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Title: Fiber optic moisture sensor with moisture-absorbing reflective target

A method and apparatus for sensing moisture changes by utilizing optical fiber technology. One embodiment uses a reflective target at the end of an optical fiber. The reflectance of the target varies with its moisture content and can be detected by a remote unit at the opposite end of the fiber. A second embodiment utilizes changes in light loss along the fiber length. This can be attributed to changes in reflectance of cladding material as a function of its moisture content. It can also be affected by holes or inserts interposed in the cladding material and/or fiber. Changing light levels can also be coupled from one fiber to another in an assembly of fibers as a function of varying moisture content in their overlapping lengths of cladding material.
  1. (Richland, WA)
Publication Date:
OSTI Identifier:
Report Number(s):
US 4634856
DOE Contract Number:
Resource Type:
Research Org:
Country of Publication:
United States
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