Fiber optic moisture sensor with moisture-absorbing reflective target

Patent · Thu Jan 01 00:00:00 EST 1987

OSTI ID:866104

Kirkham, Randy R ^[1]

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1. Richland, WA

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.

• Research Organization: Battelle Memorial Institute, Columbus, OH (United States)
• DOE Contract Number: AC06-76RL01830
• Assignee: United States of America as represented by United States (Washington, DC)
• Patent Number(s): US 4634856
• OSTI ID: 866104
• Country of Publication: United States
• Language: English

Related Subjects

fiber
optic
moisture
sensor
moisture-absorbing
reflective
target
method
apparatus
sensing
changes
utilizing
optical
technology
embodiment
reflectance
varies
content
detected
remote
unit
opposite
utilizes
light
loss
length
attributed
cladding
material
function
affected
holes
inserts
interposed
changing
levels
coupled
assembly
fibers
varying
overlapping
lengths
remote unit
embodiment utilizes
moisture content
fiber optic
optical fiber
cladding material
light loss
reflective target
moisture sensor
utilizing optical
light level
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