Patent · US Expired

Optical fibre hydrophone

US4536861A · kind A · utility

21Cited by
5References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 27, 1984
Grant dateAug 20, 1985
Priority date
Expiry dateFeb 27, 2004

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01H9/004
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

The 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.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.