A Sensitivity-Enhanced Fiber Optic Microphone Based on Packaging Design

A design method of composite sensitized optical fiber microphone based on package is proposed. First, finite element simulation experiments were carried out to analyze the effects of Young’s modulus (
${E}$
) and Poisson’s ratio (
$\mu $
) of packaging materials, as well as their size radius and height on the sensitivity of optical fiber microphones (OFMs), and the above analysis was verified by experiments. Based on the above conclusions, a simple resin-packaged sensitized optical fiber microphone (ROFM) with good protective properties and high sensitivity has been prepared by using aspartate polyurea resin (APR). Acoustic tests show that the ROFM maintains full frequency sensitization in the range of 100–3400 Hz and has a good linear sound pressure response. In particular, the ROFM achieves a 13.1–40 dB enhancement over the 100–1200-Hz human acoustic wave concentration range, averaging about 27.5 dB, and the frequency response is flatter. These results show that the ROFM has high sensitivity and high fidelity, and it is suitable for acoustic detection sin the range of human voice. At the same time, the package design sensitization method proposed in this article has wide applicability to OFMs and has broad application prospects.