Damping of a Laser Beam: Understanding the Science and Equations

AI Thread Summary
The discussion focuses on the equations that describe the damping or extinction of laser beams as they propagate through a medium. Key factors influencing this damping include the density of air and the distance traveled, with Rayleigh scattering identified as a primary source of loss at shorter wavelengths. The relationship between power loss and scattering is expressed through the equation P = P_0*e^(-σx), where σ represents the scattering cross section. Participants share insights and references, helping clarify the concepts involved. The conversation concludes with a participant expressing gratitude for the information that enables further calculations.
dmriser
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This is a question for knowledge not for any assignment, but I was wondering what type of equation describes the damping or extinction that the light beam coming from a laser endures. I googled and couldn't find much although I may be using the wrong terminology. Could someone point me toward a reference or enlighten me on the subject?

I assume that the density of air will come into play as there will be more scattering and so will the distance but I can't find any equations or even begin to derive my own.

Thanks
 
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Net power loss will be determined by the loss induced by the medium that the laser beam propagates through.

Rayleigh scattering would be the primary source of loss at short wavelengths. Rayleigh scattering is indeed dependent on the particle density;

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

The scattering cross section is related to the linear loss the exponential relationship P = P_0*e^(-/sigma*x).

Claude.
 
That does the job, I can now make the calculations I wanted.. Thank you
 
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