Question

Explain the phenomenon of Poisson's spot. How does it occur?​

Answer 1

Answer:

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. ... When light shines on the circular obstacle, Huygens' principle says that every point in the plane of the obstacle acts as a new point source of light.

Answer 2

$\: \huge\sf\underline \red{\underline{αɳรωε૨࿐☟}}$

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. ... When light shines on the circular obstacle, Huygens' principle says that every point in the plane of the obstacle acts as a new point source of light.