A data sheet titled “SingleMode Mid InfraRed Fiber” is available from IRphotonics. Downloadable from the company Web site, it notes that the fibers are manufactured with a fluoride process that enables a wide range of cutoff wavelengths, and that they are suitable for applications requiring a precise core diameter and low attenuation. The document lists features such as transparency in the UV, VIS, NIR and mid-IR, and fiber specifications including a spectral transmission range of 300 to 4500 nm, a numerical aperture of 0.10 to 0.25 and an operating temperature of –20 to 150 °C (higher with special coating). Dopant, optical, and mechanical and geometrical specifications are included.