Direction of Light to our Eyes

Thread starter at94official
Start date Aug 6, 2015
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Direction Eyes Light

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When using a laser pointer in a direction away from the eyes, the visibility of the beam is due to light scattering by particles in the atmosphere, such as dust. This scattering allows the light to become visible even when it is not directly traveling towards the observer's eyes. The phenomenon can be understood through basic principles of light behavior rather than a specific equation. The discussion highlights the importance of atmospheric conditions in the perception of light. Understanding these principles clarifies why the laser beam can be seen despite its direction.

Aug 6, 2015

at94official

Hi everyone! I just wonder when I use a laser pointer to other direction. How come our eyes able to see it? Since the light is traveling towards the other direction and not to our eyes. Is there an equation associated with that or its just basic logic is needed to understand why this happen.

Skyte

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Aug 6, 2015

Borg

Science Advisor

Gold Member

You're seeing light that is scattered by dust in the atmosphere.

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