INTECIN   20395
INSTITUTO DE TECNOLOGIAS Y CIENCIAS DE LA INGENIERIA "HILARIO FERNANDEZ LONG"
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Simple birefringent polarization modulator: application to PSI
Autor/es:
FRANCISCO E. VEIRAS; LILIANA I. PEREZ; MARÍA TERESA GAREA
Lugar:
Porto
Reunión:
Congreso; 8th Ibero American Optics Meeting/11th Latin American Meeting on Optics, Lasers, and Applications.; 2013
Institución organizadora:
Red Iberoamericana de Optica
Resumen:
Phase information recovered in phase shifting interferometry relies on the introduction of phase shifts between the branches of an interferometer. This is typically achieved by means of mirrors driven by piezoelectric transducers, which modify the optical path of one of the branches of an interferometer. Depending on the algorithm for phase recovery used, the precise control of the phase shift introduced becomes more or less critical. Generally, if the number of phase steps (and consequently the recorded interferograms) is increased, it is possible to reduce the precision of the phase intervals and therefore use more economical phase shifters. This work deals with the possibility of using an anisotropic crystal slab as a phase shifter. Unlike other experimental schemes where wave plates are rotated azimuthally, we analyze the use of different crystal cleavages and ways of rotation. The phase shifter proposed here is inexpensive and can be easily calibrated, so it is possible to use it with algorithms that require either a low or high quantity of interferograms. The experimental design can generally be applied to interferometers where the input signal splits into two linear orthogonal polarizations. This way, the phase shifter acts as a polarization modulator. As an example, we analyze a simple conoscopic interference setup where the element under study corresponds to a birefringent crystal slab.