title: Two-step spatial phase-shifting radial shearing interferometery with circular gratings.
abstract: This Letter presents a simple radial shearing interferometery with circular gratings to measure the radial first-order derivative of arbitrary wavefront phase. Two spatial phase-shifted radial shearing interferograms can be simultaneously obtained by the system, and a two-step phase-shifting algorithm with arbitrary phase-shift value is proposed for phase retrieval. The measurement for spherical wave has shown the feasibility and validity, and the optical system is used to measure the radial first-order derivative of projection wavefront phase of a propane flame with plane incident wave.
authors.affiliation: Department of Information Physics and Engineering, Nanjing University of Science and Technology, Nanjing, China.
authors.forename: Jia
authors.initials: J
authors.lastname: Wang
authors.forename: Yang
authors.initials: Y
authors.lastname: Song
authors.forename: Zhen-hua
authors.initials: ZH
authors.lastname: Li
authors.forename: An-zhi
authors.initials: AZ
authors.lastname: He