Patent US4934818A successfully refreshed from Google Patents.
US4934818A
Expired / Lapsed
US
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Refractive index profiling technique
Assignee: Furukawa Electric North America Inc
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Filing: 1989-03-24
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Granted: 1990-06-19
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Expires: 2009-03-24
Abstract
Abstract A monochromatic light beam scans a silica reference and a translucent body, both submerged in index matching fluid and the deflection angle of the beam is measured as it exits the reference, the translucent body and the fluid. This deflection angle of the light beam exiting the reference is compared with the undeflected beam passing through only the fluid. The difference, if any, is used to offset the measurements of the deflection angles of the light beam exiting the translucent body to correct them so that the profile is referenced to the index of silica.
Inventors
- 👤 Werner J. Glantschnig
- 👤 Knut D. Pohl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-10 02:01
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/41; G01N21/412; G01N21/01; G01N21/03; G01N2021/0342
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
74 words
A method of nondestructively determining the refractive index of a translucent body, comprising the steps of: scanning a light beam across at least a portion of the surfaces of the translucent body and a translucent reference; detecting the refraction angles of the light beams exiting both the translucent body and the reference; and comparing the detected refraction angle data thereby determining the refractive index profile of the translucent body relative to the translucent reference.
Claim 2
Independent Claim
74 words
A method of nondestructively determining the refractive index of a translucent body, comprising the steps of: scanning a light beam across at least a portion of the surfaces of the translucent body and a translucent reference; detecting the refraction angles of the light beams exiting both the translucent body and the reference; and comparing the detected refraction angle data thereby determining the refractive index profile of the translucent body relative to the translucent reference.
Claim 3
Dependent Claim
14 words
The method of claim 1 in which the transparent body is an unclad preform.
Claim 4
Dependent Claim
14 words
The method of claim 1 in which the transparent body is an unclad tube.
Claim 5
Dependent Claim
32 words
The method of claim 1 in which the light beam is a narrow beam of monochromatic light scanned substantially perpendicular to an imaginary plane containing the longitudinal axis of the translucent body.
Claim 6
Dependent Claim
49 words
The method of claim 1 in which the translucent body and the translucent reference are immersed in index matching fluid and further includes the step of preprocessing the detected refraction angle data to correct the data for effects arising from an index mismatch between the fluid and the reference.
Claim 7
Dependent Claim
14 words
The method of claim 1 in which the reference is a silica angle prism.
Claim 8
Dependent Claim
38 words
The method of claim 1 in which the reference is a silica rod mounted with its longitudinal axis in a plane containing the longitudinal axis of the translucent body, which plane is substantially perpendicular to the light beam.
Claim 9
Dependent Claim
76 words
Apparatus for nondestructively determining the refractive index of a translucent body, comprising: means for scanning a light beam across at least a portion of the surfaces of the translucent body and a translucent reference, means for detecting the refraction angles of the scanning beam exiting both the translucent body and the reference; and means for comparing the detected refraction angle data thereby determining the refractive index profile of the translucent body relative to the translucent reference.
Claim 10
Dependent Claim
76 words
Apparatus for nondestructively determining the refractive index of a translucent body, comprising: means for scanning a light beam across at least a portion of the surfaces of the translucent body and a translucent reference, means for detecting the refraction angles of the scanning beam exiting both the translucent body and the reference; and means for comparing the detected refraction angle data thereby determining the refractive index profile of the translucent body relative to the translucent reference.
Claim 11
Dependent Claim
14 words
The apparatus of claim 8 in which the translucent body is an unclad preform.
Claim 12
Dependent Claim
14 words
The apparatus of claim 8 in which the translucent body is an unclad tube.
Claim 13
Dependent Claim
33 words
The apparatus of claim 8 in which the light beam is a narrow beam of monochromatic light scanned in a plane perpendicular to a plane containing the longitudinal axis of the translucent body.
Claim 14
Dependent Claim
44 words
The apparatus of claim 8 which includes: means for immersing both objects in index matching fluid; and means for preprocessing the detected angle data to correct for the effects arising from an index mismatch between the refractive indexes of the fluid and the reference.
Claim 15
Dependent Claim
14 words
The apparatus of claim 8 in which the reference is a silica angle prism.
Claim 16
Dependent Claim
39 words
The apparatus of claim 8 in which the reference is a silica rod mounted with its longitudinal axis in a plane containing the longitudinal axis of the translucent body, which plane is substantially perpendicular to the scanning light beam.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-06-18 | 1993-12-18 | 1994-06-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-06-18 | 1997-12-18 | 1998-06-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-06-18 | 2001-12-18 | 2002-06-19 | $7700.00 | Window Closed / Lapsed |