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FrozenGate by Avery

Laser beam properties.

solar00

solar00

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Yesterday i tried to bounce the beam off my livingroom window into the sky. (window glass should only reflect a fraction of the light and the rest goes through)

But the distance of the beam still looks the same (although a lot dimmer).

Does this mean that a laser with higher power have the same beam lenght but brighter?
And does it mean that at a certain point there are no more particles to recflect the light?
 





The beam length you are seeing is only an illusion - technically speaking, your beam continues onward until the divergence is so vast that you can no longer detect any irradiance at all. the glass to a certain degree filters the light, and absorbs some of it, and reflects some, and allows the rest to pass through it, albeit on a slight angle. That all depends on the properties of the glass used, though ! ALL of the stories we see about, "This laser has a range of 65 miles..." etc...are all just either estimations, or falsehoods - generated to promote sales in some cases, and in others just put up there, because "Joe's laser shack" has a distance published ! When your laser exits the atmosphere, there will be no "beam" per say, due to the lask of contaminants in a vaccuum - with the exception being lunar dust, space debris, etc...the laser would still go THROUGH the vaccuum - and you would only see it from head on - unless it terminated on some object. Now, I imagine the laser would need to be very powerful, and have tremendous divergence to survive that long of a trip - to check it out, look at a divergence claculator and plug in some random numbers - you will see how large the dot would be at 65 miles, 650 miles, etc....

G !
 
As SenKat says, the apparent distance is just an illusion. Theoretically, if you could shine the beam straight out of your eye, the beam would only look like a point. This is because in your field of vision, the beam doesn't go to the right or left in the plane, it just goes straight, so it only appears as a point.

If the laser is in your hand, shining at an angle, it does move across your field of vision, but as the distance from you gets larger and larger, it moves less and less relatively, until eventually the beam doesn't appear to go on anymore. In truth, the beam keeps traveling, but you end up just seeing the rest of the beam stacked up onto one point in your field of vision.

Sorry if that's a bit confusing - its hard to explain without a pad of paper and some trig, but basically the beam length you're seeing is a trick of your vision - the beam extends on nearly forever.
 
As SenKat was trying to say -- simply put ---

When the beam exits our "dirty" atmosphere into the vaccuum of space, it becomes invisable to the "sender" as a reflection from the suspended crap.
Whatever amount of the beam which does get out goes on forever until it hits something like space dust.

Mike
 
wickedlasers said:
refection can lost many power,glass and water is same
Click to expand...

Well, LOOKIE ! Welcome to the forum, Wickedlasers ! Nice to see more company representation on here !!!
FYI - if it WAS actually you all calling Greg Stoner last week - and I was laughing on the phone, you can call back, as I thought it was a prank call - sorry if you thought I was rude !

Greg
 
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