Distributed acoustic defect detection system utilizing optical interferometers
AssigneePure Technologies U.S. Inc.
InventorsJohn Allison McIntyre, Marshall Glen Kennedy
Life of this patent
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Abstract
A distributed acoustic sensing system can include an optical interferometer. The optical interferometer can include an optical fiber coupler to split optical light signals, and an optical fiber delay coil to introduce a controlled time delay in one of the paths. At least one path can form a loop, enabling controlled delay and temporary storage of light, resulting in interference patterns. The system can progressively mitigate noise or distortion, improving sensitivity and/or signal reception quality for defect detection.
Claims20
An optical interferometer comprising:
- an optical coupler configured to combine first light signals traversing a first path and second light signals traversing a second path to form combined light signals, the optical coupler further configured to separate the combined light signals into at least the second path and a third path,
- wherein the first light signals correspond to optical light signals that are indicative of acoustic disturbances across a distributed acoustic sensing system, and wherein the second path is a feedback loop;
- and
- an optical fiber delay coil arranged along the second path and configured to introduce a controlled time delay in the second light signals traversing the second path,
- wherein a signal acquisition and processing system determines characteristics of the acoustic disturbances based at least in part on third light signals traversing the third path.
A distributed acoustic sensing system, comprising:
- a sensing optical fiber configured to transmit first light signals along a first path, the sensing optical fiber positioned proximate to a structure such that the first light signals are modulated by acoustic disturbances corresponding to at least one of structural defects or environmental changes in the structure;
- and
- an optical interferometer, comprising:
- an optical coupler configured to receive the first light signals and combine first light signals traversing the first path and second light signals traversing a second path to form combined light signals, the optical coupler further configured to separate the combined light signals into at least the second path and a third path, wherein the second path is a feedback loop;
- and
- an optical fiber delay coil arranged along the second path and configured to introduce a controlled time delay in the second light signals traversing the second path.
- wherein a signal acquisition and processing system determines characteristics of the acoustic disturbances based at least in part on third light signals traversing the third path.
A method for detecting acoustic disturbances using an optical interferometer, comprising:
- splitting first light signals indicative of acoustic disturbances into a first path and a second path using an optical coupler, wherein the first light signals traverse the first path and the second path;
- introducing a controlled time delay in second light signals traversing the second path using an optical fiber delay coil arranged along the second path;
- combining the first light signals and the time-delayed second light signals to form combined light signals using the optical coupler;
- and
- separating the combined light signals into at least the second path and a third path using the optical coupler, wherein the second path forms a feedback loop for subsequent signals and the third path provides output signals;
- wherein a signal acquisition and processing system determines characteristics of the acoustic disturbances based at least in part on the light signals traversing the third path.
Dependencies are inferred from the claim text.