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

Buy Site Supporter Role (remove some ads) | LPF Donations

Links below open in new window

FrozenGate by Avery

how laser energy loss over distance????

Joined
Aug 15, 2014
Messages
2
Points
0
hi dears
can any one give me informations about
How quickly do laser beams lose their power as they travel?
thanks
 





Energy is only "lost" as it is absorbed by the matter it is passing through (air, usually). In a vacuum no energy would be lost, but the beam would still spread out.
 
Depends on so many other factors like dust or fog in the air, it's basically a "how long is a piece of string" question.
 
Depends on the focus of it. You can determine the power by doing:

Order of magnitude of the beam's solid angle is approximately wavelength/area of the laser's output aperture is approximately (the vertex angle of divergence)^2

This will tell you it's spread and therefore you can calculate the beam's focal point and therefore at what distances you are receiving full power in a vacuum

An example is:
wl: 500nm
Area of aperture: 5mm^2

So:
Order of magnitude of the beams solid angle (estimate sign) (500)^2*10^-18 m^2/5^2*10^-6)=10^-8 so the vertex angle of divergence is 1/10 milliradians

That is just for checking the power without the lens or an lpm

Hope this helps :D

PLEASE correct me guys if this is the wrong formula.
 
Last edited:


Back
Top