Extrusion of chalcogenide glass preforms and drawing to multimode optical fibers

We report on viscosity of a Ge17As18Se65 glass over the temperature range of 280–420 °C and the successful co-extrusion and fiber-drawing of two chalcogenide glass boules to form a core/clad. pair. The co-extrusion produces a preform with optimum diameter stability and core/clad. glass ratio, and minimum defects at the core/clad. interface in the middle 120–200 mm region of a 270 mm long preform. Core/clad. fiber is drawn successfully from the extruded preform. An optical loss of 1.7 dB m−1 at 1666 cm−1 (6.0 μm) and 6.7 dB m−1 at 6649 cm−1 (1.55 μm) is reported.