Direct airborne acoustic wave modulation of Fabry–Perot fiber laser (FPFL) over 100 kHz of operating bandwidth
Document Type
Article
Publication Date
1-1-2012
Abstract
The idea of applying a simple Fabry-Perot fiber laser (FPFL) set-up in a free-running condition as an acoustic sensing medium is proposed. Conventional optical microphone requires a stringently aligned diaphragm to mediate the acoustic impedance mismatch between air and silica fiber. Motivated by the difficulty of optical sensing of airborne acoustic waves, a new sensing method is proposed to sense acoustic waves without the assistance of a diaphragm as transducer. By studying the output power fluctuation of the FPFL, the operating bandwidth and sensitivity of the proposed sensing method are determined. The tunability of the resonant frequency from 5 kHz to 85 kHz allows sensing ofacoustic waves in the range of 100 Hz to 100 kHz. Tuning of the resonant frequency can be performed by changing the optical pumping power from as low as 10 mW to 68.5 mW or higher.
Keywords
Acoustic waves, Bandwidth, Diaphragms, Fabry-Perot interferometers, Fiber lasers, Natural frequencies, Optical pumping
Divisions
fac_eng,PHYSICS
Publication Title
Applied Optics
Volume
51
Issue
15
Publisher
Optical Society of America