Multimode plastic optical fibre, step-index, core diameter 750 mm, numerical aperture 0.50, available in 1 m / 2 m / 3 m lengths (singleended bare fibre). Optical Parameters · Core material: Polymethyl methacrylate (PMMA) Cable Core diameter: 750mm (nominal). Core diameter tolerance: ± 25mm (or specify ±3%). · Numerical aperture (NA): 0.50 (nominal). · Two Meter Long Three Meter Long