CVD ZnSe Laser Focus Lenses Diameter: 20mm FL: 2.5"/63.5mm Laser Lens Lens for CO2 Laser Engraving Cutting Engraver Cutter 40W-200W

The lens came in a nicely protected package, all wrapped up without a scratch on it. The size was the exact same as my previous one.Advice: always use gloves when fitting this to ensure the lens catches no dirt and grease, otherwise things can burn with high power.The lens was easy to fit, and the power eventually was maintained at the same level, I usually do 80% power and the lens took care of that as I have hoped.

This is a 20mm zinc-selenide lens for CO2 laser cutters.As you might expect for the money this is not particularly high-spec, but it is fine for normal users and setups.It comes in generic packaging that protects them well, so no complaints on that front.The product description has all the bases covered, so this seems to be a decent buy if it is up to specification.Overall this is impressive for the price, especially considering the ‘pro’ competition that costs far more for a very similar product.

I upgraded my CO2 laser setup with these CVD ZnSe focus lenses. I've been using them with my 100W CO2 laser for both engraving and cutting. For example, I was cutting through 6mm plywood, and the focus was sharp and precise, giving me clean, smooth edges. What's even better is that the power level felt consistent, I didn't notice any drop in performance compared to my previous, more expensive lenses.

This coated focusing lens arrives in a branded cardboard box with the lens secured into a rigid protective plastic container with a well-sized plastic insert inside it which keeps the lens secure and perfectly protected. After unpacking and inspecting it, it looks like a flawless and well made focusing lens for the asking price, it matches the claimed diameter of 20mm and the focal length also matches as near as I can tell. The box it arrives in is labelled with all the information you’d need to know at a glance and the product listing has additional bits with some useful charts and other details if needed.This should have no issues slotting right into any machine or aftermarket C02 laser head that takes a 20mm lens and I had no issues popping this into the head on my self-built machine. Nothing about the lens seems off, and I was able to calibrate and adjust the focal length on my machine’s head to match this and get a crisp line from the lens in combination with the 25mm silicone mirrors (also from PRESIONQI). The machine I've been designing and working on is very much a mishmash of 3D printed parts, flat sheet metal, extrusions and off the shelf bits where necessary.Realistically if you already happened to be using a lens of the same focal length you shouldn’t notice any significant changes unless you’re going from a badly damaged lens to this. As with the mirrors from the same company, the first impressions and results have been great, but the real test is ultimately going to be how well it lasts with the proper use and maintenance. My machine is far from done and I’m just slowly chipping away at it piece by piece, so I haven’t really had the opportunity to run the mirrors or this lens for extended periods of time outside of calibration and a few test cuts. I'll be sure to update the review if anything comes up that can be attributed to the mirrors or focusing lenses from this company, but they look as good as any other focusing lens I've used in and slightly above this price range.Just like the mirrors from this company, the lens looks to be completely identical to most other budget C02 focusing lenses you can find on Amazon from many different brands with the same coatings, focal length and size. The only actual difference is the name on the sticker applied to the box. The £25.99 price is right around the typical asking price for these white-labelled lenses on Amazon at the time of writing, so just go with whichever company happens to have a coupon or voucher at the time. Ultimately I’ve got no major faults or concerns with this and it’s a reasonable enough option if you happen to need one on short notice.

I placed this lens on my cutter and noticed crisp lines on different materials. The beam stayed steady, no weird distortions. The housing felt sturdy against minor bumps. It needs occasional wiping to stay clear, but not too often. The surface arrived free of scratches, and repeated sessions haven't revealed any flaws. The temperature remained manageable with short pauses between jobs. Alignment took minimal effort and delivered neat results. My cutting edges looked smooth without harsh burn marks. A mild reflection appeared on certain angles, though it never posed trouble. Stability and consistency have been the key benefits here. That reliability left me content with its performance thus far.

Absolutely spot-on, perfect in my G Weike 120w co2 laser.Identical to the previous lens that was in there that cost me around £50. So an absolute bargain here. Only time will tell it’s true lifespan, but it seems to be machine very well, and looks perfect. Didn’t notice any floors in the lens which is always a good sign.It’s cutting perfectly, and I will definitely be ordering another one in the future when needed.Happy to recommend

As a hobbyist laser engraver, I've tried a few different focus lenses, but this one is by far the best I've found. It's well-made, durable, and provides a clear, focused laser beam. The 20mm diameter and 2.5" focal length are perfect for my 40W CO2 laser cutter, and I've been able to achieve consistently high-quality engravings and cuts with it.One of the things I appreciate most about this lens is its ease of use. It's easy to install and adjust, and it stays in place securely. I've also found that it's very resistant to damage, even after extended use.Overall, I'm extremely satisfied with this focus lens. It's a high-quality product that has significantly improved the performance of my laser cutter.

This zinc selenide lens is made out of a special material which allows the deep infrared of the carbon dioxide laser’s light to pass through while regular glass is opaque in such deep infrared. However the surface finish of the lens may have uneven coating, care is needed to prevent damaging the delicate surface.