Spectral Dependence of Polarized Radiation due to Spatial Correlations

We study the polarization of light emitted by spatially correlated sources. We show that in general polarization acquires nontrivial spectral dependence due to spatial correlations. The spectral dependence is found to be absent only for a special class of sources where the correlation length scales as the wavelength of light. We further study the cross correlations between two spatially distinct points that are generated due to propagation. It is found that such cross correlation leads to sufficiently strong spectral dependence of polarization which can be measured experimentally.Comment: 5 pages, 4 figure

Focal shift of focused flat-topped beams

The phenomenon of focal shift is studied for the case of focused coherent beams showing a flat-topped transverse profile. The model describing such beams is that of flattened Gaussian beams, which, due to their peculiar analytical expression, are particularly fit for the study of paraxial propagation of flattened beams. Focal shifts for the fundamental Gaussian mode and for the field produced by diffraction of a converging spherical wave by a circular aperture are shown to be obtainable by this model as particular cases

Focusing of axially symmetric flattened Gaussian beams

We study the three-dimensional field distribution of a focused axially symmetric flattened Gaussian beam. In particular, exact closed-form expressions for the intensity along the optical axis and at the focal plane are provided, together with a comparison between our results and those pertinent to the case of a converging spherical wave diffracted by a hard-edge circular aperture. Some hints for future investigations are also given

Shape-invariance range of a light beam

A typical axially symmetric light beam on paraxial free propagation maintains the same transverse shape as at the waist plane for a certain range along its axis. We discuss a general procedure for estimating this range. (C) 1996 Optical Society of Americ

Shape-invariance error for axially symmetric light beams

A significant aspect of the propagation of coherent light beams is that the shape of the transverse field distribution changes. In this paper, the concepts of shape-invariance error and shape-invariance range are used to characterize such effects in a quantitative way. Applications of the theoretical analysis to some simple but significant cases are presented

Experimental determination of the size of a source from spectral measurements

We show how spectral changes measurements in a Young interferometer can be used to determine the dimension of an incoherent source. The experimental results confirm the theoretical predictions