Schott RG850

3mm thickness meant it fit perfectly into my custom mount without any extra shimming. The cut edges were clean and the transmission curve matches the datasheet right where I needed it for my NIR imaging rig. Exactly what I needed for longpass work at 850nm.

Cut the 3mm thick filter to size for my spectroscopy rig, and the edge quality is surprisingly clean. Blocks everything below 850nm exactly as specified, no bleed-through.

Snapped this into my laser setup expecting to cut the visible glare, and it does exactly that — everything past 850nm comes through clean while the shorter wavelengths just vanish. The 3mm substrate feels substantial and the edges are nicely polished, no chips or haze anywhere.