by r691175002 » Fri Nov 04, 2011 4:36 pm
I'm on marcona's side here, mostly because from a safety perspective diodes in the near IR scare me.
You cannot see the light but unlike a CO2 laser the beam is not stopped by the outer layers of your eye. That means that any light you see (Even if you glimpse at the spot where cutting is occurring) will be focused by your eye into a tiny spot on your retina. This is compounded by the fact that you will be unaware damage is occurring so the protective reflexes will not kick in.
When a glimpse at the dot of the laser has the potential to permanently damage your eyes during things like initial set-up. At 35W even reflections of the beam are trouble. And of course, it becomes much harder to ensure safety when you cannot use regular glass or acrylic for protection.
Sure a CO2 laser is also dangerous, but at 40W you really need to stick your face in the beam. You don't get surprise invisible reflection blindness.