This master thesis investigates the conceptual development of an opto-electronic perpendicular utilizing electro-active glass. An exactly aligned laser beam serves as reference axis to enable the measurement of relative movements, caused by geological activities, within underground structures. This application is designed as a monitoring system, which automatically triggers maintenance tasks. The paper's scope covers the documentation as well as the implementation of several image processing techniques for camera aided position determination. The primary process is composed of a logical sequence of four sub-procedures: at first, during image preprocessing, the contrast is normalized and the noise is suppressed through digital filtering; the segmentation of image objects is accomplished by binary morphology, employed ideas to calculate a suitable threshold are Otsu's method, brightness class average, Gaussian curve intersection and maximal normal distance; the determination of an object's center is performed through the computation of its center of gravity, its Gaussian curve extremum or fitting of a conic, to be specific the approximation of a circle and an ellipse; the last step is coordinate mapping through linear homography, polynomial control points or the newly introduced tensor interpolation via basis function sectioning and quad tree decomposition. The different approaches are evaluated through experiments with a laboratory prototype. Consequently, verification and analysis is carried out on the numerical results to give a statement about the suitability of the different methods for such a kind of measurement instrument.