Interferometric determination esp. of rotational movements of object being measured

摘要

The interferometric determination involves a pair of measuring beams (3,4) emanating from a laser (7) which are reflected back from an object (1) being measured as signal beams (5,6). Each measuring beam (3,4) runs through a separate heterodyne-interferometer (12,13), in which a component is branched off as a reference beam (16,17). The signal beams (5,6) reflected back from the object (1) being measured in the interferometer are respectively superimposed on the reference beams, and the speed information of the measurement object (1) is obtained from the resulting output signals of both interferometers at detectors (23,24). In addition, the complementary interferometer outputs at detectors (25,26) are differentially combined to optimise the signal sent to an electronic evaluation unit.