How Does Laser Interaction Impact Air?

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High-energy lasers can ionize the air they pass through, leading to various effects, while average lasers have minimal impact. A laser beam does not actually "travel" through air in the traditional sense, as it is a light-emitting device rather than a projectile. When a laser has a short pulse duration and high power, it can experience filamentation, balancing nonlinear Kerr self-focusing and plasma generation. This interaction creates a laser beam that maintains its focus over distance, which is beneficial for applications like LIDAR. Overall, the discussion highlights the complex interactions between lasers and air under specific conditions.
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Does laser traveling through air affect the air it travels through?
 
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High energy lasers will ionize the air around them and do all sorts of funny things. The average laser beam will do nothing. "Laser" does not travel through air, because "laser" is a light emitting machine, not a "lasers go pew pew" ray.
 
A laser with a sufficiently short pulse duration and sufficiently high power will undergo what is known as filamentation, which is actually a dynamic balance between two opposing mechanisms - nonlinear Kerr self-focusing, which is the phenomenon whereby the local refractive index is dependent on irradiance. This essentially turns the air into a weak lens, causing the laser beam to converge (hence the term self-focusing). The opposing effect is plasma generation - which also turns the air into a weak lens, albeit a diverging one.

The combined effect of these two phenomena is a laser beam that does not spread out as it propagates (however it is not a soliton). This is especially handy for LIDAR type applications.

Claude.
 
dst said:
High energy lasers will ionize the air around them and do all sorts of funny things. The average laser beam will do nothing. "Laser" does not travel through air, because "laser" is a light emitting machine, not a "lasers go pew pew" ray.



All i got to say is that is the funniest quote i have ever heard. "pew pew" LOL. thanks for the comic releif
 
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