Use the LP500 longpass filter when your system needs a sharp 500 nm edge with strong blue blocking. OPTOStokes specifies 510–1100 nm transmission at >90%, 350–490 nm blocking at <1%, 1.1 mm substrate thickness, and 60/40 scratch-dig. The product page positions it for blue-block fluorescence, microscopy, laser/LED systems, flow cytometry, and compact OEM builds. That combination makes it practical when you want clean separation above 500 nm without sacrificing downstream yellow, red, or NIR throughput. OPTOStokes also lists cutoff tuning from 495–510 nm, custom sizing, and OEM series supply, so you can validate with a standard part and then tighten the spec around your exact optical path.