title: Canceling the momentum in a phase-shifting algorithm to eliminate spatially uniform errors.
abstract: In phase-shifting interferometry, phase modulation nonlinearity causes both spatially uniform and nonuniform errors in the measured phase. Conventional linear-detuning error-compensating algorithms only eliminate the spatially variable error component. The uniform error is proportional to the inertial momentum of the data-sampling weight of a phase-shifting algorithm. This paper proposes a design approach to cancel the momentum by using characteristic polynomials in the Z-transform space and shows that an arbitrary M-frame algorithm can be modified to a new (M+2)-frame algorithm that acquires new symmetry to eliminate the uniform error.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Hibino
authors.forename: Yangjin
authors.initials: Y
authors.lastname: Kim