
72 words
A wide angle light intensity pickoff as set forth in claim 7 wherein said light source is prepositioned so that substantially half of the maximum available light or half-light from said source impinges on said receiving face prior to any movement between said light source and said receiving face for providing a linear output from said light detector in response to oscillation through a portion of said arc for at least ±35°.
Claim 11
Dependent Claim
57 words
A wide angle light intensity pickoff as set forth in claim 9 wherein said receiving face has a square surface for enhancing the area of receiving light incidence on said coupling means for extreme angular positions of said light source beyond ±35° of said arc from said half-light position, and thereby increasing the linear range of operation.
Claim 12
Dependent Claim
53 words
A wide angle light intensity pickoff as set forth in claim 10 and further comprising first and second housings, said second housing being moveably disposed with respect to said first housing; said coupling means being disposed on said first housing and said light source and light detector being disposed on said second housing.
Claim 13
Dependent Claim
51 words
A wide angle light intensity pickoff as set forth in claim 11 wherein said coupling means is a fiber optic bundle and said light source is a light emitting semiconductor device, said first housing is a stable platform moveably supported on said second housing and disposed for said angular movement therebetween.
References Cited (Backward Citations)
US4342908A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-04-25 | 1986-10-25 | 1987-04-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-04-25 | 1990-10-25 | 1991-04-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-04-25 | 1994-10-25 | 1995-04-26 | $7700.00 | Window Closed / Lapsed |