Encyclopedia > Arago spot

  Article Content

Arago spot

An Arago spot is a bright point which, owing to diffraction, appears at the center of the shadow of a circular object in light from a point source[?]. The diffraction pattern of a circular object has considerable interest due to the historical part it played in the wave theory of light. Siméon Poisson deduced from Augustin Fresnel's theory the necessity of a bright spot at the centre of the shadow of a circular opaque obstacle. With this counterintuitive result Poisson hoped to disprove the wave theory; however Dominique Arago experimentally verifed the prediction and today the demonstration goes by the name "Poisson's (Arago's) spot".



All Wikipedia text is available under the terms of the GNU Free Documentation License

 
  Search Encyclopedia

Search over one million articles, find something about almost anything!
 
 
  
  Featured Article
Thomas a Kempis

... "little hammer." In 1395 he was sent to the school at Deventer conducted by the Brethren of the Common Life[?]. He became skilful as a copyist and was thus ...

 
 
 
This page was created in 23.9 ms