Irreversible effects of random modulation on coherence properties of partially polarized light
Résumé
The effect of random modulations of two electric vector fields on their coherence properties is investigated by analyzing their interference fringes. It is shown that random modulations cannot increase the maximal visibility obtained when the polarization states of the two analyzed electric fields are optimized. This new result generalizes a standard property of perfectly polarized light to unpolarized light and is representative of the irreversible effects of random modulations. It is also proved that another quantity related to coherence properties is also non increasing if the modulations applied to each electric field are uncorrelated.