Method of determining the tilt angle of coded surveyor's staffs

摘要

The angle detection method involves using an electronic levelling device with an optical imaging system (5), a position-sensitive optoelectronic detector (8) and a processor (9). The code pattern obtained from the levelling beam via the optical imaging system is compared with a reference code pattern, the obtained difference used for evaluating the distortion function of the code elements, in turn used to determine the tip angle. Pref. the distance (So) between the optical imaging system and the levelling beam is corrected via a trigonometric method, in dependence on the determined tip angle.