Link to Possible cheap adj. Beam Expander

cameras, telescopes, you can also pull lenes from micrscopes iv notice the older ones really pushes and widens the beam ill send pics of diffrerence.

Count me in. The few i looked at were priced waaaay over my head.

Well, i made some experiments with this thing, that i got from DX (just cause now i have a better one from Vivitar )

It's not cheap as the other similar ones, but this one have the internal tube in metal, and a longer course (for act both as microscope and telescope), so it's practically already a Galileian expander, so i said, why not try ?

IT WORK

You just need to take away the Porro prism assembly (AKA "inversion" prism), that you don't need in a beam expander and that cause some more power loss if left in place ..... for do that, unscrew the eyepiece, then unscrew the blocking disk, drop out the prism assembly (are the 2 parts i circled in red), and screw back the eyepiece ..... no need to place back also the disk, its only use is for keep the prism assembly in place ..... and ofcourse need to build some sort of adapter, taking away the gum paralight from the eyepiece (thing that you have to do also with other systems, anyway ), and, voila', a ready-to-use Galileian beam expander, with glass AR coated lenses.

Lenses have some sort of AR treatments, also if not optimized for lasers, they are a lightly blue tinted, so it will work better for red and green beams, than for blue, probably.

Still need to do decent optic measurements (no time at the moment), but from the first trials, using a simple "cheap" 50mW green module i got times ago from o-like, at 30 meters the dot is around 11mm dia without the expander, and around 5mm with the expander ..... ofcourse, as any other expanders, you have no more "straight" beams, from it, cause it's bigger than before, at the expander output, but after all, the purpose of an expander is to focus to long distance, not to burn at close distance, so i suppose it's not a problem


EDIT: sorry Hak, i just noticed that was a GB feeler, no intentions to ruin it ..... just to share informations :beer:

:beer::beer:

N/P
mine turned out to be not so good. but cheap ~$17.50 I was able to attach it to madogs 532/600 before I shipped it to him. I used the JETL BE adaptors- but it needs to have another pair of tapped holes as it only has two ATM. pics added in one hour- brb