"Single-shot phase-shifting interferometers have become a de facto standard in interferometry for the study of fast dynamic phenomena and/or to achieve low-sensitivity to environmental vibrations. In particular, this dissertation work focuses on the study of pixelated phase-mask interferometers, which are commercially available solutions that encode four phase-shifted samples into a single-image pixelated-carrier interferogram. The earliest phase-demodulation methods for pixelated-carrier interferograms used to rely on classic approaches such as the spatial Fourier demodulation and temporal phaseshifting algorithms (PSAs). However, implementing these phase-demodulation methods for pixelated-carrier interferograms has the following drawbacks: the input data needs to be rearranged in order to apply the algorithms, the quality of the estimated phase decreases due to an intrinsic approximation error on the demodulation method, and the resolution of the output signal is reduced to a quarter of the original one. In 2010 it was demonstrated that the synchronous demodulation of pixelated-carrier interferograms has none of the above mentioned drawbacks. However, since the pixelatedcarrier cannot be described as a linear function, additional work was required in order to assess this phase-demodulation method against the most commonly observed systematic errors in Interferometry: additive white Gaussian noise (AWGN), detuning error and highorder distorting harmonics. In this dissertation work are deduced the figures of merit of the synchronous demodulation method for pixelated phase-shifted interferograms, and two algorithmic approaches are proposed to cope with AWGN and detuning error. Moreover, two experimental variants are proposed to enhance the harmonic rejection capabilities of this technique: by increasing the number of the phase-shifted samples and by means of spatio-temporal phase demodulation."