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



M462 -> Binoculars as a Beam Expander

aaronnoraa

Active member
Joined
Jun 20, 2015
Messages
178
Points
43
Just some pics of a M462 running at quarter power through some Nikon binoculars that had been put to work as a beam expander and a picture of the very super extra high tech setup.
 

Attachments




aaronnoraa

Active member
Joined
Jun 20, 2015
Messages
178
Points
43
How small can you focus the dot and at what distance?
I had it focused to infinity so that the output from the binoculars was the same size across the entire length of the beam (as close as my judgement could make it, visually the spot looked the same on the wall as it did at the output of the binoculars). To focus it I just used the focus wheel on the binoculars. Easy Peasey. What I found interesting is that the divergence was so low at 10x expansion that the beam, which normally starts out vertically oriented at the output of the laser aperture and transitions to a horizontal stripe about 6 feet out as the fast axis catches up with and overshoots the slow axis in size, didn't seem to budge at all in stripe thickness and wasn't visually beginning to change proportions, still very much vertical about 30 feet away on the wall.

I just realized you may have been asking how small of a spot I can get *if* I focus it down. I didn't check that, I'll try it tomorrow and report back, but I can answer the other part of that question.. the distance will be whatever random distance the focal point ends up being at after carelessly spinning the focus wheel on the Nicons :)
 
Last edited:

Snecho

Well-known member
Joined
Oct 2, 2019
Messages
834
Points
93
I love your super very cool profile picture 🤣
 

CDBEAM777

Well-known member
Joined
Feb 25, 2010
Messages
1,644
Points
113
Nice...It is McGuiverish....BUT...it works...Hats off to you ! CDBeam
 

Richie89

Well-known member
Joined
May 9, 2015
Messages
1,159
Points
113
I miss my M462 :( I accidently blew it up. never making that mistake again. very cool indeed
 

Cyparagon

Well-known member
Joined
Sep 12, 2007
Messages
9,804
Points
113
Monoculars/binoculars/telescopes are often very picky about entrance angle, and often have comparatively very high losses. Even with AR coatings, there's way more optical elements than necessary for simple expansion, so you're gonna lose maybe 20-50% of your power. Also in the original application, since the objective gathers a lot of light to begin with, it's "fine" if a bunch is lost.



But yes, they work in a pinch.
 




Top