Describe how optical fibers used as hydrophones.
Optical fibers are employed as hydrophones for sonar and seismic applications. Each hydrophone systems along with more than one hundred sensors per fiber cable have been extended. Hydrophone sensor systems are employed by the oil industry and also a few countries' navies. Bottom-mounted hydrophone arrays and towed streamer systems both are in utilize. The German company Sennheiser expanded a laser microphone for use along with optical fibers.