Homebrew PCBs

Steve Wiseman wrote:
> 2009/1/19 Mark Robinson <mark.robinson@...>:
>> Juan EA7FNJ wrote:
>>> Hi guys!
>>> I''ve seen this: http://c4r0.skrzynka.org/_hv/index.php?page=lasers/cnc2
>>>
>>> I was thinking: why don't use this kind of laser to burn the
>>> photoresist board. After you develop it and ready for the etch. I
>>> knoww the CO2 laser but it's more expensive than a simple burn laser
>>> from a DVD burner.
>> A laser from a DVD burner should be quite adequate to expose photoresist.
> 
> I think Juan's contemplating burning the resist off, rather than exposing it.
> I've got a 25W CO2 laser marker, (google synrad fenix) but no etching
> gear here. If anyone wants to send me a bit of photoresist board, I'll
> blast a few test images onto it at varying powers and send it back to
> you for etching. Working area is credit card size, spot size is 180uM.
> It'll almost certainly burn away the etch resist - but I don't know if
> it will do odd thermal stuff to the remaining areas, and what the
> effective resolution will be. It'll definitely not burn the copper,
> with a puny 25W.
> 
> ('Here' is Cambridge, England)

Hi,
What precautions are needed for eye protection against stray reflections?