Patent ID: 9645044
Date: 2017-05-09
CPC Classifications: G01M,G02B

Claim:
1. A controlled-contact method of measuring an insertion loss of a device-under-test (DUT) connector having a first ferrule with a first optical fiber and a first end face with a reference connector having a second ferrule with a second optical fiber and a second end face, comprising: axially aligning the first and second ferrules so that the first and second end faces are confronting and spaced apart to define a variable gap having a gap distance with an initial value; reducing the gap distance at a first rate by moving the reference and DUT connectors together at a connector velocity in the range of 1 mm/s to 5 mm/s while measuring a coupled optical power between the first and second optical fibers; reducing the gap distance at a second rate slower than the first rate by reducing the connector velocity to be in the range from 5 μm/s to 500 μm/s while measuring the coupled optical power, until the first and second end faces come into contact at a gap distance of 0 μm, while continuing to measure the coupled optical power; after the first and second ferrules are in contact, either maintaining or increasing the connector velocity and subjecting the ferrules to an axial compression force while continuing to measure the coupled optical power; and measuring the insertion loss based on the measured coupled optical power as a function of the gap distance.