Based on an interpretation of the operating principle of passive polar
ization converters in terms of rotated vectorial eigenstates, it is sh
own that polarization rotation effects in angled facet passive convert
ers can be maximized. Optimization of structure design achieves a devi
ce free of longitudinally-periodic structure with a very short convert
ing length and low losses. Performance superior to any passive polariz
ation converter reported in the literature is predicted for the device
modeled with a vectorial numerical approach based on a finite-element
scheme.