Optical frequency-domain reflectometer with temperature change of the DFB laser wavelength

In this paper the concept and design of a high resolution optical frequency-domain reflectometer is presented. Realization of the measurement is based on the frequency sweeping of a distributed feed back laser, which is obtained directly through changing the laser temperature. The measurement system and achieved results are also shown. A control circuit using Peltier pump for temperature control was additionally made. With the use of this circuit the laser was alternatively heated or cooled, with the possibility of the temperature monitoring. A computer program for system driving and synchronisation was developed in MatLab and serves also for data acquisition and processing. The resulting reflections obtained from the acquired data are graphically displayed.