Contrast Enhancement and Reversal of a Phase Spot Array using Nonlinear Optical Phase Filtering
نویسنده
چکیده
An array of phase spots with poor intensity distribution has been contrast enhanced and reversed by nonlinear phase filtering techniques using Zinc Tetraphenyl Porphyrin as the variable phase filter in the 4-f imaging system, whose refractive index depends on the intensity of the incident beam. The intensity distributions of the unfiltered and filtered images were compared to explicitly show the contrast enhancement of the array spots and the contrast reversal of the phase spots into a phase grid. The advantage of using Zinc Tetraphenyl Porphyrin as a phase filter is also detailed.
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