During installation and maintaining industrial large-scale structures there is a necessary of usage angular measuring devices such as autocollimation systems, which allows controlling some characteristics of objects. Moreover, autocollimation systems are often used in science experiments and technical modeling. Parallelism, coaxiality, other alignments, yaw, roll, pitch or deformation angles are the wide spread parameters often required to be determined. However, autocollimation systems have some principal issues. Errors caused by incoming radiation vignetting is one of them. Despite the resulting image at the detector’s sensitive area is reduced by entrance aperture, the errors of such vignetting could be eliminated being systematical ones. Implementation of the software model, which traces rays through the simulated autocollimation system, predicts the illuminance distribution and calculates vignetting errors are the purposes of this survey. The amount of precalculated vignetting errors for each reflecting element position which is fixed at the object to control is saved at any database. Due to the simple recovery algorithm this amount gives the possibility to reconstruct the real object position and eliminate vignetting error. Furthermore, the ability to model different types of apertures, reflecting elements and emitter’s radiation patterns incorporated into the software gives the ability to apply one at much more complicated systems and decrease the time and exps of a design process.