An improved automatic measurement setup for inner diameter of outer conductor in coaxial air lines

An improved automatic measurement setup for measuring inner diameter of outer conductor (IDOC) in coaxial air lines with precision connectors, including N, 7 mm, 3.5 mm, 2.92 mm, 2.4 mm, and 1.85mm, is introduced. The improved setup can accurately measure the straightness and the position of measured cross-section of IDOC. Multi-gauge calibration method and orthogonal regression algorithm are used to achieve measurement uncertainty smaller than 0.3µm. As an example, the measurement results of air lines with precision 2.92 mm and type N connectors are shown.