High-sensitivity, low-noise, remote optical fiber
Monomodal optical fibre hydrophone operating by the elastooptical effect
Optical acoustic sensor
Optical resonator single-mode fiber hydrophone Patent #: 4446543
ApplicationNo. 06/583644 filed on 02/27/1984
US Classes:367/149, Exclusive-type receiver356/477Using fiber or waveguide interferometer
ExaminersPrimary: Tudor, Harold J.
Attorney, Agent or Firm
International ClassG01H 9/00 (20060101)
Foreign Application Priority Data1983-02-25 FR
AbstractThe invention relates to a monomodal optical fibre hydrophone operating by elastooptical effect, which has an interferometer structure comprising a measuring arm, in which is arranged a very long monomodal optical fibre immersed in the interaction medium in which propagates the soundwave. A phase displacement is induced by an elastooptical effect on the soundwave propagating in the fibre, by a soundwave producing an acoustic pressure field in said medium. A reference arm establishes a reference optical path and the phase displacement, linked with the sound wave, is detected by interferometry between the two optical waves coming from these two arms. This two-armed interferometer is terminated by a photorefractive medium used as an interactive reflector in accordance with the four-wave interferometry principle.