Switchable, continuous, complex-amplitude modulation is demonstrated with two cascaded, twisted nematic liquid-crystal televisions (LCTV’s), both operating in phase- and amplitude-coupled modulation modes. The condition for full-range complex modulation is that one of the LCTV’s must provide a 2π-range phase modulation. A look-up table encoding method is proposed that permits the compensation of phase–amplitude coupling and nonlinearity in the two individual LCTV modulations. Experimental techniques for determining the LCTV-device parameters, for maximizing the phase-mostly modulation range and the amplitude-mostly modulation contrast, and for testing the complex-amplitude modulation are developed. Optical complex-amplitude Fresnel holograms are shown.
© 1996 Optical Society of America
Original Manuscript: April 3, 1995
Revised Manuscript: December 11, 1995
Published: August 10, 1996
Luiz Gonçalves Neto, Danny Roberge, and Yunlong Sheng, "Full-range, continuous, complex modulation by the use of two coupled-mode liquid-crystal televisions," Appl. Opt. 35, 4567-4576 (1996)