F-P geophone medium

A method of broadening frequency bandwidth and improving sensitivity of a Fabry-Pérot (F-P) geophone is proposed, and the corresponding high-performance device is designed and demonstrated experimentally. The theoretical model of F-P geophone based on wavelength demodulation is established thoughtfully, and while the sensitivity is effectively improved, the frequency band can be effectively extended under the determined higher resonance frequency, and the cross-sensitivity can be suppressed. Based on this design idea, the structure of the F-P cavity geophone filled with sensitizing medium is cleverly designed. The corresponding geophone is fabricated.