Spectroscopy of partially coherent fields at geometrical-image plane and Fourier transform plane of a lens

摘要

An experimental study of the spectra of a partially coherent field, propagating beyond an optical system (a lens), reveals that no spectral shift takes place on the geometrical-image plane, while large blue shift occurs at the back focal plane of the optical system for on-axis points of observation. Different light sources taken for the study are (i) partially coherent fields produced by a multimode laser and (ii) a quasi-homogeneous source with different degrees of spatial coherence. These results are consistent with the theory and might find applications in metrology.