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

Possible range wit focus

nc9210 said:
@lasersbee
Do you know a lens with a very high focal length?

@Arayan
Thank you for showing me the difference. If i expand the beam first and then focus for a long distance it will reduce uniformly and divergate again behind the focus. Ist this right? This looks like my experiment with the 2 magnifiers. But in my experiment i loose many light :-(

@steve001 WOW!

I have never seen anything like that. Do you know more about the used equipment? It seems to be a teleskope? Is it moified in any way? And what kind of laser is used? This looks like a fiber-bound type with any type of optic attached?

regards
Nicole
Click to expand...

Like others have said. It is a reverse telescope, a Galilean telescope also know as a refractor telescope. Look up Galilean laser beam expander.
 





OK, i begin to understand. And now (i read the laserglow pages) i know that the used laser is a DPSS type. The beam expander used in he video is not shown at laserglow. Is this a prototype?
As shown at laserglow a beam expander available from stock is aplicable for low distances only. I think, i try a telescope and will see what happens.

Regards
Nicole
 
...As shown at laserglow a beam expander available from stock is aplicable for low distances only.
Click to expand...
I have not read the specifications but I believe it can also be used for long distances

LPF thread
 
Last edited:
this diagram shows the possibilities:
beam_diameter.jpg

(If not allowed to post pictures i will delete it immediately)

I've just tested a " 3x video tele attachment" with a really good result (5mm and sharp).
But the beam was not expanded, only summarized. The next days i check this item at a long distanceand report what happens ...
Then i used a binocular 8x40 but the point is not small and not sharp :-(

Regards
Nicole

PS @lasersbee
there are more items on ebay, but no one ist described especial for long distance.
Only 2 items are 10x extenders - unfortunally both galilean types ...
 
Last edited:
It is not important that it's Galilean (almost all beam exoaders are galilean) or not as the result is the same: small divergence!

See the arrow in picture... ;)

The laser "burning power"= (power)/3.14(beam diameter+beam divergence*distance)A2/2
 

Attachments

  • beam_diameter.jpg
    beam_diameter.jpg
    112 KB · Views: 188
Arayan said:
It is not important that it's Galilean (almost all beam exoaders are galilean) or not as the result is the same: small divergence!

See the arrow in picture... ;)

The laser "burning power"= (power)/3.14(beam diameter+beam divergence*distance)A2/2
Click to expand...

The important difference between Keplerian and Galilean is the former has a longer construction length the latter a shorter length.
 
You must log in or register to reply here.


Back
Top