Calibration and stability of highly sensitive fibre based laser through relative intensity noise

Abstract

This work is concerned with the characterization of the fiber based laser sensor by means of relative intensity noise (RIN). The characterization has been done by an electrical based measurement system, which has been accomplished by the implementation of an optical receiver setup. The optical receiver setup has been built by using commercially available low noise amplifier (LNA), Bias Tee, and fast photodiode (FPD). Besides the optical receiver setup designing, software in Labview has been built and implemented to enable easy and fast measurement of data from measurement instruments. Using the self assembled optical receiver and an electrical spectrum analyzer (ESA), optical fluctuation ’noise’ of the fiber based laser sensor has been measured. We have found good agreement between the measurement results taken by our measurement setup and costly Agilent RIN measurement setup. Also, average RIN over wide frequency range has been calculated and discussed for different operating states of the laser sensor. The results are applicable in the field of an optical sensor.