What is the origin of the strange shadow in a laser beam?

Thread starter paul-g
Start date Oct 14, 2011
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Laser Shadow Strange

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The discussion centers on the phenomenon observed when a laser beam is directed at a small object, resulting in a bright spot in the center of the shadow. This effect is known as Poisson's spot, or Arago's spot, which occurs due to the wave nature of light and diffraction. The bright spot appears because light waves bend around the object and interfere constructively at the center of the shadow. The conversation references a Wikipedia article for further reading on the topic. Understanding this phenomenon highlights the complexities of light behavior in optics.

Oct 14, 2011

paul-g

Hello!

I have for you some questions about the lasers. When ordinary laser beam directed at a small ball (few millimeters) on the screen I saw a bright spot in the middle of the shadow. What it is due?

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Oct 14, 2011

Andy Resnick

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Are you referring to Poisson's spot?

http://en.wikipedia.org/wiki/Arago_spot

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