Polarization-controlled contrasted images using dye-doped nematic liquid crystals.
We explore the polarization dependence of the nonlinear response of a planar nematic liquid crystal cell doped with 1% wt of methyl red dye. The results obtained show that the refractive index change can be switched from a positive value to a negative one as the polarization of the beam changes from parallel to perpendicular with respect to the rubbing direction. This property is exploited in a phase contrast system, where a dynamic phase filter is photoinduced in a liquid crystal cell placed in the system's Fourier plane. Real-time contrast inversion in the resulting images is demonstrated.
Porras Aguilar
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Departmento de Optica, Instituto Nacional de Astrofisica, Optica y Electronica, Apartado Postal 51 y 216 72000Puebla, Pue. Mexico.
Ramirez-San-Juan
J C
JC
Baldovino-Pantaleon
O
O
May-Arrioja
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D
Arroyo Carrasco
M L
ML
Iturbe-Castillo
M D
MD
Sánchez-de-la-Llave
D
D
Ramos-Garcia
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R