Method of contactless detection of moving object absolute position by making use of coherence granularity phenomenon and apparatus for making the same

摘要

A method of contactless detection of the absolute position of a rotating or shifting object using a coherent graininess phenomenon, wherein the object (11) is illuminated by a coherent or quasi-coherent beam from a radiation source (22) operating in the near, near infrared or near ultraviolet region of the spectrum. The essence of the solution is that, first, in the calibration phase, the coherent grain field generated by the examined rotating or shifting object (11) for each position of its rotation or displacement is recorded on the image sensor (5) along with the amount of rotation or displacement when this information is stored in the memory of the sensor (5) or the control and evaluation system (4) recording the change in the coherent grain field. Consequently, at the stage of measuring and evaluating the rotation positioning or displacement position detection, the recorded coherence granularity field for the unknown position of the object to be examined (11) is compared to the coherence grain field images stored during calibration, and calibration and measurement output images are identified with highly correlated field field records. granularity, which always corresponds to one particular position of rotation or displacement of the object under investigation.