WTB: beam expander for CO2 (10,6um)

[dar303]

Hi,

I have a CO2 laser that has a 4mm output beam and for optimum focus with my 12,5mm lens the laser needs to be placed a couple of meters from the lens. I can't do that and would rather put the laser 5 - 15 cm from the cutting nozzle so I need some form of beam expander.

Does anybody have something suitable to sell for a decent price? This is a hobby project (laser cutter cnc) so my budget is limited.

[LaserLover]

Hi,

I have a CO2 laser that has a 4mm output beam and for optimum focus with my 12,5mm lens the laser needs to be placed a couple of meters from the lens. I can't do that and would rather put the laser 5 - 15 cm from the cutting nozzle so I need some form of beam expander.

Does anybody have something suitable to sell for a decent price? This is a hobby project (laser cutter cnc) so my budget is limited.

What is the power output of the CO2 laser so we know If the optics on hand can handle it ?

[dar303]

Oh, sorry! It is a small one, a Synrad 48-1 16W.

[dar303]

Anybody?
............

[tocket]

Have you considered building your own? You'd need to find 2 ZnSe or Ge lenses. Ideally one positive and one negative, but it's also possible to use 2 positive.

Here is a useful source of information: http://www.newport.com/CatalogPDF/Fo...ollimating.pdf

[dar303]

Thanks, informative post as always!
I learned a new word: "keplerian beam expander"

I found another good document at Edmund optics:
http://www.edmundoptics.com/technica...rs/?&pagenum=2

I'll se what I can dig up in the form of lenses that doesn't cost as much as the laser or CNC!