An example of an optical setup that displays Fresnel diffraction occuring in the near-field. On this diagram, a wave is diffracted and observed at point ?. As this point is moved further back, beyond the fresnel threshold or in the far-field, Fraunhofer diffraction occurs.

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An example of an optical setup that displays Fresnel diffraction occuring in the near-field. On this diagram, a wave is diffracted and observed at point ?. As this point is moved further back, beyond the fresnel threshold or in the far-field, Fraunhofer diffraction occurs.