@Phillip_Conroy …as I’ve posted…this is happening way before the lens…it’s happening coming out of the tube.
Mine is dognought shaped out of the tube on low power and before any mirrors/lenes ,still cuts fine
@Phillip_Conroy From what I remember reading a while ago, most webcam has an IR filter on it & if you remove it you can see IR. But, I tested this with an old webcam I had laying around & it worked for seeing the IR from the end of tv-remote, however it doesn’t allow me to see the laser beam (unfortunately), so I assume it is something to do with the wavelength of the laser beam being outside the range that the webcam will pick up. It would be great to have some ability to see the beam though. Would make it so much easier for alignment and the likes.
Laser power meters 100 watt are on sale for $95 http://www.bell-laser.com/#!product-page/c1iym/1cd1a226-cf6b-7b63-26a7-2d551eb6821a
Not sure, but most webcams are IR sensitive, they usually have a filter that you can remove (with a little effort). Not sure whether, it would work or not. But did work for a homemade tracking headset I made years ago using IR diodes. :\
@I_Laser Yeah I tested it already & couldn’t see the beam. However, I did a bit of reading earlier & found that you will never see the beam anyway. You will see the point that the beam reflects off objects (e.g. cutting material or dust/smoke in the air). So, it’s possible that what I had could maybe pick up the laser beam if I added dust/smoke/fog/etc to the air in the beam path.
CMOS and CCD sensors in webcams are only sensitive in the lower near IR up to around 1 micron wavelength. That is after removing the IR filter. They will not pick up the long 10.6 micron wavelength of CO2 lasers. That includes reflections from dust, smoke or anything else. Replace the webcam with a thermal imager like the systems from flir and you could view the beam reflecting off some surfaces a la video. Donut transverse mode (TEM01*) happens and it’s possible there will be nothing you can do about it since the cavity is fixed on the tube. If the vendor indicated the tube is TEM00 then you might have recourse. That being said, as long as the focused spot size is small enough for what you need, that mode likely has higher power output than the same tube operating in TEM00.