title: Optical method of measuring angular displacement using a diffraction pattern.
abstract: 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 degrees , 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 degrees , the error is <0.1 degrees .
authors.forename: M
authors.initials: M
authors.lastname: Ami
authors.forename: K
authors.initials: K
authors.lastname: Sato
authors.forename: S
authors.initials: S
authors.lastname: Yamamoto
authors.forename: O
authors.initials: O
authors.lastname: Kamada
authors.forename: H
authors.initials: H
authors.lastname: Shibanuma