The creation of a field-controlled variation of the index of refraction in a liquid crystal cell has been analyzed and experimentally verified. To obtain a spherical lens utilizing a simple electrode structure and capable of focusing arbitrary incoming polarizations requires four flat nematic liquid crystal cells. With electrodes fabricated well within the current capability of photolithography, near diffraction-limited performance in terms of the optical transfer function is predicted. The focusing capability of a liquid crystal lens was demonstrated using a single cell with linear transparent electrodes. A plano-convex cylindrical lens for a single incoming polarization was thus created. While the cell had a crude electrode structure, it affirmed all the major qualitative predictions. The fringing along the edge of the electrodes required for eventually obtaining near diffraction-limited performance was observed.
© 1984 Optical Society of America
Original Manuscript: February 7, 1983
Published: January 15, 1984
Stephen T. Kowel, Dennis S. Cleverly, and Philipp G. Kornreich, "Focusing by electrical modulation of refraction in a liquid crystal cell," Appl. Opt. 23, 278-289 (1984)