US4488813A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reflectivity compensating system for fiber optic sensor employing dual probes at a fixed gap differential
Assignee: Soluna Holdings Inc
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Filing: 1982-04-29
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Granted: 1984-12-18
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Expires: 2002-04-29
Abstract
Abstract This invention provides for the use of two similar fiber optic probes set at a fixed position differential relative to each other in order that a calibration correction signal can be obtained which may be used to create a common output signal having a gap calibration which is independent of surface reflectance.
Inventors
- 👤 Curtis Kissinger
- 👤 Richard Dorman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 07:51
CPC Classifications
G; G01; G01B; G01B11/00; G01B11/02; G01B11/026
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
184 words
An optical system for determining the position of a target, said system comprising: a first fiber optic proximity probe at a variable distance X 1 from the target and capable of generating an output E 1 corresponding to the amount of light reflected by the target to the probe over distance X 1 ; a second fiber optic proximity probe at a variable distance X 2 from the target and capable of generating an output E 2 corresponding to the amount of light reflected by the target to the probe over distance X 2 ; said probes are disposed at different distances from the target in such a manner that the difference between said distances is predetermined; and means for determining X 1 in accordance with the following equation: ##EQU3## wherein X 1 is the distance from the first probe to the target, A is the difference in the distance of the two probes from the target, and E 1 and E 2 are both in the linear range of the common response curve for the light reflected by the target to the probes.
Claim 2
Dependent Claim
184 words
An optical system for determining the position of a target, said system comprising: a first fiber optic proximity probe at a variable distance X 1 from the target and capable of generating an output E 1 corresponding to the amount of light reflected by the target to the probe over distance X 1 ; a second fiber optic proximity probe at a variable distance X 2 from the target and capable of generating an output E 2 corresponding to the amount of light reflected by the target to the probe over distance X 2 ; said probes are disposed at different distances from the target in such a manner that the difference between said distances is predetermined; and means for determining X 1 in accordance with the following equation: ##EQU3## wherein X 1 is the distance from the first probe to the target, A is the difference in the distance of the two probes from the target, and E 1 and E 2 are both in the linear range of the common response curve for the light reflected by the target to the probes.
Claim 3
Dependent Claim
52 words
The system in accordance with claim 1 wherein the determining means comprises sample-and-hold circuit means for retaining the outputs E 2 and E 1 of the probes, difference means capable of providing an output E 2 -E 1 ; and ratioing means capable of determining E 1 /(E 2 -E 1 ).
Claim 4
Dependent Claim
65 words
The system in accordance with claim 2, wherein said target is rotating and said determining means further comprises a position detector connected to the rotating target and a control means triggered by the position detector such that the sample-and-hold circuit means for retaining the outputs E 1 and E 2 of the probes are each activated as the target rotates in front of the probes.
Claim 5
Independent Claim
149 words
A method of determining the position of a target, comprising the following steps: generating a first signal E 1 in the linear range of a response curve corresponding to the reflection of light from the target to a first fiber optic proximity probe at a first variable distance X 1 from the target; generating a second signal E 2 in the linear range of the same response curve corresponding to the reflection of light from the target to a second fiber optic proximity probe at a second variable distance X 2 from the target; generating an output which corresponds to the ratio E 1 /(E 2 -E 1 ) and determining the distance X 1 in accordance with the equation: ##EQU4## wherein X 1 is the distance from the first probe to the target, and A is the difference in the distance of the two probes from the target.
Claim 6
Independent Claim
149 words
A method of determining the position of a target, comprising the following steps: generating a first signal E 1 in the linear range of a response curve corresponding to the reflection of light from the target to a first fiber optic proximity probe at a first variable distance X 1 from the target; generating a second signal E 2 in the linear range of the same response curve corresponding to the reflection of light from the target to a second fiber optic proximity probe at a second variable distance X 2 from the target; generating an output which corresponds to the ratio E 1 /(E 2 -E 1 ) and determining the distance X 1 in accordance with the equation: ##EQU4## wherein X 1 is the distance from the first probe to the target, and A is the difference in the distance of the two probes from the target.
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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) | 1987-12-18 | 1988-06-18 | 1988-12-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-12-18 | 1992-06-18 | 1992-12-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-12-18 | 1996-06-18 | 1996-12-18 | $7700.00 | Window Closed / Lapsed |