Abstract
This paper describes the concept of cross-spectrally pure light, implications of statistical similarity of an optical field on its cross-spectral purity and cross-spectrally pure fields. First, the concept of cross-spectral purity of light is analysed in the space-frequency domain by taking into account the vectorial nature of the radiation, and the conditions and reduction formula are obtained. Then, by utilizing statistical similarity, the relationship between cross-spectral purity and spatial coherence is explored in the electromagnetic field. Last, the conditions for cross-spectrally pure fields are discussed, the polychromatic plane wave and the far field produced by a planar, secondary, stochastic electromagnetic source are studied as examples, and moreover, the relationship between cross-spectral purity and spatial coherence, which we have drawn, is verified during the study.
Acknowledgements
Authors are indebted to the reviewers for their invaluable comments and suggestions.
Funding
This work was supported by the [National Natural Science Foundations of China] under [grant number 61107011], [grant number 61205121]; [Provincial Natural Science Foundation of Anhui] under [grant number 1208085QF111]; and [Fundamental Research Funds for the Central Universities] under [grant number J2014HGBZ0170].