CNCOLETECH CO2 Laser Lens Dia:15mm FL:2 or 50.8mm Laser Mirror CVD ZnSe Focus Focal Lens for CO2 Laser Engraving Cutting Engraver/Cutter 40W-200W

If you have a K40(Chinese) laser cutter and happen to crack your focal lens, thats a good and quick replacement. The quality is the same as the original lens that came out of the box.

I bought a 2.0 focal length CVD IIVI ZnSe lens, 19mm diameter. This lens is thicker at the edge than OEM lenses from universal laser, but it just barely fits, and cuts well enough so far. I bought another one that is listed as plano-convex like the OEM lens, but it is out of spec and too thick to use. The plano convex lens from universal laser is about 2.3mm thick, and 1.75mm thick at the edge. One caveat, which may or may not apply to all replacement lenses, is that you will need to re-calibrate your height adjustments to match the new lens. This one works best for me when I change the calibration from the original lens and set at -0.100 and re calibrate. This makes the table a bit higher, and makes the laser focus tighter than if not calibrated. I made a bunch of test cuts, going first with the calibration that worked for the OEM lens, and moving the table up in 0.050 increments. the kerf got smaller, at .050, smaller still at .100, and then started to get wider at .150 as I raised the table above the ideal focal length.

Works great with BOSS lasers.

Bought this to replace my damaged 2 OEM lens for my Thunder Laser. I did a ramp/focus test using LightBurn and found my new lens to be focused tightest at 5.5mm (vs. the nominal 6mm the machine is set up for). I run it at 5.5mm for precise work, but put it 1mm out of focus at 6.5mm when I sometimes want a wider beam for engraving. Overall, it seems to work well.

Identical to the name brand one for my laser, at a fraction of the cost.

Tutto OK, Amazon sempre una garanzia

Great value for a good quality lens. Focus was clean on install. Coating is more substantial than other inexpensive lenses that I’ve tried. We’ll see how it’s going in a few months.

I had red reviews about the dimensions being off. Mine was dead on, as checked by my digital calipers.

Great value for a good quality lens. Focus was clean on install. Coating is more substantial than other inexpensive lenses that I’ve tried. We’ll see how it’s going in a few months.

Identical to the name brand one for my laser, at a fraction of the cost.