Noise equivalent pressure of an novel acousto-optical system dedicated to Deep Sea

Sensors based on optical fibers have well known advantages over conventional electromechanical sensors. They offer electrically passive operation and immunity from electromagnetic fields because the fiber is entirely made with dielectric materials. We present a novel acousto-optic system structure. The pump laser, circulator and receiver system including one interferometer used as discriminator, must be placed on electronic board with low electric consumption (<; 1A). It is demonstrated we can detect very low acoustic signal, the same level as Deep Sea State Zero Noise if the acoustooptical sensitivity is sufficient high. Hence, the Noise equivalent pressure of this novel acoustooptical system is optimized.