IEC 61300-2-40:2000 pdf download-Fibre optic interconnecting devices and passive components – Basic test and measurement procedures – Part 2-40: Tests – Screen testing of attenuation of single- mode tuned angled optical connectors.
2 Apparatus 2.1 Optical source (S) Unless stated otherwise in the test procedure, the recommended source is a laser diode. 2.2 Excitation unit (E) Unless stated otherwise in the test procedure, the excitation unit is only a single mode fibre length greater than 2 m. 2.3 Detector (D) Unless stated otherwise in the test procedure, the recommended detector is a large sensitive area. 2.4 Temporary joints (TJ) 2.5 Screen plug for tuned connector (SP) This is an angled polished plug which has a lateral offset of the fibre core eccentrically positioned at a theoretical true position, with a tolerance from this theoretical true position. This reference plug shall be defined in the relevant connector specification. The preferred true position is located at 0,75 µm from the ferrule axis, in the direction of the adjusting axis. The fibre core is within 0,3 µm around this true position (see figure 1). In order to reduce dispersion in attenuation due to the mode field diameter difference the screen plug should use the same fibre type as the plug to be screened. 2.6 Reference adaptor (RA) The reference adaptor shall be defined in the connector detail or product specification.
3 Procedure Preconditioning procedure: The alignment and end surfaces of the plug ferrules and the adaptors shall be cleaned before test. The clean conditions shall be maintained during the test. The attenuation measurement methods shall comply with IEC 61300-3-4, Insertion method B, and shall be conducted at ambient temperature. No recovery procedures are required. The attenuation limit A ref for screening the plug under test depends on the connector construction. Measure the attenuation A o of the plug under test with a reference adaptor (RA) and a screen plug (SP). A o has to be smaller than a specific value A ref . The relation between the maximum attenuation in random mating A max that is expected for screened plugs and A ref shall be defined in the connector detail or product specification. If not, A ref has to be specified in the test procedure.