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arXiv · 1512.02246

Unitary rotation and gyration of pixellated images on rectangular screens

Alejandro R. Urzúa·Kurt Bernardo Wolf
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Abstract

In the two space dimensions of screens in optical sy stems, rotations, gyrations, and fractional Fourier transformations form the Fourier subgroup of the symplectic group of linear canonical transformations: U(2) F $\subset$ Sp(4,R). Here we study the action of this Fourier group on pixellated images within generic rectangular $N_x$ $\times$ $N_y$ screens; its elements here compose properly and act unitarily, i.e., without loss of information.

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Alejandro R. Urzúa, Kurt Bernardo Wolf. 2015-12-07. Unitary rotation and gyration of pixellated images on rectangular screens. https://doi.org/10.1364/josaa.33.000642

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