This paper presents recent space resolved experimental study of polarization of He-like argon spectra in plasma focus. Consideration is made on dominant anisotropy mechanisms responsible for preferential orientation of different excited states at the moment of de-excitation in dense hot plasmas. Essential attention is given to alignment along the resulting electromagnetic field created as by exciting electron and also by the local electromagnetic field existing inside the plasma. Such study would provide the tool to diagnose distribution of electromagnetic fields and to count for anisotropy effects when calculating plasma parameters.