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Summary
DescriptionAiry spot overlap.png
English: The original objects being imaged are two separated points; when the image is reconstructed by the final objective lens or mirror, the diffraction pattern of the objective aperture (i.e., the Airy disk) is convolved with the two points. When the peaks are separated by around 1 wavelength/NA, they are effectively merging. For this situation, the full-width half-maximum is ~0.6 wavelength/NA. Ref.: B. E. A. Saleh and M. C. Teich, Fundamentals of Photonics, (c) 1991, John Wiley & Sons, Ch. 4 and Appendix A.
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