Accurate control of a liquid-crystal display to produce a homogenized Fourier transform for holographic memories.
We show an accurate procedure to obtain a Fourier transform (FT) with no dc term using a commercial twisted-nematic liquid-crystal display. We focus on the application to holographic storage of binary data pages, where a drastic decrease of the dc term in the FT is highly desirable. Two different codification schemes are considered: binary pi radians phase modulation and hybrid ternary modulation. Any deviation in the values of the amplitude and phase shift generates the appearance of a strong dc term. Experimental results confirm that the calculated configurations provide a FT with no dc term, thus showing the effectiveness of the proposal.
Márquez
Andrés
A
Departamento de Física, Ingenierýa de Sistemas y Teoría de la Señal, Universidad de Alicante, Apartado 99, 03080, Alicante, Spain. Andres.Marquez@ua.es
Gallego
Sergi
S
Méndez
David
D
Alvarez
Mariela L
ML
Fernández
Elena
E
Ortuño
Manuel
M
Neipp
Cristian
C
Beléndez
Augusto
A
Pascual
Inmaculada
I