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ArcticMyst Security by Avery

General laser question

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I was just thinking....
When shining a laser through our normal air that we breath, the energy of the laser gets weaker the further away it is from the laser source. From what I have understood...this is caused by particles, water vapor, and possibly many other things that is in our air.

Now my question is...If I had a laser in outer-space, which is essentually one large vacuum, would my laser output degrade as much or very little, thus making the light travel an infinite distance?
 





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Light will travel infinitely far in a total vacuum, but space isn't a total vacuum. There are still particles that will eventually block some photons, but any photon that isn't blocked will continue indefinitely.
 

Ash

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Being that outer space is (mostly) a vacuum, your laser light should (theoretically) travel an infinite distance. Also, you wouldn't be able to see the beam at all because there are no particles for it to shine through (or reflect off).
In theory, if daguin was standing on the outside of a space station with an LPM, and I was standing on top of a space shuttle and I aimed a laser (with zero-divergence) at his LPM; at whatever distance 10-10,000 miles, the reading should be exactly the same.
Simpsons_-_Geek_Scientist.gif
 
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Being that outer space is (mostly) a vacuum, your laser light should (theoretically) travel an infinite distance. Also, you wouldn't be able to see the beam at all because there are no particles for it to shine through (or reflect off).
In theory, if daguin was standing on the outside of a space station with an LPM, and I was standing on top of a space shuttle and I aimed a laser at his LPM; at whatever distance 10-10,000 miles, the reading should be exactly the same.
Simpsons_-_Geek_Scientist.gif

Maybe with zero divergence.
Diffraction will not be an issue, but your beam of light will diverge regardless.
 
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I was just thinking....
When shining a laser through our normal air that we breath, the energy of the laser gets weaker the further away it is from the laser source. From what I have understood...this is caused by particles, water vapor, and possibly many other things that is in our air.

Now my question is...If I had a laser in outer-space, which is essentually one large vacuum, would my laser output degrade as much or very little, thus making the light travel an infinite distance?
Didn't you read this post?:na:
http://laserpointerforums.com/f44/more-idiots-lasers-49096.html:crackup:
Seriously now, the above statements are spot-on.
 
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Ah, that's what i was going to ask next. I'm not aware of how open air affects divergence, as opposed to a vacuum.
 

Ash

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The divergence shouldn't matter if daguin's LPM has a large enough thermopile sensor. :thinking:
 

daguin

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The divergence shouldn't matter if daguin's LPM has a large enough thermopile sensor. :thinking:

This is my largest thermopile. Yeah. That's a Kryton Groove sitting inside it.
IMG_0639.jpg


At 1.3mRad this thermopile would be good for up to about 500 feet. How far is it to the moon again? :na:

Peace,
dave
 
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This is my largest thermopile. Yeah. That's a Kryton Groove sitting inside it.
IMG_0639.jpg


At 1.3mRad this thermopile would be good for up to about 500 feet. How far is it to the moon again? :na:

Peace,
dave
You MUST be kidding me.

What on EARTH is THAT?!

Is that used to measure high end CO2 lasers, or anything else of that magnitude? Seriously, what is that used for?

It must be for measuring lasers if you are blind and having difficulties aiming at puny and tiny sensors. You cannot miss that one even if you would want to.
 
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Thanks for the answers everyone. They pretty much summed up what I had going on in my head. :) Pretty cool to think about. :)
 




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