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arXiv · 2212.02328

Double-Conjugation Law in Geometrical Coherent Imaging. Application to Gaussian Beams

Pierre Pellat-Finet
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Abstract

A centred system forms the coherent image of the optical field on a spherical cap, taken as an object, on another spherical cap, whose vertex and curvature center are the respective paraxial images of the vertex and center of the object cap. That ``double-conjugation'' law, usually obtained in the framework of a scalar theory of diffraction, is deduced from concepts of geometrical optics. A magnification law between radii of conjugate spherical-caps extends the notion of longitudinal magnification to finite distances, and generalizes the longitudinal Lagrange-Helmholtz formula. Applying the double-conjugation law to imaging Gaussian beams shows that those beams perfectly obey geometrical optics laws.

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Pierre Pellat-Finet. 2022-12-05. Double-Conjugation Law in Geometrical Coherent Imaging. Application to Gaussian Beams. https://arxiv.org/abs/2212.02328

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