Intrinsic fiber–optic ultrasonic sensor array using multiplexed two–wave mixing interferometry

Pavel Fomitchov, Todd W. Murray, Sridhar Krishnaswamy

Research output: Contribution to journalArticlepeer-review

30 Scopus citations


An intrinsic multiplexed laser interferometer is presented that allows for the simultaneous detection of acoustic waves by an array of fiber-optic sensors. The phase-modulated signals from each sensor are demodulated by use of an adaptive two–wave mixing setup. The light from each sensing fiber in the array is mixed with a reference beam in a single photorefractive crystal (PRC), and the output beams from the PRC are imaged onto separate photodetectors to create a multiplexed two–wave mixing (MTWM) system. The sensing fibers are embedded in graphite–epoxy composite panels, and detection of both acoustic emission and ultrasonic signals in these materials is demonstrated. The intrinsic MTWM system is an effective tool for the simultaneous demodulation of signals from a large fiber sensor array. Also, the adaptive nature of the MTWM setup obviates the need for active stabilization against ambient noise.

Original languageEnglish (US)
Pages (from-to)1262-1266
Number of pages5
JournalApplied optics
Issue number7
StatePublished - Mar 1 2002

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics
  • Engineering (miscellaneous)
  • Electrical and Electronic Engineering


Dive into the research topics of 'Intrinsic fiber–optic ultrasonic sensor array using multiplexed two–wave mixing interferometry'. Together they form a unique fingerprint.

Cite this