Stabilizing operation point technique based on the tunable distributed feedback laser for interferometric sensors

• A stabilizing operation point technique based on the tunable Distributed Feedback Laser is proposed. The technique can be used for interferometric sensors quadrature demodulation.
• By introducing automatic lock quadrature point and wavelength periodically tuning compensation into an interferometry system, the operation point of interferometric system is stabilized when the system suffers various environmental perturbations.This system has goodtemperature stability.
• The experiments have been performed using the prosed technique to interrogate an extrinsic Fabry–Perot interferometricvibration sensor and a diaphragm-based acoustic sensor.

We describe a stabilizing operation point technique based on the tunable Distributed Feedback (DFB) laser for quadrature demodulation of interferometric sensors. By introducing automatic lock quadrature point and wavelength periodically tuning compensation into an interferometric system, the operation point of interferometric system is stabilized when the system suffers various environmental perturbations. To demonstrate the feasibility of this stabilizing operation point technique, experiments have been performed using a tunable-DFB-laser as light source to interrogate an extrinsic Fabry–Perot interferometric vibration sensor and a diaphragm-based acoustic sensor. Experimental results show that good tracing of Q-point was effectively realized.