光纤水听器浅析

Analysis of Optic Fiber Hydrophone

光纤水听器按传感原理分为强度型、干涉型和光纤光栅型等。强度型光纤水听器,根据光纤微弯损致使光功率变化。干涉型光纤水听器基于光学干涉,通过水中声波对光纤的压力而改变的光纤纤芯折射率或长度所引起的光纤中传播光束光程变化,通过检测其相位得到水声信息。光纤光栅型光纤水听器基于原理,其传感光栅周围的应力随水中声压变化。

According to the sensing principle, the optic fiber hydrophone includes the light-intensity modulation hydrophone, interference, and FGB, The light-intensity modulation hydrophone changes the optical power based on micro-bending. The interference hydrophone is based on optical interference. Through changing the pressure from underwater sound wave to fiber, change the refractive index of optical fiber core or length. Then, change the optical distance in optical fi^er .and acquire the water sound wave information by detecting the phase. The FBG hydrophone is based on principle, the pressure around sense grating changes with the underwater sound pressure.