We investigate a method of measuring the angular displacement of an aperture when the diffraction pattern rotates. The data that are on a rectangular coordinate are transformed into the data on a polar coordinate. We calculate a cross-correlation function between the diffraction pattern that is rotated and the reference pattern. When the angular displacement is within ±5°, the error is <0.050. Then, we calculated the angular displacement of the pattern on a spherical coordinate system by personal computer simulation. Consequently, when the azimuth and the elevation of its rotation axis are within ±6°, the error is <0.1°.
© 1987 Optical Society of America
Makoto Ami, Keijin Sato, Sumio Yamamoto, Osamu Kamada, and Hiroyuki Shibanuma, "Optical method of measuring angular displacement using a diffraction pattern," Appl. Opt. 26, 4310-4312 (1987)