Triangulation model taking into account light sheet curvature

Abstract

This paper examines the problem of systematic measurement errors in optical triangulation when some light sheets that illuminate the measured surface exhibit non-negligible bending (curvature). The problem is demonstrated experimentally by triangulation measurement of two reference bodies whose geometry reveals systematic measurement errors due to light sheet curvature. To correct these errors a triangulation model is developed which assumes parabolic light sheet shape and allows exact solution of system equations. Test measurements show that the model successfully compensates for systematic measurement errors originating from the curvature of light sheets.