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Updated: Mar 8, 2026

Doppler Optical Coherence Tomography of Retinal Circulation
Published on: September 18, 2012
Relative change measurement of physical quantities using dual-wavelength coherent OTDR
Abstract:
We propose the use of alternating pulse wavelengths in a direct-detection coherent optical time domain reflectometry (C-OTDR) setup not only to measure strain and temperature changes but also to determine the correct algebraic sign of the change. The sign information is essential for the intended use in distributed mode shape analysis of civil engineering structures. Correlating relative backscatter signal shifts in the temporal/signal domain allows for measuring with correct magnitude and sign. This novel approach is simulated, experimentally implemented and demonstrated for temperature change measurement at a spatial resolution of 1 m.
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