Arago spot
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In optics, the Arago spot, Poisson spot, or Fresnel spot is a bright point that appears at the center of a circular object's shadow due to Fresnel diffraction. This spot played an important role in th
Notation for calculating the wave amplitude at point P1 from a spherical point source at P0.
The on-axis intensity at the center of the shadow of a small circular obstacle converges to the unobstructed intensity.
Numerical simulation of the intensity of monochromatic light of wavelength λ = 0.5 μm behind a circular obstacle of radius R = 5 μm = 10λ.
Arago spot experiment. A point source illuminates a circular object, casting a shadow on a screen. At the shadow's center a bright spot appears due to diffraction, contradicting the prediction of geometric optics.
Siméon Denis Poisson
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Baron Siméon Denis Poisson was a French mathematician and physicist who worked on statistics, complex analysis, partial differential equations, the calculus of variations, analytical mechanics, electr
The name of Poisson (first from the right) inscribed on the Eiffel Tower
Poisson's 1804 portrait by E. Marcellot, now in the collection of the École Polytechnique.
Poisson's equations for electricity (top) and magnetism (bottom) in SI units on the front cover of an undergraduate textbook.