Property constant along rays non-negativity coherence wavelength cross term traditional light field always constant always positive only incoherent zero no observable light field nearly constant any coherence state for any wavelength has cross term augmented light field only in the paraxial region positive and negative WDF has cross term Rihaczek no; linear drift complex reduced cross terms

benefits & limitations ability to propagate representing wave optics simplicity of computation adaptability to current pipe line near field far field traditional light field x-shear no very simple high yes observable light field not x-shear modest low augmented light field WDF Rihaczek better than WDF, not as simple as LF