title: High-resolution two-dimensional angle measurement technique based on fringe analysis.
abstract: A novel angle-measurement technique based on fringe analysis for phase-measuring profilometry is proposed. A two-dimensional (2-D) angle between two mirror surfaces is determined by least-squares fitting of a plane to the 2-D distribution of the phase difference introduced by the 2-D tilt angle. To evaluate the performance of the proposed technique, numerical simulations that use the Fourier-transform technique and the phase-shift technique for fringe analysis were performed, and the results are compared. A 2-D angle-measurement interferometer based on a Mirau interference microscope was developed that demonstrated the validity of the proposed principle. It is shown by simulation and experiment that the proposed 2-D angle-measurement technique can achieve both a wide measurement range and a high angular resolution simultaneously.
authors.affiliation: Fuji Photo Optical Company, Ltd., 1-324, Uetake, Saitama City, Saitama 330-8624, Japan. zongtao-ge@msv.fujinon.co.jp
authors.forename: Zongtao
authors.initials: Z
authors.lastname: Ge
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Takeda