Low Frequency Anti-Interference Mechanism of Axial Stretching Fiber Laser Hydrophones

Abstract

For the axial stretching fiber laser hydrophone, a fiber laser is often exposed to flexural interference. A theoretical model for the flexural vibration of a fiber laser was therefore constructed in this paper to explore the low frequency anti-interference mechanism for the frequency response of an axially tensioned fiber laser hydrophone (FLH). A specific packaging structure was used for finite element comparison and simulation. Packaged FLHs were tested for frequency response. The simulation and test results reveal that the flexible attachment at both ends of a fiber laser leads to lower amplitude of flexural vibration compared with rigid attachment, which therefore promotes a flat acoustic response curve of an FLH. The analysis given in this paper can be taken as a basis for improving the packaging technique.

Keywords

• fiber laser hydrophone
• flexural vibration
• flexible attachment
• rigid attachment