SPECKLE IMAGE CORRELATED POSITION TRANSDUCER

摘要

PROBLEM TO BE SOLVED: To provide a speckle image correlated position transducer allowing the high-resolution measurement of a position or displacement. SOLUTION: A speckle reading head includes a light source outputting the light to an optically rough face. The light scattered from this face includes speckles, and the scattered light is imaged on an image detector and captured and stored. A second image is captured and stored. Two images are compared with each other in the cyclic displacement direction at different offsets. The displacement quantity between the reading head and the face generated while two images are captured is shown by the comparison having the highest value.