Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers



Laser Pointer Store

Lasers in rain question

jbtm

New member
Joined
Mar 22, 2010
Messages
495
Likes
30
Points
0
I dont have any pictures, Because I do not like shining lasers into the sky (even if its at an angle) so I sat there, inspected all around, nothing. and did a quick less than 1 second flash on.

Tonight, it's a dusty rain. Looks like fog with street lights (very little) but in lasers, you can see its a cold dusty rain.

The question, Why does it appear the laser just stops, and appears to be at roughly 100ft away? Is this due to water refraction, and it hits a limitation where the beam is diffracted so much it doesn't go forth?

Situation one: 420mA Red laser is pointed. It appears to be around 100ft away that i see the dot just stop, the dot being what looks to be 1cm diameter (from my view).

Situation two: Green 200mw laser set to focus close. This means at 30ft, my dot is 5" diameter. I pointed this to the skys, what looked to be a 1ft dot, 50-100ft away floated in the sky. Like a spot light, it just stops.

What exactly causes this sudden stop? Of course if my green laser was set to infinity, it would go much farther.
 

jbtm

New member
Joined
Mar 22, 2010
Messages
495
Likes
30
Points
0
At the diffraction rate this was, i didn't think it would hit clouds since those are usually over 5,000ft up. It's not foggy. The clouds, since its raining, is still many thousand feet up. I just didn't think at the rate of diffraction, the dot would look that size. I figured it would appear much larger, since at 30ft its 5" diameter, and 60ft its more than double, almost 12" at the dot. I figured at this rate, it wouldn't be near as bright as it was if it was hitting clouds at a couple thousand feet up...
 

Flaminpyro

New member
Joined
May 4, 2009
Messages
5,462
Likes
551
Points
0
It only looks like it stops and at that point most of it's power dose stop but some small amount still keeps going till it is finaly asorbed by the moisture in the air.
Find a field of tall grass and sweep the beam through it, it looks pretty cool ;)
 




Top