Optimization of excitation of fiber Fabry-Perot tunable filters used in swept lasers using a phase-correction method

In this paper we investigate a phase-correction method for compensation of the nonlinearity of conventional wavelength-swept laser sources based on a fiber Fabry-Perot tunable filter as a wavelength selective element. A triangular waveform signal is commonly used to drive the filter. We, however, extract the zero crossings from the interferograms and modify the shape of the triangular signal accordingly. This algorithm was tested for different values of the optical path length difference in the interferometer setup. Significant compensation for the nonlinearity of the filter was obtained.