Lensed Adapter Core, 1550 nm AR Coated, FP4 Series Adapters

The all new FP4-COL-1550 Fiber Adapter Core collimates the laser beam from a fiber tip so that the beam does not overfill the active area of the 818 and 918D series IR and IG detectors.  It employs a 1.8 mm diameter graded index lens with an AR coating between 1250 to 1650 nm.  This part is inserted into the FP4 series fiber adapters such as FP4-FC, FP4-ST, FP4-SC, and FP4-LC.  The rubber gasket around the part quickly ensures a secure placement of the collimator inside the fiber adapter without using screws, however, threaded holes are available for bolting it to the adapter for consistent measurements.  The coating is optimized for the telecommunication wavelengths at around 1310 and 1550 nm.  Typical insertion loss is better than 0.2 dB.  Two 2-56 screws are included to provide handling convenience, and two 0-80 screws are included to allow tightening FP4-COL-1550 onto the fiber adapters.  Note that the power reading is no longer calibrated, due to the loss through the lens.  It replaces the obsolete FP4-CORE-IR.