Pigtail style collimator for 1550nmwith an f=1.81mm GRIN lens in a 4mm OD housing with low return loss (inner fiber angle polished and AR coated, total device return loss will be about 50dB), with a 1 meter long, 0.9mm OD jacketed, 8/125 PM fiber, terminated with a Super FC/PC connector with the connector key aligned and locked along slow axis. The output beam diameter will be about 0.35mm at the 1/e^2 level with a full divergence angle about 6mrad. A 20mm OD removable flange, o-ring, mounting screws and a ball driver are also included. Collimator pair optimized over 50mm air gap to achieve <1.2dB loss in both directions
