Newbie questions!!!

[testle]

Hi all,

I got inspired by Phritzler and rfourt ' multiple diodes projects.

I'm thinking building something similar to those.

But what I can't figure out is the optics calculating . I mean the lenses to collimate the beams after they exit the PBS cube.

How can you know what are the right lenses?

I went to melles griot website, but all I found just for collimating a single beam, not for a horizontally (vertically) stack of beams


Any help is appreciated.

Thanks

[danielbriggs]

Try this: http://webphysics.davidson.edu/physl...ics_bench.html
Cheap and cheerful java applet.

If you had a square grid, say 4x4 of beams, treat them as 1 big beam.
For example, take a convex lens with a focal length of 1x and another convex lens with a focal lens of 0.1x, then place the 2nd lens 1.1x from the first lens. This will reduce your big square beam to one 1/10 of the starting size. However divergence will increase 10 fold.
Another way is to take a convex lens of 1x and place a concave lens of -0.1x and place it 0.9x from the first lens. This will have the same effect.

Feel free to change the ratios, they are just for illustration.

Dan

[testle]

Thanks Dan!!!

Now it is all clear to me.

Thanks again.

[testle]

After playing with the applet for a while, I realize that the applet won't let you fix the input beam diameter nor let you know what is the diameter of the output beam.

I mean, if I stack 5 red laser beams out of the Aixiz modules side by side, assuming 1 mm diameter for each beam, hence I have a 5mm diameter beam. Now I'd need a formula to calculate what are the lenses I'd need to make the beam smaller, lets say 2mm diameter.

Still googling like crazy, but got no answer yet.

Can anyone shred some lights?

Thanks

[Laserman532]

first- beams out of an aixiz module are bigger than 1mm
second- if you use the scraping method you will not end up with a 5mm spot
third- nothing beats actually building one

Artist renditions are nice but they are only artist renditions.

[testle]

You right laserman. The beam from the Aixiz module is more like 2 to 3mm.
I can fit 5 beams in a 15mm PBS cube I got from gottaluvlasers. So it is like a 15mm beam.
The task is tighten the beam down to fit the scanner mirrors.

Ofcourse I'll have high divergence beam, but as long as it fits the scanner's mirrors first, and secondly the beam doesn't have to travel to far in a venue, I think the objective is met.

Wang.