One-shot phase-shifting phase-grating interferometry with modulation of polarization: case of four interferograms.
An experimental setup for optical phase extraction from 2-D interferograms using a one-shot phase-shifting technique able to achieve four interferograms with 90 degrees phase shifts in between is presented. The system uses a common-path interferometer consisting of two windows in the input plane and a phase grating in Fourier plane as its pupil. Each window has a birefringent wave plate attached in order to achieve nearly circular polarization of opposite rotations one respect to the other after being illuminated with a 45 degrees linear polarized beam. In the output, interference of the fields associated with replicated windows (diffraction orders) is achieved by a proper choice of the windows spacing with respect to the grating period. The phase shifts to achieve four interferograms simultaneously to perform phase-shifting interferometry can be obtained by placing linear polarizers on each diffraction orders before detection at an appropriate angle. Some experimental results are shown.
Benemérita Universidad Autónoma de Puebla, Facultad de Ciencias Físico-Matemáticas Apartado Postal 1152, Puebla PUE 72000, México. gzurita@fcfm.buap.mx
Gustavo
G
Rodriguez-Zurita
Cruz
C
Meneses-Fabian
Noel-Ivan
NI
Toto-Arellano
José F
JF
Vázquez-Castillo
Carlos
C
Robledo-Sánchez
D000465:Algorithms; D005374:Filtration / Q000295:instrumentation* / Q000379:methods*; D005583:Fourier Analysis; D007368:Interferometry / Q000295:instrumentation* / Q000379:methods*