Home – Home – Jornals – Avtometriya 2005 number 4

Two basic schemes of laser triangulation sensors used for sensing a mirror surface are analyzed: the first one uses sensors with the photo-registration plane tilted to the optic axis according to the Scheimpflug principle, and the other uses sensors with the plane that is orthogonal to the optic axis. The measurement errors are estimated. Comparative analysis of metrological characteristics of the schemes is presented. The conditions of Scheimpflug principle applicability are determined. It is shown that for a certain ratio of parameters of the optical system to probing light beam, the scheme with an orthogonal registration plane can ensure a smaller level of measurement errors than the scheme with a tilted output plane, despite the presence of defocusing. This advantage remains valid only at small surface tilts. Peculiarities of sensing a nonstationary surface by the triangulation systems are considered.