Accession Number : ADD011938

Title :   Microbending Fiber Optic Acoustic Sensor.

Descriptive Note : Patent,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Lagakos,N ; Trott,W J

Report Date : 16 Jul 1985

Pagination or Media Count : 15

Abstract : A microbending fiber optic acoustic sensor. A point hydrophone according to a first preferred embodiment of the present Invention includes two opposed pistons which are subjected to an acoustic pressure wave. In response to the pressure wave, the opposed pistons push a pair of deformer plates against an optical fiber to deform the fiber thereby intensity modulating an optical signal passing through the fiber. An extended hydrophone according to a second preferred embodiment of the present Invention includes an optical fiber wound in a helical groove formed in a cylindrical surface. A plurality of parallel axial slots are located in a spaced-apart relationship to each other at positions about the cylindrical surface and are oriented in parallel with the axis of the cylindrical surface. Each axial slot intersects with the helical groove at a plurality of locations and has a depth greater than the depth of the groove. An applied acoustic pressure wave forces the fiber into the axial slots thus deforming the fiber and thereby intensity modulating an optical signal passing through the fiber in response to the acoustic pressure. Depth equalization means are included for each embodiment. (Author)

Descriptors :   *PATENTS, *HYDROPHONES, *FIBER OPTICS TRANSMISSION LINES, ACOUSTIC WAVES, SOUND PRESSURE, CYLINDRICAL BODIES, OPTICAL PROPERTIES, FIBER OPTICS, AXES, MODULATION, INVENTIONS, EQUALIZATION, PISTONS, GROOVING, PARALLEL ORIENTATION, SIGNALS, SURFACES, INTENSITY, DEPTH, SLOTS, HELIXES, OPTICS

Subject Categories : Acoustic Detection and Detectors
      Fiber Optics and Integrated Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE