The Influence of Eccentricity and Pyramidal Error on Rotation Angle Measurement Within a 360-Degree Range

In this study, the dual-autocollimator method was used to investigate the accuracy of the metrological calibration of multi-face polygons, focusing on the effects of pyramidal error and eccentricity. Measurements were conducted on a 12-face polygon, where mirrors positioned 90° apart were observed using two autocollimators — one as a reference and the other for measuring the yaw angle deviations as the polygon was rotated by 30°. A reading of the results for 12 angles with four repetitions was performed. Different levels of variability in the readings were observed for the mirrors. This article presents the procedure for assessing the sources and values of uncertainty in the measurement. The errors of misalignment and eccentricity of the rotary table axis and the angle standard were considered. Significant impacts of pyramidal error and eccentricity were identified.